Identification of a GDP-Fuc:Gal beta 1-3GalNAc-R (Fuc to Gal) alpha 1-2 fucosyltransferase and a GDP-Fuc:Gal beta 1-4GlcNAc (Fuc to GlcNAc) alpha 1-3 fucosyltransferase in connective tissue of the snail Lymnaea stagnalis.
Connective tissue of the freshwater pulmonate Lymnaea stagnalis was shown to contain fucosyltransferase activity capable of transferring fucose from GDP-Fuc in alpha 1 -2 linkage to terminal Gal of type 3 (Gal beta 1-3GalNAc) acceptors, and in alpha 1-3 linkage to GlcNAc ot type 2 (Gal beta 1-4GlcNAc) acceptors. The alpha 1-2 fucosyltransferase was active with Gal beta 1-3GalNAc beta 1-OCH2CH=CH2 (Km = 12mM, V(max) = 1.3 mUml-1) and Gal beta 1-3GalNAc (km =20 mM, V(max) = 2.1 mUml-1), whereas the alpha 1-3 fucosyltransferase was active with Gal beta 1-4GlcNAc (Km = 23 mM, V(max) = 1.1 mUml-1). The products formed from from Gal beta 1-3GalNAc beta 1-OCH2CH=CH2 and Gal beta 1-4GlcNAc were purified by high performance liquid chromatography, and identified by 500 MHz 1H-NMR spectroscopy and methylation analysis to be Fucalpha1-2Gal beta 1-3GalNAc beta 1-OCH2CH=CH2 and Gal beta 1-4(Fucalpha1-3)GlcNAc, respectively. Competition experiments suggest that the two fucosyltransferase activities are due to two distinct enzymes.
Mulder
H
H
Bijvoet Center, Department of Bio-Organic Chemistry, Utrecht University, The Netherlands.
Schachter
H
H
Thomas
J R
JR
Halkes
K M
KM
Kamerling
J P
JP
Vliegenthart
J F
JF
D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D003238:Connective Tissue / Q000201:enzymology; D005647:Fucosyltransferases / Q000378:metabolism*; D007700:Kinetics; D008195:Lymnaea / Q000201:enzymology*; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry / Q000378:metabolism; D013379:Substrate Specificity; D000097631:Galactoside 2-alpha-L-fucosyltransferase
D005647:Fucosyltransferases; D009844:Oligosaccharides; D000097631:Galactoside 2-alpha-L-fucosyltransferase; C031692:galactoside 3-fucosyltransferase