Alpha-1,6-linked fucose

However, the major limitation for the use of biopharmaceuticais produced by plants is the glycosylation pattern. Animal and plant N-linked glycosylation patterns are identical in the core structure, but there are differences in the additional sugar residues. Plant N-glycans contain beta 1,2-linked xylose and alpha 1,3-linked fucose residues, whereas the beta 1,4-linked terminal galactose residue, which is typical for animal-derived glycoproteins (e.g., on antibodies) is not present in plants. There is also some evidence that plant-specific residues have immunogenic potential [8, 9]. 

Tretter, V., Altmann, F., Kubelka, V., Marz, L., Becker, W.M. Fucose alpha 1,3-linked to the core region of glycoprotein N-glycans creates an important epitope for IgE from honeybee venom allergic individuals. Int. Arch. Allergy Immunol., 1993, 102, 259-266. 

Faye, L., Gomord, V., Fitchetter-Laine, A. C., Chrispeels, M. J. Affinity pinification of antibodies specific for Asn-linked glycans containing alpha 1,3 fucose or beta 1,2 xylose. Anal Biochem., 1993, 209, 104-108. 

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