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Metabolic functions of pantothenic acid
Domina Petric, MD
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General functions Both CoA and ACP/4'-phosphopantetheine function metabolically as carriers of acyl groups and activators of carbonyl groups in a large number of vital metabolic transformations. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Coenzyme A Coenzyme A serves as an essential cofactor for some 4% of known enzymes, including at least 100 in intermediary metabolism. In these reactions CoA forms high-energy thioester bonds with carboxylic acids, the most important of which is acetic acid. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Coenzyme A As acetyl CoA, the so-called active acetate group can enter the TCA cycle and be used for the synthesis of fatty acids or isopranoid compounds (cholesterol, steroid hormones). November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Coenzyme A Acetyl CoA is used in acetylations of alcohols, amines and amino acids (choline, sulfonamides, p-aminobenzoate, proteins). November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Acetyl CoA is used in the oxidation of amino acids.
Coenzyme A Acetyl CoA is used in the oxidation of amino acids. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Coenzyme A Acetyl CoA participates in the N-terminal acetylation in more than half of eukaryotic proteins. This includes the processing of certain peptide hormones from their polyprotein precursors: processing of ACTH to α-melanocyte-stimulating hormone processing of ß-lipotropin to ß-endorphin tissue-dependent acetylation of those products November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Coenzyme A Acetyl CoA participates in the internal acetylation of proteins, including histones and α-tubulin internal lysinyl, residues of which are reversibly acetylated. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Coenzyme A Acyl CoAs are used to modify a large number of proteins: GTP-binding proteins, protein kinases, membrane receptors, cytoskeletal proteins, mitochrondial proteins, through the addition of long-chain fatty acids. These reactions most frequently involve palmitic acid, which is added post-translationally in a reversible ester bond, and myristic acid, which is added co-translationally in an irreversible amide linkage. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Coenzyme A Acyl CoAs are used to activate fatty acids for incorporation into triglycerides, membrane phospholipids and regulatory sphingolipids. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Coenzyme A Acyl CoAs are transacylated to carnitine to form energy-equivalent acylcarnitines capable of being transported into the mitochondria where ß-oxidation occurs. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Coenzyme A Acyl CoAs are involved in the production of acetoacetate, a ketone body derived from fat metabolism when glucose is limiting. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Acyl-Carrier Protein (ACP)
The acyl-carrier protein is a component of the multienzyme complex fatty acid synthase. In ACP, the cofactor functions to transfer covalently bound intermediates between different active sites with successive cycles of condensations and reductions. 4'-phosphopantetheine is the prosthetic group for the binding and transfer of the acyl units during this metabolism. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Acyl-Carrier Protein (ACP)
The sulfhydryl group of the cofactor serves as the point of temporary covalent attachment of the growing fatty acid via a thiol linkage each time a malonic acid moiety is added by transfer to the cofactor. The cofactor appears to function as a swinging arm, allowing the growing fatty acid to reach the various catalytic sites of the enzyme. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Health effects November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Reduced serum cholesterol levels
High doses ( mg/day) of pantothine, the dimmer of pantetheine, has been shown to reduce serum total and low-density lipoprotein-associated cholesterol and triglycerides, and to increase high-density lipoprotein-associated cholesterol. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Rheumatoid arthritis A randomized control trial showed that high doses (up to 2 g/day) of calcium pantothenate reduced the duration of morning stiffness, the degree of disability and the severity of pain for rheumatoid arthritis patients. November 21, 2018 Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
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Literature Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc November 21, 2018
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