Purification and properties of carnitine octanoyltransferase and carnitine palmitoyltransferase from rat liver

J Biochem. 1983 Aug;94(2):529-42. doi: 10.1093/oxfordjournals.jbchem.a134384.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyltransferases / isolation & purification*
  • Animals
  • Antibodies / isolation & purification
  • Carnitine Acyltransferases / immunology
  • Carnitine Acyltransferases / isolation & purification*
  • Carnitine O-Palmitoyltransferase / immunology
  • Carnitine O-Palmitoyltransferase / isolation & purification*
  • Chemical Phenomena
  • Chemistry
  • Electrophoresis, Polyacrylamide Gel
  • Liver / enzymology*
  • Male
  • Molecular Weight
  • Rats
  • Rats, Inbred Strains
  • Subcellular Fractions / enzymology
  • Substrate Specificity


  • Antibodies
  • Acyltransferases
  • Carnitine Acyltransferases
  • carnitine octanoyltransferase
  • Carnitine O-Palmitoyltransferase