CONVERSION OF GALNAC-BETA(1-4)GLCNAC-BETA-OME INTO GALNAC-BETA(1-4)-[FUC-ALPHA(1-3)]GLCNAC-BETA-OME USING HUMAN-MILK ALPHA-3 4-FUCOSYL-TRANSFERASE - SYNTHESIS OF A NOVEL TERMINAL ELEMENT IN GLYCOPROTEIN GLYCANS/

Incubation of GalNAcbeta(1-4)GlcNAcbeta-OMe with GDP-Fuc in the presen ce of human milk alpha3/4-fucosyltransferase resulted in the formation of GalNAcbeta(1-4)[Fucalpha(1-3)]GlcNAcbeta-OMe. Under conditions tha t led to complete alpha3-fucosylation of Galbeta(1-4)GlcNAcbeta-OEt, G alNAcbeta(1-4)GlcNAcbeta-OMe was fucosylated for more than 85%. For th e identification of the isolated fucosylated products one- and two-dim ensional H-1-NMR spectroscopy was applied. In vacuo molecular dynamics simulations of Galbeta(1-4)[Fucalpha(1-3)]GlcNAcbeta-OEt and GalNAcbe ta(1-4)[Fucalpha(1-3)]GlcNAcbeta-OMe using the CHARMm based force fiel d CHEAT, demonstrated only small differences between the conformations of these compounds. This illustrates the minor conformational influen ce of the substituent at C-2', i.e. a hydroxyl function versus a N-ace tyl group.