View source for 5ktn


==Crystal structure of Pyrococcus horikoshii quinolinate synthase (NadA) with bound dihydroxyacetone phosphate (DHAP) and Fe4S4 cluster==
<StructureSection load='5ktn' size='340' side='right'caption='[[5ktn]], [[Resolution|resolution]] 1.34&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5ktn]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Pyrococcus_horikoshii_OT3 Pyrococcus horikoshii OT3]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5KTN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5KTN 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]] 1.34&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=13P:1,3-DIHYDROXYACETONEPHOSPHATE'>13P</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=NH4:AMMONIUM+ION'>NH4</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=5ktn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5ktn OCA], [https://pdbe.org/5ktn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5ktn RCSB], [https://www.ebi.ac.uk/pdbsum/5ktn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5ktn ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/NADA_PYRHO NADA_PYRHO] Catalyzes the condensation of iminoaspartate with dihydroxyacetone phosphate to form quinolinate (By similarity).
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The quinolinate synthase of prokaryotes and photosynthetic eukaryotes, NadA, contains a [4Fe-4S] cluster with unknown function. We report crystal structures of Pyrococcus horikoshii NadA in complex with dihydroxyacetone phosphate (DHAP), iminoaspartate analogues, and quinolinate. DHAP adopts a nearly planar conformation and chelates the [4Fe-4S] cluster via its keto and hydroxyl groups. The active site architecture suggests that the cluster acts as a Lewis acid in enediolate formation, like zinc in class II aldolases. The DHAP and putative iminoaspartate structures suggest a model for a condensed intermediate. The ensemble of structures suggests a two-state system, which may be exploited in early steps.

Crystal Structures of the Iron-Sulfur Cluster-Dependent Quinolinate Synthase in Complex with Dihydroxyacetone Phosphate, Iminoaspartate Analogues, and Quinolinate.,Fenwick MK, Ealick SE Biochemistry. 2016 Jul 22. PMID:27404889<ref>PMID:27404889</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5ktn" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Pyrococcus horikoshii OT3]]
[[Category: Ealick SE]]
[[Category: Fenwick MK]]