Carcinogen-induced insertion mutations in E. coli.

M Takeshita; H Van der Keyl; A P Grollman

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PubMed · 2986166

Carcinogen-induced insertion mutations in E. coli.

M Takeshita·H Van der Keyl·A P Grollman

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Abstract

Mutagenic effects of AAF have been examined by transforming competent E. coli cells with plasmid DNA which were regionally-modified with this carcinogen. Transposition of IS5 from chromosomal DNA to target sequences in the AAF-modified region was detected in six plasmids obtained from wild type and recA strains. A single GC addition was identified in an additional plasmid; no deletions were detected. The observed frequency of IS5 insertion, 2.5 X 10(-3), exceeds that reported for naturally-occurring IS5 transposition in E.coli. These results suggest that the frequency of recombinational events in E.coli can be increased by the presence of a DNA-carcinogen adduct.

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Acetoxyacetylaminofluorene Base Sequence Carcinogens DNA Restriction Enzymes DNA Transposable Elements DNA, Bacterial Escherichia coli Mutation Transformation, Bacterial Journal Article Research Support, U.S. Gov't, P.H.S.

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M Takeshita, H Van der Keyl, A P Grollman. 1985. Carcinogen-induced insertion mutations in E. coli.. https://pubmed.ncbi.nlm.nih.gov/2986166/

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