IUBMB Enzyme Nomenclature


Accepted name: tripeptidyl-peptidase I

Reaction: Release of an N-terminal tripeptide from a polypeptide, but also has endopeptidase activity.

Other name(s): tripeptidyl aminopeptidase; tripeptidyl peptidase

Comments: A lysosomal enzyme that is active at acidic pH. Deficient in classical late-infantile neuronal ceroid lipofuscinosis brain tissue. Belongs In peptidase family S53. Formerly included in EC

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 151662-36-1


1. Ezaki, J., Tanida, I., Kanehagi, N. and Kominami, E. A lysosomal proteinase, the late infantile neuronal ceroid lipofuscinosis gene (CLN2) product, is essential for degradation of a hydrophobic protein, the subunit c of ATP synthase. J. Neurochem. 72 (1999) 2573-2582. [PMID: 10349869]

2. Rawlings, N.D. and Barrett, A.J. Tripeptidyl-peptidase I is apparently the CLN2 protein absent in classical late-infantile neuronal ceroid lipofuscinosis. Biochim. Biophys. Acta 1429 (1999) 496-500. [PMID: 9989235]

3. Ezaki, J., Takeda-Ezaki, M., Oda, K. and Kominami, E. Characterization of endopeptidase activity of tripeptidyl peptidase-I/CLN2 protein which is deficient in classical late infantile neuronal ceroid lipofuscinosis. Biochem. Biophys. Res. Commun. 268 (2000) 904-908. [PMID: 10679303]

4. Junaid, M.A., Wu, G.X. and Pullarkat, R.K. Purification and characterization of bovine brain lysosomal pepstatin-insensitive proteinase, the gene product deficient in the human late-infantile neuronal ceroid lipofuscinosis. J. Neurochem. 74 (2000) 287-294. [PMID: 10617131]

5. Lin, L., Sohar, I., Lackland, H. and Lobel, P. The human CLN2 protein/tripeptidyl-peptidase I is a serine protease that autoactivates at acidic pH. J. Biol. Chem. 276 (2001) 2249-2255. [PMID: 11054422]

[EC created 1992 (part of EC created 1989, incorporated 1992), modified 2000, modified 2001, modified 2003]

Return to EC 3.4.14 home page
Return to EC 3.4 home page
Return to EC 3 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page