Institute for Environmental Biotechnology, IFA Tulln, University of Natural Resources and Life Sciences, Vienna, Austria; ACIB-Austrian Centre of Industrial Biotechnology, Graz, Austria.
Institute for Environmental Biotechnology, IFA Tulln, University of Natural Resources and Life Sciences, Vienna, Austria.
Methods Enzymol. 2021;648:293-315. doi: 10.1016/bs.mie.2020.12.010. Epub 2020 Dec 29.
In the past years, several serine hydrolases such as cutinases, esterases and lipases have shown the ability to degrade not only natural polymers but also synthetic polyesters, even aromatic representatives like polyethylene terephthalate (PET). Hence, cutinases and related ester hydrolases have become very important to be applied in the biocatalytic plastic recycling as green alternative to chemical recycling as well as to the functionalization of polyester surfaces in order to change superficial properties like hydrophobicity or hydrophilicity. Sorption characteristics of the enzymes to the polymers have turned out to be a crucial process for efficient polymer hydrolysis. Hence, special attention was paid on tuning the sorption of the enzymes to the hydrophobic polymers. Engineering of the enzyme surface, fusion of hydrophobic substrate-binding domains or truncation of domains hindering the access of the polymer to the enzyme has led to significant improvement of sorption processes and consequently increased activity on the bulky substrate. Finally, the combination of engineering approaches has proved that they can bring additional advantages in improving the enzyme activity when used in a synergistic manner.
在过去的几年中，几种丝氨酸水解酶，如角质酶、酯酶和脂肪酶，已经显示出不仅能够降解天然聚合物，还能够降解合成聚酯，甚至是芳香族代表聚对苯二甲酸乙二醇酯（PET）的能力。因此，角质酶和相关的酯水解酶在生物催化塑料回收中变得非常重要，它们是化学回收的绿色替代品，也是聚酯表面的功能化，以改变疏水性或亲水性等表面性质。酶对聚合物的吸附特性已成为有效聚合物水解的关键过程。因此，特别关注酶对疏水性聚合物的吸附的调谐。酶表面的工程改造、疏水底物结合结构域的融合或阻碍聚合物与酶接触的结构域的截断，导致吸附过程的显著改善，从而在大块底物上增加了活性。最后，工程方法的结合证明，当以协同方式使用时，它们可以在提高酶活性方面带来额外的优势。
