Nucleotides: Uncommon, Modified and Synthetic


Many types of modified nucleotides exist naturally or are the products of laboratory syntheses.

Keywords: nucleic acids; DNA; RNA; oligonucleotides

Figure 1.

Representative modified and hypermodified nucleobases found in tRNA: dihydrouridine [I], 5‐carboxymethyluridine [II], 2‐thiouridine [III], pseudouridine [IV], 5‐methylcytidine [V], archaeosine [VI], N1‐methylguanosine [VII], N6‐dimethallyladenosine [VIII], and wybutosine [IX].

Figure 2.

Representative sugar‐modified nucleic acids: 4′,6′‐methano DNA analogue [X], 3′,5′‐ethano DNA analogue [XI], homo‐DNA [XII] and hexitol nucleic acid analogue [XIII].

Figure 3.

Representative backbone‐modified nucleic acids: peptide nucleic acid [XIV], and morpholino nucleic acids [XV].



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Further Reading

Adams RLP, Knowler JT and Leader DP (1992) The Biochemistry of the Nucleic Acids, 11th edn. London: Chapman and Hall.

Bjork GR (1995) Genetic dissection of synthesis and function of modified nucleosides in bacterial transfer RNA. Progress in Nucleic Acid Research and Molecular Biology 50: 263–339.

De Clercq E (1992) HIV inhibitors targeted at the reverse transcriptase. AIDS Research and Human Retroviruses 8: 119–134.

Demple B and Harrison L (1994) Repair of oxidative damage to DNA: enzymology and biology. Annual Review of Biochemistry 63: 915–948.

Englisch U and Gauss DH (1991) Chemically modified oligonucleotides as probes and inhibitors. Angewandte Chemie, International Edition in English 30: 613–629.

Eschenmoser A (1992) Chemistry of potentially prebiological natural products. Chemical Society Reviews 21: 1–16.

Herdewijn P (1996) Targeting RNA with conformationally restricted oligonucleotides. Liebigs Annalen September: 1337–1348.

Huryn DM and Okabe M (1992) AIDS‐driven nucleoside chemistry. Chemical Reviews 92: 1745–1768.

Isono K (1991) Current progress on nucleoside antibiotics. Pharmacology and Therapeutics 52: 269–286.

Usman N, Beigelman L and McSwiggen JA (1996) Hammerhead ribozyme engineering. Current Opinion in Structural Biology 6: 527–533.

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How to Cite close
Switzer, Christopher(Apr 2001) Nucleotides: Uncommon, Modified and Synthetic. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0001334]