FIGURE 9.

GdmCl-induced unfolding transitions of Tslig monitored by size-exclusion chromatography. Dependence of elution volumes V^el of deadenylated (A) and adenylated (B) Tslig on GdmCl concentrations. 〈V_C〉, elution volumes of “compact” molecules and elution volumes of “compact” molecules and 〈V_LC〉, elution volumes of “less compact” molecules elution volumes of “less compact” molecules. LC_max, maximal value of V^el for less compact molecules. N, native state; MG_SW, swollen molten globule state; PMG, premolten globule state; U, unfolded state. Stages of unfolding (four-state transition) of deadenylated (C) and adenylated (D) Tslig. (C) Fraction of denatured molecules f_D was obtained from the relative change of elution volumes from 0 to 3.53 M GdmCl (N↔MG transition) (▪); f_LC, fraction of less compact molecules (▴); f_U, fraction of unfolded molecules (•); fluorescence average emission wavelength, (dash-dotted line). (D) Fraction of denatured molecules f_D obtained from the relative change of near UV ellipticity [θ]₂₈₀ (□) and the relative change of elution volumes from 0 to 4.34 M GdmCl (N↔MG transition) (▪); f_LC, (▴); f_U, (•); relative change of far UV ellipticity [θ]₂₂₂ (dashed line). Multiple-state GdmCl-induced N↔U transition in deadenylated (E) and adenylated (F) Tslig presented in terms of fractions of different states: f_N, fraction of molecules in the native state; f_MG, fraction in the molten-globule state; f_PMG, fraction in the premolten globule state, and f_U, fraction in the unfolded state.