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Updated: Jun 22, 2025
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Dual-Color Fluorescence Cross-Correlation Spectroscopy to Study Protein-Protein Interaction and Protein Dynamics in Live Cells
Published on: December 11, 2021
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Statistical Coupling Analysis Predicts Correlated Motions in Dihydrofolate Reductase
Thomas L Kalmer1, Christine Mae F Ancajas1, Cameron I Cohen2,3
1Department of Chemistry, Vanderbilt University Nashville, TN, USA.
Biorxiv : the Preprint Server for Biology
|July 1, 2024
Summary
Protein dynamics significantly influence enzyme evolution. This study reveals how coupled motions in dihydrofolate reductase (DHFR) affect its evolutionary trajectory, with implications for protein engineering.
Area of Science:
- Enzymology and Molecular Evolution
- Protein Dynamics and Allostery
Background:
- Dihydrofolate reductase (DHFR) is a crucial enzyme and a model system for studying enzyme dynamics.
- The relationship between protein dynamics, residue networks, and enzyme evolution remains incompletely understood.
- Previous research identified specific mutations affecting DHFR dynamics and catalysis, but their evolutionary impact is unclear.
Purpose of the Study:
- To investigate the role of dynamically coupled residue networks in the evolution of DHFR.
- To determine if allosteric communication within these networks is essential for evolutionary adaptation.
- To identify potential sites in human DHFR for mutations that preserve dynamics.
Main Methods:
- Statistical coupling analysis to identify coevolving residue networks.
- Molecular dynamics simulations to analyze correlated motions and allosteric communication.
- Site-directed mutagenesis (N23PP/S148A) in E. coli DHFR to assess the impact on dynamics and allostery.
Main Results:
- A network of coevolving residues with correlated motions was identified in DHFR.
- Allosteric communication within this network was significantly disrupted by the N23PP/S148A mutation.
- Two potential sites in human DHFR were identified that could tolerate similar mutations while maintaining protein dynamics.
Conclusions:
- Protein dynamics are a significant driving force in enzyme evolution.
- Dynamically coupled networks and their allosteric communication are critical for evolutionary adaptation.
- Understanding these dynamics can guide protein engineering efforts for enzymes like DHFR.
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