Article

Electron transfer and biofilm formation of Shewanella putrefaciens as function of anode potential

Institute of Environmental and Sustainable Chemistry, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany.
Bioelectrochemistry (Amsterdam, Netherlands) (Impact Factor: 2.65). 05/2012; DOI: 10.1016/j.bioelechem.2012.05.002

ABSTRACT Shewanellaceae are among the most widely studied electroactive microorganisms. In this report, we studied the influence of the applied electrode potential on the anodic current production of Shewanella putrefaciens NCTC 10695 under anoxic conditions. Furthermore, we used cyclic voltammetry (CV) and confocal laser scanning mi-croscopy (CLSM) to investigate the microbial electron transfer and biofilm formation. It is shown that the chro-noamperometric current density is increasing with increasing electrode potential from 3 μA cm − 2 at −0.1 V up to ~12 μA cm − 2 at +0.4 V (vs. Ag/AgCl), which is accompanied by an increasing amount of biomass deposited on the electrode. By means of cyclic voltammetry we demonstrate that direct electron transfer (DET) is dominat-ing and the planktonic cells play only a minor role.

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