A structure-based model for the synthesis and hydrolysis of ATP by F1-ATPase.
Many essential functions of living cells are performed by nanoscale protein motors. The best characterized of these is F(o)F1-ATP synthase, the smallest rotary motor. This rotary motor catalyzes the synthesis of ATP with high efficiency under conditions where the reactants (ADP, H2PO4(-)) and the product (ATP) are present in the cell at similar concentrations. We present a detailed structure-based kinetic model for the mechanism of action of F1-ATPase and demonstrate the role of different protein conformations for substrate binding during ATP synthesis and ATP hydrolysis. The model shows that the pathway for ATP hydrolysis is not simply the pathway for ATP synthesis in reverse. The findings of the model also explain why the cellular concentration of ATP does not inhibit ATP synthesis.
Gao
Yi Qin
YQ
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Yang
Wei
W
Karplus
Martin
M
D000255:Adenosine Triphosphate / Q000138:chemical synthesis* / Q000378:metabolism*; D002384:Catalysis; D018360:Crystallography, X-Ray; D006868:Hydrolysis; D007700:Kinetics; D008956:Models, Chemical; D008958:Models, Molecular; D008962:Models, Theoretical; D020409:Molecular Motor Proteins / Q000737:chemistry / Q000378:metabolism*; D009154:Mutation; D036103:Nanotechnology; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D021122:Protein Subunits; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012399:Rotation; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D013816:Thermodynamics; D019415:Torque
D020409:Molecular Motor Proteins; D021122:Protein Subunits; D000255:Adenosine Triphosphate; D006180:Proton-Translocating ATPases