Repurposing of waste PET by microbial biotransformation to functionalized materials for additive manufacturing.

Plastic waste is an outstanding environmental thread. Poly (ethylene terephthalate) (PET) is one of the most abundantly produced single-use plastics worldwide, while its recycling rates are low. In parallel, additive manufacturing is a rapidly evolving technology with wide-ranging applications. Thus, there is a need for a broad spectrum of polymers to meet the demands of this growing industry and address post-use waste materials. This perspective article highlights the potential of designing microbial cell factories to upcycle PET into functionalized chemical building blocks for additive manufacturing. We present the leveraging of PET hydrolyzing enzymes and rewiring the bacterial C2 and aromatic catabolic pathways to obtain high-value chemicals and polymers. Since PET mechanical recycling back to original materials is cost-prohibitive, the biochemical technology is a viable alternative to upcycle PET into novel 3D printing materials, such as replacements for acrylonitrile butadiene styrene (ABS). The presented hybrid chemo-bio approaches potentially enable the manufacturing of environmentally friendly degradable or higher-value high-performance polymers and composites and their reuse for a circular economy.