abstract |
A single reaction vessel process for the synthesis of a sialylated galactoside is disclosed. The synthesis utilizes a beta -galactosidase to catalyze the reaction of a galactose-containing substrate and an acceptor to form a new galactosyl glycoside that is then sialylated using a cyclic multienzyme synthesis system to form CMP-sialic acid that sialylates the formed galactosyl glycoside in the presence of an alpha -sialyltransferase. The value of Km/Vmax for the formed galactosyl glycoside as a substrate for the alpha -sialyltransferase is less than one-third the Km/Vmax value for the galactose-containing substrate for that alpha -sialyltransferase. |