Table 1 Summary of kinetic and thermodynamic data of HaloTag and its mutants (error bars are SDs of at least three separate measurements).
Data from equilibrium experiments
ΔGunf (kcal⋅mol−1) (CD)6.03 ± 0.39
m value (kcal⋅mol−1 M−1)1.57 ± 0.11
Data from kinetic experiments
ΔGunf (kcal⋅mol−1)5.24 ± 2.0
m value (kcal⋅mol−1 M−1)1.41 ± 0.58
kf,H2O (s−1)0.04 ± 0.02
mf (kcal⋅mol−1 M−1)1.46 ± 0.71
kconstant, H2O (s−1)6.6 ± 0.71 × 10−4
mconstant (kcal⋅mol−1 M−1)0.02 ± 0.1
kf, H2O,FP (s−1)4.8 ± 0.6 × 10−4
mFP (kcal⋅mol−1 M−1)−0.1 ± 0.04
kNI, H2O (s−1)8.47 ± 20 ± 10−6
mNI (kcal⋅mol−1 M−1)−0.44 ± 0.3
kIU, H2O (s−1)3.3 ± 9.9 × 10−4
mIU (kcal⋅mol−1 M−1)0.70 ± 0.15
Data from cysteine accessibility experiments
kWT,refolding, slow (s−1)7.8 ± 0.6 ± 10−4
kWT,refolding, fast (s−1)0.03 ± 0.02
kWT,IVT (s−1)4.7 ± 0.3 × 10−4
kM129C,refolding (s−1)>0.01
kM129C,IVT (s−1)3.2 ± 0.2 × 10−4
kI126C,refolding (s−1)>0.01
kI126C,IVT (s−1)2.2 ± 0.2 × 10−4
kE121C,refolding (s−1)>0.01
kE121C,IVT (s−1)>0.01