View source for 4krz


==Apo crystal structure of pyruvate kinase (PYK) from Trypanosoma cruzi==
<StructureSection load='4krz' size='340' side='right'caption='[[4krz]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4krz]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Trypanosoma_cruzi_strain_CL_Brener Trypanosoma cruzi strain CL Brener]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4KRZ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4KRZ 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]] 2.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</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=4krz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4krz OCA], [https://pdbe.org/4krz PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4krz RCSB], [https://www.ebi.ac.uk/pdbsum/4krz PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4krz ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q4D9Z4_TRYCC Q4D9Z4_TRYCC] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The transition between the inactive T-state (apoenzyme) and active R-state (effector bound enzyme) of Trypanosoma cruzi pyruvate kinase (PYK) is accompanied by a symmetrical 8 degrees rigid body rocking motion of the A- and C-domain cores in each of the four subunits, coupled with the formation of additional salt bridges across two of the four subunit interfaces. These salt bridges provide increased tetramer stability correlated with an enhanced specificity constant (k cat/S 0.5). A detailed kinetic and structural comparison between the potential drug target PYKs from the pathogenic protists T. cruzi, T. brucei and Leishmania mexicana shows that their allosteric mechanism is conserved. By contrast, a structural comparison of trypanosomatid PYKs with the evolutionarily divergent PYKs of humans and of bacteria shows that they have adopted different allosteric strategies. The underlying principle in each case is to maximize (k cat/S 0.5) by stabilizing and rigidifying the tetramer in an active R-state conformation. However, bacterial and mammalian PYKs have evolved alternative ways of locking the tetramers together. In contrast to the divergent allosteric mechanisms, the PYK active sites are highly conserved across species. Selective disruption of the varied allosteric mechanisms may therefore provide a useful approach for the design of species-specific inhibitors.

Structures of pyruvate kinases display evolutionarily divergent allosteric strategies.,Morgan HP, Zhong W, McNae IW, Michels PA, Fothergill-Gilmore LA, Walkinshaw MD R Soc Open Sci. 2014 Sep 24;1(1):140120. doi: 10.1098/rsos.140120. eCollection, 2014 Sep. PMID:26064527<ref>PMID:26064527</ref>

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

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