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Updated: Jun 16, 2026
04:37
High-Pressure NMR Experiments for Detecting Protein Low-Lying Conformational States
Published on: June 29, 2021
Dynamic correlation between pressure-induced protein structural transition and water penetration
1Computational Science Research Program and Advanced Science Institute, RIKEN, Wako, Saitama 351-0112, Japan. takashi.imai@riken.jp
The Journal of Physical Chemistry. B
|January 27, 2010
Summary
High pressure causes water to penetrate proteins, driving denaturation. This study provides direct evidence of water penetration into ubiquitin
Area of Science:
- Biophysics
- Structural Biology
- Computational Chemistry
Background:
- Protein denaturation under high pressure is a critical phenomenon.
- Water penetration into protein hydrophobic cores is a proposed mechanism for pressure-induced denaturation.
- Direct experimental evidence for this water penetration model is limited.
Purpose of the Study:
- To investigate the water penetration model for pressure-induced protein denaturation.
- To examine the behavior of ubiquitin under high pressure using molecular dynamics simulations.
Main Methods:
- All-atom molecular dynamics simulations of ubiquitin in explicit water.
- Simulations conducted at both high and low pressure conditions.
- Analysis of structural transitions and water penetration dynamics.
Main Results:
- High pressure successfully induced structural changes in ubiquitin, consistent with experimental data.
- Water was observed to penetrate a specific hydrophobic core of ubiquitin.
- The protein underwent cycles of water penetration and ejection, leading to structural transitions.
- Simultaneous water penetration was observed only above a specific high pressure threshold.
Conclusions:
- The study provides direct evidence supporting the water penetration model for pressure-induced protein denaturation.
- Pressure stabilizes a pre-existing metastable protein structure, facilitating water entry.
- Water penetration occurs on a timescale comparable to water's own relaxation time.
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