Hydrolysis of cholesteryl oleate liquid crystals by hormone-sensitive lipase. 1993

T Tsujita, and H Okuda
Department of Medical Biochemistry, School of Medicine, Ehime University.

Cholesteryl oleate liquid crystals were prepared by sonication as a model of lipid droplets accumulated in foam cells derived from macrophages. These liquid crystals were spherical and showed an anisotropic cross image. Hormone-sensitive lipase from bovine adipose tissue hydrolyzed these liquid crystals optimally at pH 6.8. The Km for the liquid crystals was about 8 times that for vesicles or emulsified cholesteryl oleate. The Vmax for the liquid crystals was the same as that for the emulsified substrate and 6 times that for the vesicle substrate. Phospholipid inhibited cholesteryl oleate hydrolysis in a concentration-dependent fashion, phosphatidylserine being especially inhibitory. The effect of phospholipids on the activity changed upon their incorporation into the cholesteryl oleate liquid crystals, phosphatidylethanolamine increasing the activity to about twice that of the control. These results suggest that hormone-sensitive lipase hydrolyzes cholesteryl oleate liquid crystals as a model of endogenous lipid droplets and its activities are affected by phospholipids.

UI MeSH Term Description Entries
D007700 Kinetics The rate dynamics in chemical or physical systems.
D008855 Microscopy, Electron, Scanning Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY. Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D010743 Phospholipids Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system. Phosphatides,Phospholipid
D002417 Cattle Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor. Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D002787 Sterol Esterase An enzyme that catalyzes the hydrolysis of CHOLESTEROL ESTERS and some other sterol esters, to liberate cholesterol plus a fatty acid anion. Cholesterol Esterase,15-Ketosteryl Oleate Hydrolase,Acylcholesterol Lipase,Cholesterol Ester Hydrolase,Cholesteryl Oleate Hydrolase,Cholesterylester Hydrolase,Hormone-Sensitive Lipase,Lipase A (Lysosomal Acid Cholesterol Esterase),Lipoidal Steroid Esterase,Lysosomal Acid Cholesterol Esterase,Lysosomal Acid Lipase,Steroid Hormone Esterase,Sterol Ester Acylhydrolase,15 Ketosteryl Oleate Hydrolase,Acid Lipase, Lysosomal,Acylhydrolase, Sterol Ester,Esterase, Cholesterol,Esterase, Lipoidal Steroid,Esterase, Steroid Hormone,Esterase, Sterol,Hormone Sensitive Lipase,Hydrolase, 15-Ketosteryl Oleate,Hydrolase, Cholesterol Ester,Hydrolase, Cholesteryl Oleate,Hydrolase, Cholesterylester,Lipase, Acylcholesterol,Lipase, Hormone-Sensitive,Steroid Esterase, Lipoidal
D002788 Cholesterol Esters Fatty acid esters of cholesterol which constitute about two-thirds of the cholesterol in the plasma. The accumulation of cholesterol esters in the arterial intima is a characteristic feature of atherosclerosis. Cholesterol Ester,Cholesteryl Ester,Cholesteryl Esters,Ester, Cholesterol,Ester, Cholesteryl,Esters, Cholesterol,Esters, Cholesteryl
D003460 Crystallization The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed) Crystalline Polymorphs,Polymorphism, Crystallization,Crystal Growth,Polymorphic Crystals,Crystal, Polymorphic,Crystalline Polymorph,Crystallization Polymorphism,Crystallization Polymorphisms,Crystals, Polymorphic,Growth, Crystal,Polymorph, Crystalline,Polymorphic Crystal,Polymorphisms, Crystallization,Polymorphs, Crystalline
D006868 Hydrolysis The process of cleaving a chemical compound by the addition of a molecule of water.
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia

Related Publications

T Tsujita, and H Okuda
August 2008, Journal of lipid research,
T Tsujita, and H Okuda
April 2002, Biochemical and biophysical research communications,
T Tsujita, and H Okuda
June 1998, Arteriosclerosis, thrombosis, and vascular biology,
T Tsujita, and H Okuda
January 1999, Methods in molecular biology (Clifton, N.J.),
Copied contents to your clipboard!