Fig. 5.

A multitude of potential cryptic allosteric sites in (A) β-lactamase, (B) IL-2, and (C) RNase H. The 50 most frequently open pockets are shown as yellow spheres, each representing a pocket with a radius of up to 5 Å (SI Text). Sidechains within each coupled community are rendered in the same color. They are depicted as spheres if they are in the active site and as sticks otherwise. There are five communities for β-lactamase, six for IL-2, and four for RNase H. Almost every community contains at least one active site residue in each protein, so the vast majority of transient pockets could serve as cryptic sites. The light-blue, dashed circles encompass the known allosteric sites in β-lactamase and IL-2 and the backbone of each protein is colored from blue to red starting at the N terminus.