Mechanistic-based Design of Efficient PET Hydrolases
Authors
Wei, R., von Haugwitz, G., Pfaff, L., Mican, J., Badenhorst, C. P. S., Liu, W., Weber, G., Austin, H. P., Bednar, D., Damborsky, J., Bornscheuer, U. T.
Source
ACS CATALYSIS 12: 3382-3396 (2022)
Abstract
Polyethylene terephthalate (PET) is the most widespread synthetic polyester, having been utilized as textile fibers and packaging materials for beverages and food, contributing considerably to the global solid waste stream and environmental plastic pollution. While enzymatic PET recycling and upcycling have recently emerged as viable disposal methods for a circular plastic economy, only a handful of benchmark enzymes have been thoroughly described and subjected to protein engineering for improved properties over the last 16 years. By analyzing the specific material properties of PET and the reaction mechanisms in the context of a heterogeneous biocatalysis, this Perspective identified several limitations in current enzymatic PET degradation approaches. Inefficient enzyme-substrate interactions, limited thermostability and low catalytic efficiency at elevated reaction temperatures, and inhibition caused by oligomeric degradation intermediates are still hampering industrial applications that require high catalytic efficiency. Successful protein engineering research using novel experimental and computational approaches has been published extensively in recent years in this thriving research field and are summarized and discussed in detail here. The acquired knowledge and experience will be applied in a near future to address plastic waste contributed by other mass-produced polymer types (e.g., polyamides, polyurethanes) that are also prime candidate plastics worthy of recycling by a biotechnological disposal option.