Somewhere in a small water-filled vessel at Radboud University, a community of ancient microbes feeds on methane and, in doing so, quietly sends electrons into a metal electrode. For years the question hovering over this strange metabolism was how the current actually traveled from living cell to metal, and now the answer has been seen: the organisms spin their own conductive nanowires to carry it. It is a reminder that life has long been generating electricity in ditches and trenches, unnoticed, and that as the world searches for new ways to make energy, the answers may already be humming in
Methane-Eating Microbes Grown on Electrodes Build Conductive Nanowires to Carry Electricity
Once a month in ditches; once every five days on an electrode
Mark
So what's actually new here? The microbes making electricity from methane was already reported.
Mimi
Right, that came four years ago. What's new is the how. They've now seen the nanowires under a special microscope, carrying electrons from the microbes to the electrode.
Luke
And worth noting, the source says the team strongly suspected this already. It's a confirmation by direct visualization, not a surprise.
Mark
The growth rate stands out. Once a month in ditches, once every five days on electrodes.
Mimi
Yes, and that speed matters because it helped them reach a culture that is 95 percent ANME, which hasn't been done before.
Luke
Those numbers come from Welte herself, as the lead researcher. We don't have independent comparison here, though the paper is in Nature Communications.
Mark
Why does purity matter so much?
Mimi
Welte says you can study the microbes far better when they aren't growing mixed with everything else.
Mark
And the energy angle? Hydrogen, electricity from methane?
Mimi
She says in theory it could beat an electrolyzer in efficiency, with a practical use maybe 20 years out.
Luke
Keep that as a theoretical claim and a rough guess. She also says the technique is currently far too expensive and complex. No cost figures or output numbers are given, so we can't say how much current these cultures produce.
El Pulso
- Methane-eating ANME archaea have been shown to push electricity through nanowires they build themselves, a mechanism researchers had long suspected but never directly saw.
- A near-pure culture, 95 percent ANME, has been grown for the first time, turning a tangled microbial community into something scientists can finally study on its own terms.
- On electrodes in the lab the microbes divide every five days, while in nature they manage roughly once a month, a gap that makes the lab a fast track for discovery.
- Turning this biological current into hydrogen or a practical power source remains roughly two decades away and is, for now, too costly and intricate to deploy.
- The team is now pressing on with detailed studies of the nanowires and the organisms' electrical behavior, with each refinement inching the technique toward greater efficiency.
Somewhere in a small water-filled vessel at Radboud University, a community of ancient microbes feeds on methane and, in doing so, quietly sends electrons into a metal electrode. For years the question hovering over this strange metabolism was how the current actually traveled from living cell to metal, and now the answer has been seen: the organisms spin their own conductive nanowires to carry it. It is a reminder that life has long been generating electricity in ditches and trenches, unnoticed, and that as the world searches for new ways to make energy, the answers may already be humming in the simplest of cultures.
In a water-filled vessel in Cornelia Welte's lab at Radboud University, a community of microbes clings to an electrode, feeding on methane and pushing electrons into the metal. Their small electric current has a path, and the team's new work in Nature Communications reveals it: nanowires the microbes build themselves.
The organisms are anaerobic methanotrophic archaea, known as ANME. Welte and her colleagues reported four years ago that they turn methane into electricity, but the mechanism stayed hidden. Other microbes were known to grow nanowires; nobody had confirmed that ANME did too. Now, with a specialized microscope, the researchers have watched the current travel through those self-made wires. Welte says the team had long suspected it and had been searching for these answers for a long time.
The lab also revealed that ANME thrive on a lightly charged electrode, multiplying far faster than they do in nature, where they divide about monthly, while on the electrodes they divide every five days. That speed let the team reach a culture that is 95 percent ANME, something never achieved before, and a near-pure community is far easier to study. Welte credits partners including researchers from Yale.
The practical future is still distant. The current could in principle make hydrogen, and the microbes may generate power more efficiently than an electrolyzer, but Welte puts useful applications about 20 years away and calls the present technique far too expensive and complex. She sees the work as a small step toward energy-efficient methods that a world running low on natural resources may need, and the next step is to study the nanowires and the organisms' electrical behavior in greater detail.
In a small water-filled vessel in Cornelia Welte's lab at Radboud University, a community of microbes is being fed methane and clinging to an electrode. They multiply there, and as they feed they push electrons into the electrode, producing a small electric current. New work from Welte and her colleagues, published in Nature Communications, shows how that current gets from the organisms to the metal: through nanowires the microbes build themselves.
The organisms are anaerobic methanotrophic archaea, known as ANME. They consume methane and convert it into electricity, a finding Welte, a microbiologist, and her team reported four years ago. What remained unanswered was the mechanism. Other microorganisms were already known to grow nanowires, but nobody knew whether ANME did.
Now the researchers have seen it. Welte said the team had suspected this for a long time, and that they were finally able to visualize the microbes feeding electricity back to an electrode through their self-made nanowires, using a special microscope. In her words, they had been searching for these answers for a long time.
The lab work turned up a second result. ANME, Welte found, thrive on an electrode carrying a small voltage, and they grow far faster there than in nature. Out in ditches and trenches, she said, ANME divide about once a month. On the electrodes in her lab, they divide once every five days.
That speed helped the team reach something that had not been done before: a culture in which 95 percent of the microbial community is ANME. Welte said a near-pure culture lets researchers study the organisms much more effectively than when everything grows together. She credited collaboration with several partners, including researchers from Yale.
The practical implications are, by Welte's own account, distant. The current the microbes produce could in principle be used to make hydrogen, but she said that is still a long way off. In theory, she said, the microorganisms can generate electricity from methane with a small amount of voltage, much more efficiently than an electrolyzer can. She put a possible practical application at about 20 years away. For now, the team is focused on how ANME work at a fundamental level.
Welte placed the work in a larger frame: as natural resources run out, new energy-efficient ways of generating electricity will be needed, and microorganisms could be one route. But she was plain about the present state of the technique, which she called far too expensive and complex. She hopes it can be made more efficient, and described this research as another small step in that direction. The next step is to use the near-pure cultures to study the nanowires and the organisms' electrical behavior in more detail.
Citas Notables
In theory, the microorganisms can generate electricity from methane using a small amount of voltage, much more efficiently than an electrolyzer can.— Cornelia Welte, Radboud University
The technique is still far too expensive and complex, but this research is another small step toward making it more efficient.— Cornelia Welte, Radboud University (paraphrased)
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