Engineering enzymes to help solve the planet’s plastic problem

Researchers from the Manchester Institute of Biotechnology (MIB) have developed a new enzyme engineering platform to improve plastic degrading enzymes through directed evolution. To illustrate the utility of their platform, they have engineered an enzyme that can successfully degrade poly(ethylene) terephthalate (PET), the plastic commonly used in plastic bottles. In recent years, the enzymatic recycling of plastics has emerged as an attractive and environmentally friendly strategy to help alleviate the problems associated with plastic waste. Although there are a number of existing methods for recycling plastics, enzymes could potentially offer a more cost-effective and energy efficient alternative. In addition, they could be used to selectively breakdown specific components of mixed plastic waste streams that are currently difficult to recycle using existing technologies. Although promising as a technology, there are considerable hurdles that need to be overcome for enzymatic plastic recycling to be used widely on a commercial scale. One challenge, for instance, is that natural enzymes with the ability to break down plastics typically are less effective and are unstable under the conditions needed for an industrial-scale process.