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Updated: Jul 3, 2026
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Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions
Published on: April 4, 2014
[Research on the orientedly immobilized urease via concanavalin A]
Jianqin Zhou1, Shaohua Chen, Jianwen Wang
1School of Pharmacy, Soochow University, Suzhou 215123, China. zkzhu@ustc.edu
Summary
Oriented immobilization of urease on Concanavalin A-activated chitosan microspheres enhances enzyme stability and substrate affinity. This method improves urease performance, offering a stable and efficient biocatalyst for various applications.
Area of Science:
- Biochemistry
- Biomaterials Science
- Enzyme Engineering
Context:
- Enzyme immobilization is crucial for industrial biocatalysis.
- Chitosan microspheres offer a biocompatible and versatile matrix.
- Concanavalin A (ConA) facilitates specific protein binding via glycoprotein interactions.
Purpose:
- To achieve oriented immobilization of urease using ConA-activated chitosan microspheres.
- To optimize immobilization conditions for enhanced enzyme activity and stability.
- To characterize the kinetic and operational properties of the oriented immobilized urease.
Summary:
- Urease was oriented and immobilized onto ConA-activated chitosan microspheres.
- Optimal conditions involved 3.5% glutaraldehyde, 1 mg/mL ConA at pH 7.0, and 0.4 mg/mL urease.
- The immobilized urease exhibited optimal activity at pH 5.0-6.0 and 77°C, with a Km of 11.76 mmol/L.
- Oriented immobilization resulted in a narrower optimal pH range but a wider pH domain, increased temperature resistance, higher substrate affinity, and improved operational stability compared to free or randomly immobilized urease.
Impact:
- Provides a robust method for oriented enzyme immobilization.
- Enhances enzyme stability, affinity, and operational performance.
- Offers a promising biocatalyst for applications requiring high urease activity and stability.
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01:33Enzyme-Linked Immunosorbent Assay
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