Speaker 1: Hey, everybody, Welcome to Stuff to Blow Your Mind. My
Speaker 1: name is Robert Lamb and I'm Joe McCormick, and we're
Speaker 1: going into the vault. This is not a Saturday Vault episode.
Speaker 1: We're airing it in place of one of our regular
Speaker 1: Stuff to Blow Your Mind episodes this week, just to
Speaker 1: cover some time off. This episode originally aired on July nineteen,
Speaker 1: and it was called Electric microbe Land. This was suggested
Speaker 1: as a as a vault episode by a listener not
Speaker 1: too long ago. Yeah, so yeah again. Originally this one
Speaker 1: was a Summer of ten, but we're giving it to
Speaker 1: you again on the very last day of of So
Speaker 1: let's have a listen. Enjoy this regifting Welcome Stuff to
Speaker 1: Blow Your Mind, a production of I Heart Radios. How
Speaker 1: Stuff Works. Hey, welcome to Stuff to Blow Your Mind.
Speaker 1: My name is Robert Lamb and I'm Joe McCormick. Can
Speaker 1: we figured we'd start off today talking about our favorite
Speaker 1: electricity monsters. Robert, what's your favorite electricity monster? Oh? You know, my, my, my,
Speaker 1: just gut instinct answers to go with Blanca from Street Fighter.
Speaker 1: You know, he's the green skinned and I was, I was.
Speaker 1: I looked into this a little bit. I was never
Speaker 1: sure why he had green skin. Apparently some alleged backstory
Speaker 1: involving chlorophyll um, but I don't know. He ends up
Speaker 1: with he's like a beast creature, a beast man with
Speaker 1: green skin and like bright orange hair, wearing board shorts,
Speaker 1: wearing board shorts and just kind of doing this this,
Speaker 1: this kind of hulking uh pose bent over, and then
Speaker 1: he can produce electricity. Basically has the powers since he's
Speaker 1: kind kind of a you know, on amlogum of various
Speaker 1: Amazonian things. He has the powers of an electric eagle,
Speaker 1: and so he can shock his opponents that way. That's
Speaker 1: a good one. Uh. There there are a few really
Speaker 1: good electricity movies. By really good, I mean really bad
Speaker 1: from the nineteen eighties and nine indies. Did you ever
Speaker 1: see the Pulse? I don't think I ever did. I
Speaker 1: think there was another horror movie called Pulse, which was
Speaker 1: about something else. So this one was about. Uh It's
Speaker 1: like some family living in a house and like a
Speaker 1: regular suburban neighborhood in California in the nineteen eighties, and
Speaker 1: an evil burst of electricity goes throughout goes out through
Speaker 1: the mains. Uh. I don't remember if there's like an
Speaker 1: evil storm or like an alien arrives or something. But
Speaker 1: for some reason, there's this pulse of of killer electricity
Speaker 1: and it goes into their house and it turns all
Speaker 1: the appliances against them, so the TV starts trying to
Speaker 1: kill them and everything, a real maximum over drive scenario,
Speaker 1: but it's like it's sold as like the the malevolence
Speaker 1: is delivered directly through the electrical wires the wrong voltage
Speaker 1: or something. Yeah, I guess so. Yeah, I was thinking
Speaker 1: about this, like, what are some other examples of electric
Speaker 1: creatures or humanoids? And I mean, obviously I thought of
Speaker 1: of of electric Christopher Lambert from from Mortal Calm that
Speaker 1: another fighting game. Yeah, but but so many, So often
Speaker 1: is the case you see individuals with some sort of
Speaker 1: pyrotechnic mobility, you know, Like one of a film that
Speaker 1: we've talked about before has been the Toby Hooper film,
Speaker 1: in which Brad Dorriff played a like a pyromaniac who
Speaker 1: could catch things on fire with his brain. He's got
Speaker 1: like like pyro kinesis, but he doesn't want it. He's
Speaker 1: not like a you know, a villain out there like
Speaker 1: Piro and the X Men just throwing fireballs wherever he wants.
Speaker 1: It's more like every he's kind of like the Hulk.
Speaker 1: He's like fire Hulk. Every time he gets upset, he
Speaker 1: starts catching things on fire. But he also like burns
Speaker 1: the heck out of himself too, which wasn't a nice twist.
Speaker 1: And of course Brad Dorriff is wonderful and in that
Speaker 1: film there are at least portions of it where he's
Speaker 1: it's it's a rare film or Brad Dorriff is the
Speaker 1: lead and he's sort of playing a regular human in
Speaker 1: some of the scenes. So it's interesting to see. But
Speaker 1: but so often is the case you see fire based
Speaker 1: powers in these characters and creatures as opposed to electric
Speaker 1: based powers. And it's kind of weird when you think
Speaker 1: about it, because, as we'll discussing this episode, electricity is
Speaker 1: more tied in with biology than fire. And even from
Speaker 1: the human perspective perspective, you know who among us has
Speaker 1: not harnessed the power of electricity by by walking across
Speaker 1: a carpeted floor in the wintertime and then shocking somebody
Speaker 1: with a touch. You do that on purpose? I have
Speaker 1: in the past done it on purpose. Yes, yeah, but
Speaker 1: it's pretty not announce of guilt on your face. Well,
Speaker 1: one of one of the things I do like to
Speaker 1: do when it gets cold, when the conditions are just right,
Speaker 1: have my son go down a curly slide, build up
Speaker 1: static electricity, and then give me a high five on
Speaker 1: the way down. And at times it has been stiff
Speaker 1: enough to like leave a numbness in my hand when
Speaker 1: you feel it in your wrist, kind of in the bone. Creepy,
Speaker 1: real shocking power. I don't know if there's ever been
Speaker 1: like an actually really scar airy electricity monster movie. The
Speaker 1: other main one I was thinking of is one of
Speaker 1: my favorite cheesy, mid mid career West Craven movies, which
Speaker 1: is Shocker. I think that's from nineteen or so and
Speaker 1: it's gotten Mitch Peleggi or Poleggie, the guy who plays
Speaker 1: Skinner on the X Files. Uh. He plays the villain.
