A macromolecular inhibitor of the antizyme to ornithine decarboxylase.
A macromolecular factor that inhibits the activity of the antizyme to ornithine decarboxylase (ODC) was found in rat liver extracts. The factor, 'antizyme inhibitor', was heat-labile, non diffusable and of similar molecular size to ODC. The antizyme inhibitor re-activated ODC that had been inactivated by antizyme, apparently by replacing ODC in a complex with antizyme. Therefore the antizyme inhibitor can be used to assay the amount of inactive ODC-antizyme complex formed in vitro. When assayed by this method, the complex was shown to be eluted before ODC from a Sephadex G-100 column. Significant increase in ODC activity was observed when the antizyme inhibitor was added to crude liver extracts from rats that had been injected with 1,3-diaminopropane to cause decay of ODC activity, suggesting the presence of inactive ODC-antizyme complex in the extracts.
D000818:Animals; D002262:Carboxy-Lyases / Q000037:antagonists & inhibitors*; D002850:Chromatography, Gel; D004789:Enzyme Activation / Q000187:drug effects; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008297:Male; D065108:Ornithine Decarboxylase Inhibitors; D011506:Proteins / Q000037:antagonists & inhibitors*; D051381:Rats; D011919:Rats, Inbred Strains
D065108:Ornithine Decarboxylase Inhibitors; D011506:Proteins; C031017:ornithine decarboxylase antizyme; D002262:Carboxy-Lyases