Urea-induced unfolding of Glossoscolex paulistus hemoglobin, in oxy- and cyanomet-forms: A dissociation model

► HbGp unfolding process, in presence of urea, is characterized by two phases. ► At low urea concentrations, up to 4.0 mol/L oligomeric dissociation is observed. ► An intermediate state is assigned to oligomeric dissociation equilibrium. ► At high urea concentrations the dissociated subunits undergo unfolding. ► Oxy- and cyanomet-HbGp have similar unfolding patterns.