Figure 3.

Panel A: Linear Free Energy Relationship (LFER) plots obtained from the analysis of kinetic data for the binding of N-SH2 domain with Gab2_608–620. Broken line represents the best fit to a linear equation for all the points on the plot. Continuous line represents the best fit to a linear equation by excluding T42S, T52S, I56V, L65A and L88A points (details in the text). Panel B: Comparison of the LFER plots obtained for the N-SH2 domain of PI3K (gray line) and the N-SH2 domain of SHP2 (black line). It is evident that the two linear functions display identical slopes. Panel C: Plot displaying the activation free energy (ΔΔG_# (black dots)) and equilibrium free energy (ΔΔG_eq (gray dots)) values for all the site-directed variants of N-SH2 from Table 1 as a function of their thermodynamic stability (data taken from [27]).