title: Crystal structure of Pterocarpus angolensis lectin in complex with glucose, sucrose, and turanose.
abstract: The crystal structure of the Man/Glc-specific seed lectin from Pterocarpus angolensis was determined in complex with methyl-alpha-d-glucose, sucrose, and turanose. The carbohydrate binding site contains a classic Man/Glc type specificity loop. Its metal binding loop on the other hand is of the long type, different from what is observed in other Man/Glc-specific legume lectins. Glucose binding in the primary binding site is reminiscent of the glucose complexes of concanavalin A and lentil lectin. Sucrose is found to be bound in a conformation similar as seen in the binding site of lentil lectin. A direct hydrogen bond between Ser-137(OG) to Fru(O2) in Pterocarpus angolensis lectin replaces a water-mediated interaction in the equivalent complex of lentil lectin. In the turanose complex, the binding site of the first molecule in the asymmetric unit contains the alphaGlc1-3betaFruf form of furanose while the second molecule contains the alphaGlc1-3betaFrup form in its binding site.
authors.affiliation: Laboratorium voor Ultrastructuur, Instituut voor Moleculaire Biologie, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium. reloris@vub.ac.be
authors.forename: Remy
authors.initials: R
authors.lastname: Loris
authors.forename: Anne
authors.initials: A
authors.lastname: Imberty
authors.forename: Sonia
authors.initials: S
authors.lastname: Beeckmans
authors.forename: Edilbert
authors.initials: E
authors.lastname: Van Driessche
authors.forename: John S
authors.initials: JS
authors.lastname: Read
authors.forename: Julie
authors.initials: J
authors.lastname: Bouckaert
authors.forename: Henri
authors.initials: H
authors.lastname: De Greve
authors.forename: Lieven
authors.initials: L
authors.lastname: Buts
authors.forename: Lode
authors.initials: L
authors.lastname: Wyns
mesh_terms: D001665:Binding Sites; D003460:Crystallization; D004187:Disaccharides / Q000737:chemistry* / Q000378:metabolism; D005947:Glucose / Q000737:chemistry* / Q000378:metabolism; D008968:Molecular Conformation; D037121:Plant Lectins / Q000737:chemistry* / Q000378:metabolism; D035721:Pterocarpus / Q000737:chemistry*; D013395:Sucrose / Q000737:chemistry* / Q000378:metabolism
chemical_list: D004187:Disaccharides; D037121:Plant Lectins; D013395:Sucrose; C029454:turanose; D005947:Glucose