A novel Gram-stain-negative bacterium, designated as SCSIO 06110T, was isolated from a deep-sea sediment of the West Pacific Ocean. Cells were 0.5-0.8 µm in width and 3.0-4.0 µm in length, spore-forming, rod-shaped with peritrichous flagella. Positive for catalase and urease, negative for oxidase and nitrate reduction. Growth occurred at 15-37 °C, pH 6-9 and 1-5 % (w/v) NaCl, with optimum growth at 28 °C, pH 7 and 3 % (w/v) NaCl. MK-7 was the only menaquinone. The strain possessed diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and two unidentified phospholipids. Iso-C16 : 0, iso-C15 : 0 and iso-C14 : 0 were the major fatty acids. The novel isolate clustered with genera in the family Paenibacillaceae, but formed a separated branch with the closest relative Chengkuizengella sediminis J15A17T (91.1 % sequence similarity) when compared in a phylogenetic analysis of 16S rRNA gene sequences. The DNA G+C content of strain SCSIO 06110T was 38.5 mol%. Based on the polyphasic data presented, a new genus, Longirhabdus gen. nov., is proposed in the family Paenibacillaceae with the type species Longirhabdus pacifica sp. nov. and the type strain SCSIO 06110T (=DSM 105158T=CGMCC 1.16550T).
Keywords: Longirhabdus pacifica gen. nov., sp. nov.; Paenibacillaceae; West Pacific Ocean; hydrothermal vent; polyphasic taxonomy.