Khelifi N. auteur aut IRD Ali O. A. auteur aut IRD Roche P. auteur aut IRD Grossi V. auteur aut IRD Brochier-Armanet C. auteur aut IRD Valette O. auteur aut IRD Ollivier Bernard auteur aut IRD Dolla A. auteur aut IRD Hirschler-Rea A. auteur aut IRD text journalArticle eng text/pdf born digital access The thermophilic sulfate-reducing archaeon Archaeoglobus fulgidus strain VC-16 (DSM 4304), which is known to oxidize fatty acids and n-alkenes, was shown to oxidize saturated hydrocarbons (n-alkanes in the range C-10-C-21) with thiosulfate or sulfate as a terminal electron acceptor. The amount of n-hexadecane degradation observed was in stoichiometric agreement with the theoretically expected amount of thiosulfate reduction. One of the pathways used by anaerobic microorganisms to activate alkanes is addition to fumarate that involves alkylsuccinate synthase as a key enzyme. A search for genes encoding homologous enzymes in A. fulgidus identified the pflD gene (locus-tag AF1449) that was previously annotated as a pyruvate formate lyase. A phylogenetic analysis revealed that this gene is of bacterial origin and was likely acquired by A. fulgidus from a bacterial donor through a horizontal gene transfer. Based on three-dimensional modeling of the corresponding protein and molecular dynamic simulations, we hypothesize an alkylsuccinate synthase activity for this gene product. The pflD gene expression was upregulated during the growth of A. fulgidus on an n-alkane (C-16) compared with growth on a fatty acid. Our results suggest that anaerobic alkane degradation in A. fulgidus may involve the gene pflD in alkane activation through addition to fumarate. These findings highlight the possible importance of hydrocarbon oxidation at high temperatures by A. fulgidus in hydrothermal vents and the deep biosphere. specialized alkylsuccinate synthase anaerobic hydrocarbon oxidation Archaea hyperthermophilic PflD AF1449 084 8 11 2153-2166 2014 1751-7362 https://www.documentation.ird.fr/hor/fdi:010062668 10.1038/ismej.2014.58 1751-7362 [F B010062668] https://www.documentation.ird.fr/hor/fdi:010062668 https://www.documentation.ird.fr/intranet/publi/2014/12/010062668.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2015-01-12 2017-08-23 fdi:010062668 fre