Enzymic synthesis of a new type of fucose-containing glycolipid with fucosyltransferase of rat ascites hepatoma cell, ah 7974f

Abstract

An α-fucosyltransferase activity has been demonstrated in rat ascites hepatoma AH 7974F cells catalyzing the transfer of l-fucose to asialo-GM 1 prepared from bovine brain GM 1 ganglioside to form a fucolipid in the presence of Triton X-100. The radioactive fucolipid was shown to be Fuc-(α 1→ 2)-Gal-(β1 → 3)-GalNAc-(β1→ 4)-Gal-(β1 → 4)-Glc-ceramide from the following results. The radioactive product coincided with authentic blood group H-active fucolipid from AH 7974F cell on thin-layer chromatography. The product formed a precipitation line not only with Ulex europeus lectin but also with eel anti-H serum on agarose gel plates. The terminal 14C-labeled fucose was released by Bacillus fulminans α (1→2)fucosidase as well as Charonia lampas α-fucosidase. The optimum pH value for the incorporation of l-fucose into asialo-GM 1 was 5.8 in sol|cacodylate/HCl buffer. The fucosyltransferase was highly specific for asialo-GM 1.