Paraliobacillus quinghaiensis sp. nov., isolated from salt-lake sediment in China

Abstract

A Gram-positive, moderately halophilic, endospore-forming, catalase- and oxidase-positive, obligately aerobic bacterium, designated strain YIM-C158T, was isolated from sediment of a salt lake in the Qaidam Basin, north-west China. Cells were motile with peritrichous flagella and rod-shaped, with meso-diaminopimelic acid in the cell-wall peptidoglycan. Strain YIM-C158T grew in the presence of 1-20 % (w/v) NaCl and pH 6.0-10.0, with optimum growth at 5 % (w/v) NaCl and pH 8.0. The strain grew at 4-50 degrees C, with optimum growth at 37 degrees C. The major cellular fatty acids were anteiso-C(15 : 0), iso-C(14 : 0), C(16 : 0), anteiso-C(17 : 0), iso-C(16 : 0), C(16 : 1)omega7c alcohol and C(16 : 1)omega11c. Strain YIM-C158T contained menaquinone MK-7 as the sole respiratory quinone and phosphatidylmethylethanolamine and phosphatidylcholine as the polar lipids. The genomic DNA G+C content was 39.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM-C158T was most closely related to Paraliobacillus ryukyuensis DSM 15140T (96.8 % similarity), and the two strains formed a distinct branch in the phylogenetic tree. The level of DNA-DNA relatedness between the two strains was 15.6 %. The combination of phylogenetic analysis, phenotypic characteristics, chemotaxonomic differences and DNA-DNA hybridization data supported the view that strain YIM-C158T represents a novel species of the genus Paraliobacillus, for which the name Paraliobacillus quinghaiensis sp. nov. is proposed. The type strain is YIM-C158T (=DSM 17857T=CGMCC 1.6333T).