Contribution of charged side chains, Mg2+, and solvent exclusion to enzymatic beta-decarboxylation of alpha-keto acids

Classical electrostatic calculations are applied to the study of the origin of enzymatic rate enhancement of one class of biochemical carbon-carbon bond cleavage reactions. A model based on the three-dimensional structure of magnesium(II) isocitrate joined to isocitrate dehydrogenase is used for the charge distribution in the ground and transition states in the decarboxylation reaction.