Project
Biosafety is an important issue facing synthetic biology. Concerns surrounding synthetic organisms escaping into the environment has prompted the development of novel methods of bio-containment. Despite this, kill switches - inducible genetic devices that cause cell death - are poorly categorised in the standard registry of genetic parts. There is a distinct lack of quantitative data which prevents them being used with confidence.
Many iGEM projects that focus on bioremediation or require an organism to be released from the lab use kill switches to address concerns about the effect of GMOs on the environment. Our project seeks to investigate the effectiveness of different types of kill switch.We want to quantify their robustness after several generations and compare the stability of these devices when integrated into the genome or carried on a plasmid. We are testing three types of kill switch: a chemical kill switch using the fluorescent proteins KillerOrange and KillerRed, an enzymatic kill switch that lyses the cell on production and a DNAse kill switch that targets DNA disruption.
Human Practices
Our Human Practices is centred around improving public engagement and tackling the lack of education of synthetic biology in the UK and overseas. In particular we are targeting education at a secondary school and university level, focusing on the interdisciplinary nature of the subject and assessing diversity. We want to highlight the benefits and potential applications of this new scientific field, as well as trying to uncover the reasons why synthetic biology doesn’t get as much positive attention as it should have.
We are working hard to introduce a new synthetic biology module to The University of Exeter’s curriculum, which will be available to students as soon as September 2017. For school children we have created a board game, BioMech, which educates students in key synthetic biology concepts in an easy to understand and engaging way. Furthermore, we have visited school and fairs, giving talks and running workshops where we aim to give children an introduction to what synthetic biology is and how it already affects their lives for the better.
By interviewing researchers, academics and other professionals within the scientific community and presenting their opinions in a fun and educational way, we hope to have made synthetic biology a more attractive discipline to the general public.
Team
We are Exeter University’s 2016 iGEM team made up of first,
second and third year students from a wide variety of disciplines. We want
to address the question ‘what makes something a kill switch?’ as well as
helping to distinguish synthetic biology as a positive tool that can be
used to combat key problems from multiple scientific fields.
Modelling
Our team has decided to models for our 3 different types of kill
switch:
- KillerRed and KillerOrange models: These homologues of GFP produce
high levels of ROS, which lyse the cell and also damage the DNA.
We have modelled the death of cells that express KillerRed or KillerOrange
over time.
- Lysozyme C model: Lysozyme is a common enzyme used in laboratories and
the Gallus gallus form is basis of our enzymatic kill switch.
It is bacteriolytic when transported into the periplasm of gram
negative bacteria, hydrolysing the glycosidic bond connecting
N-acetylmuramic acid and N-acetylglucosamine. We have modelled
the time it takes for lysozyme c to break down the peptidoglycan
which makes up the cell wall.
- DNAse 1 model: DNase 1 is an endonuclease that non-specifically
cleaves DNA. We are modelling the time it takes this enzyme
to degrade DNA and kill the cell.
