5cyv

<StructureSection load='5cyv' size='340' side='right' caption='[[5cyv]], [[Resolution|resolution]] 1.52&Aring;' scene=''>

<table><tr><td colspan='2'>[[5cyv]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5CYV OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5CYV FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=WCA:P-COUMAROYL-COA'>WCA</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3fm5|3fm5]]</td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5cyv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5cyv OCA], [http://pdbe.org/5cyv PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5cyv RCSB], [http://www.ebi.ac.uk/pdbsum/5cyv PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5cyv ProSAT]</span></td></tr>

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

CouR, a MarR-type transcriptional repressor, regulates the cou genes, encoding p-hydroxycinnamate catabolism in the soil bacterium Rhodococcus jostii RHA1. The CouR dimer bound two molecules of the catabolite p-coumaroyl-CoA (Kd = 11 +/- 1 muM). The presence of p-coumaroyl-CoA, but neither p-coumarate nor CoASH, abrogated CouR's binding to its operator DNA in vitro. The crystal structures of ligand-free CouR and its p-coumaroyl-CoA-bound form showed no significant conformational differences, in contrast to other MarR regulators. The CouR-p-coumaroyl-CoA structure revealed two ligand molecules bound to the CouR dimer with their phenolic moieties occupying equivalent hydrophobic pockets in each protomer and their CoA moieties adopting non-equivalent positions to mask the regulator's predicted DNA-binding surface. More specifically, the CoA phosphates formed salt bridges with predicted DNA-binding residues Arg36 and Arg38, changing the overall charge of the DNA-binding surface. The substitution of either arginine with alanine completely abrogated the ability of CouR to bind DNA. By contrast, the R36A/R38A double variant retained a relatively high affinity for p-coumaroyl-CoA (Kd = 89 +/- 6 muM). Together, our data point to a novel mechanism of action in which the ligand abrogates the repressor's ability to bind DNA by steric occlusion of key DNA-binding residues and charge repulsion of the DNA backbone.

 

== References ==

[[Category: Dong, A]]

[[Category: Joachimiak, A]]

[[Category: Structural genomic]]

[[Category: Savchenko, A]]

[[Category: Stogios, P J]]

[[Category: Xu, X]]

[[Category: Marr]]

[[Category: Transcriptional regulator]]