Throughout the project safety was always a priority when carrying out laboratory experiments. E. coli DH-alpha was the strain used for protein cloning and expression. This strain is not pathogenic and is the most widely used bacterial chassis among iGEM teams.
Due to the fact that we were handling level 1 biohazards materials, such as E.coli as our chassie, all members of the QGEM team that worked in the laboratory had to undergo safety training. This training specifically included information about handling level 1 biohazards, WHIMIS and general health and safety awareness training provided by our university. Graduate student advisors also carried out lab specific training outlining the following safety features:
When performing all laboratory experiments, we ensured each team member wore proper personal protective equipment including lab coats, gloves, long pants, safety glasses and closed toe shoes. We were also sure to work in proximity of our graduate advisors and PI.
If the PET repurposing system would be used in the future by industry or government, it would be important to incorporate a kill switch within the repurposing system. This would ensure that bacteria could only be contained with a bioreactor and thus prevent them from escaping into the environment and unnecessary digest plastics that they weren’t supposed to. A possible method for doing this would be by incorporating codons for non-canonical amino acids within each enzyme, thus making the enzymes functional only when the growth media contains the specific amino acid. If these bacteria would be accidentally released into the environment any proteins that they would produce for the repurposing system would not be functional, thus preventing any unwanted PET degradation. Also, for future applications for this technology, possible processing methods may also be needed for the isolation and refinement of the produced PHB.