View source for 5etx


==Crystal structure of HCV NS3/4A protease A156T variant in complex with 5172-Linear (MK-5172 linear analogue)==
<StructureSection load='5etx' size='340' side='right'caption='[[5etx]], [[Resolution|resolution]] 2.35&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5etx]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Hepacivirus_C Hepacivirus C]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5ETX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5ETX 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]] 2.35&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=5RS:~{tert}-butyl+~{N}-[(2~{S})-1-[(2~{S},4~{R})-2-[[(1~{R},2~{R})-1-(cyclopropylsulfonylcarbamoyl)-2-ethyl-cyclopropyl]carbamoyl]-4-(3-ethyl-7-methoxy-quinoxalin-2-yl)oxy-pyrrolidin-1-yl]-3,3-dimethyl-1-oxidanylidene-butan-2-yl]carbamate'>5RS</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=5etx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5etx OCA], [https://pdbe.org/5etx PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5etx RCSB], [https://www.ebi.ac.uk/pdbsum/5etx PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5etx ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/C1KIK8_9HEPC C1KIK8_9HEPC] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Recent advances in direct-acting antivirals against Hepatitis C Virus (HCV) have led to the development of potent inhibitors, including MK-5172, that target the viral NS3/4A protease with relatively low susceptibility to resistance. MK-5172 has a P2-P4 macrocycle and a unique binding mode among current protease inhibitors where the P2 quinoxaline packs against the catalytic residues H57 and D81. However, the effect of macrocyclization on this binding mode is not clear, as is the relation between macrocyclization, thermodynamic stabilization, and susceptibility to the resistance mutation A156T. We have determined high-resolution crystal structures of linear and P1-P3 macrocyclic analogs of MK-5172 bound to WT and A156T protease and compared these structures, their molecular dynamics and experimental binding thermodynamics to the parent compound. We find that the "unique" binding mode of MK-5172 is conserved even when the P2-P4 macrocycle is removed or replaced with a P1-P3 macrocycle. While beneficial to decreasing the entropic penalty associated with binding, the constraint exerted by the P2-P4 macrocycle prevents efficient rearrangement to accommodate the A156T mutation, a deficit alleviated in the linear and P1-P3 analogs. Design of macrocyclic inhibitors against NS3/4A needs to achieve the best balance between exerting optimal conformational constraint for enhancing potency, fitting within the substrate envelope and allowing adaptability to be robust against resistance mutations.

Structural and Thermodynamic Effects of Macrocyclization in HCV NS3/4A Inhibitor MK-5172.,Soumana DI, Kurt Yilmaz N, Prachanronarong KL, Aydin C, Ali A, Schiffer CA ACS Chem Biol. 2015 Dec 18. PMID:26682473<ref>PMID:26682473</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5etx" style="background-color:#fffaf0;"></div>

==See Also==
*[[Virus protease 3D structures|Virus protease 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Hepacivirus C]]
[[Category: Large Structures]]
[[Category: Ali A]]
[[Category: Aydin C]]
[[Category: Prachanronarong KL]]
[[Category: Schiffer CA]]
[[Category: Soumana D]]
[[Category: Yilmaz NK]]