Oceanirhabdus sediminicola gen. nov., sp. nov., an anaerobic bacterium isolated from sea sediment.

A novel anaerobic bacterium, designated NH-JN4(T) was isolated from a sediment sample collected in the South China Sea. Cells were Gram-stain-positive, spore-forming, peritrichous and rod-shaped (0.5-1.2×2.2-7 µm). The temperature and pH ranges for growth were 22-42 °C and pH 6.0-8.5. Optimal growth occurred at 34-38 °C and pH 6.5-7.0. The NaCl concentration range for growth was 0.5-6 % (w/v) with an optimum of 2.5 %. Catalase and oxidase were not produced. Substrates which could be utilized were peptone, tryptone, yeast extract, beef extract and glycine. Main fermentation products from PYG medium were formate, acetate, butyrate and ethanol. Strain NH-JN4(T) could utilize sodium sulfite as an electron acceptor. No respiratory quinone was detected. The predominant fatty acids were anteiso-C15 : 0, C16 : 0, iso-C15 : 0, anteiso-C17 : 0 and C16 : 0 DMA. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and glycolipids. The DNA G+C content was 35.8 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain NH-JN4(T) was a member of family Clostridiaceae, and was most closely related to Clostridium limosum ATCC 25620(T), Clostridium proteolyticum DSM 3090(T), Clostridium histolyticum ATCC 19401(T) and Clostridium tepidiprofundi SG 508(T), showing 94.0, 93.0, 92.9 and 92.3 % sequence similarity, respectively. On the basis of phenotypic, genotypic and chemotaxonomic properties, strain NH-JN4(T) represents a novel species of a new genus in the family Clostridiaceae, for which the name Oceanirhabdus sediminicola gen. nov., sp. nov. is proposed. The type strain of the type species is NH-JN4(T) ( = JCM 18501(T) = CCTCC AB 2013103(T) = KCTC 15322(T)).