Molecular analysis of lambda bio transducing phage produced by oxolinic acid-induced illegitimate recombination in vivo.
To study the mechanism of DNA gyrase-mediated illegitimate recombination in Escherichia coli, we examined the formation of lambda Spi- phage during prophage induction. The frequency of Spi- phage was two to three orders of magnitude higher in the presence of oxolinic acid, an inhibitor of DNA gyrase A subunit, than in the absence of the drug, while it was very low in nalAr bacteria with the drug. RecA function is not required for the formation of these phages, indicating that this enhancement is not caused by the expression of SOS-controlled genes. Analyses of att region and recombination junctions of Spi- phages revealed that they have essentially the same structures as lambda bio transducing phages but are classified into two groups with respect to recombination sites. In the majority class of the transducing phages, there were not more than 3-bp homologies between the parental E. coli bio and lambda recombination sites. In the minority class of the transducing phages, on the other hand, 9-10-bp homologies were found between the parental recombination sites. These results suggested that oxolinic acid-induced illegitimate recombination takes place by two variants of a DNA gyrase-dependent mechanism.
Shimizu
H
H
Department of Molecular Biology, University of Tokyo, Japan.
Yamaguchi
H
H
Ikeda
H
H
D010582:Bacteriophage lambda / Q000187:drug effects / Q000235:genetics*; D001483:Base Sequence; D004250:DNA Topoisomerases, Type II / Q000378:metabolism*; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D005814:Genes, Viral; D005838:Genotype; D008969:Molecular Sequence Data; D010093:Oxolinic Acid / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic / Q000187:drug effects*; D013014:SOS Response, Genetics; D012689:Sequence Homology, Nucleic Acid; D014161:Transduction, Genetic
D004279:DNA, Viral; D004250:DNA Topoisomerases, Type II; D010093:Oxolinic Acid