Fig. 4. Water molecules indispensable for the reaction pathway.

Chains A and B are shown in cyan and light green, respectively. Hydrogen bonds with distances (Å, red numbers) are shown as yellow dotted lines. Substrates are shown as white sticks. a Residues sequestering water molecules on the reaction pathway. All residues used for fixing Wat1–3 on the reaction pathway are shown as sticks. Blue dotted lines represent a route from the nucleophile to a substrate hydroxy group on the reaction pathway. b, c The environment around the sequestered Wat1 (b) and Wat2 and Wat3 (c). b The substrate and T386 and W441 are shown as spheres with van der Waals radii. c The substrate is shown in stick representation. C1, C5, O5, and O6 atoms of the Glc moiety at subsite –3 are shown as semi-translucent spheres with van der Waals radii.