IUBMB Enzyme Nomenclature


Accepted name: papain

Reaction: Hydrolysis of proteins with broad specificity for peptide bonds, but preference for an amino acid bearing a large hydrophobic side chain at the P2 position. Does not accept Val in P1'

Other name(s): papayotin; summetrin; velardon; papaine; Papaya peptidase I

Comments: Type example of peptidase family C1 from latex of the papaya (Carica papaya) fruit. Inhibited by compound E-64 and proteins of the cystatin family. Formerly EC

Links to other databases: BRENDA, EXPASY, GTD, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 9001-73-4


1. Kamphuis, I.G., Drenth, J. and Baker, E.N. Thiol proteases. Comparative studies based on the high-resolution structures of papain and actinidin, and on amino acid sequence information for cathepsins B and H, and stem bromelain. J. Mol. Biol. 182 (1985) 317-329. [PMID: 3889350]

2. Ménard, R. and Storer, A.C. Papain. In: Handbook of Proteolytic Enzymes, Barrett, A.J., Rawlings, N.D. and Woessner, J.F. eds), p.555-557 (1998) Academic Press, London.

[EC created 1961 as EC, transferred 1972 to EC, modified 1976, modified 2000]

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