You are encouraged to express your subject-related thoughts, opinions, and relevant microbiological content from authentic sources through this blog platform.
HAND HYGIENE: SOAP OR HAND SANITIZER Ever since the pandemic has begun, the utilization of hand sanitiser has increased multifold. Before the pandemic, most people were not even aware of sanitiser, but are sanitisers really worth the hype or the conventional hand-washing better? Everyone has a different opinion; some opine that sanitiser is better than soap, whereas others believe conventional hand-washing is better. According to multiple studies, sanitisers are most effective when the alcohol concentration is 60-95%. Sanitisers are handy. When soap and water are not accessible, sanitiser is the best alternative. However, sanitisers are not highly effective when the hands are visibly dirty or greasy. Also, it has been observed that bacteria have started to show tolerance towards low amounts of ethyl alcohol. Moreover, the alcohol in the sanitiser cause skin dryness. The lesser concentration of alcohol in sanitiser just inhibits the growth of germs instead of killing them. On the other hand, soap combined with water is by far the best option to get rid of microbes and chemicals from our hands. According to CDC, when we wash hands with soap and water, the surfactants in the soap remove dirt and microbes from the skin, and people tends to scrub hands more rigorously while washing hands with soap. Soap kills the microbes, binds them and then remove them from the skin with the help of water. To sum up, there is a saying that hand hygiene is imperative, regardless of what product you use.
Soap vs sanitizer vs antimicrobial soap . As we all discuss in our class .In my opinion also soap is more preferable than sanitizer and antimicrobial soap. This is because sanitizer its main function is to act against vegetative bacteria, fungi and lipid-containing viruses but not against spores. According to research also it is more effective in clinical areas. Rather than in day to day life because we all come in contact with oil and grease. Against this sanitizer does not work efficiently and second reason can be that it can create the problem of Alcohol poisoning in kids. If I talk about antimicrobial agent They definitely work against microorganism but it also create the problem of antimicrobial Resistance which is harmful for our body as well as for a our environment . That's why in my opinion soap is the best agent because according to its mechanism also it has hydrophilic and hydrophobic sides. The hydrophilic side is stick out in the water . In Hydrophobic side all the dirt , Germs, microbes and oil particle gets atteched.and Micelle form and remove the dust ,Germs ,microbes and the oil particle from the hand surface. Because of this pandemic we all get very much familiar with the process of hand cleaning with the soap. In case if anybody have any doubt about hand cleaning process with soap. I am writing its 6 steps :1 -Wet your hands with clean, running water. turn off the tap, and apply soap. 2 apply soap on your hands and wrist, try to cover your whole surface of your hand and wrist . 3-Lather and rub your hands together, Make sure to scrub all surfaces of your hands, fingertips, fingernails, and wrists. 4 -repeat the step 3 (scrubing) at least for 20 seconds. 5 -Rinse your hands and wrists under clean — preferably running — water. 6 Dry your hands and wrists with a clean towel, or let them air-dry.
Soap vs Sanitizers I agree with the popular opinion of soap being a better option, my belief however, stem from a much simpler point of view. We are all aware of the fact that our hands are made up thousands of microscopic ridges and grooves which provide perfect place for microscopes to hide. Both alcohol and soap are capable of removing germs by acting on the bi-lipid layer of viruses, however, since alcohol is a highly volatile liquid it is unlikely to be able to reach the microscopic ridges in our hands where the virus might be hiding. Soaps on the other hand work with water and should be able to cover more surface area highly effectively. The drying effect of alcohol and the gentler action of soaps also helps my stand.
E. coli – BUENO OR NO BUENO It is quite debatable whether E. coli is a good bacterium or not. E. coli is an abbreviation of Escherichia coli. Theodor Escherich, a German-American paediatrician, discovered E. coli. The “coli” in Escherichia coli means “from the colon”. This bacterium is generally present in the intestines of humans and animals. It acts as both our friend and our foe. As a friend – For more than a century, E. coli strain Nissle has been used as a probiotic and therapeutic agent. It is also used to treat inflammation. Additionally, it has been observed that the E. coli strain Nissle helps in the protection of human cells from other pathogenic strains of E. coli. Some strains of E. coli even help in the prevention of uncontrolled growth of harmful bacteria in large intestines. Moreover, they help in the breakdown and digestion of food. Although E. coli is not a prime bacterium in the gut, it is a very imperative bacterium. On the contrary, it has always been infamous for its pathogenicity. A person can get E. coli infection, if he/she comes in contact with the faeces or stool of humans or animals. Also, contaminated food and water can cause infections. The most infamous strain is O157:H7. Toxins produced by some E. coli strains are biological poisons. Some strains of E. coli, which are normal inhabitants of the gut, can create havoc in other parts of the body. The major categories in which pathogenic E. coli can be divided are Enterotoxigenic, Enteroinvasive, Enteropathogenic, Enteroaggressive and Enterohaemorrhagic. The symptoms of the E. coli infection are Nausea, stomach cramps, dehydration, diarrhoea, fatigue, etc. Currently, there is no specific cure for an E. coli infection. However, antibiotics aid in case of urinary tract infection but, they are not helpful in other cases and can even be harmful. For the prevention of the infection, several measures can be adopted, such as cook meat properly, clean anything that comes in contact with raw meat, and use pasteurized products. To conclude, in my opinion, the harmful characteristics of E. coli outweighs the beneficial characteristics.
Q) E. coli divides every 20 minutes. The starting value is 1 bacterial cell. After 24 hours, how many bacteria are present? Answer 24 hours = 24 x 60 = 1440 minutes Time for 1 generation is 20 minutes, So, in 1440 minutes bacterial cells divide 72 times (1440/20 = 72). Number of generations n = 72 So, 2^n; 2^72 = 4722366482869640000000 Initial bacterial cell is 1, so 1 x 4722366482869640000000 = 4722366482869640000000 cells
what if microorganism would absent ? Decomposers break down the dead remains of plants and animals and release the nutrients such as carbon, nitrogen etc. into the environment. In the absence of decomposers in the environment, this breakdown will not occur and hence, the nutrients will not be released. Due to this, plants will not get sufficient nutrients. Organisms will also not grow properly and some may even cease to exist because the carbon, nitrogen and other elements necessary to form cells will be insufficient. Microbes are hugely abundant, and that abundance, or lack of abundance, can affect multiple planetary boundaries. They, for example, take millions of tons of nutrients, such as nitrogen, out of the atmosphere every year and make that element available to other organisms, like plants, aiding in their growth. Of all the carbon removed from the atmosphere, microbes are responsible for 40% annually. Some scientists have called microbes “the most functionally important organisms on Earth,” and have recommended including microbes in climate policy research.
If microorganism gets disappeared from the earth ?
Microorganism plays a vital role in our life. If microorganism disappears it will create a negative impact on our life's as well as on the environment . Here I am describing some negative consequences that can be created due to extinction of microbes on earth.
1 immense accumulation of waste : As we all know that bacteria play a major role in decomposition of organic waste. Bacterial digestion is the process of bacteria consuming organic matter. The bacteria feed on the organic waste, deriving nutrition for growth and reproduction. Using complex chemical reactions, the organic waste is metabolized down to water and carbon dioxide (the final metabolic waste products), providing the bacteria with energy to sustain their life. But if bacteria get disappeared from the Earth it can create a immense problem of accumulation of waste.
2 Ruminant animals would starve - Ruminant animals can't digest cellulose, the main compound that makes up plant cell walls, on their own. They rely on gut microbes that can break down cellulose, allowing the animal to digest and absorb the nutrients from the plant. A loss of microbes would mean that they'd starve.
3 - We wouldn't be able to digest our food properly without our gut bacteria. It will ultimate lead to starvation and human will also die.
4 - Can create imbalance in biogeochemical cycles - Microbes plays a vital role in biogeochemical cycling of nutrients. They converts carbon and nitrogen into organic compound .
