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Table 4 Results from binding and activity studies on mutated TtSlyD variants

From: Molecular insights into substrate recognition and catalytic mechanism of the chaperone and FKBP peptidyl-prolyl isomerase SlyD

Construct Mutation N1 KD1 (μM) ΔH1 (kcal/mol) –T · ΔS1 (kcal/mol) N2 KD2 (μM) ΔH2 (kcal/mol) –T · ΔS2 (kcal/mol) Activity (kcat/KM 106 M/s) Relative activity (%)
TtSlyDFL Wild type 0.96 ± 0.03 0.113 ± 0.012 –10.0 ± 0.11 0.7 0.96 ± 0.02 2.93 ± 0.12 –4.9 ± 0.22 –2.5 1.47 ± 0.05 100
Y13F 0.85 ± 0.03 0.107 ± 0.011 –10.6 ± 0.14 0.5 0.87 ± 0.02 3.94 ± 0.14 –5.9 ± 0.47 –2.6 1.35 ± 0.17 92
D23A 0.92 ± 0.03 0.075 ± 0.042 –2.0 ± 0.11 1.3 0.88 ± 0.01 1.65 ± 0.15 –6.0 ± 0.11 –2.1 1.15 ± 0.21 78
N35A 0.98 ± 0.02 0.169 ± 0.032 –9.7 ± 0.11 0.6 1.06 ± 0.05 5.18 ± 0.89 –2.5 ± 0.33 –4.6 1.04 ± 0.28 71
I37G 0.93 ± 0.05 0.134 ± 0.038 –9.0 ± 0.11 –0.3 0.91 ± 0.03 3.64 ± 0.33 –6.6 ± 0.37 –0.7 0.73 ± 0.12 50
Y63F 0.81 ± 0.01 0.030 ± 0.003 –11.3 ± 0.11 1.1 0.78 ± 0.02 1.58 ± 0.22 –6.0 ± 0.29 –2.2 1.12 ± 0.11 76
Y63A 0.80 ± 0.01 0.041 ± 0.007 –9.4 ± 0.06 –0.5 0.84 ± 0.02 3.18 ± 0.29 –4.7 ± 0.15 –2.7 0.31 ± 0.19 21
A78G 1.08 ± 0.02 0.262 ± 0.023 –8.2 ± 0.06 –0.6 1.09 ± 0.02 5.24 ± 0.43 –2.8 ± 0.19 –4.3 0.76 ± 0.14 52
Y92A 0.96 ± 0.02 0.254 ± 0.022 –8.7 ± 0.51 –0.1 0.92 ± 0.01 4.33 ± 0.14 –5.3 ± 0.15 –1.9 0.53 ± 0.12 36
Q94A 1.03 ± 0.03 0.288 ± 0.042 –8.6 ± 0.10 –0.2 0.93 ± 0.02 5.98 ± 0.44 –4.3 ± 0.38 –2.8 1.44 ± 0.49 98
M96A 1.00 ± 0.01 0.129 ± 0.009 –9.7 ± 0.04 0.4 1.01 ± 0.01 3.86 ± 0.21 –4.4 ± 0.13 –2.9 0.58 ± 0.15 39
H119A 0.87 ± 0.03 0.060 ± 0.012 –11.1 ± 0.05 0.7 0.82 ± 0.02 2.22 ± 0.28 –6.2 ± 0.47 –2.2 1.23 ± 0.02 84
F128A 0.88 ± 0.02 0.215 ± 0.022 –9.7 ± 0.36 1.2 0.89 ± 0.02 1.62 ± 0.11 –8.0 ± 0.52 –1.2 0.52 ± 0.16 35
TtSlyDΔIF Wild type      0.88 ± 0.02 12.23 ± 0.24 –5.9 ± 0.11 0.4 0.85 ± 0.01 58
  1. The affinities and thermodynamic parameters were determined at 20 °C for the wild type S2 peptide using isothermal titration calorimetry, while the activities were determined for the suc-ALPF-pNA tetrapeptide using nuclear magnetic resonance spectroscopy. TtSlyD ΔIF TtSlyD constructs with the insert-in-flap domain replaced by the flap loop from human FKBP12, TtSlyD FL full-length TtSlyD