A Gram-stain-negative, non-motile bacterial strain, designated SW125T, was isolated from a deep-sea vsediment sample collected from the Indian Ocean. Cells were aerobic, catalase-positive and oxidase-positive. The strain grew at 4-42 °C (optimum, 30 °C), at pH 5.0-10.0 (optimum, pH 7.0-7.6) and in the presence of 0.5-9.0 % (w/v) NaCl (optimum, 2.0-3.0 %). Comparative analyses of the 16S rRNA gene sequence showed that strain SW125T was grouped in the vicinity of the genus Negadavirga with the highest sequence similarity of 91.6 % to the type strain of Negadavirga shengliensis. The quinone system contained menaquinone MK-7 as the predominant component. The predominant cellular fatty acids of strain SW125T were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). Strain SW125T contained phosphatidylethanolamine as the major polar lipid. The genomic DNA G+C content of strain SW125T was 43.2 mol%. On the basis of its phenotypic characteristics and phylogenetic data, strain SW125T represents a novel species of a new genus, for which the name Pleomorphovibrio marinus gen. nov., sp. nov. is proposed. The type strain is SW125T (=CGMCC 1.16172T=DSM 107180T=KCTC 62653T).
Keywords: Pleomorphovibrio marinus; deep-sea sediment; phylogenetic analysis.