5 - It can create disturbance in food chain and food Web - As Bacteria and other microbes plays an important role in food chains and food webs as they are DECOMPOSERS which acts in the last stage of food chain. These micro-organisms like bacteria cause the breakdown of energy rich organic compounds. Without microorganisms this important process of environment get disturbed .
By this points I can conclude that microorganism plays a vital role in our life and without them We can't survive as well as our surrounding also get disturbed .
A WORLD WITHOUT MICROBES !! What would happen if microbes completely disappeared from the earth? No bacteria, no fungus, no algae, etc. As we are facing this pandemic, even the imagination of the world without microbes seems so fascinating. But, can we survive in a world without microbes? On the upside, there would be no infectious diseases. No Ebola! No tuberculosis, etc. But what could possibly go wrong? So, here the good news end. Firstly, microorganisms, specifically, algae play an imperative role in oxygen production. Around 50 to 80 percent of oxygen is produced by the phytoplankton (marine algae). Also, some bacteria help in oxygen production. So, if microbes disappeared, the entire system of oxygen production by microbes would collapse. Secondly, microbes play a quintessential role in the digestion of food in ruminant animals. Microbes help in the digestion of cellulose. Without gut microbes, the animals would starve and die. Thirdly, the disappearance of microbes directly affects the ecosystem. The animals who are dependent on microorganisms would starve. For instance, in the deep oceans, many animals like shellfish, worms, etc., depend on bacteria, so the vanishing of bacteria would disturb the food web. Fourthly, microbes are great decomposers, as they break down an enormous amount of accumulating waste. For instance, in composting, microbes help in the breakdown of waste, and the perishing of microbes would cease the decomposition and recycling of waste. Likewise, microbes play a crucial role in our daily lives as humans are symbiotic organisms. To sum up, Louis Pasteur once said, “Life would not long remain possible in the absence of microbes.”
What if all microbes disappears : If all microbes were to disappear, the future of life on the planet would parallel a world without Bacteria and Archaea, except that the myriad environmental impacts would be more acute. Even more so than in a Bacteria- and Archaea-free world, most biogeochemical cycling would cease; human and animal waste would accumulate rapidly. There would be very little decomposition apart from disassociation and inherent catabolic enzymatic activity. The essential role that microbes play in biomass recycling would not be served even by fungi or protists, resulting in a rapid exhaustion of available macronutrients and micronutrients in terrestrial and aquatic environments. Living food sources would be increasingly difficult to find. Most ruminant livestock would starve without microbial symbionts, and plants would rapidly deplete nitrogen, cease photosynthesis, and then die. Intensive human intervention required to produce and distribute sufficient vitamins, plant fertilizers, and food sources would likely overwhelm ingenuity in the face of mounting environmental, ecological, and humanitarian disaster. As with a Bacteria- and Archaea-free world, small pockets of humans and other animals (e.g., insects) would survive for a time, decades or centuries even, but long-term survival of most eukaryotes would be doubtful. (Reference from NCBI) roll no: 21MBT020
ROLL NO. 21MMB013 WHAT IF MICROBES DISAPPEAR FROM EARTH Microbes are everywhere they can be in soil, air, water, food, including our skin, mouth, and our gut. They help in recycling waste and decomposing dead organic matter of life forms. But what would had happen if all microbes- bacteria, fungus, virus, protista disappear from earth.in starting, immediate consequences may be manageable but in course of time it would get much worse and eventually all life on earth would cease to exist.
As a good news microbes all over the world causing various diseases and infection would vanish. Hence no ebola no common cold and flu! This may seem like best thing ever happen to humans but eventually lose of microbes woud have dire consequences for humans, animals, plants and other life forms.
For example, gut bacteria- microbes present inside our digestive system helps in absorbing energy from food and breaks down complex molecules as cellulose present in meat and vegetables. If gut bacteria are removed from our body we would experience decreased bowel movement leading to whole host of problem and also weakens our immune system. If all microbes disappear , we would have to make sure we stay germ free for our entire life. Sudden exposure to life outside the bubble would probably kill us.
Q) What is the maximum bacterial cell density that can be achieved in 1ml broth? Answer: The cell density depends on the type of broth and the type of bacteria. According to multiple studies, the maximum bacterial cell density that can be achieved in 1ml broth is somewhere around 10e9 to 10e12.
Q WHAT IS THE MAXIMUM BACTERICAL CELL GROWTH IN 1 ML BORTH ?
ans : In my opinion , It depends on the type of bacteria we are working with because every type of bacteria has a specific generation time and secondly it can depend on the type of broth we are working on. If we add some growth factors in the broth, then the growth of the culture will increase clearly .
Question : why we cannot cultivate some organisms?
May be some organisms depend on each other for growth or Some organisms produce inhibitory substances in sample, and sometimes essential Nutrients for the microorganisms is not present in the medium...
Question:- How does a spectrophotometer measure OD in a sample when most bacteria are colourless? Beer-Lambert's law only holds when the particles are soluble (when all the photons of light have an equal chance of absorption by sample), however microbes are insoluble. How is turbidity measured by a spectrophotometer then?
Answer:- Most bacteria are unpigmented and hence cannot absorb any (or very little light if they are slightly coloured) light. Instead, these microbes scatter the light in various different directions and only a small amount of it reaches the photoelectric cell of the spectrophotometer. The denser the microbial sample, the more light would be scattered. The amount of light transmitted through cuvette containing bacterial sample would be therefore, less than that through the blank cuvette. Hence, here the OD is not the absorbance but the amount of light scattered. Pigmented microbes absorb and scatter light.
The spectrophotometer works on the concept of Beer-Lambert's law. The Beer-Lambert's law is a linear relation of absorbance and the concentration of the absorbing molecule when it is soluble in the solution. Bacteria are insoluble, however in practice, it has been seen that even when there is no absorbance, the Beer-Lambert's law holds good for low density suspensions (the proportionality of OD and cell density exists only when OD is less than 0.4). High density cultures that go beyond this limit would have to first be diluted after which their OD can be calculated.
Question- why spectrophotometry used for bacteria? Beer Lambert law is applicable for soluble particles only , how it can be used for microorganisms?
Answer- spectrophotometry is a method used to measure about the amount of light absorbed by chemical substances. A beams of light is passed through the sample solution. In case of microorganisms instead of absorbing it scatters the light. The amount of light scattered is considered as the optical density. Microorganisms are measured in the terms of turbidity. Spectrophotometry works on the Beer Lambert law equation. In case of bacteria because they are insoluble it gives density of the suspension.
Q - If most of the bacteria are transparent than how we are able to measure OD of a given sample in spectrophotometer ?
Ans - As most of the bacteria are colorless , the bacterial cell density we are measuring its light gets scattered (absorbance not occurred ). Because most bacteria are transparent , the amount of light they absorb is negligible and most of the reduction in transmitted light is due to light scattering by the cells. Its scattering also depends upon microbial density ,more the density ; more the light will scattered . So the OD we get is the OD of scattering not the OD of absorbance in spectrophotometer.
Q- If beer-lambert's law is applicable for soluble particle so how we are able to measure microbial turbidity in spectrophotometer ? [As microbes are insoluble ]
Lambert beer law is only applicable for soluble particle and as we know that microbes are insoluble but microbes gives density of suspension. That's why we are able to calculate OD in spectrophotometer .
Q) Can spectrophotometer be used to determine the concentration of “colourless” solutes such as E. coli? Spectrophotometer is an instrument which measures absorbance at various wavelengths. The working principle of Spectrophotometer is based on Beer-Lambert’s Law. The Beer-Lambert’s Law states that the amount of light absorbed by a coloured solution is directly proportional to the concentration of the solute in the solution and the thickness of the solution under analysis. In case of coloured solutions, when light reaches the cuvette, some part of light is reflected, some part of light is absorbed and the rest of the light is transmitted and detected by the photoelectric cell. But, in the case of colourless bacteria such as E. coli the absorption is marginal. However, the light is scattered by the bacterial cells in the solution due to which scattered light does not reach the photoelectric cell which eventually weakens the electric signal.
