Coenzyme A

Coenzyme A, referred to in the literature as HSCoA or just CoA, belongs to the group-transferring enzymes.

Its ability to transfer groups is used by ``synthetases'', which generate activated acyls, i.e. acyl&minus;CoA, the best known of which is acetyl&minus;CoA during the hydrolytic splitting of ATP with the help of coenzyme A ]. These acyl&minus;CoAs contain a thioester bond in which the remainder of the carboxyl group is attached to the -SH group of coenzyme A. The important thing about acyl&minus;CoAs is that many important reactions take place on their β&minus;carbon (i.e. C2 acyl) thanks to the activation of hydrogens. The best known are dehydration' in β-oxidation of fatty acids or condensation in the reaction of acetyl&minus;CoA with oxaloacetate in the Krebs cycle.

Structure of Coenzyme A molecule
The vitamin precursor for coenzyme A is pantothenic acid (vitamin B5), consisting of pantoic acid and β-alanine. Other structural components of coenzyme A are the biogenic amine cysteamine and adenosine-3'-phosphate-5'-diphosphate.

[[File:Coenzyme A beschriftet.svg|thumb|500px|center|1: adenosine-3'-phosphate

2: diphosphate

3: pantoic acid

4: β-Alanine

5: cysteamine

1+2: adenosine-3'-monophosphate-5'-diphosphate

3+4: pantothenic acid

3+4+5: pantetheine]]

Related Articles

 * Coenzymes
 * Enzymes
 * Macroergic compounds
 * Basic biogenic amines