Influencing of ionizing radiation on herpes simplex virus and its genome

The effects of cobalt-60 γ-rays, 10 MeV electrons and 52 MeV deuterons on the survival of plaque-forming ability has been studied in various strains of herpes simplex virus (HSV). The results show that the Dsub(o) for the loss of plaque-forming ability in different HSV strains lies in the range 1-3 kGy. Irradiation of isolated HSV-1 DNA with cobalt-60 γ-rays resulted in damage, as indicated by electrophoresis of purified viral DNA and by restriction endonuclease analysis, at doses of 1 kGy, with complete loss of structure at doses above 4 kGy, but after irradiation of the intact virus some plaque-forming ability was retained after doses of 10 or even 40 kGy. Thus the organization within the viral capsid may play a protective role by modifying the severity of the radiation damage, and preserving at least some degree of infectivity. (author)