Table 5.

KatG peroxidase activity of the ndhmutant strains

Relevant genotypeaINH resistance (MIC, μg/ml)bKatG peroxidase activityc
ndh + 51
ndh-14 >1000.5
ndh-15 >1000.7
ndh-21 >1000.9
ndh-29 >1001.4
ndh-4/pMV261::ndh (M. tuberculosis)2.51.1
ndh-4/pMV261::mdh (M. bovisBCG)10.4
  • a All strains are derived from the INHs parent strain mc2155 (Table 1).

  • b These data are from Tables 3 and 4.

  • c KatG activity was measured as the rate ofo-dianisidine oxidation in the presence of H2O2 as described in Materials and Methods. All assays were repeated three times with the same extracts; in all cases, error was less than 10%. All activities are expressed relative to that of the ndh + control, strain mc2155 or mc21421; the assays were performed in parallel.