The indicated parameters were calculated from a mathematical model, based on standard equilibrium binding equations, as described in the Supplementary Materials.
Binding constant at pTyr171 (Kd3) (nM) | First sequential constant for binding of a single Gads at either site (Kd1 = 0.5 × Kd3) (nM) | Second sequential binding constant (Kd2) (nM) | Fold increase in site-specific binding affinity at second binding event due to cooperativity (Kd3/Kd2) | |
WT SH2 | 177 | 88.5 | 0.95 | 186.5 |
F92D SH2 | 472 | 236 | 5.4 | 86.7 |
Source | Set equal to pTyr171 dissociation constant from Fig. 2E | On the basis of an assumption of equivalence of the two binding sites | Calculated from mathematical model of competitive binding data from Fig. 4C |