Characterization of a Escherichia coli strain that evolved in an experimental coevolution system

为了研究由宿主-寄生虫相互作用驱动的持续变化，我构建了一个由大肠杆菌和噬菌体Qb组成的协同进化模型。全基因组分析表明，大肠杆菌在实验进化中表现出比单一大肠杆菌更快的两个突变（traQ和csdA）的固定。杆菌野生型TraQ在部分抗性菌株中的过量表达。大肠杆菌引起TraA蛋白含量，包括propilin和pilin，和Qb扩增恢复到与在敏感菌株中观察到的水平相当。这些结果表明TraQ突变可能导致E.大肠杆菌群中，有少量具有F皮利的细胞支持噬菌体群，而大量无F皮利的细胞支持大肠杆菌群。大肠杆菌群。

To examine the ongoing changes driven by host-parasite interactions, I have constructed a coevolution model consisting of Escherichia coli and the bacteriophage Qb. Whole genome analysis indicated that E.coli showed fixation of two mutations (in traQ anc csdA) faster than in sole E.coli experimental evolution.To elucidate the mechanism underlying this coexistence, I investigated how a mutation in TraQ changed the physiological state of E. coli. Overexpression of wild-type TraQ in the partially resistant strain of E. coli caused both TraA protein content, including propilin and pilin, and Qb amplification to recover to levels comparable with observed in the susceptible strain. These results suggest the possibility that the mutation in TraQ may cause heterogeneity within the E. coli population, with a small number of cells with F pili supporting the phage population and a large number of cells without F pili supporting the E. coli population.