The unfolding induced by guanidine hydrochloride of the small protein Sso7d from the hyperthermophilic archaeon Sulfolobus solfataricus has been investigated by means of circular dichroism and fluorescence measurements. At neutral pH and room temperature the midpoint of the transition occurred at 4 M guanidine hydrochloride. Thermodynamic information was obtained by means of both the linear extrapolation model and the denaturant binding model, in the assumption of a two-state N⇔D transition. A comparison with thermodynamic data determined from the thermal unfolding of Sso7d indicated that the denaturant binding model has to be preferred. Finally, it is shown that Sso7d is the most stable against both temperature and guanidine hydrochloride among a set of globular proteins possessing a very similar 3D structure. © 2004 Elsevier B.V. All rights reserved
Granata, V., Vecchio, P., Barone, G., Shehi, E., Fusi, P., Tortora, P., et al. (2004). Guanidine-induced unfolding of the Sso7d protein from the hyperthermophilic archaeon Sulfolobus solfataricus. INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES, 34(3), 195-201 [10.1016/j.ijbiomac.2004.04.002].
Guanidine-induced unfolding of the Sso7d protein from the hyperthermophilic archaeon Sulfolobus solfataricus
FUSI, PAOLA ALESSANDRA;TORTORA, PAOLO;
2004
Abstract
The unfolding induced by guanidine hydrochloride of the small protein Sso7d from the hyperthermophilic archaeon Sulfolobus solfataricus has been investigated by means of circular dichroism and fluorescence measurements. At neutral pH and room temperature the midpoint of the transition occurred at 4 M guanidine hydrochloride. Thermodynamic information was obtained by means of both the linear extrapolation model and the denaturant binding model, in the assumption of a two-state N⇔D transition. A comparison with thermodynamic data determined from the thermal unfolding of Sso7d indicated that the denaturant binding model has to be preferred. Finally, it is shown that Sso7d is the most stable against both temperature and guanidine hydrochloride among a set of globular proteins possessing a very similar 3D structure. © 2004 Elsevier B.V. All rights reservedI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.