Efficient one-pot enzymatic synthesis of alpha-(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 alpha-(1-->4)-glucosidic disaccharides from maltose and five monosaccharides in a coupled phosphorolysis/reverse phosphorolysis one-pot reaction. Thus phosphorolysis of maltose to beta-glucose 1-phosphate circumvented addition of costly beta-glucose 1-phosphate for reverse phosphorolysis with different monosaccharide acceptors, resulting in 91%, 89%, 88%, 86% and 84% yield of alpha-d-glucopyranosyl-(1-->4)-N-acetyl-D-glucosaminopyranose [N-acetyl-maltosamine], alpha-D-glucopyranosyl-(1-->4)-D-glucosaminopyranose [maltosamine], alpha-D-glucopyranosyl-(1-->4)-D-mannopyranose, alpha-D-glucopyranosyl-(1-->4)-L-fucopyranose and alpha-D-glucopyranosyl-(1-->4)-D-xylopyranose, respectively, from 0.1M maltose, 0.5M N-acetyl glucosamine, 0.1M glucosamine, 0.1M mannose, 1M L-fucose and 0.5M xylose in 0.2M 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.