title: Purification and properties of carnitine octanoyltransferase and carnitine palmitoyltransferase from rat liver.
abstract: The activities of carnitine octanoyltransferase (COT) and carnitine palmitoyltransferase (CPT) in rat liver were markedly increased by administration of di(2-ethyl-hexyl)phthalate. COT and CPT were purified from the enzyme-induced rat liver. COT was a 66,000-dalton polypeptide. The molecular weight of native CPT was 280,000--320,000 daltons, and the enzyme consisted of 69,200-dalton polypeptides. CAT, COT, and CPT were immunologically different. COT exhibited activity with all of the substrates tested (acyl-CoA's and acylcarnitines of saturated fatty acids having carbon chain lengths of C2--C20), though maximum activity was observed with hexanoyl derivatives. CPT exhibited catalytic activity with medium- and long-chain acyl derivatives. 2-Bromo-palmitoyl-CoA inactivated COT but not CPT. Malonyl-CoA inhibited CPT but not COT. CPT was confined to mitochondria, whereas COT was found in peroxisomes and the soluble compartment but not in mitochondria.
mesh_terms: D000217:Acyltransferases / Q000302:isolation & purification*; D000818:Animals; D000906:Antibodies / Q000302:isolation & purification; D002333:Carnitine Acyltransferases / Q000276:immunology / Q000302:isolation & purification*; D002334:Carnitine O-Palmitoyltransferase / Q000276:immunology / Q000302:isolation & purification*; D055598:Chemical Phenomena; D002621:Chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D008099:Liver / Q000201:enzymology*; D008297:Male; D008970:Molecular Weight; D051381:Rats; D011919:Rats, Inbred Strains; D013347:Subcellular Fractions / Q000201:enzymology; D013379:Substrate Specificity
chemical_list: D000906:Antibodies; D000217:Acyltransferases; D002333:Carnitine Acyltransferases; C030162:carnitine octanoyltransferase; D002334:Carnitine O-Palmitoyltransferase