Analysis of the fitness cost of five CTX-M-plasmids (IncF and IncA/C type) in J53-2 E. coli strain, using in vitro experimental evolution and whole genomic sequencing

We compared the fitness cost of three narrow-range F-type plasmids, including the IncF plasmid of RST F2:A1:B- suited to E. coli O25b:H4 ST131 H30Rx/C2 pandemic sublineage, and of two broad-range A/C-type plasmids, carrying a blaCTX-M-15 or a blaCTX-M-14 gene, in the K-12-like J53-2 E. coli strain. We analysed the impact of these plasmids, immediatly after conjugation, and after an evolution experiment at 1,120 generations, for CTX-M-15 plasmids. Using whole genome sequencing, we described chromosomal and plasmid mutational events detected for all ancestral and evolved transconjugants

本研究以类K-12型J53-2大肠杆菌（E. coli）菌株为宿主，对比了3种窄宿主范围F型质粒与2种宽宿主范围A/C型质粒的适合度成本；其中3种F型质粒包含适配大肠杆菌O25b:H4 ST131 H30Rx/C2流行亚谱系的RST F2:A1:B-型IncF质粒，2种A/C型质粒分别携带blaCTX-M-15与blaCTX-M-14耐药基因。针对携带blaCTX-M-15的质粒，我们分别分析了其在细菌接合完成后即刻，以及历经1120代进化实验后的宿主适配影响。借助全基因组测序(Whole Genome Sequencing)技术，我们对所有祖先型及进化后接合子的染色体与质粒突变事件进行了系统表征与分析。