Oceanisphaera pacifica sp. nov., isolated from the intestine of Trichiurus japonicus

A Gram-stain-negative, strictly aerobic, non-flagellated, oxidase- and catalase-positive, rod-shaped marine bacterium, designated strain DM8(T), was isolated from the intestine of Trichiurus japonicus in Weihai, China. The strain optimally grew at 25-35celcius, with 1.0-4.0% (w/v) NaCl and at pH 7.0-8.0. Its colonies were circular, slightly yellow, non-transparent, smooth, and approximately 0.8-1.5 mm in diameter, after being cultured for 48 h on marine agar 2216. Based on the result of phylogenetic analysis of 16S rRNA gene sequence, strain DM8(T) had close relationship with Oceanisphaera profunda SM1222(T) (96.9%) and the type strain DSM 15406( T) of the type species Oceanisphaera litoralis (94.7%), respectively. Genome sequencing revealed a genome size of 3,109,059 bp and a G + C content of 46.9 mol%. It had Q-8 as the sole respiratory quinone and possessed C-16:0, summed features 3 (C-16:1 omega 7c/C-16:1 omega 6c) and summed features 8 (C-18:1 omega 7c/C-18:1 omega 6c) as major fatty acids. The major polar lipid profile was composed of phosphatidylglycerol and phosphatidylethanolamine. Based on the phenotypic, chemotaxonomic characterizations, phylogenetic properties and genome analysis, strain DM8(T) should represent a novel species of the genus Oceanisphaera, for which the name Oceanisphaera pacifica sp. nov. is proposed. The type strain is DM8(T) (= KCTC 82764( T) = MCCC 1K06133(T)).

Automated summary

This article describes a novel marine bacterium, Oceanisphaera pacifica sp. nov., isolated from the intestine of Trichiurus japonicus in Weihai, China. Through morphological, biochemical, genetic sequencing, and genome analysis, it has been confirmed as a new species of the genus Oceanisphaera.