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New Life Found That Lives Off Electricity (2016) (quantamagazine.org)
229 points by respinal 54 days ago | hide | past | web | favorite | 79 comments

> The microbes’ apparent ability to ingest electrons — known as direct electron transfer — is particularly intriguing because it seems to defy the basic rules of biophysics. The fatty membranes that enclose cells act as an insulator, creating an electrically neutral zone once thought impossible for an electron to cross. “No one wanted to believe that a bacterium would take an electron from inside of the cell and move it to the outside,” said Kenneth Nealson, a geobiologist at the University of Southern California, in a lecture to the Society for Applied Microbiology in London last year.

One could say the same about Na+, K+, and Ca++. So what's so hard to imagine about electron carriers?

Mitochondria also pump protons across their membranes in order to synthesize ATP. They are thought to be descended from bacteria.

This is literally the plot to like 5% of all Star Trek TNG episodes. Is there anything they don't predict?

Considering the mynocks in The Empire Strikes Back predate STTNG by almost a decade “predict” seems like a strong word. : )

I like Star wars and I like Star Trek, I would never accuse SW of something so grand as 'predicting' anything though. You have reminded me of my favourite definition for Soft Sci fi though.

Soft Sci Fi: Han Solo running around around on an asteroid with only a face mask. (can't find the source right now)


>"Hard science-fiction” is defined as “stories in which Han Solo does not saunter around the surface of an asteroid wearing only an oxygen mask and a leather jacket”


That's a terrible definition of hard science-fiction both because Han Solo never does that[0] and because it leaves way too much room on the hard side for things like, well, Star Trek, which is pretty soft itself.

[0] - Han Solo actually saunters around the inside of a creature whose body contains an atmosphere which inexplicably isn't expelled when the creature has its mouth open; which makes even less sense.

Have you watched "The Expanse"? I like that explosions in space does not make sound and inertia look right in this show, how would you classify it?

I havent seen it no.

I've read one or 2 convincing essays that SW is basically fantasy rather than science fiction. You have princesses getting rescued, and 'magicians', etc.

When you start analysing it, that basically holds. Sci fi should be about holding up a mirror to contemporary issues, or imagine what may be. I suppose the hard/soft difference is how rigorously they think about the mechanics of that, but theres a big grey area in there. I supposes theres an element of no true Scotsman in there, but these aren't hard and fast rules.

To return to my original comment, I don't think there was ever an attempt to predict, or realistically portray anything. TNG I would expect to at least check up on the state of the art was at any particular time. If data uttered something about doing the kessel run in 12 parsecs, I would expect that to be in the context of a thought out space folding drive. I'm still not saying that ST is 'hard' Sci fi, as the multitude of things that happen as you approach warp 10, or the many ways to travel back in time evidence.

How about the Klingon disintegrators that stop at the soles of your boots?

Star Trek is "Wagon Trail" in space. Star Wars is, I think, space opera. The Expanse gives a nod to hard science, and I respect them for trying, but e.g. the gravity is always either 1 or 0 g. i'm not complaining, I think realistic sci-fi would be kind of boring. Like the first half of "2001: A Space Odyssey", it was basically Dr. Heywood taking a plane. A freaking awesome plane to space, but still.

I have a "100 Sci-Fi Movies" DVD set with lots of old movies from a span of decades, and it's pretty clear that at least some sci-fi did start as attempts to do a kind of scenario planning, but there has always been "speculative fiction" depending on how you categorize things. Was Plato's Atlantis science fiction?

> e.g. the gravity is always either 1 or 0 g

In the Expanse TV show yes, it seems that way. However I suspect that is more due to keeping production costs down. In the books, gravity varies all over the place depending on what moon/planet/rock/station the characters are on, and even goes into details describing the differences of spin gravity near the center of a station vs outward.

Yes, sorry, that's what I meant: the TV show. Thanks for pointing that out.

At one point they use CGI to show off Coriolis force on the asteroid, and I took that to be a kind of message from the show, "We know about this stuff but it's too expensive to do all day every day, so here's some science "fan service"." Like I said, I respect them for it. :-)

But where does all the water go on the Asteroid belt ships? In the first season water is like a super precious commodity there, making a huge deal about tiny amounts. But a space ship is a closed system. The water doesn't leak into space. They're in space and somehow able to keep a breathable atmosphere, continuously cleaning and recycling the air. But with water this is somehow hard?

