Rotor: c-ring foot and γ stalkProtons (H⁺)ATP released from the headBovine ATP synthase at true scale (ruler: 1 tick = 1 nm). Eight c-subunits form the rotor ring, so one turn carries 8 protons from the intermembrane space below to the matrix above, and the three catalytic β lobes each release one ATP per turn: 8/3 ≈ 2.7 H⁺ per ATP. Above about 145 mV it makes ~100 ATP a second; lower the force and the same motor runs backwards, burning ATP to pump protons. Motion shown 120× slower.
8 H⁺每转（牛 c8 环）per turn (bovine c8 ring)3 ATP每转per turn~100 /s每个酶的 ATP 产率ATP per enzyme~145 mV停转/反转阈值stall / reversal threshold~65 kg人每天周转的 ATPATP a human turns over daily