Applied Microbiology and Biotechnology

, Volume 98, Issue 6, pp 2699–2707

H2-dependent azoreduction by Shewanella oneidensis MR-1: involvement of secreted flavins and both [Ni–Fe] and [Fe–Fe] hydrogenases

  • Sébastien Le Laz
  • Arlette Kpebe
  • Jean Lorquin
  • Myriam Brugna
  • Marc Rousset
Environmental biotechnology

DOI: 10.1007/s00253-013-5208-z

Cite this article as:
Le Laz, S., Kpebe, A., Lorquin, J. et al. Appl Microbiol Biotechnol (2014) 98: 2699. doi:10.1007/s00253-013-5208-z

Abstract

In this paper, the hydrogen (H2)-dependent discoloration of azo dye amaranth by Shewanella oneidensis MR-1 was investigated. Experiments with hydrogenase-deficient strains demonstrated that periplasmic [Ni–Fe] hydrogenase (HyaB) and periplasmic [Fe–Fe] hydrogenase (HydA) are both respiratory hydrogenases of dissimilatory azoreduction in S. oneidensis MR-1. These findings suggest that HyaB and HydA can function as uptake hydrogenases that couple the oxidation of H2 to the reduction of amaranth to sustain cellular growth. This constitutes to our knowledge the first report of the involvement of [Fe-Fe] hydrogenase in a bacterial azoreduction process. Assays with respiratory inhibitors indicated that a menaquinone pool and different cytochromes were involved in the azoreduction process. High-performance liquid chromatography analysis revealed that flavin mononucleotide and riboflavin were secreted in culture supernatant by S. oneidensis MR-1 under H2-dependent conditions with concentration of 1.4 and 2.4 μmol g protein-1, respectively. These endogenous flavins were shown to significantly accelerate the reduction of amaranth at micromolar concentrations acting as electron shuttles between the cell surface and the extracellular azo dye. This work may facilitate a better understanding of the mechanisms of azoreduction by S. oneidensis MR-1 and may have practical applications for microbiological treatments of dye-polluted industrial effluents.

Keywords

Shewanella oneidensis MR-1 Amaranth Hydrogen Azo dye Flavins 

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Sébastien Le Laz
    • 1
  • Arlette Kpebe
    • 1
  • Jean Lorquin
    • 2
  • Myriam Brugna
    • 1
  • Marc Rousset
    • 1
  1. 1.CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines, UMR 7281, Institut de Microbiologie de la MéditerranéeAix-Marseille UniversitéMarseille Cedex 20France
  2. 2.Mediterranean Institute of Oceanography (MIO), UMR7294, (CNRS/IRD/AMU), UR235 IRDAix-Marseille UniversitéMarseille Cedex 9France