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

A novel aerobic bacterium designated DX6 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 pH 5.0-10.0 (optimum pH 7.0-9.0). Phylogenetic analysis of the 16S rRNA gene sequences indicated that strain DX6 formed a distinct lineage in the clade of genus Halomonas and is related to Halomonas desiderata DSM 9502 (98.3%), Halomonas kenyensis AIR-2 (97.7%), Halomonas daqingensis DQD2-30 (97.6%), Halomonas saliphila LCB169 (97.4%) and Halomonas endophytica MC28 (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 DX6 and the related type Halomonas strains further revealed that strain DX6 represented a distinct species. The main respiratory quinones of strain DX6 were ubiquinone 9 (Q-9) and ubiquinone 8 (Q-8). The predominant cellular fatty acids were summed feature 8 (Cω7c and/or Cω6c), summed feature 3 (Cω7c and/or Cω6c) and C. 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 DX6 represents a novel species of the genus Halomonas. The name Halomonas bachuensis sp. nov. is proposed with strain DX6 (= CCTCC AB 2020094 = KCTC 82196) designated as the type strain.