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PubMed · 2981478

Coenzyme A metabolism.

J D Robishaw·J R Neely
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Abstract

The metabolism of coenzyme A and control of its synthesis are reviewed. Pantothenate kinase is an important rate-controlling enzyme in the synthetic pathway of all tissues studied and appears to catalyze the flux-generating reaction of the pathway in cardiac muscle. This enzyme is strongly inhibited by coenzyme A and all of its acyl esters. The cytosolic concentrations of coenzyme A and acetyl coenzyme A in both liver and heart are high enough to totally inhibit pantothenate kinase under all conditions. Free carnitine, but not acetyl carnitine, deinhibits the coenzyme A-inhibited enzyme. Carnitine alone does not increase enzyme activity. Thus changes in the acetyl carnitine-to-carnitine ratio that occur with nutritional states provides a mechanism for regulation of coenzyme A synthetic rates. Changes in the rate of coenzyme A synthesis in liver and heart occurs with fasting, refeeding, and diabetes and in heart muscle with hypertrophy. The pathway and regulation of coenzyme A degradation are not understood.

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Acetyl Coenzyme AAnimalsCoenzyme ADietKineticsLiverMyocardiumPantothenic AcidPhosphotransferasesPhosphotransferases (Alcohol Group Acceptor)Subcellular FractionsTissue DistributionJournal ArticleReview

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J D Robishaw, J R Neely. 1985. Coenzyme A metabolism.. https://doi.org/10.1152/ajpendo.1985.248.1.e1

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