Vectors for Transposon Mutagenesis of Non-enteric Bacteria

We have constructed a series of transposon delivery vectors derived from pRK2013. Since pRK2013 has a broad host range transfer system and a ColE1 replicon, it can be transferred to, but not replicated in, many non-enteric gram-negative bacteria. Thus pRK2013 provides an effective mechanism for the transient introduction of a transposon. Delivery vectors containing Tn7 (tmp str), Tn10 (tet), Tn10 HH104 (tet), or Tn5-132 (tet) have been constructed. When transposition in Caulobacter crescentus was examined, both Tn7 and Tn5-132 were found to transpose efficiently. In contrast, although the antibiotic resistances of Tn10 and Tn501 (mer) were expressed in C. crescentus, no transposition was observed with either transposon. However, transposition of Tn10 from the Tn10 vectors did occur in Acinetobacter calcoaceticus, and transposition of Tn501 from pMD100 has been demonstrated in Rhizobium japonicum (Bullerjahn and Benzinger 1984). Thus, transposon-host interactions play an important role in the determination of whether a particular transposon can transpose in a given host. Furthermore, the results with C. crescentus indicate that there must be different requirements for host interactions for Tn10 and Tn501 than for Tn5 and Tn7.