Peptidase_C30

• PFAM accession number: PF05409
• Interpro abstract (IPR008740):

  This group of cysteine peptidases correspond to MEROPS peptidase family C30 (clan PA(C)). These peptidases are related to serine endopeptidases of family S1 and are restricted to RNA viruses, where they are involved in viral polyprotein processing during replication [ (PUBMED:12093723) (PUBMED:10725411) (PUBMED:11842254) ].

  This Coronavirus (CoV) domain, peptidase C30, is also known as 3C-like proteinase (3CL-pro), or CoV main protease (M-pro) domain. CoV M-pro is a dimer where each subunit is composed of three domains I, II and III. Domains I and II consist of six-stranded antiparallel beta barrels and together resemble the architecture of chymotrypsin, and of picornaviruses 3C proteinases. The substrate-binding site is located in a cleft between these two domains. The catalytic site is situated at the centre of the cleft. A long loop connects domain II to the C-terminal domain (domain III). This latter domain, a globular cluster of five helices, has been implicated in the proteolytic activity of M-pro. In the active site of M-pro, Cys and His form a catalytic dyad. In contrast to serine proteinases and other cysteine proteinases, which have a catalytic triad, there is no third catalytic residue present [ (PUBMED:12093723) (PUBMED:12746549) (PUBMED:18094151) (PUBMED:18562531) ]. Many drugs have been developed to inhibit CoV M-pro [ (PUBMED:20021285) ].

• GO process: viral protein processing (GO:0019082)
• GO function: peptidase activity (GO:0008233)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry Peptidase_C30