Characterization of a core alpha1-->3-fucosyltransferase from the snail Lymnaea stagnalis that is involved in the synthesis of complex-type N-glycans.
We have identified a core alpha1-->3-fucosyltransferase activity in the albumin and prostate glands of the snail Lymnaea stagnalis. Incubation of albumin gland extracts with GDP-[(14)C]Fuc and asialo/agalacto-glycopeptides from human fibrinogen resulted in a labeled product in 50% yield. Analysis of the product by 400 MHz (1)H-NMR spectroscopy showed the presence of a Fuc residue alpha1-->3-linked to the Asn-linked GlcNAc. Therefore, the enzyme can be identified as a GDP-Fuc:GlcNAc (Asn-linked) alpha1-->3-fucosyltransferase. The enzyme acts efficiently on asialo/agalacto-glycopeptides from both human fibrinogen and core alpha1-->6-fucosylated human IgG, whereas bisected asialo/agalacto-glycopeptide could not serve as an acceptor. We propose that the enzyme functions in the synthesis of core alpha1-->3-fucosylated complex-type glycans in L. stagnalis. Core alpha1-->3-fucosylation of the asparagine-linked GlcNAc of plant- and insect-derived glycoproteins is often associated with the allergenicity of such glycoproteins. Since allergic reactions have been reported after consumption of snails, the demonstration of core alpha1-->3-fucosylation in L. stagnalis may be clinically relevant.
van Tetering
A
A
Department of Medical Chemistry, Vrije Universiteit, Van der Boechorststraat 7, 1081 BT, Amsterdam, The Netherlands.
Schiphorst
W E
WE
van den Eijnden
D H
DH
van Die
I
I
D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D005340:Fibrinogen / Q000378:metabolism; D005512:Food Hypersensitivity / Q000209:etiology; D005647:Fucosyltransferases / Q000302:isolation & purification* / Q000378:metabolism; D006020:Glycopeptides / Q000378:metabolism; D006023:Glycoproteins / Q000737:chemistry / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism; D008195:Lymnaea / Q000201:enzymology* / Q000276:immunology; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000096:biosynthesis* / Q000737:chemistry / Q000276:immunology
D006020:Glycopeptides; D006023:Glycoproteins; D007074:Immunoglobulin G; D011134:Polysaccharides; D005340:Fibrinogen; D005647:Fucosyltransferases; C031692:galactoside 3-fucosyltransferase