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I'm Dan Buckley I study microbes let's answer your questions from the internet this is microbiology [Music] support So at culture pulp asks wait are there actual brain aiding amibas yes yes there are the good news is that only a few people every year in North America end up running into one of these organisms and if they do uh there's not a lot of Hope For You many of these cases are lethal for example there can be in in Texas or sometimes in Mexico the way that this happens might be if
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you jump off a rock face into really warm water and the water just goes right up your nose if it has one of these amoeba an amoeba called Nigeria feriz might be able to get access to your brain it's not designed to eat your brain but if it finds itself up there it's going to start eating and growing and dividing and dividing and dividing until you have millions and millions and millions of braining amibas up there at B1 asks does the smell of farts tell you
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a lot about the microbiome of the gut I assume a lot of it is driven by what we eat farts are 100% microbial the microbes in your gut are helping you to digest your food and when they break that down they break it down into nutrients you can also get volatile fatty acids so volatile fatty acids are small molecules like proprionate acetate and berate so when you smell poop what you're really probably smelling is butyrate normally if your gut is functioning properly these volatile
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fatty acids are being absorbed by your cells because they're source of energy that's where you get a lot of the energy from these microbes in your gut but if you've got an imbalance in that system because you ate something bad then some of these volatile fatty acids are going to come out with those farts and that's when things are going to start to stink so if you ever smell garbage that's been sitting out on the street for a few days you'll start to get these volatile fatty
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acid smells you can also get methane out of your gut so about a third of human beings have methanogens methanogens use hydrogen and CO2 and they turn it into methane the these people as well as people who make a lot of hydrogen or maybe the people who are able to light their farts on fire if you've ever seen that you'll also smell sulfur if you eat a lot of protein that protein is going to have some sulfur in it and the bacteria in your gut when they break down that they can make a gas called
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hydrogen sulfide and hydrogen sulfide smells like rotten eggs so yeah the smells you're getting are controlled by what you eat but very much it's the microbes that make 100% of those smells at gothan Fox asks do microbes dance if so how many could dance on the head of a pen the head of a pin is pretty pointy maybe two microns give or take but a bacterium is typically about the size of two microns so if we were to zoom way in we would see that it would have just
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about enough room for maybe one microb maybe two microbes at Ed Wilson asks if the number of microbial cells in a body is of the same order as that of human cells how much of my weight is microbes add up all the cells in in your body and then add up all of the microbial cells in your body we find that they're actually about the same microbial cells bacteria in particular are about a thousand times smaller than human cells so if we add up all of the mass of the
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bacterial cells you're going to find that that's 2 to 6 lb so a couple of kilogram and that'll change throughout the day right because when you go to the bathroom when you poop that poop is basically solid microbes except for maybe the the Stray corn kernel or a little bit of lettuce you've just lost a couple of pounds of microbes but don't worry they're going to grow back at Rover suede what is the fastest bacteria like if I were to stay a little race under a microscope who would win the
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fastest bacteria is delrio bacteria voran literally that translates into the wiggly leech that eats bacteria it real speed is about maybe 150 microns per second which is blazingly fast for a microbe if we were to shrink ourselves down to the size of this microbe it would be about 600 M hour right that's like the speed of a rocket car so you find them in freshwater habitats typically it's a predator of bacteria so they need to be really fast cuz they're chasing down those bacteria to try and
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attached to them and kill them you almost can't see them because you're looking under the microscope and they sort of go because they're just that fast if you want to look at them under the microscope you have to add something really viscous that's going to try to slow them down at J Swiss CCE asks predatory bacteria that is real AF you are right there are tons of predatory bacteria so these are bacteria that eat other bacteria they come in a lot of different varieties there are
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mixus mixus hunt in a Wolfpack Behavior they talk to each other using molecules so they can zero in on prey and then they surround the prey and secrete enzymes that cause them to dissolve there can be epibiotic parasites and predators like Vampiro vibrio that latch onto the outside of a cell and suck its cytoplasm and one of the most terrifying is delrio so delrio lives in aquatic habitats usually fresh water where it tracks down its prey it will actually attach to the prey and then it will
