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Team:Leicester/Project
From 2013.igem.org
Go Leic-styRRRene!
Polystyrene is a multifaceted material - light, largely chemically and biologically inert, and easily shaped, but also a highly visible pollutant that locks up valuable hydrocarbons. In 2013 the Leicester iGEM team are retaining their focus on polystyrene but will diversify our approach. We have three streams involving recycling, re-using and re-purposing polystyrene.
Recycling – This stream involves building on the work of the 2012 team in environmental prospecting for genes involved in polystyrene degradation. Currently we have isolated organisms from environmentally exposed polystyrene, and are progressing in our aim of adapting the toluene degradation pathway of Pseudomonas species.
Re-using - Consumer 3D printers are now a reality and use a variety of thermoplastics (PS and ABS, for example). While the technology is constantly finding new uses, most involve using virgin plastics, which is not good for the environment. Recycled polystyrene can be used for 3D printing, but has an additional advantage as it is soluble in limonene (an environmentally friendly solvent), but ABS is not. Complex 3D printed shapes require removable support structures - one solution is to print the supports using PS and the object in ABS, with the PS being removed by limonene dissolution. We are adapting limonene biosynthesis biobricks developed in previous iGEM competitions to enable genetically engineered machine biological "finishing" of 3D printed objects.
Re-purposing (DNA!) - Expanded polystyrene (EPS) is a great insulator, used by the construction industry to make our homes warmer, using less energy. EPS insulation is required to be flame retardant, which is currently achieved by incorporating environmentally polluting halogenated hydrocarbons. Recently DNA has been shown to be an effective flame retardant, but is expensive to produce. We are building a genetically engineered machine with inducible endoreplication (over-replication of DNA). This should yield DNA cheap enough to burn and when added to EPS make it flame retardant and environmentally friendly.
