View source for 1lik


==STRUCTURE OF T. GONDII ADENOSINE KINASE BOUND TO ADENOSINE==
<StructureSection load='1lik' size='340' side='right'caption='[[1lik]], [[Resolution|resolution]] 2.55&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1lik]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Toxoplasma_gondii Toxoplasma gondii]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1dh0 1dh0]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LIK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1LIK 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]] 2.55&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADN:ADENOSINE'>ADN</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=1lik FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1lik OCA], [https://pdbe.org/1lik PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1lik RCSB], [https://www.ebi.ac.uk/pdbsum/1lik PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1lik ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ADK_TOXGO ADK_TOXGO] ATP-dependent phosphorylation of adenosine and other related nucleoside analogs to monophosphate derivatives. It is a key purine metabolic enzyme in the opportunistic parasitic protozoan toxoplasma gondii as it cannot synthesize purines de novo.
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/li/1lik_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1lik ConSurf].
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== Publication Abstract from PubMed ==
Adenosine kinase (AK) is a key purine metabolic enzyme from the opportunistic parasitic protozoan Toxoplasma gondii and belongs to the family of carbohydrate kinases that includes ribokinase. To understand the catalytic mechanism of AK, we determined the structures of the T. gondii apo AK, AK:adenosine complex and the AK:adenosine:AMP-PCP complex to 2.55 A, 2.50 A and 1.71 A resolution, respectively. These structures reveal a novel catalytic mechanism that involves an adenosine-induced domain rotation of 30 degrees and a newly described anion hole (DTXGAGD), requiring a helix-to-coil conformational change that is induced by ATP binding. Nucleotide binding also evokes a coil-to-helix transition that completes the formation of the ATP binding pocket. A conserved dipeptide, Gly68-Gly69, which is located at the bottom of the adenosine-binding site, functions as the switch for domain rotation. The synergistic structural changes that occur upon substrate binding sequester the adenosine and the ATP gamma phosphate from solvent and optimally position the substrates for catalysis. Finally, the 1.84 A resolution structure of an AK:7-iodotubercidin:AMP-PCP complex reveals the basis for the higher affinity binding of this prodrug over adenosine and thus provides a scaffold for the design of new inhibitors and subversive substrates that target the T. gondii AK.

Crystal structures of Toxoplasma gondii adenosine kinase reveal a novel catalytic mechanism and prodrug binding.,Schumacher MA, Scott DM, Mathews II, Ealick SE, Roos DS, Ullman B, Brennan RG J Mol Biol. 2000 May 19;298(5):875-93. PMID:10801355<ref>PMID:10801355</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1lik" style="background-color:#fffaf0;"></div>

==See Also==
*[[Adenosine kinase 3D structures|Adenosine kinase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Toxoplasma gondii]]
[[Category: Brennan RG]]
[[Category: Ealick SE]]
[[Category: Mathews II]]
[[Category: Roos DS]]
[[Category: Schumacher MA]]
[[Category: Scott DM]]
[[Category: Ullman B]]