The localization of acyl coenzyme A-carnitine acyltransferases in rat liver cells.

نویسندگان

  • K R Norum
  • J Bremer
چکیده

The distribution of acetyl coenzyme A-carnitine acetyltransferase (EC 2.3.1.7) and of palmityl-CoA-carnitine palmityltransferase (EC 2.3.1) in subcellular fractions of rat liver has been studied. The distribution of carnitine pahnityltransferase in the different fractions obtained with differential centrifugation and with centrifugation in a steep sucrose gradient correlated closely with the distribution of the mitochondrial marker enzymes, glutamate dehydrogenase (EC 1.4.1.3) and D-phydroxybutyrate dehydrogenase (EC 1.1.1.30). Carnitine acetyltransferase also most probably is a mitochondrial enzyme. The results obtained suggest that this enzyme is present in a mitochondrial population not identical with the population rich in carnitine palmityltransferase and in the mitochondrial marker enzymes used. Most of the carnitine acyltransferases were found in the membranous part of the mitochondria. The findings presented are consistent with the hypothesis that the carnitine acyltransferases are present in the membranous part of the mitochondria which is the barrier for the acyl-CoA molecules.

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عنوان ژورنال:
  • The Journal of biological chemistry

دوره 242 3  شماره 

صفحات  -

تاریخ انتشار 1967