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PubMed · 10430896

Understanding beta-hairpin formation.

A R Dinner·T Lazaridis·M Karplus
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Abstract

The kinetics of formation of protein structural motifs (e.g., alpha-helices and beta-hairpins) can provide information about the early events in protein folding. A recent study has used fluorescence measurements to monitor the folding thermodynamics and kinetics of a 16-residue beta-hairpin. In the present paper, we obtain the free energy surface and conformations involved in the folding of an atomistic model for the beta-hairpin from multicanonical Monte Carlo simulations. The results suggest that folding proceeds by a collapse that is downhill in free energy, followed by rearrangement to form a structure with part of the hydrophobic cluster; the hairpin hydrogen bonds propagate outwards in both directions from the partial cluster. Such a folding mechanism differs from the published interpretation of the experimental results, which is based on a helix-coil-type phenomenological model.

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Amino Acid SequenceCalorimetryComputer GraphicsKineticsModels, MolecularMolecular Sequence DataPeptidesProtein ConformationProtein Structure, SecondaryProteinsSoftwareThermodynamicsJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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A R Dinner, T Lazaridis, M Karplus. 1999-08-03. Understanding beta-hairpin formation.. https://doi.org/10.1073/pnas.96.16.9068

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