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Updated: Jan 31, 2026
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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
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Conformational selection turns on phenylalanine hydroxylase.
Kirill A Konovalov1, Wei Wang1, Xuhui Huang2
1From the Department of Chemistry, Center of Systems Biology and Human Health, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
The Journal of Biological Chemistry
|December 23, 2018
Summary
Phenylalanine hydroxylase (PAH) regulates phenylalanine metabolism. Simulations reveal protein gating motions, suggesting a conformational selection mechanism for allosteric activation by phenylalanine.
Area of Science:
- Biochemistry
- Enzymology
- Protein dynamics
Background:
- Phenylalanine hydroxylase (PAH) is crucial for phenylalanine catabolism.
- Enzyme dysfunction causes phenylketonuria.
- Phenylalanine acts as a positive allosteric regulator of PAH.
Discussion:
- The allosteric binding site of PAH has been structurally characterized.
- The precise mechanism of allosteric activation by phenylalanine remains elusive.
- Large-scale simulations were employed to investigate phenylalanine binding to the regulatory site.
Key Insights:
- Ge et al. discovered protein gating motions during phenylalanine binding.
- These motions suggest a conformational selection mechanism for allosteric activation.
- This finding provides new insights into PAH regulation.
Outlook:
- Further research can elucidate the dynamics of conformational selection.
- Understanding PAH regulation may lead to novel therapeutic strategies for phenylketonuria.
- Computational approaches can be valuable for studying enzyme mechanisms.
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