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penetrate the cell wall and push itself inside of that cell where it will grow it will replicate several times to make maybe eight or 10 or as many as 12 cells inside of the guts of the the prey cell that it's attacking and then when it's done they explode out and they swarm out at Mitch Brown 43 my biology test was like how do most bacteria move a magic I didn't even need to read the rest of the answers bacteria move through a process called chemotaxis bacteria don't have
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eyes or ears like you or I so they don't know know where they're going and so they do what we call a biased random walk they keep sampling over time is it good is it better they definitely move towards food so they can sense if the food concentration is high and if it's bad or if it's getting worse they just like Shake themselves up swim off randomly in a New Direction and through this random series of runs and tumbles they actually are really effective at
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finding the right way to go and then how do they get there well there's lots of different ways that microbes move so many microbes have a flagella usually stiff and helical shaped it spins and propels them helps them wiggle but then when they want to run they turn those flugel in the right direction and they all sort of coil up with each other and that allows the bacteria to shoot forward some bacteria also move by what we call gliding they sort of drive themselves along the surface with these
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suction cups they're just one little cell out in the world and so they need to find conditions that are right for them temperature light nutrients salinity they sense all of these things and then try to use this bias Rand and walk to get where they need to go at New Start 2024 The Last of Us zombie infection is real fungi can devour insects from the inside out and experts say it's not too far fetched that a similar parasite could evolve to infect humans the clickers that you saw where
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the fungus infects people coming out of the person's head I wouldn't worry too much about that unless you're an insect the opio corps fungus infects many different kinds of insects gets into their brain and then causes these insects to move in such a way that promotes the distribution of the fungus so that more ants will become zombies but insects are cold-blooded they're very different from us and so I wouldn't think that this fungus is going to infect people if I was worried about a
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zombie infection for people I would really think about rabies rabies is transmitted by a bite if you're not vaccinated or treated quickly it basically gets to your brain it can make you maybe want to bite people so we kind of do have a zombie infection we just have really good vaccines for it right now that Sublime Carnage what microb scares you the most honestly following the newspaper it's it's Aven influenza there's been Aven influenza around for decades the reason it's a problem now is
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there is a pandemic among the birds it's all over North America there are farmers who are dealing with this right now their chickens are getting sick their turkeys are getting sick but it's a big problem for us too CU that AV influenza can make people sick 40 or more million people died in 1918 from the first flu pandemic but then flu became seasonal then we have this Aven flu if those two flu happen to infect one person those two strains of flu can recombine part
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Aven influenza and human influenza it's a little bit of both and neither 100% of either and that's completely new our bodies have not seen that before and so your prior vaccination won't matter this will be a new pandemic that will be very problematic at niku kzer asks I'm just shocked there's a bacteria that eats metal what Incarnation there are lots of bacteria that eat metal there are organisms that can eat Chrome they can eat uranium they can eat all sorts of
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metals they actually in a real sense breathe the metal it's a kind of respiration so all living things get energy by moving electrons from one place to another many of them will have something called nanowires really small wires so they conduct electricity and so the microbes can then move electrons through that wire either put those electrons down onto the surface or pull electrons off of the surface and when it comes to organisms like iron reducing bacteria they're actually taking those
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electrons through the wires and putting them down onto a metal metal and causing that metal to be reduced when we take electrons off of metal for example iron we are oxidizing it and oxidizing metal is rust and if you look at pipes in factories or in pipelines or in boats the pitting and the rusting of that metal is often catalyzed by microbes who are basically living off of that metal itself at CERN lxxl asks how can bacteria become resistant to antibiotics so anytime
