Pantothenic acid coenzyme A

Pantothenic acid Coenzyme A Transfer of acetyl groups... 

Pantothenic acid Coenzyme A Acyl-group transfer Hypertension... 

Biosynthesis of coenzyme A (CoA) in mammalian cells incorporates pantothenic acid. Coenzyme A, an acyl group carrier, is a cofactor for various enzymatic reactions and serves as either a hydrogen donor or an acceptor. Pantothenic acid is also a stmctural component of acyl carrier protein (ACP). ACP is an essential component of the fatty acid synthetase complex, and is therefore required for fatty acid synthesis. Free pantothenic acid is isolated from hver, and is a pale yellow, viscous, and hygroscopic oil. 

Thiamine pyrophosphate has two important coenzyme roles, both of which focus mostly on carbohydrate metabolism (Figs. 8.26 and 8.27). The active portion of the coen- rae is the thiazole ring. The first step in the oxidative decarboxylation of a-keto acids requires TPP. The two most common examples are pyruvate and a-ketoglutarate, oxidatively decarboxyatedto acetyl CoA and succinyl CoA, respectively. The same reaction is found in the metabolism of the branched-chain amino acids valine, isoleucine, leucine, and methionine. In all cases, TPP is a coenzyme in a mitochondrial multienzyme complex, consisting of TPP, lipoic acid, coenzyme A, FAD, and NAD. Note the number of vitamins required for the oxidative decarboxylation of a-keto acids thiamine (TPP), pantothenic acid (coenzyme A), riboflavin (FAD),and niacin (NAD). 

The chemistry of the cofactors has provided a fertile area of overlap between organic chemistry and biochemistry, and the organic chemistry of the cofactors is now a thoroughly studied area. In contrast, the chemistry of cofactor biosynthesis is stiU relatively underdeveloped. In this review the biosynthesis of nicotinamide adenine dinucleotide, riboflavin, folate, molyb-dopterin, thiamin, biotin, Upoic acid, pantothenic acid, coenzyme A, S-adenosylmethionine, pyridoxal phosphate, ubiquinone and menaquinone in E. coli will be described with a focus on unsolved mechanistic problems. 

Pantothenic acid Coenzyme A Acyl group (i) Pantothenic acid Beet molasses PtnicUlium spent mycelium Cornsteep liquor Coiionse flour... 

Alanine is found in the vitamin pantothenic acid, coenzyme A, and in some important natural peptides. It is... 

Pantothenic acid Coenzyme A Fatty acid oxidation. 5-10 mg... 

The first active form of pantothenic acid, coenzyme A (CoA, CoASH), was isolated and identified as the acyl transfer agent in two-carbon unit metabolism... 

Vitamin B5 occurs in three biologically active forms in foods [1] pantothenic acid, coenzyme A (CoA), and acyl carrier protein (ACP). Calcium or sodium pantothenate are the forms generally used as supplements in infant formula [4], The total quantification of vitamin B5 requires the release of pantothenic acid from CoA and ACR Since it consists of pantoic acid linked through an amide linkage to p-alanine, chemical hydrolysis cannot be used. The only alternative to free pantothenic acid from CoA is the digestion with a number of enzymes (pepsin, alkaline phosphatase, pantetheinase) nevertheless, this treatment is unable to release the vitamin from ACP [27,28]. For the extraction of free pantothenic acid from milk and calcium pantothenate from infant formula an acidic deproteination is often used, followed by centrifugation and filtration [29,30]. 

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