Team:Dundee/Safety
Safety
Safety
BactiFeed
As the goal of our project is to engineer a construct that will begin to produce bacteriocins while in the animal’s stomach and eventually lyse by the time the feed has reached the animals stomach. At first glance this proposal may suggest that cellular materials may be released to the environment or even available to be taken up by other bacteria colonizing the animal. In order to bypass this safety issue we decided to investigate the inclusion of an endonuclease gene in order to destroy all genetic material that would be released by the lysis of the cell. The inclusion of this gene would also prevent unnatural genetic material being released to the environment where it could have deleterious effects. Therefore, through this method we should avoid the release of any GMO material to the environment.
If this system was to fail and our construct was released into the environment and consumed by another animal this would not represent a huge problem as if the bacteria managed to survive the environmental conditions and make it to the neighbouring animals gut the construct would simply perform the same function in the target animal, killing the bacteria targeted by antibiotics.
The idea of coating our product with live bacterial cells may raise some safety issues however precautions were taken to avoid these issues as we decided to use the non-pathogenic species of E. coli MG1655. This species of E. coli is the can cause no harm to the livestock being fed the product or the farmer giving the feed to the livestock.
Toxic parts
To clone toxic parts strains of E. coli which are known to be non-pathogenic to humans were used, including MG1655, MC1061 and JM110, which are Hazard group 1 organisms, so while we were cloning toxins into E. coli, the resulting bacteria should only be toxic to the target strains of bacteria, and not to humans or animals. Our host laboratory worked with category 2 organisms and as such we followed all HSE health and safety regulations for category 2 laboratories.
Great care was taken to avoid contamination of other samples, as well as contact with skin. Normal PPE was worn including gloves, labcoat and safety glasses. 1% virkon was used to clean flasks which had contained bacterial material, before they were sterilised by autoclaving. No food or drink was consumed in the lab, hands were washed before entering or leaving the lab and bench tops were cleaned with 70% ethanol.
Risk assessment of chemicals used
Beta-mercapto-ethanol was used as a reducing agent for cysteine residues prior to SDS-PAGE experiments. Additionally to standard PPE, this substance was handled in a fume hood.
Acrylamide, HCl, sodium hydride and sodium cholate were used regularly, proper PPE was worn including gloves, labcoat and safety glasses to ensure no contact with skin occurred. All equipment was washed carefully after use.
The largest safety concerns were during the construction of the device. Laser cutting wood produces smoke that contains extremely fine particles. To prevent inhalation, the laser cutter is equipped with a fume extractor that exhausts out a window. Solder fumes are another concern as they can cause asthma given enough exposure. Again, a fume extractor was used to ensure the toxic fumes do not enter the lungs.
Operating the device is less of a concern. The gears under the deivce offer a minor pinch hazard but are difficult to access don’t have enough energy to damage skin. After long running times the power brick warms up. Potentially this could present a fire hazard so the it shouldn’t be left unattended for extended periods.
