1ngd
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STRUCTURAL BASIS OF THE 70-KILODALTON HEAT SHOCK COGNATE PROTEIN ATP HYDROLYTIC ACTIVITY, II. STRUCTURE OF THE ACTIVE SITE WITH ADP OR ATP BOUND TO WILD TYPE AND MUTANT ATPASE FRAGMENT
OverviewOverview
The ATPase fragment of the bovine 70-kDa heat shock cognate protein is an, attractive construct in which to study its mechanism of ATP hydrolysis., The three-dimensional structure suggests several residues that might, participate in the ATPase reaction. Four acidic residues (Asp-10, Glu-175, Asp-199, and Asp-206) have been individually mutated to both the cognate, amine (asparagine/glutamine) and to serine, and the effects of the, mutations on the kinetics of the ATPase activity (Wilbanks, S. M., DeLuca-Flaherty, C., and McKay, D. B. (1994) J. Biol. Chem. 269, 12893-12898) and the structure of the mutant ATPase fragments have been, determined, typically to approximately 2.4 A resolution. Additionally, the, structures of the wild type protein complexed with MgADP and Pi, MgAMPPNP, (5'-adenylyl-beta, gamma-imidodiphosphate) and CaAMPPNP have been refined, to 2.1, 2.4, and 2.4 A, respectively. Combined, these structures provide, models for the prehydrolysis, MgATP-bound state and the post-hydrolysis, MgADP-bound state of the ATPase fragment. These models suggest a pathway, for the hydrolytic reaction in which 1) the gamma phosphate of bound ATP, reorients to form a beta, gamma-bidentate phosphate complex with the Mg2+, ion, allowing 2) in-line nucleophilic attack on the gamma phosphate by a, H2O molecule or OH- ion, with 3) subsequent release of inorganic, phosphate.
About this StructureAbout this Structure
1NGD is a Single protein structure of sequence from Bos taurus with MG, PO4 and ADP as ligands. Active as Adenosinetriphosphatase, with EC number 3.6.1.3 Full crystallographic information is available from OCA.
ReferenceReference
Structural basis of the 70-kilodalton heat shock cognate protein ATP hydrolytic activity. II. Structure of the active site with ADP or ATP bound to wild type and mutant ATPase fragment., Flaherty KM, Wilbanks SM, DeLuca-Flaherty C, McKay DB, J Biol Chem. 1994 Apr 29;269(17):12899-907. PMID:8175707
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