InterPro domain: IPR007648

ATP synthase inhibitor prevents the enzyme from switching to ATP hydrolysis during collapse of the electrochemical gradient, for example during oxygen deprivation [ 1 ] ATP synthase inhibitor forms a one to one complex with the F1 ATPase, possibly by binding at the alpha-beta interface. It is thought to inhibit ATP synthesis by preventing the release of ATP [ 2 ]. The minimum inhibitory region for bovine inhibitor ( P01096 ) is from residues 39 to 72 [ 3 ]. The inhibitor has two oligomeric states, dimer (the active state) and tetramer. At low pH , the inhibitor forms a dimer via antiparallel coiled coil interactions between the C-terminal regions of two monomers. At high pH, the inhibitor forms tetramers and higher oligomers by coiled coil interactions involving the N terminus and inhibitory region, thus preventing the inhibitory activity [ 3 ].

1. Homologous and heterologous inhibitory effects of ATPase inhibitor proteins on F-ATPases. J. Biol. Chem. 277, 41334-41
2. The ATPase inhibitor protein from bovine heart mitochondria: the minimal inhibitory sequence. Biochemistry 35, 15618-25