Extreme Antibiotic Persistence via Heterogeneity Generating Mutations Targeting Translation

Antibiotic persistence is the non-inherited tolerance of a sub-population of bacteria to high levels of antibiotics. It is thought to facilitate the rise of antibiotic resistance, and contribute to chronic infections in the clinic. Bacteria with increased persistence levels have been isolated from such chronic infections, suggesting that repeated exposures to antibiotics may lead to selection for hyper-persistent strains. However, the evolutionary trajectories that lead to such hyper-persistence, and the driving mutations have not been systematically characterized. Here, we show that evolution of hyper-persistence readily occurs in independent populations of Escherichia coli, and diverse mutations targeting translation drive this adaptation. We characterize the mutations present in the evolved populations. We also perform RNAseq on two distinct hyper-persister mutants, and on persister-enriched populations.