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Updated: Aug 11, 2026
06:16
High Throughput Screening of Fungal Endoglucanase Activity in Escherichia coli
Published on: August 13, 2011
Substrate binding interferes with active site conformational dynamics in endoglucanase Cel5A from Thermobifida fusca
Xukai Jiang1, Yuying Wang1, Limei Xu2
1State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100, PR China.
Biochemical and Biophysical Research Communications
|July 20, 2017
Summary
Protein dynamics are key to enzyme catalysis. Molecular simulations reveal endoglucanase Cel5A uses a hybrid mechanism, combining conformational selection and induced fit for substrate binding, offering insights for protein engineering.
Area of Science:
- Enzymology and structural biology
- Computational biophysics
Background:
- Protein dynamics play a crucial role in enzyme catalysis.
- Understanding enzyme-substrate interactions is vital for enzymology.
Purpose of the Study:
- To investigate the dynamic behavior of endoglucanase Cel5A (TfCel5A) upon substrate binding using molecular dynamics simulations.
- To elucidate the mechanism of substrate binding and active site conformational changes in TfCel5A.
Main Methods:
- Molecular dynamics (MD) simulations were employed.
- Analysis of collective motions and conformational ensembles of active site residues.
Main Results:
- TfCel5A substrate binding follows a hybrid mechanism involving both conformational selection and induced fit.
- Specific active site residues (Tyr163, Glu355) adopted new conformations, while others (Phe162, Tyr189) shifted their conformational distributions.
- Enzyme active site conformational rebalancing after substrate dissociation was slower than substrate binding.
Conclusions:
- The study reveals a nuanced mechanism for TfCel5A substrate binding, integrating conformational selection and induced fit.
- Protein dynamics significantly influence enzyme catalysis, with implications for protein engineering.
- Conformational changes during substrate binding and dissociation exhibit distinct kinetic profiles.
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