Phosphodiester hydrolysis computed for cluster models of enzymatic active sites

摘要: Computation of phosphodiester hydrolysis in different models with one or two metal ions, representing typical active site architectures nucleases, reveals an associative mechanism to be favorable all the cases studied this work. Direct attack nucleophilic water molecule proton transfer phosphate group is facilitated by extra positive charge as provided a ion located at positively charged histidine residue, whereas no such contribution can observed on leaving departure. A major catalytic effect found from histidine–aspartate cluster. Attack thus generated hydroxide just sufficiently stabilized ions allow subsequent P–O bond dissociation.