View source for 2op9


==Substrate Specificity Profiling and Identification of a New Class of Inhibitor for the Major Protease of the SARS Coronavirus==
<StructureSection load='2op9' size='340' side='right'caption='[[2op9]], [[Resolution|resolution]] 1.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2op9]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Severe_acute_respiratory_syndrome-related_coronavirus Severe acute respiratory syndrome-related coronavirus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2OP9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2OP9 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.8&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=WR1:NALPHA-[(BENZYLOXY)CARBONYL]-N-[(1R)-4-HYDROXY-1-METHYL-2-OXOBUTYL]-L-PHENYLALANINAMIDE'>WR1</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2op9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2op9 OCA], [https://pdbe.org/2op9 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2op9 RCSB], [https://www.ebi.ac.uk/pdbsum/2op9 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2op9 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/R1AB_SARS R1AB_SARS] Multifunctional protein involved in the transcription and replication of viral RNAs. Contains the proteinases responsible for the cleavages of the polyprotein.  Inhibits host translation by interacting with the 40S ribosomal subunit. The nsp1-40S ribosome complex further induces an endonucleolytic cleavage near the 5'UTR of host mRNAs, targeting them for degradation. Viral mRNAs are not susceptible to nsp1-mediated endonucleolytic RNA cleavage thanks to the presence of a 5'-end leader sequence and are therefore protected from degradation. By suppressing host gene expression, nsp1 facilitates efficient viral gene expression in infected cells and evasion from host immune response (PubMed:23035226). May disrupt nuclear pore function by binding and displacing host NUP93 (PubMed:30943371).<ref>PMID:23035226</ref> <ref>PMID:30943371</ref>   May play a role in the modulation of host cell survival signaling pathway by interacting with host PHB and PHB2. Indeed, these two proteins play a role in maintaining the functional integrity of the mitochondria and protecting cells from various stresses.<ref>PMID:19640993</ref>   Responsible for the cleavages located at the N-terminus of the replicase polyprotein. In addition, PL-PRO possesses a deubiquitinating/deISGylating activity and processes both 'Lys-48'- and 'Lys-63'-linked polyubiquitin chains from cellular substrates (PubMed:17692280). Plays a role in host membrane rearrangement that leads to creation of cytoplasmic double-membrane vesicles (DMV) necessary for viral replication. Nsp3, nsp4 and nsp6 together are sufficient to form DMV (PubMed:24410069). Antagonizes innate immune induction of type I interferon by blocking the phosphorylation, dimerization and subsequent nuclear translocation of host IRF3 (PubMed:19369340, PubMed:24622840). Prevents also host NF-kappa-B signaling.<ref>PMID:16271890</ref> <ref>PMID:17692280</ref> <ref>PMID:19369340</ref> <ref>PMID:24622840</ref> <ref>PMID:24410069</ref>   Plays a role in host membrane rearrangement that leads to creation of cytoplasmic double-membrane vesicles (DMV) necessary for viral replication. Alone appears incapable to induce membrane curvature, but together with nsp3 is able to induce paired membranes. Nsp3, nsp4 and nsp6 together are sufficient to form DMV.<ref>PMID:23943763</ref> <ref>PMID:24410069</ref>   Cleaves the C-terminus of replicase polyprotein at 11 sites. Recognizes substrates containing the core sequence [ILMVF]-Q-|-[SGACN]. Also able to bind an ADP-ribose-1''-phosphate (ADRP). May cleave host ATP6V1G1 thereby modifying host vacuoles intracellular pH.[PROSITE-ProRule:PRU00772]<ref>PMID:16226257</ref>   Plays a role in host membrane rearrangement that leads to creation of cytoplasmic double-membrane vesicles (DMV) necessary for viral replication. Nsp3, nsp4 and nsp6 together are sufficient to form DMV (PubMed:24410069). Plays a role in the initial induction of autophagosomes from host reticulum endoplasmic. Later, limits the expansion of these phagosomes that are no longer able to deliver viral components to lysosomes (PubMed:24991833).<ref>PMID:24991833</ref> <ref>PMID:24410069</ref>   Forms a hexadecamer with nsp8 (8 subunits of each) that may participate in viral replication by acting as a primase. Alternatively, may synthesize substantially longer products than oligonucleotide primers.