Table 3

Susceptibilities of M. tuberculosis WT and Rv1258c, Rv1218c, Rv0849, and Rv3065 KO mutants to compounds in the presence and absence of efflux inhibitors

CompoundMIC (μg/ml) for M. tuberculosis strain:
WTKO1KO5KO6KO7
Pyrroles
    AZI-5330.030.0160.004–0.0080.008–0.0160.008
    AZI-533 + verapamil0.0080.0080.0040.0040.004
    AZI-533 + PAβN0.0160.0040.0040.0040.002
    AZI-5300.250.1250.030.060.03
    AZI-530 + verapamil0.060.060.030.030.016
    AZI-530 + PAβN0.1250.030.030.060.016
Pyrazolones
    AZI-219256128–25664–128128–256128–256
    AZI-219 + verapamil16–3216–328–168–1616–32
    AZI-219 + PAβN32323212816-32
    AZI-335110.50.50.5–1
    AZI-335 + verapamil0.50.50.250.250.25
    AZI-335 + PAβN0.50.50.1250.25-0.50.5
Other drugs
    Clofazimine0.125–0.250.06–0.1250.06–0.1250.06–0.1250.03–0.06
    Clofazimine + verapamil0.030.030.0160.016–0.030.008–0.016
    Clofazimine + PAβN0.0160.030.0160.060.016
Efflux inhibitors
    Verapamil>200>200>200>200>200
    PAβN3216161616
  • MICs were determined by the resazurin-based microplate assay. Each reported value is the average of at least 2 independent assays. The efflux inhibitors verapamil and PAβN were added at 50 μg/ml and 4–8 μg/ml (subinhibitory) concentrations where required.