Q. The beer Lambert law is applicable for only soluble particle but bacteria is insoluble so how it can be used for Microorganisms &how measure OD for Microorgani?
Cell suspensions are turbid. Cells absorb and scatter the light. The higher the cell concentration, the higher the turbidity. Spectrophotometerscan measure intensity of light very accurately. The cell culture is placed in a transparent cuvette and the absorption is measured relative to medium alone. Optical density (OD) is directly proportional to the biomass in the cell suspension in a given range that is specific to the cell type. Using spectrophotometry for measuring the turbidity of cultures is known as turbidometry. This has made spectrophotometry the methods of choice for measurements of bacterial growth and related applications. Spectrophotometry's drawback is its inability to provide an absolute count or distinguish between living and dead cell.
Q:-most of the bacteria are colourless so how we are able to measure OD of a given sample in spectrophotometer ? OD is measured in a spectrophotometer. The principle is that most of the light scattered by the cells no longer reaches the photoelectric cell, so that the electric signal is weaker than with a cell-free cuvette.The OD of the culture is not an absorption primarily ( in case of dissolved dye) . Cells of many bacteria are colourless & real light absorption is marginal so the most appropriate term would be turbidity . The photoelectric cell doesnot know what causes the decrease in light intensity its only notices less light which is displayed as a number ( extinction value usually)
Q -How we get OD of decline phase as in decline phase bacteria are undergo lyses or death ?
Ans - In decline phase microbial cell undergo cell death .But we still get low OD .By two hypothesis we can explain this :-
1 - Cell undergo death which leads to autolysis . Autolysis is the enzymatic digestion of cells by the action of its own enzymes, and it mostly occurs in dying or dead cells.The leak cellular content of lysed cell released out in medium which is utilised by unlysed cells.
2- Cells which get survive undergoes dormant stage,in which cell is viable but non culturable
Therefore we get OD because of autolysis and dormant stage of cell . so when light passes through unlysed cells and dormant stage cells we get OD . Also the rate of decline is more than the rate of growth in decline phase. so OD which we get is low .
Question :when the cell number increase, OD also increase but when cell enter into death phase, no of cell remain same then what is reason of decrease in OD?
Ans:In log phase, cell number increase so the amount of light scattered and transmitted by cell also increase that's why OD increase but when cell enter into death phase, it burst and release it's cellular content in the suspension and get settled due to gravity force.OD is given by suspended cell in solution. Settled cell can not give it.due to this reason, light scattered by cell also decrease. That's why cell number remain same but OD decrease in death phase.
Q. Why does the O.D. decrease when the bacteria enters the death phase?
The conversion factor from OD to cell number or cell mass concentration drops after death because cell membrane is damaged and cytoplasm leaks out, as a result refractive index decreases and therefore OD drops because of smaller scattering of light.
IF we are not able to cultivate some of the Extremophiles in laboratory then how we can do research on them or do study about them? Researchers have invented methods to study microbes that thrive in the world’s most inhospitable environments. Microbes cling to life in some of Earth’s most extreme environments, from toxic hot springs to high-altitude deserts. These ‘extremophiles’ include organisms that can survive near-boiling heat or near-freezing cold, high pressure or high salt, as well as environments steeped in acids, alkalis, metals or radioactivity. In 2014, Scott Tighe, a microbiologist at the University of Vermont in Burlington, gathered international collaborators for an ongoing initiative known as the Extreme Microbiome Project (XMP). The researchers hope to find genes that might indicate how extremophiles survive and whether they might make compounds that could work as antibiotics. In their search for new microbes to analyse, the scientists have travelled to extreme locales, including the toxic hot springs of Ethiopia’s Danakil Depression, which are loaded with salt, acids and heavy metals, and a flaming gas crater in Turkmenistan. But their main challenges arose back in the lab: “Massive hurdles, actually,” says Tighe. Microbes tough enough to withstand extreme conditions resisted scientists’ attempts to break them open and recover their DNA. So Tighe and the XMP team developed a six-enzyme cocktail — now commercially available as MetaPolyzyme — to break down any cell surface they might come across, adding detergents and organic solvents to collect nucleic acid on magnetic beads1. “It got to be a fairly exotic DNA-extraction technique,” says Tighe. Thus armed, the researchers are working through a freezer full of samples, says Tighe. DiRuggiero has also worked with anaerobic hyperthermophiles, which grow at high heat and in the absence of oxygen. To culture them, she used heat-resistant, NASA-made culture jars in an incubator set to 95 °C — so toasty, the team jokingly called it the “pizza oven”. Standard agar in plastic Petri dishes would melt, so scientists turn to glass dishes packed with a gellan-gum derivative called Gelrite, which can withstand the heat.
Buzz Baum, a cell biologist at the Medical Research Council Laboratory for Molecular Biology in Cambridge, UK, is interested in cell division in the thermophile and acidophile Sulfolobus acidocaldarius. But live cultures cool as quickly as a cup of tea on the microscope stage, says Baum, and the microbes go into suspended animation. The team decided to borrow a technique used in polymerase chain reaction machines, to warm the cultures from the top as well as the bottom. They recruited a lab member’s father and brother, both aerospace engineers, to fabricate a chamber out of aircraft aluminium. The researchers have published diagrams for this ‘Sulfoscope’, but any double-heated chamber should do, says Baum. The system allows the team to investigate proteins that maintain symmetrical cell division.
Ans: Extremophiles are organisms capable of living in an extreme environment. An extreme environment is one in which most organisms would not be able to live and therefore is described as uninhabitable to most organisms. It could be due to extremes in temperature, pressure, or salinity that would be detrimental to most living organisms. However, there are still certain organisms, such as extremophiles, that are able to survive and thrive in such conditions. Extremophiles are typically unicellular organisms belonging to the domain Archaea.
Its study is important due to following reasons-
1:physicochemical parameters defining life on Earth and may provide insight into how life on Earth originated. The postulations that extreme environmental conditions existed on primitive Earth and that life arose in hot environments have led to the theory that extremophiles are vestiges of primordial organisms and thus are models of ancient life.
2:Extremophiles are of biotechnological interest, as they produce extremozymes, defined as enzymes that are functional under extreme conditions. Extremozymes are useful in industrial production procedures and research applications because of their ability to remain active under the severe conditions (e.g., high temperature, pressure, and pH) typically employed in these processes.
3:Extremophiles are also of research importance in the field of astrobiology. Extremophiles that are active at cold temperatures are of particular interest in this field, as the majority of the bodies in the solar system are frozen. The discovery of microorganisms with unusual biochemical properties, such as the ability to use arsenic rather than phosphorus for their growth, are also of interest to astrobiology, since extraterrestrial environments may favour life-forms that use or are built from elements not typically found in life on Earth . Thus, understanding the limits of life on Earth provides scientists with information about the possible existence of extraterrestrial life and provides clues about where and how to search for life on other solar bodies.
Q.what is important of Extermophiles and why we study of Extermophiles?
-Extremophiles offer numerous advantages including (1) the absence of contaminants in open door cultures subjected to physicochemical pressure, (2) their potential adaptation to industrial environments such as presence of toxins, radioactive elements or extreme pH and consequently their potential use for the biocatalysis of effluents and (3) their ability to produce enzymes with biotechnological applications.
-The study of extremophiles provides an understanding of the physicochemical parameters defining life on Earth and may provide insight into how life on Earth originated. ... Extremophiles are also of research importance in the field of astrobiology.
Que:How can we conduct reserch on extremophiles as we are unable to grow them in vitro?
Ans:These versatile organisams called extremophiles are able to grow and survive in harsh condition.
