Safety

Overview

Squirrel-Guangzhou recognizes the importance of safety in the entire iGEM project. Therefore, we have divided safety into two parts: biosafety and laboratory safety. In terms of biosafety, we have implemented a light-controlled suicide system to ensure biological safety. At the same time, we are aware of the inherent risks of working in laboratory facilities and are committed to taking all necessary precautions to prevent harm to individuals or the environment. To this end, we have implemented laboratory safety measures.

Biosafety

To prevent bacterial leakage, we have implemented strict engineered eradication measures—a light sterilization system. We selected a light-activated suicide switch based on the YF1-Fix blue light-sensitive system, ensuring that E. coli can only survive under blue light conditions and will be killed in darkness. This system, BBa_K3034012, consists of a blue light-sensitive promoter switch (BBa_K592004, BBa_K592005, and BBa_K2277233) and the lysin gene Lysep3-D8 (BBa_K3034004). The lysin gene is a composite protein that can lyse bacteria both inside and outside the cell, theoretically exhibiting stronger bacterial lysis effects. We have completed both the plasmid and experimental design, but due to time constraints, the experimental validation has not yet been completed.

Fig. 1 The three plasmid diagrams in represent the suicide gene system and its control experiments. To verify the function of the lysozyme and the light-inducible promoter, we designed three plasmid combinations: EL222-Pblind + RelE, T7 + RelE, and EL222-Pblind + mKate, which are located in the upper left, upper right, and lower sections.

Lab Safety

Chassis

The chassis we used are E.coli DH5a and E.coli Mach1-T1, which all belong to RISK GROUP 1, meaning they are low risk for humans and the environment.

Part

Our parts are all taken from RISK GROUP 1 and RISK GROUP 2 organisms. The RISK GROUP 1 organisms are not safe to cause diseases in healthy adults. Although the RISK GROUP 2 organisms may cause diseases in humans, the parts we extracted were all synthesized from the company, without any risk of pathogens.

Disposal

In our laboratory, we have designated containers for solid waste, waste liquids, and sharps, all of which are managed and collected by Jet Biofil. We are required to fill out labels, clearly indicating the "date, lab location, and type of waste," and attach them to the waste bags or liquid waste containers for centralized collection and disposal by Jet Biofil.

Additionally, to prevent environmental contamination, we collect all bacterial culture media and sterilize them before disposal. To maintain laboratory safety and cleanliness, we conduct regular cleaning, sterilization, and disinfection on a daily basis. The clean bench is sterilized with UV light before use.

Training

Our team members participated in two laboratory safety training sessions.

First Training

The first training was an online course conducted by our Secondary PI, Riva Yan, who explained laboratory safety, including the Safety Form, daily laboratory management regulations, safe usage of water, electricity, fire, and gas in the laboratory, safe handling of chemical reagents, hazards and management of microorganisms, safe usage of radioactive materials, the hazards and protection against UV radiation, and waste management.

Safety Training Image 1
Safety Training Image 2
Fig. 2 Online Laboratory Safety Training.

Second Training

The second training was an in-person session held in the laboratory, where our instructor, Rong, provided hands-on safety instruction, covering the use and precautions of basic laboratory equipment, the operation and precautions of the clean bench, waste management, daily laboratory hygiene and safety management, and the use of emergency escape routes.

Fig. 3 Offline Laboratory Safety Training.

Operation

Our laboratory operations strictly adhere to the safety regulations of the Jet Biofil laboratory (PDF file below). Additionally, we have established the following daily laboratory rules:

  1. Lab coats must be worn at all times while working in the laboratory.
  2. When handling volatile toxic reagents, operations must be conducted in a fume hood.
  3. All reagents have designated storage locations and must be returned after use.
  4. All chemicals and reagents must have clean, clearly marked labels, including the name, concentration, and specifications.
  5. After completing work, all laboratory surfaces must be disinfected daily.
  6. Eating, drinking, and smoking are prohibited in the laboratory.
  7. Mouth pipetting is strictly forbidden. Lab-provided pipettes, syringes, and pipettors must always be used.
  8. Contaminated glassware, plasticware, and discarded petri dishes must be placed in containers designated by the supervising coach.

Safety Form

Final Safety Form: Link to Safety Form