Biomaterial Database

Comparison of the triacylglycerol hydrolase activity of human post-heparin plasma lipoprotein lipase and hepatic triacylglycerol lipase. A monolayer study. 1986

R L Jackson, and E Ponce, and L R McLean, and R A Demel

Interfacial catalysis of hepatic triacylglycerol lipase (H-TGL) and lipoprotein lipase (LpL) isolated from human post-heparin plasma was investigated with mixed monolayers of trioleoylglycerol (TO) and egg phosphatidylcholine. Rates of enzyme catalysis were dependent on surface pressure, substrate concentration, apoC-II (the activator protein for LpL), and cholesteryl oleate (CO). LpL showed a surface pressure optimum between 22 and 24 mN m-1, whereas H-TGL activity decreased at pressures greater than 20 mN m-1. LpL activity was enhanced greater than 10-fold by apoC-II; 1 M NaCl inhibited enzyme activity. ApoC-II, apoC-III, apoA-I, apoA-II, and 1 M NaCl had no effect on H-TGL activity. The substrate (TO) dependency was different for the two lipases. For LpL, there was a marked enhancement of enzyme activity between 2 and 4 mol % TO, whereas for H-TGL, enzyme activity increased linearly between 1 and 10 mol % TO. LpL activity toward monolayers containing 2 mol % TO was enhanced 2.6-fold by the addition of 5 mol % CO; cholesteryl ester had no effect on H-TGL activity. These findings suggest that the two lipolytic enzymes have different interfacial properties, which may have relevance to the rates of hydrolysis of triacylglycerols at a lipoprotein interface.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008049	Lipase	An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. It is produced by glands on the tongue and by the pancreas and initiates the digestion of dietary fats. (From Dorland, 27th ed) EC 3.1.1.3.	Triacylglycerol Lipase,Tributyrinase,Triglyceride Lipase,Acid Lipase,Acid Lipase A,Acid Lipase B,Acid Lipase I,Acid Lipase II,Exolipase,Monoester Lipase,Triacylglycerol Hydrolase,Triglyceridase,Triolean Hydrolase,Hydrolase, Triacylglycerol,Hydrolase, Triolean,Lipase A, Acid,Lipase B, Acid,Lipase I, Acid,Lipase II, Acid,Lipase, Acid,Lipase, Monoester,Lipase, Triglyceride
D008071	Lipoprotein Lipase	An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. The enzyme hydrolyzes triacylglycerols in chylomicrons, very-low-density lipoproteins, low-density lipoproteins, and diacylglycerols. It occurs on capillary endothelial surfaces, especially in mammary, muscle, and adipose tissue. Genetic deficiency of the enzyme causes familial hyperlipoproteinemia Type I. (Dorland, 27th ed) EC 3.1.1.34.	Heparin-Clearing Factor,Lipemia-Clearing Factor,Diacylglycerol Lipase,Diglyceride Lipase,Post-Heparin Lipase,Postheparin Lipase,Postheparin Lipoprotein Lipase,Factor, Heparin-Clearing,Factor, Lipemia-Clearing,Heparin Clearing Factor,Lipase, Diacylglycerol,Lipase, Diglyceride,Lipase, Lipoprotein,Lipase, Post-Heparin,Lipase, Postheparin,Lipase, Postheparin Lipoprotein,Lipemia Clearing Factor,Lipoprotein Lipase, Postheparin,Post Heparin Lipase
D008081	Liposomes	Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.	Niosomes,Transferosomes,Ultradeformable Liposomes,Liposomes, Ultra-deformable,Liposome,Liposome, Ultra-deformable,Liposome, Ultradeformable,Liposomes, Ultra deformable,Liposomes, Ultradeformable,Niosome,Transferosome,Ultra-deformable Liposome,Ultra-deformable Liposomes,Ultradeformable Liposome
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
D006493	Heparin	A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.	Heparinic Acid,alpha-Heparin,Heparin Sodium,Liquaemin,Sodium Heparin,Unfractionated Heparin,Heparin, Sodium,Heparin, Unfractionated,alpha Heparin
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006868	Hydrolysis	The process of cleaving a chemical compound by the addition of a molecule of water.
D013499	Surface Properties	Characteristics or attributes of the outer boundaries of objects, including molecules.	Properties, Surface,Property, Surface,Surface Property