Fucose residue

The carbohydrate has sites for ionic interaction (clusters of sialic acid or sulphate residues) and also hydrophobic interaction (clusters of hydrophobic methyl groups offered by fucose residues). Sedimentation velocity has been a valuable tool in the selection of appropriate mucoadhesives and in the characterisation of the complexes [ 138-143]. 

The latter was isolated in the form of fully methylated methyl fuco-side, i. e., methyl 2,3,4-trimethyl-a-L-fucoside (XLVII), a compound previously obtained from methylated gum tragacanth.128 The recognition of this particular derivative indicates that the n-fucose residues in part at least must constitute end groups linked glycosidically to the rest of the molecule. The same compound128 was isolated by methylation and... 

Fig. 15.3 Plant and mammalian N-glycans have different structures. As illustrated here, a core structure (in gray) is common to plant and mammalian biantennary complex N-glycans. However, differences in the glycan processing machineries in plants and in mammals result in the absence of sialic acids in the terminal position of the antennae and the presence of a bisecting p (1,2) -xylose and of an a(l,3)-fucose residue in PMPs instead of the a(l,6)-fucose linked to the proximal N-acetylglucos-amine of native mammalian N-glycans.

C5-1 antibody was produced in alfalfa, the glycan component consisted predominantly of a mature oligosaccharide comprising a core a(l,3)-fucose residue, a bisecting P(l,2)-xylose residue and two terminal GlcNAc residues (Fig. 15.4) [6],... 

As displayed in Fig. 4, for this family of proteins, the entropy of binding is either favorable or weakly unfavorable, while the enthalpy of binding is negative, resulting in micromolar affinity. The only exception is a PA-IIL ligand consisting of two fucose residues separated by a flexible linker that... 

Acid-labile linkages of carbohydrates are commonly those of furano-sidic sugar residues or of deoxy monosaccharides.50,63 Consequently, neuraminic acid and fucose residues, which occur as terminal monosaccharides of protein- and lipid-linked glycans, are removed by hydrolysis with a dilute acid. The linkages formed by these two sugar residues can conveniently be differentiated by subjecting a portion of... 

Figure 16. Ball and stick drawing of 2-0-(4-0-sulfo-a-L-fucopyranosyl)-4-0-sulfo-a-L-fucopyranose ("fucobiose") in the < , y = 0 reference conformation as in Fig. 1. Structural characteristics of rigid sulfated fucose residue deduced from energy minimization with MM2 to be reported elsewhere.

The surface in Figure 19 thus clearly represents half the total energy of an interior a-L-fucose residue embedded in a long a-(1 2)-L-fucan helix due to its interactions with the other residues of the chain. 

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