Inhibition of the urea-urease reaction by the components of the zeolite imidazole frameworks-8 and the formation of urease-zinc-imidazole hybrid compound

Abstract

In the past decade, much effort has been devoted to using chemical clock-type reactions in material design and driving the self-assembly of various building blocks. Urea-urease enzymatic reaction has chemical pH clock behavior in an unbuffered medium, in which the induction time and the final pH can be programmed by the concentrations of the reagents. The urea-urease reaction can offer a new alternative in material synthesis, where the pH and its course in time are crucial factors in the synthesis. However, before using it in any synthesis method, it is important to investigate the possible effects of the reagents on the enzymatic reaction. Here we investigate the effect of the reagents of the zeolite imidazole framework-8 (zinc ions and 2-methylimidazole) on the urea-urease reaction. We have chosen the zeolite imidazole framework-8 because its formation serves as a model reaction for the formation of other metal–organic frameworks. We found that, besides the inhibition effect of the zinc ions which is well-known in the literature, 2-methylimidazole inhibits the enzymatic reaction as well. In addition to the observed inhibition effect, we report the formation of a hybrid urease-zinc-2-methylimidazole hybrid material. To support the inhibition effect, we developed a kinetic model which reproduced qualitatively the experimentally observed kinetic curves.

Nanomaterials for Potential Detection and Remediation: A Review of Their Analytical and Environmental Applications

“…It is well known that phosphorodiamidates and imidazole are typical mechanism-based inhibitors of urease. Phosphorodiamidates have a P=O bond that tends to interact with the Ni ion in the active center of urease, further decreasing urea's binding to urease, leading to inhibition of urease activity [113,114]. Glyphosate (OH 2 -PO-NH-COOH), being structurally similar to phosphorodiamidates (OH 2 -PO-NH-R), may exhibit the inhibition of urease by a similar mechanism.…”

The role of protein folding in prenucleation clusters on the activity of enzyme@metal–organic frameworks

“…Other studies have shown that hydrophilic ligands can stabilize enzymes in their active conformation, retaining activity of the enzyme in the final enzyme@MOF, 18 whereas more hydrophobic ligands lead to a loss of functionality. 19 Thus, a more comprehensive understanding of biomolecular folding during enzyme@MOF synthesis is needed. Here, we reemphasize the role of MOF crystallinity in enzyme@ZIF-8 activity, while introducing a novel factor relevant to activity: enzymatic interactions with MOF building blocks.…”

Application of a chemical clock in material design: chemically programmed synthesis of zeolitic imidazole framework-8

“…, oxidative) initial reagents and intermediate products that may interfere with the building blocks limiting the applicability of these autonomous systems. 35 Therefore, the application of autonomous chemical reactions in materials synthesis and design remains challenging. However, the application of these reactions may provide two very important benefits for the synthesis.…”