N-acetylgalactosaminyl or N-acetylglucosaminyl transfer using N-acetylglucosaminyl-1-phosphate or N-acetylgalactosaminyl-1-phosphate as precursor and glycosyl-nucleotide regeneration

A process for using N-acetylgalactosamine 1-phosphate (GalNAc-1-P) or N-acetylglucosamine 1-phosphate (GlcNAc-1-P), respectively, to glycosylate an acceptor with GlcNAc or GalNAc, respectively, with recycling of uridine diphosphate that comprises the steps of:

• (a) admixing the following ingredients in an aqueous medium within a single vessel to form an aqueous reaction medium
• (i) a monosaccharide phosphate that is one or the other of GalNAc-1-phosphate or GlcNAc-1-phosphate;
• (ii) one or the other of UDP-GalNAc pyrophosphorylase or UDP-GlcNAc pyrophosphorylase that catalyzes the formation of UDP-GalNAc or UDP-GlcNAc from the monosaccharide phosphate of (i) in the presence of UTP;
• (iii) a glycosyl transferase that is one or the other of a GalNAc or a GlcNAc transferase, the transferase present transferring whichever of GalNAc or GlcNAc is not present as the monosaccharide 1-phosphate of (i);
• (iv) an epimerase that interconverts UDP-GalNAc and UDP-GlcNAc;
• (v) an acceptor for the glycosyl transferase of (iii);
• and
• (vi) a uridine diphosphate recycling system that includes (a) UDP, UTP or both, (b) a phosphate donor, and (c) a kinase to transfer a phosphate group from the phosphate donor to UDP to form UTP, wherein each of the enzymes of (ii), (iii), (iv) and (vi) is present in a catalytic amount;
• and
• (b) maintaining said aqueous reaction medium at a pH value of about 5 to about 10 at a temperature of about zero degrees C. to about 40.degree. C. for a time period sufficient for said acceptor to be glycosylated.