Yes, studying history will help us understand how simple to complex living entities evolved on earth, citing examples further- For evolution of viruses there are three main hypotheses 1- progressive hypothesis states that viruses arose from genetic material, 2- regressive hypothesis states that viruses are remnants of cellular organisms and 3- the virus first hypothesis states that they coevolved with other cellular hosts.Viruses and bacteria share a common ancestor – a fully functioning, self-replicating cell that lived billions of years ago. From this cell, bacteria have evolved in the direction of increasing complexity( simple to complex), while viruses have gradually shed genes(complex to simple) they found they didn’t need – until they could no longer even reproduce on their own. But like humans –bacteria evolved to become more complex, viruses became simpler. Today, viruses are so small and simple, they can’t even replicate on their own. Another example is size of the brain, the size is directly related to the complexity, in nearly seven million years the human brain has tripled in size. Early skulls give us evidence about the volumes of ancient brains and some details about the relative sizes of major cerebral areas. Australopithecus afarensis, had skulls with internal volumes of between 400 and 550 milliliters, whereas chimpanzee skulls hold around 400 ml and gorillas between 500 and 700 ml.The first fossil skulls of Homo erectus had brains averaging a bit larger than 600 ml. Early Homo sapiens had brains within the range of people today, averaging 1,200 ml or more. This is how our brains complexity increased and now has started decreasing due to our life style and various other environmental factors.
yes, studying history can help us to get idea of evolution as life on earth was began 3.5 to 4 billion years ago and it has been evolving ever since. At first it is believed that all organisms were simple and single celled. much later multicellular organisms were evolved so if we start looking from history we can get an idea of evolution of simple to complex living entity.
Conventional wisdom holds that complex structures evolve from simpler ones, step-by-step, through a gradual evolutionary process. As complexity arises, it may help an organism survive better or have more offspring. If so, it will be favored by natural selection and spread through the population. Mammals, for example, smell by binding odor molecules to receptors on nerve endings in their nose. AS we learn more about history, we would get a deep understanding about "how did the complex life evolve" or "theory of evolution". Thus, studying history helps us to understand evolution of simple to complex life entity.
Yes, studying history helps us getting the idea of evolution of simple to complex living entity. according to scientists first of all simple organisms exist on earth. there are many hypothesis for development of this simple organisms on earth some group of scientists believe that life came from outer space as spores while another group explained that life came from a non-cellular component such as decaying matters like mud. other some group of scientists believe life originated from non-living organic molecules like proteins and RNA and after that this simple organisms developed by endosymbiosis and become more complex living entity.
Yes, studying history will help us understand how simple to complex living entities evolved on earth The 17th century discovery of living forms existing invisible to the naked eye was a significant milestone in the history of science, for from the 13th century onward it had been postulated that “invisible” entities were responsible for decay and disease. The word microbe was coined in the last quarter of the 19th century to describe these organisms, all of which were thought to be related. As microbiology eventually developed into a specialized science, it was found that microbes are a very large group of extremely diverse organisms. Microbiology essentially began with the development of the microscope. Although others may have seen microbes before him, it was Antonie van Leeuwenhoek, a Dutch draper whose hobby was lens grinding and making microscopes, who was the first to provide proper documentation of his observations. Although his observations stimulated much interest, no one made a serious attempt either to repeat or to extend them. Leeuwenhoek’s “animalcules,” as he called them, thus remained mere oddities of nature to the scientists of his day, and enthusiasm for the study of microbes grew slowly. The early Greeks believed that living things could originate from nonliving matter (abiogenesis) and that the goddess Gea could create life from stones. Aristotle discarded this notion, but he still held that animals could arise spontaneously from dissimilar organisms or from soil. This advance in understanding was hard fought, involving series of events, with forces of personality and individual will often obscuring the facts.Darwinian evolution can be depicted as a tree, with the original organism at the base of the trunk and the myriad evolutionary changes that occur over time generating the branches and even smaller twigs at their tips. In contrast, evidence that has been accumulating since the 1970s has firmly established that microbial evolution occurs differently. The tree analogy is inaccurate when describing microbial evolution. This wider, interspecies transfer is called horizontal transfer. It is one route by which a bacterium can become resistant to one or more antibiotics. A bacterium that carries the genetic determinants for resistance to an antibiotic may be able to transfer the gene to another, unrelated bacterium, which then also becomes resistant to the antibiotic.
The acceptance of biological evolution, the preceding term pronounced is an essential part of the modern scientific explanation of the natural world. Most scientists and major religions in the Western World have long since incorporated it into their understanding of nature and humanity. However, some churches still maintain that there was a special and independent creation of every species and that life forms do not change through time from generation to generation. These "creationists" often share beliefs about the Judeo-Christian Bible that were widely held, even by scientists, during the early 19th century and before.Lamarck believed that microscopic organisms appear spontaneously from inanimate materials and then transmute, or evolve, gradually and progressively into more complex forms through a constant striving for perfection. The ultimate product of this goal-oriented evolution was thought by Lamarck to be humans. He believed that evolution was mostly due to the inheritance of acquired characteristics as creatures adapted to their environments. That is, he believed that evolution occurs when an organism uses a body part in such a way that it is altered during its lifetime and this change is then inherited by its offspring. For example, Lamarck thought that giraffes evolved their long necks by each generation stretching further to get leaves in trees and that this change in body shape was then inherited. Likewise, he believed that wading birds, such as herons and egrets, evolved their long legs by stretching them to remain dry. Lamarck also believed that creatures could develop new organs or change the structure and function of old ones as a result of their use or disuse.
Yes! Studying history can help us understand the idea of evolution as life on earth. Evolution is one of the greatest theories in all of science. It sets out to explain life: specifically, how the first simple life gave rise to all the huge diversity . The evolution of biological complexity is one important outcome of the process of evolution. Once simple life emerged, it gradually evolved into more complex forms, eventually giving rise to animals and plants. After simple cells first appeared, there was an extraordinarily long break – nearly half the lifetime of the planet – before complex ones evolved. In fact, it appears that simple cells gave rise to complex ones just once in 4 billion years of evolution. Thus according the theories studied , we can say that history helps us get the idea of evolution of simple to complex living entity.
Yes, studying history will help us understand how simple to complex living entities evolved on earth The 17th century discovery of living forms existing invisible to the naked eye was a significant milestone in the history of science, for from the 13th century onward it had been postulated that “invisible” entities were responsible for decay and disease. The word microbe was coined in the last quarter of the 19th century to describe these organisms, all of which were thought to be related. As microbiology eventually developed into a specialized science, it was found that microbes are a very large group of extremely diverse organisms. Microbiology essentially began with the development of the microscope. Although others may have seen microbes before him, it was Antonie van Leeuwenhoek, a Dutch draper whose hobby was lens grinding and making microscopes, who was the first to provide proper documentation of his observations. Although his observations stimulated much interest, no one made a serious attempt either to repeat or to extend them. Leeuwenhoek’s “animalcules,” as he called them, thus remained mere oddities of nature to the scientists of his day, and enthusiasm for the study of microbes grew slowly. The early Greeks believed that living things could originate from nonliving matter (abiogenesis) and that the goddess Gea could create life from stones. Aristotle discarded this notion, but he still held that animals could arise spontaneously from dissimilar organisms or from soil. This advance in understanding was hard fought, involving series of events, with forces of personality and individual will often obscuring the facts.Darwinian evolution can be depicted as a tree, with the original organism at the base of the trunk and the myriad evolutionary changes that occur over time generating the branches and even smaller twigs at their tips. In contrast, evidence that has been accumulating since the 1970s has firmly established that microbial evolution occurs differently. The tree analogy is inaccurate when describing microbial evolution. This wider, interspecies transfer is called horizontal transfer. It is one route by which a bacterium can become resistant to one or more antibiotics. A bacterium that carries the genetic determinants for resistance to an antibiotic may be able to transfer the gene to another, unrelated bacterium, which then also becomes resistant to the antibiotic.
After inoculation, lid of the Petri dish is sealed with adhesive tape to prevent microorganisms from the air contaminating the culture – or microbes from the culture escaping. But we do not seal all the way around the edge – as oxygen needs to get into the dish to prevent the growth of unnecessary anaerobic bacteria
When spreading the bacterial culture onto the dish,the lid should be minimal amount to prevent any unwanted microbes from contaminating the culture. Finally ,before the plate is incubated so that the bacteria can grow,the lid is sealed using sticky tape.
yes this is the one of the method where sticky tape is used. but when we are performing in lab we usually do not seal the plate. then how the contamination is not occuring?
In growth curve experiment all nutrients are available and conditions are favourable, but some organisms select to go stationary phase instead of log phase Why?
The organisms usually goes to stationary phase when the saturation level is achieved. In stationary phase usually the rate of bacterial growth is equal to the rate of bacterial cell death. the arise of stationary phase may come due to depletion of some amount of nutrient or there may be an accumulation of the inhibitory product like the organic acids.
Bacteria don’t have a fixed lifespan because they don’t grow old. When bacteria reproduce, they split into two equal halves, and neither can be regarded as the parent or the child. You could say that so long as a single one of its descendants survives, the original bacterium does too.Bacteria divide somewhere between once every 12 minutes and once every 24 hours So the average lifespan of a bacterium is around 12 hours or so. While the division time or the time between the end of replication and completion of division (D period), is the time that elapses between completion of a round of DNA replication and completion of cell division. This is about 20 min. Hence the time for the replication cycle the period required for replication or C period plus D period is essentially constant in bacterial cultures with doubling times shorter than 60 min.
Bacteria life span varies by type; some has very short life span (minutes to hours) and some has up to years (in inanimate surface lives may be up to hundreds years).Bacteria divide somewhere between once every 12 minutes and once every 24 hours. So the average lifespan of a bacterium is around 12 hours or so.The single chromosome of a bacterium is a loop of double-stranded DNA. The number of bases can vary from one species to another. The well-known bacteria E. coli has 4.7 million base pairs that take about 40 minutes to replicate, implying a speed of over 1,000 bases per second.
Bacteria don't have a fixed lifespan because they don't grow old . When bacteria reproduce , they split into two equal halves , and neither can be regarded as the parent or the child . You could say that so long as a single one of its descendants survives , the original bacterium does too . Individual bacteria can also turn themselves into spores with a tough coat to protect themselves from dry conditions . Bacterial spores have been successfully revived from 250 - million - year - old salt crystals found in New Mexico in 2000. But if we assume that the global bacteria population is stable, then it follows that one bacterium must die for each new one that is produced. Bacteria divide somewhere between once every 12 minutes and once every 24 hours. So the average lifespan of a bacterium is around 12 hours or so.
Synchronous Culture / Synchronous growth of a bacterial population is that during which all bacterial cells of the population are physiologically identical and in the same stage of cell division cycle at a given time. Synchronous growth helps studying particular stages or the cell division cycle and their interrelations. In most of the bacterial cultures the stages of growth and cell division cycle are completely random and thus it becomes difficult to understand the properties during the course of division cycle using such cultures. To overcome this problem, the microbiologists have developed synchronous culture techniques to find synchronous growth of bacterial population.
Synchronous growth is the growth of bacteria such that all the bacteria are at the same stage in their growth cycle (e.g exponential phase,stationary phase).Because the same cellular reactions occur simultaneously throughout the bacterial population, synchronous growth permits the detection of events not normally detectable in a single cell or in a population consisting of bacteria in various stages of growth. In a normal batch culture of fluid, or on an agar plate, bacteria in the population exhibit a range of sizes, ages, and growth rates. In contrast, the bacteria in a synchronized culture are virtually identical in terms of these parameters and synchronized growth is imposed in laboratory. The population of bacteria can be filtered to obtain bacteria of a certain size range. Usually, the filter that is used has very small holes. All but the smallest bacteria in a population are excluded from passing through the filter. Because the smallest bacteria are frequently the youngest bacteria, the filtering method selects for a population comprised of bacteria that usually have just completed a division event. When the bacteria are suspended in fresh growth medium the population will subsequently grow and then divide at the same rate.Bacteria of the same size can also be recovered using special techniques of centrifugation, where the bacteria in the fluid that is spinning around in a centrifuge are separated on the basis of their different densities. The smallest bacteria will have the lowest density and so will move furthest down the centrifuge tube.Their another method of obtaining a synchronous bacterial population involves the manipulation of some environmental factor that the bacteria depend on growth.
Cell synchronization is a process by which cells in a culture at different stages of the cell cycle are brought to the same phase. Cell synchrony is a vital process in the study of cells progressing through the cell cycle as it allows population-wide data to be collected rather than relying solely on single-cell experiments.Synchronous growth is the growth of bacteria such that all the bacteria are at the same stage in their growth cycle (e.g., exponential phase, stationary phase). Because the same cellular reactions occur simultaneously throughout the bacterial population, synchronous growth permits the detection of events not normally detectable in a single cell or in a population consisting of bacteria in various stages of growth.The types of synchronization are broadly categorized into two groups; physical fractionization and chemical blockade.
In a clear manner Synchronous means where the growth of the bacteria is at the same stage; for example all the bacteria will be in the exponential phase. synchronous growth is usually imposed in laboratory. a synchronous condition is maintained by either manipulating environmental conditions like changing the temperature in intervals or by adding the more nutrients.
Synochronous growth is the growth in which all the organismas are in the same stage in their growth cycle. All cells in the culture will divide at the same time,grow for a generation time. Synochronous growth provides the entire cell crop in the same stage of the growth.
Synchronous culture can define as the growth process of the microbial population, where the individual cells show synchrony with the other cells in the culture medium by growing at the same growth phase for the given generation time.The main characteristic of synchronous growth is that all the microbial cells are physiologically identical by growing at the same division cycle at the same time. Therefore, we can say that the entire microbial population remains uniform concerning cell growth and division.
In shift-up, a culture is transferred from a nutritionally poor medium to a richer one; and shift-down, where a culture is transferred from a rich medium to a poor one. In a shift-up experiment, there is a lag while the cells first construct new ribosomes to enhance their capacity for protein synthesis. In a shift-down experiment, there is a lag in growth because cells need time to make the enzymes required for the biosynthesis of unavailable nutrients.
In shift-up, a culture is transferred from a nutritionally poor medium to a richer one and shift-down, where a culture is transferred from a rich medium to a poor one.
In Shift down process, a nutritional culture is transfered from high medium to low medium. In Shift up process, a nutritional culture is transformed from low medium to high medium content.
Quorum sensing is a process of cell-cell communication that allows bacteria to share information about cell density and adjust gene expression accordingly.
Quorum sensing (QS) is a process of cell–cell communication that allows bacteria to share information about cell density and adjust gene expression accordingly. This process enables bacteria to express energetically expensive processes as a collective only when the impact of those processes on the environment or on a host will be maximized. Among the many traits controlled by quorum sensing is the expression of virulence factors by pathogenic bacteria. It can also be defined as ,"a bacterial cell–cell communication process that involves the production, detection, and response to extracellular signaling molecules called autoinducers (AIs)". Gram-positive and Gram-negative bacteria use different types of QS systems.
It means the number of members of a group required to be present to carry out an activity legally. In this process bacteria communicate via secreted signaling molecular called “autoinducers” which contribute to the regulation of the expression of particular genes. It occurs within a single bacterial species as well as between diverse species. In some local insects use quorum sensing to determine where to nest. Quorum sensing has two type of bacteria. Gram positive bacteria and Gram negative bacteria. Gram positive bacteria. Eg:- Bacillus subtulis and Streptococcus pneumonia use QS to develop competence. Gram negative bacteria. Eg:- QS in Vibrio fischeri- Bioluminescence is define as the emission of visible light from living organism.
Quorum sensing is a process of cell–cell communication that allows bacteria to share information about cell density and adjust gene expression accordingly. Bacterial communication relies on versatile chemical signaling molecules called autoinducers, which regulate bacterial gene expression in a process known as quorum sensing. Like languages between humans, these signals vary between species. Some bacterial species can interpret many different signals, while others respond to a select few. Quorum sensing allows individual bacteria within colonies to coordinate and carry out colony-wide functions such as: sporulation, bioluminescence, virulence, conjugation, competence and biofilm formation.
Quorum sensing is a system of stimulus and response correlated to population density. Many species of bacteria use quorum sensing to coordinate gene expression according to the density of their local population. In similar fashion, some social insects use quorum sensing to determine where to nest. In addition to its function in biological systems, quorum sensing has several useful applications for computing and robotics.
Quorum sensing can function as a decision-making process in any decentralized system, as long as individual components have: (a) a means of assessing the number of other components they interact with and (b) a standard response once a threshold number of components is detected. Some of the best-known examples of quorum sensing come from studies of bacteria. Bacteria use quorum sensing to coordinate certain behaviors based on the local density of the bacterial population. Quorum sensing allows individual bacteria within colonies to coordinate and carry out colony-wide functions such as: sporulation, bioluminescence, virulence, biofilm formation. Quorum sensing can occur within a single bacterial species as well as between diverse species, and can regulate a host of different processes, in essence, serving as a simple communication network. A variety of different molecules can be used as signals. Common classes of signaling molecules are oligopeptides in Gram-positive bacteria, N-Acyl Homoserine Lactones (AHL) in Gram-negative bacteria, and a family of autoinducers known as autoinducer-2 (AI-2) in both Gram-negative and Gram-positive bacteria.
Quorum sensing is regulation of gene expression in response to changes in cell-population density. The signal molecules which is secreted by bacteria, known as "autoinducers". Gram-negative bacteria use acylated homoserine lactones as autoinducers, and Gram-positive bacteria use processed oligo-peptides to communicate. Quorum sensing process also help in symbiosis, virulence, competence, conjugation, antibiotic production, motility, sporulation, and biofilm formation.
Microbial growth can be measured by direct and indirect methods of measurement. Direct methods of measurement includes Plate count(spread plate, pour plate), by Filtration, Most Probable Number(MPN), Direct microscopic count. while indirect methods of measurement includes by Turbidity, Metabolic activity and by obtaining dry weight by centrifugation
There are mainly 2 methods for measuring microbial growth : 1. direct method 2. Indirect method . DIRECT METHOD includes most probable number (MPN), Standard Plate count (SPC), Filteration , spread plate ,pour plate . INDIRECT METHOD includes cell mass, cell number , turbidity , dry weight (Centrifugation).
Microbial growth can be measured by direct and indirect methods of measurement. Direct Method includes most probable number (MPN), Standard Plate count (SPC), Filteration , spread plate ,pour plate . Indirect Method includes cell mass, cell number , turbidity , dry weight (Centrifugation).
There are different methods of counting microbial growth. These are based on different parameters of cells such as dry-weight and wet-weight measurement, absorbance ( by using a spectrophotometer), cell plate, density, turbidity, viable count (by stranderd plate count), cell count by Coulter counter, cell count by petroff hausser counting chamber.
Microorganisms attach to surfaces and develop biofilms. Biofilm-associated cells can be differentiated from their suspended counterparts by generation of an extracellular polymeric substance (EPS) matrix, reduced growth rates, and the up- and down- regulation of specific genes. Attachment is a complex process regulated by diverse characteristics of the growth medium, substratum, and cell surface.
