Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, PR China.
J Am Chem Soc. 2013 Jan 30;135(4):1272-5. doi: 10.1021/ja3120136. Epub 2013 Jan 17.
We report a rational design of CaHPO(4)-α-amylase hybrid nanobiocatalytic system based on allosteric effect and an explanation of the increase in catalytic activity when certain enzymes are immobilized in specific nanomaterials. Employing a calcification approach in aqueous solutions, we acquired such new nanobiocatalytic systems with three different morphologies, i.e., nanoflowers, nanoplates, and parallel hexahedrons. Through studying enzymatic performance of these systems and free α-amylase with/without Ca(2+), we demonstrated how two factors, allosteric regulation and morphology of the as-synthesized nanostructures, predominantly influence enzymatic activity. Benefiting from both the allosteric modulation and its hierarchical structure, CaHPO(4)-α-amylase hybrid nanoflowers exhibited dramatically enhanced enzymatic activity. As a bonus, the new system we devised was found to enjoy higher stability and durability than free α-amylase plus Ca(2+).
我们报告了一种基于别构效应的 CaHPO(4)-α-淀粉酶杂化纳米生物催化体系的合理设计，并解释了某些酶固定在特定纳米材料中时催化活性增加的原因。我们采用水相钙化方法，获得了具有三种不同形态的新型纳米生物催化体系，即纳米花、纳米板和平行六面体。通过研究这些体系和游离α-淀粉酶在有/无 Ca(2+)条件下的酶促性能，我们展示了两种因素，即别构调节和合成纳米结构的形态，如何主要影响酶活性。得益于别构调节和分级结构，CaHPO(4)-α-淀粉酶杂化纳米花表现出显著增强的酶活性。此外，我们设计的新体系比游离α-淀粉酶加 Ca(2+)具有更高的稳定性和耐久性。
