Figure 5.

Growth inhibition of M. tuberculosis strains by compound 3 or ciprofloxacin. Dose-dependent growth inhibition of M. tuberculosis strains H37Rv (black), M. tuberculosis 1192/015 (red), and M. tuberculosis 08/00483E (blue) by ciprofloxacin (0.094–6.036 μM) (A) and compound 3 (0.048–3.1 μM) (B). Twofold serial dilutions of each antibiotic were evaluated. The antibiotic activity was ascertained by the addition of resazurin, and the optical density (OD_570nm) was measured. The OD_570nm measurements were converted to a percentage of the OD_570nm measurements for the control that contained no antibiotic. The values plotted are a percentage of the growth without antibiotic and are the mean values of three independent experiments ± standard deviation and analyzed using Student’s t test. Vertical lines indicate modified Gompertz-determined MIC values.