A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular polymeric substances (EPSs).The cells within the biofilm produce the EPS components, which are typically a polymeric conglomeration of extracellular polysaccharides, proteins, lipids and DNA.Because they have three-dimensional structure and represent a community lifestyle for microorganisms, they have been metaphorically described as "cities for microbes".Microorganisms that form biofilms include bacteria, fungi and protists. One common example of a biofilm dental plaque, a slimy buildup of bacteria that forms on the surfaces of teeth. Pond scum is another example. Biofilms have been found growing on minerals and metals. They have been found underwater, underground and above the ground. They can grow on plant tissues and animal tissues, and on implanted medical devices such as catheters and pacemakers.
biofilm is compromising of microorganisms attached to a living or inert surface in an aqueous environment and surrounded in a matrix of extracellular polymeric substance.
Biofilm is a mode of microbial growth where dynamic communities of interacting sessile cells are irreversibly attached to solid substratum, as well as each other,and are embedded in a self made matrix of extracellular polymeric substance (EPS)
Biofilm formation constitutes an alternative lifestyle in which microorganisms adopt a multicellular behavior that facilitates and/or prolongs survival in diverse environmental niches. Biofilms form on biotic and abiotic surfaces both in the environment and in the healthcare setting. In hospital wards, the formation of biofilms on vents and medical equipment enables pathogens to persist as reservoirs that can readily spread to patients. Inside the host, biofilms allow pathogens to subvert innate immune defenses and are thus associated with long-term persistence. Here we provide a general review of the steps leading to biofilm formation on surfaces and within eukaryotic cells, highlighting several medically important pathogens, and discuss recent advances on novel strategies aimed at biofilm prevention and/or dissolution.Biofilm formation enables single-cell organisms to assume a temporary multicellular lifestyle, in which “group behavior” facilitates survival in adverse environments. What was once defined as the formation of a community of microorganisms attached to a surface has come to be recognized as a complex developmental process that is multifaceted and dynamic in nature. The transition from planktonic growth to biofilm occurs in response to environmental changes, and involves multiple regulatory networks, which translate signals to concerted gene expression changes thereby mediating the spatial and temporal reorganization of the bacterial cell.
Biofilms are a collective of one or more types of microorganisms that can grow on many different surfaces. Micro-organism that form biofilms include bacteria, fungi and protists. one example of a biofilm is dental plaque, a slimy buildup of bacteria that forms on the surface of teeth. They have been found underwater as well as underground. Also on plant and animal tissues and on implanted medical devices such as catheters and pacemakers
The size of Whatman Filter paper No. 4 is Circles: 27 mm to 400 mm Sheets: 38 x 114 mm to 580 x 580 mm Yes the porosity of Whatman Filter paper will change from no 4 to 1 Whatman Filter paper No.1 has the pore size of 11 μm. This filter paper is widely used for many different fields in agricultural analysis, air pollution monitoring and other similar experiments. Whatman Filter paper No.2 has the pore size of 8 μm. This filter paper requires more filtration time than 1 filter paper. This filter paper is used for monitoring specific contaminants in the atmosphere and soil testing. Whatman Filter paper No.3 has the pore size of 6 μm. This filter paper is very suitable for carrying samples after filtration Whatman Filter paper No.4 has the pore size of 20-25 μm. This filter paper has the largest pore size among all standard qualitative filter papers. It is very useful as rapid filter for cleanup of geological fluids or organic extracts during experiment.
Whatman Filter paper No.4 has the pore size of 20-25 μm.And as the Whatman filter paper no. increases from 1 to 4 porosity of the filter paper also increases.
archaea do not have peptidoglycan layer on their cell wall but they do contain pseudopeptidoglycan which is similar to peptidoglycan which contains different sugar in the polysaccharide chain. the other types of archaea may also have the cell wall composed of polysaccharide, glycoproteins or pure proteins. while archaea lack peptidoglycan, a few contain a substance with a similar structure known as pseudomurein. Instead of NAM, it contains N-acetylalosaminuronic acid (NAT) linked to NAG, with peptide interbridges to increase the strength. The bacteria which has the additional S layer in their structure, but here in archaea the S layer is the part of the cell wall and sometimes be the only S layer a pert of the cell wall. In some of the archaeal cell methanochondroitin may also be the part of the cell wall similar to the connective tissue component chondroitin found in vertebrates. so archaea lacks the peptidoglycan layer but it has the other components to fulfill the requirement.
Hyperthermophiles are adopted to Hot Environment by their physiological and Nutritional requirements. As a consequence,cell components like DNA , protiens , nucleic acid and membrane are stable and even function best at Temperatures around 100 degree celsius.
Hyperthermophiles are a subset of extremophiles within the domain Archaea. An optimal temperature for the existence ofStanford researchers show that a protein in a microbe's membrane helps it survive extreme environments. ... Scientists had known that this group of microbes – called archaea – were surrounded by a membrane made of different chemical components than those of bacteria, plants or animals
Generally, microorganisms with an optimal growth temperature between 60 and 80 degree Celsius are designated as thermophiles, whereas those growing at temperatures of greater than 80 degree Celsius are referred to as hyperthermophiles, which are found in the three domains of life, archaea, bacteria, and eukarya, but the majority are archaea and bacteria. Nucleic acids are heat-labile macromolecules. At temperatures typical for hyperthermophiles, they are susceptible to denaturation and hydrolysis. Stable RNAs are protected against denaturation in hyperthermophiles by a high GC content and by nucleotide modifications which stabilize their secondary and tertiary structures. Methylation of 2’OH can also be involved in the protection of stable RNA against hydrolysis of the phosphodiester bonds. All hyperthermophiles contain a unique enzyme reverse gyrase, which can modify DNA topology. Reverse gyrase is the only protein that is specific for hyperthermophiles. Although the precise role of reverse gyrase is still unknown, this enzyme is probably essential for life at extremely high temperatures.
Nucleic acids are heat-labile macromolecules. At temperatures typical for hyperthermophiles, they are susceptible to denaturation (unwinding of DNA double helices and RNA hairpins) and chemical degradation (hydrolysis). Stable RNAs areprotected against denaturation in hyperthermophiles by a high GC content and extensive nucleotide modifications which stabilize their secondary and tertiary structures. Methylation of 2’OH can also be involved in the protection of stable RNA against hydrolysis of the phosphodiester bonds. In contrast to RNA, intracellular DNA is intrinsically stabilized against global denaturation by the existence of topological links between the two DNA strands, explaining why the genomic DNA of hyperthermophiles is not specifically GC rich. However, DNA is susceptible to depurination and cytosine deamination at high temperature. Furthermore, depurination can induce DNA breakage and subsequent denaturation.Hyperthermophilic Archaea are highly radioresistant, indicating very efficient DNA repair mechanisms.All hyperthermophiles contain a unique enzyme, reverse gyrase, which can modify DNA topology. Comparative genomic analysis reveals that reverse gyrase is the only protein that is specific for hyperthermophiles. This enzyme is probably essential for life at extremely high temperatures.
Hypo thermophiles is the organism which are adapted to grow at even 85 degree Celsius to 113 degree Celsius. the detailed study of the enzymes which were purified from the hyper thermophiles indicated that it has a few critical amino acid substitutions which increases the protein stability. it includes the formation of ion pairs, increase in the hydrogen bonding and steric hinderance of a chain flexibility. The DNA has only four deoxyribonucleotides. As the G-C base pairing has three bonds while the A-T bonding has 2 bonds. The melting point is higher of GC then the AT. if the concentration of the GC is more in the strand than the AT then the Melting point anyhow increases and is prevented from destroying even at the high temp.
How to ensure that the same species of Microbe mentioned in Probiotics label is Actually only present in the Product and other Opportunistic microbes are Absent?
Urvi Deria(20mmb006) 1.The assessment of species identity by macroscopically, microscopically and physiologically by observing morphology of the colony, gram staining technique and various biochemical tests. 2.Genetic level tests.
1. Conventional phenotypic approaches for the identification of probiotics strain. It involves Analytical Profile Index tests, Microscopic analysis, biochemical tests. 2.Molecular approaches for strain identification It involves Sequence analysis of the partial or complete 16S ribosomal RNA (rRNA) gene of the strain. Other than these DNA Fingerprinting methods (AFLP, RAPD, etc) can also be used for identification of probiotics strain. So by performing these technique we can make sure that the same microorganisms are used in the probiotics product or any other.
many stains contain proteins, the manufacturers of laundry detergents include subtilisin in their product. Subtilisin is 274 amino acids long, and one of these, the methionine at position 222, lies right beside the active site of the enzyme. This is the site on the enzyme's surface where the substrate is bound, and where the reaction that is catalyzed by the enzyme takes place. In this instance the substrate is a protein in a stain, and the reaction results in the breaking of a peptide bond in the backbone of the protein. Unfortunately, methionine is an amino acid that is very easily oxidized, and laundry detergents are often used in conjunction with bleach, which is a strong oxidizing agent. When used with bleach, the methionine in subtilisin is oxidized and the enzyme is inactivated, preventing the subtilisin from doing its work of breaking down the proteins present in food stains, blood stains, and the like.
To overcome this problem, genetic engineering techniques were used to isolate the gene for subtilisin, and the small part of the gene that codes for methionine 222 was replaced by chemically synthesized DNA fragments that coded for other amino acids. The experiment was done in such a way that nineteen new subtilisin genes were produced, and every possible amino acid was tried at position 222. Some of the altered genes gave rise to inactive versions of the enzyme, but others resulted in fully functional subtilisin. When these subtilisins were tested for their resistance to oxidation, most were found to be very good (except when cysteine replaced methionine: It too is easily oxidized). So now it is possible to use laundry detergent and bleach at the same time and still remove protein-based stains. This type of gene manipulation, which has been called "protein engineering,"
By altering its various factors like catalytic activity, substrate specificity, pH factor etc. And Protein engineered variants of subtilisin are used to increase catalytic activity of detergent so the rate of reaction going to be increased.
Yeast works as leavening agent means it causes the dough to rise,expand and makes it softer.it also ferments the sugar present in dough and converts into carbon dioxide.
Yeast work by serving one of the leavening agent in the purpose of fermentation ,which is essential in making breads. The purpose of many leavener is to produces the gas that makes bread rise.yeast does this by feeding on the sugars in flour,and expelling carbon dioxide in the process.as the yeast feed on the sugar,it produce carbon dioxide with no place to go but up,the gas slowly fills the balloon . A very similar process happens in bread rises. Carbon dioxide from yeast fills thousands of balloon like bubbles in dough.once the bread has baked,this is what gives a loaf its airy texture. Two types of Yeats are used in bread making: regular acive dry and instant yeast( also known as fast rising, rapid rise,quick rise, and or bread machine yeast . This two types of dry yeast used interchangeably tha advantage of rapid rise is the rising time is half that of the active dry and it only need one rising.
As bread dough is mixed and kneaded, millions of air bubbles are trapped and dispersed throughout the dough. Meanwhile, the yeast in the dough metabolizes the starches and sugars in the flour, turning them into alcohol and carbon dioxide gas. This gas inflates the network of air bubbles, causing the bread to rise.
Yeast is used for the leavening of bread. Yeast uses the sugars and oxygen in dough to produce more yeast cells and carbon dioxide gas. This is called multiplication. The carbon dioxide makes the dough rise which gives the bread a light and spongy texture. Yeast also works on the gluten network. The by-products of "fermentation", or rising, give bread it's characteristic flavour and aroma. The yeast continues to grow and ferment until the dough reaches around 46°C at which temperature yeast dies.
Yeast is most commonly used in baking bread and bakery products .Yeast is used as leavening agent for Bread. Yeast uses the sugar and oxygen in dough to produce more yeast cells and carbon dioxide gas. The carbon dioxide makes the dough rise which gives the bread light and spongy texture.
when we add yeast in our flour it breaks the large starch molecules into sugar and that will produce carbon dioxide and ethyl alcohol which make the air bubbles and due to that bubbles bread dough will grow and become spongy.
when the yeast is added to the flour and the water mixture, the yeast breaks the large starch molecules into simpler sugars and during this process, it produces carbon dioxide and ethyl alcohol which make the air bubbles that cause the bread dough to grow. it just not add only air bubbles, but also flavors the dough as it break down the tasteless starch molecules into the simpler sweet sugars. the production of ethyl alcohol also somehow add the flavor to the food. when the fermentation process continues for more than days it somehow adds an acidic element to the bread.
mostly yeast use in bread production because they can form dough and dough is helps in texture of bread.Once the bread has baked, this is what gives the loaf its airy texture. Yeast-mediated dough fermentation is an important phase in the bread making process. The fermentative performance of yeast cells during fermentation is of critical importance for final bread quality, since yeast cells produce CO2 and other metabolites that have an influence on dough rheology and bread texture, volume, and taste.
We can ensure that the same species of microbes mentioned on label is actually present in product and not other species through in vitro test of probiotic microbial strains , by their site of action for instance if microbe mentioned on label of probiotic is for intestine it will definitely act on its target and not on other place in body so by this we can ensure mentioned microbe by its site of action. By gram staining we can analyse.
In 1960, Schweizerischer Ferment AG was the first ones to introduce enzyme in detergent industry. The company (takenover in 1967 by Novo) marketed Protease B from Bacillus subtilis in 1958, leads to the first introduction of proteolytic enzymes in a detergent in 1959. In 1960, new enzyme product was named Alcalase (subtilisin) , Novo’s first detergent enzyme produced by fermentation.In 1963, a Dutch firm launched the detergent Bio-tex, which contained Alcalase. Side effect:In 1969, According to one article, some workers at a British detergent factory had developed an allergy after inhaling concentrated enzyme dust , as Consumers can be exposed to Subtilisins via the respiratory route during the task of dispensing detergent products in the washing machine or laundry and According to (HERA project) Human Health Assessment also,The key health concern identified for Subtilisin is respiratory (Type 1) allergy.
The first company to introduce Enzyme based detergent was the Schweizerischer Ferment AG. The company marketed Protease B from Bacillus subtilis in 1958.
Probiotics are a combination of live beneficial bacteria and/or yeasts that naturally live in your body. Bacteria is usually viewed in a negative light as something that makes you sick. However, you have two kinds of bacteria constantly in and on your body — good bacteria and bad bacteria. Probiotics are made up of good bacteria that helps keep your body healthy and working well. This good bacteria helps you in many ways, including fighting off bad bacteria when you have too much of it, helping you feel better.
For a microbe to be called a probiotic, it must have several characteristics. These include being able to:
Be isolated from a human.
Survive in your intestine after ingestion (being eaten).
Have a proven benefit to you.
Be safely consumed.
The use of probiotics is not only limited to intestines but also it can be used in
Gut.
Mouth.
Vagina.
Urinary tract.
Skin.
Lungs.
The main function of probiotics is to maintain the check on bad or pathogenic microorganisms that can enter our body through different routes and if we are feeling healthy by the use of different probiotics then we can say the particular probiotics used are effective probiotics also help in the formation of vitamin and help in the absorption of certain medications
Most common probiotics are
Yogurt.
Buttermilk.
Sourdough bread
Cottage cheese.
Kombucha.
Tempeh.
There are also certain risk regarding the use of probiotics that may include
Developing an infection.
Developing a resistance to antibiotics.
Developing harmful byproducts from the probiotic supplement.
The minamata disease is a disease of the nervous system. It is caused by methylmercy. Minamata disease was first discovered in the city of minamata, kumamota, japan in 1956. It was caused by the release of methylmercy in the industrial wastewater from a chemical factory owned by the Chisso corporation. Minamata disease occurred in humans who ingested fish and shellfish contaminated by methylmercy.
Minamata disease sometimes referred to as Chisso-Minamata disease is a neurological disease caused by severe mercury poisoning. Minamata disease was first discovered in the city of Minamata, Kumamoto Prefecture, Japan, in 1956. It was caused by the release of methylmercury in the industrial wastewater from a chemical factory owned by the Chisso Corporation, which continued from 1932 to 1968.It has also been suggested that some of the mercury sulfate in the wastewater was also metabolized to methylmercury by bacteria in the sediment.This highly toxic chemical bioaccumulated and biomagnified in shellfish and fish in Minamata Bay and the Shiranui Sea, which, when eaten by the local population, resulted in mercury poisoning.
Minamata disease also called as Chisso Minamata disease is a neurological disease which was burst due to the poisoning of mercury. it was first discovered in Minamata City in Kumamoto prefecture japan in 1956. it was bursted due to the release of methylmercury in the industrial waste water from the chemical factory. This chemical got accumulated in the marine fishes which were then eaten by the locals resulted in the mercury poisoning. symptoms include ataxia, numbness in the hands and in the feet, general muscle pain or weakness, narrowing in the field of the vision and damage in the hearing and in the voice box too which made the harsh sound.it was also observed that the disease was also affecting the fetus in the womb which was resulting into a non healthy child in future. the cats were also infected with this disease and were called to be known as "DANCING CAT FEVER".
Minamata disease in Japan is the most famous case of methylmercury food poisoning. The first patient was officially notified to the local Public Health Center in May 1, 1956. The source and transmission mode is contaminated fish and shellfish. The etiologic agent is methylmercury, a by-product of acetaldehyde production, which was discharged from the Chisso factory from 1932 until 1968. During this period, the discharge was not stopped, and no effective measures or investigations were undertaken. The target organ of methylmercury is the central nervous system. The affected patients manifest neurological signs, including paresthesia, ataxia, dysarthria, constriction of the visual field, and/or hearing difficulties. These neurological signs were observed even among residents with hair mercury content below 50 μg g−1. The affected residents manifest psychiatric symptoms (e.g., impairment of intelligence and mood and behavioral dysfunction) as well. It is also reported that the prevalence of hypertension was elevated in the affected areas. A particularly distressing aspect of the disease is that methylmercury can be transferred to fetuses. Severely affected children born with congenital Minamata disease are mental retarded and have disturbed coordination, deformities of the limbs, poor reflexes, poor nutrition and growth, and, in some cases, show other effects. Up to March 2011, 2271 patients were officially recognized as having Minamata disease, but it is estimated that the number of patients in the affected areas who exhibit neurological signs of methylmercury poisoning is in the several tens of thousands. REFERENCE: https://doi.org/10.1016/B978-0-12-386454-3.00038-5
Both have their own pros and cons. if we are considering that the patient is in the initial stage of the depression the probiotic will affect and will have more positive response in terms of the side effects of the medication while if the patient is already suffering from years probiotic will not anyhow give a very rapid boost to the treatment while the antidepressants may work far better than probiotic. probiotics also seemed to work best when used with the combination of other treatments like medication and psychotherapy.
