Initial Sites of One Electron Attachment in DNA

  • William A. Bernhard
Part of the NATO ASI Series book series (volume 54)

Abstract

Chemical alterations in DNA, due to the direct effects of ionizing radiation, are initiated by three possible actions: excitation, electron abstraction, or electron addition. It is generally assumed, but unproved, that excitation events are negligible and that 50% of the damage stems from one-electron reduction and 50% stems from one-electron oxidation (Bernhard, 1981). Here the focus will be on the one-electron reduction of DNA, specifically the initial sites of attachment by unsolvated electrons. Ideally the initial distribution of electron attachment should be measured at very short times (<10–12 s) under physiological conditions. Instead, we use low temperatures (<4K) to freeze out highly unstable events. This affords the advantage of giving ample time to make measurements but, of course, leaves uncertainties because low temperatures do not necessarily capture the short lived events of high temperatures.

Keywords

Sugar Migration Quartz Hydrated Adduct 

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References

  1. Al-Kazwini AT, O’Neill P, Adams GE, Fielden EM (1990) Radiation-induced energy migration within solid DNA: the role of mizonidazole as an electron trap. Radiat Res 121: 149–153PubMedCrossRefGoogle Scholar
  2. Bernhard WA (1981) Solid state radiation chemistry of DNA: the bases. Adv Radiat Biol 9: 199–280Google Scholar
  3. Bernhard WA (1989) Sites of electron trapping in DNA as determined by ESR of one-electron-reduced oligonucleotides. J Phys Chem 93: 2187–2189CrossRefGoogle Scholar
  4. Bernhard WA (1990) Protonation of the cytosine radical anion. Radiat Res, submittedGoogle Scholar
  5. Bernhard WA and Patrzalek AZ (1989) ESR characteristics of one-electron reduced thymine in monomer, oligomer, and polymer derivatives. Radiat Res 117: 370–394CrossRefGoogle Scholar
  6. Berthod H, Gressner-Prettre C, Pullman A (1966) Theoretical study of the electronic properties of the purine and pyrimidine components of the nucleic acids. I. A semi-empirical sef-consistent-field calculation. Theor Chim Acta 5: 53–68CrossRefGoogle Scholar
  7. Bodor N, Dewar MJS, Harget AJ (1970) Ground states of conjugated molecules. XIX. Tautomerism of heteroaromatic hydroxy and amino derivatives and nucleotide bases. J Am Chem Soc 92: 2929–2936CrossRefGoogle Scholar
  8. Cullis PM, Podmore I, Lawson M, Symons MCR, Dalgarno B, McClymont J (1989) The site of electron capture in irradiated deoxyribonucleic acid: cytosine vs. thymine. J Chem Soc Chem Commun 1003–1005Google Scholar
  9. Gräslund A, Ehrenberg A, Rupprect A, Ström G (1975) Ionic base radicals in gamma-irradiated oriented non-deuterated and fully deuterated DNA. Int J Radiat Biol 28: 313–323CrossRefGoogle Scholar
  10. Gregoli S, Olast M, Bertinchamps A (1977) Charge migration phenomena in gamma-irradiated costacking complexes of DNA nucleotides. I. A computer-assisted ESR analysis of dAMP:dTMP complexes in frozen solution. Radiat Res 70: 255–274PubMedCrossRefGoogle Scholar
  11. Gregoli S, Olast J, Bertinchamps AJ (1982) Radiolytic Pathways in gamma-irradiated DNA: influence of chemical and conformational factors. Radiat Res 89: 238–254PubMedCrossRefGoogle Scholar
  12. Hüttermann J, Voit K, Oloff H, Ktthnlein W, Graslund A, Rupprecht A (1984) Specific formation of electron gain and loss centres in x-irradiated oriented fibres of DNA at low temperatures. Faraday Discuss Chem Soc 78: 135–149PubMedCrossRefGoogle Scholar
  13. Mercer K and Bernhard WA (1987) Design and operation of a variable temperature accessory for Q-band ESR. J Mag Res 74: 66–71CrossRefGoogle Scholar
  14. Saenger W (1984) Principles of Nucleic Acid Structure, Springer-Verlag, New York Berlin Heidelberg TokyoCrossRefGoogle Scholar
  15. Sevilla MD, Fallor R, Clark C, Holroyd RA, Pettel M (1976) Electron transfer in dinucleoside phosphate anions. J Phys Chem 80: 353–358CrossRefGoogle Scholar
  16. Steenken S (1989) Purine bases, nucleosides and nucleotides: aqueous solution redox chemistry and transformation reactions of their radical cations, e-, and OH adducts. Chem Rev 89: 503–520CrossRefGoogle Scholar
  17. Steenken S (1990a) Coupled electron and proton transfer reactions of nucleic acid bases. Abst 38th Ann Meet Radiat Res Soc p55, ch-3Google Scholar
  18. Steenken S (1990b) private communication, van Lith D, Warman JM, de Haas MP, Hummel A (1986) Electron migration in hydrated DNA and collagen at low temperatures. Part 1. effect of water concentration. J Chem Soc Faraday Trans 1, 82: 2933–2943Google Scholar
  19. van de Ven JM and Hilbers CW (1988) Nucleic acids and nuclear magnetic resonance. J Biocnem 178: 1–38Google Scholar
  20. Whillans DW (1975) Studies of electron migration in DNA in aqueous solution using intercalating dyes. Biochim Biophys Acta 414: 193–205PubMedGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • William A. Bernhard
    • 1
  1. 1.University of RochesterRochesterUSA

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