Biomaterial Database

Phosphatidylcholine substrate specificity of lecithin: cholestrol acyltransferase-in high density lipoproteins and in lipids dispersions. 1977

S Yokoyama, and T Murase, and Y Akanuma

Lecithin: cholesterol acyltransferase (LCAT) was more highly activated by apolipoprotein A-I (apoA-I) with dimyristoyl phosphatidylcholine (DMPC) than with dilinoleoyl phosphatidylcholine (DLPC) when lipid dispersion of cholesterol and each phosphatidylcholine was used as a substrate. When the enzyme reactions were activated by whole apolipoproteins of high density lipoproteins (HDL), DLPC was more available to the LCAT reaction than DMPC with high concentrations of apoHDL in an incubation mixture. However, no detectable enzyme reaction was observed with dipalmitoyl phosphatidylcholine (DPPC) under both conditions. On the other hand, all of these phosphatidylcholines acted as substrates of LCAT when they were incorporated into HDL coupled to Sepharose. The order of their relative reactivities to cholesterol was DMPC, DPPC, AND DLPC under the conditions used.

UI	MeSH Term	Description	Entries
D007862	Phosphatidylcholine-Sterol O-Acyltransferase	An enzyme secreted from the liver into the plasma of many mammalian species. It catalyzes the esterification of the hydroxyl group of lipoprotein cholesterol by the transfer of a fatty acid from the C-2 position of lecithin. In familial lecithin:cholesterol acyltransferase deficiency disease, the absence of the enzyme results in an excess of unesterified cholesterol in plasma.	Lecithin Cholesterol Acyltransferase,Cholesterol Ester Lysolecithin Acyltransferase,Lecithin Acyltransferase,Phosophatidylcholine-Sterol Acyltransferase,Acyltransferase, Lecithin,Acyltransferase, Lecithin Cholesterol,Acyltransferase, Phosophatidylcholine-Sterol,Cholesterol Acyltransferase, Lecithin,O-Acyltransferase, Phosphatidylcholine-Sterol,Phosophatidylcholine Sterol Acyltransferase,Phosphatidylcholine Sterol O Acyltransferase
D008075	Lipoproteins, HDL	A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.	High Density Lipoprotein,High-Density Lipoprotein,High-Density Lipoproteins,alpha-Lipoprotein,alpha-Lipoproteins,Heavy Lipoproteins,alpha-1 Lipoprotein,Density Lipoprotein, High,HDL Lipoproteins,High Density Lipoproteins,Lipoprotein, High Density,Lipoprotein, High-Density,Lipoproteins, Heavy,Lipoproteins, High-Density,alpha Lipoprotein,alpha Lipoproteins
D005227	Fatty Acids	Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)	Aliphatic Acid,Esterified Fatty Acid,Fatty Acid,Fatty Acids, Esterified,Fatty Acids, Saturated,Saturated Fatty Acid,Aliphatic Acids,Acid, Aliphatic,Acid, Esterified Fatty,Acid, Saturated Fatty,Esterified Fatty Acids,Fatty Acid, Esterified,Fatty Acid, Saturated,Saturated Fatty Acids
D001053	Apolipoproteins	Protein components on the surface of LIPOPROTEINS. They form a layer surrounding the hydrophobic lipid core. There are several classes of apolipoproteins with each playing a different role in lipid transport and LIPID METABOLISM. These proteins are synthesized mainly in the LIVER and the INTESTINES.	Apolipoprotein
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In