Overview
This year Peking iGEM Team is trying to develop a brand new method for the detection of pathogenic microorganism using the knowledge of synthetic biology. Here we are going to share our experience in safety control.
Safe Project Design
Choosing a non-pathogenic chassis
In our project, E.coli (lab strains that are non-pathogenic) was the only chassis when we performed the molecular cloning and protein expression. All the other experiments including protein purification and bioluminescence measurement were carried out in vitro.
Choosing parts that will not harm humans/animals/plants
Harmful parts are not allowed in our project. The parts in our project are most commonly used luciferase and dCas9 proteins, so none of our parts would raise any safety issue according to the current professional knowledge.
Substituting safer materials for dangerous materials in a proof-of-concept experiment
The original intention of our project is to develop a set of fast and convenient disease detectors, in order to prove the usefulness of our project, we did a series of experiments using absolutely safe genomic DNA of M. tuberculosis H37Rv as an example (the genomic DNA was prepared and offered by professional researchers in Chinese Academy of Sciences); we didn’t make any contact with the living or dead cells of this bacterium. Considering the safety issue, we did no more experiments using any materials from any other pathogenic bacteria.
Safe Lab Work
According to the requirements of iGEM policy, in our daily bench work we never performed any dangerous experiments or faced any unusual safety issues. Our bench work followed some basic regulations as below:
- Duplicating a key to the laboratory without permission is strictly prohibited.
- Experiment participants need to understand the experiment completely.
- Wear rubber gloves in all experimenters.
- Necessary steps should be performed in bio-safety cabinet.
- Fire, electric heaters, microwave oven should not be left while being used.
- Sterilize all liquid waste and solid waste containing living organism.
- Sterilize the lab using UV-light every week.
- The last person to leave the lab should make sure that water, electricity, gas, and air conditioner has been closed, and doors and windows has been locked before leaving.
For the proof-of principle test, we used absolutely safe genomic DNA isolated from B. subtilis and M. tuberculosis H37Rvas (Bio-safety Level 3). The genomic DNA of MTB H37Rv was prepared and offered by professional researchers in Chinese Academy of Sciences. What we did only was to use the genomic DNA for proof-of-principle test in Bio-safety Level 2 iGEM lab, which means that we never made any contact with the living or dead H37Rv bacterial cells.
Safe Shipment
As mentioned above, our DNA parts are absolutely safe because they encode the proteins such as dCas9, luciferase and their combinations. The DNA parts are tightly contained within PCR tubes as Partsregistry requires.