Oceanospirillum sediminis sp. nov., Isolated From Coastal Sediment in the Yellow Sea

A novel Gram-negative, motile, aerobic, spiral-shaped bacterium designated D5T, was isolated from a coastal sediment collected in the Yellow Sea. Optimal growth occurred at 30 °C, pH 7.0–8.0 and in the presence of 1–3% (w/v) NaCl. Strain D5T contained ubiquinone 8 (Q-8) as the predominant respiratory quinone. The major fatty acids (> 10%) were C16:0, C16:1ω7c/C16:1ω6c and C18:1w7c/C18:1w6c. The main polar lipids were phosphatidylglycerol and phosphatidylethanolamine. The draft genome is 5.6 Mb in length, and DNA G + C content is 47.2 mol%. 16S rRNA gene sequences showed that strain D5T is most closely related to Oceanospirillum beijerinckii NBRC 15445T (97.8%, sequence similarity). However, the digital DNA-DNA hybridization (dDDH) value and average nucleotide identity (ANI) between strain D5T and O. beijerinckii is only 27.8% and 77.1%. Phylogenetic trees based on 16S rRNA gene sequences and whole genomes all indicated that strain D5T formed a separate branch in the genus Oceanospirillum. Combined results of the polyphasic analyses suggested that strain D5T represents a novel species in the genus Oceanospirillum, for which the name Oceanospirillum sediminis sp. nov. is proposed. The type strain is D5T (= MCCC 1K06061T = KCTC 62987T).