Activation of lipoprotein lipase by native and acylated peptides of apolipoprotein C-II.
Apolipoprotein C-II, a protein found associated with all major classes of plasma lipoproteins, is a potent activator of the enzyme lipoprotein lipase. We have prepared the maleyl, citraconyl and succinyl derivatives of apolipoprotein C-II, and compared the capacities of the intact and tryptically cleaved proteins to activate lipoprotein lipase. The NH2-terminal 50 residue peptide proved virtually inactive, even after removal of the masking groups from the citraconyl derivative. The COOH-terminal 29 residue peptides of maleyl and citraconyl apolipoprotein C-II were more active than the corresponding succinylated peptide. After deacylation of the citraconyl derivative, the COOH-terminal peptide had maximal activity as great as apolipoprotein C-II, although the profile of activation remained dissimilar at low activator concentrations.
D000215:Acylation; D001053:Apolipoproteins / Q000494:pharmacology*; D055598:Chemical Phenomena; D002621:Chemistry; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D008071:Lipoprotein Lipase / Q000378:metabolism*; D010446:Peptide Fragments / Q000494:pharmacology; D010455:Peptides / Q000494:pharmacology*; D014357:Trypsin
D001053:Apolipoproteins; D010446:Peptide Fragments; D010455:Peptides; D008071:Lipoprotein Lipase; D014357:Trypsin