Lectin that binds galactose. Homotetramer. Seed. Partially N-glycosylated at Asn-111 and Asn-183 with the heptasaccharide [(beta-xylosyl-1,2)(alpha-mannosyl-1,6)(alpha-mannosyl-1,3)]beta-manosyl-1,4-GlcNAC-beta-1,4-GlcNAc-beta-1,4 [alpha-fucosyl-1,3]GlcNAc. A small proportion of alpha chains are proteolytically cleaved at 114-115 into gamma and beta chains. This is probably dependent on the deglycosylation of Asn-111. Binds one manganese (or another transition metal) ion and one calcium ion. The metal ions are essential for the saccharide-binding and cell-agglutinating activities (By similarity). Belongs to the leguminous lectin family.