Two novel species of the family Bacillaceae: Oceanobacillus piezotolerans sp. nov. and Bacillus piezotolerans sp. nov., from deep-sea sediment samples of Yap Trench

Two novel strains, designated YLB-02 T and YLB-04 T , were isolated from the deep-sea sediments of Yap Trench located in the Pacific Ocean. Cells of the strains were Gram-stain-positive, oxidase- and catalase-positive and rod-shaped. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain YLB-02 T belonged to the genus Oceanobacillus and strain YLB-04 T belonged to the genus Bacillus . Strain YLB-02 T showed similarities of 96.9 % with Ornithinibacillus contaminans CCUG 53201 T , 96.3 % with Oceanobacillus profundus CL-MP28 T , 96.1 % with Oceanobacillus halophilus J8B T and 95.7 % with Oceanobacillus bengalensis Ma-21 T . Strain YLB-04 T showed the highest sequence similarity of 97.4 % with Bacillus notoginsengisoli SYP-B691 T . The average nucleotide identity (ANI) and the DNA-DNA hybridisation (DDH) estimate values for strain YLB-02 T and YLB-04 T with their related type strains were below the respective threshold for species differentiation. The G+C contents of strains YLB-02 T and YLB-04 T were 37.3 and 45.4 mol%. The predominant (>10 %) cellular fatty acids of strain YLB-02 T were iso-C 14 : 0 , iso-C 15 : 0 , iso-C 16 : 0 and C 16 : 1 ω7 c alcohol, and those of strain YLB-04 T were C 16 : 0 , iso-C 15 : 0 , anteiso-C 15 : 0 and C 18 : 0 . Their predominant ubiquinone was MK-7. The cell-wall peptidoglycan of strain YLB-02 T contained glutamic acid, alanine, aspartic acid, lysine and ornithine, but no meso -diaminopimelic acid, while strain YLB-04 T contained meso -diaminopimelic acid, glutamic acid, alanine, aspartic acid, lysine and ornithine. In addition to diphosphatidylglycerol (DPG) and phosphatidylglycerol (PG), the polar lipids of strain YLB-02 T also consisted of an unidentified glycolipid (GL), two unidentified polar lipids (L1 and L2) and two unidentified phospholipids (PL1 and PL2), and those of strain YLB-04 T also consisted of phosphatidylethanolamine (PE) and an unidentified phospholipid (PL). Based on phenotypic, genotypic and chemotaxonomic characteristics, two novel species are proposed, Oceanobacillus piezotolerans sp. nov. with YLB-02 T (=MCCC 1A12699 T =JCM 32870 T ) and Bacillus piezotolerans sp. nov. with YLB-04 T (=MCCC 1A12711 T =JCM 32872 T ) as the type strains.