Purification and characterization of a carboxyl ester hydrolase from human pancreatic juice

A carboxyl ester hydrolase has been purified 20-fold from human pancreatic juice. It is a glycoprotein with a molecular weight of 100 000. It contains 9% neutral and amino carbohydrates and the amino acid composition is characterized by a high content of proline residue (12.7%). The enzyme catalyzes the hydrolysis of p-nitrophenylacetate and the activity increases in the presence of biliary salts; V is not modified but Km is decreased 10 times by addition of biliary salts. The enzyme migrates on Sephadex G-200 as a protein with a molecular weight of 300 000. This behaviour does not seem to be due to a polymerization but to a peculiar configuration of the enzyme.