| Abstract | Plastics are indispensable materials due to their versatility and durability; however, these same properties contribute to their persistence in the environment and growing waste management challenges. Current end-of-life strategies—landfilling, incineration, and mechanical recycling—remain insufficient for addressing the accumulation of recalcitrant polymers. In particular, poly(ethylene terephthalate) (PET) resists degradation and fragments into microplastics, posing significant ecological and human health risks. Within the context of Engineering Biology solutions, biodegradation using recombinant strains could be a promising alternative for PET degradation. We are exploring a thermophilic biocatalytic strategy for PET degradation through the engineering of Geobacillus spp. to express a fused PETase–MHETase enzyme derived from Ideonella sakaiensis. Operating at elevated temperatures near PET’s glass transition (~70 °C) is expected to enhance polymer chain mobility and enzymatic accessibility, thereby improving hydrolysis efficiency. The performance of the engineered system is evaluated using multiple criteria, including PET weight loss, changes in surface chemistry (FTIR), metabolite production, and surface morphology (SEM). Our findings will demonstrate the potential of Geobacillus spp. as a whole-cell thermophilic biocatalyst capable of simultaneous enzyme production and PET degradation, overcoming limitations associated with mesophilic systems and ex situ enzyme application. |
|---|