Special concerns with biofilm safety

Biofilm, although very useful in our project, can also be dangerous when introduced to the nature. We realize that biofilm is linked to numerous issues such as diseases, biocorrosions, food contaminations and anti-biotic resistance. However, our biofilm itself is unlikely to be harmful since neither JM109 nor DH5α is pathogenic nor very resistent to mechanical sheer. They are the most widely used strains of e.coli in synthetic biology labs. In addition, the biofilm formed by these two species disperse automatically if deprived of nutrient. Also the expression of AI2 is induced by arabinose, which is present only in a few environments. Thus in general our biofilm is unable to produce a severe biosafety issue.

Yet if AI2 is released in the nature, it can induce the biofilm formation of other species. We have chosen AI2 over other factors that induce biofilm because AI2 promote pili and pili movement motor synthesis as well as biofilm formation. Since cell movement is also promoted its effect is not permanent. But more important than that, we have taken special attention in sterilizing all containers as well as the culturing media with bleach and autoclave, thus reducing its leak to the environment to the minimum. All researchers involved in biofilm formation have been educated about the consequences.

Researcher safety

Our researchers mainly face regular bio-safety challenges in a molecular microbiology lab, such as risks staining DNA agarose gel with EB, extracting RNA from organisms with TRIZOL, and manipulating with DEPC treated water, etc. Any researchers conducting such experiment are instructed about the right method both by printed protocols and BIG BROTHER in the lab (XD). After the training, we must pass an on-line test about the lab safety, standard experiment procedure and lab waste treatment. During any experiments, necessary individual protections such as gloves and white robes are always required. Also, the public safety of the lab is guaranteed by the strict registering protocols on the operation of any apparatus. In order to make sure all the requirements above were followed well by the researchers and to get prepared for any emergency, our lab (also is the open bio-lab of the college) set up 24hr*7 camera system in the room.

Public safety

First we picked DH5α and JM109 as the two strains to manipulate in our research. These are two non-pathogenic E. coli strain and do not pose problems to the public health. The bio-parts we utilized are all security ensured, coding for florescence protein, cellulose degradation enzymes and metal ion binding proteins. Although bio-film formation is closely related to pathogenicity, our experiment enhances bio-film formation only by changing the external environment factors instead of modifying the inherited nature of the bacteria. This is an important measure to assure that the bacteria do not acquire previously non-existing pathogenic capacity.

Environment safety

The experiments conducted in our lab are with intensive concern of environmental impact. No media containing engineered germs go into the sewer before sterilization. Besides, all the utensil contacted with the engineered bacteria must first undergo sterilization then be washed. During our research we have used antibiotic resistant plasmids, including chloramphenicol, kanamycin, ampicillin. Though risks of the practices exist, we believe that it's possible for us to use them safely with the mature protocols and techniques. For the toxic and hazardous chemicals, they are collected and treated properly. The acid and basic chemicals are neutralized and pour into the swer.

Biobrick safety

Our biobricks includes two new promoters responded to oxygen concentration, hence the regulation of the devices would not involve potentially bio-hazard chemicals. Also as partially described above, our parts express proteins aiming at binding of metal ions, degradation of cellulose, and the localization by fluorescent proteins. All of these products are not bio-hazard, and the expression is under fine control.

Biosafety provisions

Our experiment is designed and carried out following the standards of national biosafety office, especially the 《Safety Administration Regulation on Genetic Engineering》 (Only the chinese version is available online),as well as the laboratory regulations of our university, the college of life sciences, and the biology lab center.