25. Immobilization of Coupled Enzymes onto Metalated Hierarchical Organic Microspheres

Y. Li, W. Wang, Y. Sun, J. Fan, H. Zhang*, P. Ji*

Hierarchical organic microspheres (HOMs) have emerged as an ideal carrier for immobilizing biomacromolecules. In this research, an in-depth investigation into the structural characteristics of a striated HOM, known as HOM-15, has revealed the assembly mechanism of microspheres through weakly stacked two-dimensional structural units that are composed of V-shaped small organic molecules. With the leverage of this understanding, HOM-15 was adopted as a stable and reusable platform for co-immobilizing of ene-reductases and glucose dehydrogenases via metal ion bridging onto the surface of HOMs. The research demonstrates that metal ion bridging can finely tune the surface properties of HOM-15, thereby facilitating the immobilization of enzymes that would otherwise be impeded by electrostatic repulsion. Comparing HOM-15 to other microspherical variants revealed its superior biocatalytic performance, attributed to the reduction of the mass transfer barrier facilitated by its lamellar-stacking morphology. This novel biocatalytic system underscores the potential applications of HOMs in broader biocatalytic processes.

多级有机微球（HOM）已成为固定生物大分子的理想载体。本研究深入研究了一种条纹状HOM（称为HOM-15）的结构特征，揭示了微球通过由V形小有机分子组成的弱堆叠二维结构单元的组装机制。基于这一认识，HOM-15被用作稳定且可重复使用的平台，通过金属离子桥接将烯还原酶和葡萄糖脱氢酶共固定到HOM表面。研究表明，金属离子桥接可以精细地调节HOM-15的表面特性，从而促进酶的固定，否则这些酶会因静电排斥而受到阻碍。将HOM-15与其他微球变体进行比较，发现其具有优异的生物催化性能，这归因于其层状堆叠形态有助于降低传质屏障。这种新颖的生物催化系统强调了 HOMs 在更广泛的生物催化过程中的潜在应用。