聚对苯二甲酸乙二醇酯降解酶的研究进展

Advance in polyethylene terephthalate degrading enzyme

摘要:

聚对苯二甲酸乙二醇酯（Polyethylene terephthalate，PET）因其良好的耐用性和可塑性，已在世界范围内的工业领域和日常生活中得到广泛应用。目前自然环境中大量PET使用废弃物的积累和迁移给全球生态系统带来了严重负担，因此PET的降解问题已成为全球性的热点问题。微生物酶降解法目前被认为是一种理想绿色PET降解方法，有希望应用于大规模降解PET废弃物降解处理。传统的PET降解酶主要包括脂肪酶、酯酶和角质酶等，但这些酶的PET降解活性相对不高。近期科学家从Ideonella sakaiensis细菌中分离了一种新型水解酶PETase，能够特异性高效降解PET。本文从结构生物学角度对多种PET降解酶进行梳理，重点总结了新近发现的PETase催化机制，为发展改造更有效的PET降解酶提供理论依据。

Abstract:

Polyethylene terephthalate is one of the most used synthetic polymers in industrial fields and daily life due to its excellent durability and plasticity. In the meantime, a large amount of PET waste has caused severe environmental problems, so that researchers are paying more and more attention to the degradability of PET waste. Among all of the methods of plastic degradation, the means of biodegradation is considered to be the most environmental-friendly treatment at present and it will be efficient for large-scale degradation of PET waste. Previous research has indicated that PET degrading enzymes mainly include lipases, esterases and cutinases, but they exhibit poor PET degradation activity. A new PETase discovered recently, which is isolated from Ideonella sakaiensis, has shown high efficacy and specificity to degradation of PET materials. Here, we summarize the progress on structural research of PET degrading enzymes and describe the catalytic mechanism of PETase, to help modify more effective PET degrading enzymes.