We can not say that probiotics is more effective than Antidepressants or Antidepressants is more effective than probiotics. Probiotics use in primary stage of depression but they don’t replace therapy, medication, or other depression treatments. gut-brain axis (GBA) link with central nervous system and it can affect appetite, mood, or sleep habits. But in 2015 some studies suggest that GBA may be the missing link in our understanding of depression and its causes so, More research is underway on this topic in neuroscience. But probiotics not cause other side effect. Bifidobacterium longum NCC3001 use in study and scientists concluded that they may improve quality of life and reduce symptoms of depression in people with irritable bowel syndrome. Several authors suggest microorganisms as a new group of drugs named “psychomicrobiotics”. So we can say that both are effective.
REFERENCES: 1 )Evrensel, A., & Ceylan, M. E. (2015). The Gunt-Brai Axis: The Missing Link in Depression. Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology, 13(3), 239–244. https://doi.org/10.9758/cpn.2015.13.3.239 doi: 10.9758/cpn.2015.13.3.239
Bacteriocins are produced by the bacteria as a defensive mechanisms against the other bacterial strains of the same species, whereas the activity of antibiotics is broad spectrum. Antibiotics harvested from a given bacterial strain can both act against the same species strains as well as on other species too
Bacteriocins are produced on the surface of ribosomes in microbial cells , Bacteriocins producers are insusceptible to the bactericidal agents. Antibiotics are primarily secondary metabolites of the cell. Antibiotics inhibits the cell wall synthesis, inhibition of ribosome function, nucleic acid synthesis.
Bacteriocins are proteinaceous toxins produced by bacteria to kill similar or closely related species, i.e. intraspecies competition is observed here. They have narrow spectrum activity. Whereas, Antibiotics kill a broad range of organisms i.e. they can kill same species as well as different species. They have broad spectrum activity.
Bacteriocins are ribosomally-synthesized bacterial antimicrobial peptides (AMPs). It kills food spoilage/pathogenic bacteria from both Gram-positive and Gram-negative group. It forms pores in bacterial cell-membrane, resulting in dissipation of proton-motive force leading to cell death. Antibacterial action generally falls within one of four mechanisms, three of which involve the inhibition or regulation of enzymes involved in cell wall biosynthesis, nucleic acid metabolism and repair, or protein synthesis, respectively. The fourth mechanism involves the disruption of membrane structure. Many of these cellular functions targeted by antibiotics are most active in multiplying cells.Effective against prokaryotic bacterial cells and eukaryotic mammalian cells.
Bacteriocins restrict their activity to the strains of species related to the producing species and particularly to strain of the same species while the activity of the antibiotics is in the broad spectrum. they inhibit the cell wall synthesis, cell membrane function, protein synthesis etc while bacteriocins also adapts to the same inhibition but works in the respective surrounding of the species while the antibiotics work in a far range.
In case of animal or plants the growth is about increase in size but in microorganisms its about increase in number of organisms so in zoology and botanical specimen it is about growth of the cell and growth of organisms,since in microbiology the individual is so small that is bacteria we need to see in population level otherwise it become difficult but you can still count microorganism in TDs form.
Microbiology is the study of all living organisms that are too small to be visible with the naked eye. This includes bacteria, archaea, viruses, fungi, prions, protozoa and algae, collectively known as 'microbes'. As the size of microraganism is so small so the growth here is measured by the increase in cell number. Macrobiology is the branch of biology that studies large living organisms (termed Macro organisms) that can be seen by the naked eye. So here the growth is measured in terms of increase in cell mass or size.
Microbiology is the study of all living organisms which are so small that cannot be seen with the naked eye , It is the branch of science that deals with microorganisms. Macrobiology is the branch of biology that studies large living organisms that can be seen with naked eye. Macrobiology is the opposite of Microbiology.
Macrobiology is the branch of biology that studies large living organisms (termed Macro organisms) that can be seen by the naked eye,growth for multicelluar organisms is typically measured in terms of the increase in size of a single organism whereas Microbiology is the study of all living organisms that are too small to be visible with the naked eye. microbial growth is measured by the increase in population, either by measuring the increase in cell number or the increase in overall mass.
UV radiations are lethal to most of the microorganisms and hence applied to inactivate the microorganisms so that they do not reproduce and multiply. The use of UV is not very frequent, but it has a great potential to be used instead of any other processing techniques to preserve the solid and liquid foods. The reason to its limited application is due to its low penetration power. Since, it has low penetration power it will be useful only for surface application rather than complete preservation and sterilization.
The ultraviolet radiation have limited application because ultraviolet light limits its use to surface application . The radiation is not very penetrating so the organisms to be killed must be directly exposed to the Ray's. UV light is effective for microorganisms not for chemicals. UV light can damage human eye,and prolonged exposed can cause burns and skin cancer so its affect workers who works in food industry UV light does not delete but only breaks.
Generally, foods are thermally processed to destroy the vegetative microorganisms for food preservation. However, only thermal treatment triggers many unwanted biochemical reactions, which leads to undesirable sensorial and nutritional effects. Therefore, a number of nontraditional preservation techniques are being developed to satisfy consumer demand with regard to nutritional and sensory aspects of foods. Ensuring food safety and at the same time meeting such demands for retention of nutrition and quality attributes has resulted in increased interest in emerging preservation techniques. The radiation techniques like UV, Gamma have been widely studied and, like most food processing techniques, can induce some changes that are able to modify the chemical and nutritional characteristics on foods. These changes are dependent on some factors such as the radiation dose, the constitution of the irradiated food, the type of packaging, and how it was processed, besides the variables of the process as temperature and oxygen saturation on the atmospheric. BUT there are some limitations. According to the research, UV-light treatment has been shown to be able to significantly alter vitamin content in milk samples when compared to the traditional pasteurizing process. However, these methods are considered safe and effective, according to several agencies such as the Food and Drug Administration (FDA).
Temperature that affects the storage stability of food temperature at which food is stored is very critical to shelf life. United States Department of Agriculture, USDA, states that for every 10.8 degrees in temperature rise you decrease the shelf life of stored food by half. The best range for food storage is a constant temperature between 40-60 degrees.
1. Moisture - For long term storage foods should have 10% or less moisture content. It is recommended to remove moisture when storing foods.
2. Oxygen - Foods store best when oxygen free. Removing oxygen will prevent oxidation of compounds in foods.
3. Temperature - The temperature at which food is stored is very critical to shell life. Avoid freezing temperatures.
4. Light - light a form of energy that can degrade value of foods . Store food in dark areas.
5. Container - Store foods in food grade plastic, metal, or glass containers indicating that the container does not contain chemicals that could be transferred to food and harmful to your health.
1. Temperature plays a very critical role in the storage stability. it is stated that 10.8 degree rise in temp can decrease the shelf life by half. the food ca be best stored at 40 to 60 degrees Celsius. 2. moisture - while storing for the long term it is very necessary to remove the moisture. 3. oxygen - food is stored for long term at a very best when the oxygen is removed as the removal of the oxygen prevents the oxidation of compounds in the foods. 4. light - light can degrade the food so it is best to store food in dark rooms. 5. container - always store the food in a good plastic quality or a metal/glass container. it should be ensured that the low quality plastic and the metals can transfer the chemicals into food which anyhow lowers the taste of the product and can be harmful to your health. the best storage container for food is air tight containers.
There are four factors that affect food storage, which are temperature, moisture, atmosphere and container choice. 1} Temperature greatly affects food storage life. For every 10 degrees-C, shelf life will halve (hotter) or double (cooler). 2} The moisture content of the food itself (some exceptions including ‘canned’ or ‘home canned’, or other sealed processing). Moisture in the storage environment. For long-term storage of grains, dehydrated foods, and other ‘dry foods’, drier is better. For example, grains should maintain a moisture content of 10% or less. 3}Earth’s atmosphere contains about 78% nitrogen and 21% oxygen. Oxygen oxidizes many of the compounds in food and reduces it’s shelf life over time. Bacteria, one of several agents which make food go rancid also needs oxygen to grow. For maximum shelf life, foods should be stored in an oxygen free environment. 4}Common sealing methods/containers include vacuum sealed bags (Food Saver), sealed Mylar bags, commercially sealed cans or jars, home-canned, sealed food storage buckets/pails.
Temperature: The temperature at which food is stored is very critical to shelf life. The best range for food storage is a constant temperature between 40-60 degrees. Avoid freezing temperatures.
Moisture: It is recommended to remove moisture when storing foods. For long-term storage, foods should have a 10 percdent or less moisture content.
Oxygen: Foods store best when oxygen free.
Light: Light transfers energy to the food products causing them to degrade in nutrition and appearance. Store food in dark areas.
Container: Store foods in food-grade plastic, metal or glass containers indicating that the container does not contain chemicals that could be transferred to food and be harmful to your health.
Some environmental factors which affect the food storage stability like 1. Temperature and also sometimes in certain conditions packaging material also affects the temperature of food.
2.gas atmosphere / oxygen Basically atmospheric oxygen has harmful effects on nutritive quality of food and because of that sometimes lipid oxidation cause loss of vitamins.
3.light Many deteriorative changes in food are started by light and the intensity of light and length of exposure are main factors in the production of discoloration and flavour defects in food.
Also some chemical reaction affects the food storage like aldehyde and ketone which are more unstable from autooxidation, sometimes cause painty,fatty,candle like flavour in food.
Temperature: The temperature at which food is stored is very critical to shelf life. United States Department of Agriculture, USDA, states that for every 10.8 degrees in temperature rise you decrease the shelf life of stored food by half. The best range for food storage is a constant temperature between 40-60 degrees. Avoid freezing temperatures.
Moisture: It is recommended to remove moisture when storing foods. For long term storage foods should have a 10% or less moisture content.
Oxygen: Foods store best when oxygen free. Removing oxygen will prevent oxidation of compounds in foods. Ways to remove oxygen:
Displacing oxygen – Purge air from product with an inert gas (nitrogen). Dry ice is often used giving off carbon dioxide gas which displaces oxygen. Oxygen absorber – Air contains about 78% nitrogen and 21% oxygen, leaving about 1% for the other gasses. If the oxygen is absorbed, what remains is 99% pure nitrogen in a partial vacuum. Light: Light, a form of energy that can degrade the food value of foods. Store food in dark areas.
Shelf date is the “best if used by” date meaning that you are getting most of the original taste and nutrition. The “life sustaining shelf life” date means the length of time that food is still edible.
Habitat and Niche are closely related terms having a thin line of Difference. Niche is the specific role of any particular species plays in an ecosystem. whereas Habitat is the physical place where any particular species lives and adapts to the environmental conditions. Eg - mountains or Grassland.
A habitat is a natural environment where a particular organism lives and utilizes the resources of that place for their survival, food, protection, shelter and mating. whereas niche is a functional role and position of a species in its environment that describes how the species responds to the resources and competitors or predators
A habitat is the general place where an organism lives and a niche is the range of physical and biological conditions in which a species lives and the way the species obtain what it needs to survive and reproduce.
habitat :Habitat can be defined as the natural environment of an organism, the type of place in which it is natural for it to live and grow. Niche :It encompasses both the physical and environmental conditions it requires and the interactions it has with other species.
Habitat is a natural place where an organism gets all requirements i.e. all necessary components biotic and abiotic factors which unit to form a suitable and survivable place. while niche is a particular place within habitat where an organism performs all its activity and interaction with other organism.
Habitat is not specific to species but Niche is specific to a particular species
A habitat is a natural environment where a particular organism lives and utilizes the resources of that place for its survival, food, shelter, protection, and mating. The term habitat has been derived from the Latin word, ‘habitāre’ which means ‘to inhabit’. The habitat of an organism is characterized by its physical and biological characteristics. The physical factors include the nature of the soil, availability of land, sunlight, temperature, and climatic conditions. The biological factors include the availability of food and the absence or presence of predators. Niche is the functional role and position of a species in its environment that describes how the species responds to the distribution of resources and competitors or predators. Like habitat, the niche is also determined by both the biotic and abiotic factors of the particular environment. However, a niche represents the interactions of a population with these factors and its effect on the environment and other organisms within the environment. For example, a population in an environment utilizes the resources and breeds to produce more organisms which then increases the resources for the predators. Reference: https://microbenotes.com/habitat-vs-niche/
A habitat is about a area where different species lives while a niche is an ideology that how an organisms lives. Habitat is a physical place while niche is activity which is performed by organisms.
Habitat is the general place where an organism lives and a niche is the functional role and position of a species in its environment that describes how species responds to the distrubution of resources and competitors.
A habitat defines the interaction of organisms with the other factors, which can be living or non-living, while niche describes how that specific organism is linked with its physical and biological environment. Habitat is the part of the ecosystem, while niche plays an important role in the formation of an ecosystem.
Habitat is a physical address of a particular organism or species,a place where organisms live,while Niche is the functional address and it includes habitat also,it shows where a particular species live and what it is doing there (it shows abiotic and biotic association with the environment.It shows role of an organism in its ecosystem).
Algae are autotrophic organisms and they have chlorophyll. They are O2 producing photosynthetic organisms that have evolved in and have exploited an aquatic environment. The study of Algae is known as Algology or phycology.
In Algae the plant body shows no differentiation into root, stem or leaf or true tissues. Such a plant body is called thallus. They do not have vascular tissues. The sex organs of this group of kingdom plantae are not surrounded by a layer of sterile cells.
1. Algae include a group of about of 30,000 species which are generally aquatic (both freshwater & marine).
2. Their size varies from microscopic forms to the filamentous forms. 3. All the members of algae are Chlorophyllus, non-vascular thallophytes.
4. They contain chlorophyll a, carotenes and xanthophylls. Additional pigments occur in specific groups. 5 Vegetative and asexual modes of reproduction are very common. Asexual spores are of two types: mitospores and meiospores. They are easily dispersed in aquatic habitat, actively, if motile and passively by water currents, if non-motile.
6.Sex organs are non jacketed. . Different types of life cycle occur, viz., Haplontic (haploid phase dominant), Diplontic (diploid phase dominant) and Haplodiplontic (both haploid and diploid phase equally dominant).
These are simple living organisms that have chlorophyll. They are the simplest forms of producers in a food chain. They can be single-celled or multicellular. Known to be largely aquatic, algae have a thalloid structure, without much differentiation. You can find algae in a variety of habitats such as freshwater, marine, moist stones, wood, and even soil. A mutual association is found in between fungi and algae, leading to an entirely new organism called the lichens.
1. They are mostly chlorophyll containing autotrophic thalloid plants. 2. They occurs in a variety of habitats, but majority of them are aquatic. 3. They store food material in the form of starch. 4. They have mostly unicellular sex organs without a jacket of sterile cells around them. Jackets cells,if presents have different initials. There is a progressive complexity in reproduction. 5. Embryo is not formed after gametic union. 6. They shown distinct alternation of generation.
1.At the beginning of the history of life, algae changed the atmosphere of the planet by producing oxygen, thus opening the way for the evolution of eukaryotic organisms so we can say that algae is also responsible for evolution. 2. 3.5 billion years ago prokaryotic life began on the planet in the absence of oxygen. The cyanobacteria (blue–green algae) arose and began releasing oxygen into the atmosphere as the waste product of chlorophyll a-mediated photosynthesis. 3.the production of oxygen by algae (about 50% of all oxygen production) is another reason to say "our lives depend on algae". 4.algae are the main producers on which aquatic ecosystems depend and they maintain food chain 5.They are one of the main sources of sustainable biofuel production and CO2 consumption.Finally, the algae that gives us the air, the food and the fuel 6.algae are also a source of active pharmaceutical compounds which may be used against drug resistant strains of bacteria, viruses like herpes simplex and AIDS and cancers. 7.The total biomass of the world's algae is just one tenth of the biomass of all other plants, the efficiency of algae is impressive. 8.Red algae are the source agar and carrageenans and they use in hundreds of products, including ice cream, beer, soy milk and pet food, among others. 9.Porphya red seaweed is also harvested as Nori and is dark purple - reddish wrap used in sushi around the world. 10.Brown algae are often major components of the rocky intertidal zone and therefore are exposed to low tide and must withstand both desiccation and, in many cases, full force of major wave action when the tides come in.
reference: Chapman, R. L. (2013). Algae: the world’s most important “plants”—an introduction. Mitigation and Adaptation Strategies for Global Change, 18(1), 5-12
1. The algae traditionally are viewed as photosynthetic eukaryotic microorganisms that do not exhibit tissue differentiation and do not develop from embryos supported by maternal tissue.
2. They can be unicellular or multicellular. Multicellular algae may be filamentous. Unicellular algae may be spherical,rod shaped,club shaped.
3. Algae store various products within their cells, often in vacuoles or in association with the pyrenoid regions of chloroplasts.
4. Algae reproduce asexually or sexually. Asexual reproduction occurs by fragmentation, spore formation and binary fission. Sexual reproduction involves fusion of gametes to form zygote.
5. The algae is an important part of ecosystem. It serves as producers. It can used as food supplements. Some algal species produce agar agar.
1. Algae include a group of about of 30,000 species which are generally aquatic (both freshwater & marine). 2. Their size varies from microscopic forms to the filamentous forms. 3. All the members of algae are Chlorophyllus, non-vascular thallophytes. 4. They contain chlorophyll a, carotenes and xanthophylls. Additional pigments occur in specific groups. 5. Mucilage protects algal thallus from desiccation and from epiphytic growth. 6. Vascular & mechanical tissues absent. 7. Vegetative and asexual modes of reproduction are very common. Asexual spores are of two types: mitospores and meiospores. They are easily dispersed in aquatic habitat, actively, if motile and passively by water currents, if non-motile. 8. Sex organs are non jacketed. 9. Sexual reproduction usually occurs towards the end of growing season. 10. Embryonic stage absent which is a characteristic feature of thallophyta. 11. Sexual reproduction involves isogamy, anisogamy and oogamy in different groups. 12. Different types of life cycle occur, viz., Haplontic (haploid phase dominant), Diplontic (diploid phase dominant) and Haplodiplontic (both haploid and diploid phase equally dominant).
Samples are collected from different sites of hot spring in sterile vacuum flasks which are able to keep the temperature constant. The samples were brought in the laboratory within 2 hours of collection for processing. Physical and chemical properties of water samples are first tested and presence of heavy metals and nutrients are also determined. For isolation the sample is first initially inoculated under sterile conditions on both nutrient agar and thermus agar media. The nutrient agar (NA) is general media which allows the growth of a wide range of microorganism whereas thermus agar (TA) medium is specific for growth of thermophilic bacteria only. After culturing, the plates are incubated at different temperatures 40oC, 50oC, 60oC 70oC, 80oC and 90oC for 48-72 hrs.
Ref. - Research Article- Thermophiles: Isolation, Characterization and Screening for Enzymatic Activity Jean Bosco Nshimiyimana1,2, Sujan Khadka*2,3, Esther Muhindo Mwizerwa1 , Nathan Akimana1 , Sanjib Adhikari3 , Antoine Nsabimana1
We can grow the bacteria at temperatures as high as 65-70 C to count, however we can use Thermus agar which is resistant to higher temperatures. It depends on which kind of thermophilic bacteria we have. If we have Thermus sp, Bacilli or other kind we should use different special Media
thermophilic bacteria are the microbes that mostly inhabit hot springs, live and survive in temp above 80 degree celsius. thermophilic micro0rganisms have gained world wide importance due to their tremendous potential to produce thermostable enzymes that have wide use in industries and pharmaceuticals. the soil sample from the hot spring areas is collected and are cultured in the nutrient agar medium. the tubes are incubated at 50 degree for 12 hours and then the culture of the bacteria is streaked into the another fresh medium and after the growth it is heated in more temp to see the tolerance at higher temp. the thermus agar is used as it can withstand with the temp. after isolating the bacteria with the staining procedure it is studies further whether it is gram positive or gram negative, the shape of the bacteria is also studied.
