Halomonas bachuensis sp. nov., Isolated from Gobi Soil.

Abstract

A novel aerobic bacterium designated DX6T was isolated from a Gobi soil sample collected in Bachu County, China. Cells are Gram-stain-negative and rod-shaped and colonies are creamy, circular and smooth. The growth range of NaCl concentration was 1-15% (optimum 2-10%, w/v). Growth occurs at 10-45°C (optimum 37°C) and pH5.0-10.0 (optimum pH7.0-9.0). Phylogenetic analysis of the 16S rRNA gene sequences indicated that strain DX6T formed a distinct lineage in the clade of genus Halomonas and is related to Halomonas desiderata DSM 9502T (98.3%), Halomonas kenyensis AIR-2T (97.7%), Halomonas daqingensis DQD2-30T (97.6%), Halomonas saliphila LCB169T (97.4%) and Halomonas endophytica MC28T (96.2%). Analysis of the housekeeping genes gryB and rpoD and calculation of the average nucleotide identities and the digital DNA-DNA hybridization values between strain DX6T and the related type Halomonas strains further revealed that strain DX6T represented a distinct species. The main respiratory quinones of strain DX6T were ubiquinone 9 (Q-9) and ubiquinone 8 (Q-8). The predominant cellular fatty acids were summed feature 8 (C18:1ω7c and/or C18:1ω6c), summed feature 3 (C16:1ω7c and/or C16:1ω6c) and C16:0. The major polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, an unidentified phosphatidylglycolipid, and four unidentified lipids. Based on the phenotypic, phylogenetic, chemotaxonomic and genomic features, strain DX6T represents a novel species of the genus Halomonas. The name Halomonas bachuensis sp. nov. is proposed with strain DX6T (= CCTCC AB 2020094T = KCTC 82196T) designated as the type strain.