At the inner mitochondrial membrane (IM), calcium-independent phospholipase A2 gamma (PLA2G6) hydrolyzes, removing one of the acyl chains, cardiolipin (CL) to form monolysocardiolipin (MLCL). This reaction is inferred from rats. PLA2G6 has also been characterized in humans (Larsson et al. 1998, Ma et al. 1999, Larsson Forsell et al. 1999).