Related Experiment Video
Updated: May 11, 2025

A Protocol for Functional Assessment of Whole-Protein Saturation Mutagenesis Libraries Utilizing High-Throughput Sequencing
Published on: July 3, 2016
Structural Analysis and Mutability Landscape-Guided Engineering of ω-Transaminase for Improved Catalytic Performance
Puhong Yi1,2,3, Yue Xu1,2,3, Yuhua Hao1,2,3
1The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
Abstract:
ω-Transaminases (ω-TAs) are attractive biocatalysts in the asymmetric synthesis of chiral amines. Recently, a promising ω-TA from Salmonella enterica (SeTA) has been used to produce the valuable herbicide l-phosphinothricin (l-PPT). To improve the catalytic activity of SeTA, a combination strategy involving structural analysis and mutability landscape construction was conducted. A flexible region (loop1) enhancing the catalytic activity of SeTA was identified, and a distal mutant I22D (M1) was successfully screened. M1 showed a 3.24-fold increase in specific activity, along with greater thermal stability. Its half-life (t1/2) was 30.95-fold (45 °C) and 17.53-fold (55 °C) longer than that of WT, and Tm increased by 7.6 °C. MD simulations revealed that the distal mutation induced long-range effects through allostery, resulting in the substrate tunnel being more spacious, reshaping the active pocket, and stabilizing the local conformation. These findings can provide insights into the distal sites and functional relationships of ω-TAs for improving their performance.
Related Concept Videos
Catalytically Perfect Enzymes
Most enzymes...
Introduction to Mechanisms of Enzyme Catalysis
Chemiosmosis
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons...
Turnover Number and Catalytic Efficiency
Chymotrypsin is a pancreatic enzyme that breaks down proteins during digestion....
Allosteric Proteins-ATCase
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis...
ATP Synthase: Mechanism

