1w8h

[[Image:1w8h.gif|left|200px]]<br /><applet load="1w8h" size="350" color="white" frame="true" align="right" spinBox="true"

caption="1w8h, resolution 1.75&Aring;" />

'''STRUCTURE OF PSEUDOMONAS AERUGINOSA LECTIN II (PA-IIL) COMPLEXED WITH LEWISA TRISACCHARIDE'''<br />

==Overview==

One of the mechanisms contributing to the protection by breast-feeding of the newborn against enteric diseases is related to the ability of human milk oligosaccharides to prevent the attachment of pathogenic bacteria to the duodenual epithelium. Indeed, a variety of fucosylated oligosaccharides, specific to human milk, form part of the innate immune system. In the present study, we demonstrate the specific blocking of PA-IIL, a fucose-binding lectin of the human pathogen Pseudomonas aeruginosa, by milk oligosaccharides. Two fucosylated epitopes, Lewis a and 3-fucosyl-lactose (Lewis x glucose analogue) bind to the lectin with dissociation constants of 2.2x10(-7) M and 3.6x10(-7) M respectively. Thermodynamic studies indicate that these interactions are dominated by enthalpy. The entropy contribution is slightly favourable when binding to fucose and to the highest-affinity ligand, Lewis a. The high-resolution X-ray structures of two complexes of PA-IIL with milk oligosaccharides allow the precise determination of the conformation of a trisaccharide and a pentasaccharide. The different types of interaction between the oligosaccharides and the protein involve not only hydrogen bonding, but also calcium- and water-bridged contacts, allowing a rationalization of the thermodynamic data. This study provides important structural information about compounds that could be of general application in new therapeutic strategies against bacterial infections.

 

==About this Structure==

1W8H is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_aeruginosa Pseudomonas aeruginosa] with <scene name='pdbligand=CA:'>CA</scene>, <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Known structural/functional Site: <scene name='pdbsite=AC1:Gol+Binding+Site+For+Chain+D'>AC1</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1W8H OCA].

 

==Reference==

Structural basis for the interaction between human milk oligosaccharides and the bacterial lectin PA-IIL of Pseudomonas aeruginosa., Perret S, Sabin C, Dumon C, Pokorna M, Gautier C, Galanina O, Ilia S, Bovin N, Nicaise M, Desmadril M, Gilboa-Garber N, Wimmerova M, Mitchell EP, Imberty A, Biochem J. 2005 Jul 15;389(Pt 2):325-32. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=15790314 15790314]

[[Category: Bovin, N.]]

[[Category: Budova, M.]]

[[Category: Desmadril, M.]]

[[Category: Dumon, C.]]

[[Category: Galanina, O.]]

[[Category: Gautier, C.]]

[[Category: Gilboa-Garber, N.]]

[[Category: Ilia, S.]]

[[Category: Imberty, A.]]

[[Category: Mitchell, E P.]]

[[Category: Nicaise, M.]]

[[Category: Perret, S.]]

[[Category: Sabin, C.]]

[[Category: Wimmerova, M.]]