Chemical Synthesis of the Mirror‐Image Fast‐PETase by the Enzyme‐Cleavable Solubilizing‐Tag Strategy

Abstract Mirror‐image poly(ethylene terephthalate) (PET) plastic‐degrading enzymes have emerged as promising biocatalytic platforms due to their exceptional enzymatic stability and low immunogenicity. Currently, the sole reported mirror‐image plastic‐degrading enzyme, the D‐form of 231‐residue PET hydrolase ICCG (engineered leaf‐branch compost cutinase variant), suffers from thermophilic activity requirements, which limits its practical applications. Here, the first total chemical synthesis of a mirror‐image 271‐residue D‐Fast‐PETase was presented by using an enzyme‐cleavable solubilizing tag strategy. Comparative kinetic analysis revealed that D‐Fast‐PETase showed a remarkable increase (∼20‐fold within 24 hours) in PET degradation efficiency compared to D‐ICCG at temperatures of 37 °C, making it a promising candidate for prolonged PET decomposition in open environments and holding potential in addressing microplastic‐related health issues within the biomedical field. This work not only expands the chemical biology toolbox for mirror‐image enzyme synthesis but also establishes D‐Fast‐PETase as a candidate in combating the dual crises of global plastic pollution and microplastic‐associated health risks.