ATP Synthase Motor Components: Proposal and Animation of Two Dynamic Models for Stator Function

• Published in: Biochemical and biophysical research communications Vol. 287; no. 4; pp. 801 - 807
• Main Authors: Blum, David J., Ko, Young Hee, Hong, Sangjin, Rini, David A., Pedersen, Peter L.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 05.10.2001
• Subjects: Adenosine Triphosphate - metabolism; ATP synthase; ATP synthesis; bioenergetics; Computer Simulation; F1-ATPase; mitochondria; Models, Molecular; molecular machines; Molecular Motor Proteins - metabolism; molecular motors; nanomotors; nanotechnology; oxidative phosphorylation; Protein Binding; Protein Conformation; Protein Structure, Quaternary; Protein Subunits; Proton-Translocating ATPases - chemistry; Proton-Translocating ATPases - metabolism; F1-ATPase; ATP synthase; bioenergetics; molecular machines; mitochondria; nanomotors; ATP synthesis; nanotechnology; molecular motors; oxidative phosphorylation
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1006/bbrc.2001.5634

Recent research indicates that ATP synthases (F0F1) contain two distinct nanomotors, one an electrochemically driven proton motor contained within F0 that drives an ATP hydrolysis-driven motor (F1) in reverse during ATP synthesis. This is depicted in recent models as involving a series of events in which each of the three αβ pairs comprising F1 is induced via a centrally rotating subunit (γ) to undergo the sequential binding changes necessary to synthesize ATP (binding change mechanism). Stabilization of this rotary process (i.e., to minimize “wobble” of F1) is provided in current models by a peripheral stalk or “stator” that has recently been shown to extend from near the bottom of the ATP synthase molecule to the very top of F1. Although quite elegant, these models envision the stator as fixed during ATP synthesis, i.e., bound to only a single αβ pair. This is despite the fact that the binding change mechanism views each αβ pair as going through the same sequential order of conformational changes which demonstrate a chemical equivalency among them. For this reason, we propose here two different dynamic models for stator function during ATP synthesis. Both models have been designed to maintain chemical equivalency among the three αβ pairs during ATP synthesis and both have been animated.