Speaker 1: He's like a serial killer who does some like evil
Speaker 1: black magic ritual to turn himself into electricity after he
Speaker 1: gets killed in the electric chair. That's right. I remember
Speaker 1: saying I never saw it, but I remember seeing the
Speaker 1: boxes for it, and he's in an electric chair on
Speaker 1: the You should see it sometime. It's a laugh riot,
Speaker 1: and he's, oh, he's just like acting, I mean beat
Speaker 1: galaxies beyond normal levels of acting. Is uh would you
Speaker 1: say it's an electric performance? I would say he is
Speaker 1: a live wire. But yeah, so I think you're right
Speaker 1: about the idea that maybe electric monsters should be more
Speaker 1: biologically intuitive than pyrokinetic or fire throwing monsters or even
Speaker 1: fire breathing wagons, because you know, it shouldn't come as
Speaker 1: any surprise that the use of electricity by living organisms
Speaker 1: predates the technological uses predates you know, Tesla and medicine
Speaker 1: or even Franklin and Galvani and all that. Like, all
Speaker 1: kinds of animals use electricity in various ways. Now they're
Speaker 1: they're really noticeable charismatic uses of electricity, like how sharks
Speaker 1: and rays have electric sensory organs known as the ampullae
Speaker 1: of Lorenzini, which they used to sense very faint electric
Speaker 1: currents transmitted through water by potential prey animals. And then
Speaker 1: you've got the electrogenic organisms that like generally aquatic organisms
Speaker 1: that emit strong electric currents maybe just stun prey or
Speaker 1: two deploys a defensive weapon. And these would include things
Speaker 1: like electric fish, electric catfish and rays. Yeah. Yeah, the
Speaker 1: electric eel is certainly the electric animal par excellence. Uh,
Speaker 1: though it's always worth reminding everyone, and it's not really
Speaker 1: an eel. It has more it's more related to a catfish. Oh,
Speaker 1: I don't think I knew that. Well, I didn't know
Speaker 1: they were electric catfish, but I didn't know the eel
Speaker 1: was one. Right, Yeah, I mean you look at it
Speaker 1: if you' you know, fortunate enough to see one in
Speaker 1: a tank somewhere or in the wild. Uh, you know,
Speaker 1: you're gonna notice that it doesn't really look like an eel.
Speaker 1: It's uh, it's it's it's a very curious looking creature.
Speaker 1: Have you ever seen a de fleshed eel skull? Oh?
Speaker 1: I don't know that I have. It is one of them.
Speaker 1: Is usually don't leave them on when I go. You should.
Speaker 1: You should look up an eel skull. Sometimes it might
Speaker 1: be different for different species, but at least some eel
Speaker 1: skulls are like the most metal thing in nature. It's amazing.
Speaker 1: But anyway, we today we wanted to to think about
Speaker 1: electric organisms. But instead of focusing on these larger organisms
Speaker 1: that use electricity maybe in a sensory capacity or as
Speaker 1: a weapon of some sort. We wanted to go down
Speaker 1: to zoom in with the microscope and to take a
Speaker 1: look at the world of micro organisms that deal in
Speaker 1: the currency of the Holy fire, the amber, the electricity.
Speaker 1: So I just wanted to start by saying by giving
Speaker 1: a shout out that I got the idea to do
Speaker 1: this episode after I read a really interesting article a
Speaker 1: couple of weeks ago in the New York Times by
Speaker 1: previous stuff to blow your mind. Guest Carl Zimmer, Oh, yes, yeah,
Speaker 1: that was a tremendous episode. It was great to chatting
Speaker 1: with him. I'd love to have him back on the show.
Speaker 1: Sometimes we should see about that. If we're getting back
Speaker 1: on the show, then he becomes a friend of the show.
Speaker 1: That's the way it works two appearances. Two appearances make
Speaker 1: you a friend of the show. So just one is previous. Guest.
Speaker 1: I almost said friend of the show, but I didn't
Speaker 1: want to presume. I think those are the rules. Yes,
Speaker 1: uh so, of course. Electricity. You know, it's generally thought
Speaker 1: of as the flow of electrons. You might have other
Speaker 1: ways of defining it. You could maybe define it other
Speaker 1: ways in terms of electrical potential, like a positive or
Speaker 1: negative charge, but Generally, if you've got current, if you've
Speaker 1: got electrons flowing that, you think of that as some
Speaker 1: form of electricity. And there are ways in which the
Speaker 1: metabolism of our bodies could be considered electric. For example,
Speaker 1: what is actually happening when we breathe. I don't know
Speaker 1: if I've ever thought of it quite this way before,
Speaker 1: but I was reading an article in New Scientists from
Speaker 1: July which quotes the u c l A microbiologists Kenneth
Speaker 1: Nielsen in characterizing the most basic biochemistry of life as
Speaker 1: a flow of electrons. So basically, think about it like this.
Speaker 1: You eat carbon based compounds, you take in that chemical energy,
Speaker 1: and that's gonna be molecules like sugars, and these molecules,
Speaker 1: these carbon based compounds like sugars, have excess electrons, and
Speaker 1: then cells in the body break down those compounds and
Speaker 1: they pass on the extra electrons through a series of
Speaker 1: chemical reactions that power the body, and part by making
Speaker 1: a dinascene triphosphate or a t P, which is the
Speaker 1: chemical energy transport molecule that that captures the energy obtained
Speaker 1: through the breakdown of food, and then he uses it
Speaker 1: to power things that happen inside ourselves. I've I've sometimes
Speaker 1: seen a TP characterized as an energy storage molecule, but
Speaker 1: that's not quite right. That would be more like fats
Speaker 1: or sugars or something. A TP is like, it's like
Speaker 1: a car for energy, you know, it carries it from
Speaker 1: one place to another in the cell. And apparently the
Speaker 1: flow of electrons is an indispensable part of making that
Speaker 1: a TP that powers our cells. But eventually the extra electrons,
Speaker 1: since they're flowing, they've got to go somewhere at the
Speaker 1: end of this chain of chemical reactions. You can't just
Speaker 1: keep building up extra electrons in the body until you
Speaker 1: become a humanliding jar or you become the guy from
Speaker 1: Shocker and you just electrocute people by touching them. So
Speaker 1: you have to pass on the electrons onto a molecule
Speaker 1: that will accept them. And in our case, that molecule
Speaker 1: is oxygen. You breathe in the oxygen, and that oxygen
Speaker 1: we breathe in goes around to the body, to the cells,
Speaker 1: and it accepts those extra electrons that are the waste
Speaker 1: product of our metabolism. Uh and it bonds with carbon molecules,
Speaker 1: and then you breathe out this waste product as CEO
Speaker 1: two And to quote from this researcher Kenneth Nielsen, as
Speaker 1: as quoted in in New Scientist, that's the way we
Speaker 1: make all our energy, and it's the same for every
Speaker 1: organism on this planet. Electrons must flow in order for
Speaker 1: energy to be gained. This is why when someone suffocates
Speaker 1: another person, they're dead within minutes. You have stopped the
Speaker 1: supply of oxygen, so the electrons can no longer flow.
