View source for 4uxi


==Leishmania major Thymidine Kinase in complex with thymidine==
<StructureSection load='4uxi' size='340' side='right'caption='[[4uxi]], [[Resolution|resolution]] 2.74&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4uxi]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Leishmania_major Leishmania major]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4UXI OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4UXI 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]] 2.74&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene>, <scene name='pdbligand=THM:THYMIDINE'>THM</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=4uxi FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4uxi OCA], [https://pdbe.org/4uxi PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4uxi RCSB], [https://www.ebi.ac.uk/pdbsum/4uxi PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4uxi ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q4QC75_LEIMA Q4QC75_LEIMA] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Leishmania spp. is a protozoan parasite and the causative agent of leishmaniasis. Thymidine kinase (TK) catalyses the transfer of the gamma-phosphate of ATP to 2'-deoxythymidine (dThd) forming thymidine monophosphate (dTMP). L. major Type II TK (LmTK) has been previously shown to be important for infectivity of the parasite and therefore has potential as a drug target for anti-leishmanial therapy. In this study, we determined the enzymatic properties and the 3D structures of holo forms of the enzyme. LmTK efficiently phosphorylates dThd and dUrd and has high structural homology to TKs from other species. However, it significantly differs in its kinetic properties from Trypanosoma brucei TK since purines are not substrates of the enzyme and dNTPs such as dUTP inhibit LmTK. The enzyme had Km and kcat values for dThd of 1.1 muM and 2.62 s-1 and exhibits cooperative binding for ATP. Additionally, we show that the anti-retroviral prodrug zidovudine (3-azido-3-deoxythymidine, AZT) and 5'-modified dUrd can be readily phosphorylated by LmTK. The production of recombinant enzyme at a level suitable for structural studies was achieved by the construction of C-terminal truncated versions of the enzyme and the use of a baculoviral expression system. The structures of the catalytic core of LmTK in complex with dThd, the negative feedback regulator dTTP and the bi-substrate analogue AP5dT, were determined to 2.74, 3.00 and 2.40 A, respectively, and provide the structural basis for exclusion of purines and dNTP inhibition. The results will aid the process of rational drug design with LmTK as a potential target for anti-leishmanial drugs.

Structural and Kinetic Characterization of Thymidine Kinase from Leishmania major.,Timm J, Bosch-Navarrete C, Recio E, Nettleship JE, Rada H, Gonzalez-Pacanowska D, Wilson KS PLoS Negl Trop Dis. 2015 May 15;9(5):e0003781. doi: 10.1371/journal.pntd.0003781., eCollection 2015 May. PMID:25978379<ref>PMID:25978379</ref>

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

==See Also==
*[[Thymidine kinase 3D structures|Thymidine kinase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Leishmania major]]
[[Category: Bosch-Navarrete C]]
[[Category: Gonzalez-Pacanowska D]]
[[Category: Nettleship JE]]
[[Category: Rada H]]
[[Category: Recio E]]
[[Category: Timm J]]
[[Category: Wilson KS]]