Roseovarius gahaiensis sp. nov., isolated from Gahai Saline Lake, PR China

A Gram-stain-negative, aerobic, non-motile and ovoid- to rod-shaped bacterial strain, designated GH877 T , was isolated from a water sample of Gahai saline lake in Qaidam Basin,PR China. The isolate grew at 5–45 °C, pH 6.0–9.0 (optima, 37 °C and pH 7.5) and with 0.5–20 % (w/v) NaCl (optimum, 2.0 %). The neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strain GH877 T belonged to the genus Roseovarius , and had highest 16S rRNA gene sequence similarity of 97.7 % to Roseovarius pacificus 81-2 T , followed by Roseovarius halotolerans HJ50 T (97.5 %) and Roseovarius litoreus GSW-M15 T (96.8 %). Genome sequencing revealed a genome size of 3 378 519 bp and a G+C content of 59.8 mol %. Up-to-date bacterial core gene set analysis indicated that strain GH877 T represents one independent lineage with R. pacificus DSM29589 T . The average nucleotide identity values of GH877 T with R. pacificus 81-2 T and R. halotolerans HJ50 T are 80.7 and 77.3 %, respectively. In silico DNA–DNA hybridization values between strain GH877 T and R. pacificus 81-2 T and R. halotolerans HJ50 T are 23.2 and 20.0 %, respectively. Q-10 was the predominant respiratory quinone and summed feature 8 (C 18  :  1 ω7 c and/or C 18  :  1 ω6 c ) and C 16  :  0 were the major cellular fatty acids. The polar lipids of strain GH877 T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and two unidentified phosphoglycolipids. Based on polyphasic taxonomic analysis, strain GH877 T is proposed to represent a novel species of the genus Roseovarius , for which the name Roseovarius gahaiensis sp. nov. is proposed. (type strain GH877 T =CGMCC 1.13971 T =KCTC 72576 T ).