Fig. 8. (a) and (b) Correlations between τ_1/2^Q-vib and T, and ln k_f^Q-vib and 1/T for the rate determining step (St0-[1]^Ext → St0-[1]^Ext,‡ in Fig. 7(b) in Type (3) mechanism obtained from the TST method, compared with experiment.⁵τ_1/2^loss,T and k^loss,T = half-life and first-order rate constant for the loss of enzyme stability at 273 K;⁵τ_1/2^loss,UV and k^loss,UV = half-life and first-order rate constant for the loss of enzyme activity due to UV radiation at 365 nm;⁵τ_1/2^Q-vib and k_f^Q-vib = half-life and first-order rate constant for the rate-determining intermolecular proton transfer (St0-[1]^Ext → St0-[1]^Ext,‡) in Fig. 7(b).