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The strange, beautiful and powerful world of microbes RAVINDER NAGPAL1, A.K. PUNIYA1, M. PUNIYA2, ARTI BHARDWAJ3, KISHAN SINGH1 AND HARIOM YADAV4 1Dairy Microbiology, 2Dairy Cattle Nutrition, 4Animal Biochemistry, National Dairy Research Institute, Karnal 132001, (Haryana); 3CAEHS, Meerut (UP), India. The first MICROBIOLOGIST and his MICROSCOPE Anton van Leeuwenhoek - A classical example of serendipity. By wanting better magnifying lens with which to judge the quality of the cloth he was buying Leeuwenhoek discovered bacteria What Microbiologists Do ??? • Work in almost every industry - from food, agriculture and pollution control to biotechnology, pharmaceuticals and health, government agencies and labs, in education as teachers and researchers. • No one microbiologist can study everything! That's why people who become microbiologists usually focus on a particular microbe or research area. – Bacteriologists focus on bacteria. – Virologists specialize in viruses. – Mycologists study fungi. – Epidemiologists track down outbreaks of disease – Immunologists study how the body defends itself against microbial invaders? What is a microorganism? • An organism that is too small to be seen clearly with the naked eye. • Generally single cells, but some exist as cell clusters; often work as a community Where do microbes fit in the biological world? Microbila cell: Efficiency in deficiency „Most of the vital organs of eukaryotes are missing‟ The power of microbe lies in its speedy growth Imagine the weight of biomass of E.coli after 24 hrs under optimal growth? Never underestimate the power of a Microorganism. • Microorganisms, just like God cannot be seen through naked eye but we can feel their impact on us in various ways. • Though only 3% of the total microbial population are harmful to the humans. • Without knowing, we are getting their help from the historic days eg. souring of milk (dahi), pickels, jams, dosa and idly making, wine production etc. “Microbes are always at Work” Mind it… contd… •The pressure inside a bacterial cell is about 2 atmospheres, which is roughly the same as the pressure in a car's tyre. •A human can be killed by exposure to less than 500 rad radiation. However, Deinococcus radiodurans is a bacterium, which can survive exposure to upto 3000000 rad of ionizing radiation. •'Botulin„, a toxin produced by Clostridium botulinum, is highly toxic and if everyone has to be killed on this earth, less than 1kg of this toxin will do. Bacterium: as big as the head of a fruitfly and can even "hold its breath"? • A giant bacterium, Thiomargarita "sulfur pearl of Namibia,“. • The bacteria (3/4 mm wide) about 100 times larger than the largest known, Epulopiscum fishelsoni. • Thiomargarita namibiensis lives on the nitrogen and sulfide on the ocean floor produced by rotting plankton and algae. • Nitrate however is not steadily available, so they "hold their breath" while they wait for something to stir up off the ocean floor. • They do this by storing sulfur just under their cell wall, and keeping nitrate in a big sac. This could be one of the reasons why the bacterium is so big. A Humongous Fungus • Did you ever wonder what the world's largest organism is? • Maybe you'd pick an elephant or a giant whale. • Well, those choices would be wrong; this organism is actually a soil Fungus, Armillaria bulbosa, found in a northern Michigan hardwood forest. • It is most likely one of the world's oldest organisms as well, exceeding 1,500 years and weighing over 100 tons. • It is actually a plant pathogen, whose hyphae pierce the roots of aspen trees and absorb nutrients from them. Therefore, the majority of the fungus is underground and only tiny edible „honey mushrooms‟. Facts About Microbes • Microbes outnumber all other species and make up most living matter (~60% of the earths biomass). • Less than 0.5% of the estimated 2 to 3 billion microbial species have been identified. • Microbial cycling of critical chemical elements such as carbon and nitrogen helps keep the world inhabitable for all life forms. Contd… • Microbes generate at least half the oxygen we breathe. • Microbes are roots of life's family tree. An understanding of their genomes will help us understand how more complex genomes developed. • Microbial genomes are modest in size and relatively easy to study (usually no more than 10 million DNA bases, compared with some 3 billion in the human and mouse genomes). • Microbial communities are excellent models for understanding biological interactions and evolution. Strange Facts and Bacterial Records!!! (Omnipresent). Everything is everywhere, the environment selects - Beijerinck M.W. Microbes thrive in an amazing diversity of habitats in extremes of heat, cold, radiation, pressure, salinity, acidity, and darkness, and often where no other life forms could exist. Contd… • Underground: Chemolithotrophs found in Basalt deposits 1500m (4700 ft) underground in solid rock. • The Sky: Some bacteria spend their whole lives in the atmosphere, growing and reproducing in the clouds above our heads. • On Ice: Some bacterial species live in the ice of glaciers and others have often found in the snows of the North and South poles at -17 and -85°C. Contd… • Not So Cool: Some bacteria have learned to live in hot springs. Some species are happy at 75°C while others think even this is cool. Species of Aquifex can live in water as hot as 95°C. Archaea are happy to grow deep sea hydrothermal vents at 106°C • The Deep Sea: Bacteria „known as Extreme Barophiles‟ live at depths of >10000 m and are able to survive pressures in excess of 1000 times the air pressure at sea level; and they cannot function properly at pressures less than 400 atmospheres and may die in a couple of hours if brought to the surface. Life in the extremes Sahara desert Life in the extremes Yellowstone National park Life in the extremes Lake Magadi, Tansania Life in the extremes Yellowstone National Park Life in the extremes Life in the extremes Contd… • Fast Movers: Some bacteria can move by flagella that enable them to obtain speeds as high as 0.00017 km/ hr. This may not seem very fast, but remember that we are talking about very small organisms. They are travelling at about 50-60 body lengths/ sec which is equivalent to a 6 ft tall man running at 100 m/ sec, 9 times faster than the world record. Cheetahs, are the fastest animals on land but even they only move at about 25 body lengths/ sec. “What is soil, becomes grass, becomes a cow, becomes you and me and then becomes soil again. Without microbes, the whole ecosystem would collapse” Facts About Beneficial Bacteria • The opposite of antibiotics are probiotics - a term coined in 1965 to describe substances that favor the growth of beneficial microorganisms in the body. • Two species of probiotics, Bifidobacterium and Lactobacillus, have been studied the most. • Bacteria that produce the enzyme lactase help reduce lactose intolerance. Tell me what you eat, and I will tell you what you are - Brillat-Savarin Learn a lot from a microbe • Halobacterium, may hold the key to protect astronauts from one of the greatest threats they would face during a mission to Mars: space radiation. • The harsh radiation of interplanetary space can penetrate astronauts' bodies, damaging the DNA in their cells, which can cause cancer and other illnesses. • Halobacterium appears to be a master of the complex art of DNA repair. This mastery is what scientists want to learn from. Serratia has a religious history and can cause severe infections in humans? • Serratia marcescens, when grown in colonies, produces a bright red pigment similar to the appearance of blood. • In mediaeval churches priests would discover that bread left in moist places would "miraculously" produce this "blood", thus leading to the belief that the bread's red appearance was because it had been stabbed by unbelieving Jews. • In 1819 Bartolemeo Bizio, a pharmacist, discovered that the red pigment occurred because of bacteria. Martian microbes may exist ? • Life On Mars??? No one knows for sure yet! • But in August 1996, scientists announced that they had extracted what they believed to be fossils of an unknown bacillus shaped microorganism from inside a meteorite from Mars found in Antarctica.. • The meteorite left Mars 16 million years ago and landed in Antarctica 13 thousand years ago. • This may support the theory that life did or does still exist on Mars! Wow! Life on the Red Planet! We are not alone! Or are we? Shergotty, Bihar, India (1865) Mars - Climate and Life Postulated Mars-Biosphere Mars-Climate and Life Liquid water only in deep subsurface regions Life either extinct or in subsurface niches: Mars from Pathfinder Life on Europa? Moon of Jupiter Antarctica, 1984 Bacteria sometimes catch A Virus Bacteriophages – “bacteria-eaters”, viruses that use bacteria to multiply In the 1990s, bacteriophage research became an alternative for scientists worried about antibiotic resistance. Researchers in America followed the example of scientists in Western Europe who were treating patients with bacteriophages and obtaining great results. When antibiotics don't work for a bacterial infection, doctors can use bacteriophages to kill the bacteria. Although ironic, a virus can make us feel better! Microbes enables cows to eat grass? o Microbes living in the rumen of the cow are responsible for the breakdown of the carbohydrate cellulose of plants. o The cow lacks the enzymes to break down carbohydrates. o Without microbes and their enzymes, ruminants would not be able to derive any energy or nutrients from a diet of grass. Microbes have a built-in compass? • Aquatic, anaerobic