|Title||Structure of bovine mitochondrial F(1)-ATPase with nucleotide bound to all three catalytic sites: implications for the mechanism of rotary catalysis.|
|Publication Type||Journal Article|
|Year of Publication||2001|
|Authors||Menz, RI, Walker, JE, Leslie, AG|
|Date Published||2001 Aug 10|
|Keywords||Adenosine Diphosphate, Adenosine Triphosphate, Allosteric Regulation, Aluminum Compounds, Animals, Binding Sites, Catalysis, Cattle, Crystallography, X-Ray, Enzyme Inhibitors, Fluorides, Hydrolysis, Mitochondria, Models, Biological, Models, Molecular, Nucleotides, Protein Structure, Quaternary, Protein Structure, Tertiary, Protein Subunits, Proton-Translocating ATPases, Rotation, Structure-Activity Relationship, Sulfates|
The crystal structure of a novel aluminium fluoride inhibited form of bovine mitochondrial F(1)-ATPase has been determined at 2 A resolution. In contrast to all previously determined structures of the bovine enzyme, all three catalytic sites are occupied by nucleotide. The subunit that did not bind nucleotide in previous structures binds ADP and sulfate (mimicking phosphate), and adopts a "half-closed" conformation. This structure probably represents the posthydrolysis, pre-product release step on the catalytic pathway. A catalytic scheme for hydrolysis (and synthesis) at physiological rates and a mechanism for the ATP-driven rotation of the gamma subunit are proposed based on the crystal structures of the bovine enzyme.