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Tryptophan rotamers as evidenced by X-ray, fluorescence lifetimes, and molecular dynamics modeling.

ABSTRACT: We investigated the native-state dynamics of the Bacillus caldolyticus cold-shock protein mutant Bc-Csp L66E, using fluorescence and appropriate molecular dynamics methods. Two fluorescence lifetimes were found, the amplitudes of which agree very well with tryptophan rotamer populations, obtained from parallel tempering calculations. Rotamer lifetimes were predicted by transition-state theory from high-temperature simulations. Transition pathways were extracted from the transition rates between individual rotameric states. The molecular dynamics also reveal the loop fluctuations in the native state.

SUBMITTER: Moors SL

PROVIDER: S-EPMC1563760 | biostudies-literature | 2006 Aug

REPOSITORIES: biostudies-literature

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Tryptophan rotamers as evidenced by X-ray, fluorescence lifetimes, and molecular dynamics modeling.

Moors Samuel L C SL Hellings Mario M De Maeyer Marc M Engelborghs Yves Y Ceulemans Arnout A

Biophysical journal 20060512 3

We investigated the native-state dynamics of the Bacillus caldolyticus cold-shock protein mutant Bc-Csp L66E, using fluorescence and appropriate molecular dynamics methods. Two fluorescence lifetimes were found, the amplitudes of which agree very well with tryptophan rotamer populations, obtained from parallel tempering calculations. Rotamer lifetimes were predicted by transition-state theory from high-temperature simulations. Transition pathways were extracted from the transition rates between ...[more]

PMID: 16698786

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