Bacillus salinus sp. nov., isolated from commercial solar salt.

Abstract

Two strains of Gram-stain-positive, strictly aerobic, motile, spore-forming, rod-shaped, moderately halotolerant bacteria, designated as HMF5848T and HME7618, were isolated from salt/brine and subjected to a polyphasic taxonomic investigation. Growth of both yellow-coloured strains occurred in the presence of 1-9 % NaCl (w/v; optimum, 2-3 %), at 15-45 °C (optimum, 37 °C) and pH 6-9 (optimum, pH 7). The major fatty acids were iso-C15 : 0, iso-C16 : 0 and anteiso-C15 : 0. The cell-wall peptidoglycan was meso-diaminopimelic acid. The only respiratory quinone was menaquinone-7. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, four unidentified glycolipids, three unidentified phospholipids and two unidentified polar lipids. DNA G+C content was 37.4 mol%. Phylogenetic trees based on 16S rRNA gene sequences showed that strains HMF5848T and HME7618 clustered with Bacillus luteolus YIM 93174T. Strains HMF5848T showed the highest 16S rRNA gene sequence similarities to Bacillus humi LMG 22167T (96.1 %), Bacillus isabeliae CVS-8T (96.0 %) and Bacillus luteolus YIM 93174T (96.0 %). The values of in silico DNA-DNA hybridization and average nucleotide identity between strains HMF5848T and B. humi DSM 16318T were 25.8 and 69.7 %, respectively. On the basis of phylogenetic, physiological and chemotaxonomic properties, strain HMF5848T represents a novel species, Bacillus salinus sp. nov. The type strain is HMF5848T (=KCTC 43010T=CECT 9695T).