Exilibacterium tricleocarpae gen. nov., sp. nov., a marine bacterium from coralline algae Tricleocarpa sp.

A Gram-stain-negative, non-spore-forming, aerobic, curved rod-shaped bacterium, designed strain R142 T , was isolated from a coralline algae Tricleocarpa sp. in the Beibu Gulf, China. Optimal growth occurred with 0–0.5 % (w/v) NaCl, at 25 °C and at pH 8. Global alignment based on 16S rRNA gene sequences indicated that strain R142 T shared 93.8 % similarity with its closest type strain, Pseudomaricurvus alkylphenolicus KU14G T . Phylogenetic analyses showed that strain R142 T forms a distinct branch alongside Maricurvus nonylphenolicus KU41E T , Pseudoteredinibacter isoporae SW-11 T , Pseudomaricurvus alkylphenolicus KU14G T , Pseudomaricurvus alcaniphilus MEBiC06469 T and Aestuariicella hydrocarbonica SM-6 T . The major polar lipids of strain R142 T were phosphatidylethanolamine and phosphatidylglycerol. The primary cellular fatty acids were C 16 : 0 , C 16 : 1 ω7 c , C 18 : 1 ω7 c , C 18 : 0 and C 14 : 0 . The genome DNA G+C ratio was 56.4 mol%. The only detected respiratory quinone was ubiquinone 8. The low 16S rRNA gene sequence similarity and differences in cellular fatty acids readily distinguished strain R142 T from all validly published type strains. Strain R142 T is therefore suggested to represent a novel species of a new genus, for which the name Exilibacterium tricleocarpae gen. nov., sp. nov. is proposed. The type strain of Exilibacterium tricleocarpae is R142 T (=MCCC 1K03816 T =KCTC 72138 T ).