title: Desulfotomaculum hydrothermale sp. nov., a thermophilic sulfate-reducing bacterium isolated from a terrestrial Tunisian hot spring.
abstract: A novel strictly anaerobic, moderately thermophilic, sulfate-reducing bacterium, designated strain Lam5(T), was isolated from a hot spring in north-east Tunisia and was characterized phenotypically and phylogenetically. The isolate stained Gram-negative but had a Gram-positive-type cell wall. The strain comprised endospore-forming, slightly curved rod-shaped cells with peritrichous flagella. It did not possess desulfoviridin. Strain Lam5(T) grew anaerobically at 40-60 degrees C (optimally at 55 degrees C) and at pH 5.8-8.2 (optimally at pH 7.1); it did not require NaCl but tolerated concentrations up to 1.5 % (w/v). It utilized lactate, pyruvate, formate, ethanol, butanol, glycerol, propanol and H(2) (plus acetate) as electron donors. Lactate was oxidized and pyruvate was fermented to acetate. Sulfate, sulfite, thiosulfate, As(V) and Fe(III) (but not elemental sulfur, fumarate, nitrate or nitrite) were used as electron acceptors. The G+C content of the genomic DNA was 46.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing showed that strain Lam5(T) was a member of the genus Desulfotomaculum, with Desulfotomaculum putei as its closest relative (96 % similarity to the type strain). On the basis of genotypic, phenotypic and phylogenetic data, strain Lam5(T) represents a novel species of the genus Desulfotomaculum, for which the name Desulfotomaculum hydrothermale sp. nov. is proposed. The type strain is Lam5(T) (=DSM 18033(T) =JCM 13992(T)).
authors.affiliation: IRD, UMR 180, Microbiologie et Biotechnologie des Environnements Chauds, IFR-BAIM, ESIL, Universités de Provence et de la Méditerranée, 163 Avenue de Luminy, F-13288 Marseille Cedex 09, France.
authors.forename: Olfa
authors.initials: O
authors.lastname: Haouari
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Fardeau
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Cayol
authors.forename: Corinne
authors.initials: C
authors.lastname: Casiot
authors.forename: Françoise
authors.initials: F
authors.lastname: Elbaz-Poulichet
authors.forename: Moktar
authors.initials: M
authors.lastname: Hamdi
authors.forename: Manon
authors.initials: M
authors.lastname: Joseph
authors.forename: Bernard
authors.initials: B
authors.lastname: Ollivier
mesh_terms: D015373:Bacterial Typing Techniques; D001482:Base Composition; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D045859:Desulfotomaculum / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D020459:Genes, rRNA; D005838:Genotype; D045482:Hot Springs / Q000382:microbiology*; D006358:Hot Temperature; D008969:Molecular Sequence Data; D010641:Phenotype; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D013171:Spores, Bacterial / Q000502:physiology; D013431:Sulfates / Q000378:metabolism*; D016999:Sulfur-Reducing Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D014416:Tunisia
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D013431:Sulfates