Desulfosporosinus burensis sp. nov., a spore-forming, mesophilic, sulfate-reducing bacterium isolated from a deep clay environment

Abstract

A novel anaerobic, Gram-positive, spore-forming, curved rod-shaped, mesophilic and sulfate-reducing bacterium was isolated from pore water collected in a borehole at −490 m in Bure (France). This strain, designated BSREI1T, grew at temperatures between 5 °C and 30 °C (optimum 25 °C) and at a pH between 6 and 8 (optimum 7). It did not require NaCl for growth, but tolerated it up to 1.5 % NaCl. Sulfate, thiosulfate and elemental sulfur were used as terminal electron acceptors. Strain BSREI1T used crotonate, formate, lactate, pyruvate, fructose, glycerol and yeast extract as electron donors in the presence of sulfate. The sole quinone was MK-7. The G+C content of the genomic DNA was 43.3 mol%. Strain BSREI1T had the type strains of Desulfosporosinus lacus (16S rRNA gene sequence similarity of 96.83 %), Desulfosporosinus meridiei (96.31 %) and Desulfosporosinus hippei (96.16 %) as its closest phylogenetic relatives. On the basis of phylogenetic and physiological properties, strain BSREI1T is proposed as a representative of a novel species of the genus Desulfosporosinus , Desulfosporosinus burensis sp. nov.; the type strain is BSREI1T ( = DSM 24089T = JCM 17380T).