3fao | pdb_00003fao

Crystal structure of S118A mutant 3CLSP of PRRSV

spinqualitylabelsall models 3fao, resolution 2.01Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3fao is a 1 chain structure with sequence from Porcine reproductive and respiratory syndrome virus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.01Å Ligands: PO4 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function A1E8J1_PRRSV Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Biogenesis and replication of the porcine reproductive and respiratory syndrome virus (PRRSV) include the crucial step of replicative polyprotein processing by self-encoded proteases. Whole genome bioinformatics analysis suggests that nonstructural protein 4 (nsp4) is a 3C-like serine protease (3CLSP), responsible for most of the nonstructural protein processing. The gene encoding this protease was cloned and expressed in Escherichia coli in order to confirm this prediction. The purified protein was crystallized, and the structure was solved at 1.9 A resolution. In addition, the crystal structure of the Ser118Ala mutant was determined at 2.0 A resolution. The monomeric enzyme folds into three domains, similar to that of the homologous protease of equine arteritis virus, which, like PRRSV, is a member of the family Arteriviridae in the order of Nidovirales. The active site of the PRRSV 3CLSP is located between domains I and II and harbors a canonical catalytic triad comprising Ser118, His39, and Asp64. The structure also shows an atypical oxyanion hole and a partially collapsed S1 specificity pocket. The proteolytic activity of the purified protein was assessed in vitro. Three sites joining nonstructural protein domains in the PRRSV replicative polyprotein are confirmed to be processed by the enzyme. Two of them, the nsp3/nsp4 and nsp11/nsp12 junctions, are shown to be cleaved in trans, while cis cleavage is demonstrated for the nsp4/nsp5 linker. Thus, we provide structural evidence as well as enzymatic proof of the nsp4 protein being a functional 3CLSP. We also show that the enzyme has a strong preference for glutamic acid at the P1 position of the substrate. Structure and cleavage specificity of the chymotrypsin-like serine protease (3CLSP/nsp4) of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV).,Tian X, Lu G, Gao F, Peng H, Feng Y, Ma G, Bartlam M, Tian K, Yan J, Hilgenfeld R, Gao GF J Mol Biol. 2009 Oct 2;392(4):977-93. Epub 2009 Jul 29. PMID:19646449 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

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