Reversible inhibition of butyrylcholinesterase with aromatic hydrocarbons.

Reversible inhibition of butyrylcholinesterase (acylcholine acylhydrolase, EC 3.1.1.8) with several aroma hydrocarbons was investigated and the results obtained were analyzed in terms of the hydrophobic interaction, making use of the solvent-water partition coefficients for the parameterization of the hydrophobic character of the ligand molecule. To obtain purely hydrophobic effects, the compounds incapable of specific solvation (hydrogen-bond formation) in water as well as in the hydrophobic phase were specially selected for the reaction series. Determination of the hydrophobic properties of the enzyme binding site allows further investigation into the other specificity-determining factors of the non-covalent complex formation step of butyrylcholinesterase-catalyzed reactions.