Engineering rotor ring stoichiometries in the ATP synthase. Proc Natl Acad Sci U S A 2012 Jun 19;109(25):E1599-608
Date
05/26/2012Pubmed ID
22628564Pubmed Central ID
PMC3382517DOI
10.1073/pnas.1120027109Scopus ID
2-s2.0-84862583909 (requires institutional sign-in at Scopus site) 85 CitationsAbstract
ATP synthase membrane rotors consist of a ring of c-subunits whose stoichiometry is constant for a given species but variable across different ones. We investigated the importance of c/c-subunit contacts by site-directed mutagenesis of a conserved stretch of glycines (GxGxGxGxG) in a bacterial c(11) ring. Structural and biochemical studies show a direct, specific influence on the c-subunit stoichiometry, revealing c(<11), c(12), c(13), c(14), and c(>14) rings. Molecular dynamics simulations rationalize this effect in terms of the energetics and geometry of the c-subunit interfaces. Quantitative data from a spectroscopic interaction study demonstrate that the complex assembly is independent of the c-ring size. Real-time ATP synthesis experiments in proteoliposomes show the mutant enzyme, harboring the larger c(12) instead of c(11), is functional at lower ion motive force. The high degree of compliance in the architecture of the ATP synthase rotor offers a rationale for the natural diversity of c-ring stoichiometries, which likely reflect adaptations to specific bioenergetic demands. These results provide the basis for bioengineering ATP synthases with customized ion-to-ATP ratios, by sequence modifications.
Author List
Pogoryelov D, Klyszejko AL, Krasnoselska GO, Heller EM, Leone V, Langer JD, Vonck J, Müller DJ, Faraldo-Gómez JD, Meier TAuthor
Vanessa Leone PhD Assistant Professor in the Biophysics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
ATP Synthetase ComplexesAdenosine Triphosphate
Electrophoresis, Polyacrylamide Gel
Microscopy, Atomic Force
Microscopy, Electron
Models, Molecular
Mutation
Protein Conformation
Proteolipids
Surface Plasmon Resonance
