Contents
PEST Analysis
As part of our gold medal requirements for human practices, we have decided to use an analytical framework largely used within social sciences, the PEST analysis. PEST (political, economic, social and technological) describes a framework of macro-environmental factors used in the environmental scanning component of social sciences. We have decided to adapt it to our iGEM project in order to examine in a more structured way the macro-environmental factors that will have an impact on our project. This analysis is used to assess these four external factors in relation to our situation. Even though PEST is usually used for business management and organisational purposes, we recognised that such an approach would have represented a useful tool for integration of social science into our synthetic biology project. As human practices tend to emphasise the importance that factors outside of the laboratory affect our work, and how our work affects the world outside, a PEST analysis has helped us determine the weight that each one of those factors will have on the success of our project.
Political
In terms of political factors affecting our project, we have incorporated public policy as well as legal considerations in order to have a comprehensive political framework. This year we have considered legislation regarding both the use of GMO biosensors within the European Union, as well as regulations on food hygiene standards and general food safety law. In addition, we have devolved particular interest to recent political changes that might affect our project; specifically, we have considered potential implications that Brexit will have on future national legislation. In terms of GMO legislation, we have found out that the central issue is the use of live genetically modified organisms outside a contained and properly registered laboratory. This is covered in the EU by 2009/41/EC for contained use and 2001/18/EC for deliberate release into the environment, or in the UK, the Genetically Modified Organisms (Contained Use) Regulations 2014. In terms of food safety law and food hygiene legislation, we have considered several policies that the UK has been adopting in order to ensure that farming, food safety management procedures, and food hygiene regulations are being kept at high standards. Some of these policies include the Regulation (EC) 178/2002, which set out the general principles and requirements of food law in the EU; and EU Regulation 882/2004 on official controls for feed and food law (and animal health and animal welfare) sets out the approach that competent authorities of member states must adopt for official controls. Since most of the legislation we have considered is EU-derived, we believed it would be useful to analyse the potential impacts that an upcoming exit of the UK from the EU would cause to the future of such policies. For this reason, we have dedicated particular attention to the recent political turmoil that has been characterised by uncertainty on the future of national legislation. A detailed policy brief can be found here.
Economic
In terms of economic impacts of our project, our main priority is to create a biosensor that will be economically advantageous compared to current costs that laboratories have to face when testing chicken for campylobacter. When researching current data on economic costs associated with this, we asked Scotland's Rural College about current procedures used for testing chicken for campylobacter. At present the procedure includes swabbing the birds, sending the swab to the lab and get the results up to a week later. We were told that an instant result would have been most helpful. In order to establish the economic costs associated with such a procedure, we analysed figures that determined the current costs, technologists’ time, and time to a positive and negative result using conventional culture methods. The figures were provided by the Department of Pathology, University of Texas Southwestern Medical Center, that recorded the costs per stool culture for media and reagents. According to the statistics, average costs for media and reagents for cultures were as follows: No potential pathogens, $5.74 (£4.28) (n=74); negative cultures with additional workup, $7.27 (£5.43) (n=127); and positive cultures, $9.33 (£6.96) (n=5). Shigella sonnei, Campylobacter species and Salmonella species were the bacterial pathogens that were recovered in the 5 positive cultures. To evaluate the technologists’ time, 5 different technologists recorded the time that they spent on stool workups. The average technologist time required to complete a single final culture was approximately 8 minutes (range of 1-15 minutes). Using an average cost of $27 (£20.16) per hour for technologists’ labour and benefits and 8 minutes of time per culture, the labour cost per culture was $3.60 (£2.69). Including media, reagents and labour, the average cost to detect a single positive culture was $427 (£318.76). While negative cultures with no potential pathogens were reported at 48 hours, positive cultures required 72 to 96 hours to finalise. Our aim is to reduce the economic impact that comes with swabbing and using laboratory facilities, by providing a more affordable alternative that saves users both time and money. On a macro-scale, being the UK economy enormously affected by campylobacter related infections, our biosensor will serve as a tool to benefit macro economic issues.
Social
Our targeted stakeholders can be divided into three categories; farms, industrial kitchens, and private customers at home. As a consequence, the biosensor will be used to detect campylobacter at different stages of the process, even though it will serve the same purpose. The social factor was particularly important to us as human health is the main reason behind our research project. We wanted to find a quick and easy solution for an issue that negatively affects it, since campylobacter related infections represent an enormous issue for human health in the UK as well as in the rest of the world, but they are so easily preventable that the amount of infections could ideally drop to zero with education and prevention.
Technological
The aim of our project was to make a functioning genetically engineered biosensor. The device consists of 3 elements: • Swab attached to a syringe containing 1% acetic acid • Processing plate for preparing the sample for detection • Heating Element using a separate electronic circuit A swab of the area for testing is taken, and then inserted into the input section of the processing plate. The syringe is the pushed slowly to detach the sample and pass it through the device. To prepare the sample, it is taken through a series of stages which will release the sugar xylulose from the capsule of any campylobacter bacteria present. These being: • Heating the acid and sample to 100 Degrees Celsius (which detaches xylulose) • Neutralising the acid using a Tris-Acetate buffer (making the solution innocuous to the E. coli) • Testing the pH using litmus paper • Mixing with glucose (ensuring the E. coli does not metabolise the xylulose) After the stages mentioned above, the sample is ready to be delivered to the detection chamber. Here, a strip of filter paper that had been pre-prepared with a hydrogel coating that contained our genetically modified E. coli cells is inserted into the chamber which allows the liquid sample to diffuse into the cells. The detection chamber, along with the rest of the device, is transparent, allowing the user to observe any colour changes should xylulose be present in the sample.
Aims
- Aim 1
- Sub-aim 1
- Sub-aim 2
- Aim 2
- Sub-aim 1
- Sub-aim 2
Materials and Methods
Condition set up
Sample preparation
- 1
- 2
- 3
Results and Discussion
Outlook
References
- ↑ Kiliç, A. O., Pavlova, S. I., Ma, W. G. & Tao, L. 1996. Analysis of Lactobacillus phages and bacteriocins in American dairy products and characterization of a phage isolated from yogurt. Appl Environ Microbiol, 62, 2111-6.
