FIG 4.
Disulfiram is active on nonreplicating M. tuberculosis when copper ions are present. Disulfiram at 0.3 μM and copper at 10 μM kill actively replicating M. tuberculosis mc26230 after 3 days of incubation, with 12 μM rifampin (RIF) shown as the bactericidal control. Nonreplicating bacilli were generated by incubating bacteria in PBS for 8 weeks; they were then exposed to the same conditions as the replicating bacilli. While 0.3 μM disulfiram was unable to inhibit growth after 3 days, 2.5 μM disulfiram, when acting in concert with 10 μM copper, was able to completely kill M. tuberculosis.