Figure 2.

The effects of mutations on site 1 binding affinity for the hGHR mapped onto the structure of hGH_wt (A–C) or hGH_v (D–F). The maps show the effects of substitution by homologous residues (A,D), serine (B,E), or alanine (C,F). The residues are colored according to the ΔΔG_mut-wt values shown in Table 2 and Figure 1 ▶, as follows: cyan< −0.4 kcal/mol; −0.4 kcal/mol ≤ green<0.4 kcal/mol; 0.4 kcal/ mol ≤ orange<1.0 kcal/mol; red ≥ 1.0 kcal/mol; gray, untested. The structures were derived from the 2:1 hGHR-ECD:hGH complexes for hGH_wt (de Vos et al. 1992) and hGH_v (Schiffer et al. 2002), and were rendered as molecular surfaces using Pymol (DeLano Scientific).