title: W-reactivation of phage lambda in X-irradiated mutants of Escherichia coli K-12.
abstract: The survival of UV irradiated phage lambda was increased on X-irradiated E. coli K-12 host cells over that on unirradiated cells. The frequency of c mutants among the surviving phages was to a similar extent increased by the X-ray exposure of the host cells as by UV light. This W-reactivation of phage lambda occurred in uvrA, polA, and recB mutants besides the wild type at about equal X-ray doses, however, at a reduced reactivation efficiency compared with the wild type. W-reactivation was undetectable in recA mutants. While maximal UV induced W-reactivation occurred 30 min after irradiation, the maximal X-ray induced reactivation was found immediately after irradiation. Chloramphenicol (100 micrograms/ml) and nitrofurantoin (50 micrograms/ml) inhibited W-reactivation of phage lambda if added before irradiation of the host cells, indicating the necessity of protein synthesis for W-reactivation.
mesh_terms: D010582:Bacteriophage lambda / Q000187:drug effects / Q000528:radiation effects*; D002701:Chloramphenicol / Q000494:pharmacology; D004926:Escherichia coli / Q000528:radiation effects; D009154:Mutation; D009582:Nitrofurantoin / Q000494:pharmacology; D014466:Ultraviolet Rays; D014775:Virus Activation / Q000528:radiation effects*; D014965:X-Rays
chemical_list: D002701:Chloramphenicol; D009582:Nitrofurantoin