Activation of the phospholipase A1 activity of lipoprotein lipase by apoprotein C-II.
The effect of apo very low density lipoprotein (apo VLDL) and apoprotein C-II on the phospholipase A1 activity associated with lipoprotein lipase (E.C.3.1.1.3) was studied using purified bovine milk lipoprotein lipase. The enzyme degraded 14C phosphatidylcholine (PC) to 14C 2-acyl lysophosphatidylcholine at a rate of 0.28 +/- 0.01 nmol/min/ml and triolein at a rate of 20.3 +/- 0.4 nmol/min/ml in mixed emulsions of PC and triolein. The phospholipase activity and triacylglycerol lipase activity were both increased by the addition of apo VLDL and apoprotein C-II. After maximal activation, the rate of PC degradation was 1.19 +/- 0.02 nmol/min/ml and triolein degradation 64.4 +/- 0.4 nmol/min/ml. Activation of phospholipase A1 activity and triacylglycerol lipase activity occurred in parallel.
D000818:Animals; D053304:Apolipoprotein C-II; D001053:Apolipoproteins / Q000097:blood / Q000494:pharmacology*; D001056:Apolipoproteins C; D002417:Cattle; D004789:Enzyme Activation; D005260:Female; D006801:Humans; D006954:Hyperlipoproteinemia Type V / Q000097:blood; D007700:Kinetics; D008071:Lipoprotein Lipase / Q000378:metabolism*; D008079:Lipoproteins, VLDL / Q000097:blood / Q000494:pharmacology*; D008892:Milk / Q000201:enzymology; D010740:Phospholipases / Q000378:metabolism*; D010741:Phospholipases A / Q000378:metabolism*; D054466:Phospholipases A1
D053304:Apolipoprotein C-II; D001053:Apolipoproteins; D001056:Apolipoproteins C; D008079:Lipoproteins, VLDL; D010740:Phospholipases; D010741:Phospholipases A; D054466:Phospholipases A1; D008071:Lipoprotein Lipase