Bacillus suaedae sp. nov., isolated from the stem of Suaeda aralocaspica in north-west China

Abstract

A bacterial strain, designated YZJH907-2T, was isolated from the stem of Suaeda aralocaspica, collected from the southern edge of the Gurbantunggut desert, Xinjiang, PR China. Cells of strain YZJH907-2T were Gram-stain-positive, aerobic and rod-shaped. They formed white or colourless circular colonies with smooth convex surfaces. Strain YZJH907-2T grew at 4-50 °C (optimum, 28-30 °C), pH 7.0-10.0 (optimum, pH 8.0-9.0) and with 0-10 % (w/v) NaCl (optimum, 3-7 %). The genomic DNA G+C content of strain YZJH907-2T was 38.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequence similarity showed that the strain was most closely related to Bacillus alcalophilus DSM 485T (97.37 %), Bacillus kiskunsagensis B16-24T (96.87 %) and Bacillus bogoriensis LBB3T (96.71 %). Average nucleotide identity values between YZJH907-2T and B. alcalophilus DSM 485Tand B. bogoriensis LBB3T were 69.2 and 69.0 %, respectively. Digital DNA-DNA hybridization values of YZJH907-2T with B. alcalophilus DSM 485T and B. bogoriensis LBB3T were 19.6 and 20.4 %, respectively. The cell wall of strain YZJH907-2T contained meso-diaminopimelic acid, and the major and secondary isoprenoid quinones were MK-7 and MK-5, respectively. Results of fatty acids showed that anteiso-C15 : 0, iso-C15 : 0 and C16 : 0 were the predominant cellular fatty acids. Two-dimensional thin-layer chromatography analysis indicated that the polar lipids included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, three unidentified phospholipids and two unidentified glycolipids. Based on the genomic, phylogenetic and phenotypic analyses, strain YZJH907-2T represented a novel species of the genus Bacillus, and thus the name Bacillus suaedae sp. nov. is proposed. The type strain is YZJH907-2T (=CGMCC 1.18763T=KCTC 43335T).