The use of thermodynamic models has been of great importance for the study of folding-unfolding process of proteins, including the effect of ligands and protein-protein interaction on the stability of the native folded state (N). In the present work we propose the formalism based on thermodynamics equilibrium which describes an oligomeric protein (Nn) of n subunits that is in equilibrium with the dissociated native monomer N and its unfolded state D throughout the respective sequential intermediate n-i states (oligomeric conformers where i=0,2, 4,…n), according to the scheme (a). Defining the relative partition function for the protein system we attained the analytical expression of the enthalpy relative to the reference state. The heat capacity can be obtained by derivative of the enthalpy with respect to the temperature. We study the evolution of the system given in (a) by simulating different experimental conditions and thermodynamic parameters. The developed model offers a solid tool to characterize complex calorimetric thermogram profiles with the contribution and identification of each species in the system.
