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|Section2= |Section7= |Section9= }} Pantothenic acid, also called pantothenate or vitamin B5 (a B vitamin), is a water-soluble vitamin. For many animals, pantothenic acid is an essential nutrient. Animals require pantothenic acid to synthesize coenzyme-A (CoA), as well as to synthesize and metabolize proteins, carbohydrates, and fats. Pantothenic acid is the amide between pantoic acid and β-alanine. Its name derives from the Greek ''pantothen'' (), meaning "from everywhere", and small quantities of pantothenic acid are found in nearly every food, with high amounts in avocado, whole-grain cereals, legumes, eggs, meat, royal jelly, and yogurt.〔(【引用サイトリンク】title=Pantothenic Acid )〕 It is commonly found as its alcohol analog, the provitamin panthenol (pantothenol), and as calcium pantothenate. Pantothenic acid is an ingredient in some hair and skin care products.〔(【引用サイトリンク】 title=Soap, Detergent, Cosmetic Ingredients )〕 Pantothenic acid was discovered by Roger J. Williams in 1933. ==Biological role== Only the dextrorotatory (D) isomer of pantothenic acid possesses biologic activity.〔MedlinePlus. "Pantothenic acid (Vitamin-B5), Dexpanthenol". Natural Standard Research Collaboration. U.S. National Library of Medicine. Last accessed 4 January 2007. ()〕 The levorotatory (L) form may antagonize the effects of the dextrorotatory isomer. 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.〔Voet, D., Voet, J.G., Pratt, C.W. (2006). Fundamentals of Biochemistry: Life at the Molecular Level, 2nd ed. Hoboken, NJ: John Wiley & Sons, Inc.〕 CoA is important in energy metabolism for pyruvate to enter the tricarboxylic acid cycle (TCA cycle) as acetyl-CoA, and for α-ketoglutarate to be transformed to succinyl-CoA in the cycle.〔Gropper, S. S, Smith, J. L., Groff, J. L. (2009). Advanced nutrition and human metabolism. Belmont, CA: Wadsworth, Cengage learning.〕 CoA is also important in the biosynthesis of many important compounds such as fatty acids, cholesterol, and acetylcholine.〔 CoA is incidentally also required in the formation of ACP,〔Sweetman, L. (2005). Pantothenic Acid. Encyclopedia of Dietary Supplements. 1: 517-525.〕 which is also required for fatty acid synthesis in addition to CoA.〔 Pantothenic acid in the form of CoA is also required for acylation and acetylation, which, for example, are involved in signal transduction and enzyme activation and deactivation, respectively.〔Gropper, S. S, Smith, J. L., Groff, J. L. (2009). Advanced nutrition and human metabolism. Belmont, CA: Wadsworth, Cengage learning〕 Since pantothenic acid participates in a wide array of key biological roles, it is essential to all forms of life. As such, deficiencies in pantothenic acid may have numerous wide-ranging effects, as discussed below. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pantothenic acid」の詳細全文を読む スポンサード リンク
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