Effect of phospholipids on the hydrolysis of cholesterol oleate liquid crystals by lysosomal acid lipase.
Cholesterol oleate liquid crystals were prepared in vitro as a model of lipid droplets accumulated in the atheromatous aorta. The hydrolysis of cholesterol oleate crystals by lysosomal acid lipase was examined in the presence and absence of various phospholipids. Phosphatidylserine markedly stimulated the hydrolysis of cholesterol oleate liquid crystals (20 times the basal value); it increased the Vmax value about 15 times and decreased the Km value to 1/20 times the basal value. The polar head group and the acyl chains of phosphatidylserine were required for its stimulation of hydrolysis.
D000818:Animals; D002788:Cholesterol Esters / Q000378:metabolism*; D003460:Crystallization; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008049:Lipase / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008247:Lysosomes / Q000201:enzymology; D010743:Phospholipids / Q000378:metabolism; D011817:Rabbits
D002788:Cholesterol Esters; D010743:Phospholipids; C014409:cholesteryl oleate; D008049:Lipase