Gracilibacillus saliphilus sp. nov., a moderately halophilic bacterium isolated from a salt lake

Abstract

A novel Gram-positive-staining, aerobic, spore-forming, rod-shaped bacterium, designated strain YIM 91119(T), was isolated from Ebinur Lake in Xinjiang Province, north-west China. Cells were motile, produced terminal endospores and grew at pH 6.0-8.0 (optimally at pH 7.0), 4-45 degrees C (optimally at 28-37 degrees C) and 1-22 % (w/v) NaCl, (optimally at 10-15 %, w/v). Comparative 16S rRNA gene sequence analysis showed that strain YIM 91119(T) belongs to the genus Gracilibacillus, exhibiting the highest sequence similarity with respect to the type strain of Gracilibacillus orientalis (97.8 %); the next most similar 16S rRNA gene sequences were those of the type strains of Gracilibacillus boraciitolerans (96.8 %), Gracilibacillus dipsosauri (96.5 %) and Gracilibacillus halotolerans (95.8 %). DNA-DNA hybridization with G. orientalis AS 1.4250(T) showed a relatedness of 55 %. The major fatty acids of strain YIM 91119(T) were anteiso-C(15 : 0), iso-C(15 : 0) and anteiso-C(17 : 0). The peptidoglycan type was A1gamma (directly cross-linked meso-diaminopimelic acid). The genomic DNA G+C content was 40.1 mol% and the predominant respiratory quinone was MK-7. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. On the basis of the evidence from this polyphasic study, strain YIM 91119(T) represents a novel species of the genus Gracilibacillus, for which the name Gracilibacillus saliphilus sp. nov. is proposed, with YIM 91119(T) (=DSM 19802(T) =CCTCC AA 208015(T)) as the type strain.