A novel Bacillus strain, designated SYSU G01002T, was isolated from a sediment sample collected from tepid spring in Tengchong, Yunnan province, south-west PR China. The 16S rRNA gene sequence analysis showed that the strain SYSU G01002T shared the highest sequence identity with the type strain of Bacillus alkalitolerans (97.7%). Strain SYSU G01002T grew at pH 6.0-8.0 (optimum, pH 7.0), at 28-55 °C (optimum, 45 °C) and in the presence of 0-2.5% (w/v) NaCl (optimum in the absence of NaCl). It contained meso-2,6-diaminopimelic acid as the cell-wall diamino acid and MK-7 as isoprenoid quinone. The major cellular fatty acids were iso-C15:0, iso-C17:0 and C16:0. The polar were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and unidentified phospholipid. The genomic DNA G + C content was 38.0 mol %. The digital DNA-DNA hybridization and average nucleotide identity values between SYSU G01002T and closely related members of the genus Bacillus were below the cut-off level recommended for interspecies identity. Based on the above results, strain SYSU G01002T represents a novel species of the genus Bacillus, for which the name Bacillus tepidiphilus sp. nov. is proposed. The type strain, SYSU G01002T (= KCTC 43131T = CGMCC 1.17491T).
Keywords: Bacillus; Hot spring; Polyphasic taxonomy.