Abstract

The physiological stability curve -- a plot of the free energy of unfolding versus temperature -- is calculated for hen egg white lysozyme from a combination of extrapolated unfolding thermodynamic data from reversible conditions and isothermal titrations with guanidine hydrochloride. The shape of the curve suggests the existence of only one folded conformation.

Keywords: differential scanning calorimetry (DSC), protein stability, Titration, Gibbs-Helmholtz equation, lysozyme stability, guanidine hydrochloride