Patent ID: 11920173
Assignee: CHR. HANSEN HMO GMBH
Field: Biotechnology (Chemistry)
Classification: CPC C  A | IPC A  C

Claim 0:
1. A method for producing N-acetylneuraminic acid (Neu5Ac) by fermentation using a non-naturally-occurring microorganism able to produce Neu5Ac, the method comprising:
a) providing a non-naturally-occurring microorganism which is capable of producing Neu5Ac, wherein said non-naturally-occurring microorganism possesses a sialic acid biosynthesis pathway comprising at least one heterologous enzyme, wherein the naturally occurring sialic acid catabolic pathway of the microorganism has been disabled, wherein at least one phosphoenolpyruvate: sugar phosphotransferase system for the import of a saccharide that is not used as a carbon source during fermentative production of Neu5Ac has been disabled, and wherein the microorganism can utilize an exogenous carbon source present in a fermentation broth as a sole carbon source without using a phosphoenolpyruvate:sugar phosphotransferase system for the acquisition of said exogenous carbon source, and wherein the sialic acid biosynthesis pathway comprises the at least one heterologous enzyme selected from the group consisting of glutamine-fructose-6-phosphate aminotransferase, glucosamine-6-phosphate N-acetyltransferase, N-acetylglucosamine 2-epimerase, N-acetylneuraminic acid synthase, and a sugar phosphatase of the haloacid dehydrogenase (HAD)-like superfamily; and
b) cultivating the non-naturally-occurring microorganism in the fermentation broth and under conditions permissive for the non-naturally-occurring microorganism to produce Neu5Ac.