Alcanivorax profundimaris sp. nov., a Novel Marine Hydrocarbonoclastic Bacterium Isolated from Seawater and Deep-Sea Sediment

Two novel Alcanivorax -related strains, designated ST75FaO-1 T and 521-1, were isolated from the seawater of the South China Sea and the deep-sea sediment of the West Pacific Ocean, respectively. Both strains are Gram-stain-negative, rod-shaped, and non-motile, and grow at 10–40 °C, pH 5.0–10.0, in the presence of 1.0–15.0% ( w / v ) NaCl. Their 16S rRNA gene sequences showed 99.9% similarity. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that both strains belong to the genus Alcanivorax , and share 92.9–98.1% sequence similarity with all valid type strains of this genus, with the highest similarity being to type strain Alcanivorax venustensis DSM 13974 T (98.0–98.1%). Digital DNA–DNA hybridization (dDDH) and average nucleotide identity values between strains ST75FaO-1 T and 521-1 were 75.7% and 97.1%, respectively, while the corresponding values with A. venustensis DSM 13974 T were only 25.4–25.6% and 82.4–82.7%, respectively. The two strains contained similar major cellular fatty acids including C 16:0 , C 18:1 ω 7 c / ω 6 c , C 19:0 cyclo ω 8 c , C 16:1 ω 7 c / ω 6 c , C 12:0 3-OH, and C 12:0 . The genomic G + C content of strains ST75FaO-1 T and 521-1 were 66.3% and 66.1%, respectively. Phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, and one unidentified polar lipid were present in both strains. On the basis of phenotypic and genotypic characteristics, the two strains represent a novel species within the genus Alcanivorax , for which the name Alcanivorax profundimaris sp. nov. is proposed. The type strain is ST75FaO-1 T (= MCCC 1A17714 T = KCTC 82142 T ).