Halomonas alkalisoli sp. nov., a novel haloalkalophilic species from saline-alkaline soil, and reclassification of Halomonas daqingensis Wu et al. 2008 as a later heterotypic synonym of Halomonas desiderata Berendes et al. 1996

Two Gram-stain-negative, strictly aerobic, moderately halophilic, non-spore-forming and rod-shaped bacteria, designated M5N1S17T and M5N1S15, were isolated from saline soil in Baotou, China. A phylogenetic analysis based on 16S rRNA gene sequences showed that the two strains clustered closely with Halomonas montanilacus PYC7WT and shared 99.1 and 99.3% sequence similarities, respectively. The average nucleotide identity based on BLAST (ANIb) and MUMmer (ANIm) values of the two strains with each other were 95.5% and 96.7%, respectively, while the ANIb and ANIm values between the two strains and 15 closer Halomonas species were 74.8–91.3% and 84.1–92.6%, respectively. The major polar lipids of M5N1S17T are diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, and an unidentified phospholipid. The major polar lipids of M5N1S15 are diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, two unidentified phospholipids, and an unidentified lipid. The predominant ubiquinone in the two strains is Q-9. The major fatty acids of the two strains are C18:1 ω6c and/or C18:1 ω7c, C16:0, and C16:1 ω7c and/or C16:1 ω6c. Based on phylogenetic, phenotypic, and physiological results, strains M5N1S17T and M5N1S15 should be identified as a novel species of the genus Halomonas, for which Halomonas alkalisoli sp. nov. is proposed. The type strain is M5N1S17T (= CGMCC 1.19023T = KCTC 92130T). The phylogenetic trees showed that Halomonas daqingensis CGMCC 1.6443T clustered tightly with Halomonas desiderata FB2T, and the two strains shared >98.0% of ANI values with each other. Therefore, we propose the reclassification of H. daqingensis Wu et al. 2008 as a later heterotypic synonym of H. desiderata Berendes et al. 1996.