FIG 2.

(a to f) Population dynamics of the experimental evolution of ciprofloxacin resistance in E. coli (a, b), A. baumannii (c, d), and P. aeruginosa (e, f). The frequency of major mutations (reaching ≥5%) in evolving bacterial populations is shown as a function of time for selected reactors. The results of selected reactors are shown, as follows: reactor 4 from CEC-2 (a); reactor 5 from CEC-4 (b); reactor 5 from CAB (c); reactor 6 from CAB (d); reactor 5 from PAC-1 (e); and reactor 6 from PAC-2 (f).