The mechanisms of extracellular electron transfer

Abstract

In bioelectrochemical systems (BESs) microbial activity facilitates electricity generation and product synthesis. Using the microbial process of extracellular electron transfer (EET) Shewanella and Geobacter species can respire using a solid terminal electron acceptor, such as an anode in BES. Study of these microorganisms and how they behave at the molecular level is important for shining light on geomicrobial processes and development of BES. Through the use of molecular and electrochemical techniques, this PhD thesis will focus on the molecular mechanisms employed by bacterial biofilms on the anode of a BES, specifically Shewanella oneidensis MR-1 and Geobacter sulfurreducens DL-1. The physiology of these microorganisms appears to be directly associated with the operational conditions of the BES. The application of electrochemical and molecular studies enables the comparison and understanding of the cellular response to the BES operation, in particular on how they respond to changes in the anode potential. Quantitative proteomics from low biomass, biofilm samples is not well documented.

Anode potential influences the structure and function of anodic electrode and electrolyte-associated microbiomes

“…3). High electrode potentials (+597 to +797 mV vs SHE) have previously been shown to reduce current production and degrade proteins in Shewanella oneidensis MR-114 and Geobacter sulfurreducens 15.…”