1.For research,scientist attempts to break down cellwall and recover their dna so they developed 6 enzyme togather called cocktail commercially available as meta polyzyme to breakdown cell surface by adding detergents to collect nucleic acid. 2. scientist has worked with anerobic hyperthermophiles. To cultivate them, they used heat resistant culture jar that is able to withstand 95•c in incubator. At such temparature standard agar in petridish would melt so scientist wrapped petri dishes with gelarite which can tolerate high temparature. 3.some scientist also manipulate gene. For that they create gene they want to use and isolate relative plasmid and then insert this gene into plasmid and then transfer to extremophiles. Some extremophiles can take up this plasmid from surrounding by process called transformation. 4.They also use electroporation, a pulse of electricity that creat hole in cell's membrane. 5. They have also tried to determine methylation pattern on extremophiles 's genome. That's important because microorganisams Will often destroy nucleic acid that have wrong pattern as a protection from invaders. Scientist modify those methylation system in ecoli to make new dna match that of the host. So that's how scientist find various way to study and reserch about extremophiles
Question:- Which is better:- Hand Sanitizer or Regular Soap
Answer:- Hand sanitizer can disinfect it at least 60% alcohol but soap and water is the most effective way to remove all kinds of germs, dirt and chemicals as applying hand sanitizer may e easier but it don't eliminate everything even the ones with sufficient alcohol cannot remove all types of bacteria and viruses. Soap and water are more effective at removing such illness causing germs because soap molecules themselves are effective at destroying the surface membranes of some bacteria and viruses in addition the lathering of hands and scrubbing thoroughly creates friction that helps in cleaning dirt away. Hand sanitizer will work well in case where hands are not heavily soiled or greasy but in work where people handle equipment , food or play sports-sanitizer can't clean thoroughly enough. Moreover it is ineffective if too little is applied or wiped off before it has dried completely.
Question:- Is Escherichia coli a Good bacteria or Bad bacteria?
Answer:- Escherichia coli occurs naturally in the intestine of human being and animals. Most Escherichia coli are harmless and actually are an important part of healthy human intestinal tract, it prevents the uncontrolled growth of harmful bacteria in large intestine. However some E.coli strains are pathogenic, which can cause illness either diarrhea or illness outside of the intestinal tract.
Question:- Escherichia coli divides every 20 minutes.The starting value is 1 bacterial cell. After 24 hours how many bacteria are present?
Answer:- 24 hours = 24x60= 1440 minutes 1 generation- 20 minutes, (2^n = 2^= 20 minutes) So according to that in 1440 minutes bacteria will divide 72 times (1440/20 = 72) So number of generation is 72 then (2^n) 2^72= 4722366482869640000000. This will be total number of bacteria are present after 24 hours.
Answer:- If all microbes will disappear the future of life on planet would be a world without bacteria and archaea. Then uncountable environmental impacts would be more acute. Also most biogeochemical cycling would be ceased. Humans and animals waste would be accumulated in high amount, there would be very little decomposition,apart from inherent catabolic enzymatic activity. The essential role that microbes play in biomass recycling would not be served even by fungi and protist and it will result in a rapid depletion of nutrients from environment. As with bacteria and archaea free world and with humans and other animals would survive for sometime but long term survival of most eukaryotes may be not possible.
Question:- Can spectrometer be used to determine the concentration of colourless solutes such as Escherichia coli ?
Answer:- Spectrophotometry relies on the absorbance of light by the solution. It works by sending a beam of light through a cuvette filled with the solution, and, depending on how much light passes through, the spectrophotometer can measure the amount of light/photons that was/were absorbed. If the solution is colorless, it absorbs no light so, in the case of colourless bacteria such as Eschierchia coli the absorption is marginal. However, the light is scattered by the bacterial cells in the solution due to which scattered light does not reach the photoelectric cell which eventually weakens the electric signal.
Question:- What is the maximum bacterial cell density that can be achieved in 1ml broth?
Answer:- It will depends on type of broth we are using and also type of bacteria we are working with. Theoretically we can fit 10e12 cells maximum assuming no water and maximal packing density.
Extremophiles can survive in boiling water, freezing cold environments, high salt, high pressure, etc. Scientists are curious to explore the world of extremophiles. Identifying, culturing and observing extremophiles is a quite tedious process. However, scientists have found certain methods to observe them in laboratories. First, they had tried to find and manipulate the genes that help extremophiles live in extreme conditions. But to find those genes, they need to extract DNA from the extremophiles, and it is really difficult to recover DNA from them as they can withstand extreme conditions, so it is tedious to break extremophiles to recover DNA. Although, an enzyme cocktail has been developed, which break down any cell surface it comes in contact with. Different extremophile needs different conditions. For instance, halophiles grow under high salt conditions, so salt is added to the culture media. In the case of thermophiles, the microbes need high temperatures, and the major problem that scientists face during growing thermophiles is that the Petri plate melts at a temperature that is optimum for extremophiles. To solve this problem, NASA had developed jars that can handle 95 degrees temperature. Likewise, different techniques have been developed to grow extremophiles in the laboratory.
Q.- why large no.of microorganisms mainly found in large intestine??
Recent research on obesity, in mice and humans, has demonstrated that microbes of the intestine can have an important influence on host energy balance.
Human gut microbes perform many metabolic functions that our own bodies cannot carry out, creating a symbiotic relationship. For example, we consume plant polysaccharides that are rich in xylan-, pectin- and arabinose-containing carbohydrate structures, which we are unable to digest. Encoded in the genomes of gut microbiota, however, are a large number of glycoside hydrolases, which break down these plant products and convert them into usable energy sources
Why 70% alcohol is used for disinfection ? 70% alcohol is ideal for more powerful solutions. Pure alcohol coagulates proteins when in contact. Suppose pure alcohol is poured into a unicellular organism. Alcohol penetrates the cell wall of living organisms in all directions and directly coagulates proteins in the cell wall. A ring of coagulated protein prevents alcohol from penetrating extracellularly and prevents coagulation. At this point, the cell is inactive, but not dead. Under favorable conditions, the cells then begin to function. When 70% alcohol is poured into a unicellular organism, the diluted alcohol also coagulates the protein, but slowly and completely penetrates the cell before coagulation blocks. After that, the whole cell coagulates and the organism dies.
Why 70% alcohol is used for disinfection and not absolute alcohol? Isopropyl alcohol is fast antibacterial against bacteria, fungi, and viruses, especially in solutions containing 60 percent to 90 percent alcohol and 10 to 40 percent filtered water. When alcohol concentrations fall below 50%, their disinfectant properties rapidly deteriorate. Notably, increased alcohol concentrations do not result in better bactericidal, virucidal, or fungicidal effects.
When using isopropyl alcohol to kill or stop harmful bacteria, the presence of water is critical. Water is a catalyst that aids in the denaturation of the proteins in vegetative cell membranes. 70% IPA solutions penetrate the cell wall more thoroughly, allowing all proteins to coagulate and the microbe to perish. Evaporation is slowed by the presence of extra water, which increases surface contact duration and effectiveness. Overdoses with isopropyl alcohol.
This comment has been removed by the author.
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteHAND HYGIENE: SOAP OR HAND SANITIZER
ReplyDeleteEver since the pandemic has begun, the utilization of hand sanitiser has increased multifold. Before the pandemic, most people were not even aware of sanitiser, but are sanitisers really worth the hype or the conventional hand-washing better? Everyone has a different opinion; some opine that sanitiser is better than soap, whereas others believe conventional hand-washing is better.
According to multiple studies, sanitisers are most effective when the alcohol concentration is 60-95%. Sanitisers are handy. When soap and water are not accessible, sanitiser is the best alternative. However, sanitisers are not highly effective when the hands are visibly dirty or greasy. Also, it has been observed that bacteria have started to show tolerance towards low amounts of ethyl alcohol. Moreover, the alcohol in the sanitiser cause skin dryness. The lesser concentration of alcohol in sanitiser just inhibits the growth of germs instead of killing them.
