Sulfurimonas crateris sp. nov., a facultative anaerobic sulfur-oxidizing chemolithoautotrophic bacterium isolated from a terrestrial mud volcano

A novel mesophilic facultative anaerobic bacterium, strain SN118 T , was isolated from a terrestrial mud volcano in Taman Peninsula, Russia. The cells were Gram-negative, motile, short, straight or curved rods with a single polar flagellum. Growth was observed at 5-40 °C (optimum, 30 °C) and pH 5.5-9.5 (optimum, pH 8.0). Growth of strain SN118 T was observed in NaCl concentrations ranging from 0.5 to 8.0 % (w/v) with an optimum at 2.0-3.0 % (w/v). The isolate grew chemolithoautotrophically with sulfide, elemental sulfur or thiosulfate as electron donor, oxygen, nitrate or nitrite as an electron acceptor and CO 2 /HCO 3 - as a carbon source. Molecular hydrogen or organic substances did not support growth. Nitrate was reduced to N 2 . The dominant fatty acids were C 16 : 1 ω7 c , C 16 : 0 and C 18  :  1 ω7 c . The total size of the genome of the novel isolate was 2 209 279 bp and the genomic DNA G+C content was 38.8 mol%. Results of phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel isolate belonged to the genus Sulfurimonas and was most closely related to Sulfurimonas denitrificans DSM 1251 T (96.74 %). Based on its physiological properties and results from phylogenetic analyses, including average nucleotide identity and in silico DNA-DNA hybridization values, the isolate is considered to represent a novel species of the genus Sulfurimonas , for which the name Sulfurimonas crateris sp. nov. is proposed. The type strain is SN118 T (=DSM 109248 T =VKM B-3378 T ).