Fig. 2.
Competition experiments during sub-MIC MTX exposure at different initial frequencies of TMPRstrains. The change in TMPR:TMPS ratios over 30 generations of growth at MTX concentrations slightly above the MSCs where E. coli MG1655 harbors (a) two folA mutations (MP18–07), and (b) the MDR pG06-VIM-1 plasmid (MP18–08) were competed against a differently tagged, isogenic susceptible strain (DA56507) at 1:1, 1:10−2, 1:10−3 and 1:10−4 starting ratios. Error bars represent the standard deviation of the average ratio, based on 6 individual replicates.