Aquisalinus flavus gen. nov., sp. nov., a member of the family Parvularculaceae isolated from a saline lake

A Gram-stain-negative bacterium, strain D11M-2T, was isolated from a saline lake (Lake Dasugan) in Qaidam basin, Qinghai Province, China. Its taxonomic position was determined by using a polyphasic approach. Cells were non-spore-forming rods, 0.5-0.7 μm wide and 1.2-1.6 μm long, and motile by means of a single subpolar or lateral flagellum. Strain D11M-2T was strictly heterotrophic and aerobic, and catalase- and oxidase-positive. Growth was observed in the presence of 0-14.0% (w/v) NaCl (optimum, 2.0%), and at 10-35 °C (optimum, 30 °C) and pH 6.0-10.5 (optimum, pH 8.0). Strain D11M-2T contained Q-10 and Q-11 as the respiratory quinones and three unknown glycolipids as the major polar lipids. The major cellular fatty acids (>10.0%) were summed feature 8 (C18:1ω7c and/or C18:1ω6c) and C16:0. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain D11M-2T belonged to the family Parvularculaceae and formed a separate lineage that was independent of the two genera within the family Parvularculaceae. Strain D11M-2T exhibited 92.8-93.4% 16S rRNA gene sequence similarity to members of the genus Parvularcula (highest to Parvularcula bermudensis HTCC 2503T), and 90.2% to a member of the genus Amphiplicatus. The DNA G+C content was 59 mol% (Tm). Based on the phenotypic, chemotaxonomic and phylogenetic data, strain D11M-2T is considered to represent a novel species of a new genus in the family Parvularculaceae, for which the name Aquisalinus flavus gen. nov., sp. nov. is proposed. The type strain of Aquisalinus flavus is D11M-2T (=CGMCC 1.12921T=KCTC 42673T).