May 24, 2011

Research Opens Doors To Microbial Electricity

A breakthrough discovery has scientists using bacteria to generate energy, putting us a step closer to harnessing the possibilities, according to a study published in Proceedings of the National Academy of Sciences (PNAS).

For the first time, the study, funded by the British Biotechnology Council and the U.S. Department of Energy, demonstrated the exact molecular structure of the proteins which enable bacterial cells to transfer electrical charge through microscopic "wires" found to be sticking through their cell walls.

Shewanella oneidensis is a bacteria type that lives in oxygen-free environments, and can be seen as an attractive power source for everything from lights to mobile phone chargers, reports Reuters.

The knowledge of the exact structure of the bacteria and their atom-sized wires will allow researchers to design electrodes to create efficient microbial "fuel cells or bio-batteries."

"Now we have a blueprint of what the battery looks like, says lead author Dr. Tom Clarke of the University of East Anglia (UEA) School of Biological Sciences.

"The advance could also hasten the development of microbe-based agents that can clean up oil or uranium pollution, and fuel cells powered by human or animal waste," reports the study.

Clarke says, "This is an exciting advance in our understanding of how some bacterial species move electrons from the inside to the outside of a cell.

"Identifying the precise molecular structure of the key proteins involved in this process is a crucial step towards tapping into microbes as a viable future source of electricity," he says.

He also points out that "all living things generate electricity; it's not the stuff of science fiction." For instance, humans use electricity to pump the heart and make the brain think.

Even with the discovery, it is still several years off before such bacteria usage becomes efficient, but the findings could speed up the development of microbe-based agents to clean up oil or uranium pollution and use of fuel cells powered by sewage or compost.

In fact, Clarke believes that microbes might be enlisted to clean up any accidents such as Japan's Fukushima plant disaster in March.

"These bacteria don't need energy-rich fuels. They can take in oil slicks, waste oil ... degrade it and at the same time produce energy," Clarke says.


Image Caption: The bacterium Shewanella oneidensis strain MR-1 (above) may offer a biological solution for remediating US sites contaminated during the manufacture of nuclear weapons. Credit: Public Library of Science/Wikipedia (CC BY 2.5)   


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