Electrochemical activity of an Fe(III)-reducing bacterium, Shewanella putrefaciens IR-1, in the presence of alternative electron acceptors

Cyclic voltammetry demonstrated that cells of Shewanella putrefaciens grown under anaerobic conditions without nitrate were electrochemically active. The electrochemical activity was inactivated reversibly by exposure to air, but not by nitrate. Lactate and an applied potential at +200 mV against an Ag/AgCl reference electrode restored the electrochemical activity. These findings can be used to improve the performance of a mediator-less microbial fuel cell using electrochemically active bacteria in the presence of nitrate.