4oyr: Difference between revisions
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''' | ==Competition of the small inhibitor PT91 with large fatty acyl substrate of the Mycobacterium tuberculosis enoyl-ACP reductase InhA by induced substrate-binding loop refolding== | ||
<StructureSection load='4oyr' size='340' side='right' caption='[[4oyr]], [[Resolution|resolution]] 2.30Å' scene=''> | |||
== Structural highlights == | |||
[[4oyr]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4OYR OCA]. <br> | |||
<b>Activity:</b> <span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span><br> | |||
== 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®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Garcia-Diaz, M.]] | |||
[[Category: Lai, C T.]] | |||
[[Category: Li, H J.]] | |||
[[Category: Liu, N.]] | |||
[[Category: Pan, P.]] | |||
[[Category: Simmerling, C.]] | |||
[[Category: Tonge, P J.]] | |||
[[Category: Bacterial fatty acid biosynthesis]] | |||
[[Category: Enzyme-inhibitor complex]] | |||
[[Category: Induced-fit]] | |||
[[Category: Substrate-binding loop refolding]] | |||