mitochondrial outer membrane
Mitochondrial amidoxime-reducing components 1 and 2 (MARC1 and 2) are Mo-molybdopterin (Mo-MPT) cofactor-dependent, outer mitochondrial membrane-associated enzymes capable of reducing N-hydroxylated prodrugs and N-hydroxy-L-arginine (NOHA) and N-hydroxy-N-methyl-L-arginine (NHAM) into L-arginine and N(delta)-methyl-L-arginine, respectively. They are components of an N-hydroxylated prodrug-converting complex, also containing cytochrome b5 (CYB5B) and NADH cytochrome b5 reductase 3 (CYB5R3) (Jakobs et al. 2014, Gruenewald et al. 2008, Ott et al. 2014, 2015). The reduction of NOHA is described in this reaction.