Article: Pantothenic acid

Pantothenic acid
General
Systematic name	3-[(2,4-dihydroxy-3,3-dimethyl- butanoyl)amino]propanoic acid
CAS number	Calcium Pantothenate (CAS: 137-08-6)
Molecular formula	C9H17NO5
SMILES	CC(C)(CO)C(C(=O)NCCC(=O)O)O
Molar mass	219.235 g/mol
Infobox disclaimer and references

Pantothenic acid, also called vitamin B₅, is a water-soluble vitamin required to sustain life. Pantothenic acid is needed to form coenzyme-A (CoA), and is thus critical in the metabolism and synthesis of carbohydrates, proteins, and fats. Its name is derived from the Greek pantothen meaning "from everywhere" and small quantities of pantothenic acid are found in nearly every food, with high amounts in whole grain cereals, legumes, eggs, meat, and royal jelly. It is commonly found as its alcohol analog, the provitamin panthenol, and as calcium pantothenate. The dimeric form Pantethine is considered to be the more active form of the vitamin in the body, but is unstable at high temperatures or when stored for long periods, so calcium pantothenate is the more usual form of vitamin B5 when it is sold as a dietary supplement.

Biologic Role

Pantothenic acid is a precursor to cortisone and is required to sustain life since it is a component of coenzyme-A.

Coenzyme A is synthesised in a five step process from pantothenate; first phosphorylated to 4'-phosphopantothenate by the enzyme pantothenate kinase, next a cysteine is added to form (R)-4'-phospho-N-pantothenoylcysteine (PPC), which then is decarboxylated to 4'-phosphopantetheine.

4'-phosphopantetheine is finally converted to Coenzyme A by the enzymes 4'-phosphopantetheine adenylyltransferase and dephospho-CoA kinase.

This makes pantothenic acid necessary in the synthesis of fats, steroids and steroid derivatives (such as cholesterols), proteins, and the neurotransmitter acetylcholine.