Escherichia coli strain:M19736 Genome sequencing. Escherichia coli strain:M19736

In the present study, we wonder about the ability of E. coli M19736 clinical strain belonging to sporadic clone ST615 that was one of the first isolates harboring the mcr-1 gene in Latin America , to adapt to XDR phenotype by conjugation and transformation assays. The conservation along time of ARG in evolved MDR and XDR-E. coli M19736 strains showed different patterns of maintenance as well as variability in the capacity to transfer in turn the acquired conjugative plasmids including co-transfer of different plasmids. In addition, we identified EV in the native and in the evolved XDR-E. coli M19736 strains with crucial content for the competence of Antimicrobial resistance in the nosocomial niche, including the blaCTX-M-15 gene though the pDCAG1-CTX-M-15 was previously lost. As a whole, this scenario reveals the relevant role of sporadic clones as common vectors for the dissemination of acquired antimicrobial resistance within the framework of the HGT processes.