Adenosine-5 -phosphate enzymatic synthesis

Adenylic Acid. Muscle adenylic acid ergaden -ylic acid t -adenylic acid adenosine S -monophosphate adenosine phosphate adenosine-5 -phosphoric add edeno-sine-5. monophosphoric acid A5MP AMP NSC-20264 Addiyl Cardiomone (Na salt) Lycedan My -B-Den My-oston Phosaden. C,0HhNjO7P mol wt 347.23, C 34.59%, H 4.06%, N 20.17%, O 32,25%, P 8,92%. Nucleotide widely distributed in nature. Prepn from tissues Embden, Zimmerman, Z. Physrot Chem. 167, 137 (1927) Embden, Schmidt, ibid. 181, 130 (1929) cf. Kalckar, J. B.ol Chem. 167, 445 (1947). Prepn by hydrolysis of ATP with barium hydroxide Kerr, 3. Biot Chem. 139, 13l (1941). Synthesis Baddiley, Todd. 3. Chem. Soc. 1947, 648. Commercial prepn by enzymatic phosphorylation of adenosine. Monograph on synthesis of nucleotides G. R. Pettit. Synthetic Nucleotides vol, 1 (Van Nostrand-Reinhold. New York, 1972) 252 pp. Crystal structure Kraut, lensen, Acta Cryst 16, 79 (1963). Reviews see Adenosine Nucleic Acids. 

Structure of Coemyme A. The elucidation of the structure of CoA depended heavily on d radation by specific enzymes. The phosphate on carbon 3 of the adenosine was shown to be a monoester phosphate by hydrolysis with prostate phosphomonoesterase. The localization of the monoester at the 3 position was established by its sensitivity to a b nucleotidase that attacks only nucleoside 3 -pbosphates, not 2 - or 5 -phosphates. The original CoA molecule or the phosphatase product, depbospho CoA, can be split by nucleotide pyrophosphatases from potato or snake venom. These reactions permitted the identification of the adenosine phosphate portion of the molecule. The position of the phosphate on pantothenic acid cannot be determined enzymatically, but was established by studies on the synthesis of CoA from synthetic phos-phorylated pantetheines. Pantetheine is split to thiolethanolamine and pantothenic acid by an enzyme found in liver and kidney. This enzyme also attacks larger molecules, including CoA. 

One of the best examples of an enzymatic dephosphorylation for a synthetic purpose is shown in the entry 5 ofTable 13-6. A 5 -ribonucleotide phosphohydrolase was used in the synthesis of (-)-aristeromycin, a carbocyclic analog of adenosine. The (-)-enantiomer of aristeromycin shows some cytostatic and antiviral activity, while the (+)-enantiomer is inactive. The racemate ( )-5 -phosphorylated aristeromycin was resolved by selective hydrolysis of the (-)-enantiomer with the hydrolase. The (-)-alcohol and the (+)-5 -phosphate derivative were separated easily on a silica gel column. Hydrolysis of the (-t-)-enantiomer with calf intestinal phosphatase yielded pure (+)-alcohol. 

Phytoene synthase is encoded by the closely related bacterial crtB and eukaryotic psy genes. The phytoene formed in the enzymatic reaction was present in both a 15-cw and all-trans isomeric configuration. The essential cofactors required were adenosine triphosphate (ATP) in combinations with either Mn + or Mg +. Phytoene synthesis was inhibited by phosphate ions and squalestatin. 

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