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there's a new change in the environment the microbes are going to try to evolve in response to that so that they can be more successful when we discovered antibiotics we discovered those antibiotics because they were made by fungi and bacteria that live in soil those bacteria and fungi make antibiotics to kill each other they're fighting with each other all the time but then those organisms are going to evolve resistance and they've had hundreds of millions of years of these
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back and forth Waring with antibiotics and then antibiotic resistance genes so we've been using antibiotics since like the 1930s and the 1940s the first antibiotics came from from fungi a scientist by the name of Fleming discovered penicilium that makes penicillin which was one of our first antibiotics and there was also really important discovery of streptomycin by a scientist by the name of Selman Waxman who is a soil microbiologist much like myself so we've discovered the
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antibiotics woohoo right we can make antibiotics too just like bacteria do well the bacteria already have counter measures if those genes and those organisms come in contact with our pathogens those pathogens you know they go to the abster they're like hey do you have any antibio itic resistant genes that might be useful to me and if they're useful horizontal Gene transfer gives you a conduit to get those genes Evolution does the rest right now we have antibiotic resistant pathogens
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antibiotic resistance in general is is a real serious problem and the way to fight it is to try and figure out how these organisms are evolving and try and use our antibiotics in a way that slows down that pace of evolution so that the antibiotics are more effective for for longer time ATS thfc asks can bacteria survive high temperatures in microwave radiation do we really need to clean out our microwaves the reason you want to clean your microwave is because all that
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food just gets nasty in there it's not because there are organisms that are evolving to be resistant to that radiation the microbes in your microwave are going to be mostly like the ones we see on our sponge right they're going to be staus they're going to be basilis maybe some pseudomonas so probably they're going to end up dying in your microwave microbes themselves can survive really high temperatures I think the record microbe can survive temperatures at 250° F and we definitely
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have microbes that can survive high radiation so there's an organism by the name of dinus radiodurans the terrible radiation resistant ball this organism is able to withstand 5,000 Grays of radiation people would be dead after maybe five Grays of radiation so dakus is one of the most radiation resistant organisms on the planet in fact NASA has done experiments they found that dinus can live for years in space many of these organisms that live in these unusual environments we refer to them as
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extremophiles at IO Silver Lining asks oh dear God what are extremophiles we use this term extremophile to refer to microbes that thrive under conditions that would be pretty much lethal for most other organisms we have thermophiles which like really high temperatures like pyrococcus furiosus the Furious flaming Fireball pyus furiosus can live at temperatures above the boiling point of water in fact it thrives in those conditions at the bottom of the ocean there's really high
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pressure that really high pressure changes the boiling point of water and so we can have organisms like pyrococcus living at volcanic seeps at the bottom of the ocean we also have acidophiles there are organisms that live in acid mine drainage so this is like the runoff from a mining operation where the pH is 0.5 that's pure sulfuric acid you can almost watch a nail rust under these conditions but this is home for these guys if there's liquid water probably you have a microbe there and probably
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they've been living happily there for millions of years ATS Chun asks us I'm doing microbiology and I genuinely don't know the difference between bacteria fungi and viruses what a joke microorganisms in general are just anything smaller than what you can see we have some that are called cells cells have a membrane they have a cytoplasm we have one kind called a pro carot which is an organism that has no nucleus it came first they evolved 4 billion years ago and they split into two groups
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bacteria and ARA eukariotic cells evolved much later ukaria have a nucleus and many of the ukar iotic cells are single- celled organisms but they evolved into dogs and cats and plants and all the macroorganisms that we see today then there's fungi ucareo organisms maybe they live in soil maybe they look a little bit like this guy and then the bacteria would look a little bit more like this a little bit more slimy a lot less fuzzy you have cells viruses and that's most of your
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microbial World space siai step asks I just learned like 10 seconds ago that there are magnetic bacteria there are magnetic bacteria magnetic bacteria have little magnets that are inside of their cytoplas that help the bacteria line themselves up with magnetic fields they use that like a compass that helps them change directions why would a bacterium need a magnet we live on a a sphere right the magnetic pole is not directly north it's actually directed a little
