ATP synthase is a large molecular machine that converts the energy in an electrochemical gradient into the bond energy stored in ATP.

Which of the following events are required for the synthesis of ATP?

Choose one or more:

A. movement of protons down their gradient through ATP synthase

B. conformational changes of the F1 ATPase

C. binding of ATP to an empty F1 ATPase subunit

D. rotation of the rotor in the membrane