Biofilm formation by Shewanella oneidensis MR-1 towards fundamental understanding of anode respiring communities
type: CreativeWork
description: Microbial fuel cells are bioelectrochemical devices where, on the anode, microorganisms oxidize complex carbon sources and reduce the electrode via complex mechanisms of extra-cellular electron transfer (EET). To date, Geobacter sulfurreducens has been identified as producing not only the largest current density but also large population density biofilms, of the known model organisms commonly used within the field. Another common model organism associated with microbial fuel cells is Shewanella oneidensis, containing multiple EET mechanisms and an apparent inability to form multi-layered biofilms in anaerobic culturing, i.e. microbial fuel cell operating conditions. In contrast to G. sulfurreducens, S. oneidensis biofilm formation appears to coincide with oxygen metabolism, with removal of such, prompting biomass detachment. In this study, to overcome obstacles in biofilm formation a method was employed to encapsulate biomass onto the surface of an electrode. This method used the chemical vapor deposition (CVD) of the silica precursor, tetramethyl orthosilicate (TMOS), causing SiO2 to form a porous thin film effectively binding the culture to the electrode surface and acting as an artificial exopolysaccharide (EPS) biofilm binder. As a demonstration of proof, this methodology was applied to novel biocompatible electrode materials (PHBV-CF) and combined with a laccase catalyzed oxygen reduction cathode in a hybrid biological fuel cell. In comparison to the encapsulated anodes, additional experiments were performed to optimize the growth conditions at which S. oneidensis will naturally form biofilms on PHBV-CF. Observations indicated initial biofilm formation occurred at the onset of stationary phase growth in mirco-aerobic and anaerobic cultures, indicating a biofilm response to carbon substrate limitation. This observation was explored further and led to results indicating the importance of intra-cellular carbon fluxes and the subsequent metabolic response of ribofl…
abstract: Microbial fuel cells are bioelectrochemical devices where, on the anode, microorganisms oxidize complex carbon sources and reduce the electrode via complex mechanisms of extra-cellular electron transfer (EET). To date, Geobacter sulfurreducens has been identified as producing not only the largest current density but also large population density biofilms, of the known model organisms commonly used within the field. Another common model organism associated with microbial fuel cells is Shewanella oneidensis, containing multiple EET mechanisms and an apparent inability to form multi-layered biofilms in anaerobic culturing, i.e. microbial fuel cell operating conditions. In contrast to G. sulfurreducens, S. oneidensis biofilm formation appears to coincide with oxygen metabolism, with removal of such, prompting biomass detachment. In this study, to overcome obstacles in biofilm formation a method was employed to encapsulate biomass onto the surface of an electrode. This method used the chemical vapor deposition (CVD) of the silica precursor, tetramethyl orthosilicate (TMOS), causing SiO2 to form a porous thin film effectively binding the culture to the electrode surface and acting as an artificial exopolysaccharide (EPS) biofilm binder. As a demonstration of proof, this methodology was applied to novel biocompatible electrode materials (PHBV-CF) and combined with a laccase catalyzed oxygen reduction cathode in a hybrid biological fuel cell. In comparison to the encapsulated anodes, additional experiments were performed to optimize the growth conditions at which S. oneidensis will naturally form biofilms on PHBV-CF. Observations indicated initial biofilm formation occurred at the onset of stationary phase growth in mirco-aerobic and anaerobic cultures, indicating a biofilm response to carbon substrate limitation. This observation was explored further and led to results indicating the importance of intra-cellular carbon fluxes and the subsequent metabolic response of ribofl…
author: Roy, Jared
language: English
keywords: Microbial fuel cells., Shewanella., Biofilms., Electronic apparatus and appliances--Plastic embedment., Vitamin B2., Cytochromes.
date published: 2013-01-31T08:00:00Z
date modified: 2026-07-24T05:26:42Z
provider: University of New Mexico
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of New Mexico

PropertyValue
property ID: Handle
value: http://hdl.handle.net/1928/22069