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bit down so if I were to point straight towards the magnetic north it would be in that direction and so bacteria know this right so when they're swimming North they're actually swimming down and so these bacteria live in sediments usually where you have water overlaying sand or something like that there's oxygen up here and there's no Oxygen down there by swimming North to go down and South to go up they can position themselves in the right position with respect to oxygen and in fact it was a
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group in Europe they invented a a micromanipulator that controlled some magnets and they attached it to an old Nintendo video game controller and get the microbes to sort of swim around and do whatever dance they wanted they actually put it to music you could look it up on YouTube Ashley Maria asks ever wonder what kind of germs are on the subway poles you hold microbes need water to live so wherever you have water you're probably going to have a lot of microbes the subway pole it's dry
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there's actually pretty few microbes on there but if we did find microbes in there it's probably from one or two sources right the one source is us our skin constantly sloughs off and because our skin is covered with microbes when we Slough off that skin the microbes come off too and so anytime you're in uh an indoor environment the dominant microbes are going to be those microbes associated with skin one of our more common organisms is stacus this is a scanning electron microscopic image of
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some bacteria that someone Grew From a surface not dissimilar from your Subway pole these little balls of grapes these are stafl cacus orus which is one of the most common organisms on our skin it's called orius because it makes a gold color when it grows on a petri plate most of the staff that you're going to encounter is not dangerous but there are some staff that have antibiotic resistance genes that have toxin genes that can cause uh pretty bad infection
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so if you get an infection in a hospital it's probably from a multi-drug resistant staff orius or methylin resistant staff orus probably the organism on your pole in the subway is not methylin resistant staff orus but once we move outside one of the things that would grow most vigorously and we see most common is an organism called basilis such as basilis suus or maybe billus megaterium basilis serus this sort of wrinkly organism you're looking at right here they live in soil but
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because they make spores they can survive a long time at Haley 3 p says I love tardigrades how do they survive LMAO well tardigrades are kind of crazy they are microorganisms they are eukaryotic so they're made of cells that have a nuclei they're multicellular which is different from a lot of the microorganisms we've been talking about here this is a very unusual and unique shape it's not something we see a lot of in the microbial World they are able to survive really harsh conditions by
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allowing themselves to be completely desicated the key too is that when you rehydrate them so you had to drop water to this guy you know boom he's ready to go at ho Adventures asks why does cat poop have to be bad for pregnant people all I want is a cat RN cat poop can carry the cysts of Toxoplasma Toxoplasma is a parasite it's not usually harmful to people but it can cross the placenta and infect embryos and infect fetuses and it is a cause of miscarriage and so
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if you're pregnant you definitely want to avoid the cat poop Toxoplasma is actually a really interesting organism here we're seeing a Toxoplasma next to a red blood cells it Cycles between different animals so it's often found infecting mice this parasite Toxoplasma affects the mouse's brain and makes it more likely that that Mouse is going to get himself killed by a cat that actually helps the parasite because when the cat eats him it ends up in the poop of the cat so this is a way for these
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cysts to get spread wider and wider at ho Adventures if you really wanted to have a cat have an indoor cat indoor cats are less likely to be exposed to Toxoplasma or if you had somebody else in your household clean the litter at General Katana wants to know but do amibas no amibas don't amibas are asexual they divide by binary fision that they split into two cells amoeba are in a group of organisms called protests so protests have evolved many different ways of of doing sex and
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protest can also engage in something that bacteria do which is called horizontal Gene transfer which is where maybe you move individual pieces of DNA back and forth as well at Mech Larder asks how the duck does horizontal Gene transfer work in viruses we use the term horizontal to contrast from vertical and vertical transfer this is like a family tree you have your great-grandparents then your grandparents then your parents then you horizontally is like taking DNA
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from you and and sending it to somebody you've never met before that's something that microbes do all the time and it's super important for their evolution so for viruses this is kind of tricky cuz viruses are not cells viruses are basically just a chunk of nucleic acid with a little bit of protein around it so how do they exchange information well they do it when they're in a cell and while they're inside of a cell they're making copies lots of little baby viruses when they're doing this they
