Triple Helix

The Triple Helix is a global forum for science in society run by students at over 25 of the world's leading universities. Their journal 'Science in Society' is printed termly and Cambridge iGEM was asked to provide a short article for the Michaelmas 2012 (autumn) edition. Below is a copy of the article submitted:

The iGEM (international genetically engineered machines) competition began at MIT in 2003 and the Cambridge team has competed every year since 2005 when it first became international, winning the globally in 2009. Students work in teams over the summer and then present their research at international conferences; the university team will be going to Amsterdam for this purpose in early October. Though the competition is primarily for undergraduates, many teams benefit from graduate mentors who are often themselves previous iGEMers, who provide invaluable advice and guidance over the course of the project.

Central to the competition is the teams’ production and use of biobricks (standard biological parts) though synthetic biology. When put together the biobricks can be constructed into ‘devices’ within bacterial systems which can do anything from making E.coli smell of bananas to glow bright red in the presence of arsenic.

The team’s project this year has been focussed on producing a standardised output with instrumentation for biosensor experiments, such as are often used in within the iGEM competition. To do this we have created ratiometric light emitting constructs using fluorescent proteins and luciferases - bioluminescent proteins found in fireflies and some bacteria.

Many people are familiar with the idea of coupling light emmitance to the production of a substance within cells to estimate its concentration, but this system has inherent problems. Does a low reading indicate low production in a lot of cells or that most of the cells are dead and very high production exists among the survivors?

The ratiometric construct helps by using two colours. One colour is produced constantly while the cell is undergoing protein synthesis, the other induced under set circumstances. Taking the ratio of these outputs allows for calculations of production per cell. Through quantification experiments, plotting output per cell against known concentrations, it is possible to characterise biological parts – effectively, producing a data sheet.

Students must be in the intermediate years of their first degree to compete in the undergraduate division of iGEM and this year’s team features 6 biologists and 2 engineers. Many students choose to spend these summers on laboratory research placements or scientific internships and opportunities like these are intensely important to the students who take them, providing valuable laboratory experience and extremely interesting summers.

The great advantage of the iGEM competition however is that, while supervised (primarily by Dr Jim Haseloff); it is the students’ project from their interests. And though it can occasionally feel like being thrown in at the deep end – once you start climbing the rather steep learning curve, it’s more than worth it.