Illegitimate recombination in an Escherichia coli plasmid: modulation by DNA damage and a new bacterial gene.
AUTOR(ES)
Yi, T M
RESUMO
We studied DNA rearrangements in Escherichia coli by using a plasmid-based system with a transcriptionally silent tet gene and selecting for Tetr isolates. The predominant activating event was a 1.3-kilobase-pair deletion in the plasmid between two sites, with 14 of 19 base pairs being identical. These deletions occurred equally frequently in a recA+ strain and a recA13 mutant. However, the frequency of Tetr occurrence was stimulated 50-fold by treatment of the cells with UV light in a process that was at least partly independent of the SOS response. Bacterial mutants deleted for the xth-pnc region of the chromosome exhibited a strongly elevated spontaneous frequency of Tetr isolates, all with the same 1.3-kilobase-pair deletion. This phenotype of high-frequency deletion could be complemented by an episome covering this region, but not by the cloned xth gene. These studies helped to define the role of different DNA damages in illegitimate recombination and identify a region of the E. coli chromosome that contains a gene whose product normally suppresses illegitimate deletions.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=211227Documentos Relacionados
- Illegitimate Recombination Induced by Overproduction of DnaB Helicase in Escherichia coli
- Vaccinia DNA topoisomerase I promotes illegitimate recombination in Escherichia coli.
- Genetic recombination of bacterial plasmid DNA: effect of RecF pathway mutations on plasmid recombination in Escherichia coli.
- Illegitimate recombination mediated in vitro by DNA gyrase of Escherichia coli: structure of recombinant DNA molecules.
- RecQ DNA helicase is a suppressor of illegitimate recombination in Escherichia coli