Chen_2024_Chem.Eng.J_481_148418

Using enzymes to decompose poly(ethylene terephthalate) (PET) is an attractive strategy to the sustainable utilization of PET, and an effective production platform of PET degrading enzyme is a prerequisite to achieve this goal. Here, we exploited the industrial yeast strain Pichia pastoris to produce a potent PET hydrolase termed FAST-PETase, whose performance was further elevated by removing two N-linked glycosylations through molecular engineering. The expression of the yielded variant, FAST-PETase-212/277, was elevated by antibiotics selection and chaperon co-expression to exceed 3 g/L in a 30-L fermenter. Notably, the crude fermentation product can be directly applied to decompose PET without purification. More than 95 % postconsumer PET can be achieved by 0.5 mgenzyme gPET-1 in 24 h in a 10-L reaction system in a reactor. These results demonstrate the economic viability of producing PET hydrolytic enzyme with modern fermentation facilities for large scale PET decomposition.