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Helix formation via conformation diffusion search.

Cheng-Yen Huang·Zelleka Getahun·Yongjin Zhu·Jason W Klemke·William F DeGrado·Feng Gai
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Abstract

The helix-coil transition kinetics of an alpha-helical peptide were investigated by time-resolved infrared spectroscopy coupled with laser-induced temperature-jump initiation method. Specific isotope labeling of the amide carbonyl groups with 13C at selected residues was used to obtain site-specific information. The relaxation kinetics following a temperature jump, obtained by probing the amide I' band of the peptide backbone, exhibit nonexponential behavior and are sensitive to both initial and final temperatures. These data are consistent with a conformation diffusion process on the folding energy landscape, in accord with a recent molecular dynamics simulation study.

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Computer SimulationDiffusionModels, MolecularPeptidesProtein ConformationSpectroscopy, Fourier Transform InfraredJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Cheng-Yen Huang, Zelleka Getahun, Yongjin Zhu, Jason W Klemke, William F DeGrado, Feng Gai. 2002-02-26. Helix formation via conformation diffusion search.. https://doi.org/10.1073/pnas.052700099

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