Initial Sites of One Electron Attachment in DNA

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


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.


Electron Affinity Initial Site Electron Attachment Electron Trapping Electron Abstraction 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

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

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