ATP synthase: what we know about ATP hydrolysis and what we do not know about ATP synthesis.
In ATP synthase, X-ray structures, demonstration of ATP-driven gamma-subunit rotation, and tryptophan fluorescence techniques to determine catalytic site occupancy and nucleotide binding affinities have resulted in pronounced progress in understanding ATP hydrolysis, for which a mechanism is presented here. In contrast, ATP synthesis remains enigmatic. The molecular mechanism by which ADP is bound in presence of a high ATP/ADP concentration ratio is a fundamental unknown; similarly P(i) binding is not understood. Techniques to measure catalytic site occupancy and ligand binding affinity changes during net ATP synthesis are much needed. Relation of these parameters to gamma-rotation is a further goal. A speculative model for ATP synthesis is offered.
Weber
J
J
Department of Biochemistry and Biophysics, Box 712, University of Rochester Medical Center, Rochester, NY 14642, USA.
Senior
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AE
D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000096:biosynthesis / Q000378:metabolism*; D006868:Hydrolysis; D020409:Molecular Motor Proteins / Q000737:chemistry; D011485:Protein Binding; D006180:Proton-Translocating ATPases / Q000737:chemistry* / Q000378:metabolism
D020409:Molecular Motor Proteins; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D006180:Proton-Translocating ATPases