The crystal structures of the HBGA-binding interfaces of VA387 (GII.4) and VA207 (GII.9).

(A and B) The surface models of the P dimers (top views) of VA387 (A) and VA207 (B). One protomer is shown in light cyan, while the other in grey. The HBGA-binding interfaces are shown in darker colors. (C and D) Enlargements of the HBGA-binding interfaces with labels of individual amino acids. The prime symbol indicates a residue of the other protomer. The three major components of the binding pocket are colored in blue (bottom), orange (wall), and yellow/sand (another wall), respectively, while the nearby site that affects specificity of the binding interface is shown in purple. The type B trisaccharide binding to VA387 (A and C) is shown in cyan (C), red (O), and blue (N), while the Le^y tetrasaccharide binding to VA207 (B and D) is shown in green (C), red (O), and blue (N).