English: FIGURE 1. Depiction of the putative mechanisms of action of clofazimine (CFZ) acting at the level of the mycobacterial cell membrane: (A) CFZ competes with menaquinone (MQ) as a substrate of type 2 NADH dehydrogenase (NDH-2) in the first step of the mycobacterial electron transport chain (ETC). This draws electrons away from the ETC, possibly reducing ATP production. Reduced CFZ produced in the process is spontaneously re-oxidized in the presence of intracellular oxygen (O2), leading to the formation of intracellular reactive oxygen species (ROS); (B) Clofazimine leads to an increase in lysophospholipids in a process mediated by phospholipase A2 (PLA2) activity. Lysophospholipids inhibit potassium (K+) uptake and cause direct membrane destabilisation, thereby also disrupting ATP production.