Efficient one-pot enzymatic synthesis of α-(1→4)-glucosidic disaccharides through a coupled reaction catalysed by Lactobacillus acidophilus NCFM maltose phosphorylase

Lactobacillus acidophilus NCFM maltose phosphorylase (LaMalP) of glycoside hydrolase family 65 catalysed enzymatic synthesis of α-(1→4)-glucosidic disaccharides from maltose and five monosaccharides in a coupled phosphorolysis/reverse phosphorolysis one-pot reaction. Thus phosphorolysis of maltose to β-glucose 1-phosphate circumvented addition of costly β-glucose 1-phosphate for reverse phosphorolysis with different monosaccharide acceptors, resulting in 91%, 89%, 88%, 86% and 84% yield of α-d-glucopyranosyl-(1→4)-N-acetyl-d-glucosaminopyranose [N-acetyl-maltosamine], α-d-glucopyranosyl-(1→4)-d-glucosaminopyranose [maltosamine], α-d-glucopyranosyl-(1→4)-d-mannopyranose, α-d-glucopyranosyl-(1→4)-l-fucopyranose and α-d-glucopyranosyl-(1→4)-d-xylopyranose, respectively, from 0.1 M maltose, 0.5 M N-acetyl glucosamine, 0.1 M glucosamine, 0.1 M mannose, 1 M l-fucose and 0.5 M xylose in 0.2 M phosphate-citrate pH 6.2. These current yields of 0.27–0.34 g of disaccharide products from 10 mL reaction mixtures are easy to scale up and moreover the strategy can be applied to large-scale production of other oligosaccharides from low-cost disaccharides as catalysed by phosphorylases with different substrate specificities.