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Two-Dimensional Infrared (2DIR) Spectroscopy of the Peptide Beta3s Folding.

ABSTRACT: Probing underlying free energy landscape, pathways, and mechanism is the key for understanding protein folding in theory and experiment. Recently time-resolved two-dimensional infrared (2DIR) with femtosecond laser pulses, has emerged as a promising tool for investigating the protein folding dynamics on faster timescales than possible by NMR. We have employed molecular dynamics simulations to compute 2DIR spectra of the folding process of a peptide, Beta3s. Simulated non-chiral and chiral 2DIR signals illustrate the variation of the spectra as the peptide conformation evolves along the free energy landscape. Chiral spectra show stronger changes than the non-chiral signals because cross peaks caused by the formation of the ?-sheet are clearly resolved. Chirality-induced 2DIR may be used to detect the folding of ?-sheet proteins with high spectral and temporal resolution.

SUBMITTER: Lai Z

PROVIDER: S-EPMC3744343 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Two-Dimensional Infrared (2DIR) Spectroscopy of the Peptide Beta3s Folding.

Lai Zaizhi Z Preketes Nicholas K NK Jiang Jun J Mukamel Shaul S Wang Jin J

The journal of physical chemistry letters 20130601 11

Probing underlying free energy landscape, pathways, and mechanism is the key for understanding protein folding in theory and experiment. Recently time-resolved two-dimensional infrared (2DIR) with femtosecond laser pulses, has emerged as a promising tool for investigating the protein folding dynamics on faster timescales than possible by NMR. We have employed molecular dynamics simulations to compute 2DIR spectra of the folding process of a peptide, Beta3s. Simulated non-chiral and chiral 2DIR s ...[more]

PMID: 23956818

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