Speaker 1: So choking somebody is kind of like it's like putting
Speaker 1: a resistor in the electric circuit. That's interesting. I mean,
Speaker 1: this is all getting down to the fact that we're
Speaker 1: all essentially bioelectric organisms. Yeah, that's exactly right, and it's
Speaker 1: not just us, Like this is basically the rule for
Speaker 1: all kinds of life forms, from humans to coconut crabs
Speaker 1: to lots of single celled organisms. Pretty much every organism
Speaker 1: needs to create an electron flow by taking in food
Speaker 1: with excess electrons and then running that through a series
Speaker 1: of chemical reactions to extract usable energy for cells, and
Speaker 1: then dumping those electrons out into some kind of electron
Speaker 1: accepting waste bucket like oxygen molecules. And this is even
Speaker 1: true for bacteria where from any species, oxygen must be
Speaker 1: present as this terminal receptor for the electrons at the
Speaker 1: end of the metabolic line. But there are some prokaryotic organisms,
Speaker 1: single celled organisms that can't or don't use oxygen, and
Speaker 1: these are known as anaerobic bacteria, and they live in
Speaker 1: places where oxygen doesn't reach or where oxygen is very limited.
Speaker 1: And the examples of this might be places like deep
Speaker 1: in the sediment along a river, or buried in a
Speaker 1: sea bed, or even ever a deep underground in oil wells.
Speaker 1: I mean, try to imagine that that far underground, that
Speaker 1: like life is thriving in some way. We've also talked
Speaker 1: about them thriving in some human created sewer environments. Absolutely, yeah, yeah, yeah,
Speaker 1: all all these environments, especially these environments that are cut
Speaker 1: off from the surface by by mud or sediment or
Speaker 1: even by vast expanses of dead rock. So if the
Speaker 1: electrons have to flow for life to go on, how
Speaker 1: do these anaerobic bacteria survive without oxygen molecules to accept
Speaker 1: the excess electrons at the end of the metabolism and
Speaker 1: basically to breathe out. How you know, where do the
Speaker 1: electrons go when they're done? With them. So here's where
Speaker 1: we get to a bacterial discovery story. So in the
Speaker 1: mid nineteen eighties, I think around nine seven, the American
Speaker 1: microbiologist Derek Lovely was out pulling up samples of sediment
Speaker 1: from the Potomac River. And one of these samples from
Speaker 1: the Potomac River, it was around Washington, d C. Contained
Speaker 1: one of these weird single celled organisms. It was a
Speaker 1: bacterium called geo bacter metalla reducens. And like other bacteria,
Speaker 1: this bacterium would begin the electron flow of its metabolism
Speaker 1: by consuming organic compounds that had excess electrons. For example, ethanol,
Speaker 1: which is alcohol. So there's some ethanol in its environment.
Speaker 1: It can eat that, but it would end its metabolism
Speaker 1: by passing the excess electrons off into iron oxides, which
Speaker 1: are rust So this is a life form that can
Speaker 1: survive by eating grain, alcohol and breathing out rusty iron. Yeah.
Speaker 1: I've read and Lovely some of some of his papers
Speaker 1: that when they're working within the lab, they essentially just
Speaker 1: feeded vinegar. Yeah, that that's that's all it requires. Wow,
Speaker 1: So if you have to breathe out into rusty iron,
Speaker 1: would you rather survive by eating only grain alcohol or
Speaker 1: by eating only vinegar. Um. I feel like vinegar from
Speaker 1: for me, vinegar would probably be healthier for you for
Speaker 1: men is my personal choice, but I am I'm not
Speaker 1: a microbe. So just as an interesting side note, in
Speaker 1: this process, the bacteria, Carl Zimmer notes the sent this
Speaker 1: article to bacteria help transform the regular old iron oxides
Speaker 1: the rust particles in their environment into the naturally fair
Speaker 1: magnetic mineral known as magnetite. So that's like, you know,
Speaker 1: the strong natural magnetic rock you might find in sediments
Speaker 1: or around the world, and these bacteria helped produce that
Speaker 1: magnetite by by by pushing off these electrons into it,
Speaker 1: which sort of magnetizes it. Now we've been speaking kind
Speaker 1: of metaphorically by calling this bacterial process breathing, because it's
Speaker 1: not breathing in the exact same way we do. Like
Speaker 1: the bacteria don't have respiratory systems with lungs and alveola
Speaker 1: and all that. We breathe by sucking in oxygen and
Speaker 1: then transporting it around our bodies to the cells where
Speaker 1: it needs to go, and then breathing out the molecular
Speaker 1: waste products of our metabolism through the same gas exchange
Speaker 1: system in the lungs. But the bacteria don't have lungs.
Speaker 1: They don't suck rust particles into the body to allow
Speaker 1: the electrons to attach to them. Uh, and so what's
Speaker 1: going on there? Like according to Carl Zimmer's article, it
Speaker 1: took Lovely and his colleague Dr John Stolts in their
Speaker 1: labs years to figure out how this respiration process was
Speaker 1: taking place. And what they discovered was that instead of
Speaker 1: like sucking in the rust particles and breathing them out,
Speaker 1: geobacter exhaled by putting out electric wires. Yeah, this is amazing.
Speaker 1: And of course when we're saying wires, we're talking about microfilaments. Yeah,
Speaker 1: but they do, in a way function like electric wires.
Speaker 1: I mean, they're they're conductive. They are long, filamentous kind
Speaker 1: of conductive material that is there to transmit a flow
Speaker 1: of electrons between potentials. So you've got to build up
Speaker 1: of electrons as a waste product in the bacterium, and
Speaker 1: then you've got a lower potential thing out there that
Speaker 1: can accept them, like maybe a deposit of iron oxide,
Speaker 1: and you pump the electrons out through this wire to
Speaker 1: the iron oxide outside the cell. Yeah, and we're these
Speaker 1: things are tiny too. We're talking about like three nanometers
Speaker 1: in diameter. Yeah, extremely too. Though they can get pretty
Speaker 1: long without Yeah, we can get pretty long in some
Speaker 1: cases some cases. And then we'll get into other species later.
