Figure 2.

The structure of the Ro‐αG1/voglibose complex. (A) The ribbon diagram of a Ro‐αG1 dimer with voglibose bound at each active site. The two monomers of the dimer are colored in cyan and green, respectively. The two vogliboses are drawn in stick format. (B) The interaction pattern between one voglibose and its surrounding active site protein residues. The active site protein residues are drawn in stick format with carbon atoms colored in grey. The voglibose is drawn in thicker stick format with carbon atoms colored in yellow. The carbon atoms on the cyclohexane ring of voglibose are labeled in black. Hydrogen bonds are represented by magenta dashed lines. Water molecules involved in hydrogen bond network are drawn as small green spheres. The electron density map (2F _o –F _c) associated with the voglibose is represented in pink mesh at 1σ contour level. (C) The active site interaction pattern of an isomaltose in Ro‐αG1 D307A/isomaltose complex.15 The substrate‐binding mode is for comparison to inhibitor‐binding modes presented in this paper. The key residues at the active site (carbon atoms in yellow) and the substrate isomaltose (carbon atoms in cyan) are drawn in stick format. The carbon atoms on the pyranose ring of isomaltose at the −1 subsite are labeled. The three conserved water molecules involved in hydrogen bond network are drawn as small green spheres. The mutation D307A is highlighted in magenta.