Poly (ethylene terephthalate) (PET) are highly versatile, their resistance to natural degradation presents a serious, growing risk to fauna and flora, particularly in marine environments.

PET, the strong plastic commonly used in bottles, takes hundreds of years to break down in the environment.

UK Researchers have determined the structure of a recently discovered enzyme that digests polyethylene terephthalate (PET), one of the most common plastics. This allowed them to engineer a mutant enzyme even better at breaking down PET.

In 2016 Researchers from Kyoto University isolated a new species of bacteria that uses PET plastics as its food source.  The new study, by University of Portsmouth researchers, builds on this work by isolating the enzyme responsible – PETase – and solving its crystal structure. The team could then work out how the enzyme interacts with plastic molecules and breaks them down. Using that information, they were able to improve the enzyme’s properties by making two changes in its active site.

To examine PETase's efficiency at the molecular level, the team used X-rays to generate an ultra-high-resolution 3D model of the enzyme, revealing an unprecedented glimpse of PETase's active site that enables it to grip and break down its PET target – and also, by chance, how that mechanism can be improved.

Source: soci.org, livescience.com,  https://doi.org/10.1073/pnas.1718804115