Electricity Generation by Geobacter sulfurreducens Attached to Gold Electrodes

Departments of Microbiology and Chemistry, University of Massachusetts-Amherst, MA 01003, USA.
Langmuir (Impact Factor: 4.46). 05/2008; 24(8):4376-9. DOI: 10.1021/la703469y
Source: PubMed


The versatility of gold for electrode manufacture suggests that it could be an ideal material for some microbial fuel cell applications. However, previous studies have suggested that microorganisms that readily transfer electrons to graphite do not transfer electrons to gold. Investigations with Geobacter sulfurreducens demonstrated that it could grow on gold anodes producing current nearly as effectively as with graphite anodes. Current production was associated with the development of G. sulfurreducens biofilms up to 40 microm thick. No current was produced if pilA, the gene for the structural protein of the conductive pili of G. sulfurreducens, was deleted. The finding that gold is a suitable anode material for microbial fuel cells offers expanded possibilities for the construction of microbial fuel cells and the electrochemical analysis of microbe-electrode interactions.

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Available from: Vincent M Rotello, Sep 29, 2015
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    • "This non-consistency frustrates efforts to compare performances between individual miniaturized MFCs. Recently, gold has been identified as a potential material for MFC anode development (Richter et al., 2008). Gold is highly conductive, can be vapor deposited, and is compatible with a wide array of conventional microfabrication modalities (Ringeisen et al., 2006). "
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    Bioresource Technology 05/2013; 142:672-682. DOI:10.1016/j.biortech.2013.05.061 · 4.49 Impact Factor
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    • "However, the main limitation for full-scale implementation of this technology is the slow anodic electron transfer processes occurring at the biofilm-electrode interface [6]. Common electrochemically active bacteria, such as Geobacter sulfurreducens [7], [8] and Shewanella oneidensis MR-1 [9], [10], have been frequently used to produce bioelectricity in MFCs. Extracellular electron transfer occurs either through membrane associated cytochromes [11], secretion of soluble electron shuttles or mediators [12], [13], [14], or physical conductive appendages, termed as nanowires [15], [16], [17]. "
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    PLoS ONE 05/2013; 8(5):e63129. DOI:10.1371/journal.pone.0063129 · 3.23 Impact Factor
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    • "Analyses are almost invariably made of cells filtered from groundwater, even though at any point in time only a small fraction of the community is suspended [Lehman, 2007]. Iron-reducing bacteria are physically associated with the insoluble ferric minerals they use as electron acceptors [Richter et al., 2008; Williams et al., 2010], and therefore may be underrepresented in groundwater [Flynn et al., 2008]. Phylogenetic studies, for these reasons, have provided little concrete information about how the activities of various functional groups of microorganisms are distributed throughout the subsurface. "
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