Meyer Cifuentes Ingrid E, Wu Pan, Zhao Yipei, Liu Weidong, Neumann-Schaal Meina, Pfaff Lara, Barys Justyna, Li Zhishuai, Gao Jian, Han Xu, Bornscheuer Uwe T, Wei Ren, Öztürk Başak
Junior Research Group Microbial Biotechnology, Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany.
Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.
Front Bioeng Biotechnol. 2022 Jul 21;10:930140. doi: 10.3389/fbioe.2022.930140. eCollection 2022.
Polybutylene adipate terephthalate (PBAT) is a biodegradable alternative to polyethylene and can be broadly used in various applications. These polymers can be degraded by hydrolases of terrestrial and aquatic origin. In a previous study, we identified tandem PETase-like hydrolases (Ples) from the marine microbial consortium I1 that were highly expressed when a PBAT blend was supplied as the only carbon source. In this study, the tandem Ples, Ple628 and Ple629, were recombinantly expressed and characterized. Both enzymes are mesophilic and active on a wide range of oligomers. The activities of the Ples differed greatly when model substrates, PBAT-modified polymers or PET nanoparticles were supplied. Ple629 was always more active than Ple628. Crystal structures of Ple628 and Ple629 revealed a structural similarity to other PETases and can be classified as member of the PETases IIa subclass, α/β hydrolase superfamily. Our results show that the predicted functions of Ple628 and Ple629 agree with the bioinformatic predictions, and these enzymes play a significant role in the plastic degradation by the consortium.
聚己二酸对苯二甲酸丁二醇酯（PBAT）是聚乙烯的一种可生物降解替代品，可广泛应用于各种领域。这些聚合物可被陆生和水生来源的水解酶降解。在之前的一项研究中，我们从海洋微生物群落I1中鉴定出串联的类PETase水解酶（Ples），当以PBAT共混物作为唯一碳源时，这些酶会高度表达。在本研究中，对串联Ples，即Ple628和Ple629进行了重组表达和特性分析。这两种酶都是嗜温酶，对多种低聚物都有活性。当提供模型底物、PBAT改性聚合物或PET纳米颗粒时，Ples的活性差异很大。Ple629总是比Ple628更具活性。Ple628和Ple629的晶体结构显示出与其他PETase的结构相似性，可归类为PETases IIa亚类、α/β水解酶超家族的成员。我们的结果表明，Ple628和Ple629的预测功能与生物信息学预测一致，并且这些酶在该群落的塑料降解中发挥着重要作用。
