The present paper reports the experimental observation of an interesting thermodynamic process which could be biologically important: such behaviour, shown by some gangliosides, is likely to be peculiar of these glycosidic compounds as if has never been observed for other membrane-type amphiphilic molecules. In water solution, gangliosides have been found to present a bistable behaviour between two stable states (called A and B) which does not involve any change in the primary structure of the molecule. The interconversion between state A and state B, and vice versa, does not occur spontaneously, but has to be triggered by some external agent, which makes this system a potentially regulated process with important biological correlations. In the present experiments, state B is reached from state A with a temperature rise in the range 30-55 degrees C. The new state is stable regardless of any possible temperature cycle. The initial state A is then regained when the ganglioside solution is dried and the solute is redissolved. The two states are believed to correspond to two different conformations of the hydrophilic portion of the molecule. The bistable behaviour is shown by the gangliosides GM2, GM1, GD1a, GD1b and Fuc-GD1b. GT1b, however, does not show such an effect

Experimental evidence of a temperature-related conformational change of the hydrophilic portion of gangliosides / L. Cantù, M. Corti, E. Del Favero, E. Digirolamo, S. Sonnino, G. Tettamanti. - In: CHEMISTRY AND PHYSICS OF LIPIDS. - ISSN 0009-3084. - 79:2(1996 Sep 29), pp. 137-145. [10.1016/0009-3084(96)02521-2]

Experimental evidence of a temperature-related conformational change of the hydrophilic portion of gangliosides

L. Cantù;M. Corti;E. Del Favero;S. Sonnino;G. Tettamanti
1996-09-29

Abstract

The present paper reports the experimental observation of an interesting thermodynamic process which could be biologically important: such behaviour, shown by some gangliosides, is likely to be peculiar of these glycosidic compounds as if has never been observed for other membrane-type amphiphilic molecules. In water solution, gangliosides have been found to present a bistable behaviour between two stable states (called A and B) which does not involve any change in the primary structure of the molecule. The interconversion between state A and state B, and vice versa, does not occur spontaneously, but has to be triggered by some external agent, which makes this system a potentially regulated process with important biological correlations. In the present experiments, state B is reached from state A with a temperature rise in the range 30-55 degrees C. The new state is stable regardless of any possible temperature cycle. The initial state A is then regained when the ganglioside solution is dried and the solute is redissolved. The two states are believed to correspond to two different conformations of the hydrophilic portion of the molecule. The bistable behaviour is shown by the gangliosides GM2, GM1, GD1a, GD1b and Fuc-GD1b. GT1b, however, does not show such an effect
micelles ; glycosphingolipids ; light scattering
Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)
Article (author)
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2434/20137
Citazioni
  • ???jsp.display-item.citation.pmc??? 1
  • Scopus 35
  • ???jsp.display-item.citation.isi??? ND
social impact