IUBMB Enzyme Nomenclature


Accepted name: acylaminoacyl-peptidase

Reaction: Cleavage of an N-acetyl or N-formyl amino acid from the N-terminus of a polypeptide

Other names: acylamino-acid-releasing enzyme; N-acylpeptide hydrolase; N-formylmethionine (fMet) aminopeptidase; α-N-acylpeptide hydrolase

Comments: Active at neutral pH. Several variants of this enzyme exist; the human erythrocyte enzyme is relatively specific for removal of N-acetylalanine from peptides. Displays dipeptidyl-peptidase activity on glycyl-peptides, perhaps as a result of mis-recognition of the glycyl residue as an uncharged N-acyl group. Inhibited by diisopropyl fluorophosphate. In peptidase family S9 (prolyl oligopeptidase family). Formerly EC

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 73562-30-8


1. Tsunazawa, S., Narita, K. and Ogata, K. Acylamino acid-releasing enzyme from rat liver. J. Biochem. (Tokyo) 77 (1975) 89-102. [PMID: 1137989]

2. Ungar, T., Nagelschmidt, M. and Struck, H. N-Acetylaminoacyl-p-nitranilidase from human placenta. Purification and some properties. Eur. J. Biochem. 97 (1979) 205-211. [PMID: 477668]

3. Kobayashi, K. and Smith, J.A. Acyl-peptide hydrolase from rat liver. Characterization of enzyme reaction. J. Biol. Chem. 262 (1987) 11435-11437 [PMID: 3305492]

[EC created 1978 as EC, transferred 1981 to EC]

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