In which direction does ATP synthase rotate?

Question

I heard about the rotation of ATP synthase in a biochemistry course. The professor said it will rotate counterclockwise. Is that true? If so, what mechanism defines its direction?

Answer 1

Yes, the ATP synthase rotates in a counterclockwise direction. This was observed in an experiment from the laboratory of Masasuke Yoshida and was published in Nature in 1997¹. The rotation is driven by an influx of H⁺ down the proton gradient and the proteins different affinities for the reactants and their products at different times during the reaction.

1.) Hiroyuki Noji, Ryohei Yasuda, Masasuke Yoshida & Kazuhiko Kinosita Jr. (1997) Direct observation of the rotation of F1-ATPase. Nature, 386, 299 - 302.