FIG 5 .

Deletion of mmcO had no effect on virulence. (A) Cu sensitivity assay (top) of WT and mmcO mutant strains in the H37Rv and CDC1551 backgrounds. We also complemented the mmcO mutation in the H37Rv background. This is representative of two independent experiments, each done in triplicate. At 150 µM, no CFU of the H37Rv strains were detected. Immunoblot analysis (bottom) of the same strains with polyclonal antibodies to MmcO. Antibodies to dihydrolipoamide acetyltransferase (DlaT) were used to show even loading of cell lysates. (B) Agar plate assay assessing the Cu sensitivity of the M. tuberculosis strains in panel A. Serial dilutions of M. tuberculosis cultures were spotted onto agar with the indicated CuSO₄ concentrations. Data are representative of two independent experiments. (C) CFU counts in the lungs and spleens of C57BL/6 mice infected with WT, mmcO, and mmcO-complemented (comp.) M. tuberculosis strain H37Rv. The results shown are for days 1 (n = 3), 21 (n = 4), and 56 (n = 4). ns, not significant. The data represent the mean ± SD of a typical experiment that was done twice.