FIG 9.

(A) The proposed reaction mechanism of molinate hydrolase acting on docked molinate, with the catalytic metal and water molecules from the aligned structure of PuhB. The nucleophilic hydroxide is generated in a metal ion-dependent manner in concert with His215 acting as a general base. The leaving group is then protonated from a metal-coordinated water molecule stabilized by Lys209. The metal ion can act to stabilize the negative charge that develops at the carbonyl oxygen in the transition state. Docking was performed in AutoDock (44).