title: Desulfosporomusa polytropa gen. nov., sp. nov., a novel sulfate-reducing bacterium from sediments of an oligotrophic lake.
abstract: Five strains of sulfate-reducing bacteria were isolated from the highest positive dilutions of a most probable number (MPN) series supplemented with lactate and inoculated with sediments from the oligotrophic Lake Stechlin. The isolates were endospore-forming and were motile by means of laterally inserted flagella. They stained Gram-negative and contained b-type cytochromes. CO difference spectra indicated the presence of P582 as a sulfite reductase. Phylogenetic analyses of the 16S rDNA sequences revealed that the isolates were very closely affiliated with the genus Sporomusa. However, sulfate and amorphous Fe(OH)(3), but not sulfite, elemental sulfur, MnO(2), or nitrate were used as terminal electron acceptors. Homoacetogenic growth was found with H(2)/CO(2) gas mixture, formate, methanol, ethanol, and methoxylated aromatic compounds. The strains grew autotrophically with H(2) plus CO(2) in the presence or absence of sulfate. Formate, butyrate, several alcohols, organic acids, carbohydrates, some amino acids, choline, and betaine were also utilized as substrates. The growth yield with lactate and sulfate as substrate was 7.0 g dry mass/mol lactate and thus two times higher than in sulfate-free fermenting cultures. All isolates were able to grow in a temperature range of 4-37 degrees C. Physiologically and by the presence of a Gram-negative cell wall, the new isolates resemble known Desulfosporosinus species. However, phylogenetically they are affiliated with the Gram-negative genus Sporomusa belonging to the Selenomonas subgroup of the Firmicutes. Therefore, the new isolates reveal a new phylogenetic lineage of sulfate-reducing bacteria. A new genus and species, Desulfosporomusa polytropa gen. nov., sp. nov. is proposed.
authors.affiliation: Institut für Chemie und Biologie des Meeres, Universität Oldenburg, Carl-von-Ossietzky Strasse 9-11, 26111 Oldenburg, Germany. sassh@earth.cf.ac.uk
authors.forename: Henrik
authors.initials: H
authors.lastname: Sass
authors.forename: Jörg
authors.initials: J
authors.lastname: Overmann
authors.forename: Heike
authors.initials: H
authors.lastname: Rütters
authors.forename: Hans-Dietrich
authors.initials: HD
authors.lastname: Babenzien
authors.forename: Heribert
authors.initials: H
authors.lastname: Cypionka
mesh_terms: D015373:Bacterial Typing Techniques; D045303:Cytochromes b / Q000378:metabolism; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification; D004275:DNA, Ribosomal / Q000737:chemistry / Q000302:isolation & purification; D004725:Endospore-Forming Bacteria / Q000145:classification / Q000302:isolation & purification; D005290:Ferric Compounds / Q000378:metabolism; D005407:Flagella; D005618:Fresh Water / Q000382:microbiology; D020459:Genes, rRNA; D019015:Geologic Sediments / Q000382:microbiology*; D006090:Gram-Negative Bacteria / Q000145:classification / Q000302:isolation & purification; D008969:Molecular Sequence Data; D009068:Movement; D010084:Oxidation-Reduction; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000378:metabolism; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013431:Sulfates / Q000378:metabolism*; D050864:Sulfite Reductase (NADPH); D013696:Temperature; D045854:Veillonellaceae / Q000145:classification* / Q000166:cytology / Q000302:isolation & purification / Q000502:physiology*; D014871:Water Microbiology
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005290:Ferric Compounds; D012336:RNA, Ribosomal, 16S; D013431:Sulfates; C021024:ferric hydroxide; D045303:Cytochromes b; D050862:Oxidoreductases Acting on Sulfur Group Donors; D050864:Sulfite Reductase (NADPH)