Jiang Caiping, Zhai Kairui, Wright R Clay, Chen Juhong
Department of Biological Systems Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States.
Department of Bioengineering, University of California, Riverside, Riverside, California 92521, United States.
ACS Synth Biol. 2025 Jul 18;14(7):2810-2820. doi: 10.1021/acssynbio.5c00209. Epub 2025 Jul 2.
Due to its low cost of manufacturing, poly(ethylene terephthalate) (PET, a polyester plastic) has been the most widely used plastic material for food packaging. However, PET is nonbiodegradable. It can take years to degrade when it is discarded into the environment. In recent years, plastic pollution has received much attention and has become a major environmental issue. In this study, we engineered yeast surfaces to display two PET-degrading enzymes (PETase and MHETase) to degrade PET plastics. The enzymes displayed on the yeast surface were characterized by using confocal microscopy and flow cytometry. The reaction conditions to degrade PET plastics using the engineered yeasts were optimal at pH 9 and 30 °C. In addition, the engineered yeasts showed great stability and reusability to degrade PET films. Furthermore, we demonstrated that the engineered yeasts as whole-cell catalysts can be used to degrade drinking water bottles into value-added products. This study provides a novel whole-cell biocatalyst using engineered yeasts to degrade plastic waste, offering a new strategy to solve plastic pollution and recycling challenges.
由于聚对苯二甲酸乙二酯（PET，一种聚酯塑料）的制造成本较低，它一直是食品包装中使用最广泛的塑料材料。然而，PET是不可生物降解的。当它被丢弃到环境中时，可能需要数年时间才能降解。近年来，塑料污染受到了广泛关注，并已成为一个主要的环境问题。在本研究中，我们对酵母表面进行工程改造，使其展示两种PET降解酶（PETase和MHETase）以降解PET塑料。通过共聚焦显微镜和流式细胞术对酵母表面展示的酶进行了表征。使用工程酵母降解PET塑料的反应条件在pH 9和30°C时最为适宜。此外，工程酵母在降解PET薄膜方面表现出很高的稳定性和可重复使用性。此外，我们证明了作为全细胞催化剂的工程酵母可用于将饮用水瓶降解为增值产品。本研究提供了一种利用工程酵母降解塑料废物的新型全细胞生物催化剂，为解决塑料污染和回收挑战提供了新策略。
