title: Are vicilins another major class of legume lectins?
abstract: Legume lectins comprise a structurally related, Ca/Mn-dependent, widespread, abundant and well characterized lectin family when compared to the large number of lectins from other sources described in the literature. Strangely enough, no specific function has been assigned to them aside from a possible role in storage and/or defense. Using a recent and fine-tuned methodology capable of specific lectin identification, β-conglutin, Vicia faba vicilin and β-lathyrin, the vicilin storage globulins from Lupinus albus, V. faba and Lathyrus sativus, respectively, were shown to be capable of affinity binding to thoroughly washed erythrocyte membranes and of specific elution with appropriate sugars. Based on this evidence and on sparse data published in the literature, a second family of legume lectins is proposed: the 7S family of storage proteins from leguminous seeds, or family II of legume lectins. These lectins are also structurally related, widespread and well characterized. In addition, they self-aggregate in a Ca/Mg, electrostatic dependent manner and are even more abundant than the family I of legume lectins. Using the same evidence, reserve and defense roles may be attributed to family II of legume lectins.
authors.affiliation: Faculdade de Farmácia de Lisboa, Lisbon University, Lisboa 1649-003, Portugal. acribeiro@ff.ul.pt.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Ribeiro
authors.affiliation: CEV, S.A, Zona Industrial de Cantanhede/Biocant Park, Cantanhede 3060-197, Portugal. sam@cev.com.pt.
authors.forename: Sara V
authors.initials: SV
authors.lastname: Monteiro
authors.affiliation: Faculdade de Medicina Veterinária, Lisbon University, Lisboa 1300-477, Portugal. belmira@fmv.utl.pt.
authors.forename: Belmira M
authors.initials: BM
authors.lastname: Carrapiço
authors.affiliation: Centro de Botânica Aplicada à Agricultura, Instituto Superior de Agronomia, Lisbon University, Lisboa 1349-017, Portugal. rbferreira@isa.ulisboa.pt.
authors.forename: Ricardo B
authors.initials: RB
authors.lastname: Ferreira
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002241:Carbohydrates / Q000494:pharmacology; D005591:Chemical Fractionation; D004910:Erythrocyte Membrane / Q000378:metabolism; D007887:Fabaceae / Q000737:chemistry*; D006384:Hemagglutination / Q000187:drug effects; D006386:Hemagglutination Tests; D008969:Molecular Sequence Data; D037121:Plant Lectins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D011485:Protein Binding; D021122:Protein Subunits; D011817:Rabbits; D055314:Seed Storage Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D012639:Seeds / Q000737:chemistry
chemical_list: D002241:Carbohydrates; D037121:Plant Lectins; D010940:Plant Proteins; D021122:Protein Subunits; D055314:Seed Storage Proteins; C015575:vicilin protein, plant