Lectins L-fucose-binding

O-methylation on the basis of structural similarities between D- and L-fucose derivatives as noted in three-dimensional models. Thus, a similarity in profile and in regions of low hydrogen-bonding capability is evident between 2-O-methyl-D-fucose and L-fucose, if the latter is rotated 180° about its horizontal axis. This phenomenon is even more apparent in the binding of D-fucose derivatives to the L-fucose-binding lectin of the eel167 (see Section VI,1). 

Ulex eurnpaeus II (gorse see also L-fucose-binding lectins)... 

Ulex europaeus seeds contain two agglutinins an L-fucose-binding lectin (U. europaeus I, UFA I) and U. europaeus II (UEA II), which is most potently Inhibited by V-acetylated chitodextrins and L-Fuc(al-2)Gal( 3l-4)GlcNAc. 

UEA I has been sequenced and shown to exhibit extensive homology with many other legume lectins, but not with Lotus tetragonolobus, another L-fucose-binding lectin. 

Highly porous and hydrophilic supports have been prepared by co-polymerization of A-tris(hydroxymethyl)methyl acrylamide or A-tris(hydroxymethyl)-methyl methacrylamide with acrylic monomers bearing carboxyl functions, and then treated with 4-aminophenyl a-L-fucoside using a water-soluble carbodi-imide mediator. The support was used for purification of the L-fucose-binding lectin from Ulex europeus. 

It is well known that intestinal M cells have the ability to efficiently transcytose macromolecules and inert particles, which has stimulated researchers to target M cells for oral delivery of macromolecular drugs and particles.26,52 For example, Ulex europaeus 1 (UEAl), a lectin specific for a-L-fucose residues, selectively binds to mouse Peyer s patch M cells.56 It has become apparent that UEAl can be used to target macromolecules to mouse Peyer s patch M cells and to enhance macromolecular... 

Another feature of the eel-serum specificity that is unlike that of other lectins is the existence of anomeric preference only within the L-fucose series.167,674 Thus, a-L-fucopyranosides are two to five times as efficient as inhibitors as their parent compounds, whereas their /3-L-glycosidically linked counterparts have half to one-third the effect. On the other hand, the anomers of methyl 3-O-methyl-D-fucopyranoside are of equivalent activity, being approximately twice as active as the parent saccharide. In the D series, over 90% of the binding energy is evidently accounted for by parts of the sugar molecule other than the anomeric carbon atom and the aglycon. 

There are two lectins of distinct, sugar-binding specificity in Ulex extracts.196,225 Using ethanol fractionation, Flory225 initially discriminated between Ulex I, which is readily inhibited by L-fucose derivatives, and Ulex II, which binds /3-D-glucosides. (A comprehensive discussion of Ulex II purification and properties is presented in Section III,5.) Flory s 50-70% ethanol precipitate enriched in Ulex I, was slightly inhibited by D-arabinose, D-ribose, and D-lyxose, in addition to L-fucose.225 This preparation agglutinated human, epithelial, cheek-cells of secretory individuals only.225... 

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