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1hkb
From Proteopedia
(Difference between revisions)
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| - | + | ==CRYSTAL STRUCTURE OF RECOMBINANT HUMAN BRAIN HEXOKINASE TYPE I COMPLEXED WITH GLUCOSE AND GLUCOSE-6-PHOSPHATE== | |
| - | + | <StructureSection load='1hkb' size='340' side='right' caption='[[1hkb]], [[Resolution|resolution]] 2.80Å' scene=''> | |
| - | + | == Structural highlights == | |
| - | + | <table><tr><td colspan='2'>[[1hkb]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1HKB OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1HKB FirstGlance]. <br> | |
| - | ==Disease== | + | </td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=BGC:BETA-D-GLUCOSE'>BGC</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=G6P:ALPHA-D-GLUCOSE-6-PHOSPHATE'>G6P</scene><br> |
| + | <tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Hexokinase Hexokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.1 2.7.1.1] </span></td></tr> | ||
| + | <tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1hkb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1hkb OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1hkb RCSB], [http://www.ebi.ac.uk/pdbsum/1hkb PDBsum]</span></td></tr> | ||
| + | <table> | ||
| + | == Disease == | ||
[[http://www.uniprot.org/uniprot/HXK1_HUMAN HXK1_HUMAN]] Defects in HK1 are the cause of hexokinase deficiency (HK deficiency) [MIM:[http://omim.org/entry/235700 235700]]. HK deficiency is a rare autosomal recessive disease with nonspherocytic hemolytic anemia as the predominant clinical feature. | [[http://www.uniprot.org/uniprot/HXK1_HUMAN HXK1_HUMAN]] Defects in HK1 are the cause of hexokinase deficiency (HK deficiency) [MIM:[http://omim.org/entry/235700 235700]]. HK deficiency is a rare autosomal recessive disease with nonspherocytic hemolytic anemia as the predominant clinical feature. | ||
| + | == Function == | ||
| - | == | + | == 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/hk/1hkb_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/chain_selection.php?pdb_ID=2ata ConSurf]. | ||
| + | <div style="clear:both"></div> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | BACKGROUND: Hexokinase I is the pacemaker of glycolysis in brain tissue. The type I isozyme exhibits unique regulatory properties in that physiological levels of phosphate relieve potent inhibition by the product, glucose-6-phosphate (Gluc-6-P). The 100 kDa polypeptide chain of hexokinase I consists of a C-terminal (catalytic) domain and an N-terminal (regulatory) domain. Structures of ligated hexokinase I should provide a basis for understanding mechanisms of catalysis and regulation at an atomic level. RESULTS: The complex of human hexokinase I with glucose and Gluc-6-P (determined to 2.8 A resolution) is a dimer with twofold molecular symmetry. The N- and C-terminal domains of one monomer interact with the C- and N-terminal domains, respectively, of the symmetry-related monomer. The two domains of a monomer are connected by a single alpha helix and each have the fold of yeast hexokinase. Salt links between a possible cation-binding loop of the N-terminal domain and a loop of the C-terminal domain may be important to regulation. Each domain binds single glucose and Gluc-6-P molecules in proximity to each other. The 6-phosphoryl group of bound Gluc-6-P at the C-terminal domain occupies the putative binding site for ATP, whereas the 6-phosphoryl group at the N-terminal domain may overlap the binding site for phosphate. CONCLUSIONS: The binding synergism of glucose and Gluc-6-P probably arises out of the mutual stabilization of a common (glucose-bound) conformation of hexokinase I. Conformational changes in the N-terminal domain in response to glucose, phosphate, and/or Gluc-6-P may influence the binding of ATP to the C-terminal domain. | ||
| + | |||
| + | The mechanism of regulation of hexokinase: new insights from the crystal structure of recombinant human brain hexokinase complexed with glucose and glucose-6-phosphate.,Aleshin AE, Zeng C, Bourenkov GP, Bartunik HD, Fromm HJ, Honzatko RB Structure. 1998 Jan 15;6(1):39-50. PMID:9493266<ref>PMID:9493266</ref> | ||
| + | |||
| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| + | </div> | ||
==See Also== | ==See Also== | ||
*[[Hexokinase|Hexokinase]] | *[[Hexokinase|Hexokinase]] | ||
| - | + | == References == | |
| - | == | + | <references/> |
| - | + | __TOC__ | |
| + | </StructureSection> | ||
[[Category: Hexokinase]] | [[Category: Hexokinase]] | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
Revision as of 14:26, 29 September 2014
CRYSTAL STRUCTURE OF RECOMBINANT HUMAN BRAIN HEXOKINASE TYPE I COMPLEXED WITH GLUCOSE AND GLUCOSE-6-PHOSPHATE
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