Bacteria under high hydrostatic pressure regulate the fluidity of membrane phospholipids to compensate for pressure gradients between the inside of the cell and the environment.
Barophiles are defined as organisms which grow optimally or preferentially at pressures greater than atmospheric pressure (0.1 MPa). The lipid compositions of barophilic bacterial strains which contained docosahexaenoic acid (DHA [22:6n-3]) were examined, and the adaptive changes of these compositions were analyzed in response to growth pressure. In the facultatively barophilic strain 16C1, phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) were major components which had the same fatty acid chains. However, in PE, monounsaturated fatty acids such as hexadecenoic acid were major components, and DHA accounted for only 3.7% of the total fatty acids, while in PG, DHA accounted for 29.6% of the total fatty acids. In response to an increase in growth pressure in strain 16C1, the amounts of saturated fatty acids in PE were reduced, and these decreases were mainly balanced by an increase in unsaturated fatty acids, including DHA. In PG, the decrease in saturated fatty acids was mainly balanced by an increase in DHA. Similar adaptive changes in fatty acid composition were observed in response to growth pressure in obligately barophilic strain 2D2. Furthermore, these adaptive changes in response were also observed in response to low temperature in strain 16C1. These results confirm that the general shift from saturated to unsaturated fatty acids including DHA is one of the adaptive changes in response to increases in pressure and suggest that DHA may play a role in maintaining the proper fluidity of membrane lipids under high pressure.
High pressure and low temperature in deep-sea environments theoretically decrease the fluidity of lipids and possibly depress the functions of biological membranes . Thus, barophiles seem to have some mechanism which allows their lipids to adapt to deep-sea environments. Recent research on the physiology and molecular biology of deep-sea barophilic bacteria has identified pressure-regulated operons and shown that microbial growth is influenced by the relationship between temperature and pressure in the deep-sea environment.
A piezophile, also called a barophile, is an organism which thrives at high pressures, such as deep sea bacteria or archaea. They are generally found on ocean floors, where pressure often exceeds 380 atm (38 MPa). Some have been found at the bottom of the Pacific Ocean where the maximum pressure is roughly 117 MPa. The high pressures experienced by these organisms can cause the normally fluid cell membrane to become waxy and relatively impermeable to nutrients. These organisms have adapted in novel ways to become tolerant of these pressures in order to colonize deep sea habitats. One example, xenophyophores, have been found in the deepest ocean trench, 6.6 miles below the surface.
barophile is an organism which grow at higher pressure than atmospheric pressure. they grow rapidly at low temp and high pressure in deep sea environments which theoretically decrease the fluidity of lipids and the functions are also depressed of the membranes. barophiles have adapted to the mechanism which allows their lipids to adapt to deep see environments. it is been observed that increase in the pressure eventually increases the level of unsaturated fatty acids. it is also observed that deep marines bacteria have the PUFA which eventually is not present in the terrestrial bacteria. PUFA such as docosahexaenoic acid DHA and eicosapentaenoic acid EPA are found in the lipid layer of the bacteria. PUFA have the low melting point and they may assist in maintaining the proper fluidity of membrane lipids so that they can adapt to the deep sea environment.
Two strains of obligately barophilic bacteria were isolated from a sample of the world’s deepest sediment, which was obtained by the unmanned deep-sea submersible Kaiko in the Mariana Trench, Challenger Deep, at a depth of 10,898 m. From the results of phylogenetic analysis based on 16S rRNA gene sequences, DNA-DNA relatedness study, and analysis of fatty acid composition, the first strain (DB21MT-2) appears to be most highly similar to Shewanella benthica and close relatives, and the second strain (DB21MT-5) appears to be closely related to the genus Moritella. The optimal pressure conditions for growth of these isolates were 70 MPa for strain DB21MT-2 and 80 MPa for strain DB21MT-5, and no growth was detected at pressures of less than 50 MPa with either strain. This is the first evidence of the existence of an extreme-barophile bacterium of the genus Moritella isolated from the deep-sea environment.
High pressure cause reducing the fluidity in cell membrane by increasing packaging of fatty acyl chains of phospholipid. This causes gel like membrane which interferes in nutrient uptake and cell signaling.
But in barophiles (piezophiles) this is prevented by increasing the proportion of monounsaturated and polyunsaturated fatty acids in their membrane and which can not be packed as tightly as saturated fatty acids.
High hydrostatic pressure (change in conformation of cellular proteins). While pressure is in range it shows that barophiles are not able to denature the proteins and the small conformations changes cause changes or inhibition of protein function or destabilizations of protein structure. E.g. barophiles shewanella bacteria shows lower concentrations of proline residues whose cyclic side chain distrubs alpha helix and glycine residues having side chains with high conformational flexibility which also destabilize helical protein structure.
And these modification indicates overall decrease in protein flexibility and increase stability in hidh pressure environment.
chemostat is a bioreactor in which fresh medium is continuously added, while culture liquid containing left over nutrients, metabolic end products and microorganisms are continuously removed at the same rate to keep the culture volume constant ,continuously operated bioreactors where growing cells reach a steady state condition at which specific growth rate, as well as substrate and the product concentrations remain constant. In this way fastest growing bacteria can be isolated as continuously fresh medium is provided,fastest growing bacteria needs constant supply. The growth rate of fastest growing bacteria can be determined by the rate at which new medium is fed into the growth chamber.so useful for isolation.
The chemostate is an experimental apparatus where the chemical environment can be maintain static and fresh medium is added continuously and culture liquid removed by keeping culture and chemical environment constant. Fastest growing species need more nutrient compare to other species,chemostate provide continuous nutrient so it can be used for isolation of fastest growing species.
the chemostat is a bioreactor to which fresh medium is continuously added, while the culture liquid containing the leftover nutrients, metabolic end products and microorganisms are continuously removed at the same rate to keep the culture volume constant. fastest growing bacteria's requirement is more as it will need more nutrient and the accumulation of the toxic substance should also removed at the regular interval so it does not interfere in the growth cycle and chemostat is exactly functioning like that providing nutrient and removing the debris of toxic substance.
Chemostats are continuously operated bioreactors where growing cells reach a steady state condition at which specific growth rate, as well as biomass, substrate and the product concentrations remain constant. They are therefore an extremely powerful tool for the precise analysis of cell metabolism and with the miniaturization their role in biological and physiological research, and for the growth model parameters evaluation, got even higher potential. One of the first continuously operated microbioreactor had six units with a working volume of 16 nL working in parallel on a single chip. One of the main advantages enabling to monitor the programmed behavior of bacterial populations for hundreds of hours was an active approach to preventing biofilm formation. The microchemostat, where mixing was obtained by circulating flow in a microfluidic loop, operated by alternating continuous circulation with dilution and cleaning by means of a lysis buffer. The miniaturized device enabled automated culturing and monitoring of populations of 100 to 104 bacteria with instantaneous single-cell resolution.
Chemostats are an example of continuous cultures wherein the rate at which the sterile media is incoming having at least one essential nutrient in limiting concentrations is equal to the rate of removal of microorganisms along with media. thus final cell density of culture depends on the nutrient in its limiting concentrations. Rate of nutrient exchange is expressed by the dilution rate wherein D= f/V where f=flow rate in (ml/hr) and V=volume of vessel(ml). Population size and generation time are dependent on the dilution rate. In a mixed culture, as dilution rate increases generation time decreases as more nutrients are available thus energy can be conserved both for reproduction as well as metabolism and the growth rate increases thus resulting in the complete depletion of the limiting nutrient. whereas when dilution rate is too high i.e. greater than the maximum growth rate, the microorganisms are washed out before even reproducing. This happens as the competition for the nutrients arises among the microorganisms and the fastidious microorganisms having high generation time than the others is able to utilize the nutrients for both maintenance as well as reproduction thus the progeny of fastidious microorganisms survive. As for example, the dilution rate is 7 minutes-1 and the generation time of fastidious microorganisms is 6 minute-1 then their progeny survives and the rest of the microorganisms are washed out before reproduction.
A synchronous culture (organisms at same stage)obtained by manipulating environmental conditions such as by changing the temperature or adding fresh nutrients as soon as they enter to stationary phase or by centrifugation or by filtration.
Most widely used method for obtaining the synchronous culture is the helmstetter-cummings technique.
In which unsynchronized bacterial culture is filtered by cellulose nitrate filter. Tightly bound cells remain on filter while loosely bound cells are washed. The filter is now inverted and fresh medium is adding on it and flow through it.
New bacterial cell which are produced by cell division that are lightly bound with it and washed with effluent.Therefore,in effluent presented all the cell are newly formed and are at the same stage of growth. Thus the effluent which is referred as synchronous culture.
Synchronous growth can be achieved by membrane filteration technique (Helmstetter and cummings).Here, cells are implanted on a membrane filter and the membrane is subjected to reverse flow of liquid medium.By using filter of small pores bacteria of a certain size range are obtained. The smallest bacteria in a population are excluded from passing through the filter. Because the smallest bacteria are frequently the youngest bacteria, the filtering method selects for a population of bacteria that have just completed a division event. so the effluent stream only have bacteria with newborn cell.When the bacteria are suspended in fresh growth medium the population will subsequently grow and then divide at the same rate. There are some other induction method also available like induction methods also used. Temperature shocks, both hot and cold, and combinations of heat and cold have been used to induce synchrony,centrifugation, nutritional techniques such as allowing the growth medium to become depleted with respect to one of the nutrients and then transferring the organisms to fresh complete medium
External conditions can be changed, so as to arrest growth of all cells in the culture, and then changed again to resume growth. The newly growing cells are now all starting to grow at the same stage, and they are synchronized. For example, for photosynthetic cells, light can be eliminated for several hours and then re-introduced. Another method is to eliminate an essential nutrient from the growth medium and later re-introduce it
If we want all the cell to be in the same stage of their cell cycle we can obtain by using synchronous growth techniques. There are three techniques.
1.INDUCTION TECHNIQUES The most frequently employed methods for inducing synchrony involve temperature cycles (temperature shocks), light cycles, and chemical manipulations. When temperature is used to induce synchrony, the cells are subjected to alternating cold and warm periods.Little cell division occurs during the cold periods, but on entry into the warm periods, cell division commences. For example, cultures of the flagellate protozoan Polytomella agilis can be synchronized by a repetitive temperature cycle of 22 hours at 9°C followed by 2 hours at 25°C.
2.SELECTIVE TECHNIQUE: synchronous population can be selected by physical separation of cell at the same stage of cell cycle by differential filtration or density centrifugation.
3.HEMSTETTER-CUMMINGS TECHNIQUES: it is an excellent selective technique, which is based on the fact that certain bacteria stick tightly to cellulose nitrate paper. The technique involves filtering on unsynchronized culture of bacteria through a membrane filter then inverting the filter, allowing fresh medium to flow through it. After loosely associated bacteria have been washed from filter, the only bacterial cells in effluent stream of medium are those that arise through division. Hence, all cell in the effluent are newly formed and are therefore at the same stage of the cell cycle.
synchronous growth is the growth of the bacteria such that all the bacteria are at the same stage in their growth cycle. all cells in the culture will divide at the same time, will grow for a generation time, and all will divide again at the same time. thus the entire population will kept uniform with respect to the growth and division.
There are two methods from which the synchronous culture can be obtained. 1. according to the age or size by physical separation of cells. 2. a culture is manipulated by the change in the physical environment or the chemical composition of the medium to obtain a synchronously dividing culture. 1 SELECTION BY AGE AND SIZE the cells are filtered so the smallest cell pass through the filter. the smallest cells are the young cells and must go through their whole life cycle before dividing. alternatively, the largest cells which are ready to divide may be retained by a filter. The Helm Stetter-Cummings technique usually is used in which the cells are passed through membrane filter of pore size small enough to trap bacteria in the filter. the filter is then inverted, and fresh nutrient medium is allowed to flow through it. after loosely associated bacteria are washed from the filter, the only bacterial cells in the effluent stream of the medium are those which arise through division.
2. SELECTION BY INDUCTION TECHNIQUE a synchronous culture is also obtained by the use of shock treatments. these include variation in temp, starvation, exposure to light, drugs and sub lethal doses of radiation. a commonly used technique involves submitting a culture of microorganisms to single or multiple changes in temp. an exponentially growing culture at 37 degree is held for about 30 minutes in 20 degree. the lower temp retards cell division. during the interval of 30 minutes all the cell mature to the point. however, at 20 degree none divide. on sudden return of the culture to 37 degree, all the cells divide synchronously.
A synchronous or synchronized culture is a microbiological culture or a cell culture that contains cells that are all in the same growth stage. Synchronous cultures can be obtained in several ways:
External conditions can be changed, so as to arrest growth of all cells in the culture, and then changed again to resume growth. The newly growing cells are now all starting to grow at the same stage, and they are synchronized. For example, for photosynthetic cells, light can be eliminated for several hours and then re-introduced. Another method is to eliminate an essential nutrient from the growth medium and later re-introduce it. Cells in different growth stages have different physical properties. Cells in a culture can thus be physically separated based on their density or size, for instance. This can be achieved using centrifugation (for density) or filtration (for size).
nowadays we see many advertisements of bulb, ac, and other things have antibacterial property so how can they kill bacteria of surrounding is it harmfull for our skin because bacteria generally found surface of our skin ?
the intensified LED blue light excites certain molecules in harmful micro-organisms through photo-activation. Reactive oxygen species are then produced that damage and kill the harmful cells. Till date researchers have found no harmful effects on skin.
Various things like bulb, A.C. and also certain metals have antibacterial property. For example - The Syska Bactiglow is a 2-in-1 LED bulb that also works as an antibacterial bulb. It emits Ultraviolet Germicidal Irradiation (UVGI), that uses short wavelengths (safe for human exposure) to effectively kill germs and resist to grow around you. It does not emit any UV/IR radiations but only visible light, which is safe for human exposure and is photobiologically safe. The Syska Bactiglow emits light in the wavelength of 400 to 420 nm which is safe for human exposure. Research scientists have also been working in these and have found no harmful effects to humans.
Yes,recent research show that probiotic can be use as a drug delivery. Current cancer therapies have limited efficacy because they are highly toxic to both cancer cells and normal tissue. A growing body of evidence suggests that LAB(lactic acid bacteria) have chemopreventive effects, even though the magnitude of these effects (therapeutic activity) does not match that of chemical drugs. However, LAB can be used as a natural adjuvant for chemotherapy, and they can be engineered to deliver therapeutic payloads in a targeted manner. Many creative approaches have been used to exploit natural bacterial processes and/or to harness bacteria as therapy vectors and cancer cell destroyers. Some of the safety concerns associated with genetic engineering need to be overcome; however, we believe that LAB are an important new weapon in the fight against cancer and other immune diseases.
Yes,recent discovery shows certain viruses of gram-positive bacteria also use quorum sensing to communicate with each other The viruses also use short peptides as autoinducer to monitor virus population densit
Viruses that infect bacteria known as bacteriophages have surveillance mechanisms that provide information on whether to stay dormant or attack, depending on the availability of fresh victims. But researchers have long thought that these processes were passive; the phages seemed to just sit back and listen, waiting for the bacterial distress signals to reach the fever pitch before taking action.
Phages might speak only to their own kind , but they can listen in on other languages . Molecular biologist Bonnie Basler and her graduate students Justin Silpe have found that virus can use quorum sensing chemicals released by bacteria to determine when best to start multiplying. The virus can also use short peptides as autoinducer to monitor virus population density.
Do studying history helps us getting the idea of evolution of simple to complex living entity?
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DeleteYes, studying history will help us understand how simple to complex living entities evolved on earth, citing examples further- For evolution of viruses there are three main hypotheses
Delete1- progressive hypothesis states that viruses arose from genetic material, 2- regressive hypothesis states that viruses are remnants of cellular organisms and 3- the virus first hypothesis states that they coevolved with other cellular hosts.Viruses and bacteria share a common ancestor – a fully functioning, self-replicating cell that lived billions of years ago. From this cell, bacteria have evolved in the direction of increasing complexity( simple to complex), while viruses have gradually shed genes(complex to simple) they found they didn’t need – until they could no longer even reproduce on their own.
But like humans –bacteria evolved to become more complex, viruses became simpler.
Today, viruses are so small and simple, they can’t even replicate on their own.
Another example is size of the brain, the size is directly related to the complexity, in nearly seven million years the human brain has tripled in size. Early skulls give us evidence about the volumes of ancient brains and some details about the relative sizes of major cerebral areas.
Australopithecus afarensis, had skulls with internal volumes of between 400 and 550 milliliters, whereas chimpanzee skulls hold around 400 ml and gorillas between 500 and 700 ml.The first fossil skulls of Homo erectus had brains averaging a bit larger than 600 ml.
Early Homo sapiens had brains within the range of people today, averaging 1,200 ml or more. This is how our brains complexity increased and now has started decreasing due to our life style and various other environmental factors.
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Deleteyes, studying history can help us to get idea of evolution as life on earth was began 3.5 to 4 billion years ago and it has been evolving ever since. At first it is believed that all organisms were simple and single celled. much later multicellular organisms were evolved so if we start looking from history we can get an idea of evolution of simple to complex living entity.
DeleteConventional wisdom holds that complex structures evolve from simpler ones, step-by-step, through a gradual evolutionary process. As complexity arises, it may help an organism survive better or have more offspring. If so, it will be favored by natural selection and spread through the population. Mammals, for example, smell by binding odor molecules to receptors on nerve endings in their nose. AS we learn more about history, we would get a deep understanding about "how did the complex life evolve" or "theory of evolution". Thus, studying history helps us to understand evolution of simple to complex life entity.
DeleteYes, studying history helps us getting the idea of evolution of simple to complex living entity.
Deleteaccording to scientists first of all simple organisms exist on earth. there are many hypothesis for development of this simple organisms on earth some group of scientists believe that life came from outer space as spores while another group explained that life came from a non-cellular component such as decaying matters like mud. other some group of scientists believe life originated from non-living organic molecules like proteins and RNA and after that this simple organisms developed by endosymbiosis and become more complex living entity.
