Abstract
Exploring electronic states of DNA is essential to understand the interaction between the molecule and charged particles in a track of ionizing radiation. Photoabsorption cross section of DNA, which is strongly involved in oscillator strength distribution, has been investigated because the cross section should reflect the electronic and excitation states of DNA. On the other hand, it has been reported that a hole created on DNA by radiation could migrate to a guanine site and induce an oxidative base lesion such as 8-oxo-G. Localization of the lesion at guanine sites can be interpreted as an effect of its relatively lowest ionization potential value (oxidation trend; G>A>C>T). Recent results obtained from spectroscopic studies and theoretical calculations on the electronic states of DNA will be presented. These newly introduced methods are becoming powerful techniques to reveal the mechanism of DNA damage and damage repair process by enzymes. [J Radiat Res 44:380-381 (2003)]
