Team:UCLouvain/HP/Silver
The safety of our project was always in our mind while working on it since the primarily goal of the badge is to be used outside of the lab. We decided to design it in a way that prevent our modified bacteria from escaping into the environment. The badge includes a ring filled with bleach which is mixed with the bacteria contained into the capsule once it has been used. The bleach will rapidly kill the bacteria and ensure that no one of them can escape.
Although it ensures that no bacteria will leave the badge alive when discarding it, another biosafety mechanism could be used in case of a capsule leak or even a break upon a hit. One way to prevent this kind of escape road is the introduction of a kill switch inside our bacteria. Several kill switches have been designed and registered as biobricks by multiple iGEM team during the past years. The implementation of one of them would add another barrier and lower even more the risk of our bacteria escaping.
We decided to make our badge in a way that limit its impact on the environment. The badge is mostly made out of Polylactic Acid, which is a biodegradable polymer. The badge is also fully reusable. The support can be kept by the user and the two others parts can be easily cleaned and replenish. The badge is also fully manufacturable using only 3D printers and polymers that are easily accessible.
Using the iGEM’s biobricks, we construct a plasmid containing a gene coding for a RFP. Arabinose activates this gene, thanks to its pBAD promoter.
On the other hand, we knocked out (KO) a gene required for tyrosine synthesis in E. coli, TyrA. A medium containing photo-caged tyrosine (Ortho Nitro Benzyl-Tyrosine) is used to grow the bacteria: this special tyrosine is sensitive to UV’s, and will be only available for our KO E. coli once uncaged.
learn moreComS is a small peptide imported into the cytoplasm by the cell. Interacting with ComR, it will form a complex, that acts as a gene activator.
ComS contains some tyrosine. Thanks to a collaboration with…, we synthetize ComS using the photo-caged Tyrosine instead of Tyrosine. This new ComS can’t interact with ComR, unless its Tyrosine have been uncaged by UV’s.
The complex of ComR/ComS will simply activate a RFP gene, creating as previously a system responding to UV’s.
learn more- Belgian Cancer Registry, n.d. Belgian Cancer Registry — Tableaux sur base annuelle [WWW Document]. URL http://www.kankerregister.org/Statistiques_tableaux%20annuelle (accessed 10.24.17).
- CHU de Liège, n.d. Le mélanome [WWW Document]. URL http://www.chu.ulg.ac.be/jcms/c_8187263/le-melanome (accessed 10.24.17).
- World Health Organization, n.d. WHO | Skin cancers [WWW Document]. WHO. URL http://www.who.int/uv/faq/skincancer/en/ (accessed 10.24.17).
