Metabolism of L-Carnitine Esters of ,&&ibstituted Palmitic Acid by Rat Liver Mitochondria*
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چکیده
The chemical synthesis and properties of L-carnitine esters of P-ketopalmitic acid, /3-hydroxypslmitic acid, and ~ranstr,P-unsaturated palmitic acid are described. Isolated rat liver mitochondria oxidize the carnitine esters of these acids more efficiently than the free acids as judged by acetoacetate production and oxygen uptake. Rat liver mitochondrial extracts catalyze the conversion of palmitoyl carnitine and fiketopalmitoyl carnitine to the CoA esters with equal efficiency. The rates of the reaction with the carnitine esters of /3-hydroxypalmitic acid and from-a, P-unsaturated palmitic acid were about 70% and 20% that obtained with palmitoyl-Lcarnitine. It is shown that /3-ketopalmitic acid is rapidly decarboxylated to yield pentadecanone by a nonspecific nonenzymatic reaction with several proteins.
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