Speaker 1: But there are species with with with a filaments. Yeah.
Speaker 1: Uh So, when you're a geobacter and you since the
Speaker 1: presence of iron oxide and your surroundings, basically what it
Speaker 1: seems like you do is you sprout out these microscopic
Speaker 1: little filaments, each one known as a pealis plural peely
Speaker 1: and bacterial peely. Are fascinating in other respects too, because,
Speaker 1: for one thing, they play a role in the bacterial
Speaker 1: process known as horizontal gene transfer. And we've done a
Speaker 1: podcast on this before. This is a really interesting phenomenon. Basically,
Speaker 1: bacteria they don't have sex in the way that like
Speaker 1: sexually reproducing eukaryotic animals do. Write they reproduce a sexually,
Speaker 1: meaning they make exact copies of themselves in a process
Speaker 1: called binary fission. They split off and create two daughter cells,
Speaker 1: not by mating with other individuals and combining their DNA
Speaker 1: to create an ad mixed offspring. But despite this, despite
Speaker 1: them not having sexual reproduction. Bacteria do engage in something
Speaker 1: kind of like sex, and this is this process of
Speaker 1: horizontal gene transfer where bacteria can meet up and share
Speaker 1: genetic material between one another. And this doesn't always work
Speaker 1: out great for us, because, for example, it is one
Speaker 1: of the main methods by which bacteria acquire DNA for
Speaker 1: antibiotic resistance. We just did an episode of our other podcast, Invention,
Speaker 1: about the invention of antibiotics and antibiotics are you know,
Speaker 1: a miraculous invention of the twentieth century. But one of
Speaker 1: the big problems with them is that over time, the
Speaker 1: diseases that we're fighting get better at overcoming these medicines. Yeah,
Speaker 1: I think. I think the way we put it in
Speaker 1: that episode is with with penicillin and another antibiotics, we're
Speaker 1: we're stealing a weapon from the you know, the eons
Speaker 1: old war between fungi and bacterium and uh, and we've
Speaker 1: stole the weapon, but the but the war continues on
Speaker 1: and the the the the evolution of their warfare continues. Yeah,
Speaker 1: and in the way we use the fungal weapon sort
Speaker 1: of accelerates the arms race, like provoked, it's in a
Speaker 1: Cold War style like provokes the other side to uh
Speaker 1: make go with a with a build up, you know,
Speaker 1: an arms build up, when that seems to be what's
Speaker 1: happening on the bacterial side. Now we stole like a
Speaker 1: fungal catapult, but now we're quickly advancing into the age
Speaker 1: of where a fungal tribute SHA would be a more
Speaker 1: appropriate That's right. We have to find those those fungal
Speaker 1: tributes or develop them ourselves. I hope we do. But
Speaker 1: for the but for the bacteria to share their own
Speaker 1: tribute shape plans. What one of the things they do
Speaker 1: is this horizontal gene transfer process. Specifically this process known
Speaker 1: as conjugation, where to bacteria meet up and they're like,
Speaker 1: let's hook up, and they extend a PEALSS between the
Speaker 1: donor bacterium and the recipient bacterium and this little hair
Speaker 1: like filament hooks them together so they can share plasmids,
Speaker 1: which are little segments of DNA and peely also enhanced
Speaker 1: the virulence of bacteria by helping them bind two cells
Speaker 1: in the host body. And this is the case in
Speaker 1: disease causing strains of bacteria like strepped A caucus or
Speaker 1: an E. Coli. The pelists can kind of hook them
Speaker 1: onto the cells lining your the inside of your throat
Speaker 1: or in your gut, or wherever it is they're trying
Speaker 1: to infect. But in the case of Geobacter, the researchers
Speaker 1: who worked with Geobacter originally concluded that the peely we're
Speaker 1: being used for another purpose entirely, and that purpose was
Speaker 1: the off routing of electricity into electro receptive molecules in
Speaker 1: the environment. So to picture this as again, this is
Speaker 1: going to be a very crude metaphor, but imagine if
Speaker 1: you were to breathe instead of by sucking oxygen into
Speaker 1: your lungs and exhaling CEO two, by shooting electric wires
Speaker 1: out of your mouths into the environment, which would then
Speaker 1: attack hatch to the toaster and the TV and pour
Speaker 1: waste electricity out of your lungs into those appliances. Oh,
Speaker 1: that's pretty good. That sounds like a good electric alien
Speaker 1: creature for a future film or a pass film, I
Speaker 1: mean movies done. Yeah, I mean I can imagine Dan
Speaker 1: Ackroyd playing a character that does this, uh, you know,
Speaker 1: back in the nineties or so. Oh, you know, they're
Speaker 1: one of those nineties like a kind of grimy computer
Speaker 1: monster movies. What was that one that Jamie Lee Curtis
Speaker 1: was in about like a killer computer virus that like
Speaker 1: just puts gross wires everywhere. Oh yeah, this was I
Speaker 1: think Donald Sutherland was in it. Yeah, it's not a
Speaker 1: ship or something. It was really bad. It was like
Speaker 1: a sort of it was kind of a take on
Speaker 1: the thing, but with this this cybernetic blend of like
Speaker 1: wires and flesh. Uh yeah, yeah, it's like a computer
Speaker 1: virus that decides that Earth is that the humans are
Speaker 1: a pathogen and virus. I think you're a pathogeny. It's
Speaker 1: called virus. Yeah, And I should notice a As a
Speaker 1: follow up to what I was just saying about the
Speaker 1: bacterial peely, it's not fully settled whether the Geobacter actually
Speaker 1: use peely as their electric wires, or whether they use
Speaker 1: peely exclusively. Karl Zimmer's article notes that the Yale physicist
Speaker 1: and Nikkil S. Malvankar and colleagues believe that instead the
Speaker 1: bacteria use dedicated wires made out of organic compounds called cytochromes,
Speaker 1: but the fact that Geobacter does pump electrons out through
Speaker 1: biological wires of some sort doesn't seem to be in dispute.
