title: Inhibition of rat heart ornithine decarboxylase by basic polypeptides.
abstract: Purified and partially purified ornithine decarboxylase (ODC) from rat heart was inhibited by basic polypeptides in vitro. Poly-L-arginine, the most effective, was inhibitory at a concentration as low as 0.1 microgram/ml; protamine and histone clearly inhibited ODC at concentrations higher than 2 micrograms/ml, but poly-L-lysine was less effective. The ability to inhibit ODC appeared to correlate with the arginine-residue content of basic polypeptides. The inhibition effect could be decreased by increasing substrate concentration and ionic strength.
mesh_terms: D000818:Animals; D006657:Histones / Q000494:pharmacology; D007700:Kinetics; D009206:Myocardium / Q000201:enzymology*; D009952:Ornithine / Q000378:metabolism; D065108:Ornithine Decarboxylase Inhibitors; D010455:Peptides / Q000494:pharmacology*; D011479:Protamines / Q000494:pharmacology; D051381:Rats
chemical_list: D006657:Histones; D065108:Ornithine Decarboxylase Inhibitors; D010455:Peptides; D011479:Protamines; C015462:polyarginine; D009952:Ornithine