Coenzyme A

Description

Coenzyme A (CoA) is an essential cofactor functioning as an acyl group carrier and carbonyl-activating group for the citric acid cycle and fatty acid metabolism. About 4% of cellular enzymes utilize CoA as a substrate. It is synthesized from pantothenic acid in a 5-step process that requires ATP. The pantothenate kinase step of the CoA biosynthetic pathway has been identified as a target for the development of antibacterial compounds.

Description

Coenzyme A is a cofactor in enzymatic acyl transfer reactions. It participates in the biosynthesis and oxidation of fatty acids and the oxidation of pyruvate in the citric acid cycle. It was discovered by Nobel laureate Fritz Lipmann in 1945. A conjugate of coenzyme A with RNA was?recently reported?by David R. Liu and co-workers at Harvard.

Chemical properties

yellowish lyophilisate

The Uses of Coenzyme A

A hydrated form of Coenzyme A (CoA) is a useful biochemical research chemical, used in the preparation of high-yielding cell-free protein synthesis platforms.

The Uses of Coenzyme A

Coenzyme A hydrate has been used in the thiolase enzyme assay of recombinant acetoacetyl-CoA thiolase (rACAT) in Clonorchis sinensis. It may be used as a reference standard in Raman spectra measurements.

Definition

ChEBI: Coenzyme A is a thiol comprising a panthothenate unit in phosphoric anhydride linkage with a 3',5'-adenosine diphosphate unit; and an aminoethanethiol unit. It has a role as an Escherichia coli metabolite, a mouse metabolite and a coenzyme. It is functionally related to an ADP. It is a conjugate acid of a coenzyme A(4-).

General Description

Coenzyme A (CoA) is a cofactor with a molecular weight of 797 Da. Its biological structure is formed from pantothenic acid (vitamin B5), cysteine and adenosine triphosphate through an evolutionarily conserved pathway. CoA is primarily involved in cellular oxidative pathways, including fatty acid beta-oxidation, carbohydrate, amino acid oxidation, and the Krebs cycle; as well as in lipid synthesis, protein modification, and membrane transport. CoA serves as a carrier for the activation of acyl groups, which can be transferred to amides, esters, or acid anhydrides. CoA can also be regulate a variety of metabolic processes at different levels as substrates, allosteric regulators, and through post-translational modifications of histones and other non-histone proteins. It is an essential cofactor in all organisms.

Biochem/physiol Actions

Coenzyme A is a cofactor involved in acyl group transfer. It is essential for carbohydrate, lipid and protein metabolism. Coenzyme A acts as a cofactor for vitamin B coenzymes.

Purification Methods

The white powder is best stored in an inert atmosphere in the dark in sealed ampoules after drying in vacuo over P2O5 at 34o. It has UV: max 259 nm ( 16,800) in H2O. [Buyske et al. J Am Chem Soc 76 3575 1954.] It is soluble in H2O but insoluble in EtOH, Et2O and M2CO. It is readily oxidised in air and is best kept as the more stable trilithium salt [Moffat & Khorana J Am Chem Soc 83 663 1961; see also Beinert et al. J Biol Chem 200 384 1953, De Vries et al. J Am Chem Soc 72 4838 1950, Gregory et al. J Am Chem Soc 74 854 1952 and Baddiley Adv Enzymol 16 1 1955]. [Beilstein 26 III/IV 3663.]