Speaker 1: It's just their different ideas about to what extent they're
Speaker 1: using different structures as the wires. All right, on that note,
Speaker 1: we're going to take a quick break, but we'll be
Speaker 1: right back. Than alright, we're back. So we've been talking
Speaker 1: about the idea of electroactive bacteria, bacteria that in some
Speaker 1: metaphorical since breathe by releasing excess electrons that are the
Speaker 1: the end product of their metabolism into uh things in
Speaker 1: their environment, like little deposits of iron oxide. And they
Speaker 1: do this by sticking these wires out of their cells
Speaker 1: that that connect to things, and they can pump the
Speaker 1: electricity out through those wires. But it doesn't stop there
Speaker 1: because researchers have also discovered that in some cases, the
Speaker 1: electric wires put out by metal reducing bacteria like Geobacter
Speaker 1: would not just go out into iron oxide in the
Speaker 1: environment or into other metals in the environment, but sometimes
Speaker 1: these wires would go out and connect to other species
Speaker 1: of electroactive bacteria. And so the same way that Geobacter
Speaker 1: metaphorically breathes by putting out electron flow, some species of
Speaker 1: bacteria can metaphorically eat by taking in electron flow. And
Speaker 1: this energy intake allows the bacteria to convert carbon dioxide
Speaker 1: into methane, kind of like how plants use direct energy
Speaker 1: from the sunlight to how or the chemical reaction that
Speaker 1: turns carbon dioxide from the air into the sugars and
Speaker 1: the carbon compounds that make up the bodies of plants.
Speaker 1: When I'm sure if said in a million times on
Speaker 1: the show, but one of my favorite crazy facts about
Speaker 1: plants is they make their bodies from the air. They
Speaker 1: don't make their bodies from you know, the dirt or something,
Speaker 1: and that that it's it's the carbon from the carbon
Speaker 1: dioxide in the atmosphere that becomes the wood beings of
Speaker 1: air and sun basically totally well and to be fair
Speaker 1: and like water from the ground and other minerals and stuff,
Speaker 1: but primarily, yes, primarily of air and sun. So yeah,
Speaker 1: So if these bacterial species that that do this, if
Speaker 1: they pair up, they can form these like cross networks
Speaker 1: of underground bacterial wires where one species feeds another with
Speaker 1: its waist electricity. So I was reading a BBC article
Speaker 1: on electroactive bacteria by an author named Jasmine Fox Skelly,
Speaker 1: and this article mentioned that it was not long after
Speaker 1: loveliest discovery of the electrical properties of Geobacter that the
Speaker 1: u c l A microbiologist Kenneth Nielsen, who was quoted
Speaker 1: in that article earlier describing all of you know, the
Speaker 1: respiration of life is the flow of electrons before Nielsen
Speaker 1: found another electronic screening bacterium, this one in the Oneida
Speaker 1: Lake of New York State and published his findings in
Speaker 1: the journal Science. And this was a very similar story,
Speaker 1: except the bacterium here was not geobacter. It was shoe
Speaker 1: and Ella on identis uh and and much the same
Speaker 1: way that the geobacter metaphorically breathes iron oxide, this bacterium
Speaker 1: breathe this oxygen when it's available, but when it's not,
Speaker 1: it breathes manganese oxide, pumping electrons out into the external
Speaker 1: deposits of the compound, though it can also pump electrons
Speaker 1: out into other metals like iron but um. Unlike Geobacter,
Speaker 1: which uses some form of wire to canuct electricity, quote,
Speaker 1: she and Ella appears to shuttle electrons out of their
Speaker 1: cells using transport molecules called flavians and stepping stone proteins
Speaker 1: embedded in the outer membrane called cytochromes. So there we've
Speaker 1: got this cytochromes being involved again. So we're starting to
Speaker 1: build up a picture that there are many different ways
Speaker 1: for bacteria to kind of breathe electrically or be electro
Speaker 1: active in one way or another. And these tend to
Speaker 1: be bacteria that that don't have access to air, or
Speaker 1: don't or only do this win they don't have access
Speaker 1: to air, and so so Carl Zimmer's article also discusses
Speaker 1: the work of Danish microbiologist Lars Peter Nielsen. And this
Speaker 1: is a different spelling of Nils different Nielson. You know,
Speaker 1: this is a two Nielsen night, but it's once an
Speaker 1: in e A L and one's an in I E L. Personally,
Speaker 1: no offense to the other guy, but I'm more of
Speaker 1: an inn I E L kind of guy. Yeah, it
Speaker 1: stands out a little bit more so. This guy, l
Speaker 1: Is Peter Nielsen, discovered an electrical bacterial ecosystem within the
Speaker 1: mud from the Bay of our Hoosts. I hope I'm
Speaker 1: saying that right. It's a coastal area on the western
Speaker 1: side of the main peninsula of Denmarks are roos A
Speaker 1: A R h U s. So basically, within a core
Speaker 1: of mud sample here, you'd have bacteria lower down down
Speaker 1: in the mud with anaerobic metabolism. Again, that means oxygen free.
Speaker 1: They don't need oxygen to live, and they would produce
Speaker 1: hydrogen sulfide is a waste product of their way of life.
Speaker 1: And hydrogen sulfide we've talked about, I'm sure plenty of
Speaker 1: times on the show before. It's a it's a poisonous
Speaker 1: gas that smells like rotten eggs. It's just like it's
Speaker 1: bad stuff. It smells like death. You'd commonly find it
Speaker 1: in places where biological material is being decomposed in the
Speaker 1: absence of oxygen, so again anaerobic decomposition. Like you will
Speaker 1: smell this stuff wafting up out of swamps and out
Speaker 1: of sewers and stuff like that. It was one of
Speaker 1: the bye products that people had to protect their faces
Speaker 1: from when they went down to fight the soap dragon fat. Yeah.
Speaker 1: The fact, I don't know why I said protect their faces.
Speaker 1: I mean like wear gas maths, right, I don't mean
Speaker 1: like it's going to hurt their faces out at them
Speaker 1: and try to attachs. It's like the face hugger U No, No,
Speaker 1: like it's like you don't want to breathe it um now,
Speaker 1: of course, in order for you to smell hydrogen sulfide.
