Mesohalobacter salilacus sp. nov., a novel halotolerant, flexirubin-type pigment-producing bacterium of the family Flavobacteriaceae

A Gram-staining-negative, non-motile, aerobic, rod-shaped bacterium, designated 14752^T, was isolated from a saline lake in Xinjiang Uygur Autonomous Region, China. The strain was subjected to a taxonomic study using a polyphasic approach. Strain 14752^T was able to grow at 4-40 ℃ (optimum 28 ℃), pH 6.0-7.5 (optimum 7.0) and with 1.0-9.0% NaCl (optimum 3-4%, w/v). Phylogenetic and sequence similarity analysis of 16S rRNA gene sequences indicated that strain 14752^T was grouped with <i>Mesohalobacter halotolerans</i> WDS2C27^T, with the highest similarity of 98.13%. In comparison, this similarity between strain 14752^T and other valid published species was less than 92%. The average nucleotide identity based on blast alignments, digital DNA-DNA hybridization and average amino identity values between strain 14752^T and <i>M. halotolerans</i> WDS2C27^T were 80.13%, 22.60% and 83.91%, respectively. Chemotaxonomic analysis showed that the sole respiratory quinone was menaquinone 6 (MK-6), the major fatty acids included anteiso-C_15:0, iso-C_15:0 and iso-C_15:1 G. The major polar lipids included phosphatidylethanolamine, two uncharacterized aminolipids, one uncharacterized amino phospholipid, one uncharacterized phospholipid and one uncharacterized lipid. The genomic DNA G+C content of the strain 14752^T was 34.1 mol%. According to the physiological, genotypic, genomic and chemotaxonomic features revealed in this investigation, it is recommended that strain 14752^T represents a novel species of the genus <i>Mesohalobacter</i>, for which the name <i>Mesohalobacter salilacus</i> sp. nov. is proposed. The type strain is 14752^T (=KCTC 72044^T=MCCC 1K03765^T).