Vibrio stylophorae sp. nov., isolated from the reef-building coral Stylophora pistillata

A bacterial strain designated KTW-12T was isolated from a reef-building coral in Kenting, Taiwan, and was characterized using a polyphasic taxonomic approach. Strain KTW-12T was Gram-negative, semi-transparent, slightly curved rod-shaped, and non-motile. Growth occurred at 15–35 °C (optimum, 30 °C), at pH 6.0–9.0 (optimum, pH 7.0–8.0), and with 0.5–6.0 % NaCl (optimum, 2 %). The major cellular fatty acids were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C14 : 0 and C16 : 0. The DNA G+C content was 47.8 mol%. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain KTW-12T was most closely related to Vibrio porteresiae MSSRF30T, with 94.8 % gene sequence similarity. Further multilocus sequence analysis using rpoA, recA and pyrH genes also revealed low levels of sequence similarity (74.6–85.0 %) with all species of the genus Vibrio with validly published names. A multigene phylogenetic tree using concatenated sequences of the four genes (16S rRNA, rpoA, recA and pyrH) elucidated that strain KTW-12T occupied a distinct phylogenetic position, forming a long branch that was not clustered with any other known species of the genus VIBRIO: Strain KTW-12T differed from V. porteresiae MSSRF30T in the ability to reduce nitrate to nitrite, hydrolysis of chitin, fermentation of sorbitol and production of arginine dihydrolase, valine arylamidase, cystine arylamidase and N-acetyl-β-glucosaminidase. On the basis of phenotypic, chemotaxonomic and phylogenetic distinctiveness, strain KTW-12T should be classified as representing a novel species, for which the name Vibrio stylophorae sp. nov. is proposed. The type strain is KTW-12T ( = BCRC 80105T = LMG 25357T).