Speaker 1: In order to smell this nasty bacterial byproduct in a
Speaker 1: mar Shura sewer, the gas has to bubble up to
Speaker 1: the surface and waft out right. But Nielsen noticed that
Speaker 1: it wasn't doing that in this mud. Something was consuming
Speaker 1: this poisonous waste product before it buoyed up to the
Speaker 1: surface of the mud and escaped. But as Karl Zimmer
Speaker 1: writes in his article, if other bacteria below we're breaking
Speaker 1: down this hydrogen sulfide without oxygen to aid in the
Speaker 1: metabolic process, again, you would have an unacceptable build up
Speaker 1: of electrons, and so this excess electricity would have to
Speaker 1: go somewhere. And what they found is exactly what you
Speaker 1: might guess. The bacteria were extending biological electric wires built
Speaker 1: out of thousands of cells surrounded by a conductive protein sheath.
Speaker 1: Uh kind of like the you know, the sheath you
Speaker 1: might see on a copper wire to protect it, except
Speaker 1: it's the other way around. In this case. The sheath
Speaker 1: is what's conducting the electricity. So it's kind of like
Speaker 1: if you had like plastic surrounded by copper. I guess
Speaker 1: which would be a bad design. For a wire, but
Speaker 1: it works in this case, and these wires are known
Speaker 1: as cable bacteria. The cable bacteria allow the waste electricity
Speaker 1: to flow out to the surface, and once the electrons
Speaker 1: reach the surface, there you've got surface bacteria which have
Speaker 1: access to oxygen, unlike the bacteria below because they're on
Speaker 1: the surface of course. So these bacteria use the electricity
Speaker 1: to cause a chemical reaction between oxygen and hydrogen, the
Speaker 1: waste product of which is water and quote from Karl's
Speaker 1: article quote and cable bacteria grow to astonishing densities. One
Speaker 1: square inch of sediment may contain as much as eight
Speaker 1: miles of cables. Dr Nielsen eventually learned to spot cable
Speaker 1: bacteria with the naked eye. Their wires look like spider
Speaker 1: silk reflecting the sun. Beautiful, and you can look at
Speaker 1: pictures of this. Actually I agree, they do look kind
Speaker 1: of like spider silk. They're kind of, uh, these glistening,
Speaker 1: almost invisible filaments that can kind of catch the light
Speaker 1: in certain ways. Very beautiful. But one cool thing that
Speaker 1: I guess we have to consider is they're discovering that
Speaker 1: these electroactive bacteria are found all over the place. They're
Speaker 1: abundant in ecosystems throughout the world. And given how abundant
Speaker 1: these electroactive bacteria are, it's not inconceivable that they play
Speaker 1: a major role in regulating various forms of geochemistry, like
Speaker 1: maybe regulating what kinds of minerals you would find in
Speaker 1: the top soil producing magnetite, maybe regulating the chemistry of
Speaker 1: the atmosphere, or regulating the chemistry of the oceans. Right, So,
Speaker 1: I mean other tay come here is that this is
Speaker 1: not just some rare, obscure thing that you encountering only
Speaker 1: like you know, some sort of bizarre extreme environment. But
Speaker 1: they're they're they're found all over and could have a
Speaker 1: very important role. Now, primarily the examples we've been looking
Speaker 1: at so far have been bacteria that sort of pump
Speaker 1: out electricity in order to metaphorically breathe. You know, the
Speaker 1: electricity is this waste product, so the extra electrons have
Speaker 1: to be disposed of and to something that will accept them.
Speaker 1: But we already mentioned that it does go both ways.
Speaker 1: Like also mentioned in Fox Skellies article for the BBC
Speaker 1: is the idea that um that scientists have been finding
Speaker 1: more bacteria that simply are able to consume pure electricity
Speaker 1: that can assume electrons when they need to, and she
Speaker 1: gives the example of a University of Cincinnati microbiologists named
Speaker 1: in net Row who's found several bacterial species that live
Speaker 1: on the ocean floor and apparently they can live off
Speaker 1: of pure electrical current if they need to. It's not
Speaker 1: that they naturally make make their lives this way, but
Speaker 1: it seems like this is something that they are able
Speaker 1: to to sustain themselves without dying for a period of time.
Speaker 1: So if I understand correctly, this is different than an
Speaker 1: organism that just like thrives on pure electricity with no food.
Speaker 1: But there there is even evidence of, like you know,
Speaker 1: we were talking earlier about these relationships between electroactive organisms
Speaker 1: and one bacterium having electricity as a waste product and
Speaker 1: then routing it to a bacterium that will accept it
Speaker 1: as a as an incoming energy product. And there's even
Speaker 1: evidence of like cross species or cross organism type electrical
Speaker 1: grids spanning different kingdoms of life, and this example being
Speaker 1: the electrical cooperation between bacteria and archaea in deep ocean
Speaker 1: floor habitats that are rich with methane. Uh to to
Speaker 1: quote from Fox Skellies article. The archaea feed on electrons
Speaker 1: from methane, oxidizing the gas to generate carbonate. They then
Speaker 1: pass the electrons onto their partner bacteria along the nano wires,
Speaker 1: which act like power cables. Finally, the bacteria deposit the
Speaker 1: electrons onto sulfate, producing energy that the cell can use
Speaker 1: in the process. And so we don't know how far
Speaker 1: back these types of relationships go, but it's easy to
Speaker 1: imagine these these types of cooperation evolving billions of years ago,
Speaker 1: especially before Earth's atmosphere underwent the Great Poisoning when all
Speaker 1: the oxygen showed up. All right, we're gonna take a
Speaker 1: quick break. When we come back, we're going to get
Speaker 1: to an area that a lot of you are probably
Speaker 1: thinking about, Like, you know, if we have we're talking
Speaker 1: about the organisms that they utilize electricity, they are producing
Speaker 1: these these nano filaments. Uh, then there's got to be
Speaker 1: a way that we could harness that power ourselves put
Speaker 1: them to work. Yeah, that's exactly what we're going to
Speaker 1: discuss when we come back. Than alright, we're back. So
Speaker 1: if you're listening to this this podcast via some sort
Speaker 1: of an electronic device, I mean, we electronics are are
Speaker 1: kind of our thing right as a species. And so
Speaker 1: it stands to reason that as we discover these these
Speaker 1: these bacteria that are they're using electricity, that are that
Speaker 1: are creating these little filaments that we eat envisioned ways
Speaker 1: to again harness their power. I don't know about you.
