The study of the substrate specificity of rat brain fucosyltransferase using synthetic acceptors

The substrate specificity of fucosyltransferase (FT) from rat forebrain and cerebellum was studied using synthetic accepters. Of 16 accepters tested, only those containing the Gal beta 1-4GlcNAc beta 1-R fragment were subject ed to enzymic fucosylation. The isomer with a 1-3 bond as well as lactose a nd oligosaccharides with an additional Neu5Ac residue attached to Gal or a Fuc residue attached to GlcNAc were not fucosylated whereas Fuc alpha 1-2Ga l beta 1-4GlcNAc displayed the same substrate properties as Gal beta 1-4Glc NAc. FT from cerebellum and forebrain was shown to have the specificity sim ilar to that of mammalian FT IV. The activity of the cerebellum FT with all types of substrates was higher than that of FT isolated from forebrain, th e specificity profiles being similar.