Polynucleotides biological synthesis

The chemical synthesis involves a lot more selective manipulation of functional groups, particularly by protection, than is necessary in the biological synthesis. However, this synthesis paved the way to the simple syntheses of nucleotides and polynucleotides carried out routinely nowadays. The usual method is to build short runs of nucleotides and then let the enzymes copy them—a real partnership between biology and chemistry. 

Azaguanine was the first purine analogue shown to be incorporated into polynucleotides [337] and, since its primary metabolic effect is on protein synthesis, the incorporation into RNA is considered the basis for its biologic activity [338]. In microbial systems 8-aza-adenine, 8-azahypoxanthine, 8-azaxanthine, and 5(4)-amino-l/f-l, 2, 3-triazole-4(5)-carboxamide are all incorporated into RNA as 8-azaguanylic acid [336]. 

Schuchmann MN, Naumov S, Schuchmann H-P, von Sonntag J, von Sonntag C (2005) 4-Amino-3Ff-pyrimidin-2-one ("isocytosine") is a short-lived non-radical intermediate formed in the pulse radiolysis of cytosine in aqueous solution. Radiat Phys Chem 72 243-250 Schulte-Frohlinde D, Hildenbrand K (1989) Electron spin resonance studies of the reactions of OH and SO4 radicals with DNA, polynucleotides and single base model compounds. In Minisci F (ed) Free radicals in synthesis and biology. Kluwer, Dordrecht, pp 335-359 Schulte-Frohlinde D, Behrens G, Onal A (1986) Lifetime of peroxyl radicals of poly(U), poly(A) and single- and double-stranded DNA and the rate of their reaction with thiols. Int J Radiat Biol 50 103-110... 

Olovnikov AM. 1973. A theory of marginotomy. The incomplete copying of template margin in enzymic synthesis of polynucleotides and biological significance of the phenomenon. J. Theor. Biol. 41 181-90... 

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