Stability parameters for β-lactoglobulin thermal dissociation and unfolding in phosphate buffer at pH 7.0

The thermal stability of beta-lactoglobulin (beta-Lg) dimer was reassessed based on a three-state denaturation process involving dissociation 0 and unfolding (dimer monomer 7 unfolded state). The stabilisation Gibbs free energy change for beta-Lg dissociation unfolding (DeltaG(DCU)(O)) was 57.6 kJ mol(-1) compared with an estimated 14 kJ mol(-1) with beta-Lg monomer as the reference native state. The standard enthalpy (DeltaH(O)) and entropy (Delta;S-o) change for heat denaturing beta-Lg dimer are reported. The new stability parameters are discussed in terms of protein stability function relations. (C) 2002 Elsevier Science Ltd. All rights reserved.