Long-chain carnitine acyltransferase and the role of acylcarnitine derivatives in the catalytic increase
نویسندگان
چکیده
Carnitine-H3 or palmitate-U4 incubated with heart muscle preparations waa incorporated into a compound that had chromatographic behavior in several systems identical to that of palmitylcarnitine chemically synthesized from palmityl chloride and carnitine. Palmitylcarnitine biosynthesis from palmitic acid and carnitine was dependent upon ATP and CoA in addition to substrates and an enzyme preparation. In contrast, palmityl carnitine formation from palmityl CoA and carnitine did not require ATP or CoA. The following reaction, catalyzed by palmitylcarnitine transferase, was shown to be reversible: Palmitylcarnitine + Cod S palmityl CoA + carnitine.
منابع مشابه
Long-chain Carnitine Acyltransferase and the Role of Acylcarnitine Derivatives in the Catalytic Increase of Fatty Acid Oxidation Induced by Carnitine.
Carnitine-H3 or palmitate-U4 incubated with heart muscle preparations waa incorporated into a compound that had chromatographic behavior in several systems identical to that of palmitylcarnitine chemically synthesized from palmityl chloride and carnitine. Palmitylcarnitine biosynthesis from palmitic acid and carnitine was dependent upon ATP and CoA in addition to substrates and an enzyme prepar...
متن کاملChanges in the subcellular distribution of free carnitine and its acyl derivatives in diabetic rat hearts following treatment with L-carnitine.
Carnitine deficiency has been demonstrated in diabetic hearts, and it is also well known that L-carnitine administration has a beneficial effect on cardiac function. Carnitine treatment would be expected to reduce the accumulation of long-chain acylcarnitine. However, many reports have shown that myocardial long-chain acylcarnitine levels were increased following treatment with L-carnitine in w...
متن کاملThe substrate specificity of carnitine acetyltransferase.
1. A study of the acyl group specificity of the carnitine acetyltransferase reaction [acyl-(-)carnitine+CoASH right harpoon over left harpoon (-)-carnitine+acyl-CoA] has been made with the enzyme from pigeon breast muscle. Acyl groups containing up to 10 carbon atoms are transferred and detailed kinetic investigations with a range of acyl-CoA and acylcarnitine substrates are reported. 2. Acyl-C...
متن کاملEffect of L-carnitine on the cellular distribution of carnitine and its acyl derivatives in the ischemic heart.
The purpose of this study was to investigate the cellular distribution of carnitine and its acyl derivatives in the normal and ischemic myocardium, and the effects of exogenous 1-carnitine on this distribution and mitochondrial function in the ischemic dog heart. Under non-ischemic conditions, about 93% of the total cellular carnitine was located in the cytosolic compartment and 6.5% in the mit...
متن کاملIn support of the roles of malonyl-CoA and carnitine acyltransferase I in the regulation of hepatic fatty acid oxidation and ketogenesis.
The rate of fatty acid synthesis in hepatocytes from meal-fed rats was manipulated over a wide range using glucose, lactate, and pyruvate to drive the system maximally, and glucagon, 5-(tetradecyloxy)-2-furoic acid (RMI 14,514), or a combination of both agents to inhibit lipogenesis. Measurements were made of cellular malonyl-CoA levels, long chain acylcarnitine concentration, and [l-‘4C]oleate...
متن کامل