Oceaniglobus ichthyenteri sp. nov., isolated from the gut microflora of sea bass (Dicentrarchus labrax L.) and emended description of the genus Oceaniglobus

A Gram-stain-negative, non-flagellated, catalase-positive, oxidase-positive bacterial strain, designated YLY08 T , was isolated from the gut microflora of sea bass ( Dicentrarchus labrax L.) collected from the coast of Yuanyao Wharf, Weihai, PR China, and subjected to a polyphasic taxonomic study. Strain YLY08 T grew optimally at 28-30 °C, at pH 7.0-7.5 and in the presence of 2.0-3.0 % (w/v) NaCl. Poly- β -hydroxybutyrate granules were produced. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain YLY08 T clustered with the type strain of Oceaniglobus indicus , with which it exhibited 95.3 % sequence similarity, while the similarity to other genera was below 95.0 %. Genomic analyses, including average nucleotide identity and the digital DNA-DNA hybridization, clearly separated YLY08 T from O. indicus MCCC 1A11863 T with values below the thresholds for species delineation. The major cellular fatty acid was summed feature 8 (C 18 : 1 ω7 c and/or C 18 : 1 ω6 c ). The sole respiratory quinone detected was Q-10. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, phosphatidyldimethylethanolamine, diphosphatidylglycerol, one unidentified aminolipid and one unidentified phospholipid. The genome of strain YLY08 T , with 38 assembled contigs, was 3.9 Mb long with a G+C content of 59.0 mol%. The results of the phenotypical, phylogenetic and biochemical analyses between the strain YLY08 T and the related type strain indicated that this strain represents a novel species in genus Oceaniglobus within the family Rhodobacteraceae , for which the name Oceaniglobus ichthyenteri sp. nov. is proposed. The type strain is YLY08 T (=MCCC 1H00318 T =KCTC 62182 T ).