D-mannose/D-glucose-binding lectin (PubMed:9779592). Binds N-linked high-mannose-type glycans. Has a preference for smaller (Man(2)-Man(6)) high-mannose-type glycans to larger (Man(7)-Man(9)) ones. Recognizes both alpha1-6 extended and alpha1-3 extended monoantennary glycans. The addition of alpha1-2Man to the Man-alpha1-3Man-beta branch results in a significant loss of affinity, but beta1-2GlcNAc has some affinity. Has less affinity for biantennary glycans, and affinity is very weak for the biantennary complex-type N-glycans with bisecting GlcNAc. No affinity is observed for tri- and tetra-antennary glycans (PubMed:18266762). Has mitogenic and hemagglutinating activities (PubMed:9779592). Belongs to the jacalin lectin family.