Team:Amazonas-Brazil/Safety
Engineering organism with synthetic biology requires responsibility for the development of a safety project for our laboratory team, environment, and society.
Laboratory
Our project follows the iGEM’s Safety and Security Rules and every member of our team received extensive biosafety training to work safely and securely. We followed with great care Safety 1 lab procedures: Wearing appropriate gear (Lab coat, gloves, and goggles), washing and disinfecting our hands, working material, working spaces and equipment using available disinfectants (70% ethanol, HCl, etc.), carefully removing and properly discarding contamination and used Petri dishes. And we had two different workspaces for our team, one for Lab work and other for paperwork or related activities.
Every part and organism used in the project is part of the white-list of iGEM and we strongly compact to not release any sample of genetically modified organism or it’s products. None sample of genetically modified organism or its products were released in the environment or administered to humans during the execution of the project.
Real-world application - A therapy that is safe to humans
The greater goal of BeliEVE is to make the therapy of solid tumors with engineered organisms closer to reality. In light of this, every component of the project is designed to ensure safe treatment, from the choice of the chassis to parts used in the synthetic genetic circuit. In this process, we consulted and integrated the opinion of researches on Oncology, Immunology, Synthetic Biology and Development of Probiotics. Access our Integrated Human Practices to emerge in our journey to design BeliEVE
To perform the therapy, we’re using as a chassis the strain Escherichia coli Nissle 1917 which is widely used as a probiotic and can colonize solid tumors with a bigger specificity than other strains of E. coli and Salmonella in murine models1.
To reduce side effects and ensure that the medicine’s only expressed in the tumor and not in healthy tissues, we built a AND gate, which is composed by promoters induced by the major characteristics of the tumor microenvironment hypoxia and high concentrations of lactate
To directly deliver the payload in the tumor we are using the Secretion System Type 1 alpha-hemolysin is composed of the protein of interest fused to the signal sequence HlyA and an operon composed by the subunits HlyD, HlyB and TolC. This system is related to a pore-forming toxin by iGEM. This behavior is only present when the subunit HlyC - which is responsible to activate the hemolytic activity - is present. To avoid such behaviour our design does not include this protein.
References:
[1] Strizker, J. et al. (2007). Tumor specific colonization, tissue distribution, and gene induction by probiotic Escherichia coli Nissle 1917 live mice. International Journal of Microbiology, 297, 151-162.
[2] Thomas, S., Barry, I., Schmitt, L. (2014). The Type 1 secretion pathway- the hemolysin system and beyond. Biochimica et Byophysica Acta, 1843, 1629-1641.