Regardless it's a pretty cool series :)

In the books water is used as reaction mass for propulsion.

Oh nice, that makes sense, I guess.

Plenty of original Star Trek episodes with similar plots (1966–1969). Ex: https://en.m.wikipedia.org/wiki/The_Immunity_Syndrome_(Star_...

However, just because something is and old idea does not mean inclusion does not represent a prediction.

There's room for all the ST and SW fans here. : )

Which is the one with the little wizard boy?

Ah that would be the one with the magic ring

As long as everyone agrees on the correct answer for Kirk vs Picard

Science fiction and scientists have been proposing alternate forms of life for a long time.

I love TNG (and SW) but have to point out that their ideas in many places aren't new.

Example: Silicon based lifeforms

It's in the same column as carbon so we can have similar bonding structure and properties, so why not silicon-based life instead of carbon-based?

"Though eating electricity seems bizarre..."

I think when you get down to the virus and microbe level, there isn't a lot that's truly analogous to our layperson's understanding of "an animal eating a chunk of stuff it found".

Right -- like eating photons seems bizarre too when you frame it that way... Yet we don't find it odd that plants derive energy this way without consuming physical chunks of stuff.

I wonder how long it will be before we can synthesize food directly from electricity and basic elements? I suspect it's coming relatively soon for fats.

Imagine a ball of fat plus a glass of water for lunch. Yummy!!! :)

Can't vouch for this company, but it is apparently happening.


They supposedly create "proteins...produced from CO2, water, and electricity." According to their numbers, yield per unit of water is 10x soy and at least 500x beef.

It's difficult to find detailed info about what they do, but looking at https://news.ycombinator.com/item?id=18344636 the main point is that they are not producing proteins "chemically", they produce Hydrogen and use the Hydrogen as "food" for some bacteria or yeast (I'm not sure) and then they filter the bacteria or yeast, and they sold that as "single-celled protein", that is a mix of protein, fats and carbohydrates and other things (like meat, cheese, ...).

It's important that they also use some vitamins and nutrients, but it's not clear what they mean, and there is a lot of room for cheating here.

With CO2, water and electricity you can produce carbohydrates and fat, but you can't produce proteins because proteins have Nitrogen, so the question is what is their source of Nitrogen?

You can get Nitrogen from the N2 in the air, but it's very difficult to transform the N2 of the air into a form that can be used by living things. Only some bacteria and archaea can do that. But yeast, fungus, animals and plants can't do that. (Some plants (and animals?) host some bacteria to get usable Nitrogen in exchange of food and protection.)

We can transform N2 from the air into ammonia (or something similar) in an industrial plant, it uses a lot of electricity. It's one of the biggest invention of the XX century. Without artificial ammonia the global agricultura production would fall to less than the half of the current level.

So ignoring the source of the Nitrogen in a system to produce proteins is very misleading.

Hmm, looks interesting but I wonder how they actually manufacture proteins. I mean there are tons of aminoacids, all highly complex structures and body needs full set of them in good ratios to digest them. I don't see any technical details on their web, and stuff like "inspired by cleanest air on earth" means nothing really.

Plus protein are only 1 type of body input - what about carbs, fat, minerals, vitamins etc.

It looks like they also include "nutrients & vitamins" in with the process. You need nitrogen for protein so I wasn't really sure how they were making nitrogen from nothing.

I have my doubts about the viability of that for earth based food, but for it's original purpose of making food on Mars (where water is precious and CO2 can be had from the ice cap) it's brilliant.

Hmm, looks interesting but I wonder how they actually manufacture proteins. I mean there are tons of aminoacids, all highly complex structures and body needs full set of them in good ratios to digest them.

Plus protein are only 1 type of body input - what about carbs, fat, minerals, vitamins etc.

I have lost 79lbs on that diet.

79lbs ~= 36kg

Surely we need to measure this in kWh?

36 kg * 37700kJ/kg * 1h/3600s = 377 kWh of energy stored in 36 kg of fat?

Are you also taking vitamin supplements? (I am seriously and legitimately curious.)

I suspect he's being facetious and talking about keto, which isn't literally just water and a glob of fat.

Yes, facetious about keto. Only supplementing with additional salt. Still take a daily multi - otherwise nothing special other than loads of mayo, bacon, cheese, eggs and beef.

Fasting is also an option, usually do that after the holidays or a traveling. Fast for 4 days and im back on pre holiday weight instead of struggling a couple of weeks to loose 3~4 kilos.

