Diversity of CTX-M-1-producing E. coli from German food samples and genetic diversity of the blaCTX-M-1 region on IncI1 ST3 plasmids

In conclusion, dissemination of the CTX-M-1 β-lactamase within food samples of animal origin is driven by the transmission of a ∼100 kb large IncI1 ST3 plasmid. Apart from conjugal transfer of IncI1 ST3 plasmids the transmission of the blaCTX-M-1 gene might be further promoted through mobilization due to its location within a recombination hot-spot of IncI1 plasmids.