Isolation and Characterization of a Novel Electrogenic Bacterium, Dietzia sp. RNV-4

SACCO NATALIA J.; BONETTO M. CELINA; CORTÓN EDUARDO

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2017

1932-6203

Electrogenic bacteria are organisms that can transfer electrons to extracellular electronacceptors and have the potential to be used in devices such as bioelectrochemical systems(BES). In this study, Dietzia sp. RNV-4 bacterium has been isolated and identified based onits biochemical, physiological and morphological characteristics, as well as by its 16S rRNAsequence analysis. Furthermore, the current density production and electron transfer mechanisms were investigated using bioelectrochemical methods. The chronoamperometricdata showed that the biofilm of Dietzia sp. RNV-4 grew as the current increased with time,reaching a maximum of 176.6 ± 66.1 mA/m2 at the end of the experiment (7 d); this highlysuggests that the current was generated by the biofilm. The main electron transfer mechanism,indicated by the cyclic voltammograms, was due to secreted redox mediators. By highperformance liquid chromatography, canthaxanthin was identified as the main compoundinvolved in charge transfer between the bacteria and the solid electrodes. Dietzia sp. RNV-4was used as biological material in a microbial fuel cell (MFC) and the current density production was 299.4 ± 40.2 mA/m2. This is the first time that Dietzia sp. RNV-4 has been electrochemically characterized and identified as a new electrogenic strain.