López-Teijeiro Adrián, Barreiro-Piñeiro Natalia, Eibes Gemma, Martínez-Costas Jose
Centre for Research in Biological Chemistry and Molecular Materials (CiQUS), Department of Biochemistry and Molecular Biology, Universidade de Santiago de Compostela, Santiago de Compostela 15782, Spain.
CRETUS, Department of Chemical Engineering, Universidade de Santiago de Compostela, Santiago de Compostela 15782, Spain.
J Hazard Mater. 2025 Sep 5;495:138789. doi: 10.1016/j.jhazmat.2025.138789. Epub 2025 May 30.
The accumulation of plastics in the environment has become a serious concern for the entire society. In recent years, enzyme-based biodegradation has emerged as a promising and sustainable strategy for the recycling of polyethylene terephthalate (PET), one of the most widely used polyester plastics. However, the translation of these technologies to the industrial field faces several underexplored challenges, including the immobilization and reusability of the biocatalysts. Here, we present the use of IC-Tagging as a novel one-step methodology for the "in cellulo" self-immobilization of the benchmark PET-degrading enzyme LCC in protein nanospheres. The immobilized enzyme showed to be active against soluble substrates and exhibited improved thermal resistance and long-term storage stability, retaining 58 % of relative activity after 3 months at room temperature. Immobilized LCC also demonstrates remarkable reusability, with minor activity loss up to 10 reuse cycles. Most importantly, nearly complete depolymerization (>90 %) of various untreated amorphous post-consumer PET materials was achieved at a wide range of temperatures (50-70 °C) by removing the products and reusing the enzyme repeatedly. Furthermore, reutilization led to almost full degradation of two consecutive batches of post-consumer PET in 6 days, outperforming all immobilized biocatalysts reported at laboratory scale. Overall, IC-Tagging emerges as a promising and versatile platform for the production, immobilization and reutilization of top-performing PET hydrolases, contributing to sustainable management of plastic waste.
环境中塑料的积累已成为整个社会严重关切的问题。近年来，基于酶的生物降解已成为聚对苯二甲酸乙二酯（PET）回收利用的一种有前景且可持续的策略，PET是使用最广泛的聚酯塑料之一。然而，将这些技术转化到工业领域面临一些尚未充分探索的挑战，包括生物催化剂的固定化和可重复使用性。在此，我们展示了使用IC标记作为一种新颖的一步法，用于在蛋白质纳米球中对基准PET降解酶LCC进行“细胞内”自固定化。固定化酶对可溶性底物具有活性，并表现出更高的耐热性和长期储存稳定性，在室温下放置3个月后仍保留58%的相对活性。固定化LCC还表现出显著的可重复使用性，在多达10个重复使用循环中活性损失较小。最重要的是，通过去除产物并反复使用酶，在广泛的温度范围（50 - 70°C）内实现了各种未经处理的无定形消费后PET材料的几乎完全解聚（>90%）。此外，重复利用在6天内使两批连续的消费后PET几乎完全降解，优于实验室规模报道的所有固定化生物催化剂。总体而言，IC标记成为生产、固定化和再利用高性能PET水解酶的一个有前景且通用的平台，有助于塑料废物的可持续管理。
