Movie S2.

Trajectory of KSID40N with ionized Tyr57 from the AI-PIMD simulation. Because the six path integral beads used in the simulation are equivalent, the trajectory is shown for one bead. Frequent proton transfer can be observed in the trajectory. Green, red, and white represent carbon, oxygen, and hydrogen atoms, respectively. The three residues shown are (Left) Tyr16, (Right) Tyr32, and (Upper) Tyr57. The protein environment is also included.