Vibrio sinus sp. nov., a marine bacterium isolated from coastal seawater

A Gram-straining-negative, facultatively anaerobic, motile by means of a polar flagellum and rod-shaped marine bacterium, designated S4M6^T, was isolated from surface seawater collected in Dongshan Bay (Fujian, PR China). Phylogenetic analysis based on 16S rRNA genes, phylogenomic analysis of single-copy gene families and whole genome data indicated that S4M6^T represented a member of the genus Vibrio. The closest phylogenetic relatives of S4M6^T were Vibrio marisflavi CGMCC 1.8994^T (97.8 % 16S rRNA gene sequence pairwise similarity), Vibrio variabilis LMG 25438^T (96.9 %), Vibrio gangliei SZDIS-1^T (96.2 %) and Vibrio aestivus M22^T (96.1 %). The growth of S4M6^T occurred at 15-35 °C (optimum 28 °C), pH 4.0-9.0 (optimum 5.0-7.0) and in the presence of 2-5 % (w/v) NaCl (optimum 3 %). The predominant fatty acids (>10 %) are C_16 : 0, summed feature 3 (C_16 : 1ω7c and/or C_{16 :  1}ω6c) and summed feature 8 (C_18 : 1ω7c and/or C_{18 :  1}ω6c). The DNA G+C content of the assembled genomic sequences was 43.4 % for S4M6^T. Average nucleotide identity (ANI) values between S4M6^T and the reference species were lower than the threshold for species delineation (95-96 %); in silico DNA-DNA hybridization further indicated that S4M6^T had less than 70 % similarity to its relatives. On the basis of the polyphasic evidence, strain S4M6^T is proposed to represent a novel species of the genus Vibrio, for which the name Vibrio sinus sp. nov. is proposed. The type strain is S4M6^T (= KCTC 92312^T= MCCC 1K06167^T).