Tailoring enzymes for polyester-plastic depolymerization

The accumulation of plastic wastes poses a severe and growing environmental threat, driving the need for sustainable recycling solutions. Enzymatic depolymerization has emerged as a promising green alternative for plastic waste treatment and valorization. To enhance its practical application, protein engineering has been employed to optimize plastic-degrading enzymes. This review summarizes recent advances in engineering enzymes for the depolymerization of various plastics, including polyethylene terephthalate (PET), polyurethane (PU), polylactic acid (PLA), and polybutylene adipate terephthalate (PBAT), with a focus on improvements in thermal stability, catalytic efficiency, and recombinant protein expression. Key future directions for the modification of polyester plastic-degrading enzymes have also been identified. These developments are crucial for designing efficient and industrially viable biocatalysts to tackle the plastic pollution crisis.