Vibrio chanodichtyis sp. nov., isolated from the intestine of swordfish Chanodichthys dabryi

Abstract

A Gram-stain-negative, facultatively anaerobic, motile, curved-rod-shaped flagellated bacterium, designated DSL-7^T, was isolated from the intestine of Chanodichthys dabryi in the Yangtze river, PR China. The strain grew optimally in tryptone soy broth medium at 37 °C, pH 7.0 and with 1 % (w/v) NaCl. Strain DSL-7^T showed less than 96.2 % 16S rRNA gene sequence similarity to type strains of the genus Vibrio. Phylogenetic analysis based on genomes indicated that strain DSL-7^T belonged to the genus Vibrio and formed a subclade with Vibrio mimicus NCTC 11435^T, Vibrio metoecus OP3H^T, Vibrio cholerae ATCC 14035^T, Vibrio albensis ATCC14547^T, Vibrio paracholerae OP3HEDC-792^T and Vibrio tarriae 2521-89^T. The average nucleotide identity (ANI) and in digital DNA-DNA hybridization (dDDH) values between DSL-7^T and closely related type strains were below the accepted threshold to delineate a new species of 95 and 70 %, respectively. The major cellular fatty acids were summed feature 3 (C_{16 : 1} ω7c and/or C_{16 : 1} ω6c), C_{16 : 0}, summed feature 8 (C_{18 : 1} ω7c and/or C_{18 : 1} ω6c) and C_{14 : 0}. The genomic DNA G+C content was 47.6 mol%. Based on the phenotypic, chemotaxonomic, phylogenetic and genomic data, strain DSL-7^T represents a novel species of the genus Vibrio, for which the name Vibrio chanodichtyis sp. nov. is proposed, with strain DSL-7^T (=KCTC 92851^T=CCTCC AB 2022396^T) as the type strain.

Keywords: 16S rRNA gene; Chanodichthys dabryi; Vibrio chanodichtyis sp. nov.; digital DNA–DNA hybridization; polyphasic taxonomy.