[Skip to Content](https://www.sigmaaldrich.com#main-content) [![MilliporeSigma](https://www.sigmaaldrich.com/static/logos/purple/millipore_sigma.svg)](https://www.sigmaaldrich.com/US/en) Products Cart0 USEN Products [Login / Register](https://www.sigmaaldrich.com/oidc-sign-in) [Order Lookup](https://www.sigmaaldrich.com/US/en/order-lookup) [Quick Order](https://www.sigmaaldrich.com/US/en/quick-order) Cart0 [Home](https://www.sigmaaldrich.com/US/en)[Enzyme Activity Assays](https://www.sigmaaldrich.com/US/en/applications/protein-biology/enzyme-activity-assays)Cholesterol Esterification # Cholesterol Esterification To more efficiently transport both dietary and synthesized cholesterol, it is converted to cholesteryl esters. Free cholesterol can be taken up by lipoproteins, but is confined to the outer surface of the particle. By converting cholesterol to cholesteryl esters more cholesterol can be packaged into the interior of lipoproteins. This vastly increases the capacity of lipoproteins, allowing for more efficient cholesterol transport through the blood stream. ![Lecithin:Cholesterol acyltransferase (LCAT) is found in peripheral tissues and utilizes phosphatidylcholine as the source of acyl chains.](https://www.sigmaaldrich.com/content/dam/cms-commons/sigmaaldrich/marketing/global/images/technical-documents/articles/protein-biology/enzyme-activity-assays/lecithin.jpg "Lecithin:Cholesterol acyltransferase (LCAT) is found in peripheral tissues and utilizes phosphatidylcholine as the source of acyl chains.") __Figure 1.__Lecithin:Cholesterol acyltransferase (LCAT) is found in peripheral tissues and utilizes phosphatidylcholine as the source of acyl chains. Distinct enzymes catalyze the cholesterol to cholesteryl ester conversion depending on the location of the reaction. The conversion of cholesterol to cholesteryl ester is catalyzed predominantly by lecithin:cholesterol acyltransferase (LCAT) in the peripheral tissues (__Figure 1__). In the lumen, dietary cholesterol absorbed by enterocytes is esterified by acyl-coenzyme A: cholesterol acyltransferase 2 (ACAT2), which is found in both the intestine and liver (__Figure 2__). ACAT1 is found in all tissues. LCAT and ACAT also differ in the sources they use for the acyl chains. LCAT uses phosphatidylcholine while ACAT uses acyl-CoA. Inhibiting these enzymes is one way of lowering the circulating lipids in plasma. ![Acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT2) is found in the liver and intestine, and utilizes acyl-CoA as the source of acyl chains.](https://www.sigmaaldrich.com/content/dam/cms-commons/sigmaaldrich/marketing/global/images/technical-documents/articles/protein-biology/enzyme-activity-assays/acyl.jpg "Acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT2) is found in the liver and intestine, and utilizes acyl-CoA as the source of acyl chains.") __Figure 2.__Acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT2) is found in the liver and intestine, and utilizes acyl-CoA as the source of acyl chains. ## Materials Sorry, an unexpected error has occurred Response not successful: Received status code 500 __Related Articles__ - [Enzymatic Assay of Cathepsin B](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/protein-biology/enzyme-activity-assays/enzymatic-assay-of-cathepsin-b) - [Bioluminescent Firefly Luciferase Assays](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/cell-culture-and-cell-culture-analysis/imaging-analysis-and-live-cell-imaging/firefly-luciferase-assays) - [How to Work with Enzymes Supplied as Ammonium Sulfate Suspensions](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/protein-biology/enzyme-activity-assays/ammonium-sulfate-suspensions) - [Aprotinin](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/protein-biology/enzyme-activity-assays/aprotinin-monograph) - [Enzymatic Method for Determining Branched Chain Amino Acids (BCAA Assay)](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/protein-biology/enzyme-activity-assays/branched-chain-amino-acid-kit-mak003) - [Glycobiology - Carbohydrate Enzymes and Proteins](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/protein-biology/enzyme-activity-assays/carbohydrate-analysis) - [Coenzyme A](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/protein-biology/enzyme-activity-assays/coenzyme-a) - [LOPAC®1280 Small Molecules Screening](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/protein-biology/enzyme-activity-assays/compound-library-screening-lopac-1280-small-molecules) - [View More](https://www.sigmaaldrich.com/US/en/search/facet-search?focus=sitecontent&term=facet-search) __Related Product Categories__ - [Chiral Catalysts & Ligands](https://www.sigmaaldrich.com/US/en/products/chemistry-and-biochemicals/catalysts/chiral-catalysts-and-ligands) - [Lipids and Lipid Derivatives for Research](https://www.sigmaaldrich.com/US/en/products/chemistry-and-biochemicals/biochemicals/lipids) - [Environmental Accounting Supplier Toolkit](https://www.sigmaaldrich.com/US/en/life-science/ssbi/sustainability-toolkits/environmental-accounting-supplier-toolkit) - [Renewable Electricity Toolkit](https://www.sigmaaldrich.com/US/en/life-science/ssbi/sustainability-toolkits/renewable-electricity-toolkit) - [Crown Ethers and Cryptands for Advanced Applications](https://www.sigmaaldrich.com/US/en/technical-documents/product-supporting/crown-ethers-cryptands-advanced-applications) - [Purification of Extracellular Vesicles with Eshmuno® Q Resin and Natrix® Q Membrane](https://www.sigmaaldrich.com/US/en/technical-documents/product-supporting/membrane-chromatography/purification-extracellular-vesicles) - [Membrane Prefilters Improve Sterilizing Filter Capacity and Process Economics in Bioprocessing](https://www.sigmaaldrich.com/US/en/technical-documents/product-supporting/prefilters-bioburden-control/membrane-prefiltration-improves-sterilizing-filter-capacity-and-process-economics) - [Next Generation Virus Filtration Solutions](https://www.sigmaaldrich.com/US/en/technical-documents/product-supporting/virus-filters/next-generation-virus-filtration-solutions) - [View More](https://www.sigmaaldrich.com/US/en/search/facet-search?focus=sitecontent&term=facet-search) Top __Sign In To Continue__ To continue reading please sign in or create an account. 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