title: Further evidence that transposition of Tn5 in Escherichia coli is strongly enhanced by constitutively activated RecA proteins.
abstract: We have shown that excision and transposition of Tn5 in Escherichia coli are greatly increased by recA(Prtc) genes, which encode constitutively activated RecA proteins (C.-T. Kuan, S.-K. Liu, and I. Tessman, Genetics 128:45-57, 1991). Contrary results, showing a significant decrease in Tn5 transposition under SOS conditions, were subsequently reported (M. D. Weinreich, J. C. Makris, and W. S. Reznikoff, J. Bacteriol. 173:6910-6918, 1991). We have extended our studies to examine the following: (i) transposition of Tn5 from sites in the phoA, phoB, proC, trpD, and ilvD genes; (ii) the effect of gene transcription; (iii) the comparative effect of dinD+ and dinD(Def) alleles; (iv) the use of a mating-out assay of transposition; (v) the effect of a recA(Prtc) allele located at the normal chromosomal site; and (vi) the effect at 41.5 degrees C of the recA441(Prtc) allele. The new results fully confirm our previous conclusions, including the fact that the frequency of Tn5 transposition under constitutive SOS conditions is site dependent.
authors.affiliation: Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907.
authors.forename: C T
authors.initials: CT
authors.lastname: Kuan
authors.forename: I
authors.initials: I
authors.lastname: Tessman
mesh_terms: D000483:Alleles; D003433:Crosses, Genetic; D004251:DNA Transposable Elements / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D005144:F Factor / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics*; D011938:Rec A Recombinases / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D004251:DNA Transposable Elements; D011938:Rec A Recombinases