Pantothenic acid essentiality

Biosynthesis of coen2yme A (CoA) ia mammalian cells incorporates pantothenic acid. Coen2yme A, an acyl group carrier, is a cofactor for various en2ymatic reactions and serves as either a hydrogen donor or an acceptor. Pantothenic acid is also a stmctural component of acyl carrier protein (AGP). AGP is an essential component of the fatty acid synthetase complex, and is therefore requited for fatty acid synthesis. Free pantothenic acid is isolated from hver, and is a pale yeUow, viscous, and hygroscopic oil. 

The 4-phosphopantetheine group of CoA is also utilized (for essentially the same purposes) in acyl carrier proteins (ACPs) involved in fatty acid biosynthesis (see Chapter 25). In acyl carrier proteins, the 4-phosphopantetheine is covalently linked to a serine hydroxyl group. Pantothenic acid is an essential factor for the metabolism of fat, protein, and carbohydrates in the tricarboxylic acid cycle and other pathways. In view of its universal importance in metabolism, it is surprising that pantothenic acid deficiencies are not a more serious problem in humans, but this vitamin is abundant in almost all foods, so that deficiencies are rarely observed. 

In terms of amino acids bacterial protein is similar to fish protein. The yeast s protein is almost identical to soya protein fungal protein is lower than yeast protein. In addition, SCP is deficient in amino acids with a sulphur bridge, such as cystine, cysteine and methionine. SCP as a food may require supplements of cysteine and methionine whereas they have high levels of lysine vitamins and other amino acids. The vitamins of microorganisms are primarily of the B type. Vitamin B12 occurs mostly hi bacteria, whereas algae are usually rich in vitamin A. The most common vitamins in SCP are thiamine, riboflavin, niacin, pyridoxine, pantothenic acid, choline, folic acid, inositol, biotin, B12 and P-aminobenzoic acid. Table 14.4 shows the essential amino acid analysis of SCP compared with several sources of protein. 

Pantothenic acid is an essential component of coenzyme A (CoA) (Fig. 2) and - as pantetheine - of fatty acid synthase. The HS-group of cysteamine is... 

Pantothenic acid and biotin were thus found to be growth factors for yeast. Like riboflavin these molecules are incorporated into larger molecules in order to exert their essential metabolic function. Unlike the other vitamins there has been no evidence of pathological signs in man which can be attributed to dietary deficiencies in biotin or pantothenic acid. 

More than most of us can hope for, Williams life was also filled with extraordinary gifts and accomplishments. For over 20 years he and his co-workers worked to discover, isolate, characterize and synthesize the substance he named pantothenic acid, an essential cog in the biochemical machinery of all living things. He also first concentrated and named folic acid, another B vitamin. As founder and director of the Clayton Foundation Biochemical Institute at the University of Texas at Austin from 1940 to 1963, he and his colleagues made many other notable contributions to nutrition and biochemistry. 

RDA have been established for many essential nutrients however, present knowledge of human nutritional needs of pantothenic acid and biotin is incomplete. Therefore, to ensure adequate nutrient intake, obtain the recommended allowances from as varied a selection of foods as possible. Nutritionists suggest that dietary planning include regular intake of each of the four basic food groups ... 

Pantothenic acid is a vitamin, which is essential to human life. Its name is derived from a Greek root that reflects its universal occurrence in living things. The bacterium Lactobacillus bulgaricus, which converts milk... 

Attachment of phosphopantetheine to proteins is catalyzed by a phosphotransferase that utilizes CoA as the donor. A phosphodiesterase removes the phosphopantetheine, providing a turnover cycle.15, 5b A variety of synthetic analogs have been made.4 16 The reactive center of CoA and phosphopantetheine is the SH group, which is carried on a flexible arm that consists in part of the (3-alanine portion of pantothenic acid. A mystery is why pantoic acid, a small odd-shaped molecule that the human body cannot make, is so essential for life. The hydroxyl group is a potential reactive site and the two methyl groups may enter into formation of a "trialkyl lock" (p. 485), part of a sophisticated "elbow" or shoulder for the SH-bearing arm. 

