The ATP-waiting conformation of rotating F1-ATPase revealed by single-pair fluorescence resonance energy transfer.
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.
Yasuda
Ryohei
R
Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA. yasuda@cshl.org
Masaike
Tomoko
T
Adachi
Kengo
K
Noji
Hiroyuki
H
Itoh
Hiroyasu
H
Kinosita
Kazuhiko
K
D000251:Adenosine Triphosphatases / Q000737:chemistry; D000255:Adenosine Triphosphate / Q000737:chemistry*; D001407:Bacillus / Q000201:enzymology; D018360:Crystallography, X-Ray; D004305:Dose-Response Relationship, Drug; D031541:Fluorescence Resonance Energy Transfer; D008954:Models, Biological; D008962:Models, Theoretical; D009154:Mutation; D011487:Protein Conformation; D006180:Proton-Translocating ATPases / Q000737:chemistry*
D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D006180:Proton-Translocating ATPases