解聚
催化作用
聚对苯二甲酸乙二醇酯
水解酶
化学
聚乙烯
机制(生物学)
无定形固体
酶
有机化学
化学工程
材料科学
高分子化学
哲学
认识论
工程类
复合材料
作者
Mingna Zheng,Yanwei Li,Weiliang Dong,Qingzhu Zhang,Wenxing Wang
出处
期刊:ACS Sustainable Chemistry & Engineering
[American Chemical Society]
日期:2024-06-27
卷期号:12 (27): 10252-10259
标识
DOI:10.1021/acssuschemeng.4c02986
摘要
Enzyme-based recycling of the extensively utilized polyethylene terephthalate (PET) is considered as a promising eco-friendly strategy to manage PET waste. Although efficient depolymerization of amorphous PET has been achieved, highly efficient depolymerization of the well-ordered crystalline region of PET presents a huge challenge. Herein, leveraged to molecular dynamics simulations and quantum mechanics/molecular mechanics calculations, we study the depolymerization mechanism of IsPETase toward both crystalline and amorphous PET to unravel the origin of the efficient depolymerization of the amorphous region. We demonstrated that crystalline PET is not well accommodated within the active pocket, and significant distortion energy is needed during its depolymerization. Poor stabilization within the oxyanion hole for crystalline PET was identified and confirmed to lead to higher energy barriers. In addition, after identifying the rate-determining step, we reveal that IsPETase prefers to depolymerize trans than gauche conformation of the PET polymer with a 2.4 kcal mol–1 lower energy barrier. Differences in structural/charge distributions within the active site of the enzyme between trans and gauche conformations were proposed to be responsible for this preference. The structure-charge-activity relationship for the rate-determining step was built. Our results will aid the rational engineering of PETases with high depolymerization efficiency toward the crystalline region of PET for fighting the challenges of industrial applications.
科研通智能强力驱动
Strongly Powered by AbleSci AI