The effect of fasting on the activity of liver carnitine palmitoyltransferase and its inhibition by malonyl-CoA.
The effect of fasting on palmitoyl-CoA: carnitine palmitoyltransferase (EC 2.3.1.21) in rat liver mitochondria and its inhibition by malonyl-CoA has been investigated. The activity of the outer carnitine palmitoyltransferase (transferase I) is nearly doubled after 24 h fasting, while the activity of total carnitine palmitoyltransferase (transferase I + II) increases only about 25%. The inhibition of the increased outer transferase by malonyl-CoA is decreased in fasting rats. The results suggest that carnitine palmitoyltransferase less sensitive to malonyl-CoA is exposed on the outer surface of the inner mitochondrial membrane in fasting, thus reducing the latency of the enzyme.
D000214:Acyl Coenzyme A / Q000494:pharmacology*; D000217:Acyltransferases / Q000378:metabolism*; D000818:Animals; D002334:Carnitine O-Palmitoyltransferase / Q000378:metabolism*; D005215:Fasting; D007700:Kinetics; D008316:Malonyl Coenzyme A / Q000494:pharmacology*; D008930:Mitochondria, Liver / Q000201:enzymology*; D051381:Rats
D000214:Acyl Coenzyme A; D008316:Malonyl Coenzyme A; D000217:Acyltransferases; D002334:Carnitine O-Palmitoyltransferase