Use of a Tn5 derivative that creates lacZ translational fusions to obtain a transposition mutant

Gene. 1988 Mar 31;63(2):277-85. doi: 10.1016/0378-1119(88)90531-8.


We constructed a derivative of Tn5, Tn5 ORFlac, that is capable of creating lacZ translational fusions upon transposition. Lac- strains carrying this construct formed red papillae when plated on MacConkey-lactose media. Lac+ cells isolated from independent papillae expressed distinct beta-galactosidase fusion proteins, suggesting that the Lac+ phenotype resulted from transposition. In support of this, analysis of plasmids carrying Tn5 ORFlac prepared from these cells indicated that the Lac+ phenotypes arose as a result of intermolecular rearrangements. Furthermore, a derivative of Tn5 ORFlac that contains an ochre mutation in the transposase gene formed papillae only in a supB strain. Tn5 ORFlac is useful for obtaining mutants that affect Tn5 transposition and for creating lacZ fusions. We used the papillation phenotype to isolate a spontaneous revertant of IS50L that promotes transposition at a 3.6-fold higher rate than IS50R. The mutation altered the amino acid sequence of both transposase and inhibitor.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Base Sequence
  • DNA Transposable Elements*
  • Escherichia coli / genetics*
  • Genes, Bacterial*
  • Molecular Sequence Data
  • Mutation*
  • Plasmids
  • Protein Biosynthesis*


  • DNA Transposable Elements