Quorum sensing improves current output with Acidithiobacillus ferrooxidans
Abstract
Acidithiobacillus ferrooxidans is a strict acidophilic chemolithoautotrophic bacterium that obtains its energy from reduced inorganic sulfur species or fer-rous iron oxidation under aerobic conditions. Carbon felt electrodes were pre-colonized by A. ferrooxidans ATCC 23270 T using ferrous iron or sulfur as electron donors, via the addition (or not) of a mixture of C14 acyl-homoserine lactones (C14-AHLs). Electrode coverage during pre-colonization was sparse regardless of the electron donor source, whereas activation of quorum sensing significantly enhanced it. Microbial fuel cells (MFCs) inoculated with pre-colonized electrodes (which behaved as biocathodes) were more efficient in terms of current production when iron was used as an electron donor. Biocathode coverage and current output were remarkably increased to À0.56 A m À2 by concomitantly using iron-based metabolism and C14-AHLs. Cyclic voltammetry displayed different electrochemical reactions in relation to the nature of the electron donor, underlying the implication of different electron transfer mechanisms.
Domains
Microbiology and Parasitology
Origin : Publisher files allowed on an open archive
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