On the other hand, soap combined with water is by far the best option to get rid of microbes and chemicals from our hands. According to CDC, when we wash hands with soap and water, the surfactants in the soap remove dirt and microbes from the skin, and people tends to scrub hands more rigorously while washing hands with soap. Soap kills the microbes, binds them and then remove them from the skin with the help of water.
To sum up, there is a saying that hand hygiene is imperative, regardless of what product you use.
This comment has been removed by the author.
ReplyDeleteroll no -21mmb006
ReplyDeletename- gargi h sharma
Soap vs sanitizer vs antimicrobial soap .
As we all discuss in our class .In my opinion also soap is more preferable than sanitizer and antimicrobial soap. This is because sanitizer its main function is to act against vegetative bacteria, fungi and lipid-containing viruses but not against spores. According to research also it is more effective in clinical areas. Rather than in day to day life because we all come in contact with oil and grease. Against this sanitizer does not work efficiently and second reason can be that it can create the problem of Alcohol poisoning in kids.
If I talk about antimicrobial agent They definitely work against microorganism but it also create the problem of antimicrobial Resistance which is harmful for our body as well as for a our environment .
That's why in my opinion soap is the best agent because according to its mechanism also it has hydrophilic and hydrophobic sides. The hydrophilic side is stick out in the water . In Hydrophobic side all the dirt , Germs, microbes and oil particle gets atteched.and Micelle form and remove the dust ,Germs ,microbes and the oil particle from the hand surface. Because of this pandemic we all get very much familiar with the process of hand cleaning with the soap. In case if anybody have any doubt about hand cleaning process with soap.
I am writing its 6 steps :1 -Wet your hands with clean, running water. turn off the tap, and apply soap.
2 apply soap on your hands and wrist, try to cover your whole surface of your hand and wrist .
3-Lather and rub your hands together, Make sure to scrub all surfaces of your hands, fingertips, fingernails, and wrists.
4 -repeat the step 3 (scrubing) at least for 20 seconds. 5 -Rinse your hands and wrists under clean — preferably running — water. 6 Dry your hands and wrists with a clean towel, or let them air-dry.
Soap vs Sanitizers
ReplyDeleteI agree with the popular opinion of soap being a better option, my belief however, stem from a much simpler point of view. We are all aware of the fact that our hands are made up thousands of microscopic ridges and grooves which provide perfect place for microscopes to hide. Both alcohol and soap are capable of removing germs by acting on the bi-lipid layer of viruses, however, since alcohol is a highly volatile liquid it is unlikely to be able to reach the microscopic ridges in our hands where the virus might be hiding. Soaps on the other hand work with water and should be able to cover more surface area highly effectively.
The drying effect of alcohol and the gentler action of soaps also helps my stand.
E. coli – BUENO OR NO BUENO
ReplyDeleteIt is quite debatable whether E. coli is a good bacterium or not. E. coli is an abbreviation of Escherichia coli. Theodor Escherich, a German-American paediatrician, discovered E. coli. The “coli” in Escherichia coli means “from the colon”. This bacterium is generally present in the intestines of humans and animals. It acts as both our friend and our foe.
As a friend – For more than a century, E. coli strain Nissle has been used as a probiotic and therapeutic agent. It is also used to treat inflammation. Additionally, it has been observed that the E. coli strain Nissle helps in the protection of human cells from other pathogenic strains of E. coli.
Some strains of E. coli even help in the prevention of uncontrolled growth of harmful bacteria in large intestines. Moreover, they help in the breakdown and digestion of food. Although E. coli is not a prime bacterium in the gut, it is a very imperative bacterium.
On the contrary, it has always been infamous for its pathogenicity. A person can get E. coli infection, if he/she comes in contact with the faeces or stool of humans or animals. Also, contaminated food and water can cause infections. The most infamous strain is O157:H7. Toxins produced by some E. coli strains are biological poisons. Some strains of E. coli, which are normal inhabitants of the gut, can create havoc in other parts of the body.
The major categories in which pathogenic E. coli can be divided are Enterotoxigenic, Enteroinvasive, Enteropathogenic, Enteroaggressive and Enterohaemorrhagic.
The symptoms of the E. coli infection are Nausea, stomach cramps, dehydration, diarrhoea, fatigue, etc. Currently, there is no specific cure for an E. coli infection. However, antibiotics aid in case of urinary tract infection but, they are not helpful in other cases and can even be harmful. For the prevention of the infection, several measures can be adopted, such as cook meat properly, clean anything that comes in contact with raw meat, and use pasteurized products.
To conclude, in my opinion, the harmful characteristics of E. coli outweighs the beneficial characteristics.
Q) E. coli divides every 20 minutes. The starting value is 1 bacterial cell. After 24 hours, how many bacteria are present?
ReplyDeleteAnswer
24 hours = 24 x 60 = 1440 minutes
Time for 1 generation is 20 minutes,
So, in 1440 minutes bacterial cells divide 72 times (1440/20 = 72).
Number of generations n = 72
So, 2^n; 2^72 = 4722366482869640000000
Initial bacterial cell is 1, so
1 x 4722366482869640000000 = 4722366482869640000000 cells
what if microorganism would absent ?
ReplyDeleteDecomposers break down the dead remains of plants and animals and release the nutrients such as carbon, nitrogen etc. into the environment. In the absence of decomposers in the environment, this breakdown will not occur and hence, the nutrients will not be released. Due to this, plants will not get sufficient nutrients. Organisms will also not grow properly and some may even cease to exist because the carbon, nitrogen and other elements necessary to form cells will be insufficient.
Microbes are hugely abundant, and that abundance, or lack of abundance, can affect multiple planetary boundaries. They, for example, take millions of tons of nutrients, such as nitrogen, out of the atmosphere every year and make that element available to other organisms, like plants, aiding in their growth. Of all the carbon removed from the atmosphere, microbes are responsible for 40% annually. Some scientists have called microbes “the most functionally important organisms on Earth,” and have recommended including microbes in climate policy research.
This comment has been removed by the author.
ReplyDeleteIf microorganism gets disappeared from the earth ?
ReplyDeleteMicroorganism plays a vital role in our life. If microorganism disappears it will create a negative impact on our life's as well as on the environment .
Here I am describing some negative consequences that can be created due to extinction of microbes on earth.
1 immense accumulation of waste : As we all know that bacteria play a major role in decomposition of organic waste. Bacterial digestion is the process of bacteria consuming organic matter. The bacteria feed on the organic waste, deriving nutrition for growth and reproduction. Using complex chemical reactions, the organic waste is metabolized down to water and carbon dioxide (the final metabolic waste products), providing the bacteria with energy to sustain their life. But if bacteria get disappeared from the Earth it can create a immense problem of accumulation of waste.
2 Ruminant animals would starve - Ruminant animals can't digest cellulose, the main compound that makes up plant cell walls, on their own. They rely on gut microbes that can break down cellulose, allowing the animal to digest and absorb the nutrients from the plant.
A loss of microbes would mean that they'd starve.
3 - We wouldn't be able to digest our food properly without our gut bacteria. It will ultimate lead to starvation and human will also die.
4 - Can create imbalance in biogeochemical cycles - Microbes plays a vital role in biogeochemical cycling of nutrients. They converts carbon and nitrogen into organic compound .
5 - It can create disturbance in food chain and food Web - As Bacteria and other microbes plays an important role in food chains and food webs as they are DECOMPOSERS which acts in the last stage of food chain. These micro-organisms like bacteria cause the breakdown of energy rich organic compounds. Without microorganisms this important process of environment get disturbed .
By this points I can conclude that microorganism plays a vital role in our life and without them We can't survive as well as our surrounding also get disturbed .
A WORLD WITHOUT MICROBES !!
