Uridine-5 -monophosphate, structure

In nature, eight common nucleotides exist, four found in DNA and four in RNA. In the standard abbreviations for DNA nucleotides, a lowercase d specifies the presence of deoxyribose. RNA nucleotides lack this designation. Nucleosides have names of one word (e.g., deoxyadenosine, cytidine, and uridine). The ending monophosphate completes the nucleotide names. Table 16.1 lists correct names for all common nucleotides and nucleosides, and Figure 16.9 shows linkages and structures for all eight nucleotides. 

THYMIDINE KINASE (TK) An enzyme involved in the utilization of the nucleoside thymidine (which ultimately becomes part of the structure of DNA) catalyzes the phosphorylation of thymidine to thymidine monophosphate mutants that lack TK are resistant to the toxic effects of several thymidine analogues, including bromodeoxy-uridine and trifluorothymidine selection of these drug-resistant mutants provides the basis of several... 

If the crystal structures and hydrogen-bonding patterns of uridine and thymidine and their simpler derivatives are compared with those of cytidine, it becomes obvious that the -NH2 functional group has a characteristic influence. The nucleosides without the -NH2 groups have less than average hydrated crystals, although the one nucleotide represented, uridine-3 -monophosphate, crystallizes as a monohydrate. 

Write the structure that results when adenosine-5 -monophosphate is linked by a 3 — 5 phosphodiester bond to uridine-5 -monophosphate. 

Uridylic Acid. Uridine 5 -phosphoric acid uridine 5 -monophosphate UMP. C,H,2N20,P mol wt 324.19, C 33.34%, H 4.047=, N 8.64%, O 44.42%, P 9.56%-. Nucleotide widely distributed in nature. Synthesis by phos, phorylation of 2, 3 -O-benzylidene uridine with diphenyl phosphorochloridate Brown et aL, J. Chem. Soc. 1950, 408 Smith, Biochem. Prepn. 8, 130 (i960. Monograph on the synthesis of nucleotides G. R Pettit, Synthetic Nucleotides vol. 1 (Van Nostrand Reinhold, New York, 1972) 252 pp. Crystal structure of hydtated barium salt Shelter, True-blood, Acta Cryst. 18, 1067 (1965). Reviews see Uridine Nucleic Acids. 

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