Adaptive Evolution of Strains with AcrAB-TolC Efflux Pumps to Chloramphenicol

In this work, we evolved strains of Escherichia coli with different genotypes related to the AcrAB-TolC efflux pump. Parent strains were either wild type, had the pump overexpressed, or had the pump knocked out. We evolved these three strains under different levels of chloramphenicol. Each parent strain was evolved in an evolution experiment using three biological replicates. The most resistant isolate from each separate evolution experiment and the parent strains are provided here. The goal of this work was to identify which chloramphenicol concentrations promote the evolution of antibiotic resistance and how the presence of the AcrAB-TolC pump impacts this evolution.