bacteria called magnetotactic bacteria find their way around by using the attraction from the earth's magnetic field. • When placed near a magnet, they are attracted to the magnet's northern pole because the bacteria make magnetic particles which contain iron. • When lined-up, the particles make a long magnet that is used by the bacteria as a compass. • It is this built-in compass that enables the bacteria to find its way down to the deep, oxygen-free parts of its aquatic habitat. Diamonds are made from dead bacteria??? • Carbon, the main component of most diamonds, usually contains an isotope of light carbon (12C), which is utilized by some living organisms. • Therefore, eclogitic diamonds with large amounts of the isotope 12C, are believed to have an organic origin. • These were formed from carbon near hydrothermal vents which was also utilized by the bacterial communities near the vents. • Thus through time, heat and pressure were able to turn the carbon along with the bacterial colonies into diamonds. "So, those sparklers of yours may just be clumps of billion-year-old bacterial corpses" Microbial Jugnu: Bacteria that emit visible light? • Lightning bugs make light, but interestingly enough, bacteria produce light in basically the same process called bioluminescence. • „Luciferase‟ - uses molecular oxygen and a protein that has a particular vitamin FMNH2 attached to it. • „Luciferase‟ - causes oxidation reaction to occur between oxygen and vitamin leading to the conversion from FMNH2 to FMN. • As this occurs, luciferin emits visible light! • The color of light (orange, yellow, yellow-green, or blue-green ) depends on the kind of luciferase and amount of oxidation of the vitamin attached to the luciferin. Enzymes that bacteria use to break down dead, chilled whales may be used in cold-water detergents? • The cold temperature slows the rate of biological decay and in a whale, the oil-laden bones are the last things to be decomposed by bacteria at depth of 3300 feet. • The detergent industry's current fat-digesting enzymes are only effective in warm water, 105ºF. • Therefore, in cold water the enzymes do not gulp up oil or grease. Hence, a tremendous amount of energy savings could be obtained when using a cold-water enzyme that worked on stains. Microbes can degrade explosives? • Trinitrotoluene, TNT, is a problematic explosive that contaminates the soil in areas where ammunition is kept. • Bacteria named Clostridium bifermentans is able to break down this contaminant. • When provided with starch as energy source, the bacteria can break down the TNT through co- metabolism by broken-down TNT as a source of carbon. Bacteria can help clean up oil spills? • After the Exxon Valdez crashed off the shore of Alaska, spilling its contents all over the area, one of the biggest contributors to cleaning up the environment was Pseudomonas. • Scientists found that by feeding the contaminated area with oxygen and waste water, the bacteria present there were provided with the nutrients needed to flourish, thereby encouraging the break down of hydrocarbons within crude oil by Pseudomonas. • The hydrocarbon that the bacterium feasts on are converted to carbon dioxide and water. Microbes might be used to breakdown dirty laundry on long space flights? • One of the problems that would be encountered, which is now one of the problems with the Russian space station Mir, is the disposal of dirty laundry. • Presently, there are only two supply trips a year to Mir, so six months of stockpiling doesn't work too well. • Russian scientists are working on developing a mixture of bacteria that could be used to biodegrade dirty underwear. Bacteria keep vegetables fresher? • Even vegetables that are kept in airtight containers are prone to spoilage by E.coli and Listeria. • Lactic acid bacteria, are an alternative solution to this problem by producing natural acids that prevent Listeria from growing in foods. Bacteria are used to make chocolate? • Chocolate comes from the seeds of the Cacao tree. • The seeds come in pods and the only way to retrieve the seeds are to ferment them with yeasts and lactobacilli and Acetobacter. • The Lactobacillus secretes an acid to help break apart the pod. Microbes can make plastics ? • Alcaligenes eutrophus, is a useful bacterium having the capability of making plastics. • The bacterium is able to accomplish this feat because it has granules that are made of a fat-like polymer and not starch, like the granules of other bacteria. • These plastics can be readily degraded and hopefully will pose less environmental threat. • There are strong hopes of using these bacteria and their plastics for medical purposes. Microbes are all over your skin? • While bacteria are found on your fingers, toes, arms and legs they are far more numerous on your face. • They are found above and below