<ref>PMID:22039154</ref>   Forms a hexadecamer with nsp7 (8 subunits of each) that may participate in viral replication by acting as a primase. Alternatively, may synthesize substantially longer products than oligonucleotide primers.<ref>PMID:22039154</ref>   May participate in viral replication by acting as a ssRNA-binding protein.<ref>PMID:19153232</ref>   Plays a pivotal role in viral transcription by stimulating both nsp14 3'-5' exoribonuclease and nsp16 2'-O-methyltransferase activities. Therefore plays an essential role in viral mRNAs cap methylation.<ref>PMID:22635272</ref>   Responsible for replication and transcription of the viral RNA genome.<ref>PMID:22791111</ref>   Multi-functional protein with a zinc-binding domain in N-terminus displaying RNA and DNA duplex-unwinding activities with 5' to 3' polarity. Activity of helicase is dependent on magnesium.<ref>PMID:12917423</ref> <ref>PMID:22615777</ref>   Enzyme possessing two different activities: an exoribonuclease activity acting on both ssRNA and dsRNA in a 3' to 5' direction and a N7-guanine methyltransferase activity (PubMed:16549795, PubMed:20421945, PubMed:22635272). Acts as a proofreading exoribonuclease for RNA replication, thereby lowering The sensitivity of the virus to RNA mutagens (PubMed:23966862, PubMed:29511076, PubMed:21593585).<ref>PMID:16549795</ref> <ref>PMID:20421945</ref> <ref>PMID:21593585</ref> <ref>PMID:22635272</ref> <ref>PMID:23966862</ref> <ref>PMID:29511076</ref>   Mn(2+)-dependent, uridylate-specific enzyme, which leaves 2'-3'-cyclic phosphates 5' to the cleaved bond.  Methyltransferase that mediates mRNA cap 2'-O-ribose methylation to the 5'-cap structure of viral mRNAs. N7-methyl guanosine cap is a prerequisite for binding of nsp16. Therefore plays an essential role in viral mRNAs cap methylation which is essential to evade immune system.<ref>PMID:18417574</ref> <ref>PMID:20421945</ref> 
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/op/2op9_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2op9 ConSurf].
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== Publication Abstract from PubMed ==
Severe acute respiratory syndrome (SARS) is an emerging infectious disease associated with a high rate of mortality. The SARS-associated coronavirus (SARS-CoV) has been identified as the etiological agent of the disease. Although public health procedures have been effective in combating the spread of SARS, concern remains about the possibility of a recurrence. Various approaches are being pursued for the development of efficacious therapeutics. One promising approach is to develop small molecule inhibitors of the essential major polyprotein processing protease 3Clpro. Here we report a complete description of the tetrapeptide substrate specificity of 3Clpro using fully degenerate peptide libraries consisting of all 160,000 possible naturally occurring tetrapeptides. The substrate specificity data show the expected P1-Gln P2-Leu specificity and elucidate a novel preference for P1-His containing substrates equal to the expected preference for P1-Gln. These data were then used to develop optimal substrates for a high-throughput screen of a 2000 compound small-molecule inhibitor library consisting of known cysteine protease inhibitor scaffolds. We also report the 1.8 A X-ray crystal structure of 3Clpro bound to an irreversible inhibitor. This inhibitor, an alpha,beta-epoxyketone, inhibits 3Clpro with a k3/Ki of 0.002 microM(-1) s(-1) in a mode consistent with the substrate specificity data. Finally, we report the successful rational improvement of this scaffold with second generation inhibitors. These data provide the foundation for a rational small-molecule inhibitor design effort based upon the inhibitor scaffold identified, the crystal structure of the complex, and a more complete understanding of P1-P4 substrate specificity.

Substrate specificity profiling and identification of a new class of inhibitor for the major protease of the SARS coronavirus.,Goetz DH, Choe Y, Hansell E, Chen YT, McDowell M, Jonsson CB, Roush WR, McKerrow J, Craik CS Biochemistry. 2007 Jul 31;46(30):8744-52. Epub 2007 Jul 3. PMID:17605471<ref>PMID:17605471</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Virus protease 3D structures|Virus protease 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Severe acute respiratory syndrome-related coronavirus]]
[[Category: Craik CS]]
[[Category: Goetz DH]]