Prevalence of Colistin Resistance in in Eastern Turkey and Genomic Characterization of an Positive Strain from Retail Chicken Meat.

Colistin is one of the most effective antibiotics against multidrug resistant Gram-negative bacteria. However, the recent emergence of plasmid-borne mobilized colistin resistance () genes is considered a serious antimicrobial resistance challenge worldwide. In this study, we report detection of an carrying isolate (named ATAVET -1 Turkey) from retail raw chicken meat in Turkey. Of the 11 (from 500 total tested) phenotypically colistin-resistant isolates, 1 was shown to carry the gene by PCR. Whole-genome sequencing indicated that was located on a ∼13 kb-long contig that was almost identical to the corresponding part in pZJ1635, an IncI2 plasmid encoding in the same genetic context in another strain. In addition, ATAVET -1 Turkey harbored , , (A), (A), , (3″)-Ib, (6)-Id, and resistance genes. Phylogenetic analysis based on whole genome and multilocus sequence typing indicated that ATAVET -1 Turkey was more closely related to carrying isolates from food and human clinical samples previously reported from different parts of the world than to those from Turkey. These findings further emphasize the worldwide emergence and spread of meditated colistin resistance in bacteria with zoonotic potential within animals and the food chain.