Boffins make bacteria-to-energy breakthrough

Researchers have this week revealed that they have unlocked one of the secrets surrounding certain strains of bacteria that are capable of generating electricity, in a breakthrough that could one day allow power plants to generate renewable energy from pools of bacteria.

Scientists have long known that Shewanella bacteria, which are commonly found in soil and water, are capable of converting simple organic compounds, such as lactic acid, into electricity. However, until now they have been unsure as to what drives the process.

Now researchers at the University of Minnesota's BioTechnology Institute claim to have come up with the answer after observing that by increasing vitamin B-2 levels the bacteria produced more power.

"This is very exciting because it solves a fundamental biological puzzle," said Daniel Bond, McKnight land grant professor at the BioTechnology institute. "Scientists have known for years that Shewanella produce electricity. Now we know how they do it."

The researchers found that bacteria growing on electrodes naturally produced the vitamin B-2, which was able to carry electrons from the living cells to the electrodes. Consequently, rates of electricity production from the bacteria increased almost fivefold as the vitamin accumulated.

The researchers now hope larger-scale "microbial fuel cells" using similar bacteria could create enough electricity to power remote sensors on the ocean floor or clean up waste water. "Bacteria could help pay the bills for a wastewater treatment plant," explained Bond.

In the longer term, further scientific advances could also make more ambitious applications possible, such as using bacteria-powered fuel cells to power buildings or cars.