Adenosine 5 -phosphate-2 -amino acid

See also Adenosine Adenosine Phosphates Amino Acids Human Genome Project (The) and Proteins. 

CycHc adenosine monophosphate (cAMP), produced from ATP, is involved in a large number of ceUular reactions including glycogenolysis, Hpolysis, active transport of amino acids, and synthesis of protein (40). Inorganic phosphate ions are involved in controlling the pH of blood (41). The principal anion of interceUular fluid is HP (Pig. 3) (41). 

Brydon and Roberts- added hemolyzed blood to unhemolyzed plasma, analyzed the specimens for a variety of constituents and then compared the values with those in the unhemolyzed plasma (B28). The following procedures were considered unaffected by hemolysis (up to 1 g/100 ml hemoglobin) urea (diacetyl monoxime) carbon dioxide content (phe-nolphthalein complex) iron binding capacity cholesterol (ferric chloride) creatinine (alkaline picrate) uric acid (phosphotungstate reduction) alkaline phosphatase (4-nitrophenyl phosphate) 5 -nucleotidase (adenosine monophosphate-nickel) and tartrate-labile acid phosphatase (phenyl phosphate). In Table 2 are shown those assays where increases were observed. The hemolysis used in these studies was equivalent to that produced by the breakdown of about 15 X 10 erythrocytes. In the bromocresol green albumin method it has been reported that for every 100 mg of hemoglobin/100 ml serum, the apparent albumin concentration is increased by 100 mg/100 ml (D12). Hemolysis releases some amino acids, such as histidine, into the plasma (Alb). 

The carbonyl group of the amino acid is activated in equation 2.67 because it is bound to a good leaving group (the phosphate of AMP has a pKa of about 6 or 7) and it may be readily attacked by one of the hydroxyl groups of the ribosyl ring of the terminal adenosine of the tRNA. 

Toropov et al.76-79 developed QSPR models for the complexes of nine alkaline-earth and transition metals with some amino acids, phosphate derivatives of adenosine, and heterocyclic compounds based on topological indices. Although the numbers of examples in the datasets were big enough, 11076 and 150,79 they involved only a few different ligands (17 and 25 molecules, respectively). The validation calculations were performed on the test sets containing the same ligands as in the training sets, which could explain the well observed performance of the predictions.7679... 

Synthesis of peptides from amino acids in the solid state or in aqueous solution has been reported with the aid of ATP, Mg2 and free imidazole 34 36). a 4.5 % yield of glycine peptides has been reported in the solid state, 0.6 % yield in aqueous solution 36). Gly-N-pA is formed in a yield of 72.5 % from glycine and chemically synthesized ImpA in aqueous solution, pH 8.0, at room temperature 37). At initial of pH 6.0 glycyl 5 -adenylate (gly-O-pA) and 2 (3 )-0-glycyl adenosine 5 -phosphate (pA-g W are formed 37). 

It is reported that a purine-requiring mutant of Escherichia coli accumulated a substance related to 5-amino-iV-D-ribosyl-4-imidazolecarboxamide. Its ultraviolet absorption spectrum and its diazo chromogen spectrum differed from those of the known D-ribosyl derivative. Escherichia coli (strain B-96) converts it to 5-amino-4-imidazolecarboxamide, and it can be utilized by Escherichia coli B. It was suggested that it is an amino-(D-ribosyl)-imidazole. The accumulation of this substance was, however, somewhat surprising, since bacterial extracts of the purine-requiring mutant effected synthesis of 5-amino-4-imidazolecarboxamide from o-ribose 5-phosphate together with adenosine 5-triphosphoric acid and an energy source. 

Anhydrides between adenosine 5-phosphate and amino acids are believed to be intermediates in protein synthesis. They have also been shown to be present in bacteria. - The amino acid activation proceeds as follows. 

Subsequently, the functions of the vitamin were better established and requirements for the vitamin were set. Riboflavin is an Integral part of two coenzymes, flavin-5 -phosphate (FMN) and flavin adenine dinucleotide (FAD), which function in oxidation/reductlon reactions. Indeed, riboflavin is an enzyme cofactor which is necessary in metabolic processes in which oxidation of glucose or fatty acid is used for production of adenosine triphosphate (ATP) as well as in reactions in which oxidation of amino acids is accomplished. The minimum requirement for riboflavin has been established as that amount which actually prevents the signs of deficiency. A range of intakes varying from 0.55 to 0.75 mg/day of riboflavin has been established as the minimum amount which is required to prevent appearance of deficiency signs. 

Amino acyl adenylates are obtained in the reaction of adenosine 5-phosphate (ASP) with free amino acids in aqueous pyridine, mediated by DCC. The linkage is an anhydride between the amino acid carboxyl group and the phosphate in A5P." ... 

A.7.1 Esterification of Acids using Carbodiimides. The formation of anhydrides from carboxylic acids, thiocarboxylic acids, sulfonic acids and phosphorous acids are discussed in Section 2.4.S.2. In this section only special cases of anhydride formation are described. Mixed anhydrides of amino acids and adenylic acid are produced from the corresponding acids using DCC as the condensation agent. ° Mixed anhydrides not containing amino acids, such as butyryl adenate, adenosine 5 -phosphosulfate and p-nitrophenyl-thymidine-5-phosphate are also obtained. 

The application of LSR to amino-acids has received some attention. (451-456, 498) Such studies are an essential preliminary to the use of LSR for amino-acid sequence determination in simple peptides and proteins. The latter are discussed more comprehensively in Section G. A detailed study has been made (453) of the interaction of Eu(iii), Pr(iii), Gd(iii), and La(iii) with iV-acetyl-L-3-nitrotyrosine in order to characterize the nitrotyrosine residue as a potential specific lanthanide binding site in proteins. The parameters of the dipolar interaction indicate a significant contribution from non axially symmetric terms. The conformations of the nucleotides cyclic j8-adenosine 3, 5 -phosphate (3, 5 -AMP) (457, 458) and adenosine triphosphate (ATP) (459) have been deduced using LSR. In the former case the conformation of the ribose and phosphate groups is consistent with the solid state structure. A combination of lanthanide shift and relaxation reagents was used to deduce the most favoured family of conformations for ATP in aqueous solution. One of these conformations corresponds closely to one of the crystal structure forms. 

Histidine can be prepared from imidazole as in Scheme 117. It is a basic amino acid, the biosynthesis of which appears to involve adenosine 5 -phosphate, ribose phosphate and glutamine (which supplies a nitrogen for the imidazole ring) (Scheme 118). Histidine is one of the most important amino acids and has involvement in such biological processes as ester hydrolysis, acylation and (by virtue of its complexing power with iron) oxygen... 

The formation of vanadate esters with hydroxyl groups in aqueous solutions has been studied in detail for methanol (53), ethylene glycol (57), phenol, and tyrosine (58). Vanadate is able to form cyclic complexes when there are adjacent hydroxyls in the molecule (59) and interacts with luidine, adenosine monophosphate (60), glutathione disulphide (61), and phosphate (62). Rehder (63) studied the interaction of amino acids and dipeptides with vanadate. He concluded that complexes are formed in which the peptide function and the iV-terminal amino group are involved. Similarly, it was reported (64) that vanadate... 

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