Radiation damage to DNA

Evans, H.H. 1990. Ionizing radiation mutagenesis in mammalian cells. Pages 211-219 in UCLA Symposia Colloquium. Ionizing Radiation Damage to DNA Molecular Aspects. Wiley-Liss, New York. 

The rate and extent of electron and hole migration within DNA had been a topic of intense experimental [1] and theoretical [2] interest and dispute. However, as other chapters in this volume point out, the overall picture is now becoming increasingly understood. Several earlier reviews have dealt with the radiation damage to DNA and subsequent chemical processes including electron and hole transfer [3]. This chapter will focus on recent contributions to hole and electron transfer in DNA from high-energy radiation studies. We first present a brief overview on electron transfer processes in DNA from radiation studies and describe in more detail our most recent results on electron and hole transfer in DNA at low temperatures. 

Product analysis shows that the oxidative pathway of direct radiation damage to DNA results in a variety of products from each of the DNA bases [18] however, the dominant products are those from guanine such as 8-oxo-guanine and fapy-guanine as expected from the overall charge transport to guanine [18]. 

ESR Studies of Radiation Damage to DNA and Related Biomolecules Table III Radicals found in Purine Single Crystals... 

Barvian MR, Barkley RM, Greenberg MM (1996) Reactivity of 5,6-dihydro-5-hydroxythymid-6-yl generated via photoinduced single electron transfer and the role of cyclohexa-1,4-diene in the photodeoxygenation process. J Am Chem Soc 117 4894-4904 Becker D, Sevilla MD (1997) Radiation damage to DNA and related biomolecules. Electron Spin Re-son 16 79-115... 

Russo N, Toscano M, Grand A (2000) Theoretical determination of electron affinity and ionization potential of DNAand RNA bases. J Comput Chem 21 1243-1250 Sagstuen E, Hole EO, Nelson WH, Close DM (1998) Radiation damage to DNA base pairs. II. Paramagnetic resonance studies of 1 -methyluracil. 9-ethyladenine complex crystals X-irradiated at 10 K. Radiat Res 149 120-127... 

Cullis PM, Langmann S, Podmore ID, Symons MCR (1990) Effects of ionizing radiation on deoxyribonucleic add. Part VI. - Effects of hydroxyl radical scavengers on radiation damage to DNA. J Chem Soc Faraday Trans 86 3267-3271... 

Ward JF, Blakely WF, Joner El (1985) Mammalian cells are not killed by DNA single-strand breaks caused by hydroxyl radicals from hydrogen peroxide. Radiat Res 103 383-392 Ward JF, Webb CF, Limoli CL, Milligan JR (1990) DNA lesions produced by ionizing radiation Locally multiply damaged sites. In Wallace SS, Painter RB (eds) Ionizing radiation damage to DNA Molecular aspects. Wiley-Liss, New York, pp 43-50... 

The long-standing interest of Boyd and his coworkers in radicals and radical ions has led to many papers since 1993 on hyperfine structures. These papers have pushed the conventional multireference configuration interaction methods to the limits of the available computers, tested the predictive ability of various functionals commonly used in DFT calculations, and, among other topics, modeled the effect of a noble gas matrix on the hyperfine structures of radicals. Recent research focused primarily on radicals formed as a consequence of radiation damage to DNA. 

Radiotherapeutics attack cancer by causing radiation damage to DNA in cells. The requirements differ from those for drug delivery because the radiotherapeutic can act at a distance and does not have to separate from the delivery particle. Radiotherapeutics can be selected to provide action over a range of distances, from tens of nanometers to hundreds of microns. Three radiotherapy modalities can be identified. Brachytherapy, most often used with beta-emitters, uses tightly enclosed radioactive material that is brought in close proximity to the tumor. A second modality is intravenous injection so that the radiopharmaceutical binds to the outside of the tumor cells or is taken up by the cell and irradiates from within. The third approach uses a carrier loaded with the radiotherapeutic that is transported to the vicinity of the target cells, and then released. 

Keywords Radiation Damage to DNA, EPR/ENDOR Spectroscopy, Primary Radiation Induced... 

In order to understand the effects of radiation damage to DNA it is necessary to consider larger model systems such as nucleotides, base pairs, and stacked bases. The question then becomes whether or not it is possible to do reliable calculations on such large systems. The literature is full of various attempts to study these complex systems. Some attempts have been more successful than others. 

This review has spanned many years of work devoted to the attempts to understand the effects of radiation damage to DNA. The emphasis has been on the use of EPR/ENDOR spectroscopy to reveal the structures of the primary radiation induced products in DNA. ENDOR was invented before 1960, but it took quite some time before this technique was used to study problems in radiation biology. The basic reason is that complex equipment had to be designed and tested that permits the irradiation and examination of small single crystals at helium temperatures. The apparatus was only completed around 1975 by Bernhard and co-workers in Rochester, and by Huttermann and co-workers in Regensburg. 

Sevilla MD, Becker D (2004) ESR studies of radiation damage to DNA and related biomolecules. In Royal Society of Chemistry Special Periodical Report, Electron Spin Resonance, London, Vol. 19, p 243. 

Becker D, Sevilla MD (1993) The chemical consequences of radiation damage to DNA. In Lett J (ed.) Advances in Radiation Biology, Vol. 17, Academic Press, New York, p 121. 

A Multi-Component Model For Radiation Damage To DNA From Its Constituents... 

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