A Shuttle System for the Rapid Introduction of Tracking and other Genes into the Chromosomes of Soil Bacteria
The ability to easily and accurately track genetically engineered bacteria is an important aspect of their introduction into the environment. The genes introduced into these bacteria should also be inserted in such a way that their likelihood of loss or transfer to other bacteria is minimized. These two aims have been addressed for the fluorescent Pseudomonads by development of the Tn-derivative (Tn7-lac) gene insertion system that inserts the termini of the transposon but not those genes required for transposition. The genes (lacZY) that provide the phenotype used to select the recombinant derivatives also provide a phenotype that can be used very effectively in the tracking of these recombinant bacteria even in the presence of high numbers of similar indigenous bacteria. In the system above, the addition of other genes to the element (and then to the bacteria) was difficult, as was the introduction of plasmids of different incompatibilities into many target bacteria.