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1dgk
From Proteopedia
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|PDB= 1dgk |SIZE=350|CAPTION= <scene name='initialview01'>1dgk</scene>, resolution 2.8Å | |PDB= 1dgk |SIZE=350|CAPTION= <scene name='initialview01'>1dgk</scene>, resolution 2.8Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand= | + | |LIGAND= <scene name='pdbligand=ADP:ADENOSINE-5'-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=GLC:GLUCOSE'>GLC</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene> |
| - | |ACTIVITY= [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] | + | |ACTIVITY= <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> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1cza|1CZA]], [[1hkb|1HKB]], [[1hkc|1HKC]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1dgk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1dgk OCA], [http://www.ebi.ac.uk/pdbsum/1dgk PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1dgk RCSB]</span> | ||
}} | }} | ||
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==Overview== | ==Overview== | ||
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. | 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. | ||
| - | |||
| - | ==Disease== | ||
| - | Known disease associated with this structure: Hemolytic anemia due to hexokinase deficiency OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=142600 142600]] | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: Kirby, C.]] | [[Category: Kirby, C.]] | ||
[[Category: Liu, X.]] | [[Category: Liu, X.]] | ||
| - | [[Category: ADP]] | ||
| - | [[Category: GLC]] | ||
| - | [[Category: PO4]] | ||
[[Category: brain hexokinase]] | [[Category: brain hexokinase]] | ||
[[Category: mammalian hexokinase 1]] | [[Category: mammalian hexokinase 1]] | ||
[[Category: sugar kinase]] | [[Category: sugar kinase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 19:41:16 2008'' |
Revision as of 16:41, 30 March 2008
| |||||||
| , resolution 2.8Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , | ||||||
| Activity: | Hexokinase, with EC number 2.7.1.1 | ||||||
| Related: | 1CZA, 1HKB, 1HKC
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
MUTANT MONOMER OF RECOMBINANT HUMAN HEXOKINASE TYPE I WITH GLUCOSE AND ADP IN THE ACTIVE SITE
Overview
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.
About this Structure
1DGK is a Single protein structure of sequence from Homo sapiens. The following page contains interesting information on the relation of 1DGK with [The Glycolytic Enzymes]. Full crystallographic information is available from OCA.
Reference
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
Page seeded by OCA on Sun Mar 30 19:41:16 2008
