Novel Feruloyl Esterase for the Degradation of Polyethylene Terephthalate (PET) Screened from the Gut Microbiome of Plastic-Degrading Mealworms ( Tenebrio Molitor Larvae)

作者：Tursunay Mamtimin, Xingyu Ouyang, Wei‐Min Wu, Tuoyu Zhou, Xiaoxiao Hou, Aman Khan, Pu Liu, Yi‐Lei Zhao, Hongzhi Tang, Craig S. Criddle, Huawen Han, Xiangkai Li · 发表于：Environmental Science & Technology · 年份：2024 · DOI：10.1021/acs.est.4c01495 · 被引用次数：35 · 研究领域：Microplastics and Plastic Pollution、Pharmaceutical and Antibiotic Environmental Impacts、biodegradable polymer synthesis and properties

Mealworms ( Tenebrio molitor ) larvae can degrade both plastics and lignocellulose through synergistic biological activities of their gut microbiota because they share similarities in chemical and physical properties. Here, a total of 428 genes encoding lignocellulose-degrading enzymes were screened from the gut microbiome of T. molitor larvae to identify poly(ethylene terephthalate) (PET)-degrading activities. Five genes were successfully expressed in E. coli, among which a feruloyl esterase-like enzyme named Tm Fae-PETase demonstrated the highest PET degradation activity, converting PET into MHET (0.7 mg MHETeq ·h –1 ·mg enzyme –1 ) and TPA (0.2 mg TPAeq ·h –1 ·mg enzyme –1 ) at 50 °C. Tm Fae-PETase showed a preference for the hydrolysis of ferulic acid methyl ester (MFA) in the presence of both PET and MFA. Site-directed mutagenesis and molecular dynamics simulations of Tm Fae-PETase revealed similar catalytic mechanisms for both PET and MFA. Tm Fae-PETase effectively depolymerized commercial PET, making it a promising candidate for application. Additionally, the known PET hydrolases Is PETase, FsC, and LCC also hydrolyzed MFA, indicating a potential origin of PET hydrolytic activity from its lignocellulosic-degrading abilities. This study provides an innovative strategy for screening PET-degrading enzymes identified from lignocellulose degradation-related enzymes within the gut microbiome of plastic-degrading mealworms. This discovery expands the existing pool of plastic-...