title: X-ray crystal structure of the human galectin-3 carbohydrate recognition domain at 2.1-A resolution.
abstract: Galectins are a family of lectins which share similar carbohydrate recognition domains (CRDs) and affinity for small beta-galactosides, but which show significant differences in binding specificity for more complex glycoconjugates. We report here the x-ray crystal structure of the human galectin-3 CRD, in complex with lactose and N-acetyllactosamine, at 2.1-A resolution. This structure represents the first example of a CRD determined from a galectin which does not show the canonical 2-fold symmetric dimer organization. Comparison with the published structures of galectins-1 and -2 provides an explanation for the differences in carbohydrate-binding specificity shown by galectin-3, and for the fact that it fails to form dimers by analogous CRD-CRD interactions.
authors.affiliation: Departments of Molecular and Medical Genetics and Biochemistry, University of Toronto, Toronto, Ontario, M5S 1A8, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Seetharaman
authors.forename: A
authors.initials: A
authors.lastname: Kanigsberg
authors.forename: R
authors.initials: R
authors.lastname: Slaaby
authors.forename: H
authors.initials: H
authors.lastname: Leffler
authors.forename: S H
authors.initials: SH
authors.lastname: Barondes
authors.forename: J M
authors.initials: JM
authors.lastname: Rini
mesh_terms: D000818:Animals; D000943:Antigens, Differentiation / Q000737:chemistry / Q000378:metabolism*; D001665:Binding Sites; D050260:Carbohydrate Metabolism; D018360:Crystallography, X-Ray; D019281:Dimerization; D037483:Galectin 1; D037501:Galectin 2; D037502:Galectin 3; D006388:Hemagglutinins / Q000737:chemistry; D006801:Humans; D008958:Models, Molecular
chemical_list: D000943:Antigens, Differentiation; D037483:Galectin 1; D037501:Galectin 2; D037502:Galectin 3; D006388:Hemagglutinins