Enzymatic synthesis of N-acetyllactosamine in aqueous-organic reaction media.
Beta-galactosidase from Bacillus circulans was used for the biocatalytic transfer of D-galactose (D-Gal) from o-nitrophenyl-beta-D-galactoside (ONPG) to the O-4 position of 2-acetamido-2-deoxy-D-glucopyranose (D-GlcNAc) forming the disaccharide N-acetyllactosamine (LacNAc, beta-D-Gal-(1 --> 4)-D-GlcNAc). In order to investigate the potential of this biocatalytic synthesis, first the optimal reactant ratio in an aqueous buffer system was determined. On the basis of these standard conditions we then performed reactions in aqueous-organic media applying organic cosolvents of different structure and polarity in various amounts. In this way we received in some cases appreciably better results than without organic cosolvent. The highest obtainable disaccharide yield was 50% in a mixture of 20% (v/v) cyclohexane/80% buffer versus 35% in buffer solution alone.
Franke
J
J
Institute of Biochemistry, University of Technology, Dresden, Germany.
Braun
K
K
Kuhl
P
P
D000606:Amino Sugars / Q000138:chemical synthesis*; D001407:Bacillus / Q000187:drug effects / Q000201:enzymology; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D007202:Indicators and Reagents; D007700:Kinetics; D008969:Molecular Sequence Data; D001616:beta-Galactosidase / Q000737:chemistry
D000606:Amino Sugars; D007202:Indicators and Reagents; C000458:N-acetyllactosamine; D001616:beta-Galactosidase