Pressure effect on denaturant-induced unfolding of hen egg white lysozyme

Citation
K. Sasahara et al., Pressure effect on denaturant-induced unfolding of hen egg white lysozyme, PROTEINS, 44(3), 2001, pp. 180-187
Citations number
64
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
PROTEINS-STRUCTURE FUNCTION AND GENETICS
ISSN journal
0887-3585 → ACNP
Volume
44
Issue
3
Year of publication
2001
Pages
180 - 187
Database
ISI
SICI code
0887-3585(20010815)44:3<180:PEODUO>2.0.ZU;2-I
Abstract
The influence of hydrostatic pressure (less than or equal to 100 MPa) on de naturant-induced unfolding of hen egg white lysozyme was investigated by me ans of ultraviolet spectroscopy at various temperatures. Assuming a two-sta te transition model, the dependence of Gibbs free-energy change of unfoldin g on the denaturant concentration was calculated. Under applied hydrostatic pressure, these data were interpreted as suggesting that a two-state model is not applicable in a restricted temperature range; the dominant effect o f hydrostatic pressure is to affect the cooperativity in protein unfolding due to a chemical equilibrium shift in the direction of the reduction in th e system volume. The deviation from the two-state transition model appears to be rationalized by assuming that applied pressure induces an intermediat e conformation between the native and unfolded states of the protein. The i mplication of the thermodynamic stability of protein under pressure was dis cussed. (C) 2001 Wiley-Liss, Inc.