Mechanisms for radiation damage in DNA

Abstract

In this project we have proposed several mechanisms for radiation damage and recently radiation protection to DNA and its constituents, and have detailed a series of experiments utilizing electron spin resonance spectroscopy, HPLC, GC-mass spectroscopy and ab initio molecular orbital calculations to test the proposed mechanisms. In this years work we have performed experiments which elucidate the role of hydration water on DNA radiation damage, continued the investigation of the localization of the initial charges on DNA and employed ab initio molecular orbital theory to gain insight into the initial events of radiation damage to DNA. Ab initio calculations have provided an understanding of the energetics envolved in anion and cation formation, ion radical transfer in DNA as well as proton transfer with DNA base pair radical ions. This information has aided the formation of new radiation models for the effect of radiation on DNA. During this fiscal year four articles have been published, two are in press, two are submitted and several more are in preparation. Six papers have been presented at scientific meetings. This years effort includes a review article on the Chemical Consequences of Radiation Damage to DNA''. This review presents an overview of this field at this time.