One-Step Purification and Immobilization of Glycosyltransferase with Zn–Ni MOF for the Synthesis of Rare Ginsenoside Rh2

Abstract

Uridine diphosphate (UDP)-glucosyltransferases (UGTs) have received increasing attention in the field of ginsenoside Rh2 conversion. By harnessing the metal chelation between transition metal ions and imidazole groups present on Histagged enzymes, a specific immobilization of the enzyme within metal−organic frameworks (MOFs) is achieved. This innovative approach not only enhances the stability and reusability of the enzyme but also enables one-step purification and immobilization. Consequently, the need for purifying crude enzyme solutions is effectively circumvented, resulting in significant cost savings during experimentation. The use of immobilized enzymes in catalytic reactions has shown great potential for achieving higher conversion rates of ginsenoside Rh2. In this study, highly stable mesoporous Zn−Ni MOF materials were synthesized at 150 °C by a solvothermal method. The UGT immobilized on the Zn−Ni MOF (referred to as UGT@Zn−Ni MOF) exhibited superior pH adaptability and thermal stability, retaining approximately 76% of its initial activity even after undergoing 7 cycles. Furthermore, the relative activity of the immobilized enzyme remained at an impressive 80.22% even after 45 days of storage. The strong specific adsorption property of Zn−Ni MOF on His-tagged UGT was confirmed through analysis using polyacrylamide gel electrophoresis. UGT@Zn−Ni MOF was used to catalyze the conversion reaction, and the concentration of rare ginsenoside Rh2 was generated at 3.15 μg/mL. The results showed that Zn−Ni MOF is a material that can efficiently purify and immobilize His-tagged enzyme in one step and has great potential for industrial applications in enzyme purification and ginsenoside synthesis.

Optimization of Interfacial Properties Improved the Stability and Activity of the Catalase Enzyme Immobilized on Plastic Nanobeads

“…Nanoparticles are excellent candidates as support matrices, as they provide high a surface area, efficient enzyme loading, and improved catalytic activity. − Moreover, the unique physicochemical properties of nanoparticles, such as size, shape, and surface chemistry, can be tailored to optimize the immobilization process and enhance the stability of immobilized enzymes. For instance, several studies have investigated the immobilization of CAT on various types of nanoparticles and their composites.…”