Thank you for your valuable inputs
DeleteYes, studying history will help us understand how simple to complex living entities evolved on earth The 17th century discovery of living forms existing invisible to the naked eye was a significant milestone in the history of science, for from the 13th century onward it had been postulated that “invisible” entities were responsible for decay and disease. The word microbe was coined in the last quarter of the 19th century to describe these organisms, all of which were thought to be related. As microbiology eventually developed into a specialized science, it was found that microbes are a very large group of extremely diverse organisms. Microbiology essentially began with the development of the microscope. Although others may have seen microbes before him, it was Antonie van Leeuwenhoek, a Dutch draper whose hobby was lens grinding and making microscopes, who was the first to provide proper documentation of his observations. Although his observations stimulated much interest, no one made a serious attempt either to repeat or to extend them. Leeuwenhoek’s “animalcules,” as he called them, thus remained mere oddities of nature to the scientists of his day, and enthusiasm for the study of microbes grew slowly. The early Greeks believed that living things could originate from nonliving matter (abiogenesis) and that the goddess Gea could create life from stones. Aristotle discarded this notion, but he still held that animals could arise spontaneously from dissimilar organisms or from soil. This advance in understanding was hard fought, involving series of events, with forces of personality and individual will often obscuring the facts.Darwinian evolution can be depicted as a tree, with the original organism at the base of the trunk and the myriad evolutionary changes that occur over time generating the branches and even smaller twigs at their tips. In contrast, evidence that has been accumulating since the 1970s has firmly established that microbial evolution occurs differently. The tree analogy is inaccurate when describing microbial evolution. This wider, interspecies transfer is called horizontal transfer. It is one route by which a bacterium can become resistant to one or more antibiotics. A bacterium that carries the genetic determinants for resistance to an antibiotic may be able to transfer the gene to another, unrelated bacterium, which then also becomes resistant to the antibiotic.
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ReplyDeleteThe acceptance of biological evolution, the preceding term pronounced is an essential part of the modern scientific explanation of the natural world. Most scientists and major religions in the Western World have long since incorporated it into their understanding of nature and humanity. However, some churches still maintain that there was a special and independent creation of every species and that life forms do not change through time from generation to generation. These "creationists" often share beliefs about the Judeo-Christian Bible that were widely held, even by scientists, during the early 19th century and before.Lamarck believed that microscopic organisms appear spontaneously from inanimate materials and then transmute, or evolve, gradually and progressively into more complex forms through a constant striving for perfection. The ultimate product of this goal-oriented evolution was thought by Lamarck to be humans. He believed that evolution was mostly due to the inheritance of acquired characteristics as creatures adapted to their environments. That is, he believed that evolution occurs when an organism uses a body part in such a way that it is altered during its lifetime and this change is then inherited by its offspring. For example, Lamarck thought that giraffes evolved their long necks by each generation stretching further to get leaves in trees and that this change in body shape was then inherited. Likewise, he believed that wading birds, such as herons and egrets, evolved their long legs by stretching them to remain dry. Lamarck also believed that creatures could develop new organs or change the structure and function of old ones as a result of their use or disuse.
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ReplyDeleteYes! Studying history can help us understand the idea of evolution as life on earth. Evolution is one of the greatest theories in all of science. It sets out to explain life: specifically, how the first simple life gave rise to all the huge diversity . The evolution of biological complexity is one important outcome of the process of evolution. Once simple life emerged, it gradually evolved into more complex forms, eventually giving rise to animals and plants. After simple cells first appeared, there was an extraordinarily long break – nearly half the lifetime of the planet – before complex ones evolved. In fact, it appears that simple cells gave rise to complex ones just once in 4 billion years of evolution. Thus according the theories studied , we can say that history helps us get the idea of evolution of simple to complex living entity.
ReplyDeleteYes, studying history will help us understand how simple to complex living entities evolved on earth The 17th century discovery of living forms existing invisible to the naked eye was a significant milestone in the history of science, for from the 13th century onward it had been postulated that “invisible” entities were responsible for decay and disease. The word microbe was coined in the last quarter of the 19th century to describe these organisms, all of which were thought to be related. As microbiology eventually developed into a specialized science, it was found that microbes are a very large group of extremely diverse organisms. Microbiology essentially began with the development of the microscope. Although others may have seen microbes before him, it was Antonie van Leeuwenhoek, a Dutch draper whose hobby was lens grinding and making microscopes, who was the first to provide proper documentation of his observations. Although his observations stimulated much interest, no one made a serious attempt either to repeat or to extend them. Leeuwenhoek’s “animalcules,” as he called them, thus remained mere oddities of nature to the scientists of his day, and enthusiasm for the study of microbes grew slowly. The early Greeks believed that living things could originate from nonliving matter (abiogenesis) and that the goddess Gea could create life from stones. Aristotle discarded this notion, but he still held that animals could arise spontaneously from dissimilar organisms or from soil. This advance in understanding was hard fought, involving series of events, with forces of personality and individual will often obscuring the facts.Darwinian evolution can be depicted as a tree, with the original organism at the base of the trunk and the myriad evolutionary changes that occur over time generating the branches and even smaller twigs at their tips. In contrast, evidence that has been accumulating since the 1970s has firmly established that microbial evolution occurs differently. The tree analogy is inaccurate when describing microbial evolution. This wider, interspecies transfer is called horizontal transfer. It is one route by which a bacterium can become resistant to one or more antibiotics. A bacterium that carries the genetic determinants for resistance to an antibiotic may be able to transfer the gene to another, unrelated bacterium, which then also becomes resistant to the antibiotic.
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ReplyDeleteWhy the air which passes through the petri plate does not contaminate the plate?
ReplyDeleteAfter inoculation, lid of the Petri dish is sealed with adhesive tape to prevent microorganisms from the air contaminating the culture – or microbes from the culture escaping.
DeleteBut we do not seal all the way around the edge – as oxygen
needs to get into the dish to prevent the growth of unnecessary anaerobic bacteria
Normally we don't use the tap for seal, In normal condition it is not happening.
Deletewhy?
When spreading the bacterial culture onto the dish,the lid should be minimal amount to prevent any unwanted microbes from contaminating the culture. Finally ,before the plate is incubated so that the bacteria can grow,the lid is sealed using sticky tape.
Deleteyes this is the one of the method where sticky tape is used. but when we are performing in lab we usually do not seal the plate. then how the contamination is not occuring?
DeleteIn growth curve experiment all nutrients are available and conditions are favourable, but some organisms select to go stationary phase instead of log phase Why?
ReplyDeleteThe organisms usually goes to stationary phase when the saturation level is achieved. In stationary phase usually the rate of bacterial growth is equal to the rate of bacterial cell death. the arise of stationary phase may come due to depletion of some amount of nutrient or there may be an accumulation of the inhibitory product like the organic acids.
DeleteWhat is the life span of Bacterial Cell ? How much time does Bacterial cell take to Replicate ?
ReplyDeleteBacteria don’t have a fixed lifespan because they don’t grow old. When bacteria reproduce, they split into two equal halves, and neither can be regarded as the parent or the child. You could say that so long as a single one of its descendants survives, the original bacterium does too.Bacteria divide somewhere between once every 12 minutes and once every 24 hours So the average lifespan of a bacterium is around 12 hours or so. While the division time or the time between the end of replication and completion of division (D period), is the time that elapses between completion of a round of DNA replication and completion of cell division. This is about 20 min. Hence the time for the replication cycle the period required for replication or C period plus D period is essentially constant in bacterial cultures with doubling times shorter than 60 min.
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DeleteBacteria life span varies by type; some has very short life span (minutes to hours) and some has up to years (in inanimate surface lives may be up to hundreds years).Bacteria divide somewhere between once every 12 minutes and once every 24 hours. So the average lifespan of a bacterium is around 12 hours or so.The single chromosome of a bacterium is a loop of double-stranded DNA. The number of bases can vary from one species to another. The well-known bacteria E. coli has 4.7 million base pairs that take about 40 minutes to replicate, implying a speed of over 1,000 bases per second.
DeleteBacteria don't have a fixed lifespan because they don't grow old . When bacteria reproduce , they split into two equal halves , and neither can be regarded as the parent or the child . You could say that so long as a single one of its descendants survives , the original bacterium does too . Individual bacteria can also turn themselves into spores with a tough coat to protect themselves from dry conditions . Bacterial spores have been successfully revived from 250 - million - year - old salt crystals found in New Mexico in 2000. But if we assume that the global bacteria population is stable, then it follows that one bacterium must die for each new one that is produced. Bacteria divide somewhere between once every 12 minutes and once every 24 hours. So the average lifespan of a bacterium is around 12 hours or so.
DeleteWhat is Synchronous Growth?
ReplyDeleteSynchronous Culture / Synchronous growth of a bacterial population is that during which all bacterial cells of the population are physiologically identical and in the same stage of cell division cycle at a given time. Synchronous growth helps studying particular stages or the cell division cycle and their interrelations. In most of the bacterial cultures the stages of growth and cell division cycle are completely random and thus it becomes difficult to understand the properties during the course of division cycle using such cultures. To overcome this problem, the microbiologists have developed synchronous culture techniques to find synchronous growth of bacterial population.
DeleteSynchronous growth is the growth of bacteria such that all the bacteria are at the same stage in their growth cycle (e.g exponential phase,stationary phase).Because the same cellular reactions occur simultaneously throughout the bacterial population, synchronous growth permits the detection of events not normally detectable in a single cell or in a population consisting of bacteria in various stages of growth. In a normal batch culture of fluid, or on an agar plate, bacteria in the population exhibit a range of sizes, ages, and growth rates. In contrast, the bacteria in a synchronized culture are virtually identical in terms of these parameters and synchronized growth is imposed in laboratory. The population of bacteria can be filtered to obtain bacteria of a certain size range. Usually, the filter that is used has very small holes. All but the smallest bacteria in a population are excluded from passing through the filter. Because the smallest bacteria are frequently the youngest bacteria, the filtering method selects for a population comprised of bacteria that usually have just completed a division event. When the bacteria are suspended in fresh growth medium the population will subsequently grow and then divide at the same rate.Bacteria of the same size can also be recovered using special techniques of centrifugation, where the bacteria in the fluid that is spinning around in a centrifuge are separated on the basis of their different densities. The smallest bacteria will have the lowest density and so will move furthest down the centrifuge tube.Their another method of obtaining a synchronous bacterial population involves the manipulation of some environmental factor that the bacteria depend on growth.
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DeleteCell synchronization is a process by which cells in a culture at different stages of the cell cycle are brought to the same phase. Cell synchrony is a vital process in the study of cells progressing through the cell cycle as it allows population-wide data to be collected rather than relying solely on single-cell experiments.Synchronous growth is the growth of bacteria such that all the bacteria are at the same stage in their growth cycle (e.g., exponential phase, stationary phase). Because the same cellular reactions occur simultaneously throughout the bacterial population, synchronous growth permits the detection of events not normally detectable in a single cell or in a population consisting of bacteria in various stages of growth.The types of synchronization are broadly categorized into two groups; physical fractionization and chemical blockade.
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DeleteIn a clear manner Synchronous means where the growth of the bacteria is at the same stage; for example all the bacteria will be in the exponential phase. synchronous growth is usually imposed in laboratory. a synchronous condition is maintained by either manipulating environmental conditions like changing the temperature in intervals or by adding the more nutrients.
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DeleteSynochronous growth is the growth in which all the organismas are in the same stage in their growth cycle. All cells in the culture will divide at the same time,grow for a generation time. Synochronous growth provides the entire cell crop in the same stage of the growth.
DeleteSynchronous culture can define as the growth process of the microbial population, where the individual cells show synchrony with the other cells in the culture medium by growing at the same growth phase for the given generation time.The main characteristic of synchronous growth is that all the microbial cells are physiologically identical by growing at the same division cycle at the same time. Therefore, we can say that the entire microbial population remains uniform concerning cell growth and division.
Deletewhat do think about shift up and shift down in bacterial growth?
ReplyDeleteIn shift-up, a culture is transferred from a nutritionally poor medium to a richer one; and shift-down, where a culture is transferred from a rich medium to a poor one. In a shift-up experiment, there is a lag while the cells first construct new ribosomes to enhance their capacity for protein synthesis. In a shift-down experiment, there is a lag in growth because cells need time to make the enzymes required for the biosynthesis of unavailable nutrients.
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DeleteIn shift-up, a culture is transferred from a nutritionally
Deletepoor medium to a richer one and shift-down, where a culture is transferred from a rich medium to a poor one.
In Shift down process, a nutritional culture is transfered from high medium to low medium. In Shift up process, a nutritional culture is transformed from low medium to high medium content.
ReplyDeleteWhat does Quorum sensing means?
ReplyDeleteQuorum sensing is a process of cell-cell communication that allows bacteria to share information about cell density and adjust gene expression accordingly.
DeleteQuorum sensing (QS) is a process of cell–cell communication that allows bacteria to share information about cell density and adjust gene expression accordingly. This process enables bacteria to express energetically expensive processes as a collective only when the impact of those processes on the environment or on a host will be maximized. Among the many traits controlled by quorum sensing is the expression of virulence factors by pathogenic bacteria. It can also be defined as ,"a bacterial cell–cell communication process that involves the production, detection, and response to extracellular signaling molecules called autoinducers (AIs)".
DeleteGram-positive and Gram-negative bacteria use different types of QS systems.
It means the number of members of a group required to be present to carry out an activity legally. In this process bacteria communicate via secreted signaling molecular called “autoinducers” which contribute to the regulation of the expression of particular genes. It occurs within a single bacterial species as well as between diverse species. In some local insects use quorum sensing to determine where to nest. Quorum sensing has two type of bacteria. Gram positive bacteria and Gram negative bacteria.
DeleteGram positive bacteria. Eg:- Bacillus subtulis and Streptococcus pneumonia use QS to develop competence.
Gram negative bacteria. Eg:- QS in Vibrio fischeri- Bioluminescence is define as the emission of visible light from living organism.
Quorum sensing is a process of cell–cell communication that allows bacteria to share information about cell density and adjust gene expression accordingly. Bacterial communication relies on versatile chemical signaling molecules called autoinducers, which regulate bacterial gene expression in a process known as quorum sensing. Like languages between humans, these signals vary between species. Some bacterial species can interpret many different signals, while others respond to a select few. Quorum sensing allows individual bacteria within colonies to coordinate and carry out colony-wide functions such as: sporulation, bioluminescence, virulence, conjugation, competence and biofilm formation.
DeleteQuorum sensing is a system of stimulus and response correlated to population density. Many species of bacteria use quorum sensing to coordinate gene expression according to the density of their local population. In similar fashion, some social insects use quorum sensing to determine where to nest. In addition to its function in biological systems, quorum sensing has several useful applications for computing and robotics.
DeleteQuorum sensing can function as a decision-making process in any decentralized system, as long as individual components have: (a) a means of assessing the number of other components they interact with and (b) a standard response once a threshold number of components is detected.
Some of the best-known examples of quorum sensing come from studies of bacteria. Bacteria use quorum sensing to coordinate certain behaviors based on the local density of the bacterial population. Quorum sensing allows individual bacteria within colonies to coordinate and carry out colony-wide functions such as: sporulation, bioluminescence, virulence, biofilm formation. Quorum sensing can occur within a single bacterial species as well as between diverse species, and can regulate a host of different processes, in essence, serving as a simple communication network. A variety of different molecules can be used as signals. Common classes of signaling molecules are oligopeptides in Gram-positive bacteria, N-Acyl Homoserine Lactones (AHL) in Gram-negative bacteria, and a family of autoinducers known as autoinducer-2 (AI-2) in both Gram-negative and Gram-positive bacteria.
Quorum sensing is regulation of gene expression in response to changes in cell-population density. The signal molecules which is secreted by bacteria, known as "autoinducers". Gram-negative bacteria use acylated homoserine lactones as autoinducers, and Gram-positive bacteria use processed oligo-peptides to communicate. Quorum sensing process also help in symbiosis, virulence, competence, conjugation, antibiotic production, motility, sporulation, and biofilm formation.
DeleteWhich are the methods for measuring the microbial growth?
ReplyDeleteMicrobial growth can be measured by direct and indirect methods of measurement. Direct methods of measurement includes Plate count(spread plate, pour plate), by Filtration, Most Probable Number(MPN), Direct microscopic count. while indirect methods of measurement includes by Turbidity, Metabolic activity and by obtaining dry weight by centrifugation
DeleteThere are mainly 2 methods for measuring microbial growth : 1. direct method 2. Indirect method .
DeleteDIRECT METHOD includes most probable number (MPN), Standard Plate count (SPC), Filteration , spread plate ,pour plate .
INDIRECT METHOD includes cell mass, cell number , turbidity , dry weight (Centrifugation).
To measurement of Microbial Growth Different method of counting microbial growth :
Delete1.Dryell mass
2. Wet Cell Mass
3.Absorbance
4.Cell Count ( Manual )
5.Cell Count ( Computerised ) / Coulter Counter
6.Viable Cell Count
Microbial growth can be measured by direct and indirect methods of measurement. Direct Method includes most probable number (MPN), Standard Plate count (SPC), Filteration , spread plate ,pour plate .
DeleteIndirect Method includes cell mass, cell number , turbidity , dry weight (Centrifugation).
There are different methods of counting microbial growth. These are based on different parameters of cells such as dry-weight and wet-weight measurement, absorbance ( by using a spectrophotometer), cell plate, density, turbidity, viable count (by stranderd plate count), cell count by Coulter counter, cell count by petroff hausser counting chamber.
DeleteWhat is Biofilm in Microbial Growth ?
ReplyDeleteMicroorganisms attach to surfaces and develop biofilms. Biofilm-associated cells can be differentiated from their suspended counterparts by generation of an extracellular polymeric substance (EPS) matrix, reduced growth rates, and the up- and down- regulation of specific genes. Attachment is a complex process regulated by diverse characteristics of the growth medium, substratum, and cell surface.
DeleteA biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular polymeric substances (EPSs).The cells within the biofilm produce the EPS components, which are typically a polymeric conglomeration of extracellular polysaccharides, proteins, lipids and DNA.Because they have three-dimensional structure and represent a community lifestyle for microorganisms, they have been metaphorically described as "cities for microbes".Microorganisms that form biofilms include bacteria, fungi and protists.
DeleteOne common example of a biofilm dental plaque, a slimy buildup of bacteria that forms on the surfaces of teeth. Pond scum is another example. Biofilms have been found growing on minerals and metals. They have been found underwater, underground and above the ground. They can grow on plant tissues and animal tissues, and on implanted medical devices such as catheters and pacemakers.
biofilm is compromising of microorganisms attached to a living or inert surface in an aqueous environment and surrounded in a matrix of extracellular polymeric substance.
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DeleteBiofilm is a mode of microbial growth where dynamic communities of interacting sessile cells are irreversibly attached to solid substratum, as well as each other,and are embedded in a self made matrix of extracellular polymeric substance (EPS)
DeleteBiofilm formation constitutes an alternative lifestyle in which microorganisms adopt a multicellular behavior that facilitates and/or prolongs survival in diverse environmental niches. Biofilms form on biotic and abiotic surfaces both in the environment and in the healthcare setting. In hospital wards, the formation of biofilms on vents and medical equipment enables pathogens to persist as reservoirs that can readily spread to patients. Inside the host, biofilms allow pathogens to subvert innate immune defenses and are thus associated with long-term persistence. Here we provide a general review of the steps leading to biofilm formation on surfaces and within eukaryotic cells, highlighting several medically important pathogens, and discuss recent advances on novel strategies aimed at biofilm prevention and/or dissolution.Biofilm formation enables single-cell organisms to assume a temporary multicellular lifestyle, in which “group behavior” facilitates survival in adverse environments. What was once defined as the formation of a community of microorganisms attached to a surface has come to be recognized as a complex developmental process that is multifaceted and dynamic in nature. The transition from planktonic growth to biofilm occurs in response to environmental changes, and involves multiple regulatory networks, which translate signals to concerted gene expression changes thereby mediating the spatial and temporal reorganization of the bacterial cell.
