As protons move back into the mitochondria, they must pass through as ATPase. For any transported species which is uncharged, the free energy change is related to the concentration of the species. In this calculation, no consideration is made of the charge of the species. Mitchell proposed that electron transport generates the proton-motive force. The F o component looks like the stalk of a mushroom.
F o is a proton channel that spans the inner mitochondrial membrane.
Multiple copies of chain c appear to form the channel for proton movement. Oligomycin is an antibiotic that blocks ATP synthesis by interfering with the ATP synthase. F 1 consists of three alpha-beta dimers and one copy each of gamma , sigma and epsilon subunits. The molecular weight of F 1 is approximately 378 kD, and the diameter of the component is approximately 85 Angstroms. The exact mechanism of catalysis by ATP synthase is not well established.