title: The formation of photoreactivable damage by direct excitation of DNA in X-irradiated E. coli cells.
abstract: The role of the direct excitation process in the formation of photoreactivable damage (pyrimidine dimers) in E. coli WP2 hcr-exr- cells has been studied. The pyrimidine dimers were detected by photoreactivation following anoxic irradiation by X-rays (220 kVp). The dose modifying factor (DMF) is 1.28 +/- 0.09. A biophysical model is used for a theoretical examination of the importance of the direct excitation process in the formation of photoreactivable damage and the experimental data are consistent with this model.
mesh_terms: D004260:DNA Repair; D004269:DNA, Bacterial / Q000528:radiation effects*; D004926:Escherichia coli / Q000528:radiation effects*; D008027:Light; D008433:Mathematics; D008954:Models, Biological; D011831:Radiation Genetics; D014466:Ultraviolet Rays
chemical_list: D004269:DNA, Bacterial