DeleteBiofilms are a collective of one or more types of microorganisms that can grow on many different surfaces. Micro-organism that form biofilms include bacteria, fungi and protists. one example of a biofilm is dental plaque, a slimy buildup of bacteria that forms on the surface of teeth. They have been found underwater as well as underground. Also on plant and animal tissues and on implanted medical devices such as catheters and pacemakers
ReplyDeleteWhat is the Size of Whatman Filter paper No.4 ? Does the porosity of Whatman Filter paper No from 4 to 1, Will increase or decrease?
ReplyDeleteThe size of Whatman Filter paper No. 4 is
DeleteCircles: 27 mm to 400 mm
Sheets: 38 x 114 mm to 580 x 580 mm
Yes the porosity of Whatman Filter paper will change from no 4 to 1
Whatman Filter paper No.1 has the pore size of 11 μm. This filter paper is widely used for many different fields in agricultural analysis, air pollution monitoring and other similar experiments.
Whatman Filter paper No.2 has the pore size of 8 μm. This filter paper requires more filtration time than 1 filter paper. This filter paper is used for monitoring specific contaminants in the atmosphere and soil testing.
Whatman Filter paper No.3 has the pore size of 6 μm. This filter paper is very suitable for carrying samples after filtration
Whatman Filter paper No.4 has the pore size of 20-25 μm. This filter paper has the largest pore size among all standard qualitative filter papers. It is very useful as rapid filter for cleanup of geological fluids or organic extracts during experiment.
Whatman Filter paper No.4 has the pore size of 20-25 μm.And as the Whatman filter paper no. increases from 1 to 4 porosity of the filter paper also increases.
DeleteWhy do Archaea bacteria lack Peptidoglycan in their Cell wall ?
ReplyDeletearchaea do not have peptidoglycan layer on their cell wall but they do contain pseudopeptidoglycan which is similar to peptidoglycan which contains different sugar in the polysaccharide chain. the other types of archaea may also have the cell wall composed of polysaccharide, glycoproteins or pure proteins. while archaea lack peptidoglycan, a few contain a substance with a similar structure known as pseudomurein. Instead of NAM, it contains N-acetylalosaminuronic acid (NAT) linked to NAG, with peptide interbridges to increase the strength. The bacteria which has the additional S layer in their structure, but here in archaea the S layer is the part of the cell wall and sometimes be the only S layer a pert of the cell wall. In some of the archaeal cell methanochondroitin may also be the part of the cell wall similar to the connective tissue component chondroitin found in vertebrates. so archaea lacks the peptidoglycan layer but it has the other components to fulfill the requirement.
Deletewhy DNA is not damage at high temperature in hyperthermophiles?
ReplyDeleteHyperthermophiles are adopted to Hot Environment by their physiological and Nutritional requirements. As a consequence,cell components like DNA , protiens , nucleic acid and membrane are stable and even function best at Temperatures around 100 degree celsius.
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DeleteHyperthermophiles are a subset of extremophiles within the domain Archaea. An optimal temperature for the existence ofStanford researchers show that a protein in a microbe's membrane helps it survive extreme environments. ... Scientists had known that this group of microbes – called archaea – were surrounded by a membrane made of different chemical components than those of bacteria, plants or animals
DeleteGenerally, microorganisms with an optimal growth temperature between 60 and 80 degree Celsius are designated as thermophiles, whereas those growing at temperatures of greater than 80 degree Celsius are referred to as hyperthermophiles, which are found in the three domains of life, archaea, bacteria, and eukarya, but the majority are archaea and bacteria.
DeleteNucleic acids are heat-labile macromolecules. At temperatures typical for hyperthermophiles, they are susceptible to denaturation and hydrolysis. Stable RNAs are protected against denaturation in hyperthermophiles by a high GC content and by nucleotide modifications which stabilize their secondary and tertiary structures.
Methylation of 2’OH can also be involved in the protection of stable RNA against hydrolysis of the phosphodiester bonds.
All hyperthermophiles contain a unique enzyme reverse gyrase, which can modify DNA topology. Reverse gyrase is the only protein that is specific for hyperthermophiles. Although the precise role of reverse gyrase is still unknown, this enzyme is probably essential for life at extremely high temperatures.
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DeleteThis comment has been removed by the author.
DeleteNucleic acids are heat-labile macromolecules. At temperatures typical for hyperthermophiles, they are susceptible to denaturation (unwinding of DNA double helices and RNA hairpins) and chemical degradation (hydrolysis). Stable RNAs areprotected against denaturation in hyperthermophiles by a high GC content and extensive nucleotide modifications which stabilize their secondary and tertiary structures.
DeleteMethylation of 2’OH can also be involved in the protection of stable RNA against hydrolysis of the phosphodiester bonds. In contrast to RNA, intracellular DNA is intrinsically stabilized against global denaturation by the existence of topological links between the two DNA strands, explaining why the genomic DNA of hyperthermophiles is not specifically GC rich. However, DNA is susceptible to depurination and cytosine deamination at high temperature. Furthermore, depurination can induce DNA breakage
and subsequent denaturation.Hyperthermophilic Archaea are highly radioresistant, indicating very efficient DNA repair mechanisms.All hyperthermophiles contain a unique enzyme, reverse gyrase, which can modify DNA topology. Comparative genomic analysis reveals that reverse gyrase is the only protein that is specific for hyperthermophiles. This enzyme is probably essential for life at extremely high temperatures.
Hypo thermophiles is the organism which are adapted to grow at even 85 degree Celsius to 113 degree Celsius. the detailed study of the enzymes which were purified from the hyper thermophiles indicated that it has a few critical amino acid substitutions which increases the protein stability. it includes the formation of ion pairs, increase in the hydrogen bonding and steric hinderance of a chain flexibility. The DNA has only four deoxyribonucleotides. As the G-C base pairing has three bonds while the A-T bonding has 2 bonds. The melting point is higher of GC then the AT. if the concentration of the GC is more in the strand than the AT then the Melting point anyhow increases and is prevented from destroying even at the high temp.
DeleteHow to ensure that the same species of Microbe mentioned in Probiotics label is Actually only present in the Product and other Opportunistic microbes are Absent?
ReplyDeleteUrvi Deria(20mmb006)
Delete1.The assessment of species identity by macroscopically, microscopically and physiologically by observing morphology of the colony, gram staining technique and various biochemical tests.
2.Genetic level tests.
How protein engineering has help in making subtilism widely used in detergents industry?
DeleteBy the use of genotyping and phenotyping techniques we can identify the species of microbe mentioned in probiotics.
Delete1. Conventional phenotypic approaches for the identification of probiotics strain.
DeleteIt involves Analytical Profile Index tests, Microscopic analysis, biochemical tests.
2.Molecular approaches for strain identification
It involves Sequence analysis of the partial or complete 16S ribosomal RNA (rRNA) gene of the strain. Other than these DNA Fingerprinting methods (AFLP, RAPD, etc) can also be used for identification of probiotics strain.
So by performing these technique we can make sure that the same microorganisms are used in the probiotics product or any other.
many stains contain proteins, the manufacturers of laundry detergents include subtilisin in their product. Subtilisin is 274 amino acids long, and one of these, the methionine at position 222, lies right beside the active site of the enzyme. This is the site on the enzyme's surface where the substrate is bound, and where the reaction that is catalyzed by the enzyme takes place. In this instance the substrate is a protein in a stain, and the reaction results in the breaking of a peptide bond in the backbone of the protein. Unfortunately, methionine is an amino acid that is very easily oxidized, and laundry detergents are often used in conjunction with bleach, which is a strong oxidizing agent. When used with bleach, the methionine in subtilisin is oxidized and the enzyme is inactivated, preventing the subtilisin from doing its work of breaking down the proteins present in food stains, blood stains, and the like.
ReplyDeleteTo overcome this problem, genetic engineering techniques were used to isolate the gene for subtilisin, and the small part of the gene that codes for methionine 222 was replaced by chemically synthesized DNA fragments that coded for other amino acids. The experiment was done in such a way that nineteen new subtilisin genes were produced, and every possible amino acid was tried at position 222. Some of the altered genes gave rise to inactive versions of the enzyme, but others resulted in fully functional subtilisin. When these subtilisins were tested for their resistance to oxidation, most were found to be very good (except when cysteine replaced methionine: It too is easily oxidized). So now it is possible to use laundry detergent and bleach at the same time and still remove protein-based stains. This type of gene manipulation, which has been called "protein engineering,"
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DeleteBhakti Thakkar(20mbt053)
DeleteBy altering its various factors like catalytic activity, substrate specificity, pH factor etc.
And Protein engineered variants of subtilisin are used to increase catalytic activity of detergent so the rate of reaction going to be increased.
What is the purpose of yeast in bread making?
ReplyDeleteYeast works as leavening agent means it causes the dough to rise,expand and makes it softer.it also ferments the sugar present in dough and converts into carbon dioxide.
DeleteYeast work by serving one of the leavening agent in the purpose of fermentation ,which is essential in making breads. The purpose of many leavener is to produces the gas that makes bread rise.yeast does this by feeding on the sugars in flour,and expelling carbon dioxide in the process.as the yeast feed on the sugar,it produce carbon dioxide with no place to go but up,the gas slowly fills the balloon . A very similar process happens in bread rises. Carbon dioxide from yeast fills thousands of balloon like bubbles in dough.once the bread has baked,this is what gives a loaf its airy texture.
DeleteTwo types of Yeats are used in bread making: regular acive dry and instant yeast( also known as fast rising, rapid rise,quick rise, and or bread machine yeast .
This two types of dry yeast used interchangeably tha advantage of rapid rise is the rising time is half that of the active dry and it only need one rising.
As bread dough is mixed and kneaded, millions of air bubbles are trapped and dispersed throughout the dough. Meanwhile, the yeast in the dough metabolizes the starches and sugars in the flour, turning them into alcohol and carbon dioxide gas. This gas inflates the network of air bubbles, causing the bread to rise.
DeleteYeast is used for the leavening of bread. Yeast uses the sugars and oxygen in dough to produce more yeast cells and carbon dioxide gas. This is called multiplication. The carbon dioxide makes the dough rise which gives the bread a light and spongy texture. Yeast also works on the gluten network. The by-products of "fermentation", or rising, give bread it's characteristic flavour and aroma. The yeast continues to grow and ferment until the dough reaches around 46°C at which temperature yeast dies.
DeleteYeast is most commonly used in baking bread and bakery products .Yeast is used as leavening agent for Bread. Yeast uses the sugar and oxygen in dough to produce more yeast cells and carbon dioxide gas. The carbon dioxide makes the dough rise which gives the bread light and spongy texture.
Deletewhen we add yeast in our flour it breaks the large starch molecules into sugar and that will produce carbon dioxide and ethyl alcohol which make the air bubbles and due to that bubbles bread dough will grow and become spongy.
Deletewhen the yeast is added to the flour and the water mixture, the yeast breaks the large starch molecules into simpler sugars and during this process, it produces carbon dioxide and ethyl alcohol which make the air bubbles that cause the bread dough to grow. it just not add only air bubbles, but also flavors the dough as it break down the tasteless starch molecules into the simpler sweet sugars. the production of ethyl alcohol also somehow add the flavor to the food. when the fermentation process continues for more than days it somehow adds an acidic element to the bread.
Deletemostly yeast use in bread production because they can form dough and dough is helps in texture of bread.Once the bread has baked, this is what gives the loaf its airy texture.
DeleteYeast-mediated dough fermentation is an important phase in the bread making process. The fermentative performance of yeast cells during fermentation is of critical importance for final bread quality, since yeast cells produce CO2 and other metabolites that have an influence on dough rheology and bread texture, volume, and taste.
REFERENCES:
https://www.researchgate.net/publication/328052441_Yeast_its_types_and_role_in_fermentation_during_bread_making_process-_A_review
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ReplyDeleteWe can ensure that the same species of microbes mentioned on label is actually present in product and not other species through in vitro test of probiotic microbial strains , by their site of action for instance if microbe mentioned on label of probiotic is for intestine it will definitely act on its target and not on other place in body so by this we can ensure mentioned microbe by its site of action.
ReplyDeleteBy gram staining we can analyse.
Which is the first company to introduce enzyme based detergent and what are its failure?
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DeleteIn 1960, Schweizerischer Ferment AG was the first ones to introduce enzyme in detergent industry. The company (takenover in 1967 by Novo) marketed Protease B from Bacillus subtilis in 1958, leads to the first introduction of proteolytic enzymes in a detergent in 1959. In 1960, new enzyme product was named Alcalase (subtilisin) , Novo’s first detergent enzyme produced by fermentation.In 1963, a Dutch firm launched the detergent Bio-tex, which contained Alcalase. Side effect:In 1969, According to one article, some workers at a British detergent factory had developed an allergy after inhaling concentrated enzyme dust , as Consumers can be exposed to Subtilisins via the respiratory route during the task of dispensing detergent products in the washing machine or laundry and According to (HERA project) Human Health Assessment also,The key health concern identified for Subtilisin is respiratory (Type 1) allergy.
DeleteThe first company to introduce Enzyme based detergent was the Schweizerischer Ferment AG. The company marketed Protease B from Bacillus subtilis in 1958.
DeleteThe first company to introduce enzyme based deteregent was the Schweizerischer Ferment AG.
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ReplyDelete
ReplyDeleteProbiotics are a combination of live beneficial bacteria and/or yeasts that naturally live in your body. Bacteria is usually viewed in a negative light as something that makes you sick. However, you have two kinds of bacteria constantly in and on your body — good bacteria and bad bacteria. Probiotics are made up of good bacteria that helps keep your body healthy and working well. This good bacteria helps you in many ways, including fighting off bad bacteria when you have too much of it, helping you feel better.
For a microbe to be called a probiotic, it must have several characteristics. These include being able to:
Be isolated from a human.
Survive in your intestine after ingestion (being eaten).
Have a proven benefit to you.
Be safely consumed.
The use of probiotics is not only limited to intestines but also it can be used in
Gut.
Mouth.
Vagina.
Urinary tract.
Skin.
Lungs.
The main function of probiotics is to maintain the check on bad or pathogenic microorganisms that can enter our body through different routes and if we are feeling healthy by the use of different probiotics then we can say the particular probiotics used are effective probiotics also help in the formation of vitamin and help in the absorption of certain medications
Most common probiotics are
Yogurt.
Buttermilk.
Sourdough bread
Cottage cheese.
Kombucha.
Tempeh.
There are also certain risk regarding the use of probiotics that may include
Developing an infection.
Developing a resistance to antibiotics.
Developing harmful byproducts from the probiotic supplement.
https://my.clevelandclinic.org/health/articles/14598-probiotics
Where did minamata disease come from? What kind of substance responsible for minamata disease?
ReplyDeleteThe minamata disease is a disease of the nervous system. It is caused by methylmercy. Minamata disease was first discovered in the city of minamata, kumamota, japan in 1956. It was caused by the release of methylmercy in the industrial wastewater from a chemical factory owned by the Chisso corporation. Minamata disease occurred in humans who ingested fish and shellfish contaminated by methylmercy.
DeleteMinamata disease sometimes referred to as Chisso-Minamata disease is a neurological disease caused by severe mercury poisoning. Minamata disease was first discovered in the city of Minamata, Kumamoto Prefecture, Japan, in 1956. It was caused by the release of methylmercury in the industrial wastewater from a chemical factory owned by the Chisso Corporation, which continued from 1932 to 1968.It has also been suggested that some of the mercury sulfate in the wastewater was also metabolized to methylmercury by bacteria in the sediment.This highly toxic chemical bioaccumulated and biomagnified in shellfish and fish in Minamata Bay and the Shiranui Sea, which, when eaten by the local population, resulted in mercury poisoning.
DeleteMinamata disease also called as Chisso Minamata disease is a neurological disease which was burst due to the poisoning of mercury. it was first discovered in Minamata City in Kumamoto prefecture japan in 1956. it was bursted due to the release of methylmercury in the industrial waste water from the chemical factory. This chemical got accumulated in the marine fishes which were then eaten by the locals resulted in the mercury poisoning. symptoms include ataxia, numbness in the hands and in the feet, general muscle pain or weakness, narrowing in the field of the vision and damage in the hearing and in the voice box too which made the harsh sound.it was also observed that the disease was also affecting the fetus in the womb which was resulting into a non healthy child in future. the cats were also infected with this disease and were called to be known as "DANCING CAT FEVER".
DeleteMinamata disease in Japan is the most famous case of methylmercury food poisoning. The first patient was officially notified to the local Public Health Center in May 1, 1956. The source and transmission mode is contaminated fish and shellfish. The etiologic agent is methylmercury, a by-product of acetaldehyde production, which was discharged from the Chisso factory from 1932 until 1968. During this period, the discharge was not stopped, and no effective measures or investigations were undertaken. The target organ of methylmercury is the central nervous system. The affected patients manifest neurological signs, including paresthesia, ataxia, dysarthria, constriction of the visual field, and/or hearing difficulties. These neurological signs were observed even among residents with hair mercury content below 50 μg g−1. The affected residents manifest psychiatric symptoms (e.g., impairment of intelligence and mood and behavioral dysfunction) as well. It is also reported that the prevalence of hypertension was elevated in the affected areas. A particularly distressing aspect of the disease is that methylmercury can be transferred to fetuses. Severely affected children born with congenital Minamata disease are mental retarded and have disturbed coordination, deformities of the limbs, poor reflexes, poor nutrition and growth, and, in some cases, show other effects. Up to March 2011, 2271 patients were officially recognized as having Minamata disease, but it is estimated that the number of patients in the affected areas who exhibit neurological signs of methylmercury poisoning is in the several tens of thousands.
DeleteREFERENCE: https://doi.org/10.1016/B978-0-12-386454-3.00038-5
probiotic or Antidepressants, which will have a more positive effect on depressed or anxiety patient ?
ReplyDeleteBoth have their own pros and cons. if we are considering that the patient is in the initial stage of the depression the probiotic will affect and will have more positive response in terms of the side effects of the medication while if the patient is already suffering from years probiotic will not anyhow give a very rapid boost to the treatment while the antidepressants may work far better than probiotic. probiotics also seemed to work best when used with the combination of other treatments like medication and psychotherapy.
DeleteAny citation can you provide that can prove your view ?
