Development of a Thermophilic Microbial Platform for Consolidated Bioprocessing of PET Waste

Abstract

The accumulation of polyethylene terephthalate (PET) waste presents a growing environmental concern. Biological PET upcycling, which couples enzymatic depolymerization with microbial conversion of monomers into value-added products, offers a sustainable alternative to traditional recycling. However, most engineered hosts operate at mesophilic temperatures, while efficient PET depolymerization requires elevated temperatures, creating a bottleneck for process integration. Here, we report the engineering of a thermophilic bacterium capable of performing both PET degradation and monomer assimilation. Thermostable PET hydrolases were expressed, and central metabolic pathways were reprogrammed to enable efficient uptake and conversion of its monomers. This design enables consolidated bioprocessing of PET under thermophilic conditions. Our results will demonstrate the feasibility of high-temperature microbial PET valorization and provide a foundation for scalable, one-pot plastic waste bioconversion systems.