Halomonas kashgarensis sp. nov., a Novel Species Isolated from the Rhizosphere Soil of Phragmites australis (Cav.) Trin. ex Steud in Kashgar County, Xinjiang, China

A novel Gram-negative, orange-colored, rod-shaped, oxidase and catalase-positive, non-spore-forming bacterium, designated as zp-37T, was isolated from the rhizosphere soil of Phragmites australis (Cav.) Trin. ex Steud in Kashgar County, Xinjiang, China. The phylogenetic analysis, based on the 16S rRNA genes, revealed that strain zp-37T belongs to the genus Halomonas. Growth of strain zp-37T was observed at 10–43 °C, pH 6.0–11.0, and 0–20% NaCl (w/v). The principal fatty acids of strain zp-37T were summed feature 8 (C18:1ω7c and/or C18:1ω6c, 55.67%) and summed feature 3 (C16:1ω7c and/or C16:1ω6c, 20.16%). The polar lipid profile contained diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), unidentified phospholipids (UPL 1–3), unidentified aminophospholipids (UAPL 1–2), and unidentified lipid (UL). Its main respiratory quinone was ubiquinone Q-9 (100%). The genome of strain zp-37T was 3,489,967 bp in size, containing two plasmids with lengths of 18,112 bp and 4364 bp, respectively. The genomic DNA G+C content of strain zp-37T was 59.3%. By the genome annotation, various genes related to the function of saline-alkaline stress tolerance and plant growth promotion were predicted. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between strain zp-37T and its five closely related strains were 72.64–75.59% and 19.70–20.40%, respectively, which were lower than the threshold for species delineation (ANI: 95–96%, dDDH: 70%). Based on the phylogenetic, phenotypic, and chemotaxonomic analyses and genomic comparisons, strain zp-37T was suggested to represent a novel species within the genus Halomonas, for which the name Halomonas kashgarensis sp. nov. is proposed. The strain type was designated zp-37T (=CGMCC 1.62213T = JCM 37305T).