Virgibacillus zhanjiangensis sp. nov., a marine bacterium isolated from sea water

Abstract

A Gram-positive, endospore-forming, catalase- and oxidase-positive, motile, rod-shaped, aerobic bacterium, designated strain JSM 079157(T), was isolated from surface seawater off the coastline of Naozhou Island in South China Sea. The organism was able to grow with 1-15% (w/v) total salts (optimum, 4-7%), and at pH 6.0-10.0 (optimum, pH 7.5) and 10-45 degrees C (optimum, 30 degrees C). meso-Diaminopimelic acid was present in the cell-wall peptidoglycan. The predominant menaquinone was MK-7, and the polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The major cellular fatty acids were anteiso-C(15:0) (45.1%) and anteiso-C(17:0) (16.2%), and the DNA G + C content was 39.5 mol%. A phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain JSM 079157(T) should be assigned to the genus Virgibacillus, being related most closely to the type strains of Virgibacillus litoralis (97.4% sequence similarity), Virgibacillus necropolis (97.3%) and Virgibacillus carmonensis (97.1%). These four strains formed a distinct subcluster in the phylogenetic tree. The levels of DNA-DNA relatedness between the new isolate and the type strains of V. litoralis, V. necropolis and V. carmonensis were 30.4, 19.3 and 12.6%, respectively. The results of the phylogenetic analysis, combined with DNA-DNA relatedness data, phenotypic characteristics and chemotaxonomic information, support the suggestion that strain JSM 079157(T) represents a new species of the genus Virgibacillus, for which the name Virgibacillus zhanjiangensis sp. nov. is proposed. The type strain is JSM 079157(T) (=DSM 21084(T) = KCTC 13227(T)).