Cholesterol esterase (CE) is a reversible enzyme that can hydrolyze or synthesize fatty acid esters of cholesterol and other sterols. Hydrolysis of water insoluble long chain fatty acid esters requires bile salt activation. Hydrolysis of water soluble esters of short chain fatty acids and lysophospholipids does not require activation by bile salts. It also hydrolyzes tri-, di-, and mono-acylglycerols, phospholipids, lysophospholipids, and ceramides. The enzyme may have multiple functions in lipid and lipoprotein metabolism, as well as in atherosclerosis. Its molecular mass is approximately 129 kDa and the optimum pH range is 7.0-9.0. The enzyme is activated by cholic acid, glycocholic acid, BSA, Mg2+ and 0.3% (v/v) ? X-100. Ag+, Hg2+ and ionic detergents inhibit the activity of the enzyme.
