Sensitivity and repair of bacteria and phages after exposure to far and near UV light

Inactivation of bacterial strains derived from E. coli B, which differ in the DNA-repair capacity (exc-, pol- and rec-) was investigated after far and near UV irradiation. The same strains were also used as hosts for UV-irradiated phage T7. The injuries caused in bacteria and phages by radiation with longer wavelengths were reparable with greater difficulty and only to a lesser extent by the investigated repair mechanisms. We suppose that near UV affects cell proteins and that, as a result of this damage, the DNA-repair systems may be inhibited.