Polaribacter tangerinus sp. nov., isolated from sediment in a sea cucumber culture pond.

A Gram-stain-negative, aerobic, non-motile, coccoid, ovoid or rod-shaped, and orange-pigmented bacterial strain, designated WS2-14, was isolated from sediment collected from a sea cucumber culture pond located in Rongcheng, Shandong province, PR China (122° 14' E, 36° 54' N). Strain WS2-14 grew optimally at 28 °C and pH 7.0-7.5, and was able to tolerate salt concentrations of 0.5-6.0 % (w/v) NaCl. Strain WS2-14 was characterized chemotaxonomically as possessing menaquinone-6 (MK-6) as the major respiratory quinone, as well as iso-C13 : 0, iso-C15 : 0 3-OH and iso-C15 : 0 as the predominant fatty acids. The DNA G+C content of strain WS2-14 was 31.2 mol%. The major polar lipids were phosphatidylethanolamine, one unidentified phospholipid, one unidentified aminolipid and three unidentified lipids. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain WS2-14 was phylogenetically related to members of the genus Polaribacter and was closely related to Polaribacter haliotis, Polaribacter atrinae and Polaribacter sejongensis with 97.7, 97.4 and 97.0 % sequence similarities, respectively. On the basis of its phenotypic and chemotaxonomic properties, as well as phylogenetic analyses, strain WS2-14 was considered to represent a novel species of the genus Polaribacter, for which the name Polaribactertangerinus sp. nov. is proposed. The type strain is WS2-14 (=KCTC 52275=MCCC 1H00163).