Like a household wire carries electrons from wall socket to appliance, bacteria can conduct electricity along tiny wire-like appendages, researchers report online October 11 in the Proceedings of the National Academy of Sciences.
A community of bacteria connected by these gangly nanowires could act as a slimy fuel cell, digesting organic matter and churning out electricity. If a wired-up community of bacteria could be coaxed into participating, the microbes might also gobble up toxic marine sediments or process sewage at waste treatment plants.
Biologists first noticed that deep-sea bacteria grew the curious wires when placed in environments with little oxygen. Rather than suffocate, the microbes grew nanowires made of protein to hunt for pockets of oxygen or other places to dump electrons, says biologist Yuri Gorby at the J. Craig Venter Institute in San Diego. Then the bacteria appeared to share the gas — their way of breathing — by connecting their wires, as if a crowded room of people could breathe from an open window simply by linking hands.