Table 2.

Equilibrium Unfolding Transition Midpoints of Alpha-1 Antitrypsin Variants

Variant	Midpoint* (GdnHCl M)
	N→I	I→U
ATM	0.94 ± 0.03	2.43 ± 0.03
ATZ	1.33 ± 0.09	2.43 ± 0.06
ATAla336Pro	0.42 ± 0.04	2.27 ± 0.03

Definition of abbreviations: AT_A336Pro, alpha-1 antitrypsin Ala336Pro (Baghdad variant); AT_M, wild-type alpha-1 antitrypsin (M variant); AT_Z, alpha-1 antitrypsin Glu342Lys (Z variant); GdnHCl, guanidium hydrochloride; I, intermediate; M, units of concentration in molar; N, native; U, unfolded states of alpha-1 antitrypsin.

^*The midpoints of denaturation (in guanidium hydrochloride) were obtained by fitting a function describing three-state unfolding to the equilibrium denaturation profiles in Figure 3A. The standard errors of the fits are shown.