Table 2. Thermodynamic parameters for rabbit FGF-1 in comparison with human FGF-1 determined by isothermal equilibrium denaturation using GuHCl.

Protein	ΔG (kJ mol−1)	m value (kJ mol−1  M−1)	Cm (M)	ΔΔG† (kJ mol−1)
Human FGF-1‡	21.1 ± 0.6	18.9 ± 0.6	1.11 ± 0.01	—
Rabbit FGF-1	22.2 ± 0.4	21.3 ± 0.2	1.04 ± 0.01	1.4

^†ΔΔG = (C _m,human − C _m,rabbit)(m _human + m _rabbit)/2 as described by Pace & Scholtz (1997 ▶). A negative value of ΔΔG indicates a more stable mutation; the error is stated as the standard error from triple data sets.

^‡The thermodynamic parameters of human FGF-­1 were previously characterized by Brych et al. (2003 ▶).