Improvement of the transfucosylation activity of α-L-fucosidase from Thermotoga maritima for the synthesis of fucosylated oligosaccharides in the presence of calcium and sodium.

The influence of CaCl and NaCl in the hydrolytic activity and the influence of CaCl in the synthesis of fucosylated oligosaccharides using α-L-fucosidase from Thermotoga maritima were evaluated. The hydrolytic activity of α-L-fucosidase from Thermotoga maritima displayed a maximum increase of 67% in the presence of 0.8 M NaCl with water activity (a) of 0.9672 and of 138% in the presence of 1.1 M CaCl (a 0.9581). In addition, the hydrolytic activity was higher when using CaCl compared to NaCl at a of 0.8956, 0.9581 and 0.9672. On the other hand, the effect of CaCl in the synthesis of fucosylated oligosaccharides using 4-nitrophenyl-fucose as donor substrate and lactose as acceptor was studied. In these reactions, the presence of 1.1 M CaCl favored the rate of transfucosylation, and improved the yield of synthesis duplicating and triplicating it with lactose concentrations of 58 and 146 mM, respectively. CaCl did not significatively affect hydrolysis rate in these reactions. The combination of the activating effect of CaCl, the decrement in a and lactose concentration had a synergistic effect favoring the synthesis of fucosylated oligosaccharides.