Charge-Induced Unzipping of Isolated Proteins to a Defined Secondary Structure.
Angew Chem Int Ed Engl
; 55(10): 3295-9, 2016 Mar 01.
Article
en En
| MEDLINE
| ID: mdl-26847383
Here we present a combined experimental and theoretical study on the secondary structure of isolated proteins as a function of charge state. In infrared spectra of the proteins ubiquitin and cytochromeâ
c, amideâ
I (C=O stretch) and amideâ
II (N-H bend) bands can be found at positions that are typical for condensed-phase proteins. For high charge states a new band appears, substantially red-shifted from the amideâ
II band observed at lower charge states. The observations are interpreted in terms of Coulomb-driven transitions in secondary structures from mostly helical to extended C5 -type hydrogen-bonded structures. Support for this interpretation comes from simple energy considerations as well as from quantum chemical calculations on model peptides. This transition in secondary structure is most likely universal for isolated proteins that occur in mass spectrometric experiments.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Ubiquitina
/
Citocromos c
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Año:
2016
Tipo del documento:
Article
País de afiliación:
Alemania