1e1r
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BOVINE MITOCHONDRIAL F1-ATPASE INHIBITED BY MG2+ADP AND ALUMINIUM FLUORIDE
OverviewOverview
BACKGROUND: The globular domain of the membrane-associated F(1)F(o)-ATP, synthase complex can be detached intact as a water-soluble fragment known, as F(1)-ATPase. It consists of five different subunits, alpha, beta, gamma, delta and epsilon, assembled with the stoichiometry 3:3:1:1:1. In, the crystal structure of bovine F(1)-ATPase determined previously at 2.8 A, resolution, the three catalytic beta subunits and the three noncatalytic, alpha subunits are arranged alternately around a central alpha-helical, coiled coil in the gamma subunit. In the crystals, the catalytic sites, have different nucleotide occupancies. One contains the triphosphate form, of the nucleotide, the second contains the diphosphate, and the third is, unoccupied. Fluoroaluminate complexes have been shown to mimic the, transition state in several ATP and GTP hydrolases. In order to understand, more about its catalytic mechanism, F(1)-ATPase was inhibited with, Mg(2+)ADP and aluminium fluoride and the structure of the inhibited, complex was determined by X-ray crystallography. RESULTS: The structure of, bovine F(1)-ATPase inhibited with Mg(2+)ADP and aluminium fluoride, determined at 2.5 A resolution differs little from the original structure, with bound AMP-PNP and ADP. The nucleotide occupancies of the alpha and, beta subunits are unchanged except that both aluminium trifluoride and, Mg(2+)ADP are bound in the nucleotide-binding site of the beta(DP), subunit. The presence of aluminium fluoride is accompanied by only minor, adjustments in the surrounding protein. CONCLUSIONS: The structure appears, to mimic a possible transition state. The coordination of the, aluminofluoride group has many features in common with other, aluminofluoride-NTP hydrolase complexes. Apparently, once nucleotide is, bound to the catalytic beta subunit, no additional major structural, changes are required for catalysis to occur.
About this StructureAbout this Structure
1E1R is a Protein complex structure of sequences from Bos taurus with MG, PO4, ANP, ADP and AF3 as ligands. Active as Transferred entry: 3.6.3.14, with EC number 3.6.1.34 Known structural/functional Sites: and . Full crystallographic information is available from OCA.
ReferenceReference
Structure of bovine mitochondrial F(1)-ATPase inhibited by Mg(2+) ADP and aluminium fluoride., Braig K, Menz RI, Montgomery MG, Leslie AG, Walker JE, Structure. 2000 Jun 15;8(6):567-73. PMID:10873854
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