AQUACULTURE, cilt.535, 2021 (SCI-Expanded)
Fish diseases caused by bacterial genera belonging to the family Flavobacteriaceae, especially Tenacibaculum, Flavobacterium, and Chryseobacterium, are responsible for losses in wild and farmed fish around the world. In the last decade, the genus Chryseobacterium has rapidly grown in parallel with numerous novel Chryseobacterium species described from systemic infections of fish. Members of the family Flavobacteriaceae, isolated from fish, the environment, and clinical samples, have been reported to show low susceptibility to a broad range of antimicrobials. In this study, seventy C. aquaticum strains were isolated from diseased salmonids in Turkey. The phylogenetic analysis of all C. aquaticum strains, together with the reference strains in GenBank, which were obtained from different sources, including fish, plants, soil, water, and other animals, was performed by 16S rRNA gene sequence analysis. The antimicrobial susceptibility of each C. aquaticum strain was determined by a minimum inhibitory concentration (MIC) test. The isolate with the highest level of antimicrobial resistance, strain C-174, underwent a more detailed whole-genome sequence analysis for virulence and antimicrobial resistance genes (AMR) genes, genome size, and guanine-cytosine (GC) content.