IMPEDE · Integrating micro electron diffraction into bioplastic degrading enzyme development

Plastic pollution is a critical global challenge, and bio-based biodegradable plastics like polylactic acid (PLA) are increasingly used to replace fossil-derived materials. However, PLA degrades slowly under industrial composting conditions, limiting its environmental impact. Highly efficient, thermostable plastic-degrading enzymes (PDEs) could enable faster PLA breakdown and support more scalable waste management solutions.To date, enzyme engineering for plastic degradation has relied on X-ray crystallography to guide design, but this approach struggles with sub-micron crystals, insoluble polymer substrates, and limited hydrogen contrast, particularly for mapping polymer–enzyme interactions. As a result, no true substrate-bound PDE structures are available, restricting mechanistic understanding and slowing industrial enzyme development.This project pioneers the use of electron diffraction (microED) in PDE research. MicroED enables high-resolution structures from nanocrystals, offers stronger hydrogen contrast, and facilitates more effective ligand soaking, making it uniquely suited to resolve substrate-bound enzyme complexes.IMPEDE will: (1) produce, screen, and engineer PLA-degrading enzymes from underexplored families; (2) solve new PDE structures using MicroED; and (3) obtain the first substrate-bound PDE structures with true plastic ligands. Engineered enzymes will be assessed for improved activity and thermostability under industrially relevant conditions.Expected outcomes include novel industrial biocatalysts for PLA and blends, high-value structural data for protein design, and a robust MicroED workflow to accelerate future enzyme discovery. Environmental benefits include faster bioplastic degradation, reduced landfill and marine accumulation, and alignment with EU 2050 climate neutrality goals. From an industrial perspective, these enzymes could drive adoption of bioplastics by improving end-of-life processing economics and reliability.