Electron transfer mechanism in Shewanella loihica PV-4 biofilms formed at graphite electrode

Abstract Electron transfer mechanisms in Shewanella loihica PV-4 viable biofilms formed at graphite electrodes were investigated in potentiostat-controlled electrochemical cells poised at oxidative potentials (0.2 V vs. Ag/AgCl). Chronoamperometry (CA) showed a repeatable biofilm growth of S. loihica PV-4 on graphite electrode. CA, cyclic voltammetry (CV) and its first derivative shows that both direct electron transfer (DET) mediated electron transfer (MET) mechanism contributes to the overall anodic (oxidation) current. The maximum anodic current density recorded on graphite was 90 μA cm − 2 . Fluorescence emission spectra shows increased concentration of quinone derivatives and riboflavi…