Pantothenic acid is found in many diverse types of living materials. Chemically, it consists of ß-alanine in a peptid linkage with a dihydroxy acid. (ß-alanine differs from ordinary alanine in being ß-aminopropionic acid instead of α-aminopropionic acid.) The formula of pantothenic acid is given below:
The acid is unstable and for this reason is sold as a calcium salt. This salt is a white powder, readily soluble in water but not in alcohol.
Many organisms from bacteria and protozoa to higher mammals require pantothenic acid. In its absence these organisms do not grow properly and they may show various ill effects. Symptoms of pantothenic acid deficiency include dermatitis (inflammation of the skin) in rats, deficient feathering in chicks, graying of hair in rats, degeneration of the nervous system in pigs, hemorrhages in the adrenal gland and general disturbance of function of this gland, etc.
The vitamin constitutes part of an enzyme system. Combined with various substances including phosphate, adenylic acid, and a sulfhydryl group, it is coenzyme A, and this in combination with a protein is an enzyme capable of acetylating various organic substances such as choline and sulfanilamide. The acetylation of choline may be very important physiologically. How the acetylation, or rather the lack of it, can produce all the pathological conditions noted above is not clear, although in the case of the nervous system, any alteration of acetylcholine metabolism would certainly be harmful.
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