title: Isolation of transposon TnA from plasmid RP4 carrying two copies of this element.
abstract: Employing heteroduplex and restriction analyses, two inverted copies of a 3.2.10(6) dalton transposable sequence, TnA, were found in RP4::TnA, a spontaneously arisen derivative of the plasmid RP4. Integration of the second copy of TnA causes loss of the conjugative properties of RP4. Both TnA sequences in RP4::TnA were localized and found to have opposite orientations. The DNA fragment corresponding to the individual transposon TnA was isolated after the endonuclease S1 digestion of RP4::TnA molecules annealed under conditions favoring intramolecular renaturation. The attempts to transform the cells of Escherichia coli QD5003, HB101[pCRI] and JC7623 with the isolated transposon were unsuccessful.
mesh_terms: D004261:DNA Replication; D004262:DNA Restriction Enzymes / Q000378:metabolism; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000302:isolation & purification*; D004926:Escherichia coli / Q000235:genetics; D008854:Microscopy, Electron; D009690:Nucleic Acid Conformation; D011815:R Factors; D014169:Transformation, Bacterial
chemical_list: D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004262:DNA Restriction Enzymes