Pseudovibrio hongkongensis sp. nov., isolated from a marine flatworm

Abstract

A Gram-negative, motile, rod-shaped bacterial strain, designated UST20140214-015BT, was isolated from a marine flatworm (Polyclad). The bacterium was found to be Gram-negative, oxidase and catalase positive, long-rod shaped, and motile by means of several peritrichous or subpolar flagella. Strain UST20140214-015BT grew optimally at 28 °C, at pH 7.0 and in the presence of 3 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain UST20140214-015BT belongs to the genus Pseudovibrio, with highest sequence similarity to Pseudovibrio japonicus WSF2T (96.9 %), followed by P. ascidiaceicola F423T (96.7 %), P. denitrificans DN34T (96.6 %), P. axinellae Ad2T (96.3 %). All the other species shared <95.5 % sequence similarity. The principal fatty acids were identified as summed feature 8 (C18:1ω7c/ω6c, as defined by the MIDI system; 70.8 %), C16:0 (9.1 %), summed feature 3 (C16:1ω6c/C16:1ω7c; 5.7 %). The G+C content of the chromosomal DNA was determined to be 53.3 mol%. The combined genotypic and phenotypic data show that strain UST20140214-015BT represents a novel species within the genus Pseudovibrio, for which the name Pseudovibrio hongkongensis sp. nov. is proposed, with the type strain UST20140214-015BT (=KCTC 42383T = MCCC 1K00451T).