You mean you don't eat for 4 days and you lose weight? What magic is this?

Just salt. Sea salt. Lots of it compared to “normal”. You get a taste for it.

Life has forever been hiding in plain sight. Microbes too small to see, living in places we didn't even think to look, surviving off of chemical and electrical metabolisms we never considered. Our challenge has never been finding life, it's been recognizing it.

Isn't our bodies host to most of such life? I always wondered if microbes created us i.e. more complex life so they could thrive. They are single celled and only want to create copies of themselves. Complex life forms like ours wants to create better version of themselves to tackle the environment. It's a win for microbes really

Odd sci-fi for the evening; our body is host to many bacteria, including some which sense the choices of which parallel universes to stay attached to. These sometimes influence our behavior to stay alive; after all, they want the host to live, also. Consistency is good for their river of life and death.

This just reminds me of ... "Life always finds a way" and "Life is nothing but an electron looking for a place to rest".

Chemolithoautotrophy is the technical term and while it is very interesting that more of these lifeforms are discovered, it isn't a new thing.

Check out the video https://youtu.be/3j_gJ2teK5E

Wow, I'm always impressed in which ways life finds its way.


It lives off radiation though. For anyone wandering, OP is talking about fictional molecule from the series The Expanse.

It's a damn good show. So good that I even wrote a blog post about it!


Really? After watching the first two seasons, I got around to reading the first book, and when season 3 rolled around, I just couldn't handle the unnecessary tv drama any longer.

Kids: go read the books!

Season 3 was a major drop off from the quality of the first two seasons.

I can't even remember if I finished the third season now that I think about it ...

> It lives off radiation though.

So do plants, technically.

Any followup research? how does the redox tower of these microbes work?

Not that I know of, but if I see anything new I am going to share it.

Made me wonder if there is a way to use them to generate electricity somehow? Could one of these microbes be modified so you could feed it something and it makes electricity ?

Doubtful. Small scale in a lab? Maybe. There's a reason they had to go a mile underground to collect a sample. Normal atmospheric conditions are likely toxic to the organism.

What we're actually after with this kind of thing is enzyme mechanisms. Enzymes are doing chemistry we've never done in labs before. Maybe we can replicate that chemistry on an industrial scale to solve some problems. Particularly the Fe-S clusters are of real interest, as they're responsible for moving individual (or sometimes pairs) of electrons around.

So what are possible use cases for this? Hydrogen production? Batteries? Electrolysis catalyst?

Or is it 'just' an inefficient oddity?

Well, the existence of an extracellular enzyme that can oxidize iron is pretty cool. I'm sure we could come up with neat uses for that.

One reason we are looking into these "extremophiles", as they're termed, is because electron flow at a molecular level is pretty important when it comes to renewable energy. Things like solar panels and batteries are still environmentally damaging. The DoD and DoE are both very interested in experimenting with methanogens, cyanobacteria, etc, to figure out ways to harness and manipulate electrons from the environment.

The chemical mechanisms these cells employ are typically higher-order and not super useful. The more low level the interaction (e.g. the NiFe hydrogenase referenced in the article), the more potentially useful to us. There may not be one particular plug-and-play use case like there is for say, a PETase, but we currently don't entirely understand how electrons move around in an ordered way, and so elucidating that mechanism is a high priority. At this point we have it narrowed down to Fe-S clusters in enzymes, and some particular organic intermediates.

As with any process of discovery, the lower-level the organism we can investigate, the hopefully clearer picture we can generate.

The progress-bar at the top of the page that shows how much reading you have left is pretty neat UX.

I bet "gamifying" the process of reading an article to completion like that encourages longer visit times too. I'd like to see an A/B comparison of how long a visitor stays on the page with & without that element.

Isn't the scrollbar to the right of most articles a similar function?

Yeah, I've never liked these progress bars—and unfortunately, I'm seeing them all over the place. They're wasted space for functionality the browser provides me already.

Not if two thirds of the length of the page is taken up by comments.

Ads and ridiculously long sidebar

It works perfectly if you switch to reader-mode.

No scrollbar on mobile though

Double edged sword. Too short an article, the progress bar is meaningless. Too long, and there's no way I'm reading until the end. Useful if all the articles are about this length, but even then fades away with frequent readers.

This video said that they found geobecter bacterium that also produce electricity 30 years ago on 2017. Also they said it is everywhere.


Seems different with this one posted here.

