FIGURE 3.

Quantitative free-energy profile for the group I reaction with wild-type and (C₁₁₁·G₂₀₉) ribozyme. The free-energy profiles were calculated at 30°C (pH 7.2) and for a standard state of 1 mM G and GA. In the case of the reaction with wild-type ribozyme (continuous line), the reaction described by (k_cat/K_m)^G is from (E·S)_c + G and the transition state for the chemical step (‡). For the (C₁₁₁·G₂₀₉) mutant (broken line), the reaction described by (k_cat/K_m)^G is from (E·S)_o + G, and the transition state of the chemical step (‡), and thus includes the additional barrier for docking. The free-energy profile was calculated as outlined in the Materials and Methods using the values listed in Table 6 ▶.