Deletion of pcnB affects antibiotic susceptibility in resistant Escherichia coli by reducing copy number of ColE1-family plasmids.

ABSTRACT: Plasmids play a major role in the spread of antibiotic resistance genes in bacteria. Plasmid copy number (PCN) is often tightly regulated. In plasmids of the ColE1-type, this regulation happens by a negative feedback mechanism using an antisense RNA. Here, we employed a sequencing-based method for determining PCN to demonstrate that copy number of different ColE1-family plasmids harboring antibiotic resistance genes increases during antibiotic treatment. Further, we show that deletion of the gene pcnB reduces the copy number of ColE1-family plasmids in E. coli MG1655, which in turn results in a reduced resistance to antimicrobials of the classes aminoglycosides, β-lactams and tetracyclines. In the absence of antibiotic selection, the deletion of pcnB also decreased the number of ColE1-type

SUBMITTER: Wellner SM 

PROVIDER: S-EPMC11897241 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature