The partial purification and properties of a cholinesterase from Blatella germanica L.

Abstract

A purified preparation of cholinesterase was obtained from Blatella germanica. The overall purification was 40-fold and the yield 32%. The enzyme has a high affinity for acetylcholine and is inhibited by high concentrations of this and analogous esters. Various salts activate the enzyme at high concentrations of acetylcholine and under some circumstances inhibit at low substrate concentrations. The enzyme hydrolyses phenyl and triglyceryl esters as well as choline esters. Esters of acetic acid and propionic acid are hydrolysed much more rapidly than those of butyric acid. The enzyme showed optimum activity to acetylcholine and the acetyl and propionyl esters of phenol over a wide pH range. The properties of the enzyme are characteristic of the type of cholinesterases frequently associated with nervous tissues and are compared with those reported for cholinesterases from insect and other sources.