Ion mobility spectrometry, infrared dissociation spectroscopy, and ab initio computations toward structural characterization of the deprotonated leucine-enkephalin peptide anion in the gas phase.
J Phys Chem A
; 118(37): 8453-63, 2014 Sep 18.
Article
em En
| MEDLINE
| ID: mdl-24884600
ABSTRACT
Although the sequencing of protonated proteins and peptides with tandem mass spectrometry has blossomed into a powerful means of characterizing the proteome, much less effort has been directed at their deprotonated analogues, which can offer complementary sequence information. We present a unified approach to characterize the structure and intermolecular interactions present in the gas-phase pentapeptide leucine-enkephalin anion by several vibrational spectroscopy schemes as well as by ion-mobility spectrometry, all of which are analyzed with the help of quantum-chemical computations. The picture emerging from this study is that deprotonation takes place at the C terminus. In this configuration, the excess charge is stabilized by strong intramolecular hydrogen bonds to two backbone amide groups and thus provides a detailed picture of a potentially common charge accommodation motif in peptide anions.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fragmentos de Peptídeos
/
Prótons
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Teoria Quântica
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Encefalina Leucina
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Gases
Idioma:
En
Revista:
J Phys Chem A
Ano de publicação:
2014
Tipo de documento:
Article