Novel chromosomal insertions of ISEcp1-bla and diverse antimicrobial resistance genes in Zambian clinical isolates of Enterobacter cloacae and Escherichia coli.

Background: The epidemiology of extended-spectrum β-lactamases (ESBLs) has undergone dramatic changes, with CTX-M-type enzymes prevailing over other types. bla genes, encoding CTX-M-type ESBLs, are usually found on plasmids, but chromosomal location is becoming common. Given that bla-harboring strains often exhibit multidrug resistance (MDR), it is important to investigate the association between chromosomally integrated bla and the presence of additional antimicrobial resistance (AMR) genes, and to identify other relevant genetic elements.