Structural basis of carbohydrate recognition by a Man(alpha1-2)Man-specific lectin from Bowringia milbraedii.

TitleStructural basis of carbohydrate recognition by a Man(alpha1-2)Man-specific lectin from Bowringia milbraedii.
Publication TypeJournal Article
Year of Publication2006
AuthorsButs, L., A. Garcia-Pino, L. Wyns, and R. Loris
JournalGlycobiology
Volume16
Issue7
Pagination635-40
Date Published2006 Jul
Type of Articlelectins
ISSN0959-6658
KeywordsBinding Sites, Carbohydrates, Crystallography, X-Ray, Dimerization, Disaccharides, Fabaceae, Mannose-Binding Lectins, Mannosides, Plant Lectins, Protein Structure, Quaternary, Seeds, Solutions
Abstract

The crystal structure of the seed lectin from the tropical legume Bowringia milbraedii was determined in complex with the disaccharide ligand Man(alpha1-2)Man. In solution, the protein exhibits a dynamic dimer-tetramer equilibrium, consistent with the concanavalin A-type tetramer observed in the crystal. Contacts between the tetramers are mediated almost exclusively through the carbohydrate ligand, resulting in a crystal lattice virtually identical to that of the concanavalin-A:Man(alpha1-2)Man complex, even though both proteins have less than 50% sequence identity. The disaccharide binds exclusively in a "downstream" binding mode, with the non-reducing mannose occupying the monosaccharide-binding site. The reducing mannose is bound in a predominantly polar subsite involving Tyr131, Gln218, and Tyr219.

DOI10.1093/glycob/cwj109
Alternate JournalGlycobiology
PubMed ID16567368