Heat-sensitive Radiation Damage in Single-stranded DNA Irradiated in a Bacterial Extract

Summary

The effect of heat treatment (45°C) on γ-irradiated biologically active single-stranded ϕX174 DNA, dissolved in a bacterial extract, was studied. The results show that under these circumstances heat-sensitive damage is found, which is absent after irradiation in pure buffer. The damage is non-lethal and probably becomes an apurinic/apyrimidinic site, which is lethal, upon the post-irradiation heat treatment. Prolonged heating converts it into a break. The amount of the initial damage depends on the conditions of irradiation.