Muricauda abyssi sp. nov., a marine bacterium isolated from deep seawater of the Mariana Trench

A Gram-stain-negative, non-motile and rod-shaped bacterium, designated as strain W52T, was isolated from deep seawater of the Mariana Trench and characterized phylogenetically and phenotypically. The strain could grow at 10-47 degrees C (optimum 32 degrees C), at pH 5.0-8.0 (optimum 6.0) and with 0-9% NaCl (optimum 3%, w/v). The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that W52(T) was related to members of the genus Muricauda and shared the highest identity with Muricauda oceani 501str8(T) (99.0%), followed by Muricauda aquimarina JCM 11811(T), Muricauda ruestringensis DSM 13258(T), Muricauda oceanensis 40DY170(T), Muricauda beolgyonensis KCTC 23501(T) and Muricauda zhangzhouensis 12C25(T) with 97.0-98.8% sequence similarity. 16S rRNA gene sequence identities between W52(T) and other members of the genus Muricauda were below 97.0 %. The major respiratory quinone was MK-6. The polar lipids were phosphatidylethanolamine (PE), one unidentified aminolipid and three unidentified lipids. The strain had iso-C-15:0, iso-C-17:0 3-OH and iso-C(15:1)G as the major fatty acids. The G+C content of the genomic DNA was 41.7 %. The combined genotypic and phenotypic data indicated that strain W52(T) represents a novel species of the genus Muricauda, for which the name Muricauda abyssi sp. nov. is proposed, with the type strain W52(T) (=MCCC 1K05111(T)= KCTC 82315T).