Stimulation of recombination between homologous sequences on plasmid DNA and chromosomal DNA in Escherichia coli by N-acetoxy-2-acetylaminofluorene

C. Luisi-DeLuca, R. D. Porter, W. D. Taylor

Research output: Contribution to journalArticlepeer-review

24 Scopus citations

Abstract

A plasmid containing a wild-type lac operon and a tetracycline-resistance gene was covalently modified by N-acetoxy-2-acetylaminofluorene and used to transform two series of Lac- Escherichia coli cell types. Each set contained wild-type and repair-deficient mutants. One set of cells contained a lacY mutation and other a deletion of the entire lac operon. Survival and mutagenesis of the plasmid were measured as a function of the N-acetoxy-2-acetylaminofluorene concentration. The results indicate that when no homologous sequences are present in the chromosomal DNA, mutations occur at a low frequency: at 10% survival the frequency was 1-2 x 10-4 mutants per transformant. When homologous sequences, the lacY allele, are present in the chromosomal DNA, Lac- plasmids are found at a high frequency in a recA-dependent, lexA-independent fashion: at 10% survival the frequency was 5-10 x 10-2 mutants per transformant. Southern blot analysis of the restriction enzyme profiles of the resulting plasmid and the host-cell DNA sequences showed recombinational transfer of host sequences to the N-acetoxy-2-acetylaminofluorene-treated plasmid had occurred. When the host chromosomes contained Lac+ homologous sequences no mutants were found, indicating that the results were not caused by error-prone recombination.

Original languageEnglish (US)
Pages (from-to)2831-2835
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Volume81
Issue number9 I
DOIs
StatePublished - 1984

All Science Journal Classification (ASJC) codes

  • General

Fingerprint

Dive into the research topics of 'Stimulation of recombination between homologous sequences on plasmid DNA and chromosomal DNA in Escherichia coli by N-acetoxy-2-acetylaminofluorene'. Together they form a unique fingerprint.

Cite this