Related Experiment Video
Updated: Aug 11, 2026
06:48
Single-Molecule Measurement of Protein Interaction Dynamics Within Biomolecular Condensates
Published on: January 5, 2024
Structural transitions of confined model proteins: molecular dynamics simulation and experimental validation
Diannan Lu1, Zheng Liu, Jianzhong Wu
1Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Biophysical Journal
|February 8, 2006
Summary
Protein folding in confined spaces is influenced by cage size and hydrophobicity. Moderate confinement optimizes protein folding yield and kinetics, as supported by hen-egg lysozyme refolding experiments.
Area of Science:
- Biophysics
- Computational Biology
- Protein Science
Background:
- Protein folding occurs in vivo within crowded cellular environments and in vitro during recombinant protein production.
- The impact of confinement on protein folding thermodynamics and kinetics remains largely unexplored.
- Understanding confined protein folding is crucial for biotechnology and cellular biology.
Purpose of the Study:
- To investigate the effects of confinement size and surface hydrophobicity on protein folding and stability.
- To explore the mechanisms by which confinement influences protein folding kinetics and thermodynamics.
- To validate simulation findings with experimental refolding studies of hen-egg lysozyme.
Main Methods:
- Utilized a Gō-like off-lattice model for coarse-grained simulations of protein folding in spherical cages.
- Varied cage size and surface hydrophobicity in simulations.
- Experimentally studied hen-egg lysozyme refolding using cetyltrimethylammoniumbromide (CTAB) micelles for confinement and beta-cyclodextrin-grafted-PNIPAAm for micelle disruption.
- Employed circular dichroism, fluorescence spectroscopy, and biological activity assays for experimental analysis.
Main Results:
- Extreme confinement inhibits correct protein folding.
- Hydrophilic cages stabilize proteins by restricting unfolded configurations.
- Hydrophobic cages destabilize proteins due to competition between self-aggregation and surface adsorption.
- Folding kinetics correlate strongly with cage size and hydrophobicity.
- Moderate-sized, moderately hydrophobic cages optimize folding yield and kinetics.
- CTAB micelles facilitate lysozyme collapse, while beta-cyclodextrin-grafted-PNIPAAm promotes activity recovery.
Conclusions:
- Confinement significantly alters protein folding pathways and stability.
- Cage properties (size, hydrophobicity) critically determine folding outcomes.
- Computational models accurately predict experimental observations of confined protein refolding.
- Tailoring confinement conditions can optimize protein folding and recovery for biotechnological applications.
