Structure and Surface Reactivity Mediated Enzymatic Performances of Clay-Based Nanobiocatalyst

The nanobiocatalyst is an emerging innovation that synergistically integrates advanced nanotechnology with biotechnology for improving enzyme activity, stability, capability and engineering performances. Enzymes and clay minerals are two important essential substances in the earth. As the important nanostructured minerals, clay minerals have played an important role in enzyme-related biochemical processes such as the origin and evolution of life, soil ecological environment, pollution remediation and element geochemical cycling, and even some clay minerals have intrinsic enzymatic activities. Based on the study of clay minerals-based enzyme-like activities and enzymatic catalysis in confined environment by clay minerals, lipase and 3-aminopropyltriethoxysilane (APTES) functionalized montmorillonite (Mt) were selected to biomimetic construct lipase-Mt nanobiocatalyst. Experimental results indicated that lipase-Mt activity was 40.65 U/mg, which was nearly 4-fold higher than that of free lipase under optimal conditions. The kinetic parameters of K-m and V-max for lipase-Mt were 3.406 mM and 312.5 mM/L min, respectively, indicating a higher affinity of the immobilized lipase in nanobiocatalyst towards the substrate compared with free lipase. The present study has provided a promising way for screening, optimizing and rational design of efficient nanomineral-based enzymatic nanobiocatalyst.