Safety
Our project’s design has a large safety component since the possible negative effects of HGT (horizontal gene transfer) in the wild could be very detrimental to ecosystems.
Safety in the Environment
To dramatically decrease the chance for HGT we have implemented a “triple lock” system:
- Colicin E2 DNA Degradation Switch - Colicin E2 is a DNase which we have implemented into a “timed” kill switch which will degrade any DNA in the maxicell before maxicell’s metabolic timeframe end. This will significantly reduce the chance of HGT and the kill switch genes would be recoded as described in semantic containment.
- Semantic Containment - The recoding of genes on the instructor plasmid and the lack of chromosomal DNA prevents cells in the environment from being able to use any of the genes on the instructor plasmid therefore they cannot give a wild cell an advantage over others in the event of HGT from the maxicell to the wild cell. Any gene given to the instructor plasmid would be recoded for semantic containment.
- Triclosan Resistance - The spread of antibiotic resistance is a major problem, one that we didn’t want to add to. Instead of antibiotic resistance we use triclosan resistance in our chassis and in far lower amounts than found in toothpaste and industrial outflow. There are many benefits to using triclosan including increased environmental safety over antibiotics.
In addition to the work we have done to improve the chassis’ biosafety, maxicells are naturally safer in the environment due to their inability to reproduce which means they can’t accumulate mutations over generations and thus can’t evolve out of our control.
Lab Safety
The parts/gene products we have used have no effect on humans. We used only non-pathogenic well characterised lab strains for our experiments. Some protocells required the use of UV light (the UV maxicell protocol and viewing DNA in a polyacrylamide gel). All necessary precautions were taken to prevent harm (tinted goggles/ viewports and black boxes with automatic shut offs when opened). The necessary risk assessments were completed and approved for each stage and element of our project and experimental design. Wore personal protective equipment when necessary. Used fume hoods when working with chemicals which created hazardous fumes.
Contact EdiGEM18
Feel free to leave us a comment on social media!