View source for 1cza


==MUTANT MONOMER OF RECOMBINANT HUMAN HEXOKINASE TYPE I COMPLEXED WITH GLUCOSE, GLUCOSE-6-PHOSPHATE, AND ADP==
<StructureSection load='1cza' size='340' side='right'caption='[[1cza]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1cza]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1CZA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1CZA FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=G6P:ALPHA-D-GLUCOSE-6-PHOSPHATE'>G6P</scene>, <scene name='pdbligand=GLC:ALPHA-D-GLUCOSE'>GLC</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1hkb|1hkb]], [[1hkc|1hkc]]</div></td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Hexokinase Hexokinase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.1 2.7.1.1] </span></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=1cza FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1cza OCA], [https://pdbe.org/1cza PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1cza RCSB], [https://www.ebi.ac.uk/pdbsum/1cza PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1cza ProSAT]</span></td></tr>
</table>
== Disease ==
[[https://www.uniprot.org/uniprot/HXK1_HUMAN HXK1_HUMAN]] Defects in HK1 are the cause of hexokinase deficiency (HK deficiency) [MIM:[https://omim.org/entry/235700 235700]]. HK deficiency is a rare autosomal recessive disease with nonspherocytic hemolytic anemia as the predominant clinical feature. 
== 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/cz/1cza_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=1cza ConSurf].
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== Publication Abstract from PubMed ==
Hexokinase I, the pacemaker of glycolysis in brain tissue, is composed of two structurally similar halves connected by an alpha-helix. The enzyme dimerizes at elevated protein concentrations in solution and in crystal structures; however, almost all published data reflect the properties of a hexokinase I monomer in solution. Crystal structures of mutant forms of recombinant human hexokinase I, presented here, reveal the enzyme monomer for the first time. The mutant hexokinases bind both glucose 6-phosphate and glucose with high affinity to their N and C-terminal halves, and ADP, also with high affinity, to a site near the N terminus of the polypeptide chain. Exposure of the monomer crystals to ADP in the complete absence of glucose 6-phosphate reveals a second binding site for adenine nucleotides at the putative active site (C-half), with conformational changes extending 15 A to the contact interface between the N and C-halves. The structures reveal distinct conformational states for the C-half and a rigid-body rotation of the N-half, as possible elements of a structure-based mechanism for allosteric regulation of catalysis.

Crystal structures of mutant monomeric hexokinase I reveal multiple ADP binding sites and conformational changes relevant to allosteric regulation.,Aleshin AE, Kirby C, Liu X, Bourenkov GP, Bartunik HD, Fromm HJ, Honzatko RB J Mol Biol. 2000 Mar 3;296(4):1001-15. PMID:10686099<ref>PMID:10686099</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 1cza" style="background-color:#fffaf0;"></div>

==See Also==
*[[Hexokinase 3D structures|Hexokinase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Hexokinase]]
[[Category: Human]]
[[Category: Large Structures]]
[[Category: Aleshin, A E]]
[[Category: Bartunik, H D]]
[[Category: Bourenkov, G P]]
[[Category: Fromm, H J]]
[[Category: Honzatko, R B]]
[[Category: Kirby, C]]
[[Category: Liu, X]]
[[Category: Structurally homologous domain]]
[[Category: Transferase]]