sp. nov., a bacterium isolated from the gill homogenate of the mussel in a cold seep.

A novel Gram-negative, oxidase- and catalase-positive, rod-shaped bacterium, designated strain KX21116, was isolated from the mussel collected from a cold seep field in the South China Sea. Strain KX21116 grew optimally at 28 °C, pH 6.0 with 3% (w/v) NaCl, under aerobic and microaerobic conditions. Its genome size was 3.16 Mb, with a G+C content of 28.4 mol%. The 16S rRNA sequences revealed that strain KX21116 was closely related to DSM 7299 (98.77% gene sequence similarity) and AR-13 (95.58%). Phylogenetic and phylogenomic analysis revealed that strain KX21116 clustered with the type species of the genus , with DSM 7299 as its nearest neighbour. The genomic average nucleotide identity (orthoANI) values between strain KX21116 and DSM 7299 were 92.74%, while the DNA-DNA hybridization (GGDC) values of the two strains were 48.8%. The predominant fatty acids are C, C c/C1 c and C c/C1 c. Based on a comparative analysis of phylogenetic, phylogenomic, phenotypic and chemotaxonomic characteristics, strain KX21116 represents a novel species of the genus , for which the name sp. nov. is proposed. The type strain is KX21116 (=MCCC 1K08505=KCTC 92900=JCM 35939).