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could pick up a piece of DNA from the bacterial genome and then when they package a new baby virus and it goes out into the world it's picked up that DNA so the virus wins by giving these genes to the cells which then make those cells more effective pathogens and so this horizontal transfer is just super important for the evolution of microorganisms we have a question from at Seda anoas 2 what's the largest bacteria found so far the largest bacteria currently is tho Margarita
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magnifica 2 cm long and about 50 microns in diameter so this is almost the size of a human hair so it's something you could see with your eyes it was only discovered about 2 years ago living in the mangroves people saw these sort of fuzzy things and thought what could that possibly be but looked at it on the microscope and found out hey this is actually a bacterium at SRA asks did you know the little creatures in your gut control your Cravings they themselves
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want the sugar Etc processed foods the Cravings stop after a while because the microbiome that was eating the garbage dies out this is actually plausible microbes in your gut are playing a really important role they're helping you to break down your food in fact pretty much all the plant material you eat you would be unable to digest those without the bacteria in your large intestine they break it down into materials that are nutrients for us but they also make other chemicals too some
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of these chemicals can cross into your blood some of these molecules are very similar to hormon hormes that can control how we feel so how hungry we are or how full we feel or maybe our moods there have been experiments in mice that have provided evidence to support that changes in your gut composition could affect your behaviors hard to do these experiments with people but certainly this is plausible Ruth vmd asks how about feal transplant for improved microbiome we take antibiotics all the
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time to treat infections but these antibiotics you know they kill microbes so they're going to kill a lot of the microbes in your gut and if you take antibiotics often you'll find that you'll end up with diarrhea usually this just resolves itself your microbes will grow back but sometimes there can be an organism called Clum defil and you can think of this as like a weed it's an organism that if it's too abundant it becomes a problem often SE diff as we call it is resistant to antibiotics and
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so when you take those antibiotics they kill off your Healthy microbes and CF doesn't get killed off and because it's like a weed it can grow and take over you could die from a SE diff infection and so the best treatment right now for this kind of infection is a feal transplant you'd get a donor usually that's going to be a member of your family and you'd make the nastiest milkshake ever put this stuff in a blender you'd mix it up into a slurry you'd put it into a tube and then the
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tube goes where the sun don't shine you can reintroduce sorry for that the healthy kind of organisms and once you have your Healthy microbiome back it will suppress this disease and cure it at lemi OTW so what do microbiologists do when there isn't a Pand mic endangering lives there's a lot to do microbes are the most diverse organisms on the planet only about maybe 10,000 or 20,000 of them have been described most of them have yet to be discovered they've yet to be named and when we're
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not doing that we're also trying to predict the next pandemic so if you would have asked a microbiologist 20 years ago what are the most dangerous scary microbes out there Corona virus even 20 years ago would have made the top five and that's because we know that a lot of viruses from bats can jump over and infect people and so so when this pandemic started we were really poised to move quickly the fact that we were able to get a vaccine in a year is an indication of how much work
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microbiologists were doing in the off seon at lubos kulok asks NASA's perseverance Rover just found something Wild on Mars not saying it's aliens but this rock has features super similar to what microbes would leave behind if Mars was teeming with life billions of years ago what do you think I think it's likely that there might have been Life on Mars the rocks that NASA just found on Mars Mars have a couple of really interesting characteristics number one they're sedimentary rocks so they're
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rocks that were formed underwater and we know that water is really important for Life the other thing that's really important about these rocks is they have evidence of organic molecules molecules typically associated with living things they can be food for cells but also the cells when they die their little dead bodies make organic molecules but those rocks if they can bring them back to Earth we would be able to determine whether or not those Organics are bio
