Azoarcus pumilus sp. nov., isolated from seawater in Sanya, China

A novel Gram-stain-negative, motile, rod-shaped (0.4–0.5×1.0–2.0 µm) strain with one polar flagellum, designated SY39T, was isolated from seawater in Sanya, China. Strain SY39T was able to grow at 15–40 °C (optimum, 35–37 °C), pH 6.5–8.5 (pH 8.0) and 0.5–6.0 % (w/v) NaCl (3.5 %). Chemotaxonomic analysis showed that the isoprenoid quinones were Q-8 (88.6 %) and Q-7 (11.4 %). The dominant fatty acids were C16 : 0 and summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c). The polar lipids of strain SY39T consisted of diphosphatidyglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unknown phosphoglycolipid, one unknown glycolipid and two unknown aminophosphoglycolipids. The DNA G+C content of the genomic DNA was 66.5 mol%. The phylogenetic analysis of 16S rRNA gene sequences showed that strain SY39T belongs to the genus Azoarcus with similarity ranging from 92.3 to 95.2 %. Based on the phenotypic, chemotaxonomic and phylogenetic features, strain SY39T is concluded to represent a novel species of the genus Azoarcus , for which the name Azoarcus pumilus sp. nov. is proposed. The type strain is SY39T (=KCTC 62157T=MCCC 1K03430T).