基于多孔框架材料构建新型非均相多酶协同催化体系

Multi-enzyme cooperation system can construct multi-step cascade biocatalysis and produce valuable target products. As an emerging biocatalytic technology, it has great potential in many fields. However, some challenges have hinder the applications of homogeneous multi-enzyme system: the cooperation efficiency between enzymes is relatively low; low catalytic efficiency; high cost; poor stability. Herein, we propose to construct novel heterogenous multi-step cascade biocatalytic platforms based on porous framework materials (MOFs and COFs), and combine their advantages in both biomimetic technology and enzyme immobilization to establish heterogeneous multi-step biocatalysis sysyems. Firstly, based on the selected biocatalytic pathway, we will design and synthesize porous framework materials with biomimetic activity of targest enzymes, then use these materials to immobilize the synergy enzymes for multi-step cascade biocatalysis. In this system, the active centers of enzymes can be integrated in one biocatalyst and located in a restricted region for high efficiency synergy, which will overcome the deficiency caused by the random arrangement of enzymes. On the other hand, the rational design of porous materials and the utilization of their structural flexibility (such as hierarchical porosity and pore modification) to form substrate channeling and further improve catalytic efficiency. In addition, we will investigate the mechanisms in this novel system, such as the interactions between the enzyme and the porous material to further improve the system, and provide the guidance for related usage of those materials in other systems. By establishing this high efficient heterogeneous biocatalytic platform, we will pave the path for medicinal and other industrial applications of porous framework materials.

多酶催化通过构建多步协同的生物催化体系以获得目标产物，近年来发展迅速，具有很大的应用潜力。然而其均相体系的应用存在诸多挑战：如酶之间协同性差、高成本、稳定性差等。本项目基于新型多孔框架材料（MOFs和COFs），利用功能配合物等框架材料的结构和性质特点，结合其在模拟酶和固定化酶方面的优势，构建新型非均相多酶催化平台。根据所设计的多酶催化反应路线要求，首先设计具有模拟酶功能的多孔框架材料，利用其对天然酶精确固定，将不同酶的活性中心整合在特定区域内，实现其高效协同，以解决均相多酶体系中酶无序排布、协同性差的问题。通过对多孔框架材料进行理性设计，利用其多级孔道结构和孔道修饰，建立底物通路，提高催化效率。并深入研究酶与多孔框架材料的相互作用等内在机理，进一步优化提高体系的效率，指导多孔框架材料应用于生物催化等相关领域。最终构建高效的非均相多酶催化体系，并实现其在生物、医药等领域的应用。

酶作为一种天然的特异性催化剂，具有高效性、专一性、多样性等诸多特性。随着“酶工程”的崛起，生物催化在化学、医药、食品及化工等领域得到日益广泛的应用。但是，作为生物催化剂的酶有其自身的局限性，如对外界条件敏感、不稳定等。这些特性，决定了多酶协同的生物催化操作受限，也阻碍了生物催化的工业化应用。利用固定化技术提升生物催化剂的稳定性，重复利用性和可操作性，是促进生物合成产业化应用的有效途径和关键环节。本项目创新性的将固定化酶和生物模拟技术相结合，充分利用其各自的优点，用具有模拟酶等功能的多孔框架材料和多孔高分子金属配合物材料固定天然酶分子，构建高效的非均相多酶协同体系。项目团队从固定化酶的载体和策略两方面入手进行创新，创制了一系列适合不同应用场景的高性能固定化载体介质和固定化新技术，突破了大内腔高稳定性固定化酶载体的构建难题，成功实现多酶在非均相生物催化体系中的级联应用，并实现了在固定化体系中催化元件的高效协同，为多酶催化的非均相催化及相关酶反应器的构建提供的全新解决方案。此外，本项目借助多种表征和分析技术，深入研究固定化过程内在机理，开拓了具有优异普适性的新型生物催化平台。基于本项目支持，在J. Am. Chem. Soc., Angew Chem. Int. Ed., Chem. Soc. Rev.等高水平学术期刊发表论文13篇，获批或申请中国发明专利3件。本项目执行达到或高于项目预定目标，构建了应用前景广阔的新型生物催化平台性技术，具有重要的科学和应用价值。