ReplyDeleteWhat would happen if microbes completely disappeared from the earth? No bacteria, no fungus, no algae, etc. As we are facing this pandemic, even the imagination of the world without microbes seems so fascinating. But, can we survive in a world without microbes?
On the upside, there would be no infectious diseases. No Ebola! No tuberculosis, etc.
But what could possibly go wrong?
So, here the good news end.
Firstly, microorganisms, specifically, algae play an imperative role in oxygen production. Around 50 to 80 percent of oxygen is produced by the phytoplankton (marine algae). Also, some bacteria help in oxygen production. So, if microbes disappeared, the entire system of oxygen production by microbes would collapse.
Secondly, microbes play a quintessential role in the digestion of food in ruminant animals. Microbes help in the digestion of cellulose. Without gut microbes, the animals would starve and die.
Thirdly, the disappearance of microbes directly affects the ecosystem. The animals who are dependent on microorganisms would starve. For instance, in the deep oceans, many animals like shellfish, worms, etc., depend on bacteria, so the vanishing of bacteria would disturb the food web.
Fourthly, microbes are great decomposers, as they break down an enormous amount of accumulating waste. For instance, in composting, microbes help in the breakdown of waste, and the perishing of microbes would cease the decomposition and recycling of waste.
Likewise, microbes play a crucial role in our daily lives as humans are symbiotic organisms.
To sum up, Louis Pasteur once said, “Life would not long remain possible in the absence of microbes.”
What if all microbes disappears :
ReplyDeleteIf all microbes were to disappear, the future of life on the planet would parallel a world without Bacteria and Archaea, except that the myriad environmental impacts would be more acute. Even more so than in a Bacteria- and Archaea-free world, most biogeochemical cycling would cease; human and animal waste would accumulate rapidly. There would be very little decomposition apart from disassociation and inherent catabolic enzymatic activity. The essential role that microbes play in biomass recycling would not be served even by fungi or protists, resulting in a rapid exhaustion of available macronutrients and micronutrients in terrestrial and aquatic environments. Living food sources would be increasingly difficult to find. Most ruminant livestock would starve without microbial symbionts, and plants would rapidly deplete nitrogen, cease photosynthesis, and then die. Intensive human intervention required to produce and distribute sufficient vitamins, plant fertilizers, and food sources would likely overwhelm ingenuity in the face of mounting environmental, ecological, and humanitarian disaster. As with a Bacteria- and Archaea-free world, small pockets of humans and other animals (e.g., insects) would survive for a time, decades or centuries even, but long-term survival of most eukaryotes would be doubtful.
(Reference from NCBI)
roll no: 21MBT020
ROLL NO. 21MMB013
ReplyDeleteWHAT IF MICROBES DISAPPEAR FROM EARTH
Microbes are everywhere they can be in soil, air, water, food, including our skin, mouth, and our gut. They help in recycling waste and decomposing dead organic matter of life forms. But what would had happen if all microbes- bacteria, fungus, virus, protista disappear from earth.in starting, immediate consequences may be manageable but in course of time it would get much worse and eventually all life on earth would cease to exist.
As a good news microbes all over the world causing various diseases and infection would vanish. Hence no ebola no common cold and flu! This may seem like best thing ever happen to humans but eventually lose of microbes woud have dire consequences for humans, animals, plants and other life forms.
For example, gut bacteria- microbes present inside our digestive system helps in absorbing energy from food and breaks down complex molecules as cellulose present in meat and vegetables. If gut bacteria are removed from our body we would experience decreased bowel movement leading to whole host of problem and also weakens our immune system. If all microbes disappear , we would have to make sure we stay germ free for our entire life. Sudden exposure to life outside the bubble would probably kill us.
Q) What is the maximum bacterial cell density that can be achieved in 1ml broth?
ReplyDeleteAnswer:
The cell density depends on the type of broth and the type of bacteria. According to multiple studies, the maximum bacterial cell density that can be achieved in 1ml broth is somewhere around 10e9 to 10e12.
This comment has been removed by the author.
ReplyDeleteQ WHAT IS THE MAXIMUM BACTERICAL CELL GROWTH IN 1 ML BORTH ?
ReplyDeleteans : In my opinion , It depends on the type of bacteria we are working with because every type of bacteria has a specific generation time and secondly it can depend on the type of broth we are working on. If we add some growth factors in the broth, then the growth of the culture will increase clearly .
This comment has been removed by the author.
ReplyDeleteQuestion : why we cannot cultivate some organisms?
ReplyDeleteMay be some organisms depend on each other for growth or Some organisms produce inhibitory substances in sample, and sometimes essential Nutrients for the microorganisms is not present in the medium...
Question:- How does a spectrophotometer measure OD in a sample when most bacteria are colourless? Beer-Lambert's law only holds when the particles are soluble (when all the photons of light have an equal chance of absorption by sample), however microbes are insoluble. How is turbidity measured by a spectrophotometer then?
ReplyDeleteAnswer:- Most bacteria are unpigmented and hence cannot absorb any (or very little light if they are slightly coloured) light. Instead, these microbes scatter the light in various different directions and only a small amount of it reaches the photoelectric cell of the spectrophotometer. The denser the microbial sample, the more light would be scattered. The amount of light transmitted through cuvette containing bacterial sample would be therefore, less than that through the blank cuvette. Hence, here the OD is not the absorbance but the amount of light scattered. Pigmented microbes absorb and scatter light.
The spectrophotometer works on the concept of Beer-Lambert's law. The Beer-Lambert's law is a linear relation of absorbance and the concentration of the absorbing molecule when it is soluble in the solution. Bacteria are insoluble, however in practice, it has been seen that even when there is no absorbance, the Beer-Lambert's law holds good for low density suspensions (the proportionality of OD and cell density exists only when OD is less than 0.4). High density cultures that go beyond this limit would have to first be diluted after which their OD can be calculated.
Question- why spectrophotometry used for bacteria? Beer Lambert law is applicable for soluble particles only , how it can be used for microorganisms?
ReplyDeleteAnswer- spectrophotometry is a method used to measure about the amount of light absorbed by chemical substances. A beams of light is passed through the sample solution. In case of microorganisms instead of absorbing it scatters the light. The amount of light scattered is considered as the optical density. Microorganisms are measured in the terms of turbidity. Spectrophotometry works on the Beer Lambert law equation. In case of bacteria because they are insoluble it gives density of the suspension.
Q - If most of the bacteria are transparent than how we are able to measure OD of a given sample in spectrophotometer ?
ReplyDeleteAns - As most of the bacteria are colorless , the bacterial cell density we are measuring its light gets scattered (absorbance not occurred ). Because most bacteria are transparent , the amount of light they absorb is negligible and most of the reduction in transmitted light is due to light scattering by the cells. Its scattering also depends upon microbial density ,more the density ; more the light will scattered . So the OD we get is the OD of scattering not the OD of absorbance in spectrophotometer.
Q- If beer-lambert's law is applicable for soluble particle so how we are able to measure microbial turbidity in spectrophotometer ? [As microbes are insoluble ]
ReplyDeleteLambert beer law is only applicable for soluble particle and as we know that microbes are insoluble but microbes gives density of suspension. That's why we are able to calculate OD in spectrophotometer .
Q) Can spectrophotometer be used to determine the concentration of “colourless” solutes such as E. coli?
ReplyDeleteSpectrophotometer is an instrument which measures absorbance at various wavelengths. The working principle of Spectrophotometer is based on Beer-Lambert’s Law.
The Beer-Lambert’s Law states that the amount of light absorbed by a coloured solution is directly proportional to the concentration of the solute in the solution and the thickness of the solution under analysis.
In case of coloured solutions, when light reaches the cuvette, some part of light is reflected, some part of light is absorbed and the rest of the light is transmitted and detected by the photoelectric cell.
But, in the case of colourless bacteria such as E. coli the absorption is marginal. However, the light is scattered by the bacterial cells in the solution due to which scattered light does not reach the photoelectric cell which eventually weakens the electric signal.
