1dgk
From Proteopedia
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MUTANT MONOMER OF RECOMBINANT HUMAN HEXOKINASE TYPE I WITH GLUCOSE AND ADP IN THE ACTIVE SITE
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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.
Disease
Known disease associated with this structure: Hemolytic anemia due to hexokinase deficiency OMIM:[142600]
About this Structure
1DGK is a Single protein structure of sequence from Homo sapiens with , and as ligands. The following page contains interesting information on the relation of 1DGK with [The Glycolytic Enzymes]. Active as Hexokinase, with EC number 2.7.1.1 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 Fri Feb 15 15:39:43 2008
