Abstract

Strain PVT-9aT, a novel Gram-stain-negative, aerobic, non-spore-forming, motile-by-gliding and rod-shaped bacterium, was isolated from a skin lesion of Atlantic salmon (Salmo salar L.) during a tenacibaculosis outbreak that occurred in 2016 at a Chilean fish farm. Phylogenetic analysis based on 16S rRNA gene sequencing confirmed that strain PVT-9aT belonged to the genus Tenacibaculum, being related to the closest type strains Tenacibaculum haliotis KCTC 52419T (98.49% sequence similarity), Tenacibaculum aestuariivivum JDTF-79T (97.36%), Tenacibaculum insulae JDTF-31T (97.29%) and Tenacibaculum ovolyticum IFO 15947T (97.15%). The genome size of strain PVT-9aT was 2.73 Mb with a DNA G+C content 31.09 mol%. Average nucleotide identity analysis among 30 Tenacibaculum species rendered the most similar strains as follows: T. haliotis KCTC 52419T (87.91%), T. ovolyticum IFO 15947T (82.47%), Tenacibaculum dicentrarchi 35/09T (81.08%), Tenacibaculum finnmarkense gv finnmarkense TNO006T (80.91%) and T. finnmarkense gv ulcerans TNO010T (80.96%). Menaquinone MK-6 was the predominant respiratory quinone. The predominant cell fatty acids (>10%) were iso-C15:0, iso-C15:1 G and iso-C15:0 3-OH. Phenotypic, chemotaxonomic and genomic data supported the assignment of strain PVT-9aT (=DSM 115155T=RGM 3472T) as representing a novel species of Tenacibaculum, for which the name Tenacibaculum bernardetii sp. nov. is proposed. © 2023 The Authors.