InterPro domain: IPR033732

The F-ATPase is found in bacterial plasma membranes, mitochondrial inner membranes and in chloroplast thylakoid membranes. It has also been found in the archaea Methanosarcina barkeri [ 1 ]. It uses a proton gradient to drive ATP synthesis and hydrolyzes ATP to build the proton gradient. The extrinsic membrane domain, F1, is composed of alpha, beta, gamma, delta and epsilon subunits with a stoichiometry of 3:3:1:1:1 [ 2 ]. There is a substrate-binding site on each of the alpha and beta subunits, those on the beta subunits being catalytic, while those on the alpha subunits are regulatory. The alpha and beta subunits form a cylinder that is attached to the central stalk. The alpha/beta subunits undergo a sequence of conformational changes leading to the formation of ATP from ADP, which are induced by the rotation of the gamma subunit, itself driven by the movement of protons through the F0 complex C subunit [ 3 ].

This entry represents the nucleotide-binding central domain of the F1-ATPase alpha subunit.

1. F0F1-ATPase genes from an archaebacterium, Methanosarcina barkeri. Biochem. Biophys. Res. Commun. 241, 427-33
2. Mechanism of the F(1)F(0)-type ATP synthase, a biological rotary motor. Trends Biochem. Sci. 27, 154-60
3. Understanding ATP synthesis: structure and mechanism of the F1-ATPase (Review). Mol. Membr. Biol. 20, 27-33