Disclosed herein are genetically modified microorganisms and related methods for the enhanced production and export of oligosaccharides. The microorganisms described herein express major facility superfamily proteins such as CDT-1, which allows for the export of oligosaccharides. Variants of CDT-1 exhibit higher activity regarding oligosaccharide export. The microorganisms described herein express formation enzymes for the production of oligosaccharides. Means to export oligosaccharides into the growth medium are provided herein.

The present invention is in the field of a method for production of biomedical compounds by enrichment cultures of microorganisms, and a product obtainable by said methods. The microorganisms are grown in a batch reactor, a continuous reactor, a semi-continuous reactor, such as a Nereda® reactor.

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.

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.

Methods for removing heavy metals from contaminated water including contacting contaminated water with polysaccharides from N. meningitides serotypes B and W; a fusion gene product and fusion enzyme including silica acid synthase and CMP sialic acid synthetase, and use of the fusion enzyme in a simplified process to make CMP Sialic acid and derivatives thereof. Use of CMP Sialic acid and derivatives thereof to remove heavy metals from contaminated water.

Methods for removing heavy metals from contaminated water including contacting contaminated water with polysaccharides from N. meningitides serotypes B and W; a fusion gene product and fusion enzyme including silica acid synthase and CMP sialic acid synthetase, and use of the fusion enzyme in a simplified process to make CMP Sialic acid and derivatives thereof. Use of CMP Sialic acid and derivatives thereof to remove heavy metals from contaminated water.

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

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.