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Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
How general is the nucleation-condensation mechanism?
1Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158-2517, USA.
Proteins
|May 24, 2008
Summary
Small globular proteins predominantly fold via a nucleation-condensation mechanism. This process involves concurrent secondary and tertiary structure formation, with a single folding nucleus driving consolidation.
Area of Science:
- Protein folding dynamics
- Biophysics
- Structural biology
Background:
- Understanding protein folding mechanisms is crucial for deciphering biological functions.
- Previous models like hydrophobic collapse and zipper mechanisms offer partial explanations.
- The nucleation-condensation mechanism proposes a specific pathway for protein folding.
Purpose of the Study:
- To investigate the folding transition states of nine proteins.
- To correlate published Phi-values with inter-residue contact maps.
- To synthesize findings into a unified nucleation-condensation model.
Main Methods:
- Analysis of published Phi-values.
- Correlation with inter-residue contact maps.
- Comparative analysis across 15 small globular proteins.
Main Results:
- At least 10 of 15 proteins studied fold via nucleation-condensation.
- Folding consolidation is nonuniform, with a single dominant nucleus.
- Helix- and sheet-forming residues exhibit higher Phi-values, indicating their role in nuclei.
Conclusions:
- A unified nucleation-condensation mechanism explains protein folding.
- Secondary structure formation is a key driving force in nucleation.
- This model integrates aspects of framework, hydrophobic collapse, zipper, and funnel models.
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