FIGURE 7.

Loading rate of unbinding force. From force curves showing unbinding events the unbinding force F_i was plotted versus the loading rate r_i of every individual curve, with the latter being calculated by multiplying the effective spring constant with the pulling speed. The corresponding scatter plot thus shows the rupture force as a function of loading rate for all measured binding events (4624 events). From those data, k_off and x_β were determined to be 0.65 ± 0.02 s⁻¹ and 2.88 ± 0.03 nm, respectively. With the kinetic on-rate as determined above to 410.05 m⁻¹ s⁻¹, the dissociation constant K_D = k_off/k_on was calculated to be 1.6 mm.