Vibrio ostreae sp. nov., a novel gut bacterium isolated from a Yellow Sea oyster

A Gram-stain-negative, oxidase- and catalase-positive, facultative anaerobic motile bacterium, designated strain OG9-811T, was isolated from the gut of an oyster collected in the Yellow Sea, Republic of Korea. The strain grew at 10-37 degrees C, pH 6.0-9.0 and with 0.5-10% (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain OG9-811T affiliated with the genus Vibrio, with the highest sequence similarity of 98.2% to Vibrio coralliilyticus ATCC BAA-450T followed by Vibrio variabilis R-40492T (98.0%), Vibrio hepatarius LMG 20362T (97.7%) and Vibrio neptunius LMG 20536T (97.6%); other relatives were Vibrio tritonius JCM 16456T (97.4 %), Vibrio fluvialis NBRC 103150T (97.0%) and Vibrio furnissii CIP 102972T (97.0%). The complete genome of strain OG9-811T comprised two chromosomes of a total 4807 684 bp and the G+C content was 50.2 %. Results of analysis based on the whole genome sequence showed the distinctiveness of strain OG9-811T. The average nucleotide identity (ANI) values between strain OG9-811T and the closest strains V. coralliilyticus ATCC BAA-450T, V. variabilis R-40492T, V. hepatarius LMG 20362T, V. neptunius KCTC 12702T, V. tritonius JCM 16456T, V. fluvialis ATCC 33809T and V. furnissi CIP 102972T were 73.0, 72.6, 73.3, 73.0, 72.7, 78.5 and 77.8%, respectively, while the digital DNA-DNA hybridization values between strain OG9-811T and the above closely related strains were 20.8, 21.2, 20.8, 21.7, 20.7, 23.2 and 22.4%, respectively. The major fatty acids of strain OG9-811T were summed feature 3 (C 16:1.7c and/or C 16:1.6c), summed feature 8 (C 18:1.6c and/or C 18:1.7c) and C 16:0. The polar lipids contained phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Strain OG9-811T contained Q-8 as a quinone. On the basis of polyphasic taxonomic characteristics, strain OG9-811T is considered to represent a novel species, for which the name Vibrio ostreae sp. nov. is proposed. The type strain is OG9-811T (=KCTC 72623T=GDMCC 1.2610T).

Automated summary

A new species of Gram-stain-negative facultative anaerobic motile bacterium, designated Vibrio ostreae sp. nov., was isolated from the gut of an oyster collected in the Yellow Sea, Republic of Korea. Phylogenetic analysis and whole genome sequencing revealed its distinctiveness from closely related strains in the genus Vibrio.