Flavobacterium psychraquaticum sp. nov., isolated from water system of Atlantic salmon (Salmo salar) smolts cultured in Chile

Strain LB-N7 T , a novel Gram-negative, orange, translucent, gliding, rod-shaped bacterium, was isolated from water samples collected from an open system of Atlantic salmon ( Salmo salar ) smolts in a fish farm in Chile during a flavobacterial infection outbreak in 2015. Phylogenetic analysis based on 16S rRNA sequences (1337 bp) revealed that strain LB-N7 T belongs to the genus Flavobacterium and is closely related to the type strains Flavobacterium ardleyense A2-1 T (98.8 %) and Flavobacterium cucumis R2A45-3 T (96.75 %). The genome size of strain LB-N7 T was 2.93 Mb with a DNA G+C content 32.6 mol%. Genome comparisons grouped strain LB-N7 T with Flavobacterium cheniae NJ-26 T , Flavobacterium odoriferum HXWNR29 T , Flavobacterium lacisediminis TH16-21 T and Flavobacterium celericrescens TWA-26 T . The calculated digital DNA–DNA hybridization values between strain LB-N7 T and the closest related Flavobacterium strains were 23.3 % and the average nucleotide identity values ranged from 71.52 to 79.39 %. Menaquinone MK-6 was the predominant respiratory quinone, followed by MK-7. The major fatty acids were iso-C 15 : 0 and anteiso-C 15 : 0 . The primary polar lipids detected included nine unidentified lipids, two amounts of aminopospholipid and phospholipids, and a smaller amount of aminolipid. Phenotypic, genomic, and chemotaxonomic data suggest that strain LB-N7 T (=CECT 30406 T =RGM 3221 T ) represents as a novel bacterial species, for which the name Flavobacterium psychraquaticum sp. nov. is proposed.