School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan, 030006, China.
Engineering Research Center of Ministry of Education for Fine Chemicals, Shanxi University, Taiyuan, 030006, China.
Nat Commun. 2024 Nov 30;15(1):10440. doi: 10.1038/s41467-024-54725-w.
The artificial engineering of an enzyme's structural conformation and dynamic properties to promote its catalytic activity and stability outside cellular environments is highly pursued in industrial biotechnology. Here, we describe an elegant strategy of combining the rationally designed liquid-solid hybrid microreactor with a tailor-made polyethylene glycol functional ionic liquid (PEG-IL) microenvironment to exercise a high level of control over the configuration of enzymes for practical continuous-flow biocatalysis. As exemplified by a lipase driven kinetic resolution reaction, the obtained system exhibits a 2.70 to 30.35-fold activity enhancement compared to their batch or traditional IL-based counterparts. Also, our results demonstrate that the thermal stability of encapsulated lipase can be significantly strengthened in the presence of PEG groups, showcasing a long-term continuous-flow stability even up to 1000 h at evaluated temperature of 60 C. Through systematic experiment and molecular dynamics simulation studies, the conformational changes of the active site cavity in the modified lipases are correlated with enzymatic properties alteration, and the pronounced effects of PEG-groups in stabilizing enzyme's secondary structures by delaying unfolding at elevated temperatures are identified. We believe that this study will guide the design of high-performance enzymatic systems, promoting their utilization in real-world biocatalysis applications.
在工业生物技术中，人们高度追求通过人工工程来改变酶的结构构象和动态特性，以提高其在细胞外环境中的催化活性和稳定性。在这里，我们描述了一种巧妙的策略，即将合理设计的液-固混合微反应器与定制的聚乙二醇功能离子液体（PEG-IL）微环境相结合，对酶的构象进行高度控制，以实现实用的连续流生物催化。以脂肪酶驱动的动力学拆分反应为例，与分批或传统 IL 基对应物相比，所获得的系统表现出 2.70 至 30.35 倍的活性增强。此外，我们的结果表明，在 PEG 基团存在下，包封脂肪酶的热稳定性可以得到显著增强，在评估温度为 60°C 的情况下，甚至可以在长达 1000 小时的连续流动稳定性下展示。通过系统的实验和分子动力学模拟研究，我们将活性位点腔的构象变化与酶性质的改变相关联，并确定了 PEG 基团在通过延迟高温下的展开来稳定酶的二级结构方面的显著作用。我们相信，这项研究将指导高性能酶系统的设计，促进其在实际生物催化应用中的应用。
