How electricity-generating microbes can keep going, and going - faster
BY DEREK LOVLEY
Electricigens, the microbes that can completely oxidize organic compounds to carbon dioxide and then transfer the electrons derived from that oxidation onto the anode of a microbial fuel cell, are the Energizer Bunnies of the microbe world. They gain energy to support their growth and metabolism from the electron transfer to anodes, resulting in low-maintenance, self-sustaining fuel cells that can run indefinitely. But for many proposed applications of microbial fuel cells, the rate at which electricigens convert organic matter to electricity will need to be substantially increased.
As far as we know there has been no evolutionary pressure on electricigens to generate electricity in natural environments. Their electricigenic abilities are likely a fortuitous benefit of growing in anoxic soils and sediments with insoluble Fe(III) and Mn(IV) oxides as the electron acceptor. It is not clear whether proteins that ...
