Lectin that specifically binds alpha-galactoside-terminating glycoconjugates. Shows high apparent binding to the alpha-Gal epitope (Gal-alpha-1,3-Gal-beta-1,4-GlcNAc terminating glycans) as well as to Gal-alpha-1,4-GlcNAc and Gal-alpha-1,3-GalNAc. Gal-alpha-1,3-GalNAc may be one natural ligand bound by PllA both in the nematode symbiont and in infected insects. Homotetramer. Can be used as a fluorescent probe for the specific detection and visualization of the alpha-Gal epitope present on porcine tissues. This epitope is mainly responsible for hyperacute rejection of porcine organ transplants in humans during xenotransplantation. Belongs to the LecA/PllA lectin family.