Figure 10.

Involvement of water in the SH3:P41 binding interface. The five water molecules (green spheres) that were proposed to contribute to the highly favorable binding enthalpy in the Abl-SH3:P41 complex (left panel) were modeled into the R21A Spc-SH3:P41 structure (right panel) by direct superposition of the two complexes. Waters W1082 and W1105 (labeled in the Abl-SH3:P41 complex) are similarly buried in the two complexes, while the remaining three waters (highlighted by a white circle) are exposed in the R21A Spc-SH3:P41 complex and likely not anymore present in the binding interface.