Legume lectin of view of protein structure. Despite the conserved structure of the legume lectin subunit, they can adopt a wide range of quaternary structures. The reason behind this remarkable variability is probably to be found in the interaction with multivalent ligands. Legume lectin The legume lectins (or L-type lectins) are a family of sugar-binding proteins or lectins found in the seeds and, in smaller amounts, in the roots, stems, leaves and bark of plants belonging to the Fabaceae family. The exact function of the legume lectins "in vivo" is unknown but they are probably involved in the defense of plants against
Lectin their particular high specificity for foreign glycoconjugates (e.g. those of fungi, invertebrates, and animals) and used in biomedicine for blood cell testing and in biochemistry for fractionation. Although they were first discovered more than 100 years ago in plants, now lectins are known to be present throughout nature. It is generally believed that the earliest description of a lectin was given by Peter Hermann Stillmark in his doctoral thesis presented in 1888 to the University of Dorpat. Stillmark isolated ricin, an extremely toxic hemagglutinin, from seeds of the castor plant ("Ricinus communis"). The first lectin to be purified on a