SubMIC selective window is wider than the traditional window. The difference in growth fitness between a susceptible (blue line) and an isogenic
resistant mutant (red line) is plotted as a function of antibiotic concentration. For the ciprofloxacin-resistant mutant (gyrA Ser83Leu) the subMIC
selective window in which the mutant strain has a growth advantage extends over a 230-fold concentration range, from 0.1 ng/mL (the minimal
selective concentration, MSC, of the mutant) to 23 ng/mL (the minimal inhibitory concentration of the wild-type, MICsusc). By contrast, the traditional
selective window in which only the mutant grows extends over a 17-fold concentration range from 23 ng/mL to 380 ng/mL, MICres (the minimal
concentration of drug that inhibits this mutant strain).
Figure is modified from PLoS Pathogens