New Inhibitors of the Peripheral Site in Acetycholinesterase that Specifically Block Organophosphorylation

Abstract

Acetylcholinesterase (AChE) hydrolyzes its physiological substrate acetylcholine at one of the highest known catalytic rates. Little is known about how the peripheral site contributes to the catalytic mechanism of the enzyme. Our studies provide new information about enzyme mechanisms and indicate strategies for designing drugs that defend AChE against inactivation by toxic organophosphates (Ops). We have introduced and confirmed a nonequilibrium analysis and steric blockade model for AChE inhibition by small peripheral site ligands. Additionally, we have examined the effect of known AChE peripheral site inhibitors with OPs to determine what properties may be useful in finding ways to prevent organophosphorylation. Analyses with known AChE peripheral site ligands and site-specific mutants of the enzyme have revealed that the physiological role of the peripheral site is to optimize activity of AChE by loading the enzyme with acetylcholine at low substrate concentrations. In addition to our biochemical studies, we have synthesized and screened new AChE specific ligands based on the structure of known peripheral site peptide ligands. These novel compounds display specificity for the AChE peripheral site and will serve as initial structures for the development of peripheral site ligands that will specifically block OP inactivation of AChE.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1999
Accession Number
ADB251342

Entities

People

  • Terrone L. Rosenberry

Organizations

  • Mayo Clinic

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  • Biomedical

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  • Acetylcholinesterases
  • Biochemistry
  • Biology
  • Chemical Analysis
  • Chemical Synthesis
  • Chemical Warfare Agents
  • Chemistry
  • Crystal Structure
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  • Mass Spectrometry
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