First report of mcr-1 in Gulf region and a molecular description of the isolates and plasmids related to the gene. First report of colistin-resistant Escherichia coli carrying mcr-1 IncIX2 and IncX4 plasmids from camels in the Gulf Region.

To determine the phenotypic and genetic epidemiology of plasmid-mediated colistin resistance (mcr) in Escherichia coli obtained from camels in the Gulf Region (specifically the United Arab Emirates). Fifty fecal samples were collected from 50 camels at a Dubai-based farm in the UAE and colistin-resistant Gram-negative bacilli obtained using selective culture. A multiplex mcr-gene PCR, plasmid profiling and WGS were subsequently performed. Eleven of 50 camel feces (22%) yielded colonies positive for the mcr-1 gene. No other mcr-gene variant was detected. After plasmid profiling using gel electrophoresis and WGS, a selection of 9 Escherichia coli isolates from 8 camels were available for analysis.