Table 1.

Kinetic parameters for the hydrogen bond network mutants

Mutant	ln(kf)0M	ln(ku)3M	mf	mu	ΔGU–F	ΔΔGU–F
WT*	4.10	0.139	1.02	0.54	3.95	—
E30A*	2.03	1.48	1.09	0.65	2.28	−2.00
S47A*	2.01	0.537	1.50	0.44	2.18	−1.46
T50A*	1.99	0.750	1.84	0.47	2.14	−1.60
E30A_S47A	1.21	1.39	†	0.46	1.28	−2.43
E30A_T50A	1.32	1.66	†	0.39	0.977	−2.52
WT_pH3	2.08	1.69	1.08	0.41	1.46	−2.09
S47A_pH3	0.052	1.59	1.45	0.38	0.249	−3.23

Kinetics of folding and unfolding were followed by changes in tryptophan fluorescence on a stopped flow instrument at 295 K; k_f is reported in the absence of denaturant, and k_u is in 3 M Gnd to avoid extrapolation; m_f and m_u are the dependences of the folding and the unfolding rates, respectively, on Gnd. ΔG_U–F (free energy of unfolding) and ΔΔG_U–F (the difference in ΔG_U–F between WT and the mutant proteins) were calculated from the kinetic parameters as described in the Methods section. Typical errors for the kinetic measurements are 1–10% as reported in ref. 13. 

^*Kinetic data for these mutants were published previously in ref. 12. 

^† These values could not be estimated reliably because of the small region over which k_f can be measured.