Roll no.-21MMB041
ReplyDeleteName -Milan Gajera
Q. The beer Lambert law is applicable for only soluble particle but bacteria is insoluble so how it can be used for Microorganisms &how measure OD for Microorgani?
Cell suspensions are turbid. Cells absorb and scatter the light. The higher the cell concentration, the higher the turbidity. Spectrophotometerscan measure intensity of light very accurately. The cell culture is placed in a transparent cuvette and the absorption is measured relative to medium alone. Optical density (OD) is directly proportional to the biomass in the cell suspension in a given range that is specific to the cell type. Using spectrophotometry for measuring the turbidity of cultures is known as turbidometry.
This has made spectrophotometry the methods of choice for measurements of bacterial growth and related applications. Spectrophotometry's drawback is its inability to provide an absolute count or distinguish between living and dead cell.
Q:-most of the bacteria are colourless so how we are able to measure OD of a given sample in spectrophotometer ?
ReplyDeleteOD is measured in a spectrophotometer. The principle is that most of the light scattered by the cells no longer reaches the photoelectric cell, so that the electric signal is weaker than with a cell-free cuvette.The OD of the culture is not an absorption primarily ( in case of dissolved dye) . Cells of many bacteria are colourless & real light absorption is marginal so the most appropriate term would be turbidity . The photoelectric cell doesnot know what causes the decrease in light intensity its only notices less light which is displayed as a number ( extinction value usually)
Q -How we get OD of decline phase as in decline phase bacteria are undergo lyses or death ?
ReplyDeleteAns - In decline phase microbial cell undergo cell death .But we still get low OD .By two hypothesis we can explain this :-
1 - Cell undergo death which leads to autolysis . Autolysis is the enzymatic digestion of cells by the action of its own enzymes, and it mostly occurs in dying or dead cells.The leak cellular content of lysed cell released out in medium which is utilised by unlysed cells.
2- Cells which get survive undergoes dormant stage,in which cell is viable but non culturable
Therefore we get OD because of autolysis and dormant stage of cell . so when light passes through unlysed cells and dormant stage cells we get OD . Also the rate of decline is more than the rate of growth in decline phase. so OD which we get is low .
Jayvi patel (21mmb019)
ReplyDeleteQuestion :when the cell number increase, OD also increase but when cell enter into death phase, no of cell remain same then what is reason of decrease in OD?
Ans:In log phase, cell number increase so the amount of light scattered and transmitted by cell also increase that's why OD increase but when cell enter into death phase, it burst and release it's cellular content in the suspension and get settled due to gravity force.OD is given by suspended cell in solution. Settled cell can not give it.due to this reason, light scattered by cell also decrease. That's why cell number remain same but OD decrease in death phase.
Roll no.-21MMB041
ReplyDeleteNAME-MILAN GAJERA
Q. Why does the O.D. decrease when the bacteria enters the death phase?
The conversion factor from OD to cell number or cell mass concentration drops after death because cell membrane is damaged and cytoplasm leaks out, as a result refractive index decreases and therefore OD drops because of smaller scattering of light.
IF we are not able to cultivate some of the Extremophiles in laboratory then how we can do research on them or do study about them?
ReplyDeleteResearchers have invented methods to study microbes that thrive in the world’s most inhospitable environments.
Microbes cling to life in some of Earth’s most extreme environments, from toxic hot springs to high-altitude deserts. These ‘extremophiles’ include organisms that can survive near-boiling heat or near-freezing cold, high pressure or high salt, as well as environments steeped in acids, alkalis, metals or radioactivity.
In 2014, Scott Tighe, a microbiologist at the University of Vermont in Burlington, gathered international collaborators for an ongoing initiative known as the Extreme Microbiome Project (XMP). The researchers hope to find genes that might indicate how extremophiles survive and whether they might make compounds that could work as antibiotics.
In their search for new microbes to analyse, the scientists have travelled to extreme locales, including the toxic hot springs of Ethiopia’s Danakil Depression, which are loaded with salt, acids and heavy metals, and a flaming gas crater in Turkmenistan.
But their main challenges arose back in the lab: “Massive hurdles, actually,” says Tighe. Microbes tough enough to withstand extreme conditions resisted scientists’ attempts to break them open and recover their DNA. So Tighe and the XMP team developed a six-enzyme cocktail — now commercially available as MetaPolyzyme — to break down any cell surface they might come across, adding detergents and organic solvents to collect nucleic acid on magnetic beads1. “It got to be a fairly exotic DNA-extraction technique,” says Tighe. Thus armed, the researchers are working through a freezer full of samples, says Tighe.
DiRuggiero has also worked with anaerobic hyperthermophiles, which grow at high heat and in the absence of oxygen. To culture them, she used heat-resistant, NASA-made culture jars in an incubator set to 95 °C — so toasty, the team jokingly called it the “pizza oven”. Standard agar in plastic Petri dishes would melt, so scientists turn to glass dishes packed with a gellan-gum derivative called Gelrite, which can withstand the heat.
Buzz Baum, a cell biologist at the Medical Research Council Laboratory for Molecular Biology in Cambridge, UK, is interested in cell division in the thermophile and acidophile Sulfolobus acidocaldarius. But live cultures cool as quickly as a cup of tea on the microscope stage, says Baum, and the microbes go into suspended animation.
The team decided to borrow a technique used in polymerase chain reaction machines, to warm the cultures from the top as well as the bottom. They recruited a lab member’s father and brother, both aerospace engineers, to fabricate a chamber out of aircraft aluminium. The researchers have published diagrams for this ‘Sulfoscope’, but any double-heated chamber should do, says Baum. The system allows the team to investigate proteins that maintain symmetrical cell division.
(Reference: Nature.com)
Q: Why the study of extremophiles is important ?
ReplyDeleteAns: Extremophiles are organisms capable of living in an extreme environment. An extreme environment is one in which most organisms would not be able to live and therefore is described as uninhabitable to most organisms. It could be due to extremes in temperature, pressure, or salinity that would be detrimental to most living organisms. However, there are still certain organisms, such as extremophiles, that are able to survive and thrive in such conditions. Extremophiles are typically unicellular organisms belonging to the domain Archaea.
Its study is important due to following reasons-
1:physicochemical parameters defining life on Earth and may provide insight into how life on Earth originated. The postulations that extreme environmental conditions existed on primitive Earth and that life arose in hot environments have led to the theory that extremophiles are vestiges of primordial organisms and thus are models of ancient life.
2:Extremophiles are of biotechnological interest, as they produce extremozymes, defined as enzymes that are functional under extreme conditions. Extremozymes are useful in industrial production procedures and research applications because of their ability to remain active under the severe conditions (e.g., high temperature, pressure, and pH) typically employed in these processes.
3:Extremophiles are also of research importance in the field of astrobiology. Extremophiles that are active at cold temperatures are of particular interest in this field, as the majority of the bodies in the solar system are frozen. The discovery of microorganisms with unusual biochemical properties, such as the ability to use arsenic rather than phosphorus for their growth, are also of interest to astrobiology, since extraterrestrial environments may favour life-forms that use or are built from elements not typically found in life on Earth . Thus, understanding the limits of life on Earth provides scientists with information about the possible existence of extraterrestrial life and provides clues about where and how to search for life on other solar bodies.
Roll no.-21mmb041
ReplyDeleteName-Gajera Milan
Q.what is important of Extermophiles and why we study of Extermophiles?
-Extremophiles offer numerous advantages including (1) the absence of contaminants in open door cultures subjected to physicochemical pressure, (2) their potential adaptation to industrial environments such as presence of toxins, radioactive elements or extreme pH and consequently their potential use for the biocatalysis of effluents and (3) their ability to produce enzymes with biotechnological applications.
-The study of extremophiles provides an understanding of the physicochemical parameters defining life on Earth and may provide insight into how life on Earth originated. ... Extremophiles are also of research importance in the field of astrobiology.
