The disclosure discloses Bacillus subtilis for producing N-acetylneuraminic acid and application thereof, and belongs to the field of genetic engineering. The disclosure optimizes the expression levels of key enzymes in N-acetylneuraminic acid synthesis pathways on genome through promoters of different strength, reduces the protein synthesis pressure caused by the expression of enzymes on cells, and further integrates the three N-acetylneuraminic acids in a same Bacillus subtilis engineering strain. Bacillus subtilis with improved N-acetylneuraminic acid production is obtained, and the production reaches 10.4 g/L at the shake flask level, laying a foundation for further improving the NeuAc production from Bacillus subtilis.

Provided herein, inter alia, are methods, bacteria, nucleic acids, and polypeptides for producing sialylated oligosaccharides.

Provided herein, inter alia, are methods, bacteria, nucleic acids, and polypeptides for producing sialylated oligosaccharides.

Disclosed herein are methods of expressing UDP-GlcNAc 2-Epimerase/ManNAc Kinase enzyme (GNE) peptide in a cell of a subject comprising: delivering into the cell of the subject an isolated nucleic acid expression construct that comprises a promoter operatively linked to a nucleic acid sequence encoding a GNE peptide or a therapeutically active fragment thereof, wherein the GNE peptide has the amino acid sequence of SEQ ID NO:3, wherein upon the delivering into the cell of the subject, the nucleic acid expression construct initiates expression of the GNE peptide or a therapeutically active fragment thereof. Also disclosed are methods of producing a GNE peptide in a cell comprising infecting the cell with an isolated nucleic acid construct that comprises a promoter operatively linked to a nucleic acid sequence encoding a GNE peptide or a therapeutically active fragment thereof, wherein the GNE peptide has the amino acid sequence of SEQ ID NO:3.

The disclosure discloses Bacillus subtilis for producing N-acetylneuraminic acid and application thereof, and belongs to the field of genetic engineering. The disclosure optimizes the expression levels of key enzymes in N-acetylneuraminic acid synthesis pathways on genome through promoters of different strength, reduces the protein synthesis pressure caused by the expression of enzymes on cells, and further integrates the three N-acetylneuraminic acids in a same Bacillus subtilis engineering strain. Bacillus subtilis with improved N-acetylneuraminic acid production is obtained, and the production reaches 10.4 g/L at the shake flask level, laying a foundation for further improving the NeuAc production from Bacillus subtilis.

The invention relates to composition and methods for expressing UDP-GlcNAc 2-Epimerase/ManNAc Kinase enzyme (GNE) in a living organism. In preferred embodiments, the invention relates to treating disease condition that involves use of therapeutically effective amount of a composition described herein.

The invention relates to composition and methods for expressing UDP-GlcNAc 2-Epimerase/ManNAc Kinase enzyme (GNE) in a living organism. In preferred embodiments, the invention relates to treating disease condition that involves use of therapeutically effective amount of a composition described herein.

Provided herein are genetically modified yeast cells capable of producing one or more human milk oligosaccharides. The yeast cells include one or more heterologous nucleic acids that encode enzymes of a human milk oligosaccharide biosynthetic pathway. The yeast cells do not include a heterologous nucleic acid encoding a fucokinase. Also provided are fermentation compositions including the disclosed genetically modified yeast cells, and related methods of producing and recovering human milk oligosaccharides generated by the yeast cells.

Provided herein, inter alia, are methods, bacteria, nucleic acids, and polypeptides for producing sialylated oligosaccharides.

Compositions for producing glycoengineered proteins, e.g. antibodies, include host cells which lack the ability to produce enzymes that modulate sialic acid metabolic flux.