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Title: Rotational spectrum of tryptophan

Abstract

The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the {sup 14}N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O–H···N hydrogen bond in the side chain and a N–H···π interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.

Authors:
; ; ;  [1]
  1. Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Laboratorios de Espectroscopia y Bioespectroscopia, Unidad Asociada CSIC, Parque Científico Uva, Universidad de Valladolid, 47011 Valladolid (Spain)
Publication Date:
OSTI Identifier:
22304396
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 140; Journal Issue: 20; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; COUPLING CONSTANTS; FOURIER TRANSFORMATION; HYDROGEN; INTERACTIONS; MICROWAVE RADIATION; MOLECULAR BEAMS; SPECTRA; SPECTROSCOPY; TRYPTOPHAN

Citation Formats

Sanz, M. Eugenia, E-mail: maria.sanz@kcl.ac.uk, Cabezas, Carlos, E-mail: ccabezas@qf.uva.es, Mata, Santiago, E-mail: santiago.mata@uva.es, and Alonso, Josè L., E-mail: jlalonso@qf.uva.es. Rotational spectrum of tryptophan. United States: N. p., 2014. Web. doi:10.1063/1.4876001.
Sanz, M. Eugenia, E-mail: maria.sanz@kcl.ac.uk, Cabezas, Carlos, E-mail: ccabezas@qf.uva.es, Mata, Santiago, E-mail: santiago.mata@uva.es, & Alonso, Josè L., E-mail: jlalonso@qf.uva.es. Rotational spectrum of tryptophan. United States. doi:10.1063/1.4876001.
Sanz, M. Eugenia, E-mail: maria.sanz@kcl.ac.uk, Cabezas, Carlos, E-mail: ccabezas@qf.uva.es, Mata, Santiago, E-mail: santiago.mata@uva.es, and Alonso, Josè L., E-mail: jlalonso@qf.uva.es. Wed . "Rotational spectrum of tryptophan". United States. doi:10.1063/1.4876001.
@article{osti_22304396,
title = {Rotational spectrum of tryptophan},
author = {Sanz, M. Eugenia, E-mail: maria.sanz@kcl.ac.uk and Cabezas, Carlos, E-mail: ccabezas@qf.uva.es and Mata, Santiago, E-mail: santiago.mata@uva.es and Alonso, Josè L., E-mail: jlalonso@qf.uva.es},
abstractNote = {The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the {sup 14}N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O–H···N hydrogen bond in the side chain and a N–H···π interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.},
doi = {10.1063/1.4876001},
journal = {Journal of Chemical Physics},
number = 20,
volume = 140,
place = {United States},
year = {Wed May 28 00:00:00 EDT 2014},
month = {Wed May 28 00:00:00 EDT 2014}
}
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