Mutagenesis of dimeric plasmids by the transposon gamma delta (Tn1000).
The Escherichia coli F factor mediates conjugal transfer of a plasmid such as pBR322 primarily by replicative transposition of transposon gamma delta (Tn1000) from F to that plasmid to form a cointegrate intermediate. Although resolution of this cointegrate always yields a plasmid containing a single gamma delta insertion, the occasional recovery of transposon-free plasmids after conjugal transfer has led to alternative hypotheses for F mobilization. We show here that gamma delta-free plasmids are found after F-mediated conjugal transfer only when the donor plasmid is a dimer and the recipient is Rec+.
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Department of Molecular and Cell Biology, University of Connecticut, Storrs 06269-2131.
Berg
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CM
D003227:Conjugation, Genetic; D003433:Crosses, Genetic; D004251:DNA Transposable Elements; D004278:DNA, Superhelical / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics*; D005838:Genotype; D009154:Mutation; D010957:Plasmids
D004251:DNA Transposable Elements; D004278:DNA, Superhelical