Marine Bacteria Power 'Bio-Battery' Breakthrough: Future of Clean Electricity

It's a new victory for sustainable energy--at least in part. Researchers have made an important breakthrough in the quest to generate clean electricity from bacteria, according to a new study.

The new findings, published in the journal Proceedings of the National Academy of Sciences, reveal that proteins on the surface of bacteria are able to produce an electric current simply by touching a mineral surface. This could have huge implications for the future of battery-powered machines.

In order to make their findings, researchers examined Shewanella oneidensis, a species of marine bacteria. It occurs globally in both rivers and seas--everywhere from the Amazon to the Baltic Sea. They then created a synthetic version of the bacteria using just the proteins thought to shuttle the electrons from the inside of the microbe to the mineral surface that they rested upon. The researchers then inserted these proteins into the lipid layers of vesicles, which are small capsules of lipid membranes--such as the ones that create bacterial membrane. After, they tested how well electrons travelled between an electron donor on the inside and the iron-bearing mineral on the outside.

While researchers knew that bacteria could transfer electricity into metals and minerals and that the interaction depended on special proteins on the surface of the bacteria, they didn't know if the proteins did it directly or indirectly. The scientists' findings, though, showed what really happened.

"This is the first time that we have been able to actually look at how the components of a bacterial cell membrane are able to interact with different substances, and understand how differences in metal and mineral interactions can occur on the surface of a cell," said lead researcher Tom Clarke in a press release. The researchers found that the proteins directly "touched" the mineral surface and produced an electric current.

The findings show that bacteria hold amazing potential to become the "bio-batteries" of the future. It could be a new way to create forms of sustainable energy.

"These bacteria show great potential as microbial fuel cells, where electricity can be generated from the breakdown of domestic or agricultural waste products," said Clarke in a press release.