Patent ID: 7955825

Claim:
A process for producing CMP-N-acetylneuraminic acid (CMP-NeuAc), comprising: i) culturing Escherichia coli cells which has been transformed with both the DNA encoding N-acetylglucosamine-6-phosphate 2-epimerase (GlcNAc-6P 2-epimerase) and the DNA encoding N-acetylneuraminic acid synthase (NeuAc synthase) and as the result of being transformed said Escherichia coli cells exhibit the activities of N-acetylglucosamine-6-phosphate 2-epimerase (GlcNAc-6P 2-epimerase) and N-acetylneuraminic acid synthase (NeuAc synthase) in a medium, ii) adding a phosphate buffer of pH 8.0, containing baker's yeast cells, CMP, N-acetylglucosamine (GlcNAc), magnesium, xylene, glucose, and CMP-N-acetylneuraminic acid synthase (CMP-NeuAc synthase) to said cultured cells to provide a reaction mixture, and iii) allowing the reaction to proceed by stirring the mixture for 72 hours at 28° C. and producing CMP-N-acetylneuraminic acid (CMP-NeuAc), wherein the process does not require adding ATP.