PET, or polyethylene terephthalate, is one of the most widely used plastics in the world and is commonly found in reusable drink bottles. However, once a PET product reaches the end of its lifecycle, it can be difficult to dispose of without harming the environment. To combat this, researchers from Leipzig University have been working on an enzyme that can break down PET in an environmentally friendly way. In a recent publication in Nature Communications, the researchers revealed their findings on how the enzyme works and increased its efficiency. This research builds on previous work from almost a decade ago, when biotechnological enzyme research in Leipzig first established the determination of the first structure of a PET-degrading enzyme.
To understand how PHL7 achieves such efficient reaction acceleration, Christian Sonnendecker collaborated with other experts who used computer simulations and quantum chemical calculations to analyze the enzyme’s reaction mechanism and the role of individual amino acids in binding to PET. While these predictions were useful, experimental results ultimately determined the success of enzyme improvements. The team was able to make changes through genetic engineering that increased the enzyme’s activity and stability, without causing it to bind too strongly to the substrate. The proposed sliding mechanism, which uses a binding channel to bring the substrate to the active center, demonstrated that less can sometimes be more effective.
Christian Sonnendecker, an early career researcher from the Institute of Analytical Chemistry at Leipzig University, plans to use nuclear resonance spectroscopy to investigate how the enzyme binds to the polymer substrate in future interdisciplinary research. The team is already working on the third generation of the enzyme, incorporating artificial intelligence and new screening methods to design enzymes more efficiently. However, Sonnendecker ultimately sees the future in bioplastics, which are based on renewable raw materials and more easily biodegradable than petroleum-based plastics. He hopes to establish a technological alternative to the fossil fuel-dependent plastics industry and create artificial CO2 storage through his work, ultimately leading to a “green future with a view to plant-based raw materials.
Source: Leipzig University