Improvement of Fucosylated Oligosaccharides Synthesis by α-L-Fucosidase from Thermotoga maritima in Water-Organic Cosolvent Reaction System

Abstract

The effects of water activity (a w ), pH, and temperature on transglycosylation activity of α-L-fucosidase from Thermotoga maritima in the synthesis of fucosylated oligosaccharides were evaluated using different water -organic cosolvent reaction systems. The optimum conditions of transglycosylation reaction were the pH range between 7 and 10, and temperature 90-95°C. The addition of organic cosolvent decreased α-L-fucosidase transglycosylation activity in the following order: acetone > dimethyl sulfoxide (DMSO) > acetonitrile (0.51 > 0.42 > 0.18 mM/h). However, the presence of DMSO and acetone enhanced enzyme-catalyzed transglycosylation over hydrolysis as demonstrated by the obtained transglycosylation/hydrolysis rate (r T/H ) values of 1.21 and 1.43, respectively. The lowest r T/H was calculated for acetonitrile (0.59), though all cosolvents tested improved the transglycosylation rate in comparison to a control assay (0.39). Overall, the study allowed the production of fucosylated oligosaccharides in water-organic cosolvent reaction media using α-L-fucosidase from Thermotoga maritima as biocatalyst.