Rotary movements within the ATP synthase do not constitute an obligatory element of the catalytic mechanism.
After a brief history of the proposals for the mechanism of the ATP synthase, the main experimental arguments for a rotational mechanism of catalysis are analyzed and on the basis of this analysis it is concluded that no evidence has been provided for rotation as an obligatory element of the catalytic mechanism. On the other hand, the experimental evidence in favor of a two-sites catalytic mechanism, derived from various approaches and not compatible with a three-sites rotary mechanism, appear to be very solid. Finally a brief characterization of the various nucleotide binding sites is provided and a suggestion is made how the enzyme has evolutionarily developed from a rotating machine into an asymmetrical device for energy conservation.
Berden
Jan A
JA
Swammerdam Institute for Life Sciences, BioCentrum, University of Amsterdam, Plantage Muidergracht 12, 1018 TV, Amsterdam, The Netherlands. jan.berden@science.uva.nl
D025181:ATP Synthetase Complexes / Q000737:chemistry* / Q000502:physiology; D000255:Adenosine Triphosphate / Q000737:chemistry; D001665:Binding Sites; D001696:Biomechanical Phenomena; D002384:Catalysis; D020134:Catalytic Domain; D002736:Chloroplasts / Q000201:enzymology; D003432:Cross-Linking Reagents / Q000494:pharmacology; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000378:metabolism; D006868:Hydrolysis; D007700:Kinetics; D008954:Models, Biological; D006180:Proton-Translocating ATPases / Q000737:chemistry*
D003432:Cross-Linking Reagents; D000255:Adenosine Triphosphate; D025181:ATP Synthetase Complexes; D006180:Proton-Translocating ATPases