Cytidine-5 guanosine-3 3-phosphate

Clindamycin (93 R = H), an antibiotic obtained by chlorinating linco-mycin, is converted by a species of Streptomyces into inactive phosphorus-containing compounds. These have been shown to be nucleoside 5 -phosphates derived from adenosine, cytidine, guanosine, and uridine. 

Adenosine 5 -phosphate Guanosine 5 -phosphate Cytidine 5 -phosphate Uridine 5 -phosphate... 

Nucleosides (e. g. adenosine, cytidine, guanosine, pyrimidine, thymidine, uridine) consist of a nitrogenous purine or pyrimidine base linked to a 5-carbon sugar (ribose or deoxyribose). Nucleotides (adenine, cytosine, guanine, thymine, uracil), the phosphate esters of nucleotides, form the basis of RNA and DNA. As infectious viral nucleic acids, they are capable of penetrating the cells and using available enzyme systems for replication. 

Involved in energy transfer in biochemical reactions. Uridine, cytidine, guanosine and thymine triphosphates are also common in biological systems. Nicotinamide adenine dinucleotide phosphate is also an important energy carrier. 

Cytidine 2, 3 -cyclicphosphate, polymeric complexes of Cd" and Cu" and cytidine 5 -phosphate, l-(j8-D-arabinofuranosyl)cytosine Pt complex. Adenosine complexed with 5-bromouracil, iS-methyl-5 -thioadenosine, 2, 3 -0-isopropyIideneadenosine, 2, 3 -0-(2-carboxyethyl)ethylideneadeno-sine, the amino-acid adenosine derivatives (5) and (6) which are constitutents of tRNA, 8-[(2-aminoethyl)amino]adenosine 3, 5 -cyclic phosphate. 8-Iodoguanosine, 2-JV-methylguanosine, a guanosine Hg" complex, 2, 35 -tri-(9-acetyl-6-0-(mesitylenesulphonyl)-guanosine, guanosine 5 -phosphate, Cu" complex. ... 

Prepare individual standards (Sigma) of adenosine-5 -phosphoric acid, cytidine 5 -phosphate (sodium salt), guanosine-5 -phosphate (sodium salt), and uridine-5 -phosphate (disodium salt) as l-pg/p. solutions in deionized water. Prepare each standard by dissolving 10 mg of the nucleotide in 10 ml of water. Prepare a mixed standard of the four nucleotides at 1 Ag/)il for each. To obtain the mixed standard, weigh 10 mg of each nucleotide and dissolve in 10 ml of water to achieve a concentration of 1 )ig/ J.l for each. 

The following separations (approximate values included) will be achieved for both individual nucleotides and the mixed standard guanosine-5 -phosphate (sodium salt), 0.34 adenosine-5 -phosphoric acid, 0.48 cytidine-5 -phosphate (sodium salt), 0.60 and uridine-5-phosphate (disodium salt), 0.74. The compounds will appear as dark spots against a bright fluorescent background at 254 nm. 

The 5 -Substituted Nucleotides. These are adenosine-5 -phosphate, guanosine-5 -phosphate, uridine-5 -phosphate, and cytidine-5 -phosphate. All of them have been found among the hydrolysis products when ribonucleic acid is treated with snake venom diesterase or with intestinal phosphatase in the presence of arsenate. These compounds contain phosphate esterified at carbon 5 of the ribose moiety. 

Bull seminal plasma also contains 5-nucleotidase activity. The enzyme has been purified from this source and found to split adenosine-5 -phosphate, uridine-5 -phosphate, cytidine-5 -phosphate, guanosine-5 -phosphate, and nicotinamide-ribose-5 -phosphate. Of several dozen other esters, only the desoxyribonucleotides have been found active as substrates. Snake venom contains a highly specific 5-nucleotidase which can be separated from phosphodiesterase by means of cellulose column chromatography. ... 

This compound has been isolated after subjecting yeast ribonucleic acid to brief acid hydrolysis. When it is treated with alkali there is cleavage at (1), with the formation and subsequent hydrolysis of a cyclic anhydride of guanylic acid. The final products are guanosine-2 -phosphate, guanosine-3 -phosphate, and cytidine-3 -phosphate. The last two would be split by 3-nucleotidase from barley. 

Intestinal mucosa enzyme partially inhibited by arsenate leads to the formation of guanosine, cytidine, and cytidine-5 -phosphate. This preparation splits at (2) with subsequent partial dephosphorylation. Snake venom diesterase also sphts at (2). Prostatic phosphatase liberates... 

The enzyme purified from bull semen dephosphorylates the 5 -phosphate esters of adenosine, uridine, cytidine, guanosine, nicotinamide riboside, and the 5 -phosphate esters of deoxynucleosides, but is inactive with adenosine pyrophosphates and substrates which bear other substituents on the ribose, e.g., adenosine 2, 5 -diphosphate (124). However 5 -nucleo-tidase from potato can hydrolyze the 5 -phosphate of this diphosphate... 

FIGURE 10.8 Langmuir adsorption isotherms of nucleosides on Spherisorb ODS-2 from 25mM phosphate buffer (pH 7.0) at 25°C. (A) Adenosine, (A) guanosine, (o) cytidine, ( ) uridine. (Reprinted from Huang, J.X. and Horvath, Cs., J. Chromatogr., 406, 275, 1987. With permission from Elsevier.)... 

The sugar nucleotides (an uninformative name that has been used for glycosyl nucleotides, or more strictly, glycosyl esters of nucleoside di- or mono-phosphates) were discussed in this Series12 in 1973. Since then, accumulation of new data about these derivatives has continued, and now, about 35 representatives of this class are known to participate in the biosynthesis of polysaccharide chains of bacterial polymers (for a survey, see Ref. 13). These include glycosyl esters of uridine 5 -diphosphate (UDP), thymidine 5 -diphosphate (dTDP), guanosine 5 -diphosphate (GDP), cytidine 5 -diphosphate (CDP), cytidine 5 -monophosphate (CMP), and adenosine 5 -diphosphate (ADP). 

The sequence of nucleotides is described by starting at the 5 phosphate end and identifying the bases in order. Abbreviations are used for each nucleotide A for adenosine, G for guanosine, C for cytidine, T for thymidine, and U for uracil. Thus, a typical DNA sequence might be written as -T-A-G-G-C-T-. 

Brunner, C., Seiderer, J., Schlamp, A, Bidlingmaier, M., Eigler, A, Haimerl, W. et al. (2000) Enhanced dendritic cell maturation by TNF-alpha or cytidine-phosphate-guanosine DNA drives T cell activation in vitro and therapeutic anti-tumor immune responses in vivo. J. Immunol., 165, 6278-6286. 

If we attach the nitrogenous bases to a ribose, we have the RNA nucleosides. The four RNA nucleoside bases are adenosine, uridine, cytidine, and guanosine. Usually, these nitrogenous bases are represented as A, U, C, and G, respectively. Figure 12.69 gives the names and structures of these compounds. Addition of a phosphate group to carbon 5 of the ribose sugar affords the RNA nucleotide bases. 

---