Fig. 5

Superposition of structures of crizotinib in complexes with ALK (PDB: 2XP2; orange/brick) and MET (PDB: 2WGJ, violet/indigo). Side chains within a contact distance of 4 Å are shown as sticks, while main chain hydrogen bonding contact atoms are shown as small spheres. A dashed line indicates the approximate position of the disordered glycine-rich loop of Alk. The side chains of the activation loop phosphorylation sites are widely separated, with Tyr-1230 of MET in a pi–pi interaction with crizotinib, and Tyr-1278 of ALK anchored away from the ATP pocket by a helical conformation of the activation loop. The structure of crizotinib in complex with ALK mutant L1196M is similar to 2XP2, excepting the gatekeeper mutation