One-Pot Microbial Cell Factory Strategy for the Production of Protocatechuic Acid from Polyethylene Terephthalate Waste

Microbial systems have the capacity to convert raw materials that come from plant sources to fine chemicals under environmental conditions. Considering the costs of land production and biomass deconstruction, the range of available raw materials for microbial systems should be expanded. Within, the utilization of plastic waste as feedstock was instructive. Herein, we constructed a microbial cell factory through engineered Escherichia coli to convert polyethylene terephthalate (PET) waste into a value-added product, protocatechuic acid (PCA). PCA is a natural phenolic acid with numerous pharmacological properties. To overcome the issue that PET solid could not enter the cell membrane, we divided the biocatalytic pathway into two cell modules. By utilization of outer membrane protein A (OmpA) to display FAST PETase on the cell surface, PET is degraded into TPA monomers, which can then conveniently diffuse through the cell membrane and enter the biological upcycling pathway for PCA production within the cell. Overall, the designed cell factories can directly convert PET waste plastics into PCA in a one-pot manner. Thus, this one-pot approach has developed a universal cell platform for directly treating potential substrates that do not have cell membrane permeability, providing an important basis for the sustainable degradation and up-evaluation of solid waste.