1. The electron-bifurcating FeFe-hydrogenase Hnd is involved in ethanol metabolism in Desulfovibrio fructosovorans grown on pyruvate
- Author
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Natalie Payne, Arlette Kpebe, Chloé Guendon, Carole Baffert, Julien Ros, Régine Lebrun, Yann Denis, Laetitia Shintu, Myriam Brugna, Bioénergétique et Ingénierie des Protéines (BIP ), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Plateforme Protéomique [Marseille], Institut de Microbiologie de la Méditerranée (IMM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Plate-forme Transcriptome FR3479, MM-CNRS, Institut des Sciences Moléculaires de Marseille (ISM2), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ANR-11-IDEX-0001,Amidex,INITIATIVE D'EXCELLENCE AIX MARSEILLE UNIVERSITE(2011), and European Project: 7137500(1971)
- Subjects
Ethanol ,Alcohol dehydrogenase ,Electron bifurcation ,Electrons ,NAD ,Microbiology ,Hydrogenase ,Pyruvic Acid ,Ferredoxins ,Aldehyde ferredoxin oxidoreductase ,Desulfovibrio ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,Molecular Biology ,Oxidation-Reduction ,Hydrogen - Abstract
International audience; Desulfovibrio fructosovorans, a sulfate-reducing bacterium, possesses six gene clusters encoding six hydrogenases catalyzing the reversible oxidation of H2 into protons and electrons. Among them, Hnd is an electron-bifurcating hydrogenase, coupling the exergonic reduction of NAD+ to the endergonic reduction of a ferredoxin with electrons derived from H2. It was previously hypothesized that its biological function involves the production of NADPH necessary for biosynthetic purposes. However, it was subsequently demonstrated that Hnd is instead a NAD+-reducing enzyme, thus its specific function has yet to be established. To understand the physiological role of Hnd in D. fructosovorans, we compared the hnd deletion mutant with the wild-type strain grown on pyruvate. Growth, metabolites production and comsumption, and gene expression were compared under three different growth conditions. Our results indicate that hnd is strongly regulated at the transcriptional level and that its deletion has a drastic effect on the expression of genes for two enzymes, an aldehyde ferredoxin oxidoreductase and an alcohol dehydrogenase. We demonstrated here that Hnd is involved in ethanol metabolism when bacteria grow fermentatively and proposed that Hnd might oxidize part of the H2 produced during fermentation generating both NADH and reduced ferredoxin for ethanol production via its electron bifurcation mechanism.
- Published
- 2022