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Updated: Jun 25, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Electronic structure of 5-hydroxyindole: from gas phase to explicit solvation
David Robinson1, Nicholas A Besley, Elizabeth A M Lunt
1School of Chemistry, and Cell Biophysics Group, School of Biology, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
The Journal of Physical Chemistry. B
|February 7, 2009
Summary
We studied 5-hydroxyindole
Area of Science:
- Computational chemistry
- Spectroscopy
- Biophysics
Background:
- 5-Hydroxyindole is the fluorophore of 5-hydroxytryptophan, a non-natural amino acid.
- 5-Hydroxytryptophan is an emerging intrinsic probe for protein analysis.
- Understanding 5-hydroxyindole's spectral properties is crucial for its application.
Purpose of the Study:
- To investigate the absorption and emission spectrum of 5-hydroxyindole.
- To elucidate the role of solvent effects and hydrogen bonding on spectral properties.
- To provide insights into the use of 5-hydroxytryptophan as a protein probe.
Main Methods:
- Gas-phase and implicit solvent calculations using multiconfigurational perturbation theory (CASPT2).
- Explicit solvent model calculations employing a decoupled quantum mechanics/molecular mechanics approach.
- Utilizing recent advances in time-dependent density functional theory for solvent modeling.
Main Results:
- Calculated absorption and emission spectra of 5-hydroxyindole in gas and solvent phases.
- Demonstrated the significant impact of hydrogen bonding on spectral characteristics.
- Observed the 1L(b) state at lower energy than the 1L(a) state, with 1L(a) as the emitting state.
Conclusions:
- Hydrogen bonding plays a critical role in modulating 5-hydroxyindole's spectral behavior.
- The findings support the utility of 5-hydroxytryptophan as a sensitive probe in biophysical studies.
- Accurate spectral characterization is essential for interpreting experimental data involving 5-hydroxyindole.
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