N-Acetyl-S-farnesyl-L-cysteine (AFC)

N-Acetyl-S-farnesyl-L-cysteine is a synthetically derivatized cysteine amino acid inhibitor of S-farnesylcysteine carboxyl methyltransferase enzymes. These enzymes recognize N-Acetyl-S-farnesyl-L-cysteine as a substrate through the farnesyl moiety, and occupation of the binding site blocks processing of farnesylated proteins by the enzyme. Carboxyl methylation of farnesylated proteins is an important modification that regulates protein function. Blockade of methyltransferase processing of platelet rap1 proteins by N-Acetyl-S-farnesyl-L-cysteine leads to inhibition of platelet aggregation. N-Acetyl-S-farnesyl-L-cysteine is also described to block the cellular movement and membrane adhesion of Ras proteins by interfering with carboxyl methylation processing. N-Acetyl-S-farnesyl-L-cysteine as a substrate for isoprenylated protein methyltransferase is described to block fMet-Leu-Phe-stimulated release of superoxide radical anion in neutrophil cells. Inhibition of neutrophil chemotaxis by N-Acetyl-S-farnesyl-L-cysteine also produces suppression of inflammatory response induced by 12-O-tereadecanoyl-phorbol-13-acetate and arachidonic acid.