Figure 12.

Construction of a model ratchet motor. (a) Beads 1, 2 and 10 are fixed, immobilizing one domain. Bead 64 can interact with the force centres (blue beads) on the filament. The filament can only slide along its direction. (b) The trajectory of bead 64 within one cycle. In the ligand-bound state s = 1, the bead comes close to the filament, establishes interactions, and moves it. In the second half of the cycle (s = 0), this bead is separated from the filament and moves back without holding it. Thus, the filament becomes progressively translocated after each cycle. Adapted from [38]. See also the electronic supplementary material, video S5. (Online version in colour.)