9-Tempoylmiinoacridine: A Spin-Labeled,Fluorescent Probe of Acetylcholinesterase

Abstract

9-tenpoylaminoacridine, a new spin-labeled probe of acetylcholinesterase, binds reversibly to the aggregating forms of this enzyme obtained from Electrophorus electricus.

The decrease in EPR signal amplitude upon binding is used to calculate a dissociation constant of 0.37 μM for this interaction. The calculated equivalent weight per binding site of 98,400 corresponds to approximately one binding site per enzyme subunit, based on the proposed structure of the enzyme.