DeleteWe can not say that probiotics is more effective than Antidepressants or Antidepressants is more effective than probiotics. Probiotics use in primary stage of depression but they don’t replace therapy, medication, or other depression treatments. gut-brain axis (GBA) link with central nervous system and it can affect appetite, mood, or sleep habits. But in 2015 some studies suggest that GBA may be the missing link in our understanding of depression and its causes so, More research is underway on this topic in neuroscience. But probiotics not cause other side effect. Bifidobacterium longum NCC3001 use in study and scientists concluded that they may improve quality of life and reduce symptoms of depression in people with irritable bowel syndrome. Several authors suggest microorganisms as a new group of drugs named “psychomicrobiotics”. So we can say that both are effective.
DeleteREFERENCES:
1 )Evrensel, A., & Ceylan, M. E. (2015). The Gunt-Brai Axis: The Missing Link in Depression. Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology, 13(3), 239–244. https://doi.org/10.9758/cpn.2015.13.3.239
doi: 10.9758/cpn.2015.13.3.239
2) https://www.healthline.com/health/probiotics-depression
Thank you so much for your input
DeleteHow do baceteriocin and antibiotics vary in terms of their mode of action?
ReplyDeleteBacteriocins are produced by the bacteria as a defensive mechanisms against the other bacterial strains of the same species, whereas the activity of antibiotics is broad spectrum.
DeleteAntibiotics harvested from a given bacterial strain can both act against the same species strains as well as on other species too
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DeleteBacteriocins are produced on the surface of ribosomes in microbial cells , Bacteriocins producers are insusceptible to the bactericidal agents.
DeleteAntibiotics are primarily secondary metabolites of the cell. Antibiotics inhibits the cell wall synthesis, inhibition of ribosome function, nucleic acid synthesis.
Bacteriocins are proteinaceous toxins produced by bacteria to kill similar or closely related species, i.e. intraspecies competition is observed here. They have narrow spectrum activity.
DeleteWhereas, Antibiotics kill a broad range of organisms i.e. they can kill same species as well as different species. They have broad spectrum activity.
Bacteriocins are ribosomally-synthesized bacterial antimicrobial peptides (AMPs). It kills food spoilage/pathogenic bacteria from both Gram-positive and Gram-negative group. It forms pores in bacterial cell-membrane, resulting in dissipation of proton-motive force leading to cell death.
DeleteAntibacterial action generally falls within one of four mechanisms, three of which involve the inhibition or regulation of enzymes involved in cell wall biosynthesis, nucleic acid metabolism and repair, or protein synthesis, respectively. The fourth mechanism involves the disruption of membrane structure. Many of these cellular functions targeted by antibiotics are most active in multiplying cells.Effective against prokaryotic bacterial cells and eukaryotic mammalian cells.
Bacteriocins restrict their activity to the strains of species related to the producing species and particularly to strain of the same species while the activity of the antibiotics is in the broad spectrum. they inhibit the cell wall synthesis, cell membrane function, protein synthesis etc while bacteriocins also adapts to the same inhibition but works in the respective surrounding of the species while the antibiotics work in a far range.
DeleteHow the growth in microbiology differs growth in macrobiology?
ReplyDeleteIn case of animal or plants the growth is about increase in size but in microorganisms its about increase in number of organisms so in zoology and botanical specimen it is about growth of the cell and growth of organisms,since in microbiology the individual is so small that is bacteria we need to see in population level otherwise it become difficult but you can still count microorganism in TDs form.
DeleteMicrobiology is the study of all living organisms that are too small to be visible with the naked eye. This includes bacteria, archaea, viruses, fungi, prions, protozoa and algae, collectively known as 'microbes'. As the size of microraganism is so small so the growth here is measured by the increase in cell number.
DeleteMacrobiology is the branch of biology that studies large living organisms (termed Macro organisms) that can be seen by the naked eye. So here the growth is measured in terms of increase in cell mass or size.
Microbiology is the study of all living organisms which are so small that cannot be seen with the naked eye , It is the branch of science that deals with microorganisms.
DeleteMacrobiology is the branch of biology that studies large living organisms that can be seen with naked eye.
Macrobiology is the opposite of Microbiology.
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ReplyDeleteMacrobiology is the branch of biology that studies large living organisms (termed Macro organisms) that can be seen by the naked eye,growth for multicelluar organisms is typically measured in terms of the increase in size of a single organism whereas Microbiology is the study of all living organisms that are too small to be visible with the naked eye. microbial growth is measured by the increase in population, either by measuring the increase in cell number or the increase in overall mass.
ReplyDeletewhy does the ultraviolet radiation have limited application in food preservation?
ReplyDeleteUV radiations are lethal to most of the microorganisms and hence applied to inactivate the microorganisms so that they do not reproduce and multiply. The use of UV is not very frequent, but it has a great potential to be used instead of any other processing techniques to preserve the solid and liquid foods. The reason to its limited application is due to its low penetration power. Since, it has low penetration power it will be useful only for surface application rather than complete preservation and sterilization.
DeleteThe ultraviolet radiation have limited application because ultraviolet light limits its use to surface application .
ReplyDeleteThe radiation is not very penetrating so the organisms to be killed must be directly exposed to the Ray's.
UV light is effective for microorganisms not for chemicals.
UV light can damage human eye,and prolonged exposed can cause burns and skin cancer so its affect workers who works in food industry
UV light does not delete but only breaks.
Generally, foods are thermally processed to destroy the vegetative microorganisms for food preservation. However, only thermal treatment triggers many unwanted biochemical reactions, which leads to undesirable sensorial and nutritional effects. Therefore, a number of nontraditional preservation techniques are being developed to satisfy consumer demand with regard to nutritional and sensory aspects of foods. Ensuring food safety and at the same time meeting such demands for retention of nutrition and quality attributes has resulted in increased interest in emerging preservation techniques. The radiation techniques like UV, Gamma have been widely studied and, like most food processing techniques, can induce some changes that are able to modify the chemical and nutritional characteristics on foods. These changes are dependent on some factors such as the radiation dose, the constitution of the irradiated food, the type of packaging, and how it was processed, besides the variables of the process as temperature and oxygen saturation on the atmospheric. BUT there are some limitations. According to the research, UV-light treatment has been shown to be able to significantly alter vitamin content in milk samples when compared to the traditional pasteurizing process. However, these methods are considered safe and effective, according to several agencies such as the Food and Drug Administration (FDA).
ReplyDeleteWhich of the following factor that affects the storage storage stability of food?
ReplyDeleteThis comment has been removed by the author.
DeleteTemperature that affects the storage stability of food
Deletetemperature at which food is stored is very critical to shelf life. United States Department of Agriculture, USDA, states that for every 10.8 degrees in temperature rise you decrease the shelf life of stored food by half. The best range for food storage is a constant temperature between 40-60 degrees.
The Factors that affect Food Storage are -
Delete1. Moisture - For long term storage foods should have 10% or less moisture content. It is recommended to remove moisture when storing foods.
2. Oxygen - Foods store best when oxygen free. Removing oxygen will prevent oxidation of compounds in foods.
3. Temperature - The temperature at which food is stored is very critical to shell life. Avoid freezing temperatures.
4. Light - light a form of energy that can degrade value of foods . Store food in dark areas.
5. Container - Store foods in food grade plastic, metal, or glass containers indicating that the container does not contain chemicals that could be transferred to food and harmful to your health.
1. Temperature plays a very critical role in the storage stability. it is stated that 10.8 degree rise in temp can decrease the shelf life by half. the food ca be best stored at 40 to 60 degrees Celsius.
Delete2. moisture - while storing for the long term it is very necessary to remove the moisture.
3. oxygen - food is stored for long term at a very best when the oxygen is removed as the removal of the oxygen prevents the oxidation of compounds in the foods.
4. light - light can degrade the food so it is best to store food in dark rooms.
5. container - always store the food in a good plastic quality or a metal/glass container. it should be ensured that the low quality plastic and the metals can transfer the chemicals into food which anyhow lowers the taste of the product and can be harmful to your health. the best storage container for food is air tight containers.
There are four factors that affect food storage, which are temperature, moisture, atmosphere and container choice.
ReplyDelete1} Temperature greatly affects food storage life.
For every 10 degrees-C, shelf life will halve (hotter) or double (cooler).
2} The moisture content of the food itself (some exceptions including ‘canned’ or ‘home canned’, or other sealed processing).
Moisture in the storage environment.
For long-term storage of grains, dehydrated foods, and other ‘dry foods’, drier is better.
For example, grains should maintain a moisture content of 10% or less.
3}Earth’s atmosphere contains about 78% nitrogen and 21% oxygen. Oxygen oxidizes many of the compounds in food and reduces it’s shelf life over time.
Bacteria, one of several agents which make food go rancid also needs oxygen to grow.
For maximum shelf life, foods should be stored in an oxygen free environment.
4}Common sealing methods/containers include vacuum sealed bags (Food Saver), sealed Mylar bags, commercially sealed cans or jars, home-canned, sealed food storage buckets/pails.
Factors that affect food storage:
ReplyDeleteTemperature: The temperature at which food is stored is very critical to shelf life. The best range for food storage is a constant temperature between 40-60 degrees. Avoid freezing temperatures.
Moisture: It is recommended to remove moisture when storing foods. For long-term storage, foods should have a 10 percdent or less moisture content.
Oxygen: Foods store best when oxygen free.
Light: Light transfers energy to the food products causing them to degrade in nutrition and appearance. Store food in dark areas.
Container: Store foods in food-grade plastic, metal or glass containers indicating that the container does not contain chemicals that could be transferred to food and be harmful to your health.
Some environmental factors which affect the food storage stability like
ReplyDelete1. Temperature and also sometimes in certain conditions packaging material also affects the temperature of food.
2.gas atmosphere / oxygen
Basically atmospheric oxygen has harmful effects on nutritive quality of food and because of that sometimes lipid oxidation cause loss of vitamins.
3.light
Many deteriorative changes in food are started by light and the intensity of light and length of exposure are main factors in the production of discoloration and flavour defects in food.
Also some chemical reaction affects the food storage like aldehyde and ketone which are more unstable from autooxidation, sometimes cause painty,fatty,candle like flavour in food.
This comment has been removed by the author.
ReplyDeleteTemperature: The temperature at which food is stored is very critical to shelf life. United States Department of Agriculture, USDA, states that for every 10.8 degrees in temperature rise you decrease the shelf life of stored food by half. The best range for food storage is a constant temperature between 40-60 degrees. Avoid freezing temperatures.
ReplyDeleteMoisture: It is recommended to remove moisture when storing foods. For long term storage foods should have a 10% or less moisture content.
Oxygen: Foods store best when oxygen free. Removing oxygen will prevent oxidation of compounds in foods. Ways to remove oxygen:
Displacing oxygen – Purge air from product with an inert gas (nitrogen). Dry ice is often used giving off carbon dioxide gas which displaces oxygen.
Oxygen absorber – Air contains about 78% nitrogen and 21% oxygen, leaving about 1% for the other gasses. If the oxygen is absorbed, what remains is 99% pure nitrogen in a partial vacuum.
Light: Light, a form of energy that can degrade the food value of foods. Store food in dark areas.
Shelf date is the “best if used by” date meaning that you are getting most of the original taste and nutrition. The “life sustaining shelf life” date means the length of time that food is still edible.
What is the difference between a habitat and niche?
ReplyDeleteHabitat and Niche are closely related terms having a thin line of Difference.
DeleteNiche is the specific role of any particular species plays in an ecosystem.
whereas Habitat is the physical place where any particular species lives and adapts to the environmental conditions. Eg - mountains or Grassland.
A habitat is a natural environment where a particular organism lives and utilizes the resources of that place for their survival, food, protection, shelter and mating. whereas niche is a functional role and position of a species in its environment that describes how the species responds to the resources and competitors or predators
DeleteA habitat is the general place where an organism lives and a niche is the range of physical and biological conditions in which a species lives and the way the species obtain what it needs to survive and reproduce.
Deletehabitat :Habitat can be defined as the natural environment of an organism, the type of place in which it is natural for it to live and grow.
DeleteNiche :It encompasses both the physical and environmental conditions it requires and the interactions it has with other species.
Habitat is a natural place where an organism gets all requirements i.e. all necessary components biotic and abiotic factors which unit to form a suitable and survivable place. while niche is a particular place within habitat where an organism performs all its activity and interaction with other organism.
DeleteHabitat is not specific to species but Niche is specific to a particular species
Habitat is larger in size than the niche.
reference: https://microbenotes.com/habitat-vs-niche/
A habitat is a natural environment where a particular organism lives and utilizes the resources of that place for its survival, food, shelter, protection, and mating. The term habitat has been derived from the Latin word, ‘habitāre’ which means ‘to inhabit’. The habitat of an organism is characterized by its physical and biological characteristics. The physical factors include the nature of the soil, availability of land, sunlight, temperature, and climatic conditions. The biological factors include the availability of food and the absence or presence of predators.
DeleteNiche is the functional role and position of a species in its environment that describes how the species responds to the distribution of resources and competitors or predators. Like habitat, the niche is also determined by both the biotic and abiotic factors of the particular environment. However, a niche represents the interactions of a population with these factors and its effect on the environment and other organisms within the environment. For example, a population in an environment utilizes the resources and breeds to produce more organisms which then increases the resources for the predators.
Reference: https://microbenotes.com/habitat-vs-niche/
The role a species plays in the ecosystem is called its niche. A habitat is the physical environment in which a species lives.
DeleteA habitat is about a area where different species lives while a niche is an ideology that how an organisms lives. Habitat is a physical place while niche is activity which is performed by organisms.
ReplyDeleteHabitat is the general place where an organism lives and a niche is the functional role and position of a species in its environment that describes how species responds to the distrubution of resources and competitors.
ReplyDeleteA habitat defines the interaction of organisms with the other factors, which can be living or non-living, while niche describes how that specific organism is linked with its physical and biological environment. Habitat is the part of the ecosystem, while niche plays an important role in the formation of an ecosystem.
ReplyDeleteHabitat is a physical address of a particular organism or species,a place where organisms live,while Niche is the functional address and it includes habitat also,it shows where a particular species live and what it is doing there (it shows abiotic and biotic association with the environment.It shows role of an organism in its ecosystem).
ReplyDeleteWhat are the Salient Features of Algae ?
ReplyDeleteAlgae are autotrophic organisms and they have chlorophyll. They are O2 producing photosynthetic organisms that have evolved in and have exploited an aquatic environment. The study of Algae is known as Algology or phycology.
DeleteIn Algae the plant body shows no differentiation into root, stem or leaf or true tissues. Such a plant body is called thallus. They do not have vascular tissues. The sex organs of this group of kingdom plantae are not surrounded by a layer of sterile cells.
1. Algae include a group of about of 30,000 species which are generally aquatic (both freshwater & marine).
Delete2. Their size varies from microscopic forms to the filamentous forms.
3. All the members of algae are Chlorophyllus, non-vascular thallophytes.
4. They contain chlorophyll a, carotenes and xanthophylls. Additional pigments occur in specific groups.
5 Vegetative and asexual modes of reproduction are very common. Asexual spores are of two types: mitospores and meiospores. They are easily dispersed in aquatic habitat, actively, if motile and passively by water currents, if non-motile.
6.Sex organs are non jacketed.
. Different types of life cycle occur, viz., Haplontic (haploid phase dominant), Diplontic (diploid phase dominant) and Haplodiplontic (both haploid and diploid phase equally dominant).
These are simple living organisms that have chlorophyll. They are the simplest forms of producers in a food chain. They can be single-celled or multicellular. Known to be largely aquatic, algae have a thalloid structure, without much differentiation. You can find algae in a variety of habitats such as freshwater, marine, moist stones, wood, and even soil. A mutual association is found in between fungi and algae, leading to an entirely new organism called the lichens.
DeleteThis comment has been removed by the author.
Delete1. They are mostly chlorophyll containing autotrophic thalloid plants.
Delete2. They occurs in a variety of habitats, but majority of them are aquatic.
3. They store food material in the form of starch.
4. They have mostly unicellular sex organs without a jacket of sterile cells around them. Jackets cells,if presents have different initials. There is a progressive complexity in reproduction.
5. Embryo is not formed after gametic union.
6. They shown distinct alternation of generation.
1.At the beginning of the history of life, algae changed the atmosphere of the planet by producing oxygen, thus opening the way for the evolution of eukaryotic organisms so we can say that algae is also responsible for evolution.
Delete2. 3.5 billion years ago prokaryotic life began on the planet in the absence of oxygen. The cyanobacteria (blue–green algae) arose and began releasing oxygen into the atmosphere as the waste product of chlorophyll a-mediated photosynthesis.
3.the production of oxygen by algae (about 50% of all oxygen production) is another reason to say "our lives depend on algae".
4.algae are the main producers on which aquatic ecosystems depend and they maintain food chain
5.They are one of the main sources of sustainable biofuel production and CO2 consumption.Finally, the algae that gives us the air, the food and the fuel
6.algae are also a source of active pharmaceutical compounds which may be used against drug resistant strains of bacteria, viruses like herpes simplex and AIDS and cancers.
7.The total biomass of the world's algae is just one tenth of the biomass of all other plants, the efficiency of algae is impressive.
8.Red algae are the source agar and carrageenans and they use in hundreds of products, including ice cream, beer, soy milk and pet food, among others.
9.Porphya red seaweed is also harvested as Nori and is dark purple - reddish wrap used in sushi around the world.
10.Brown algae are often major components of the rocky intertidal zone and therefore are exposed to low tide and must withstand both desiccation and, in many cases, full force of major wave action when the tides come in.
reference: Chapman, R. L. (2013). Algae: the world’s most important “plants”—an introduction. Mitigation and Adaptation Strategies for Global Change, 18(1), 5-12
DOI 10.1007/s11027-010-9255-9
1. The algae traditionally are viewed as photosynthetic eukaryotic microorganisms that do not exhibit tissue differentiation and do not develop from embryos supported by maternal tissue.
Delete2. They can be unicellular or multicellular. Multicellular algae may be filamentous. Unicellular algae may be spherical,rod shaped,club shaped.
3. Algae store various products within their cells, often in vacuoles or in association with the pyrenoid regions of chloroplasts.
4. Algae reproduce asexually or sexually. Asexual reproduction occurs by fragmentation, spore formation and binary fission. Sexual reproduction involves fusion of gametes to form zygote.
5. The algae is an important part of ecosystem. It serves as producers. It can used as food supplements. Some algal species produce agar agar.
Salient features:
Delete1. Algae include a group of about of 30,000 species which are generally aquatic (both freshwater & marine).
2. Their size varies from microscopic forms to the filamentous forms.
3. All the members of algae are Chlorophyllus, non-vascular thallophytes.
4. They contain chlorophyll a, carotenes and xanthophylls. Additional pigments occur in specific groups.
5. Mucilage protects algal thallus from desiccation and from epiphytic growth.
6. Vascular & mechanical tissues absent.
7. Vegetative and asexual modes of reproduction are very common. Asexual spores are of two types: mitospores and meiospores. They are easily dispersed in aquatic habitat, actively, if motile and passively by water currents, if non-motile.
