View source for 4kct


==Pyruvate kinase (PYK) from Trypanosoma brucei soaked with Oxaloacetate==
<StructureSection load='4kct' size='340' side='right'caption='[[4kct]], [[Resolution|resolution]] 1.95&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4kct]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Trypanosoma_brucei_brucei Trypanosoma brucei brucei]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4KCT OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4KCT 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]] 1.95&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FDP:FRUCTOSE-2,6-DIPHOSPHATE'>FDP</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=PYR:PYRUVIC+ACID'>PYR</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=4kct FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4kct OCA], [https://pdbe.org/4kct PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4kct RCSB], [https://www.ebi.ac.uk/pdbsum/4kct PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4kct ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/KPYK1_TRYBB KPYK1_TRYBB] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The phosphotransfer mechanism of pyruvate kinases (PYKs) has been studied in detail, but the mechanism of the intrinsic decarboxylase reaction catalysed by PYKs is still unknown. 1H NMR was used in this work to follow oxaloacetate (OAA) decarboxylation by trypanosomatid and human PYKs confirming that the decarboxylase activity is conserved across distantly related species. Crystal structures of Trypanosoma brucei PYK (TbPYK) complexed with the product of the decarboxylase reaction (pyruvate), and a series of substrate analogues (D-malate, alpha-ketoglutarate and oxalate) show that the OAA analogues bind to the kinase active site with similar binding modes, confirming that both decarboxylase and kinase activities share a common site for substrate binding and catalysis. Decarboxylation of OAA as monitored by NMR for TbPYK is relatively slow with turn-over values of 0.86 s-1 and 1.47 s-1 in the absence and presence of fructose 2,6-bisphosphate (F26BP), respectively. Human M1PYK has a measured turn-over value of 0.50 s-1. The X-ray structures explain why the decarboxylation activity is specific for OAA and is not general for alpha-keto acid analogues. Conservation of the decarboxylase reaction across divergent species is a consequence of piggybacking on the conserved kinase mechanism which requires a stabilised enol intermediate.

Pyruvate kinases have an intrinsic and conserved decarboxylase activity.,Zhong W, Morgan HP, Nowicki MW, McNae IW, Yuan M, Bella J, Michels PA, Fothergill-Gilmore LA, Walkinshaw MD Biochem J. 2013 Dec 13. PMID:24328825<ref>PMID:24328825</ref>

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

==See Also==
*[[Pyruvate kinase 3D structures|Pyruvate kinase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Trypanosoma brucei brucei]]
[[Category: Fothergill-Gilmore LA]]
[[Category: McNae IW]]
[[Category: Michels PAM]]
[[Category: Morgan HP]]
[[Category: Walkinshaw MD]]
[[Category: Zhong W]]