(From-advances in botanical research-2012)
-
Name :Jayvi patel (21mmb019)
ReplyDeleteQue:How can we conduct reserch on extremophiles as we are unable to grow
them in vitro?
Ans:These versatile organisams called extremophiles are able to grow and survive in harsh condition.
1.For research,scientist attempts to break down cellwall and recover their dna so they developed 6 enzyme togather called cocktail commercially available as meta polyzyme to breakdown cell surface by adding detergents to collect nucleic acid.
2. scientist has worked with anerobic hyperthermophiles. To cultivate them, they used heat resistant culture jar that is able to withstand 95•c in incubator. At such temparature standard agar in petridish would melt so scientist wrapped petri dishes with gelarite which can tolerate high temparature.
3.some scientist also manipulate gene. For that they create gene they want to use and isolate relative plasmid and then insert this gene into plasmid and then transfer to extremophiles. Some extremophiles can take up this plasmid from surrounding by process called transformation.
4.They also use electroporation, a pulse of electricity that creat hole in cell's membrane.
5. They have also tried to determine methylation pattern on extremophiles 's genome. That's important because microorganisams Will often destroy nucleic acid that have wrong pattern as a protection from invaders. Scientist modify those methylation system in ecoli to make new dna match that of the host. So that's how scientist find various way to study and reserch about extremophiles
This comment has been removed by the author.
ReplyDeleteName:- Jinal Bhavsar
ReplyDeleteRollno:- 21MMB003
Question:- Which is better:- Hand Sanitizer or Regular Soap
Answer:- Hand sanitizer can disinfect it at least 60% alcohol but soap and water is the most effective way to remove all kinds of germs, dirt and chemicals as applying hand sanitizer may e easier but it don't eliminate everything even the ones with sufficient alcohol cannot remove all types of bacteria and viruses. Soap and water are more effective at removing such illness causing germs because soap molecules themselves are effective at destroying the surface membranes of some bacteria and viruses in addition the lathering of hands and scrubbing thoroughly creates friction that helps in cleaning dirt away.
Hand sanitizer will work well in case where hands are not heavily soiled or greasy but in work where people handle equipment , food or play sports-sanitizer can't clean thoroughly enough.
Moreover it is ineffective if too little is applied or wiped off before it has dried completely.
Question:- Is Escherichia coli a Good bacteria or Bad bacteria?
ReplyDeleteAnswer:- Escherichia coli occurs naturally in the intestine of human being and animals.
Most Escherichia coli are harmless and actually are an important part of healthy human intestinal tract, it prevents the uncontrolled growth of harmful bacteria in large intestine. However some E.coli strains are pathogenic, which can cause illness either diarrhea or illness outside of the intestinal tract.
Question:- Escherichia coli divides every 20 minutes.The starting value is 1 bacterial cell. After 24 hours how many bacteria are present?
ReplyDeleteAnswer:- 24 hours = 24x60= 1440 minutes
1 generation- 20 minutes, (2^n = 2^= 20 minutes)
So according to that in 1440 minutes bacteria will divide 72 times (1440/20 = 72)
So number of generation is 72 then (2^n)
2^72= 4722366482869640000000. This will be total number of bacteria are present after 24 hours.
Question:- What if microbes disappears one day?
ReplyDeleteAnswer:- If all microbes will disappear the future of life on planet would be a world without bacteria and archaea. Then uncountable environmental impacts would be more acute. Also most biogeochemical cycling would be ceased.
Humans and animals waste would be accumulated in high amount, there would be very little decomposition,apart from inherent catabolic enzymatic activity. The essential role that microbes play in biomass recycling would not be served even by fungi and protist and it will result in a rapid depletion of nutrients from environment. As with bacteria and archaea free world and with humans and other animals would survive for sometime but long term survival of most eukaryotes may be not possible.
Question:- Can spectrometer be used to determine the concentration of colourless solutes such as Escherichia coli ?
ReplyDeleteAnswer:- Spectrophotometry relies on the absorbance of light by the solution. It works by sending a beam of light through a cuvette filled with the solution, and, depending on how much light passes through, the spectrophotometer can measure the amount of light/photons that was/were absorbed. If the solution is colorless, it absorbs no light so, in the case of colourless bacteria such as Eschierchia coli the absorption is marginal. However, the light is scattered by the bacterial cells in the solution due to which scattered light does not reach the photoelectric cell which eventually weakens the electric signal.
Question:- What is the maximum bacterial cell density that can be achieved in 1ml broth?
ReplyDeleteAnswer:- It will depends on type of broth we are using and also type of bacteria we are working with. Theoretically we can fit 10e12 cells maximum assuming no water and maximal packing density.
ReplyDeleteExtremophiles can survive in boiling water, freezing cold environments, high salt, high pressure, etc. Scientists are curious to explore the world of extremophiles. Identifying, culturing and observing extremophiles is a quite tedious process. However, scientists have found certain methods to observe them in laboratories. First, they had tried to find and manipulate the genes that help extremophiles live in extreme conditions. But to find those genes, they need to extract DNA from the extremophiles, and it is really difficult to recover DNA from them as they can withstand extreme conditions, so it is tedious to break extremophiles to recover DNA. Although, an enzyme cocktail has been developed, which break down any cell surface it comes in contact with. Different extremophile needs different conditions. For instance, halophiles grow under high salt conditions, so salt is added to the culture media. In the case of thermophiles, the microbes need high temperatures, and the major problem that scientists face during growing thermophiles is that the Petri plate melts at a temperature that is optimum for extremophiles. To solve this problem, NASA had developed jars that can handle 95 degrees temperature. Likewise, different techniques have been developed to grow extremophiles in the laboratory.
Q.- why large no.of microorganisms mainly found in large intestine??
ReplyDeleteRecent research on obesity, in mice and humans, has demonstrated that microbes of the intestine can have an important influence on host energy balance.
Human gut microbes perform many metabolic functions that our own bodies cannot carry out, creating a symbiotic relationship. For example, we consume plant polysaccharides that are rich in xylan-, pectin- and arabinose-containing carbohydrate structures, which we are unable to digest. Encoded in the genomes of gut microbiota, however, are a large number of glycoside hydrolases, which break down these plant products and convert them into usable energy sources
(From-https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4411945/)
Why 70% alcohol is used for disinfection ?
ReplyDelete70% alcohol is ideal for more powerful solutions. Pure alcohol coagulates proteins when in contact. Suppose pure alcohol is poured into a unicellular organism. Alcohol penetrates the cell wall of living organisms in all directions and directly coagulates proteins in the cell wall. A ring of coagulated protein prevents alcohol from penetrating extracellularly and prevents coagulation. At this point, the cell is inactive, but not dead. Under favorable conditions, the cells then begin to function. When 70% alcohol is poured into a unicellular organism, the diluted alcohol also coagulates the protein, but slowly and completely penetrates the cell before coagulation blocks. After that, the whole cell coagulates and the organism dies.
21MMB003
ReplyDeleteWhy 70% alcohol is used for disinfection and not absolute alcohol?
Isopropyl alcohol is fast antibacterial against bacteria, fungi, and viruses, especially in solutions containing 60 percent to 90 percent alcohol and 10 to 40 percent filtered water. When alcohol concentrations fall below 50%, their disinfectant properties rapidly deteriorate. Notably, increased alcohol concentrations do not result in better bactericidal, virucidal, or fungicidal effects.
When using isopropyl alcohol to kill or stop harmful bacteria, the presence of water is critical. Water is a catalyst that aids in the denaturation of the proteins in vegetative cell membranes. 70% IPA solutions penetrate the cell wall more thoroughly, allowing all proteins to coagulate and the microbe to perish. Evaporation is slowed by the presence of extra water, which increases surface contact duration and effectiveness. Overdoses with isopropyl alcohol.