Adenylic add

Poly(U) = poly(uridylic add), poly(l + C) = equimolar complex of poly(inosinic add) and poly(cytidylic add), poly (A + U) = equimolar complex of poly(adenylic add) and polyfnridylic add), RNA = polyribonucleic add, DNA = polydeoxyribonucleic add, dDNA = denatured DNA... 

Inosinic and Adenylic Adds, Similarly, Levene and Harris found that the adenylic acid from ribosenucleic acid can be deaminated to an inosinic acid which undergoes hydrolysis at its own pH to give hypo-xanthine and 3-phosphoribose. On the other hand, Thannhauser had shown that ammoniacal hydrolysis of the adenylic acid gives adenosine and phosphoric acid. 

RNA contains the nucleotide bases adenine (A), uracil (U), guanine (G), and cytosine (C). These bases are covalently attached to the ribose phosphate to form nucleotides. The respective nucleotides are called adenylic add (A), uridylic add (U), guanylic add (G), and cytidylic acid (C). 

Bovamick, M., Lindsay, A., and Hellerman, L. (1946). Metabolism of the malarial parasite, with reference particularly to the action of antimalarial agents. II. Atabrine (quinacrine) inhibition of glucose oxidation in parasites initially depleted of substrate. Reversal by adenylic add.. Biol. Chem. 163,535-551. 

Figure 2 indicates the broadening of the resonance of the deoxy forms of adenylic add (5 AMP) and thymidylic acid (5 TMP) as a result of complexation. At the top are the resonance peaks (A and C, respectively) in the absence of metal ions, and at the bottom are the resonance peaks (B and D, respectively) in the presence of added copper ions (i). This type of study indicates binding of copper to the phosphate. 

Alderson T (1961) Mechanism of mutagenesis induced by formaldehyde. The essential role of the 6-amino group of adenylic add (or adenosine) in the mediation of the mutagenic activity of formaldehyde. Nature (London) 191 251-253... 

It is known that the toxic action of 6-mercaptopurine can be prevented by injection of adenylic acid or by a number of related substances (214)-6-Mercaptopurine has been found to inhibit DPN synthesis in the liver of mice injected with nicotinamide (199). This inhibition can be antagonized by an administration of adenylic add. Similar results have been obtained with another purine antagonist, thioguanine. Both 6-mercaptopurine and thioguanine not only decrease the amount of DPN synthesis but also interfere with the return of the DPN to its normal value at the end of the 24-hr period. The difference at 24 hr for 6-mercaptopurine was found to be as great as fivefold. The effect of the drug on the return to normal levels is not reversed by the introduction of adenylic acid. 

Inosinic add is the parent substance of the two purine nucleotides adenosine 5 -phosphate adenylic add) and guanosine 5 -phosphate (guanylic add), both components of nucleic acids. It is also the parent compound of uric acid, which is the final excretion form of nitrogen in birds and in reptiles. 

Note that the first step in Figure 21.6—reaction of the carboxylate with ATP to give an acyl adenylate—is itself a nucleophilic acyl substitution on phosphorus. The carboxylate first adds to a P=0 bond, giving a five-coordinate phosphorus intermediate that expels diphosphate ion as leaving group. 

SCHLESINGER, D. H., GOLDSTEIN, G., and Niall, H. D. The complete amino add sequence of ubiquitin, an adenylate cydase stimulating polypeptide probably universal in living cells, Biochemistry, 1975, 14, 2214-8. 

ADENOSINE PHOSPHATES. The adenosine phosphates include adenylic acid (adenosine monophosphate, AMP) in which adenosine is esteri-fied with phosphoric add at the 5/-position adenosine diphosphate (ADP) in which esterification at the same position is with pyrophosphoric acid,... 

