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pantothenic acid

Wednesday 30 July 2008

Pantothenic acid, also called vitamin B5 (a B vitamin), is a water-soluble vitamin required to sustain life (essential nutrient).

Pantothenic acid is needed to form coenzyme-A (CoA), and is critical in the metabolism and synthesis of carbohydrates, proteins, and fats.

In chemical structure, it is the amide between D-pantoate and beta-alanine.

Its name is derived from the Greek pantothen (παντόθεν) 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.

Structure

Only the dextrorotatory (D) isomer of pantothenic acid possesses biologic activity. The levorotatory (L) form may antagonize the effects of the dextrorotatory isomer.

Functiond

Pantothenic acid is used in the synthesis of coenzyme A (CoA). Coenzyme A may act as an acyl group carrier to form acetyl-CoA and other related compounds; this is a way to transport carbon atoms within the cell.

The transfer of carbon atoms by coenzyme A is important in cellular respiration, as well as the biosynthesis of many important compounds such as fatty acids, cholesterol, and acetylcholine.

Acetyl-CoA is used in the condensation of oxaloacetate to citrate at the initiation of the citric acid cycle (TCA cycle or Krebs cycle). From the citric acid cycle, acetyl-CoA can also initiate the fatty acid synthesis pathway.

Since pantothenic acid participates in a wide array of key biological roles, it is considered essential to all forms of life. As such, deficiencies in pantothenic acid may have numerous wide-ranging effects.

Pantothenic acid is vital for a healthy pregnancy.

See also

- coenzyme A (CoA)
- acetyl-CoA