1NGB

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

Summary for 1NGB

• Entry DOI: 10.2210/pdb1ngb/pdb
• Descriptor: HEAT-SHOCK COGNATE 70 kD PROTEIN, MAGNESIUM ION, PHOSPHATE ION, ... (5 entities in total)
• Functional Keywords: hydrolase(acting on acid anhydrides)
• Biological source: Bos taurus (cattle)
• Cellular location: Cytoplasm (By similarity): P19120
• Total number of polymer chains: 1
• Total formula weight: 43058.53

Authors

Flaherty, K.M.,Wilbanks, S.M.,Deluca-Flaherty, C.,Mckay, D.B. (deposition date: 1994-05-17, release date: 1994-08-31, Last modification date: 2024-02-14)

Primary citation

Flaherty, K.M.,Wilbanks, S.M.,DeLuca-Flaherty, C.,McKay, D.B.
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.
J.Biol.Chem., 269:12899-12907, 1994

PubMed Abstract: 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.

PubMed: 8175707

Experimental method

X-RAY DIFFRACTION (2.18 Å)