1dbn
From Proteopedia
(New page: 200px<br /><applet load="1dbn" size="450" color="white" frame="true" align="right" spinBox="true" caption="1dbn, resolution 2.75Å" /> '''MAACKIA AMURENSIS LE...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1dbn.gif|left|200px]]<br /><applet load="1dbn" size=" | + | [[Image:1dbn.gif|left|200px]]<br /><applet load="1dbn" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1dbn, resolution 2.75Å" /> | caption="1dbn, resolution 2.75Å" /> | ||
'''MAACKIA AMURENSIS LEUKOAGGLUTININ (LECTIN) WITH SIALYLLACTOSE'''<br /> | '''MAACKIA AMURENSIS LEUKOAGGLUTININ (LECTIN) WITH SIALYLLACTOSE'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Seeds from the legume tree Maackia amurensis contain two lectins that can | + | 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. |
==About this Structure== | ==About this Structure== | ||
| - | 1DBN is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Maackia_amurensis Maackia amurensis] with NAG, CA and MN as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1DBN is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Maackia_amurensis Maackia amurensis] with <scene name='pdbligand=NAG:'>NAG</scene>, <scene name='pdbligand=CA:'>CA</scene> and <scene name='pdbligand=MN:'>MN</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DBN OCA]. |
==Reference== | ==Reference== | ||
| Line 24: | Line 24: | ||
[[Category: sialyllactose]] | [[Category: sialyllactose]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:14:58 2008'' |
Revision as of 10:14, 21 February 2008
|
MAACKIA AMURENSIS LEUKOAGGLUTININ (LECTIN) WITH SIALYLLACTOSE
Overview
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.
About this Structure
1DBN is a Single protein structure of sequence from Maackia amurensis with , and as ligands. Full crystallographic information is available from OCA.
Reference
An unusual carbohydrate binding site revealed by the structures of two Maackia amurensis lectins complexed with sialic acid-containing oligosaccharides., Imberty A, Gautier C, Lescar J, Perez S, Wyns L, Loris R, J Biol Chem. 2000 Jun 9;275(23):17541-8. PMID:10747930
Page seeded by OCA on Thu Feb 21 12:14:58 2008
Categories: Maackia amurensis | Single protein | Gautier, C. | Imberty, A. | Lescar, J. | Loris, R. | CA | MN | NAG | Carbohydrate binding | Plant lectin | Sialyllactose
