aaX in which C is an S-isoprenylated cysteine residue, a is usually aliphatic and X is the C-terminal residue of the substrate protein, and may be any of several amino acids
Reaction: The peptide bond hydrolysed can be designated -CaaX in which C is an S-isoprenylated cysteine residue, a is usually aliphatic and X is the C-terminal residue of the substrate protein, and may be any of several amino acids
Comments: Type example of peptidase family M48. One of two enzymes that can catalyse this processing step for mating a-factor in yeast. Subsequently, the S-isoprenylated cysteine residue that forms the new C-terminus is methyl-esterified and forms a hydrophobic membrane-anchor.
Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 148463-92-7
References:
1. Tam, A., Schmidt, W.K. and Michaelis, S. The multispanning membrane protein Ste24p catalyzes CAAX proteolysis and NH2-terminal processing of the yeast a-factor precursor. J. Biol. Chem. 276 (2001) 46798-46806. [PMID: 11581258]