FLEXIBILITY AND THERMAL DENATURATION (MELTING) OF IRRADIATED DNA

Abstract

The study of the melting transition for large molecular weight DNA which had been irradiated with various doses of γ-rays can yield information on the structural and dynamical behaviour of DNA, leading to a better understanding of changes induced by external agents. In order to interpret the accumulated experimental data, a theoretical description capable of correlating thermal changes to those induced by ionizing radiation, is required. The theoretical ideas proposed here, based on first principles and certain assumptions, allow for a quantitative analysis of the melting data and the subsequent evaluation of a very small number of parameters which can be used to interpret the observed variations in experimental quantities (such as UV absorbance) which are related to structural variations.