Proton-powered subunit rotation in single membrane-bound F0F1-ATP synthase.
Synthesis of ATP from ADP and phosphate, catalyzed by F(0)F(1)-ATP synthases, is the most abundant physiological reaction in almost any cell. F(0)F(1)-ATP synthases are membrane-bound enzymes that use the energy derived from an electrochemical proton gradient for ATP formation. We incorporated double-labeled F(0)F(1)-ATP synthases from Escherichia coli into liposomes and measured single-molecule fluorescence resonance energy transfer (FRET) during ATP synthesis and hydrolysis. The gamma subunit rotates stepwise during proton transport-powered ATP synthesis, showing three distinct distances to the b subunits in repeating sequences. The average durations of these steps correspond to catalytic turnover times upon ATP synthesis as well as ATP hydrolysis. The direction of rotation during ATP synthesis is opposite to that of ATP hydrolysis.
Diez
Manuel
M
Institut für Physikalische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 23 a, 79104 Freiburg, Germany.
Zimmermann
Boris
B
Börsch
Michael
M
König
Marcelle
M
Schweinberger
Enno
E
Steigmiller
Stefan
S
Reuter
Rolf
R
Felekyan
Suren
S
Kudryavtsev
Volodymyr
V
Seidel
Claus A M
CA
Gräber
Peter
P
D000255:Adenosine Triphosphate / Q000378:metabolism; D000266:Adenylyl Imidodiphosphate / Q000378:metabolism; D002384:Catalysis; D004735:Energy Transfer; D005453:Fluorescence; D006868:Hydrolysis; D006180:Proton-Translocating ATPases / Q000378:metabolism*; D011522:Protons
D011522:Protons; D000266:Adenylyl Imidodiphosphate; D000255:Adenosine Triphosphate; D006180:Proton-Translocating ATPases