(Acetylcholine acetylhydrolase; EC 18.104.22.168)
Acetyl Cholinesterase (AChE) catalyzes the hydrolysis of acetylcholine as shown below:AChE
Actylcholine + H2O Choline + Acetic Acid
This enzyme is bound to cellular membranes and is believed to be associated with the conduction of nerve impulses. It has been isolated from various animal tissues, including the brain, lungs, and erythrocytes. A second cholinesterase is found in blood serum (butyryl cholinesterase; EC 22.214.171.124), which hydrolyzes butyrylcholine four times faster than acetylcholine. They are two distinct enzymes in terms of substrate specificity and pH optimum. The assay of these two enzymes is of diagnostic value in various liver diseases, malignancies and in pulmonary tuberculosis (Methods of Enzymatic Analysis, Bergmeyer, H.U. ed.,: Vol.2., 833, 1974, Academic Press, New York).