Interaction of quaternary aromatic isoquinoline alkaloids with acetylcholinesterase from Electrophorus electricus

Fluorescence data for the interaction of acetylcholinesterase (EC 3.1.1.7, ACHE) from Electrophorus electricus with berberine, 13-ethylberberine, coralyne, and chelerythrine have been presented. By a comparison with known inhibitors of acetylcholinesterase, tetramethylammonium and tacrine, the electrostatic interaction of quaternary alkaloids with the γ-anionic site of enzyme could be confirmed. During the interaction, two molecules of the ligand are bound to the molecule of the enzyme.