coenzyme A

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coenzyme A

biochemistry

Also known as: CoA

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June 24, 2026

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Coenzyme A (CoA) is a vital coenzyme found in all living cells, playing a crucial role in the metabolism of carbohydrates, fats, and certain amino acids. It is essential for breaking down these molecules to release energy.12

CoA's structure includes a sulfhydryl group (-SH) that is key to its function in transferring acyl groups. This molecule is involved in numerous metabolic pathways, including the breakdown of fatty acids, where it forms fatty acyl coenzyme A molecules. These molecules are then further processed in the tricarboxylic acid (TCA) cycle, a central pathway for energy production. CoA also plays a role in the synthesis of cellular components, helping to replenish intermediates in metabolic cycles.3245

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carboxylic acid
Saturated aliphatic acids
…a large biochemical molecule called coenzyme A; the entire compound is known as acetyl coenzyme A. In the metabolism of food materials (the body’s conversion of food to energy), the carbon atoms of carbohydrates, fats, and, to some degree, proteins are converted to acetyl groups that are bonded to coenzyme…
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…a large biochemical molecule called coenzyme A; the entire compound is known as acetyl coenzyme A. In the metabolism of food materials (the body’s conversion of food to energy), the carbon atoms of carbohydrates, fats, and, to some degree, proteins are converted to acetyl groups that are bonded to coenzyme…
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Fritz Albert Lipmann
…Medicine for the discovery of coenzyme A, an important catalytic substance involved in the cellular conversion of food into energy.
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…Medicine for the discovery of coenzyme A, an important catalytic substance involved in the cellular conversion of food into energy.
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vitamin
Functions
…protein metabolism; this coenzyme (coenzyme A) acts at the hub of these reactions and thus is an important molecule in controlling the interconversion of fats, proteins, and carbohydrates and their conversion into metabolic energy. Thiamin and vitamin B₆ coenzymes control the conversion of carbohydrates and proteins respectively into metabolic…
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…protein metabolism; this coenzyme (coenzyme A) acts at the hub of these reactions and thus is an important molecule in controlling the interconversion of fats, proteins, and carbohydrates and their conversion into metabolic energy. Thiamin and vitamin B₆ coenzymes control the conversion of carbohydrates and proteins respectively into metabolic…
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lipid
Oxidation of fatty acids
…thioester of a molecule called coenzyme A, or CoA. (A thioester is a compound in which the linking oxygen in an ester is replaced by a sulfur atom.) Oxidation of the fatty acid–CoA thioesters actually takes place in discrete vesicular bodies called mitochondria. Most cells contain many mitochondria, each roughly…
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…thioester of a molecule called coenzyme A, or CoA. (A thioester is a compound in which the linking oxygen in an ester is replaced by a sulfur atom.) Oxidation of the fatty acid–CoA thioesters actually takes place in discrete vesicular bodies called mitochondria. Most cells contain many mitochondria, each roughly…
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metabolism
Formation of fatty acyl coenzyme A molecules
, CH₃C∣=O)—namely, coenzyme A. The functional portion of this complex molecule is the sulfhydryl (―SH) group at one end. The coenzyme is often identified as CoA―SH (step [21]). The organized and stepwise degradation of fatty acids linked to coenzyme A is ensured because the necessary enzymes are…
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, CH₃C∣=O)—namely, coenzyme A. The functional portion of this complex molecule is the sulfhydryl (―SH) group at one end. The coenzyme is often identified as CoA―SH (step [21]). The organized and stepwise degradation of fatty acids linked to coenzyme A is ensured because the necessary enzymes are…
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