title: Activation of lipoprotein lipase by N-alpha-palmitoyl (56-79) fragment of apolipoprotein C-II.
abstract: The effect of apolipoprotein C-II (apoC-II) and a synthetic fragment of apoC-II corresponding to residues 56-79 on the lipoprotein lipase (LpL) catalyzed hydrolysis of trioleoylglycerol in a monolayer of egg phosphatidylcholine and of dipalmitoylphosphatidylcholine vesicles was examined. Synthetic peptide 56-79, which does not associate with lipid, did not activate LpL at surface pressures greater than 30 mN/m; apoC-II is active up to 34 mN/m. However, acylation of the NH2-terminus of peptide 56-79 with palmitoyl chloride gave nearly identical LpL activating properties as compared to apoC-II. We conclude that at high surface pressures the lipid-binding region of apoC-II (residues 44-55) plays an essential role in LpL activation.
mesh_terms: D053304:Apolipoprotein C-II; D001056:Apolipoproteins C / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D050356:Lipid Metabolism; D008071:Lipoprotein Lipase / Q000378:metabolism*; D010168:Palmitates / Q000378:metabolism; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D053304:Apolipoprotein C-II; D001056:Apolipoproteins C; D010168:Palmitates; D010446:Peptide Fragments; D008071:Lipoprotein Lipase