Genomic evolution and stability of the mcr-1-harboring IncI2 plasmid in the presence and absence of colistin.

ABSTRACT:

Background

The emergence of plasmid-mediated colistin resistance, primarily driven by the mcr-1 gene, represents a major global health threat. IncI2 plasmids, one of the leading carriers of mcr-1, have been frequently recovered from clinical and agricultural settings. However, their persistence in the absence of antibiotic pressure and adaptive responses to colistin exposure remain poorly understood.

Methods

We conducted 60-day laboratory evolution experiments using Escherichia coli C600 carrying the mcr-1-harboring IncI2 plasmid pBD110 under three colistin concentrations (0, 2, and 4 mg/L). Stability was evaluated using polymerase chain reaction (PCR). Bacterial fitness was assessed using growth curve analysis and competition assays. Antimicrobial susceptibility was determi

SUBMITTER: Shen C 

PROVIDER: S-EPMC12750680 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature