Advantage of the F2:A1:B- IncF Pandemic Plasmid over IncC Plasmids in <i>In Vitro</i> Acquisition and Evolution of <i>bla</i> _CTX-M Gene-Bearing Plasmids in Escherichia coli

Abstract

Despite a fitness cost imposed on bacterial hosts, large conjugative plasmids play a key role in the diffusion of resistance determinants, such as CTX-M extended-spectrum β-lactamases. Among the large conjugative plasmids, IncF plasmids are the most predominant group, and an F2:A1:B- IncF-type plasmid encoding a CTX-M-15 variant was recently described as being strongly associated with the emerging worldwide Escherichia coli sequence type 131 (ST131)-O25b:H4 H 30Rx/C2 sublineage.