A stereo diagram of MB bound in a pocket of the third module (a) and its right side (b), where three Asn residues are closely localized. MB adopts a bracket-shaped conformation stabilized by two C—H⋯O hydrogen bonds. The two hydroxyl groups in the equatorial configuration of the second mannose residue are recognized, each by two hydrogen bonds (the average distances are shown in Å). The O1 atom is drawn as a grey sphere. Dashed and dotted lines indicate possible hydrogen bonds with their average distances and van der Waals spheres, respectively.