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signatures or EV of life so the real imitation on Mars is that it's very dry right now but in the past it's been wet so the question was did microbes live in the past if they still live the question would be are they living probably underground at Nile FM asks you'll find more germs and bacteria on a tablet or mobile phone screen than on a toilet seat is this true or false that would actually be true if we were to look at both of these surfaces they're very dry
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and they're also often wiped down and they're very smooth and so as a consequence there's not not going to be a whole lot of bacteria on either one of them if you do want to look for bacteria you can look right there so keyboards have a lot of bacteria and the reason for that is they collect dust right there's lots of space in between those keys one of the places you're going to find the most gnarly stuff is your kitchen sponge or your wash rag and that's because it's often wet it's often
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getting a lot of food right there's a lot of surface area cuz it's porous so the microbes can live survive and grow in that and so you definitely want to let that thing dry out and you want to wash it frequently if you have a fish tank that is full of microbes particularly that filter in the back that's like a rainforest living in that thing at Water Wolf 4 asks did you know there are more beneficial microbes in 10 square meters of healthy soil than all other animal and plant species on the
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planet # organic just to give you an idea about how complicated the soil microbial Community is we could look at say a 10 m Square section of soil 10 cm deep because that's where the best soil is going to be we'd have about 12 million G of soil in that patch we have about 1 * 109 bacteria per gram of soil that's a billion bacteria per gram we multiply those we have 1.2 * 10 the 16 bacteria just in that outdoor backyard patch if we line those guys up end to end 10 to the 16th bacteria each one is
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about 1 Micron long we would find we have about 10 billion with a be meters of bacteria enough to get to the moon and Beyond about 30 times of bacteria lined up end to end live living in that 10 squ met patch of soil so our next question is from at Marlene MZ how do microbiologists leave their house after knowing what they know one thing you learn when you're a microbiologist is Everything You Touch everything you eat everything you drink is full of microbes
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if we had people coming to this planet they could be mistaken for thinking that the dominant form of life is microbial because most cells on this planet are microbes and the secret is most microbes don't hurt you one of the really important jobs that microbes do is to make the oxygen in the air that we breathe 30% of our oxygen is coming from Plants but most of it comes from microbes billions of years ago there's no Oxygen hydrogen sulfide toxic gases uninhabitable Planet but once the
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cyanobacteria show up they turn it into a world that we can live on we couldn't live on this Earth without the microbes doing their job for us at Daniel sprockett calling all hashtag microb tweeps what do you think is the most important or interesting unanswered question in # microbiology the vast majority of microbes out there in the world the super Mass majority we don't know anything about them it's very difficult to identify these microbes under the microscope most of the
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microbes when we put them on a petri plate they just don't grow So within the last 10 or 15 years we've developed genomic Technologies like metagenomics when we sequence all of the DNA from a particular sample and so if we have something like soil it has thousands tens of thousands of different species they all have genomes so there's millions of genes we can can sequence all of their DNA like a great big jigsaw puzzle and when we do that we see that the vast majority of these species don't
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match anything that we've described microbiologists call this microbial dark matter when we think about dark matter in terms of astronomy we think about this material that sort of pulls the shape of the universe together which you can't really see in a telescope we don't know what it is but it's out there well it's the same with microv at Evan Pro asks can microbiologists identify common bacteria by smell like can they smell at or a dumpster or wilted broccoli and say
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ah good old Clum prefer engin or do bacteria mostly smell the same we can identify a lot of smells they're associated with certain organisms or processes for example there are organisms called pomonis if you smell them lift the plate up and do one of these if you got the smell of grape jelly that might give you a clue that that's a Pamona so many pseudomonas smell like grapes there's an organism I study called streptomyces streptomyces live in soil if you've ever gone outside
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after the rain and you smell that earthy goodness right that's actually the odor made by these streptomyces so they make a compound called geosman and that's what you're smelling when you smell the rain hit the soil so those are all the questions for today thanks for watching microbiology support
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