1DBN

MAACKIA AMURENSIS LEUKOAGGLUTININ (LECTIN) WITH SIALYLLACTOSE

1DBN の概要

• エントリーDOI: 10.2210/pdb1dbn/pdb
• 分子名称: PROTEIN (LEUKOAGGLUTININ), N-acetyl-alpha-neuraminic acid-(2-3)-beta-D-galactopyranose-(1-4)-beta-D-glucopyranose, 2-acetamido-2-deoxy-beta-D-glucopyranose, ... (6 entities in total)
• 機能のキーワード: plant lectin, carbohydrate binding, sialyllactose, sugar binding protein
• 由来する生物種: Maackia amurensis
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 54538.41

構造登録者

Imberty, A.,Gautier, C.,Lescar, J.,Loris, R. (登録日: 1999-11-03, 公開日: 2000-06-14, 最終更新日: 2024-10-09)

主引用文献

Imberty, A.,Gautier, C.,Lescar, J.,Perez, S.,Wyns, L.,Loris, R.
An unusual carbohydrate binding site revealed by the structures of two Maackia amurensis lectins complexed with sialic acid-containing oligosaccharides.
J.Biol.Chem., 275:17541-17548, 2000

PubMed Abstract: Seeds from the legume tree Maackia amurensis contain two lectins that can agglutinate different blood cell types. Their specificity toward sialylated oligosaccharides is unique among legume lectins; the leukoagglutinin preferentially binds to sialyllactosamine (alphaNeuAc(2-3)betaGal(1-4)betaGlcNAc), whereas the hemagglutinin displays higher affinity for a disialylated tetrasaccharide (alphaNeuAc(2-3)betaGal(1-3)[alphaNeuAc(2-6)]alphaG alNAc). The three-dimensional structure of the complex between M. amurensis leukoagglutinin and sialyllactose has been determined at 2.75-A resolution using x-ray crystallography. The carbohydrate binding site consists of a deep cleft that accommodates the three carbohydrate residues of the sialyllactose. The central galactose sits in the primary binding site in an orientation that has not been observed previously in other legume lectins. The carboxyl group of sialic acid establishes a salt bridge with a lysine side chain. The glucose residue is very efficiently docked between two tyrosine aromatic rings. The complex between M. amurensis hemagglutinin and a disialylated tetrasaccharide could be modeled from the leukoagglutinin/sialyllactose crystal structure. The substitution of one tyrosine by an alanine residue is responsible for the difference in fine specificity between the two isolectins. Comparison with other legume lectins indicates that oligosaccharide specificity within this family is achieved by the recycling of structural loops in different combinations.

PubMed: 10747930
DOI: 10.1074/jbc.M000560200

実験手法

X-RAY DIFFRACTION (2.75 Å)