the surface of your skin and are in no way harmful. • However, all teenagers have had at least one zit in their lifetime, are called: pimples, blackheads, whiteheads, blemishes, acne, etc. • And while bacteria are not the cause for zits they do inhabit those little imperfections. So, the next time you pop your pimple you must know that you are unleashing an army of microbes. Microbes cause body odor? • The sweat that comes out of your underarms actually does not smell bad. • The reason that people give off odors when they sweat in their underarms is that bacteria living there like to eat sweat, and as a result produce waste products that cause it to smell. • Body odor can be eliminated by using deoderant. • Deoderant kills the bacteria under your arms so that it cannot make your sweat stink. “So don't forget your deoderant; it does more than just mask body odor, it stops it before it happens!” Sick Building Syndrome? • Fumes from certain construction materials in buildings e.g. malls, are responsible for giving people severe headaches. • Microbes living in potted plants eliminate Sick Building Syndrome by degrading the fumes. • However, suffering people may be glad to know that helpful bacteria can solve their problem. Mycobacterium tuberculosis is the literary microbe? • Famous writers like Keats, Browning, Austen and Orwell have all suffered from tuberculosis and because of this the microbe has been called the literary microbe. • Tuberculosis is also considered to be the greatest killer of all times. About one hundred thousand million people have been affected. This bacterium is transmitted through air or infected milk. Microbes form fossils? • In 1950's-1960's, micropaleontologists discovered layers of sedimentary rocks, wavelike stromatolites in Great Lakes, are believed to contain microbial fossils. • Some fossils are 3.5 billion years old, meaning that they were formed only one billion years after the creation of the Earth indicating that microbes are the earliest forms of life on Earth. There's a "Sleeping Beauty" story for bacteria? • In May 1995, scientists were the prince as they revived 25-40 million year-old bacteria from the stomach of a bee that was preserved in tree sap. • It was this event that led to the notion of Spielberg's Jurassic Park, where dinosaurs were created after their DNA was extracted from mosquitoes trapped in tree sap the same way. “The dinosaurs, however, were the ones who took the limelight away from the bacteria on the movie screens” How Does Salmonella Get Inside Chicken Eggs? • The bacterium actually lives in the feces of chicken. • Because chickens sit on their eggs, even before they are collected for consumer purchases, the eggs may be subjected to the bacterium. • It was found that S. enteritidis could actually penetrate the hard outer shell of the egg and live inside the yolk, where it can reproduce. • The bacterium could infect hens' ovaries, and contaminate the egg before it even developed a shell. Infected rats make easy cat snacks • Toxoplasma gondii, a parasitic infection in rats, alters their natural behaviour and makes them easy prey for cats. • Toxoplasma gondii is found in about 35% of rats but prefers to live in cats. • It ensures its return to its favourite host by affecting the brains of the normally cautious rats, making them outgoing and active and an easy meal for a hungry cat. • Rats can usually detect subtle changes in their environment. It makes them very hard to trap or poison but this parasite overrides the innate response - they almost taunt the cats in a sense (remember Tom n Jerry ???). Caught Dirty-Handed!!! • When was the last time you washed your hands? • Did you use soap? • What have you done since you washed? • Have you eaten, put your fingers in your mouth or touched someone else? • There are millions of microbes on your hands. Most are naturally occurring and harmless. But some may be disease- causing germs. Hand washing with soap lifts off those microbes and rinses them away. • Observations in public restrooms reveals what????? Bacteria can help give your jeans the right ‘fade’ • Alkalothermophilic Thermomonospora produces enzyme cellulase, which when mixed with a coarse denim cloth reduces its hairiness and makes it softer and lighter. • It gives same appearance as a stone wash, causes no damage to drums of washing machines by preventing wear and tear of the material. • Finish can be controlled to desired level by controlling the amount of enzyme. Bacteria can act as insecticides? • The first major products of agricultural biotechnology was Bacillus thuringiensis, producing proteins that are toxic to many insects. • Now, scientists have spliced genes of it into crops, that produces toxins fatal to crop damaging pests, but harmless to "good" bugs. Thanks for your kind attention
"The strange_ beautiful and power"