2du0
Crystal structure of basic winged bean lectin in complex with Alpha-D-galactose
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OverviewOverview
The crystal structure of the complexes of basic winged-bean lectin with galactose, 2-methoxygalactose, N-acetylgalactosamine and methyl-alpha-N-acetylgalactosamine have been determined. Lectin-sugar interactions involve four hydrogen bonds and a stacking interaction in all of the complexes. In addition, an N-H...O hydrogen bond involving the hydroxyl group at C2 exists in the galactose and 2-methoxygalactose complexes. An additional hydrophobic interaction involving the methyl group in the latter leads to the higher affinity of the methyl derivative. In the lectin-N-acetylgalactosamine complex the N-H...O hydrogen bond is lost, but a compensatory hydrogen bond is formed involving the O atom of the acetamido group. In addition, the CH(3) moiety of the acetamido group is involved in hydrophobic interactions. Consequently, the 2-methyl and acetamido derivatives of galactose have nearly the same affinity for the lectin. The methyl group alpha-linked to the galactose takes part in additional hydrophobic interactions. Therefore, methyl-alpha-N-acetylgalactosamine has a higher affinity than N-acetylgalactosamine for the lectin. The structures of basic winged-bean lectin-sugar complexes provide a framework for examining the relative affinity of galactose and galactosamine for the lectins that bind to them. The complexes also lead to a structural explanation for the blood-group specificity of basic winged-bean lectin.
About this StructureAbout this Structure
2DU0 is a Single protein structure of sequence from Psophocarpus tetragonolobus with , , and as ligands. Full crystallographic information is available from OCA.
ReferenceReference
Structural basis for the carbohydrate-specificity of basic winged-bean lectin and its differential affinity for Gal and GalNAc., Kulkarni KA, Katiyar S, Surolia A, Vijayan M, Suguna K, Acta Crystallogr D Biol Crystallogr. 2006 Nov;62(Pt 11):1319-24. Epub 2006, Oct 18. PMID:17057334
Page seeded by OCA on Thu Feb 21 17:02:36 2008