Genome sequences of 28 tet(X4)-harboring Escherichia coli Isolated from Chickens in Pakistan

Here, we described the molecular epidemiology of tet(X4) and mcr-1 harboring E. coli strains isolated from chickens in Pakistan. The tet(X4) gene was identified in 36 isolates, and all of them exhibited high levels of tigecycline resistance (MICs, 16-128 mg/L). Worryingly, 24 of the 36 tet(X4)-bearing isolates were confirmed as colistin resistance, positive for plasmid-borne mcr-1 gene