Data from: Genetic variation for antibiotic persistence in Escherichia coli

Bacterial persistence describes a heterogenous response to antibiotics in clonal populations of bacteria due to phenotypic variation within the population, with a small proportion of cells surviving treatment even at very high concentrations of drug. The aim of this study was to determine whether different natural isolates of E. coli, selected at random from a collection representing the spectrum of genetic diversity in the species, generate different fractions of persister cells. Despite comparable minimum inhibitory concentrations (MICs) to the antibiotics between the different strains, highly significant variation was observed in persister fractions following exposure to ampicillin, streptomycin or norfloxacin. Survival following treatment with one drug did not, however, correlate with survival against another. Finally, using competition assays we quantify fitness benefits of persistence. These results show that different strains of E. coli vary markedly in their response to antibiotics despite comparable genetic susceptibility and indicate different mechanisms of evolved persistence to different antibiotics.细菌持久性（Bacterial persistence）指细菌克隆种群中，因种群内表型变异而对抗生素产生的异质性应答：即便是在极高药物浓度下，仍有极小比例的细菌细胞可在抗生素处理中存活。本研究旨在探究：从涵盖该物种全部遗传多样性的菌株库中随机选取的不同大肠杆菌（E. coli）自然分离株，是否会产生不同比例的持留菌（persister cells）。尽管不同菌株对抗生素的最低抑菌浓度（minimum inhibitory concentrations, MICs）相当，但在暴露于氨苄青霉素、链霉素或诺氟沙星后，持留菌比例却呈现出极显著的差异。然而，经一种药物处理后的存活率，与经另一种药物处理后的存活率并无关联。最后，本研究通过竞争测定法量化了持留性带来的适合度收益。上述结果表明，尽管不同大肠杆菌菌株的遗传易感性相当，但其对抗生素的应答却存在显著差异，同时也提示针对不同抗生素的进化性持留机制存在差异。