Table 2.

Kinetic and affinity constants for IGF-II binding to IGF2R domain 11 proteins studied

ProteinMajor kinetic variables
Minor kinetic variables
kal (×105 mol/L−1 s−1)kdl (×10−2 s−1)KD (×10−9 mol/L)ka2 (×10−3 s−1)ka2 (×10−5 RU−1 s−1)kd2 (×10−4 s−1)
11wild-type6.62 ± 0.137.87 ± 0.29118.8 ± 3.52.45 ± 0.33121 ± 7.2
11E1544K20.23 ± 2.974.06 ± 0.2820.5 ± 2.03.83 ± 1.1079 ± 28
11I1572A
11wild-type-Fc13.65 ± 0.010.445 ± 0.043.26 ± 0.37.12 ± 0.192.33 ± 0.12
11E1544K22.27 ± 0.740.401 ± 0.031.79 ± 0.087.86 ± 0.041.26 ± 0.03
11I1572A
  • NOTE: The values given correspond to the average value ± the SE of three independent experiments. We have published the kinetic constants for non-Fc-tagged domain 11 proteins previously (44).

  • Abbreviation: RU, resonance unit.