View source for 4oxk


==Multiple binding modes of inhibitor PT155 to the Mycobacterium tuberculosis enoyl-ACP reductase InhA within a tetramer==
<StructureSection load='4oxk' size='340' side='right'caption='[[4oxk]], [[Resolution|resolution]] 1.84&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4oxk]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Mycobacterium_tuberculosis Mycobacterium tuberculosis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4OXK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4OXK 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]] 1.8429&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=1S5:5-(4-AMINO-2-METHYLPHENOXY)-2-HEXYL-4-HYDROXY-1-METHYLPYRIDINIUM'>1S5</scene>, <scene name='pdbligand=2NV:3,6,9,12,15-PENTAOXAOCTADECAN-17-AMINE'>2NV</scene>, <scene name='pdbligand=NAD:NICOTINAMIDE-ADENINE-DINUCLEOTIDE'>NAD</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=4oxk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4oxk OCA], [https://pdbe.org/4oxk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4oxk RCSB], [https://www.ebi.ac.uk/pdbsum/4oxk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4oxk ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/INHA_MYCTU INHA_MYCTU] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Slow-onset enzyme inhibitors are of great interest for drug discovery programs since the slow dissociation of the inhibitor from the drug-target complex results in sustained target occupancy leading to improved pharmacodynamics. However, the structural basis for slow-onset inhibition is often not fully understood, hindering the development of structure-kinetic relationships and the rational optimization of drug-target residence time. Previously we demonstrated that slow-onset inhibition of the Mycobacterium tuberculosis enoyl-ACP reductase InhA correlated with motions of a substrate-binding loop (SBL) near the active site. In the present work, X-ray crystallography and molecular dynamics simulations have been used to map the structural and energetic changes of the SBL that occur upon enzyme inhibition. Helix-6 within the SBL adopts an open conformation when the inhibitor structure or binding kinetics is substrate-like. In contrast, slow-onset inhibition results in large-scale local refolding in which helix-6 adopts a closed conformation not normally populated during substrate turnover. The open and closed conformations of helix-6 are hypothesized to represent the EI and EI* states on the two-step induced-fit reaction coordinate for enzyme inhibition. These two states were used as the end points for nudged elastic band molecular dynamics simulations resulting in two-dimensional potential energy profiles that reveal the barrier between EI and EI*, thus rationalizing the binding kinetics observed with different inhibitors. Our findings indicate that the structural basis for slow-onset kinetics can be understood once the structures of both EI and EI* have been identified, thus providing a starting point for the rational control of enzyme-inhibitor binding kinetics.

A Structural and Energetic Model for the Slow-Onset Inhibition of the Mycobacterium tuberculosis Enoyl-ACP Reductase InhA.,Li HJ, Lai CT, Pan P, Yu W, Liu N, Bommineni GR, Garcia-Diaz M, Simmerling C, Tonge PJ ACS Chem Biol. 2014 Apr 18;9(4):986-93. doi: 10.1021/cb400896g. Epub 2014 Mar 10. PMID:24527857<ref>PMID:24527857</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4oxk" style="background-color:#fffaf0;"></div>

==See Also==
*[[Enoyl-Acyl-Carrier Protein Reductase 3D structures|Enoyl-Acyl-Carrier Protein Reductase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Mycobacterium tuberculosis]]
[[Category: Garcia-Diaz M]]
[[Category: Lai CT]]
[[Category: Li HJ]]
[[Category: Liu N]]
[[Category: Pan P]]
[[Category: Simmerling C]]
[[Category: Tonge PJ]]