Oceanobacillus pacificus sp. nov., isolated from a deep-sea sediment

Abstract

A moderately halophilic bacterial strain, designated XH204T, was isolated from deep-sea sediment core (45° 58′ S 163° 11′ W) of the South Pacific Gyre during the Integrated Ocean Drilling Program Expedition 329. The strain was Gram-stain-positive, rod-shaped, motile by peritrichous flagella and produced ellipsoidal endospores subterminally positioned within swollen sporangia. Growth of strain XH204T occurred at 15–42 °C (optimum 37 °C), in the presence of 0–14 % (w/v) NaCl (optimum 4 %) and at pH 7.0–10.0 (optimum pH 8.0). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain XH204T belonged to the genus Oceanobacillus and showed the highest sequence similarity to Oceanobacillus profundus CL-MP28T (95.6 %); strain XH204T exhibited 93.4 % 16S rRNA gene sequence similarity to the type strain of the type species of the genus Oceanobacillus , Oceanobacillus iheyensis HTE831T. The dominant fatty acids of strain XH204T were anteiso-C15 : 0, iso-C14 : 0 and iso-C16 : 0. The cell wall of strain XH204T contained meso-diaminopimelic acid as the diagnostic diamino acid, and ribose, glucose and galactose as the major whole-cell sugars. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. Menaquinone-7 (MK-7) was the only isoprenoid quinone and the DNA G+C content was 38.8 mol%. Based on the phenotypic, chemotaxonomic and phylogenetic analysis, strain XH204T represents a novel species of the genus Oceanobacillus , for which the name Oceanobacillus pacificus sp. nov. is proposed. The type strain is XH204T ( = DSM 25873T = JCM 18381T).