Human Biochemistry, Volume 2 - Murray R. 1993

Structure, Function, and Replication of Information Macromolecules
Metabolism of Purine and Pyrimidine Nucleotides
Biomedical Significance

Neither NUCLEOTIDES themselves nor the dietary purine and pyrimidine bases entering The Human Body are incorporated into human tissue Nucleic Acids or into purine or pyrimidine Coenzymes such as ATP or NAD. Even when the diet is rich in Nucleoproteins, human Cells nevertheless synthesize nucleic acid precursors from amphibolic intermediates. The de novo synthesis pathway allows synthetic purine and pyrimidine analogues with antineoplastic properties to be incorporated into DNA.

The rate of Synthesis of purine and pyrimidine ribo- and deoxyribonucleotides is subject to fine regulation. Mechanisms have evolved to ensure a level of production of these compounds over time that meets the constantly changing physiological needs of the Organism. Alongside de novo synthesis, so-called Salvage Pathways operate, allowing the reutilization of purine and pyrimidine bases released from nucleic acids during in vivo degradation. DISEASES ASSOCIATED WITH Disorders of purine and pyrimidine METABOLISM include Gout, Lesch-Nyhan syndrome, Reye's syndrome, adenosine deaminase deficiency, and purine nucleoside phosphorylase deficiency.