IUBMB Enzyme Nomenclature


Accepted name: pestivirus NS3 polyprotein peptidase

Reaction: Leu is conserved at position P1 for all four cleavage sites. Alanine is found at position P1' of the NS4A-NS4B cleavage site, whereas serine is found at position P1' of the NS3-NS4A, NS4B-NS5A and NS5A-NS5B cleavage sites

Other name(s): border disease virus NS3 endopeptidase; BDV NS3 endopeptidase; bovine viral diarrhea virus NS3 endopeptidase; BVDV NS3 endopeptidase; classical swine fever virus NS3 endopeptidase; CSFV NS3 endopeptidase; p80

Comments: The polyprotein of noncytopathogenic pestiviruses is cleaved co- and post-translationally into at least 11 proteins (Npro, C, Erns, E1, E2, p7, NS2-3, NS4A, NS4B, NS5A, and NS5B) [2]. The genomes of cytopathogenic pestivirus strains express at least one additional protein, called NS3 (p80) [2]. This enzyme, which resides in the N-terminal region of NS3 (nonstructural protein 3), is essential for generation of its own C-terminus and for processing of the downstream cleavage sites, leading to the release of the pestivirus nonstructural proteins NS4A, NS4B, NS5A and NS5B [1,2]. Belongs in peptidase family S31.

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number:


1. Wiskerchen, M. and Collett, M.S. Pestivirus gene expression: protein p80 of bovine viral diarrhea virus is a proteinase involved in polyprotein processing. Virology 184 (1991) 341-350. [PMID: 1651596]

2. Tautz, N., Elbers, K., Stoll, D., Meyers, G. and Thiel, H.J. Serine protease of pestiviruses: determination of cleavage sites. J. Virol. 71 (1997) 5415-5422. [PMID: 9188613]

3. Xu, J., Mendez, E., Caron, P.R., Lin, C., Murcko, M.A., Collett, M.S. and Rice, C.M. Bovine viral diarrhea virus NS3 serine proteinase: polyprotein cleavage sites, cofactor requirements, and molecular model of an enzyme essential for pestivirus replication. J. Virol. 71 (1997) 5312-5322. [PMID: 9188600]

4. Tautz, N., Kaiser, A. and Thiel, H.J. NS3 serine protease of bovine viral diarrhea virus: characterization of active site residues, NS4A cofactor domain, and protease-cofactor interactions. Virology 273 (2000) 351-363. [PMID: 10915606]

[EC created 2006]

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