Ultraviolet light-induced mutagenesis in the Escherichia coli chromosome. Sequences of mutants in the cI gene of a lambda lysogen.
DNA sequences were determined for 56 mutations induced by ultraviolet light in the lambda cI gene of an Escherichia coli uvr+ lysogen, which should reflect those occurring in the E. coli chromosome. The spectrum of mutagenesis was similar to that found in the cI gene of irradiated phase assayed in uvr- host cells, except that the fraction of transversions is about 35% in prophage and about 15% in phage. The cause of this difference is not known. Of 17 frameshifts in phage and prophage, six have an accompanying base substitution. These double mutational events are consistent with a model in which a photoproduct in a template can cause a DNA polymerase to insert a wrong base and destabilize the next few bases added, thus leading to a frameshift by a slippage mechanism.
Wood
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Hutchinson
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D001482:Base Composition; D001483:Base Sequence; D002876:Chromosomes, Bacterial / Q000528:radiation effects*; D004269:DNA, Bacterial; D004926:Escherichia coli / Q000528:radiation effects*; D005798:Genes, Bacterial / Q000528:radiation effects; D008242:Lysogeny; D009154:Mutation; D014466:Ultraviolet Rays
D004269:DNA, Bacterial