An important aspect of Synthetic Biology is to prevent the uncontrolled interaction between the genetically modified organismen and the environment and mankind. For this approach there are a lot of ideas in discussion to implement different Biosafety-Systems (Quelle) in synthetic Biology to prevent this interaction on one hand. On the other hand there are several studies dealing with the interaction of genetically modified bacteria and natural wild types, demonstrating in most cases that genetically modified bacteria does not influence the environment. Because the genetically modified bacteria are adapted to the excellent conditions of the laboratory, the natural bacteria will usually outlast these modified strains in nature due to their better adaptation to their environment. But there is always a risk remaining and no guarantee that there is really no interaction and that their release does not affect the equilibrium of the environment (Myhr et. al 1999).
So the most problematic factor in this case is the transfer of synthetic or genetically modified DNA, particularly the transfer of antibiotic-resistance, because a genetic exchange of the antibiotic-resistance is an active intervention in the environment.
Therefore we want to establish an antibiotic-free selection system, which opens the possibility of using genetically organism with a reduced remaining risk to the environment, due to the antibiotic-free selection. This antibiotic-free selection system can be used for molecular cloning as well as long-term plasmid stability and on top it turned out, that it is even more efficient than the selection using the antibiotic chloramphenicol...