FIG 4.

Mutations found in resistance-conferring regions of gyrA, parC, and gyrB in 2 enrofloxacin-resistant E. coli replicates cultured for 30 days in the presence or absence of the antibiotic. Blue indicates mutations in gyrA; red, mutations in parC; grey, mutations in gyrB. The asterisks indicate mutations found in only one of the two colonies that were sequenced for each data point.