The ATP-waiting conformation of rotating F1-ATPase revealed by single-pair fluorescence resonance energy transfer

Proc Natl Acad Sci U S A. 2003 Aug 5;100(16):9314-8. doi: 10.1073/pnas.1637860100. Epub 2003 Jul 22.

Abstract

F1-ATPase is an ATP-driven rotary motor in which a rod-shaped gamma subunit rotates inside a cylinder made of alpha3beta3 subunits. To elucidate the conformations of rotating F1, we measured fluorescence resonance energy transfer (FRET) between a donor on one of the three betas and an acceptor on gamma in single F1 molecules. The yield of FRET changed stepwise at low ATP concentrations, reflecting the stepwise rotation of gamma. In the ATP-waiting state, the FRET yields indicated a gamma position approximately 40 degrees counterclockwise (= direction of rotation) from that in the crystal structures of mitochondrial F1, suggesting that the crystal structures mimic a metastable state before product release.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / chemistry
  • Adenosine Triphosphate / chemistry*
  • Bacillus / enzymology
  • Crystallography, X-Ray
  • Dose-Response Relationship, Drug
  • Fluorescence Resonance Energy Transfer
  • Models, Biological
  • Models, Theoretical
  • Mutation
  • Protein Conformation
  • Proton-Translocating ATPases / chemistry*

Substances

  • Adenosine Triphosphate
  • Adenosine Triphosphatases
  • Proton-Translocating ATPases