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Related Experiment Video

Updated: Jan 3, 2026

Multi-enzyme Screening Using a High-throughput Genetic Enzyme Screening System

Multi-enzyme Screening Using a High-throughput Genetic Enzyme Screening System

Published on: August 8, 2016

Engineering Protease-Resistant and Highly Active Phytases.

Canfang Niu¹, Peilong Yang², Bin Yao²

¹Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China. niucanfang@163.com.

Methods in Molecular Biology (Clifton, N.J.)

|November 28, 2019

Summary

Genetic engineering improves phytase enzyme stability against digestive proteases and low pH. This optimization enhances the enzyme

Keywords:

HAP phytase High activity Low PH Optimizing the residual side chain Pepsin resistance Trypsin resistance

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Published on: November 23, 2019

Area of Science:

Enzymology and Biotechnology
Protein Engineering
Microbial Biochemistry

Background:

Phytases are crucial enzymes that hydrolyze phytate, releasing essential phosphorus.
Enzyme stability against proteases and pH is vital for industrial and therapeutic applications.
The HAP phytase YeAPPA from Yersinia enterocolitica is sensitive to pepsin, trypsin, and low pH.

Purpose of the Study:

To develop a genetic manipulation strategy for enhancing phytase YeAPPA tolerance.
To improve enzyme resistance to specific proteases (pepsin, trypsin) and acidic conditions.
To optimize the enzyme's residual side chain for increased stability.

Main Methods:

Genetic engineering of Yersinia enterocolitica HAP phytase YeAPPA.
Site-directed mutagenesis focusing on residual side chain optimization.
Enzyme activity and stability assays under varying pH and protease concentrations.

Main Results:

Successfully improved phytase YeAPPA tolerance to pepsin, trypsin, and low pH.
Identified specific residual side chain modifications that confer enhanced stability.
Demonstrated the feasibility of targeted genetic manipulation for enzyme improvement.

Conclusions:

Optimized phytase YeAPPA exhibits superior resistance to digestive proteases and acidic environments.
This engineered phytase has potential for broader biotechnological and medical applications.
The described genetic method offers a pathway for developing more robust industrial enzymes.