Overview
To ensure the highest safety standards throughout our project, we implemented a multi-layered biosafety strategy. Our engineered chassis, Yarrowia lipolytica and Escherichia coli are a BSL-1 organism approved by iGEM, and all experiments were conducted under strict containment protocols. Team members received certified safety training and adhered to standardized lab practices. Project-specific risks were mitigated through design features such as kill switches and environmental containment systems. All procedures were reviewed and supervised by our institutional biosafety committee, and no incidents occurred during our wet lab work. This comprehensive approach ensured full compliance with iGEM safety policies and maintained a zero-risk environment throughout our research.
Biosafety and Safety Design
Our engineered strains, Yarrowia lipolytica and Escherichia coli are well-characterized organisms listed on the iGEM White List and classified as a Biosafety Level 1 (BSL-1) chassis. From the design stage, we prioritized the use of non-toxic genetic parts and safe metabolic pathways to minimize any potential risks to human health and the environment.
To prevent uncontrolled proliferation or release, we designed and utilized biocontainment mechanisms, including inducible kill switches and auxotrophy-based safeguards.
We designed a intriguing suicide system which allowed the yeast to survive under room light but die under sunlight or single blue light.Comparing the difference of room light and sunlight,we discovered a slightly but important point that the modern lamps,LED for example,doesn’t produce far-red light. Hsp82 and Hsc82 have been verified as the significant protein for maintaining the structure of cell membrance of yeasts.When the kill switch is triggered,the Crispr will recognize the homologous sequence of Hsc82 and Hsp82 genes by the sgRNA and knock them down which can lead to the death of the yeasts.
Daily Laboratory Safety Practices
All team members completed certified online safety training, including modules on aseptic techniques, pipetting, chemical handling, and biological containment. Only after passing the assessments were they allowed access to the lab.
Standard BSL-1 protocols were strictly followed: lab coats, gloves, goggles, and sterile techniques were used at all times.
The laboratory is equipped with safety infrastructure, including eye-wash stations, fire extinguishers, autoclaves, biosafety cabinets, and chemical waste disposal systems.
All biological waste (including liquid cultures and contaminated disposables) was autoclaved or chemically inactivated before disposal, ensuring no live organisms were released into the environment.
Project-Specific Risk Mitigation
Some experimental steps involved the use of intermediate metabolites with potential cytotoxicity or volatility. These were handled exclusively in fume hoods with appropriate PPE and documented risk assessments.
All new constructs, strain modifications, or high-risk procedures were subject to an internal biosafety review process and required approval from both our team’s safety officer and the institutional biosafety committee.
Prior to any scale-up experiments or non-standard cultivation, we conducted rigorous safety evaluations to ensure that the engineered Y. lipolytica strains remained stable and non-invasive under all tested conditions.
Environmental Containment & Application Safety
In alignment with the iGEM “Do Not Release” policy, no live genetically modified organisms (GMOs) were released into the environment at any point during the project.
All device outputs and bioreactor waste were routed through multi-layer decontamination steps, including thermal sterilization, UV irradiation, and microfiltration.
Our hardware is equipped with a blue light emitter at the top to activate the suicide switch in the bacterial strain, preventing bacterial leakage.
The hardware is constructed with tight seals and threads, while sterile-grade membranes are installed at both the inlet and outlet to prevent leakage.
Training, Oversight & Emergency Response
All wet lab members participated in in-person biosafety workshops and emergency drill sessions (e.g., for spills, accidental exposure, or equipment failure).
A designated Safety Officer was responsible for maintaining a weekly inspection log covering PPE compliance, waste management, equipment functionality, and overall lab hygiene.
Any unexpected incidents or near misses were immediately reported, contained, and logged. An internal review was conducted to update protocols and prevent recurrence.