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Levinthal's question revisited, and answered
1Department of Physical Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel. arieh@fh.huji.ac.il
Journal of Biomolecular Structure & Dynamics
|May 11, 2012
Summary
The protein-folding problem remains unsolved due to misinterpretations of thermodynamic principles and overemphasis on hydrophobic effects. A shift to a cause-based, hydrophilic approach offers a straightforward solution to protein folding.
Area of Science:
- Biochemistry
- Molecular Biology
- Structural Biology
Background:
- The Levinthal paradox highlights the immense time proteins would take to fold randomly.
- The protein-folding problem (PFP) has been a long-standing challenge in molecular biology.
- Previous approaches often misinterpreted Anfinsen's thermodynamic hypothesis and overlooked hydrophilic interactions.
Purpose of the Study:
- To re-evaluate the reasons behind the elusiveness of the protein-folding problem.
- To propose a new paradigm for understanding and solving protein folding.
- To address the Levinthal question regarding the unique structure of folded proteins.
Main Methods:
- Critical analysis of existing interpretations of Anfinsen's thermodynamic hypothesis.
- Examination of the limitations of the hydrophobic paradigm in protein folding.
- Advocacy for a shift from target-based to cause-based approaches.
- Emphasis on the role of hydrophilic effects in protein folding.
Main Results:
- Misinterpretation of Gibbs energy minima and overreliance on the hydrophobic paradigm have hindered PFP solutions.
- Ignoring hydrophilic effects has obscured a simpler understanding of protein folding.
- A cause-based approach incorporating hydrophilic interactions provides a direct solution.
Conclusions:
- The protein-folding problem can be solved by adopting a cause-based approach.
- Understanding and integrating hydrophilic effects are crucial for solving PFP.
- A revised perspective on thermodynamic principles simplifies the answer to Levinthal's question.
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