FIGURE 2.
Slab view showing the central pore of LacY with the docked positions of lactose close to position 322. (A) Lactose H-bonds to H322 and B) N322 not at Q, F or K 322. (C) Stachyose also H-bonds between a glycosidic oxygen and H322. (D–F) Positions of lactose docked to glutamine, phenylalanine, and lysine mutations of H322. None of these has any lactose H-bonded at position 322.