Mechanism and Stereochemistry of the Activation of (2S)- and (2R)-Serine O-Sulfate as Suicide Inhibitors for Escherichia coli Glutamic Acid Decarboxylase
E. coli glutamic acid decarboxylase is inactivated by both enantiomers of the suicide inhibitor serine O-sulfate; inactivation by the (2S)-enantiomer involves Cα-H bond cleavage while inactivation by the (2R)-isomer involves Cα-decarboxylation.Both processes occur on the 4'-Re-face of the coenzyme, the opposite face to that utilised in physiological decarboxylation.