ATP synthase
Mitochondrial F0F1 enzyme that synthesises ATP by harnessing the proton gradient across the inner mitochondrial membrane.
For laboratory and research use only — not for human consumption.
ATP synthase (F0F1-ATPase, Complex V) is the rotary molecular machine in the inner mitochondrial membrane that synthesises adenosine triphosphate (ATP) from ADP and inorganic phosphate, powered by the proton-motive force generated by the electron-transport-chain Complexes I, III, and IV. The enzyme comprises two rotational subassemblies: F0 (membrane-embedded, conducting protons through the c-ring and driving rotation) and F1 (matrix-side, containing three catalytic β-subunits in the α₃β₃ hexamer where ATP is synthesised through the binding-change mechanism elucidated by Boyer). Each full rotation of the central γ-shaft drives the synthesis of three ATP molecules. ATP synthase is the most efficient molecular machine known, with near-100% mechano-chemical coupling under physiological conditions. Inherited and acquired ATP-synthase dysfunction underlies mitochondrial disease, and acquired uncoupling between proton transport and ATP synthesis contributes to the ageing cellular phenotype and metabolic dysfunction. In peptide research, ATP synthase is the principal energetic readout of mitochondrial-peptide effect: SS-31 (elamipretide) binds cardiolipin in the inner mitochondrial membrane and is proposed to stabilise the cristae architecture that maintains ATP-synthase organisation; MOTS-c and Humanin (mitochondrial-derived peptides) regulate mitochondrial biogenesis and bioenergetics upstream of ATP-synthase activity. ATP/ADP ratio, oxygen consumption rate, and ATP-synthase enzymatic assay are standard endpoints in mitochondrial peptide research.