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Author Spotlight: Exploring Intrinsically Disordered Protein Dynamics Through NMR Relaxation Experiments
Published on: November 1, 2024
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Functional-State Dependence of Picosecond Protein Dynamics
D K George1, J Y Chen1, Yunfen He1
1Department of Physics, University at Buffalo, SUNY, Buffalo, New York 14260, United States.
The Journal of Physical Chemistry. B
|October 4, 2021
Summary
Protein dynamics reveal distinct temperature-dependent behaviors. A lower-energy process linked to collective motions disappears upon denaturing or ligand binding, highlighting structural flexibility in proteins like lysozyme and cytochrome c.
Area of Science:
- Biophysics
- Protein Dynamics
- Terahertz Spectroscopy
Background:
- Proteins exhibit complex dynamics crucial for function.
- Understanding these dynamics requires sensitive measurement techniques.
- Temperature significantly influences protein conformational changes.
Purpose of the Study:
- To investigate temperature-dependent picosecond dynamics of lysozyme and cytochrome c.
- To elucidate the nature of protein structural motions and their environmental dependencies.
- To correlate observed dynamics with protein structural integrity and ligand interactions.
Main Methods:
- Temperature-dependent terahertz permittivity measurements were employed.
- Analysis utilized a double Arrhenius model to fit the data.
- Comparison between folded, denatured, and ligand-bound protein states.
Main Results:
- A double Arrhenius temperature dependence was observed for folded proteins.
- Two distinct activation energies (E1 ≈ 0.1 kJ/mol, E2 ≈ 10 kJ/mol) were identified.
- The lower activation energy process, linked to correlated structural motions, was absent in denatured proteins and diminished with ligand binding.
Conclusions:
- The higher activation energy corresponds to the protein dynamical transition at the solvent-protein interface.
- The lower activation energy is attributed to collective structural motions sensitive to protein structure and ligand binding.
- These findings suggest that collective motions are essential for protein flexibility and are modulated by structural integrity and ligand interactions.
