H2-dependent azoreduction by Shewanella oneidensis MR-1: involvement of secreted flavins and both [Ni–Fe] and [Fe–Fe] hydrogenases
- 548 Downloads
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.
KeywordsShewanella oneidensis MR-1 Amaranth Hydrogen Azo dye Flavins
This work was supported by research grants from the Agence Nationale de la Recherche (EngineeringH2cyano and Algo-H2 projects), the Centre National de la Recherche Scientifique (CNRS), and the Aix-Marseille Université. We are grateful to Dr. Hervé BOTTIN (CEA, LMB, Saclay, France) for kindly providing the AS50, AS51 and AS52 strains of Shewanella oneidensis. We thank Cécile Jourlin-Castelli (CNRS, LCB, Marseille, France) for expert technical assistance and helpful discussions and Marianne Guiral (CNRS, BIP, Marseille, France) for reviewing the manuscript.
- Baffert C, Bertini L, Lautier T, Greco C, Sybirna K, Ezanno P, Etienne E, Soucaille P, Bertrand P, Bottin H, Meynial-Salles I, De Gioia L, Leger C (2011) CO disrupts the reduced H-cluster of Fe–Fe hydrogenase. A combined DFT and protein film voltammetry study. J Am Chem Soc 133:2096–2099PubMedCrossRefGoogle Scholar
- Dawood Z, Brözel VS (1998) Corrosion-enhancing potential of Shewanella putrefaciens isolated from industrial cooling waters. J Appl Microbiol 84:929–936Google Scholar
- Dubrow SF, Boardman GD, Michelsen DL (1996) Chemical pretreatment and aerobic–anaerobic degradation of textile dye wastewater. In: Reife A, Freeman HS (eds) Environmental chemistry of dyes and pigments. Wiley, New York, pp 75–102Google Scholar
- Feng J, Cerniglia CE, Chen H (2011) Toxicological significance of azo dye metabolism by human intestinal microbiota. Front Biosci (Elite Ed) 4:568–586Google Scholar
- Heidelberg JF, Paulsen IT, Nelson KE, Gaidos EJ, Nelson WC, Read TD, Eisen JA, Seshadri R, Ward N, Methe B, Clayton RA, Meyer T, Tsapin A, Scott J, Beanan M, Brinkac L, Daugherty S, DeBoy RT, Dodson RJ, Durkin AS, Haft DH, Kolonay JF, Madupu R, Peterson JD, Umayam LA, White O, Wolf AM, Vamathevan J, Weidman J, Impraim M, Lee K, Berry K, Lee C, Mueller J, Khouri H, Gill J, Utterback TR, McDonald LA, Feldblyum TV, Smith HO, Venter JC, Nealson KH, Fraser CM (2002) Genome sequence of the dissimilatory metal ion-reducing bacterium Shewanella oneidensis. Nat Biotechnol 20:1118–1123PubMedCrossRefGoogle Scholar
- Liebgott PP, Leroux F, Burlat B, Dementin S, Baffert C, Lautier T, Fourmond V, Ceccaldi P, Cavazza C, Meynial-Salles I, Soucaille P, Fontecilla-Camps JC, Guigliarelli B, Bertrand P, Rousset M, Leger C (2010) Relating diffusion along the substrate tunnel and oxygen sensitivity in hydrogenase. Nat Chem Biol 6:63–70PubMedCrossRefGoogle Scholar
- Zollinger (2003) Color Chemistry : syntheses, properties and applications of organic dyes and pigments, 3rd edn. Wiley-VCH, New YorkGoogle Scholar