Radical effects on mutation spectra in lambda phage.

H Bertram; U Hagen

doi:10.1080/09553009214551771

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PubMed · 1353773

Radical effects on mutation spectra in lambda phage.

H Bertram·U Hagen

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Abstract

Mutations in the lambda repressor gene cI (710 bp) were induced by 60Co-gamma radiation in dissolved lambda phage DNA. After in vitro DNA packaging to lambda phage particles (pack phage) and phenotypic expression of the mutants, DNA was sequenced directly. Two-thirds of mutations were located in the amino terminus region of the gene without any signs of hotspots. Changes consisted of (+1) insertions (25%) and base substitutions (75%). Transitions were exclusively G/C to A/T. Transversions were mostly G/C to C/G and few G/C to T/A. We did not find A/T to T/A transversions, A/T to G/C transitions, deletions and gross rearrangements. In most of the base substitutions a pre-existing base pair had been replaced by an A/T pair; this might come from 'non-instructional sites' like abasic sites. Several mechanisms for base substitutions are considered.

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Bacteriophage lambda Base Sequence Cobalt Radioisotopes DNA, Viral Gamma Rays Molecular Sequence Data Mutation Journal Article

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H Bertram, U Hagen. 1992. Radical effects on mutation spectra in lambda phage.. https://doi.org/10.1080/09553009214551771

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