Use of transformed whole yeast cells expressing β-1,4-galactosyltransferase for the synthesis of N-acetyllactosamine

We report the use of transformed whole yeast cells for the synthesis of N-acetyllactosamine (LacNAc), which is the core-disaccharide of the anti-inflammatory agent Sialyl-LewisX. Transformed whole yeast cells, which carry plasmids for the heterologous expression of a soluble human b-1,4-galactosyltransferase (GalT), proved to be a suitable catalyst for the synthesis of LacNAc by employing multi-enzyme-systems. This convenient use of the recombinant enzyme, taken together with the high availability of the transformed yeast through fermentation technology, will provide sufficient amounts of glycosyltransferase for chemoenzymatic synthesis of oligosaccharides.