Speaker 1: I listen to my podcast by plugging directly into bacterial maps,
Speaker 1: like I've got a I've got a big stroma light
Speaker 1: in my house, and I just jack in, Well, that's
Speaker 1: not that's not as as as crazy distant from the
Speaker 1: reality the possible realities we're going to discuss, as one
Speaker 1: might think, it's it's a little crazy, but but yeah,
Speaker 1: when you when you think about the is actual electroactive
Speaker 1: bacteria that there do seem to be some potentials just
Speaker 1: one example, Like, there are all kinds of ideas where
Speaker 1: people have talked about using electroactive bacteria as as potential
Speaker 1: electrical sources, but one of the many ideas I came
Speaker 1: across was to use the electrical potential of geobacter for
Speaker 1: small scale energy purposes. In Peru, so I was reading
Speaker 1: a few articles from about how researchers at the University
Speaker 1: of Engineering and Technology in Peru were pioneering a method
Speaker 1: to draw usable electricity directly from the soil, specifically using
Speaker 1: the outflow of electrons from the respiration of geobactors. Now
Speaker 1: this is meaningful in in the context of what they
Speaker 1: were doing in Peru, because some villages and dwellings in
Speaker 1: the Peruvian rainforest don't have connections to the electrical grid.
Speaker 1: Mini don't at the time uh they were doing this project.
Speaker 1: The project leaders claimed that it was like forty two
Speaker 1: of villages and in the rainforest did not have connections,
Speaker 1: and those that do have connections are at risk to
Speaker 1: lose power entirely when lines are knocked out by floods,
Speaker 1: has happened in March, and so this means of course,
Speaker 1: after it gets dark, people can't read, kids can't study
Speaker 1: for school unless they use like kerosene lamps, which are
Speaker 1: apparently unhealthy and are hard on the eyes. I can
Speaker 1: imagine that. So this method, developed by ut EC in
Speaker 1: partnership with a company called FCB Mayo, works to charge
Speaker 1: batteries and power led lamps with a special bioelectric box.
Speaker 1: And the box has a plant on top with roots
Speaker 1: planted in the soil and then electrodes plunged into this
Speaker 1: grid of little soil buckets that are full of geobactors,
Speaker 1: and the metabolic interaction between the plant and the geobactors
Speaker 1: generates excess electric charge in the soil, and that electric
Speaker 1: charge gets routed up through the electrodes that are planted
Speaker 1: in the soil, whisks those free electrons away to charge
Speaker 1: of battery, which in turn powers the LED lamp. Now
Speaker 1: we're not sure how scalable this individual technology is, but
Speaker 1: it shows the general principle that you can draw small,
Speaker 1: at least small amounts of power or electricity directly from
Speaker 1: electric bacteria and the soil when other power sources are
Speaker 1: not readily available. And this seems possibly like an interesting
Speaker 1: alternative to say, you know those small scale solar panels
Speaker 1: that you see being used to power individual devices or lights,
Speaker 1: you know, things like that, like various garden gnomes and
Speaker 1: whatnot that light up or their garden gnomes they get power. Yeah,
Speaker 1: I think so, you see, this is like the main
Speaker 1: place I feel like one tends to see this sort
Speaker 1: of technology, like little little lights that go in your
Speaker 1: yard that have a little solar panel on them, you know. Uh,
Speaker 1: but oh, I guess I've just never seen one mounted
Speaker 1: in a gnome. But I see it now. It can
Speaker 1: have red light up eyes. Yeah, I mean, I assume
Speaker 1: there's a there has someone has had to have created
Speaker 1: one with the numb But you know, it's one thing
Speaker 1: to to power an led ed lamp. But I think
Speaker 1: this does drive home that even if you're only talking
Speaker 1: about producing such small amounts of electricity to power uh,
Speaker 1: you know, you know, very low energy lighting effects, that
Speaker 1: still can make a huge difference in the right circumstances. Yeah,
Speaker 1: it can. And you can imagine using elements of this
Speaker 1: bacterial electro biology in concert with other technologies UH, to
Speaker 1: build up more capabilities. Like in his Times article, Carl
Speaker 1: Zimmer mentions that a Cornell University researcher UH named Buzz
Speaker 1: Barstow and colleagues are trying to figure out if bacteria
Speaker 1: could be of use when paired with solar panels, so
Speaker 1: not in place of them, but working in concert with them,
Speaker 1: and the ideas that the solar panels would convert the
Speaker 1: sunlight into electric current, which would then be routed into
Speaker 1: bacterial wires down down to these colonies of bacterium called
Speaker 1: shoe and Ella. That's the one I mentioned earlier that
Speaker 1: was discovered in Lake Oneida shoe and ella, and that
Speaker 1: could use the energy from the electrons to metabolize organic
Speaker 1: compounds and turn it into fuel. This would really be
Speaker 1: key for for carbon fixation. So so the studying question
Speaker 1: here is two thousand nineteen study title Electrical Energy Storage
Speaker 1: with Engineered Biological Systems, published in the Journal of Biological Engineering,
Speaker 1: and we're essentially talking it kind of comes back to
Speaker 1: the virus movie we're talking about because we're essentially talking
Speaker 1: about a cybernetic energy storage system a synthesis of biological
Speaker 1: and non biological electrochemical engineering. The authors point out that
Speaker 1: non biological methods for using electricity for carbon fixation they
Speaker 1: started to match and even exceed the capability of microbes,
Speaker 1: but that biological methods are better at pumping out the
Speaker 1: complex sort of complex molecules that are ultimately necessary for
Speaker 1: biofuels and polymers. So it's it's kind of a way
Speaker 1: to improve, you know, the photosynthesis in this situation, like
Speaker 1: you think of it as like photosynthesis plus or photosynthesis
Speaker 1: two point oh. So it's like making in our official tree,
Speaker 1: except it's a solar panel and a bunch of bacteria. Yeah,
Speaker 1: well yeah, it's like it's it's part bacteria, part solar
Speaker 1: system technology and uh and and the results, yeah, can
Speaker 1: could could help with carbon fixation. Yeah. Another thing Carl
Speaker 1: mentions is that the electrical bacterial filaments could be used
Speaker 1: as some form of sensors, like a little little tiny
Speaker 1: electro sensitive or conductive wires can be useful to you know,
Speaker 1: essentially for signaling purposes. He gives the example of, uh,
Speaker 1: you know, being attached to some kind of wearable technology
Speaker 1: that would touch the skin, and these little bacterial nano
Speaker 1: wires could detect chemical changes in the properties of our sweat,
Speaker 1: and that might be biologically useful information that could be
Speaker 1: transmitted to a device that might tell you, I don't
Speaker 1: know what, you know, there's something wrong with your sweat, dude,
Speaker 1: you need to Yeah. Yeah, just basically, you know, this
Speaker 1: gets into the whole area of like to whatever extent
Speaker 1: we can develop dependable like real time biomonitoring, medical medical
Speaker 1: monitoring technology like this kind of a you know, a
Speaker 1: huge positive impact on human health. But yeah, so Carl.
