Introduction

The Policy and Practices element of our project has asked how iGEM projects can grow from small lab studies into a commercial/industrial/medical product used by many people. An essential part of this research has been thinking about the safety of synthetic biology and specifically of the bioremediation technology we have developed, were it to be in widespread use.

The new risks associated with the growth of our project are broadly similar to those related to synthetic biology generally: the possibility of spread of antibiotic resistance from synthetic organisms into the natural environment, and the possible escape of synthetic organisms into the natural environment. Specific risks associated with our project include the risk to lab workers from working with chlorinated solvents (although this is relatively easy to manage). There may be potential for the abuse of the agarose bacteria-containing beads being developed by our team as this technology will allow bacteria to survive in hostile environments. However, we consider that the potential benefits from the application of our design far outweigh any possible risks.

Our bacteria are contained within agarose beads that will control the concentration of DCM which they are exposed to. Eventually these agarose beads will begin to degrade naturally over time, exposing the bacteria to a higher DCM concentration of up to 200 mM. The bacteria will die when the concentration rises above the level they can tolerate, thus we have a kill switch inherently integrated into our design. In addition, the agarose beads will be trapped by a filter within the DCMation container in order to prevent them from being disposed down the sink. Our product will include instructions explaining to users how the beads can be disposed of safely (for example by sterilising with boiling water before disposal).

Bacterial strains

Our team has been working with the following host strains. The table below indicates the risk group the organism belongs to - none of the organisms we worked with confer any risk to human health.
Oxford iGEM 2014

Risks to the safety and health of team members, or other people working in the lab:

The E.coli, DM4 and Pseudomonas strains used do not present any risk to humans (ACDP hazard group 1), as indicated in the table above, and none of the sequences expressed are under the control of mammalian promoters in order to avoid their expression in human cells. Good microbiological practice including the wearing of gloves, labcoats and eye protection will be followed at all times.

Risks to the safety and health of the general public (if any biological materials escaped from your lab) and risks to the environment:

We are not working with any pathogenic microorganisms or sequences that could introduce pathogenicity. The vectors we are using are designed for prokaryotes exclusively and none of the sequences expressed are under the control of mammalian promoters in order to avoid their expression in human cells. The above is also true regarding the risk to other animals and plants. The GMOs do not carry any additional risks for wild-type (unmodified) organisms.

Risks to security through malicious mis-use by individuals, groups, or countries and measures we are taking to reduce this risk:

Our work will not introduce or increase any pathogenicity or virulence of any of the microorganisms we are working with. The safety system of the Department ensures that only members of the Department have access to its facilities and that the microorganisms and genetic parts we are using will not leave the laboratory by any means. We decided to work with microorganisms that belong to risk group 1 exclusively. We will be wearing gloves, safety glasses and lab coats throughout our entire lab work and will carry out sterile techniques in order to avoid any contamination. We have arranged safe containment of the microorganisms we are working with so that these cannot leave the laboratory.

Features we have designed to minimise any risks:

Our bacteria are contained within agarose beads which will control the concentration of DCM which they are exposed to. Eventually these agarose beads will begin to degrade naturally over time, exposing the bacteria to a higher DCM concentration of up to 200 millimolar. The bacteria will die when the concentration rises above the level they can tolerate, thus we have a kill switch inherently integrated into our design. In addition, the agarose beads will be trapped by a filter within the DCMation container (pore size: 0.22 micrometres) in order to prevent them from being disposed down the sink. Instead of this happening, our product will include instructions explaining to users how the beads can be disposed of safely (for example by using virkon).