Enhancing Enzyme Activity Using Hydrophilic Hollow Layered Double Hydroxides as Encapsulation Carriers

Abstract

Enzyme immobilization enables the fabrication of flexible and powerful biocatalytic systems that can meet the needs of green and efficient development in various fields. However, restricted electron and mass transfer during enzymatic reactions and disruption of the enzyme structure during encapsulation limit the wide application of the immobilized enzyme systems. Herein, we report an encapsulation strategy based on hollow-shell-layered double hydroxides (LDHs; ZnCo-LDH) for green and nondestructive enzyme immobilization. Benefiting from the protective and enzyme-friendly microenvironment provided by the hydrophilic hollow structure of ZnCo-LDH, the encapsulated enzyme maintains a nearly natural enzyme biostructure and enhanced stability. Notably, mesoporous ZnCo-LDH with excellent electrical properties considerably facilitates electron and mass transport during enzymatic reactions, exhibiting 5.56 times the catalytic efficiency of free enzymes or traditional enzyme encapsulation systems. The current study broadens the family of encapsulated carriers and alleviates the trade-off between enzyme stability and catalytic activity in the encapsulated state, presenting a promising avenue for the industrial application of the enzyme.

Immobilized Dipeptidase in Manganese Ion-Loaded Polyethylenimine-Induced Calcium Phosphate Nanocrystals for Carnosine Synthesis

“…Enzyme immobilization is usually used to improve enzyme activity and stability, in which the structure of the enzyme is relatively fixed and the enzyme is protected from denaturation by the carrier. − Organic–inorganic hybrid nanomaterials, metal–organic frameworks, covalent organic frameworks, and mesoporous silica are important carriers for enzyme immobilization. − Among them, the organic–inorganic hybrid nanoflower has the advantages of high specific surface area and easy synthesis. , Due to the activation of the enzyme by metal ions and restriction of nanoflowers, the activity and stability of enzyme-inorganic hybrid nanoflowers could be improved as compared with free enzymes. , In addition, some non-protein molecules could also form organic–inorganic hybrid nanoflowers with metal ions, which showed peroxidase mimetic activity through the Fenton-like mechanism and could serve as promising nanobiocatalysts for free radical polymerization . However, the long synthesis time, low synthetic yield, and poor structural stability of conventional organic–inorganic hybrid nanomaterials have limited their application in industrial production. , To overcome these drawbacks, some researchers have exploited the property that some biomacromolecules can reduce the nucleation barrier of crystals and thus to accelerate the nucleation and growth of inorganic minerals to develop a rapid synthesis scheme of organic–inorganic hybrid nanoflowers, and demonstrated their great potential for biocatalyst applications. , Among them, biomacromolecules rich in carboxyl, hydroxyl, and amino groups are the most significant.…”

Enhancing Chymotrypsin Activity and Stability of Capillary Immobilized Enzyme Microreactors Using Zeolitic Imidazolate Frameworks as Encapsulation Materials

“…Metal–organic frameworks (MOFs) are organic–inorganic hybrid materials with intramolecular pores formed by the self-assembly of organic ligands and inorganic metal ions or clusters through coordination bonds. − Compared to conventional inorganic porous materials, − MOFs offer adjustable high porosity, high specific surface area, and a diverse range of framework compositions. − In recent years, MOFs as carriers to in situ encapsulate free enzymes by coincubation of enzymes and MOFs precursors through biomineralization have received a lot of attention from researchers. − Enzyme in situ encapsulation inside MOFs can not only significantly increase the enzyme loading amount but also facilitate the enzyme catalytic process through the substrate selectivity of MOFs pore size and enzyme microenvironment, significantly increasing enzyme activity . In addition, the rigid domain-limiting structure of the MOFs skeleton can limit the conformational changes of the enzyme, and thus MOFs can be used as an external protective layer for encapsulating the enzyme, thereby further improving the stability of the enzyme. , Inspired by these excellent works, we speculate that in situ encapsulation of enzymes in capillaries to prepare OT-IMERs may significantly reduce the influence of the external environment and complex sample matrices on enzyme activity and stability.…”

A Hydrophilic Metal Azolate Coordination Polymer for In Situ Encapsulation of Haloalkane Dehalogenase with Enhanced Enzymatic Performance

“…As an important kind of catalyst, enzymes have been widely used in various fields, such as pharmaceutical, food, and brewing industries . However, the fragile nature of enzymes (low stability at high temperature, poor tolerance to organic solvents, and difficulty in separation and reusability) increases cost and impairs catalytic effects, consequently limiting broader applications of the biocatalysts . A variety of approaches including chemical modification, cross-linking, and immobilization have been used to improve the catalytic performance of enzymes under harsh conditions. , In the past decade, metal–organic frameworks (MOFs), a class of materials that are synthesized via coordination between metal ions and organic ligands, have become a valuable platform for enzyme immobilization, − and some of the MOF-immobilized enzymes exhibited extraordinary stability as well as maintained the initial activity for multiple cycles. − …”