23Na NMR study of the effect of organic osmolytes on DNA counterion atmosphere.
Biophys J
; 71(3): 1519-29, 1996 Sep.
Article
em En
| MEDLINE
| ID: mdl-8874025
ABSTRACT
The effect of different organic osmolytes on the DNA counterion condensation layer has been investigated by 23Na NMR relaxation measurements. The zwitterionic compounds glycine, beta-alanine, 4-aminobutyric acid, and 6-aminocaproic acid have shown an increasing capacity to decrease the amount of sodium ions in the vicinity of the macromolecule. The experimental data have been correlated with the dielectric constant increase in their corresponding solutions and have been compared with the prediction of counterion condensation theory. Polyols (sorbitol and mannitol) did not display the same effect. These compounds largely increase the relaxation rate of sodium ions in the proximity of DNA, unlike the zwitterionic compounds. This probably results from a perturbation of the water dynamic around the macromolecule, of the primary or secondary hydration shell of the sodium nuclei involved, or both.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
DNA
Limite:
Animals
Idioma:
En
Revista:
Biophys J
Ano de publicação:
1996
Tipo de documento:
Article
País de afiliação:
Bélgica