Electron transfer mechanisms in Shewanella loihica PV- 4 viable biofilms formed at graphiteelectrodes were investigated in potentiostat-controlled electrochemical cells poised atoxidative potentials (0.2 V vs. Ag/AgCl). Chronoamperometry (CA) showed a repeatablebiofilm growth of S. loihica PV- 4 on graphite electrode. CA, cyclic voltammetry (CV) andits first derivative shows that both direct electron transfer (DET) mediated electron transfer(MET) mechanism contributes to the overall anodic (oxidation) current. The maximumanodic current density recorded on graphite was 90 μA cm-2. Fluorescence emission spectrashows increased concentration of quinone derivatives and riboflavin in the cell-freesupernatant as the biofilm grows. Differential pulse voltammetry (DPV) show accumulationof riboflavin at the graphite interface, with the increase in incubation period. This is the firststudy to observe a gradual shift from DET to MET mechanism in viable S. loihica PV- 4biofilms.
|Number of pages||5|
|Publication status||Published - 2012|
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
Pastorella, G., Marsili, E., Zhang, X., Barry, N., Pastorella, G., Connolly, J. O., Jain, A., Zhang, X., Woolley, R., & Krishnamurthy, S. (2012). Electron transfer mechanism in Shewanella loihica PV- 4 biofilms formed atgraphite electrode. Bioelectrochemistry, 87, 28-32.