The domain within your query sequence starts at position 491 and ends at position 574; the E-value for the Peptidase_S7 domain shown below is 6.9e-9.



PFAM accession number:PF00949
Interpro abstract (IPR001850):

The viral genome of Flavivirus is a positive strand RNA that encodes a single polyprotein precursor. Processing of the polyprotein precursor into mature proteins is carried out by the host signal peptidase and by NS3 serine protease, which requires NS2B ( IPR000487 ) as a cofactor [ (PUBMED:10026173) ].

Pathogenic members of the flavivirus family, including West Nile Virus (WNV) and Dengue Virus (DV), are growing global threats for which there are no specific treatments. The genome encodes three structural proteins found in the mature virion (C, prM, and E) and seven "nonstructural" (i.e., not part of the virion architecture) proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5). Full-length NS3 is a bifunctional protein. The N-terminal 175 residues comprise a chymotrypsin-like protease, while the C-terminal portion is a helicase. The NS2B protein, which is located in the polypeptide precursor immediately upstream of the NS3 protease domain, functions as the cofactor for NS3 protease. A 35-48 residue central portion is required for protease activity in vitro, while N- and C-terminal flanking hydrophobic regions are predicted to anchor the NS2B-NS3 complex into the host endoplasmic reticulum membrane. The two component flaviviral enzyme NS2B-NS3 cleaves the viral polyprotein precursor within the host cell, a process that is required for viral replication [ (PUBMED:17400917) (PUBMED:19693793) (PUBMED:20042502) ]. The NS3 protease forms the MEROPS peptidase family S7 (flavivirin family), clan PA.

The NS3 protease has a classical serine protease catalytic triad (His, Asp, and Ser). The enzymatic activity is enhanced by interacting with the central 40 amino acid of NS2B which acts as an essential cofactor. The NS3 protease domain has an overall structure of two barrels made of six beta sheets each, with the active site located in the cleft between the barrels. The NS2B hydrophilic core cofactor contributes one of the N-terminal beta sheets [ (PUBMED:17400917) (PUBMED:19693793) (PUBMED:20042502) ].

GO function:RNA helicase activity (GO:0003724), ATP binding (GO:0005524), RNA binding (GO:0003723)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry Peptidase_S7