Fig. 3
Structural analysis of PKM2 wild-type and variants. a The 2Fo-Fc electron density map of H391Y and R399E. The map is contoured at the 1.1-σ level. b Superposition between wild-type (R-state, green), H391Y (cyan), and R399E (gray) monomers. Mutated residues are shown as heavy sticks. FBP, serine, and oxalate are drawn as ball-and-stick models. The carbon, oxygen, and nitrogen atoms are colored yellow, red, and blue, respectively. c Structural analysis of wild-type PKM2 and H391Y shows that H391Y possesses a strong hydrogen bond contact between Y391 and E386. The right panel is a zoomed region of 30 degree rotation clockwise of the left panel. d Comparison between wild-type PKM2 and R399E shows that R399E fails to form a salt-bridge network among R399, E396, and E418 at the C−C interface. The right panel is a zoomed region of the left panel. Residues (E386, H391, Y391, R399, E399, E396, and E418) are shown as sticks. The oxygen and nitrogen atoms are colored red and blue, respectively. wild-type (PDB: 3SRD; green); H391Y (PDB: 4YJ5, this study; cyan); and R399E (PDB: 5X0I, this study; gray)
