Fucosyltransferase activities

The presence of three separate, fucosyltransferase activities in human milk was confirmed, and their pH optima and substrate requirements were defined by use of simple oligosaccharides of known structure.235 It was demonstrated that increased affinity for each of... 

Differences in fucolipid content as between normal and transformed cells, and changes on ontogenesis, have already been discussed, and these effects are presumably due to variations in fucosyltransferase activities, with possible specificity differences, namely, a-(l— 2) to Gal or (1— 3 or 4) to GlcNAc. However, the enzymes involved in these cells have not yet been separated and purified, and information on the separate enzyme-activities involved is almost nonexistent. 

Different glycolipid fucosyltransferase activities have been reported (32,55,58) to catalyze the addition of fucose to position C-2 of the terminal D-galactose and position C-3 of the internal N-acetylglucosamine of nLcOse4Cer to form blood group H or human tumor-specific lipid (10). Incorporation of fucose into GgOse4Cer was also reported recently by Taki et al. 

Glycolipid Fucosyltransferase Activities in Mouse and Human Tumor Cells... 

Rabina J, Smithers N, Britten CJ, Renkonen R. A time-resolved immunofluorometric method for the measurement of sialyl Lewis x-synthesizing alphal,3-fucosyltransferase activity. Anal. Biochem. 1997 246 71-78. 

The starting hypothesis that amphibian egg jellies could be a good source of carbohydrates has been shown to be correct. Moreover, the tissues of the animals and in particular the oviducts could also be the source of new and specific glycosyltransferases. The structures listed in Figs. 1-8 allow us to speculate about the activity levels and specificities of transferases in the glycosylation process of oviducal mucins. In fact, referring only to the fucosyltransferase activities, a minimum of six enzymes such as Kdn (al-4)FucT, Fuc(al-4)Kdn (al-2)FucT, Fuc(al-4)Kdn (al-3)FucT, Kdn (al-... 

The a-2- and a-3-L-fucosyltransferase activities of human cells and plasma are inhibited by A -ethylmaleimide, but activities are restored by treatment with dithiothreitol, indicating the necessity of a free thiol group for activity. 

L-Fucosyltransferase activity has been demonstrated in rat ascites hepatoma cells and this enzyme catalyses the addition of L-fucose residues to asialo-G to form an L-fucolipid, in the presence of a detergent with the structure (26). The lipid co-chromatographed with authentic blood-group H-active L-fucolipid. The L-fucosyltransferase activity was highly specific for asialo-G i. ... 

A study of common ABH blood donors, and rare Bombay and Para-bombay individuals, has shown the presence of 2-a-L-fucosyltransferase activity in human sera and erythrocyte membranes." ... 

Yamada N, Chung YS, Takatsuka S, Arimoto Y, Sawada T, Dohi T, Sowa M. Increased sialyl Lewis A expression and fucosyltransferase activity with acquisition of a high metastatic capacity in a colon cancer cell line. Br J Cancer 1994 76 582 587. 

The original nomenclature for the various isoforms of fucosyltransferases, based upon the order in which the genes were isolated, was established by Pamela Stanley [1] and further extended by John Lowe. FucT I and II were used to designate fucosyltransferases activities found in the lectin-resistant CHO cell lines LECH and LEC12 the next five fucosyltransferases identified were human a3,4-fucosyl-transferases whose genes have been cloned (FucT III to VII) [2-8]. 

The FucT V and VI, are found in the plasma, and they catalyze the formation of Fucal,3GlcNAc linkages and produce Le and sLe structures. High expression levels of these enzymes have also been identified in neoplastic tissues, especially in cancers of the lung [41]. The levels of a3-fucosyltransferase activity in plasma are also increased in chronic liver diseases, such as hepatitis, cirrhosis and hepatocellular carcinoma. Indeed, quantitation of this fucosyltransferase activity in plasma can be used as indicator of these diseases [42]. 

Even though some of the protein is secreted, the secreted molecules represent only a small fraction of the fucosyltransferase activity in plasma. This enzyme can fuco-... 

T. Hada, K. Fukui, M. Ohno, S. Akamatsu, S. Yazawa, K. Enomoto, K. Yamaguchi, Y. Matsuda, Y. Amuro, N. Yamanaka, Increased plasma alpha (l- 3)-L-fucosyltransferase activities in patients with hepatocellular carcinoma, Glycoconj J, (1995), 12, 627-31. 

C.H. Hokke, A.P. Neeleman, C.A.M. Koeleman and D.H. Van den Eijnden, Identification of an a3-fucosyltransferase and a novel a2-fucosyltransferase activity in cercariae of the schistosome Trichobilharzia ocellata—Biosynthesis of the Fucal- 2Fucal 3[Gal(NAc)pi—>4]GlcNAc sequence. Glycobiology, 1998, 8, 393-406. 

A. Faik, C. Chileshe, J. Sterling, G. Maclachlan. Xyloglucan galactosyl- and fucosyltransferase activities from pea microsomes. Plant Physiol, 1997, 114, 245-254... 

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