Safe Project Design

Choosing a non-pathogenic chassis

For our project, we chose to use chassis lab strains of  E. coli bacteria (DH5a and BL21 strains). As non-pathogenic to humans, these E. coli strains belong to Risk Group 1 and thus require only basic precautions. We chose these organisms for convenience reasons: their genomes are entirely sequenced (we knew that the sigma factor required for our transcription factor biosensor was in the bacteria), they are easy to grow and safe to handle.

Choosing parts that will not harm humans/animals/plants

We designed our project in a way that it should not include parts that could be harmful to humans, animals or plants. Our project involves a XylR transcription factor and a luciferase reporter and neither of these parts are known to have safety issues.

Biological Containment

Our project is designed for a use in everyday life which is why we were particularly aware of safety issues. The main risks we have identified can be linked to the use of biological elements. We are indeed planning to use genetically engineered bacteria, which implies an environmental dimension, given that those bacteria would be used in the field. This was our biggest challenge when we started the competition and in order to solve it we thought of a system to address this. We developed a containment method that will allow us to separate the bacteria from the environment. The container will be an enclosed device that allows air to be sampled and presented to the bacteria while preventing their accidental release (see Hardware). The first BioBrick tests were done in the laboratory under simulated environmental conditions. In the meantime, our Engineering team is developing a containment method similar to an airlock that would allow an efficient sampling of the air with no bacteria escaping the collection tube. However no field tests were made during the iGEM competition. Although our biggest challenge comes from biology, we also identified a mechanical risk in the drone. There is the possibility that the drone will have an accident. We thought of a security system for this event that will allow us to handle such accident without harm and pollution (see Hardware).