. Here, one also finds that the two main contributions to the differences in ∆𝑈 𝑏𝑜𝑛𝑑𝑒𝑑 ‡ compared to the water reaction (Table ) originate from the Morse potential bond terms (~10 kcal/mol) and the torsional energies (~4 kcal/mol), while angle and improper terms have negligible contributions. Hence, both of the two enzymes enforce a more compact transition state than in water, which results in more favorable values of ∆𝑈 𝑏𝑜𝑛𝑑𝑒𝑑 ‡