Fucosyltransferase, fucosylation

Table 4. Substrate specificity of deoxygenated acceptors for a-(l->3/4)fucosyltransferase fucosylation...

To overcome the synthetic and inhibition problems, an integrated recycling system is applied. GTP and Fuc-l-P are transformed by GDP-fucosyl-pyro-phosphorylase to pyrophosphate and the activated donor (GDP-Fuc) [71]. This in turn in the presence of al-3/4-fucosyltransferase fucosylates the acceptor Gal)3l-4GlcNAc at the GlcNAc-3-position or the acceptor Gal)3l-3GlcNAc at the GlcNAc-4-position. The released GDP is phosphorylated to GTP with pyruvate kinase employing the activated phosphate donor phosphenol pyruvate, which in... 

This class of enzymes includes galactoside 3(4)-L-fucosyl-transferase, [EC 2.4.1.65] glycoprotein 6-a-L-fucosyl-transferase [EC 2.4.1.68], galactoside 2-ce-L-fucosyltran-sferase [EC 2.4.1.69], and galactoside 3-fucosyltransferase [EC 2.4.1.152]. 

Galactoside 2-L-fucosyltransferase [EC 2.4.1.69], also known as blood group H a-2-fucosyltransferase, catalyzes the reaction of GDP-L-fucose with /8-D-galacto-syl-R to produce GDP and a-L-fucosyl-l,2-/3-D-galac-tosyl-R. Lactose can also act as the acceptor substrate. 

Fucosyltransferase in pea microsomal preparations also fucosylated exogenously-added xyloglucan acceptors in addition to endogenous primers... 

Several fucosyltransferases have been isolated and used for in vitro synthesis. The Lewis A al,4-fucosyltransferase transfers unnatural fucose derivatives in from their GDP esters [23]. The enzyme al,3-fiicosyltransferase has been used to L-fucosylate the 3-position of the GlcNAc of A-acetyllactosamine and of sialyl a2,3-N-acetyllactosamine [24]. Several acceptor substrates with modifications in the GlcNAc residue could also be... 

M. coturnix ceramide. Intriguingly, fucosylated glycolipids obtained from E. multilocularis were found to possess only short-chain fatty acids with 16 and 18 carbon atoms (mainly 0 6 0 and C18h 0), which might indicate that the (a1-3)-fucosyltransferase involved in the biosynthesis of such compounds requires an acceptor substrate with shorter fatty acids, whereas ((51 -6)-galactosyltransferase from this source obviously accepts all kinds of galacto-sylceramide precursors (Persat et al., 1992). 

Vanzin, G. F., Madson, M., Carpita, N. C., Raikhel, N. V, Keegstra, K., and Reiter, W. D., The mur2 mutant of Arabidopsis thaliana lacks fucosylated xyloglucan because of a lesion in fucosyltransferase AtFUTl. Proc Natl AcadSci USA 2002, 99 (5), 3340-5. 

Fig. 8. Enzymatic fucosylation with integrated cofactor regeneration (Enzymes vi cf. Fig. 2, xi GDP-fucose-pyrophosphorylase, xii al-3/4-fucosyltransferase) [72]... 

Here again, it is as probes that carba-oligosaccharides find their best applications. Compounds 7 and 8 were both submitted to the action of a-(l-3/4)-fucosyltransferase in the presence of GDP-fucose. Only 7 was accepted and fucosylated to give the Lewis analog 9 showing that this enzyme has a different mode of action regarding the synthesis of Lewis s (Scheme 8.3) [16]. 

G. Formation of the fucosyl a 1,3-linkage using txl,3-fucosyltransferase without regeneration of GDP-Fuc 499... 

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