Changes in water structure induced by the guanidinium cation and implications for protein denaturation.
J Phys Chem A
; 112(43): 10939-48, 2008 Oct 30.
Article
em En
| MEDLINE
| ID: mdl-18839935
ABSTRACT
The effect of the guanidinium cation on the hydrogen bonding strength of water was analyzed using temperature-excursion Fourier transform infrared spectra of the OH stretching vibration in 5% H 2O/95% D 2O solutions containing a range of different guanidine-HCl and guanidine-HBr concentrations. Our findings indicate that the guanidinium cation causes the water H-bonds in solution to become more linear than those found in bulk water, and that it also inhibits the response of the H-bond network to increased temperature. Quantum chemical calculations also reveal that guanidinium affects both the charge distribution on water molecules directly H-bonded to it as well as the OH stretch frequency of H-bonds in which that water molecule is the donor. The implications of our findings to hydrophobic solvation and protein denaturation are discussed.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Água
/
Proteínas
/
Guanidina
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
J Phys Chem A
Assunto da revista:
QUIMICA
Ano de publicação:
2008
Tipo de documento:
Article