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Indirect ultraviolet-reactivation of phage lambda.

J George·R Devoret·M Radman
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Abstract

When an F(-) recipient Escherichia coli K12 bacterium receives Hfr or F-lac(+) DNA from an ultraviolet-irradiated donor, its capacity to promote DNA repair and mutagenesis of ultraviolet-damaged phage lambda is substantially increased. We call this phenomenon indirect ultraviolet-reactivation, since its features are essentially the same as those of ultraviolet-reactivation; this repair process occurs in pyrimidine dimer excision-deficient strains and produces clear plaque mutations of the restored phage. Moreover, this process is similar to indirect ultraviolet-induction of prophage lambda, since it is promoted by conjugation. However, contrarily to indirect induction, it is produced by Hfr donors and occurs in recipients restricting the incoming ultraviolet-damaged donor DNA. The occurrence of indirect ultraviolet-reactivation provides evidence for the existence in E. coli of an inducible error-prone mechanism for the repair of DNA.

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ColiphagesConjugation, GeneticDNA RepairDNA, ViralEscherichia coliLysogenyMutationUltraviolet RaysViral Plaque AssayJournal Article

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J George, R Devoret, M Radman. 1974. Indirect ultraviolet-reactivation of phage lambda.. https://doi.org/10.1073/pnas.71.1.144

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