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Updated: Aug 9, 2026

Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase
Published on: December 19, 2011
Phosphonylation mechanisms of sarin and acetylcholinesterase: a model DFT study
Jing Wang1, Jiande Gu, Jerzy Leszczynski
1Computational Center for Molecular Structure and Interactions, Department of Chemistry, Jackson State University, Jackson, Mississippi 39217, USA.
Abstract:
Potential energy surfaces for the phosphonylation of sarin and acetylcholinesterase (AChE) have been theoretically studied at the B3LYP/6-311G(d,p) level of theory. The obtained results show that the phosphonylation process involves a two-step addition-elimination mechanism, with the first step (addition process) being the rate-determining step, while by comparison, the ensuing steps are very rapid. Stable trigonal bipyramidal intermediates are formed in the studied pathways. It is also revealed that the catalytic triad of acetylcholinesterase plays the catalytic role in the reaction by speeding up the phosphonylation process, as it does in the acylation reaction of ACh and AChE. The effect of aqueous solvation was accounted for via the polarizable continuum model. It is concluded that the enzymatic reaction here is influenced strongly by the solvent environment.
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