Table 1.

Comparison of thermodynamic parameters for ParB before and after modification^§

Protein	[GdmCl]1/2	m	ΔGU,H2O
	(M)	(kJ/mol/M)	(kJ/mol)
Nuclease	3.01 ± 0.01	19 ± 1	57.4 ± 3.0
Nuclease (modified)	2.74 ± 0.01	14.4 ± 0.5	39.4 ± 1.4

^§ The values for GdmCl denaturation were obtained by fitting data to a standard 2-state model [29] where [GdmCl]_1/2 is the midpoint and m the slope of the denaturation transition. ΔG_U,H2O is the free energy of unfolding at 25°C in the absence of denaturant. The errors shown are the standard errors from the fit. The dependence of ΔG_U on the GdmCl concentration is given by ΔG_(GdmCl) = Δ G_u-m [GdmCl]. Conditions were as described in the legend for Figure 5A. The thermal denaturation data (Figure 5B) was also fitted to a 2-state model and was extrapolation to standard conditions (25°C in the absence of denaturant) as described previously [30]. The value of ΔG_U,H2O thus obtained is the same within the error as that shown above.