Speaker 1: Carl mentioned specifically the work of Derek Lovely again. Uh so,
Speaker 1: you know, again the guy who discovered geobacter and and
Speaker 1: has since expanded in into discovering several other microbe species,
Speaker 1: just as other researchers have also discovered other MicroB species
Speaker 1: that have these capabilities. And he's pointed out that while
Speaker 1: geobacters filaments are super thin, like three nanometers in diameter,
Speaker 1: some are more. Really, some of the more recently discovered
Speaker 1: bacteria have fatter filaments, and Uh and this is especially
Speaker 1: useful for us if we're looking to manipulate them. If
Speaker 1: you want to manipulate them into some sort of an
Speaker 1: electronic device like a nano wire sensors that we're talking about,
Speaker 1: it pays to have something a little on a you know,
Speaker 1: a slightly larger scale so that we can we can
Speaker 1: actually work with it. Lovely and Uh and his co authors.
Speaker 1: They also point out that protein nano wire like this
Speaker 1: would have a number of advantage over silicon nano wires.
Speaker 1: So if we're talking about the biocompatibility, the state of
Speaker 1: the stability, the potential for modification into various biomolecules and
Speaker 1: quote chemicals of medical or environmental interest, and plus the
Speaker 1: sustainable method of producing these nano wires will make it
Speaker 1: easier to build the sort of devices we're trying to
Speaker 1: make and hoping to make in the future. Uh. He
Speaker 1: points out that we've been making the thimble sized amounts
Speaker 1: of the sort of you know, wire materials that we
Speaker 1: need for for the future we're trying to build. But
Speaker 1: what we need we need buckets of them. We need
Speaker 1: buckets of these nano wires. And this is a possible
Speaker 1: means by which we can grow buckets of nano wires. Oh,
Speaker 1: it almost sounds like the early penicillin problem, you know,
Speaker 1: with the Oxford researchers in the lab and they were
Speaker 1: working with Alexander Fleming strain of penicillin. We talked about
Speaker 1: this in a recent episode of Invention. Uh. You know,
Speaker 1: they could they could create this penicillin from the Penicillium fungus,
Speaker 1: the mold, but they couldn't make enough of it that
Speaker 1: it would be useful. Like the first time they tried
Speaker 1: to treat somebody with it who had a deadly infection.
Speaker 1: The guy was successfully treated for a few days, but
Speaker 1: the guy with the infection eventually died because they ran
Speaker 1: out of penicillin. They just couldn't make enough of it.
Speaker 1: And they later Uh, it only broke through as a
Speaker 1: medicine because they discovered a more productive strain that could
Speaker 1: make more of the stuff. Yeah, And I want to
Speaker 1: come back to the the the the the sustainability aspect
Speaker 1: of this too. The idea here being that if you know,
Speaker 1: you could have these these devices and when they're done,
Speaker 1: you're not just like it's not going into a dump,
Speaker 1: it's not potentially being you know, part of some sort
Speaker 1: of toxic waste. It is just biodegrading into the environment.
Speaker 1: Oh yeah, I mean, electronic waste is actually a big deal.
Speaker 1: Like we you know, we we don't see a lot
Speaker 1: of it. But what happens to all these electronic components
Speaker 1: when we're done with them and the thing breaks and
Speaker 1: you just throw it away. The possibility being able to
Speaker 1: grow these things, I mean obviously that's that that would
Speaker 1: have tremendous advantage. Yeah. Absolutely, And and that they'd be biodegradable.
Speaker 1: You just you know, some other bacterium just eats them
Speaker 1: up when you're done. But another thing that I've read
Speaker 1: about these electroactive bacteria is that some of them are
Speaker 1: extremely good candidates for the bioremediation of waste, including toxic
Speaker 1: and radioactive waste, where they can take something like you
Speaker 1: know a type of radioactive waste s like, you know,
Speaker 1: a type of uranium, and they can, through their their
Speaker 1: metabolic process, reduce that uranium to say, a less soluble form.
Speaker 1: So they're not going to completely destroy it, but they
Speaker 1: might change it into a form that makes it less
Speaker 1: damaging to the environment. And the same could be true
Speaker 1: for other forms of pollution. Another another thing I've seen
Speaker 1: it referenced is the the idea of using bacteria like
Speaker 1: this to clean up oil spills. You know that they
Speaker 1: can like eat eat hydrocarbons that are in places they
Speaker 1: shouldn't be, right, plastic waste being another another big one. Yeah,
Speaker 1: So it's interesting We've been championing fungi on the show
Speaker 1: for a little bit here, and now it's it's bacteria's
Speaker 1: time to shine. We're back in the land of Jubilex. Yeah.
Speaker 1: Jubile X being the d n d uh demon lord
Speaker 1: of slimes and oozes, which in the bast episode we
Speaker 1: kind of associated loosely with bacteria, and it is the
Speaker 1: arch enemy of Zogdamoy, the demon lord of Funga. I
Speaker 1: raised the flag of Jubilex for today. Yes, that's my side,
Speaker 1: all right, So there we have it. Um, there's you know,
Speaker 1: they're There are various areas here where we could branch off,
Speaker 1: so you know, if you're interested in hearing more episodes
Speaker 1: about about bacteria or about various means of dealing with
Speaker 1: radioactive waste, but we would love to hear from you
Speaker 1: in the meantime. Check out stuff to All Your Mind
Speaker 1: dot com. That's where you find all the episodes, and
Speaker 1: if you want to support the show, you can tell
Speaker 1: some friends about it, tell family members about it, tell
Speaker 1: household pets about our show, and then make sure you
Speaker 1: rate and review us wherever you have the power to
Speaker 1: do so. Huge thanks as always to our excellent audio producer,
Speaker 1: Maya Cole. If you'd like to get into touch with
Speaker 1: us with feedback on this episode or any other, to
Speaker 1: suggest a topic for the future, or just to say hello,
Speaker 1: you can email us at contact at stuff to Blow
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