2DU1

Crystal Structure of basic winged bean lectin in complex with Methyl-alpha-N-acetyl-D galactosamine

Summary for 2DU1

• Entry DOI: 10.2210/pdb2du1/pdb
• Related: 1wbf 1wbl 2DTW 2DU0 2DUY 2d3s
• Descriptor: Basic agglutinin, alpha-L-fucopyranose-(1-3)-[2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)]2-acetamido-2-deoxy-beta-D-glucopyranose, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (8 entities in total)
• Functional Keywords: legume lectin, glycosylated protein, agglutinin, sugar binding protein
• Biological source: Psophocarpus tetragonolobus (winged bean)
• Total number of polymer chains: 4
• Total formula weight: 110713.61

Authors

Kulkarni, K.A.,Katiyar, S.,Surolia, A.,Vijayan, M.,Suguna, K. (deposition date: 2006-07-19, release date: 2006-11-07, Last modification date: 2023-10-25)

Primary citation

Kulkarni, K.A.,Katiyar, S.,Surolia, A.,Vijayan, M.,Suguna, K.
Structural basis for the carbohydrate-specificity of basic winged-bean lectin and its differential affinity for Gal and GalNAc
ACTA CRYSTALLOGR.,SECT.D, 62:1319-1324, 2006

PubMed Abstract: 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.

PubMed: 17057334
DOI: 10.1107/S0907444906028198

Experimental method

X-RAY DIFFRACTION (2.6 Å)