D-galactose specific lectin. Binds in decreasing order of affinity: melibiose, methyl-alpha-D-galactoside, D-galactose, methyl-beta-D-galactoside, N-acetyl-D-galactosamine. Similar to plant lectins in its selective (carbohydrate-specific) hemagglutinating activity. Low exposure on the cell surface. Belongs to the LecA/PllA lectin family.