Enhancing Enzyme Activity by the Modulation of Covalent Interactions in the Confined Channels of Covalent Organic Frameworks

Abstract

Controllable regulations on the enzyme conformation to optimize catalytic performance are highly desired for the immobilized biocatalysts yet remain challenging. Covalent organic frameworks (COFs) possess confined channels with finely tunable pore environment, offering a promising platform for enzyme encapsulation. Herein, we covalently immobilized the cytochrome c (Cyt c) in the size‐matched channels of COFs with different contents of anchoring site, and significant enhancement of the stability and activity (≈600 % relative activity compared with free enzyme) can be realized by optimizing the covalent interactions. Structural analyses on the immobilized Cyt c suggest that covalent bonding could induce conformational perturbation resulting in more accessible active sites. The effectiveness of the covalent interaction modulation together with the tailorable confined channels of COFs offers promise to develop high‐performance biocatalysts.

Confining enzymes in porous organic frameworks: from synthetic strategy and characterization to healthcare applications

“…Recently, Wang et al reported an enhancement in enzyme activity by modulating the covalent interactions in the confined channels of COFs. 211 By tuning the contents of the anchoring sites in the COF channels, significant activity enhancement and structural stability of the enzymes were achieved. This work demonstrated that the modulation of the covalent interactions could induce a disturbance in the enzyme conformation, resulting in the higher accessibility of the active sites of the enzymes.…”

Covalent Organic Frameworks as a Biomacromolecule Immobilization Platform for Biomedical and Related Applications

“…The effectiveness of the covalent interaction modulation and the customizable finite pore channels of COF offer promise for developing highperformance biocatalysts. [71] In 2021, for applications in long-term starvation therapy and photodynamic therapy (PDT), Wan's group constructed an enzymatic nanocapsule based on porphyrin-based COF to load GOx and CAT (Figure 8b). This system combined starvation therapy and PDT by co-immobilizing the two enzymes, which had a better therapeutic effect than ordinary monotherapy.…”

“…This material had a long-range-ordered structure in which building blocks were controlled in 2D or 3D space to form pores with uniform diameters Reproduced with permission. [71] Copyright 2022, Wiley-VCH GmbH. b) Schematic illustration of the preparation of the nanopocket and the enzyme catalytic reactions for cancer therapy.…”

“…Figure 8. a) Schematic illustration of covalent immobilization of Cyt-c in the confined channel of COF. Reproduced with permission [71]. Copyright 2022, Wiley-VCH GmbH.…”

Molecular insight into CO2/N2 separation using a 2D-COF supported ionic liquid membrane

“…E-mail: zhangjun.upc@gmail.com b College of Science, China University of Petroleum, Qingdao 266000, P. R. China benefit from their atomic thickness, high density, and, uniform and adjustable pore size. [25][26][27][28] However, it has been reported that the minimum pore size in both COFs and 2D-polymers is in the range of 0.5-4.7 nm, [29][30][31][32] whereas the kinetic diameter of common gas pairs is in range of 0.25-0.4 nm, resulting in a size mismatch between the pore and the gas molecule. Recently, an ionic liquid (IL) which has a low volatility, is non-toxic, and has high chemical thermal stability, [33][34][35][36] was adopted to form 2D material supported IL membrane for CO 2 separation, and which exhibits an outstanding CO 2 separation capability, which largely surpasses most of the previously reported CO 2 separation membranes.…”