FIGURE 3.

Relationship between association and dissociation rate constants and φ-values for apparent two-state systems. Shown are energy diagrams (first column), observed association rate constants under pseudo-first order conditions (middle column), and observed dissociation rate constants (third column) for wild-type IDP (blue) and mutant IDP (red). A, φ = 1, i.e. native interactions are formed in the transition state. k_on is lower, and k_off is unchanged. B, 0 < φ <1 structure is partially formed, resulting in changes in both k_on and k_off. C, φ = 0, residue is as unstructured at the transition state as in the unbound state. k_on is unchanged, and k_off is increased. The rate constants k_on and k_off are controlled by energy barrier sizes (first column), and are determined from straight-line gradients in association mixing experiments (second column) and from high concentration asymptotes in out-competition dissociation mixing experiments (third column), respectively.