Halomonas tibetensis sp nov., isolated from saline lakes on Tibetan Plateau

Strains pyc13(T) and ZGT13 were isolated from Lake Pengyan and Lake Zigetang on Tibetan Plateau, respectively. Both strains were Gram-negative, catalase- and oxidase-positive, aerobic, rod-shaped, nonmotile, and nonflagellated bacteria. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains pyc13(T) and ZGT13 belong to the genus Halomonas, with Halomonas alkalicola 56-L4-10aEn(T) as their closest neighbor, showing 97.4% 16S rRNA gene sequence similarity. The predominant respiratory quinone of both strains was Q-9, with Q-8 as a minor component. The major fatty acids of both strains were C-18:1 omega 6c/C-18:1 omega 7c, C-16:1 omega 6c/C-16:1 omega 7c, C-16:0, and C-12:0 3OH. The polar lipids of both strains consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, glycolipid, phospholipids of unknown structure containing glucosamine, and unidentified phospholipids. The DNA G + C content of pyc13(T) and ZGT13 were 62.6 and 63.4 mol%, respectively. The DNA-DNA hybridization values of strain pyc13(T) were 34, 41, 61, 35, and 35% with the reference strains H. alkalicola 56-L4-10aEn(T), H. sediminicola CPS11(T), H. mongoliensis Z-7009(T), H. ventosae Al12(T), and H. fontilapidosi 5CR(T), respectively. Phenotypic, biochemical, genotypic, and DNA-DNA hybridization data showed that strains pyc13(T) and ZGT13 represent a new species within the genus Halomonas, for which the name H. tibetensis sp. nov. is proposed. The type strain is pyc13(T) (= CGMCC 1.15949(T) = KCTC 52660(T)).