Table 4.

Parameters characterizing the thermal unfolding of RNase Sa and hydrophobic variants in 30 mM MOPS, pH 7.0 ^a

Variant	ΔHmb (kcal mol−1)	Δ Smc (cal mol−1 K−1)	ΔTmd (°C)	Δ(ΔG) e (kcal mol −1)
WT	92	286	-	-
L8A	89	283	− 5.0	− 1.34
L11A	78	252	− 11.9	− 3.08
L19A	73	236	− 13.8	− 3.65
L21A	85	265	− 1.6	− 0.41
I22V	74	234	− 5.7	− 1.48
I58V	89	277	0.11	0.00
I70V	87	274	− 3.4	− .94
I71V	80	249	− 0.3	− 0.13
L91A	91	288	− 3.2	− 0.84
I92V	84	266	− 3.9	− 1.00

^aThe thermal denaturation curves were analyzed as described. ⁹⁸ The data in the table is the average value of three experiments.

^bEnthalpy of unfolding at T_m. The error is ± 5 kcal mol⁻¹.

^cΔ H_m/T_m. The error is ± 15 cal mol⁻¹ K⁻¹.

^dΔ T_m = T_m (variant) − T_m (WT). The T_m for WT is 48.4 °C.⁴⁰

^eΔ(ΔG) = ΔT_m × the average Δ S_m value of WT and the variants (264 cal mol⁻¹ K⁻¹).