title: A reciprocating motion-driven rotation mechanism for the ATP synthase.
abstract: The ATP synthase (having a typical subunit composition of α3β3γδεab2c8-15) employs an intriguing rotary mechanism for the generation of ATP from ADP and Pi, using energy stored in a transmembrane proton gradient. The conventional rotary model, although being generally accepted, remains difficult to explain certain experimental observations. Here we propose an alternative rotary model for the ATP synthase such that what rotates is the catalytic α3β3 cylinder rather than the central stalk and the membrane-embedded c-ring. Specifically, the membrane translocation of protons would induce a cycled conformational change in the c-ring, leading to a reciprocating motion of the attached central stalk, which in turn drives the unidirectional rotation of the α3β3 cylinder. Such a reciprocating motion-driven rotation mechanism is somehow analogous to the working mechanism of a retractable click ballpoint pen. Our new model not only explains the experimental observations that have been difficult to reconcile with the conventional model but also avoids its theoretical illogicality.
authors.affiliation: State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, 100871, China.
authors.forename: Jiafeng
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, 100871, China. fuxinmiao@pku.edu.cn.|Center for Protein Science, Peking University, Beijing, 100871, China. fuxinmiao@pku.edu.cn.
authors.forename: Xinmiao
authors.initials: X
authors.lastname: Fu
authors.affiliation: State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, 100871, China. changzy@pku.edu.cn.|Center for Protein Science, Peking University, Beijing, 100871, China. changzy@pku.edu.cn.
authors.forename: Zengyi
authors.initials: Z
authors.lastname: Chang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D017124:Conserved Sequence; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009038:Motion; D054730:Protein Interaction Domains and Motifs; D020836:Protein Structure, Quaternary; D021122:Protein Subunits; D018892:Proton-Motive Force; D006180:Proton-Translocating ATPases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D012399:Rotation; D017386:Sequence Homology, Amino Acid
chemical_list: D021122:Protein Subunits; D006180:Proton-Translocating ATPases
keywords: ATP synthase; rotary model; rotational catalysis