Pantothenic occurrence

Recently, Prasad et al. cloned a mammalian Na+-dependent multivitamin transporter (SMVT) from rat placenta [305], This transporter is very highly expressed in intestine and transports pantothenate, biotin, and lipoate [305, 306]. Additionally, it has been suggested that there are other specific transport systems for more water-soluble vitamins. Takanaga et al. [307] demonstrated that nicotinic acid is absorbed by two independent active transport mechanisms from small intestine one is a proton cotransporter and the other an anion antiporter. These nicotinic acid related transporters are capable of taking up monocarboxylic acid-like drugs such as valproic acid, salicylic acid, and penicillins [5], Also, more water-soluble transporters were discovered as Huang and Swann [308] reported the possible occurrence of high-affinity riboflavin transporter(s) on the microvillous membrane. 

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... 

During the 1930s. R. J. Williams and his collaborators recognized. isolated, and synthesized pantothenic acid. Because its occurrence is so widespread, it was called panioihenic acid from the Greek, meaning "from everywhere."... 

Pantothenic acid is of ubiquitous occurrence in nature, where it is synthesized by most microorganisms and plants fi-om pantoic acid (D-2,4-dihydroxy-3,3-dimethylbutyric acid) derived from L-vafine, and p-alanine derived from L-aspartate. Addition of cysteamine at the C-terminal end and phosphorylation at C4 of pantoic acid forms 4 -phosphopantetheine, which serves as a covalently attached prosthetic group of acyl carrier proteins, and, when attached... 

Hedley and Yudkin (1959) reported that the inclusion of 10% sorbitol in the diets of young rats prevented the occurrence of signs of pantothenic acid deficiency such as decreased weight gain. Similar results were reported by Herndon et al. (1959). 

Williams, R.J., Eyman, C.M., Goodyear, G.H., Truesdail, H.T., and Holaday, D., 1933. Pantothenic acid, a growth determinant of universal biological occurrence. Journal of the American Chemical Society. 55 291-292. 

While the apparently ubiquitous occurrence of pantothenic acid was a striking fact in 1933, this is not now regarded so, because many other chemical substances, notably other B vitamins, are also widely distributed in many diverse forms of life. The widespread occurrence of pantothenic acid has led... 

In medical circles the importance of pantothenic acid as a nutrient is often disregarded because of this universal-occurrence idea and also because it is difficult to produce inhumansaspecificdiseasecondition whichmay be attributed specifically to its deficiency. It would appear that pantothenic acid deficiency (since it is the only organic part of coenzyme A needed nutritionally by mammals) might well cause diffuse adverse effects comparable to those which might be expected to occur in non-osseous tissues as a result of phosphate deficiency. 

The role of pantothenic acid in human nutrition has not been established. It is of wide natural occurrence, as the name implies. Metabol-ically, pantothenic acid seems to have some special role in the adrenals, and this may be a link with acetylation mechanisms in the synthesis of steroids (Hughes, 1953). The burning feet" syndrome encountered in prisoners of war and other malnourished groups has been specifically treated with pantothenic acid (Gopalan, 1946). The figures given by Williams et al. (1950) for B vitamins in different foods and tissues can be considered to show a ratio of pantothenic acid to thiamine, riboflavin, and niacin at an amount about half that of the niacin, but ten times the thiamine. No precise requirement can be stated. 

Pantothenic acid in food is determined with microbiological or ELISA (cf. 2.6.3) techniques. A gas chromatographic method using a C-isotopomer of pantothenic acid as the internal standard is very accurate and much more sensitive. Table 6.7 lists data on pantothenic acid occurrence in food. 

The existence of pantothenic acid as a B-group vitamin, a dietary factor, whose absence caused a form of dermatitis in chicks, was anticipated around 1930 and discovered in 1931 by Williams (2,9). The name pantothenic acid, given to the active substance by Williams and his coworkers in 1933 (10), indicated its widespread occurrence in nature. The structure of pantothenic acid (Fig. 1) was established by Williams in 1938 (11) and the total synthesis was first achieved by the US Merck group in 1940 (12). 

RJ Williams, EM Bradway. The further fractionation of yeast nutrilites and their relationship of vitamin B and Wilders bios. J Am Chem Soc 53 783-789,1931. RJ Williams, CM Lyman, GM Goodyear, JE Truesdayl, D Holaday. Pantothenic acid a growth determinant of universal biological occurrence. J Am Chem Soc 55 2912-2927, 1933. 

The combination of pantoic acid (a,7-dihydroxy- 8,/3-dimethylbutyric acid) and 8-alanine is also called pantothenic add, this name is derived from its nearly universal occurrence. Pantothenic acid is listed as one of the B vitamins. Pantothenic acid deficiency in experimental animals produces various symptoms (chicken pellagra, graying of hair in the rat) but in man deficiency diseases are not known. 

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