Quorum sensing improves current output with Acidithiobacillus ferrooxidans

Abstract

Summary Acidithiobacillus ferrooxidans is a strict acidophilic chemolithoautotrophic bacterium that obtains its energy from reduced inorganic sulfur species or ferrous 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‐ AHL s). Electrode coverage during pre‐colonization was sparse regardless of the electron donor source, whereas activation of quorum sensing significantly enhanced it. Microbial fuel cells ( MFC s) 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 −0.56 A m −2 by concomitantly using iron‐based metabolism and C14‐ AHL s. Cyclic voltammetry displayed different electrochemical reactions in relation to the nature of the electron donor, underlying the implication of different electron transfer mechanisms.

Key findings

• ▸Quorum sensing enhances electrode coverage during pre-colonization.
• ▸Microbial fuel cells with pre-colonized electrodes produce more current when iron is used as an electron donor.
• ▸Biocathode coverage and current output increase significantly when iron-based metabolism is used.

Keywords

Identifiers

DOI

10.1111/1751-7915.12797

Journal

Microbial Biotechnology

Year

2017