Greater Invasion and Persistence of mcr-1- Bearing Plasmids in Escherichia coli than in Klebsiella pneumoniae

As infections caused by multidrug-resistant “superbugs” are increasing globally, polymyxins are often the only viable therapeutic option. Alarmingly, the wide spread of the plasmid-mediated polymyxin resistance gene mcr-1 is restricting the clinical utility of this last-line treatment option.