pantothenate

Pantothenate, the anionic form of pantothenic acid, is a water-soluble B vitamin (vitamin B5) that functions as a key precursor in the synthesis of coenzyme A (CoA) and the phosphopantetheine moiety used by acyl carrier proteins. It is widely distributed in foods and is required for normal metabolism.

Dietary sources include meat, fish, poultry, eggs, dairy products, legumes, whole grains, seeds, and many vegetables. Humans absorb pantothenate from the small intestine and transport it in the bloodstream, with excess excreted in urine. Pantothenate is readily available from a typical diet and is often included in multivitamin and B-complex preparations.

Role in metabolism and biosynthesis. Pantothenate is converted in cells to 4′-phosphopantothenate and then ultimately to CoA, a central cofactor in energy metabolism. CoA participates in the formation and oxidation of fatty acids, the metabolism of carbohydrates through acetyl-CoA feeding into the TCA cycle, and various other acyl-transfer reactions essential for energy production and biosynthesis. In bacteria and plants, pantothenate-derived CoA also contributes to the synthesis of essential biomolecules via acyl carrier proteins.

Deficiency and safety. Pantothenate deficiency is rare in humans because of its ubiquity in foods; when it occurs, symptoms may include fatigue, irritability, numbness or paresthesias, and nausea. No widely established upper intake limit is set for pantothenate, and high-dose supplements are generally well tolerated, though gastrointestinal upset can occur in some individuals.

In summary, pantothenate is a essential micronutrient for CoA biosynthesis and energy metabolism, with diverse dietary sources and a high safety profile under typical intake.