Figure 6.

Energies for the O-ester and S-ester substrates calculated with different, fixed distances between the oxygen from water and the carbonyl carbon. Conformations of these minimized ester substrates are considerably different; (b) O-ester with the associated water molecule close to the carbonyl group; (c) the S-ester prefers a different location in the active site with a large distance between the water molecule and the carbonyl group. Ca²⁺ (dark gray), P (pink), O (red), N (blue), S (yellow), C (light gray) and H (white). Reproduced with permission from [44].