8. Sex organs are non jacketed.
9. Sexual reproduction usually occurs towards the end of growing season.
10. Embryonic stage absent which is a characteristic feature of thallophyta.
11. Sexual reproduction involves isogamy, anisogamy and oogamy in different groups.
12. Different types of life cycle occur, viz., Haplontic (haploid phase dominant), Diplontic (diploid phase dominant) and Haplodiplontic (both haploid and diploid phase equally dominant).
Reference
https://www.biologydiscussion.com/algae/what-are-the-salient-features-of-algae/5549
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ReplyDeleteHow to Grow Thermophilic organisms in lab?
ReplyDeleteSamples are collected from
Deletedifferent sites of hot spring in sterile
vacuum flasks which are able to keep the
temperature constant. The samples were brought in
the laboratory within 2 hours of collection for
processing. Physical and chemical properties of
water samples are first tested and presence of heavy
metals and nutrients are also determined.
For isolation the sample is first initially inoculated under sterile
conditions on both nutrient agar and thermus agar
media. The nutrient agar (NA) is general media
which allows the growth of a wide range of
microorganism whereas thermus agar (TA) medium
is specific for growth of thermophilic bacteria only.
After culturing, the plates are incubated at
different temperatures 40oC, 50oC, 60oC 70oC, 80oC
and 90oC for 48-72 hrs.
Ref. - Research Article- Thermophiles: Isolation, Characterization and Screening for
Enzymatic Activity
Jean Bosco Nshimiyimana1,2, Sujan Khadka*2,3, Esther Muhindo Mwizerwa1
, Nathan Akimana1
,
Sanjib Adhikari3
, Antoine Nsabimana1
We can grow the bacteria at temperatures as high as 65-70 C to count, however we can use Thermus agar which is resistant to higher temperatures.
DeleteIt depends on which kind of thermophilic bacteria we have. If we have Thermus sp, Bacilli or other kind we should use different special Media
thermophilic bacteria are the microbes that mostly inhabit hot springs, live and survive in temp above 80 degree celsius. thermophilic micro0rganisms have gained world wide importance due to their tremendous potential to produce thermostable enzymes that have wide use in industries and pharmaceuticals. the soil sample from the hot spring areas is collected and are cultured in the nutrient agar medium. the tubes are incubated at 50 degree for 12 hours and then the culture of the bacteria is streaked into the another fresh medium and after the growth it is heated in more temp to see the tolerance at higher temp. the thermus agar is used as it can withstand with the temp. after isolating the bacteria with the staining procedure it is studies further whether it is gram positive or gram negative, the shape of the bacteria is also studied.
DeleteHow are barophiles capable of surviving at such high pressure present in deep marine trench?
ReplyDeleteBacteria under high hydrostatic pressure regulate the fluidity of membrane phospholipids to compensate for pressure gradients between the inside of the cell and the environment.
DeleteReference: serc.carleton.edu
Barophiles are defined as organisms which grow optimally or preferentially at pressures greater than atmospheric pressure (0.1 MPa).
DeleteThe lipid compositions of barophilic bacterial strains which contained docosahexaenoic acid (DHA [22:6n-3]) were examined, and the adaptive changes of these compositions were analyzed in response to growth pressure. In the facultatively barophilic strain 16C1, phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) were major components which had the same fatty acid chains. However, in PE, monounsaturated fatty acids such as hexadecenoic acid were major components, and DHA accounted for only 3.7% of the total fatty acids, while in PG, DHA accounted for 29.6% of the total fatty acids. In response to an increase in growth pressure in strain 16C1, the amounts of saturated fatty acids in PE were reduced, and these decreases were mainly balanced by an increase in unsaturated fatty acids, including DHA. In PG, the decrease in saturated fatty acids was mainly balanced by an increase in DHA. Similar adaptive changes in fatty acid composition were observed in response to growth pressure in obligately barophilic strain 2D2. Furthermore, these adaptive changes in response were also observed in response to low temperature in strain 16C1. These results confirm that the general shift from saturated to unsaturated fatty acids including DHA is one of the adaptive changes in response to increases in pressure and suggest that DHA may play a role in maintaining the proper fluidity of membrane lipids under high pressure.
Reference : https://www.ncbi.nlm.nih.gov/pmc/articles/PMC106069/
High pressure and low temperature in deep-sea environments theoretically decrease the fluidity of lipids and possibly depress the functions of biological membranes . Thus, barophiles seem to have some mechanism which allows their lipids to adapt to deep-sea environments.
DeleteRecent research on the physiology and molecular biology of deep-sea barophilic bacteria has identified pressure-regulated operons and shown that microbial growth is influenced by the relationship between temperature and pressure in the deep-sea environment.
A piezophile, also called a barophile, is an organism which thrives at high pressures, such as deep sea bacteria or archaea. They are generally found on ocean floors, where pressure often exceeds 380 atm (38 MPa). Some have been found at the bottom of the Pacific Ocean where the maximum pressure is roughly 117 MPa. The high pressures experienced by these organisms can cause the normally fluid cell membrane to become waxy and relatively impermeable to nutrients. These organisms have adapted in novel ways to become tolerant of these pressures in order to colonize deep sea habitats. One example, xenophyophores, have been found in the deepest ocean trench, 6.6 miles below the surface.
Deletebarophile is an organism which grow at higher pressure than atmospheric pressure. they grow rapidly at low temp and high pressure in deep sea environments which theoretically decrease the fluidity of lipids and the functions are also depressed of the membranes. barophiles have adapted to the mechanism which allows their lipids to adapt to deep see environments. it is been observed that increase in the pressure eventually increases the level of unsaturated fatty acids.
Deleteit is also observed that deep marines bacteria have the PUFA which eventually is not present in the terrestrial bacteria. PUFA such as docosahexaenoic acid DHA and eicosapentaenoic acid EPA are found in the lipid layer of the bacteria. PUFA have the low melting point and they may assist in maintaining the proper fluidity of membrane lipids so that they can adapt to the deep sea environment.
Two strains of obligately barophilic bacteria were isolated from a sample of the world’s deepest sediment, which was obtained by the unmanned deep-sea submersible Kaiko in the Mariana Trench, Challenger Deep, at a depth of 10,898 m. From the results of phylogenetic analysis based on 16S rRNA gene sequences, DNA-DNA relatedness study, and analysis of fatty acid composition, the first strain (DB21MT-2) appears to be most highly similar to Shewanella benthica and close relatives, and the second strain (DB21MT-5) appears to be closely related to the genus Moritella. The optimal pressure conditions for growth of these isolates were 70 MPa for strain DB21MT-2 and 80 MPa for strain DB21MT-5, and no growth was detected at pressures of less than 50 MPa with either strain. This is the first evidence of the existence of an extreme-barophile bacterium of the genus Moritella isolated from the deep-sea environment.
DeleteHigh pressure cause reducing the fluidity in cell membrane by increasing packaging of fatty acyl chains of phospholipid. This causes gel like membrane which interferes in nutrient uptake and cell signaling.
ReplyDeleteBut in barophiles (piezophiles) this is prevented by increasing the proportion of monounsaturated and polyunsaturated fatty acids in their membrane and which can not be packed as tightly as saturated fatty acids.
High hydrostatic pressure (change in conformation of cellular proteins). While pressure is in range it shows that barophiles are not able to denature the proteins and the small conformations changes cause changes or inhibition of protein function or destabilizations of protein structure.
E.g. barophiles shewanella bacteria shows lower concentrations of proline residues whose cyclic side chain distrubs alpha helix and glycine residues having side chains with high conformational flexibility which also destabilize helical protein structure.
And these modification indicates overall decrease in protein flexibility and increase stability in hidh pressure environment.
How a chemostat can be used for the isolation of fastest growing species from a mixed culture?
ReplyDeletechemostat is a bioreactor in which fresh medium is continuously added, while culture liquid containing left over nutrients, metabolic end products and microorganisms are continuously removed at the same rate to keep the culture volume constant ,continuously operated bioreactors where growing cells reach a steady state condition at which specific growth rate, as well as substrate and the product concentrations remain constant. In this way fastest growing bacteria can be isolated as continuously fresh medium is provided,fastest growing bacteria needs constant supply.
DeleteThe growth rate of fastest growing bacteria can be determined by the rate at which new medium is fed into the growth chamber.so useful for isolation.
The chemostate is an experimental apparatus where the chemical environment can be maintain static and fresh medium is added continuously and culture liquid removed by keeping culture and chemical environment constant.
DeleteFastest growing species need more nutrient compare to other species,chemostate provide continuous nutrient so it can be used for isolation of fastest growing species.
the chemostat is a bioreactor to which fresh medium is continuously added, while the culture liquid containing the leftover nutrients, metabolic end products and microorganisms are continuously removed at the same rate to keep the culture volume constant.
Deletefastest growing bacteria's requirement is more as it will need more nutrient and the accumulation of the toxic substance should also removed at the regular interval so it does not interfere in the growth cycle and chemostat is exactly functioning like that providing nutrient and removing the debris of toxic substance.
Chemostats are continuously operated bioreactors where growing cells reach a steady state condition at which specific growth rate, as well as biomass, substrate and the product concentrations remain constant.
DeleteThey are therefore an extremely powerful tool for the precise analysis of cell metabolism and with the miniaturization their role in biological and physiological research, and for the growth model parameters evaluation, got even higher potential.
One of the first continuously operated microbioreactor had six units with a working volume of 16 nL working in parallel on a single chip. One of the main advantages enabling to monitor the programmed behavior of bacterial populations for hundreds of hours was an active approach to preventing biofilm formation. The microchemostat, where mixing was obtained by circulating flow in a microfluidic loop, operated by alternating continuous circulation with dilution and cleaning by means of a lysis buffer. The miniaturized device enabled automated culturing and monitoring of populations of 100 to 104 bacteria with instantaneous single-cell resolution.
Chemostats are an example of continuous cultures wherein the rate at which the sterile media is incoming having at least one essential nutrient in limiting concentrations is equal to the rate of removal of microorganisms along with media. thus final cell density of culture depends on the nutrient in its limiting concentrations. Rate of nutrient exchange is expressed by the dilution rate wherein D= f/V where f=flow rate in (ml/hr) and V=volume of vessel(ml). Population size and generation time are dependent on the dilution rate. In a mixed culture, as dilution rate increases generation time decreases as more nutrients are available thus energy can be conserved both for reproduction as well as metabolism and the growth rate increases thus resulting in the complete depletion of the limiting nutrient. whereas when dilution rate is too high i.e. greater than the maximum growth rate, the microorganisms are washed out before even reproducing. This happens as the competition for the nutrients arises among the microorganisms and the fastidious microorganisms having high generation time than the others is able to utilize the nutrients for both maintenance as well as reproduction thus the progeny of fastidious microorganisms survive. As for example, the dilution rate is 7 minutes-1 and the generation time of fastidious microorganisms is 6 minute-1 then their progeny survives and the rest of the microorganisms are washed out before reproduction.
DeleteIf we want all the cells to be in the same stage of their cell cycle how can we do so. How can we obtain a synchronous culture?
ReplyDeleteA synchronous culture (organisms at same stage)obtained by manipulating environmental conditions such as by changing the temperature or adding fresh nutrients as soon as they enter to stationary phase or by centrifugation or by filtration.
DeleteMost widely used method for obtaining the synchronous culture is the helmstetter-cummings technique.
In which unsynchronized bacterial culture is filtered by cellulose nitrate filter. Tightly bound cells remain on filter while loosely bound cells are washed. The filter is now inverted and fresh medium is adding on it and flow through it.
New bacterial cell which are produced by cell division that are lightly bound with it and washed with effluent.Therefore,in effluent presented all the cell are newly formed and are at the same stage of growth. Thus the effluent which is referred as synchronous culture.
Synchronous growth can be achieved by membrane filteration technique (Helmstetter and cummings).Here, cells are implanted on a membrane filter and the membrane is subjected to reverse flow of liquid medium.By using filter of small pores bacteria of a certain size range are obtained. The smallest bacteria in a population are excluded from passing through the filter. Because the smallest bacteria are frequently the youngest bacteria, the filtering method selects for a population of bacteria that have just completed a division event. so the effluent stream only have bacteria with newborn cell.When the bacteria are suspended in fresh growth medium the population will subsequently grow and then divide at the same rate.
DeleteThere are some other induction method also available like induction methods also used. Temperature shocks, both hot and cold, and combinations of heat and cold have been used to induce synchrony,centrifugation, nutritional techniques such as allowing the growth medium to become depleted with respect to one of the nutrients and then transferring the organisms to fresh complete medium
DeleteExternal conditions can be changed, so as to arrest growth of all cells in the culture, and then changed again to resume growth. The newly growing cells are now all starting to grow at the same stage, and they are synchronized. For example, for photosynthetic cells, light can be eliminated for several hours and then re-introduced. Another method is to eliminate an essential nutrient from the growth medium and later re-introduce it
If we want all the cell to be in the same stage of their cell cycle we can obtain by using synchronous growth techniques.
DeleteThere are three techniques.
1.INDUCTION TECHNIQUES
The most frequently employed methods for inducing synchrony involve temperature cycles (temperature shocks), light cycles, and chemical manipulations. When temperature is used to induce synchrony, the cells are subjected to alternating cold and warm periods.Little cell division occurs during the cold periods, but on entry into the warm periods, cell division commences. For example, cultures of the flagellate protozoan Polytomella agilis can be synchronized by a repetitive temperature cycle of 22 hours at 9°C followed by 2 hours at 25°C.
2.SELECTIVE TECHNIQUE:
synchronous population can be selected by physical separation of cell at the same stage of cell cycle by differential filtration or density centrifugation.
3.HEMSTETTER-CUMMINGS TECHNIQUES:
it is an excellent selective technique, which is based on the fact that certain bacteria stick tightly to cellulose nitrate paper.
The technique involves filtering on unsynchronized culture of bacteria through a membrane filter then inverting the filter, allowing fresh medium to flow through it.
After loosely associated bacteria have been washed from filter, the only bacterial cells in effluent stream of medium are those that arise through division.
Hence, all cell in the effluent are newly formed and are therefore at the same stage of the cell cycle.
synchronous growth is the growth of the bacteria such that all the bacteria are at the same stage in their growth cycle. all cells in the culture will divide at the same time, will grow for a generation time, and all will divide again at the same time. thus the entire population will kept uniform with respect to the growth and division.
DeleteThere are two methods from which the synchronous culture can be obtained.
1. according to the age or size by physical separation of cells.
2. a culture is manipulated by the change in the physical environment or the chemical composition of the medium to obtain a synchronously dividing culture.
1 SELECTION BY AGE AND SIZE
the cells are filtered so the smallest cell pass through the filter. the smallest cells are the young cells and must go through their whole life cycle before dividing. alternatively, the largest cells which are ready to divide may be retained by a filter.
The Helm Stetter-Cummings technique usually is used in which the cells are passed through membrane filter of pore size small enough to trap bacteria in the filter. the filter is then inverted, and fresh nutrient medium is allowed to flow through it. after loosely associated bacteria are washed from the filter, the only bacterial cells in the effluent stream of the medium are those which arise through division.
2. SELECTION BY INDUCTION TECHNIQUE
a synchronous culture is also obtained by the use of shock treatments. these include variation in temp, starvation, exposure to light, drugs and sub lethal doses of radiation. a commonly used technique involves submitting a culture of microorganisms to single or multiple changes in temp. an exponentially growing culture at 37 degree is held for about 30 minutes in 20 degree. the lower temp retards cell division. during the interval of 30 minutes all the cell mature to the point. however, at 20 degree none divide. on sudden return of the culture to 37 degree, all the cells divide synchronously.
DeleteA synchronous or synchronized culture is a microbiological culture or a cell culture that contains cells that are all in the same growth stage.
Synchronous cultures can be obtained in several ways:
External conditions can be changed, so as to arrest growth of all cells in the culture, and then changed again to resume growth. The newly growing cells are now all starting to grow at the same stage, and they are synchronized. For example, for photosynthetic cells, light can be eliminated for several hours and then re-introduced. Another method is to eliminate an essential nutrient from the growth medium and later re-introduce it.
Cells in different growth stages have different physical properties. Cells in a culture can thus be physically separated based on their density or size, for instance. This can be achieved using centrifugation (for density) or filtration (for size).
nowadays we see many advertisements of bulb, ac, and other things have antibacterial property so how can they kill bacteria of surrounding is it harmfull for our skin because bacteria generally found surface of our skin ?
ReplyDeletethe intensified LED blue light excites certain molecules in harmful micro-organisms through photo-activation. Reactive oxygen species are then produced that damage and kill the harmful cells. Till date researchers have found no harmful effects on skin.
DeleteVarious things like bulb, A.C. and also certain metals have antibacterial property. For example - The Syska Bactiglow is a 2-in-1 LED bulb that also works as an antibacterial bulb. It emits Ultraviolet Germicidal Irradiation (UVGI), that uses short wavelengths (safe for human exposure) to effectively kill germs and resist to grow around you. It does not emit any UV/IR radiations but only visible light, which is safe for human exposure and is photobiologically safe. The Syska Bactiglow emits light in the wavelength of
Delete400 to 420 nm which is safe for human exposure. Research scientists have also been working in these and have found no harmful effects to humans.
Can probiotic be the means of drug delivery in future days? what are the possibilities?
ReplyDeleteYes,recent research show that probiotic can be use as a drug delivery.
ReplyDeleteCurrent cancer therapies have limited efficacy because they are
highly toxic to both cancer cells and normal tissue. A growing body of
evidence suggests that LAB(lactic acid bacteria) have chemopreventive effects, even though the magnitude of these effects (therapeutic activity) does not match that
of chemical drugs. However, LAB can be used as a natural adjuvant for chemotherapy, and they can be engineered to deliver therapeutic payloads in a targeted manner. Many creative approaches have been used to exploit natural bacterial processes and/or to harness bacteria as therapy vectors and cancer cell destroyers. Some of the safety concerns associated with genetic engineering need to be overcome; however,
we believe that LAB are an important new weapon in the fight against
cancer and other immune diseases.
Is it possible to perform quorum sensing amongst virus ?
ReplyDeleteYes there arw studies found that viruses use molecular signals that enable them to decide whether to kill ir infect the host cells.
DeleteYes,recent discovery shows certain viruses of gram-positive bacteria also use quorum sensing to communicate with each other The viruses also use short peptides as autoinducer to monitor virus population densit
DeleteViruses that infect bacteria known as bacteriophages have surveillance mechanisms that provide information on whether to stay dormant or attack, depending on the availability of fresh victims. But researchers have long thought that these processes were passive; the phages seemed to just sit back and listen, waiting for the bacterial distress signals to reach the fever pitch before taking action.
DeletePhages might speak only to their own kind , but they can listen in on other languages . Molecular biologist Bonnie Basler and her graduate students Justin Silpe have found that virus can use quorum sensing chemicals released by bacteria to determine when best to start multiplying. The virus can also use short peptides as autoinducer to monitor virus population density.
DeleteThis comment has been removed by the author.
ReplyDelete