I could imagine them modifying the microbes genetically to make something from this process

> Humans and many other organisms get electrons from food and expel them with our breath.


It sorta make sense as a redox reaction https://en.wikipedia.org/wiki/Redox , but it's more difficult to explain in easy terms than what I though.

For simplicity, let's imagine that you eat methane. The reactions is

  CH4(food) + 3 * O2(air)  --> CO2 + 2 * H2O
For simplicity, let's imagine that The Carbon, Hydrogen and Oxygen are more "happy" when they are in a state like in CO2 and H2O. And for simplicity, you split the bound in the molecules and assign a fictional charge to the atoms

  CO2 ~~> C{4+} + 2 * O{2-}
  H2O ~~> 2* H{+} + O{2-}
So in the "happy" state:

* the Oxygen has a fake charge or -2, i.e. it has two additional electron.

* the Carbon has a fake charge or +4, i.e. it has four electrons less the neutral version.

* the Hydrogen has a fake charge or +1, i.e. it has one electron less the neutral version.

Now, how do you decompose the methane in the food:

  CH4 ~~> C{4+} + 4* H{+} + 12 * e-
[Important: This is not the standard notation. Don't use it in a midterm!]

So if you decompose the methane molecule using "happy" atoms, it has 12 more electrons than what you expect. So in some sense, with each methane molecule you get 12 additional electrons.

The oxygen molecule decompose as

  O2 ~~> 2* O{2-} - 4 * e-

Note the minus sign. Each one "wants" 4 electrons.[Important: This is not the standard notation. Never ever a minus operator in a midterm!!!]

So the 12 electrons travel from the methane in the food to the oxygen you have breathed. (I'm not so convinced to use "expel" here.)

With more realistic food the equation is bigger an more difficult, the number of electrons and oxygens molecules change, but it's the same idea.

You can even follow how the electrons travel in the reactions in the mitochondria, https://en.wikipedia.org/wiki/Electron_transport_chain in each step they release a small amount of energy that is collected. [This is a technical detail of the biological part, you can't release a lot of energy altogether and pack it later.]

[Important: Again, this is not the standard notation. Use the standard notation in a midterm. The question was more difficult to explain than I expected I had to use not standard notation. I hope it's clear enough to read the standard notation and understand the idea.]

I feel bad for making you write all this out.

This is still not "get electrons from food and expel them with our breath", is it? We are not stocking up electrons in our bodies, using them somehow, then exhaling spent electrons.

What we are doing is taking in matter with a certain amount of chemical potential, putting out matter with less chemical potential, and capturing the difference. Electrons are intimately involved in this, but they're a bit of an implementation detail.

If you think it as a battery of a fuel cell, you care about the voltage and the charge, not about if it has Lithium or not. In general in the redox reactions (and in batteries) you don't care too much to which atom the electrons are bound (unless you have to build one). So the electrons are the important thing and the molecules are the implementation detail.

> What we are doing is taking in matter with a certain amount of chemical potential, putting out matter with less chemical potential, and capturing the difference. Electrons are intimately involved in this, but they're a bit of an implementation detail.

You are totally correct too. :) It's equivalente to the previos point of view where the electrons are the important part and the molecules are the implementation detail. It is just that sometimes it is easier to think from one point of view and other times it's easier to think from the other point of view.

(Essentially, Volt = Energy / Charge. Since the charge of the electron is fixed, you can convert easily (or use eV to measure the energy).)


If you think about the methane as a charged battery and the carbon dioxide as a discharged battery, then the idea is that the high potencial electron comes from the food and go away as low potencial electrons in the breath. I'm not 100% happy with this analogy, I think I understand it, but I'm not happy. You are not accumulating electrons.

When you lose weight, the biggest result of burning fat is carbon dioxide which gets expelled through your breath


Yes. Same as how plants put on weight from absorbing carbon dioxide from the air. This still doesn't amount to "get electrons from food and expel them with our breath".

Uhm.. there was this show, Revolution.. Just sayin' :D.

Sadly it was discontinued so fast. The plot was pretty cool and refreshing, if you ignore few boring social details. (Or it was a preparation for something special, we’ll never know.)

Layman here...Is it possible life could likely live in the emptiness space as well then?

Where life == self replicating information? Yes, quite unlikely, but yes. Along these lines, see Boltzmann brains.

The rabbit hole you're looking for is "plasma crystals". ;-)

So, like power company employees?

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