ADENINE. [CAS 73-24-5]. A prominent member of the family of naturally occurring purines (see Structure 1). Adenine occurs not only in ribonucleic adds (RNA), and deoxyribonucleic acids (DNA). but in nucleosides, such as adenosine, and nucleotides, such as adenylic acid, which may be linked with enzymatic functions quite apart from nucleic adds. Adenine, in the form of its ribonucleotide, is produced in mammals and fowls endogenously from smaller molecules and no nutritional essentiality is ascribed to it. In the nucleosides, nucleotides, and nucleic acids, the attachment or the sugar moiety is at position 9. 

The structure of firefly luciferin has been confirmed by total synthesis. The firefly emits a ycllow-grccn luminescence, and luciferin in this case is a benzthiazole derivative. Activation of the firefly luciferin involves the elimination of pyrophosphate from ATP widi the formation of an add anhydride linkage between the carboxyl group of luciferin and the phosphate group of adenylic acid forming luciferyl-adenylate. 

FIGURE 26-1 Mechanism of action of beta agonists on respiratory smooth muscle. Beta agonists facilitate bronchodilation by stimulating adenyl cyclase activity, which in turn increases intracellular cyclic AMP production. Cyclic AMP activates protein kinase, which appears to add an inhibitory phosphate group to contractile proteins, thus causing muscle relaxation and bronchodilation. 

Acidic proteinoid potentiates the active structure of lysine-rich proteinoid participating in forming microspheres in neutral buffer. Physical surface effects and providing micro condition in the microspheres could be surmised. Activation of amino acids generally requires acidic condition. Amino acids are activated by ATP and Mg2+ at pH 4-5 32 33). Aminoacyl adenylate anhydride and ester is formed preferentially from amino acid and adenylate imidazolide at pH 6.0J7). On the other hand, polycondensation of activated amino acids undergoes at pH values higher than 7. Peptides are formed from aminoacyl adenylate in basic buffer (the optimum pH is 10 for alanyl adenylate 40) from amino acid adenylate phosphoramidate and imidazole at pH 7.0 from N-(aminoacyl)-imidazole at pH 6-9 43). In this context, acidic and basic environments may be provided inside and/or on the surface of the microspheres composed of acidic and basic proteinoids in neutral buffer. Acidic micro condition suitable for the activation of amino acids and basic micro environment favorable for peptide formation from activated amino add may be provided. 

Intron sequences contain some common features. Most introns begin with the sequence GT (GU in RNA) and end with the sequence AG. Otherwise, very little similarity exists among them. Intron sequences may be large relative to coding sequences in some genes, over 90 percent of the sequence between the 5 and 3 ends of the mRNA is introns. RNA polymerase transcribes intron sequences. This means that eukaryotic mRNA precursors must be processed to remove introns as well as to add the caps at the 5 end and poly adenylic acid (poly A) sequences at the 3 end. 

Figure 4.2 Gastric add production. Two cell types in the mucosa of the corpus of stomach are principally responsible for secretion of acid. Histamine secreted from nearby enterochromaffin-like (ECL) cells stimulates parietal cells to secrete acid. A variety of substances can stimulate the ECL cell to secrete histamine, including PCAP, pituitary adenyl cyclase-activab ng peptide (released from enteric nervous system interneurones in the gastric mucosa), and gastrin, both stimulating ECL cells via adenyl cyclase to raise intracellular levels of cAMP that lead to histamine secretion.

Whereas cholera is a result of a G protein trapped in the active conformation, causing the signal-transduction pathway to be perpetually stimulated, pertussis, or whooping cough, is a result of the opposite situation. Pertussis toxin also adds an ADP-ribose moiety,— in this case, to a G j protein, a G protein that inhibits adenyl cyclase, closes Ca + channels, and... 

Figure 28.25. Polyadenylation of a Primary Transcript. A specific endonuclease cleaves the RNA downstream of AAUAAA. Poly(A) polymerase then adds about 250 adenylate residues.

Murayama T, and Ui M. (1987). Ihosphatidic add may stimulate menibrane receptors mediating adenylate cyclase inhibition and phospholipid breakdown in 3T3 fibroblasts. J. Biol. Chem. 262, 5522-5529. 

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