title: Sodium-dependent succinate decarboxylation by a new anaerobic bacterium belonging to the genus Peptostreptococcus.
abstract: An anaerobic bacterium was isolated from a polluted sediment, with succinate and yeast extract as carbon and energy sources. The new strain was Gram-positive, the cells were coccal shaped, the mol% G+G content of the genomic DNA was 29, and the peptidoglycan was of the L-ornithine-D-glutamic acid type. Comparative sequence analysis of the 16S rRNA gene showed the new strain to belong to the genus Peptostreptococcus. Succinate, fumarate, pyruvate, 3-hydroxybutyrate and lysine supported growth. Succinate was degraded to propionate and presumably CO2, with a stoichiometric cell yield. Key enzymes of the methylmalonyl-CoA decarboxylase pathway were present. The methylmalonyl-CoA decarboxylase activity was avidin-sensitive and sodium dependent, and about 5 mM Na+ was required for maximal activity. Whole cells, however, required at least 50 mM sodium for maximal succinate decarboxylation activity and to support the maximum growth rate. Sodium-dependent energy conservation coupled to succinate decarboxylation is shown for the first time to occur in a bacterium belonging to the group of Gram-positive bacteria containing the peptostreptococci and their relatives.
authors.affiliation: Department of Biological Sciences, University of Waikato, Hamilton, New Zealand.
authors.forename: P H
authors.initials: PH
authors.lastname: Janssen
authors.forename: W
authors.initials: W
authors.lastname: Liesack
authors.forename: C
authors.initials: C
authors.lastname: Kluge
authors.forename: S
authors.initials: S
authors.lastname: Seeliger
authors.forename: B
authors.initials: B
authors.lastname: Schink
authors.forename: C G
authors.initials: CG
authors.lastname: Harfoot
mesh_terms: D001421:Bacteria, Anaerobic / Q000378:metabolism; D002262:Carboxy-Lyases; D002455:Cell Division; D002965:Classification; D003653:Decarboxylation; D006094:Gram-Positive Bacteria / Q000378:metabolism; D043586:Methylmalonyl-CoA Decarboxylase; D008854:Microscopy, Electron; D008858:Microscopy, Phase-Contrast; D008969:Molecular Sequence Data; D010802:Phylogeny; D011422:Propionates / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012964:Sodium / Q000494:pharmacology*; D013386:Succinates / Q000378:metabolism*; D019802:Succinic Acid
chemical_list: D011422:Propionates; D012336:RNA, Ribosomal, 16S; D013386:Succinates; D012964:Sodium; D019802:Succinic Acid; D002262:Carboxy-Lyases; D043586:Methylmalonyl-CoA Decarboxylase; C029658:propionic acid