Fusion Event Mediated by IS903B between Chromosome and Plasmid in Two MCR-9- and KPC-2-Co-Producing Klebsiella pneumoniae Isolates

Herein, we first isolated two MCR-9- and KPC-2-co-producing K. pneumoniae isolates. Notably, we observed a fusion event between the chromosome and plasmid, mediated by IS903B, in these two strains. This cointegration of chromosomes and plasmids introduces a new mode of transmission for antimicrobial resistance genes.