FIGURE 1.

Effect of treatment of M. bovis BCG piniBAC-RFP with anti-mycobacterials on intrabacterial ATP level and iniBAC promoter activity. Exponentially growing M. bovis BCG piniBAC-RFP cultures were treated with cell wall inhibitors that interfere with mycolic acid synthesis (INH), arabinogalactan synthesis (EMB, BTZ043) or peptidoglycan synthesis (MEM), and with inhibitors of oxidative phosphorylation (BDQ, CCCP), cofactor synthesis (PAS, POA) and nucleic acid and protein synthesis (MXF, RIF, STR) at the MIC of the respective drugs for 24 h. Then ATP content was measured with the BacTiter-Glo^TM assay (“ATP,” gray bars, in relative light units, RLU). iniBAC promoter activity was measured by determining the fluorescence of the cultures (“piniBAC activity,” red circles, in relative fluorescence units, RFU). D0 and D1 show the RLU and RFU values at the start and the end of the experiment for drug free cultures. For abbreviations of drugs and their targets see Table 1. Experiments were carried out three times independently in duplicates. Mean values and standard deviations for one representative experiment are shown. The ATP content determinations were also carried out for M. bovis BCG not carrying the piniBAC-RFP reporter and found to be the same as the values obtained for M. bovis BCG piniBAC-RFP.