This Invention discloses a method for production of N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt by microbial fermentation. The method is intended to manufacture N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt in higher efficiency and higher yield, by expression of vitreoscilla hemoglobin in microorganism.

The invention relates to an isolated nucleic acid molecule comprising at least one promoter that is active in fungal cells of the trichoderma species, wherein a nucleic acid sequence encoding an N-acetylglucosamine-2-epimerase and/or an N-acetylneuraminic acid synthase is operatively bound to each promoter. The at least one promoter that is active in fungal cells is a constitutive promoter.

The invention discloses a genetically engineered bacterium and its application in the preparation of sialyllactose. The genetically engineered bacterium has an N-acetylneuraminic acid biosynthesis pathway, includes multiple copies of a gene neuB for encoding sialic acid synthase, and the gene neuB is initiated for expression by a strong promoter. Using the genetically engineered bacteria of the invention to produce sialyllactose has the advantages of high yield and low overall cost.

An object of the present invention is to provide a microorganism having an ability to produce NeuAc and/or a NeuAc-containing carbohydrate, and a method for producing NeuAc and/or the NeuAc-containing carbohydrate more efficiently by the microorganism. The present invention relates to a microorganism which has an ability to produce NeuAc and/or a NeuAc-containing carbohydrate and whose enterobacterial common antigen (ECA) biosynthesis pathway is blocked, and a method for producing NeuAc and/or the NeuAc-containing carbohydrate using the microorganism.

Mammalian milk oligosaccharides (MMO) are produced in plants engineered to express recombinant MMO biosynthetic pathways.

Provided herein are genetically modified yeast cells capable of producing one or more human milk oligosaccharides (HMOs) and methods of making such cells. The yeast cells are engineered to comprise a heterologous nucleic acid encoding a transporter protein and one or more heterologous nucleic acids that encode enzymes of a HMO biosynthetic pathway. Also provided are fermentation compositions including the disclosed genetically modified yeast cells, and related methods of producing and recovering HMOs generated by the yeast cells.

Provided herein are genetically modified yeast cells capable of producing one or more human milk oligosaccharides (HMOs) and methods of making such cells. The yeast cells are engineered to comprise a heterologous nucleic acid encoding a transporter protein and one or more heterologous nucleic acids that encode enzymes of a HMO biosynthetic pathway. Also provided are fermentation compositions including the disclosed genetically modified yeast cells, and related methods of producing and recovering HMOs generated by the yeast cells.