Introduction
The use of MightyColi in the society does not raise too many questions: genetically modified microorganisms (GMM) are already used daily (and safely) in the pharmaceutical industry.
However, we realized that few people were aware of it, and still mingled GMM with the synthetical plants used in agriculture, which have a really bad reputation in western Europe. Although, Mighty Coli would be welcomed in the industry, we feared that if for some reason had to ask the authorization of the public to use Mighty Coli, we would only face fear, incomprehension, and eventually refusal. Since some people firmly believe that the use of synthetical organisms is an important ethical and societal issue, and that the general public should be included in the debate, we decided to organize several popularization events about this subject.
On the other hand, if we consider the biosecurity issues raised by our project, we can conclude that since Mighty Coli is only able to improve the production yield of a protein, the main issues that could be raised by Mighty Coli really depend on the chosen protein rather than Mighty Coli in itself. However, one could argue that a Mighty Coli bacterium that would somehow escape from a bioreactor would not be able to lose its ability to overproduce the chosen protein, which could lead to various pollution of the environment depending on the chosen protein.
As a conclusion, we choose to address two different issues in our human practice: the first is the popularization and the public awareness of GMM in particular; the second is the biosecurity measures that should be taken in order to use Mighty Coli responsibly.
Popularization events
After discussion within the team and with our friends and families, we decide that the themes of our popularization events would be the use of GMMs in research and industry (and the role that Mighty Coli could play in it), the means and perspectives of genetic manipulations and synthetic biology
We settled on two types of popularization events: first, we would exacerbate the ludic dimension of the iGEM competition to take part in the Brussels Games Festival; then, we would prepare a presentation to give to science classes in several High Schools in Brussels.
Biosafety
As mentioned earlier, the main concerns raised by Mighty Coli depend more on the protein that we chose to produce than on Mighty Coli in itself. However, Migthy Coli could compel an escaped recombinant bacterium to produce an industrial protein in the environment, when a bacterium without the Mighty Coli system would quickly degenerate to stop producing the protein of industrial interest. The risk seems thin, since such an overproducing bacterium would suffer from a clear competitive disadvantage in a wild environment. However it is not excluded that the plasmid containing the Mighty Coli system, since it benefits from the proprieties of the TA System, could manage to maintain itself anyway through Horizontal Gene transfer (HGT), at the expend of the wild bacteria it infects.
In the current state of our project, the protein production is boosted thanks to the TA System, but the plasmids are maintained through the usual system of antibiotic resistance, since the toxin and the antitoxin will be placed on different plasmids bearing different resistance genes. The system will thus decay quickly if the Mighty Coli bacteria wander in a wild environment, without any antibiotic. In the final version of our project (that is, if we have the time to go this far), the toxin gene will be inserted in the genomic DNA of the bacteria, preventing it to ever be lost, and compelling the bacteria to keep the plasmid bearing the genes of the antitoxin and the protein of interest. It will also prevent any reasonable chance of Horizontal Gene Transfer of the Mighty Coli system as a whole.
If, for one reason or another, the overproduction of a protein did not results in a competitive disadvantage, it would be wise to implement an build-in suicide sequence in the bacteria, to prevent it surviving outside the bioreactor. It can easily be done by the subordination of the antitoxin production to an inducible promoter that would be activated by a compound only present in the bioreactor.
In conclusion, Mighty Coli seems to be a safe and predictable system, whose biggest danger would be to be used to produce a dangerous protein. This latter problem has to be addressed on a case-by-case basis, by other institution than ours.
We have a safety page here too.
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- Université Libre de Bruxelles -
