SAFETY
Overview
The FAFU team adhered to the principle of "safety first" during the whole process of the experiment. In this year's project, we screened human respiratory tract receptor protein (ACE2) with better binding ability to the novel coronavirus (SPIKE), and based on this experimental basis, built a sewage virus detection system based on the theory of sewage epidemiology.
Throughout the experiment, the tutor provided supervision and helped manage the risks we identified. Before the experiment, the team members will be given safety training and informed of possible risks and possible accidents. After ensuring that the experimenters are familiar with various operations and understand the risks, the experimenters can be very cautious and skilled in performing various operations. The whole experiment was conducted in accordance with the principles of self-safety, environmental safety and microbial safety.
Laboratory Safety
During the whole process of this experiment, our experiment was conducted in the Genome and Biotechnology Research Center, Strait College, Fujian Agriculture and Forestry University. In order to improve the efficiency and safety of the experiment, we made sure that the team members had a good understanding of the experiment
Master and familiar with the safety of procedures and reagents to ensure that we strictly follow the general guidelines for safety management of Fujian Agriculture and Forestry Laboratory during the experiment (FIG. 1).
Figure 1. General Guidelines for Laboratory safety management
As mentioned above, 75% ethanol is used for regular disinfection in our laboratory, which is well arranged, orderly and not crowded, and sufficient materials for disinfection and cleaning are ensured to properly cultivate aseptic operation awareness and experimental ability of laboratory personnel (FIG. 2A).
For waste recycling, we will use disinfectant to kill the remaining bacteria after the experiment and then pour it down the drain to ensure its sterility. For the molecular laboratory waste, we put it into hazardous waste bags and give it to professional companies for regular treatment. For the cell lab waste, we put it in a closed container and gave it to a specialized company for disposal (FIG. 2B).
In terms of operation, in order to avoid bacterial contamination during the cell experiment of the project, we are very strict with the operation. The operation is carried out in the laboratory specialized for yeast, and UV sterilization is usually carried out for at least 30 minutes before the operation (Figure 2C).
Figure 2. A laboratory disinfection and epidemic prevention supplies, B waste liquid collection bucket, C ultra clean table
Figure 2. D entry guard control system.
The access to the laboratory is also strictly restricted. According to the epidemic prevention and control situation in Fujian, the entry and exit of personnel are controlled. The entry and exit of personnel need to be verified by ID, and only the team members who are allowed to enter and trained can enter the laboratory (FIG. 2D).
Safety of experience
Figure 3. A researcher performs a bacterial manipulation
For some aseptic steps in the experiment, the experimenter had to perform them in an ultra-clean table, with all researchers wearing gloves, masks, and laboratory coats (FIG. 3). To use the instruments, the researchers followed a strict protocol.
In our project, we need to mutate ACE2 in human respiratory receptor cells to screen out mutants with stronger binding ability to COVID-19 spike protein receptor, which requires bacterial fluid. So the whole process, the experimenter must wear the lab coat, wear the goggles, mask, and use 75% alcohol before and after the experiment disinfection. Use ultraviolet light to disinfect the operating platform after operation. In addition, we submitted sign-in notices and received permission. None of this would violate China's biosecurity policy. During the whole process of the experiment, Teacher Qin Yuan and Teacher Cheng Yan gave us safe operation guidance to ensure the safety of the experiment.
The project safety
Carry out the thought of safety first. We focus not only on the safety of the lab, but also on the project. We submitted safety forms that included detailed information about our project. E. coli, as our chassis organism, only causes diarrhea. Experience with Escherichia coli TOP10 for gene cloning and expression. However, the above strains are usually used in laboratories, not everyday products. On the other hand, based on the results of the questionnaire survey, we believe that the safety of engineered bacteria is worrying. More than 50 percent were worried about its safety. Biological and physical methods were used to ensure the safety of the project. At the circuit level of the whole experiment, we designed a suicide system to ensure their safety, that is, after expressing our specific function, the cells will automatically die without posing an ecological threat.
Design considerations
In order to prevent the escape of our engineered bacteria into the environment, we specially implanted a blue light-coupled suicide system for the last engineered bacteria. When the blue light is exposed for a long time, the engineered bacteria will initiate the suicide program and express lysate proteins, leading to self-dissolution. At the same time, the toxic protein is not a nuisance to the environment because it acts in a specific part of the membrane of E. coli. In terms of hardware design, we have also fully considered the characteristic that the modified E. coli will die if it is exposed to blue light for a long time. In our program, the engineered bacteria that have been completed can be fully exposed to blue light. Ensure the safety of the whole device in use.
The "Do not publish policy" is the core rule of our laboratory. First, we don't allow genetically modified organisms to escape our LABS. At the same time, we haven't released any genetically modified organisms into the environment. Second, we don't have gene drive technology in our project. In addition, we did not conduct any animal experiments or human experiments. Finally, under the AMR Policy, we did not use any section containing AMR sequences from the WHO list.