In 1901. Wildiers described Bios, an essential for yeast growth. In 1933. Williams isolated crystalline Bios from yeast and named it pantorhemc acid. In 1938, Williams isolated pantothenic acid from liver and. in 1939, Jukes determined liver antidermatitis factor (chick) to be identical with yeast factor. Also, in 1939, Woolley et al. demonstrated beta-alanine as a vital part of pantothenic add ... 

This is followed by removal of the glutamic acid and the glycine residues, which is followed by acetylation of the remaining cysteine. Essential amino acids are required for the synthesis of the proteins involved, pantothenic acid for coenzyme A synthesis, and phosphorus for synthesis of the ATP needed for glutathione synthesis. Similar scenarios can be developed for glucuronide and sulfate formation, acetylation, and other phase II reaction systems. 

D-Pantothenic acid is also traditionally produced by chemical processes which involve efficient but troublesome and costly crystallization of diastereomeric salts of pantoate and chiral amines. After lactonization of the isolated D-pantoate, d-pantolactone is reacted with / -alanine to give D-pantothenate. Because the monovalent salts of pantothenic acid are highly hygroscopic, conversion into the calcium salt is essential for convenient formulation. The third class of synthetic processes for optically active compounds makes use of biotechnology. For natural com-... 

The discovery, isolation and final synthesis of a whole group of new compounds essential to health in a balanced diet was another triumph of the chemist. These compounds called vitamins A, Ba or G, C, D, E, K, and several others closely associated with vitamin Ba, such as niacin, pantothenic acid, inositol, para-amino benzoic acid, choline, pyndoxine (Be), biotin (H), folic acid and Bn, prevent deficiency diseases such as xerophthalmia (an eye disease), beriberi, pellagra, scurvy, rickets, sterility (in rats), excessive bleeding and so forth. Professors Elmer V. McCollum and Herbert M. Evans, and Joseph Goldberger were among the early American pioneers in this field of research. Drugs, anaesthetics, and medicines like procaine, cyclopropane, dramamme, ephedrine, aspirin, phenace-tin, urotropin, veronal, quinine, and strychnine have been synthesized to alleviate the pains of mankind. The essential... 

In pantothenic acid-deficient rats, tissue CoA is depleted, affecting mainly the peroxisomal oxidation of fatty acids, which is mainly concerned with detoxication mitochondrial /3 -oxidation, which is an essential energy-yielding pathway, is spared to a great extent (Youssef et al., 1997). However, relatively moderate deficiency in animals results in increased plasma triacylglycerol and nonesterifled fatty acids, suggesting some impairment of lipid metabolism (Wittwer et al., 1990). 

Saliha Ki, Horner HA, and Kirk K (1998) Transport and metaholism of the essential vitamin pantothenic acid in human erythrocytes infected with the malaria parasite Plasmodium falciparum. Journal of Biological Chemistry 273,10190-5. 

The organic compounds other than the essential amino acids which are required for health are called vitamins. Man is known to require at least thirteen vitamins Vitamin A, (thiamine), Bo (riboflavin), Bg (pyridoxin), B.o, C (ascorbic acid), D, K, niacin, pantothenic acid, inositol, para-aminobenzoic acid, and biotin. 

Pantothenic acid, C9H17O3N occurs in Coenzyme A (p. 1173), essential to metabolism of carbohydrates and fats. It reacts with dilute NaOH to ivR CvHi OsNNa, with ethyl alcohol to give C11H21O5N, and with hot NaOH to give compound V (see below) and -aminopropionic acid. Its nitrogen is non-basic. Pantothenic acid has been synthesized as follows ... 

Pantothenic acid and its derivatives have essentially no pliarmacological actions per se. Because of the ubiquitous nature of the vitamin, deficiency stales usually do not develop. They have been produced by u.se of synthetic diets devoid of the vitamin or by use of a vitamin antagonist. [Pg.888]

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