The present invention provides N-acetyl derivatives of sialic acids, including N-acetyl derivatives of Neu5Ac and Neu5Gc. Methods for preparing related precursors and a variety of sialosides are also disclosed.

Provided herein are host cells capable of producing hybrid oligosaccharides and polysaccharides, wherein said hybrid oligosaccharides and polysaccharides do not comprise a hexose at the reducing end of their first repeat unit. Also provided herein are hybrid oligosaccharides or polysaccharides and bioconjugates which can be produced by the host cells described herein, wherein said bioconjugates comprise a carrier protein linked to a hybrid oligosaccharide or polysaccharide that does not comprise a hexose at the reducing end of its first repeat unit.

Provided herein are host cells capable of producing hybrid oligosaccharides and polysaccharides, wherein said hybrid oligosaccharides and polysaccharides do not comprise a hexose at the reducing end of their first repeat unit. Also provided herein are hybrid oligosaccharides or polysaccharides and bioconjugates which can be produced by the host cells described herein, wherein said bioconjugates comprise a carrier protein linked to a hybrid oligosaccharide or polysaccharide that does not comprise a hexose at the reducing end of its first repeat unit.

The present invention provides protected tetrasaccharides, their process of preparation and their use in the synthesis of oligosaccharides, in particular fragments of O-antigens from Shigella flexneri, for example of serotype 1a, 1b, 2a, 2b, 3a, X, 4a, 4b, 5a, 5b, 7a or 7b.

The present invention provides protected tetrasaccharides, their process of preparation and their use in the synthesis of oligosaccharides, in particular fragments of O-antigens from Shigella flexneri, for example of serotype 1a, 1b, 2a, 2b, 3a, X, 4a, 4b, 5a, 5b, 7a or 7b.

This disclosure provides a method of synthesis of 4′-thioribose NAD+ and analogues thereof, using an efficient chemoenzymatic approach. Also provided are methods of inhibiting the CD38 enzyme and compounds including 4′-thioribose NAD+ and compounds related thereto.

This disclosure provides a method of synthesis of 4′-thioribose NAD+ and analogues thereof, using an efficient chemoenzymatic approach. Also provided are methods of inhibiting the CD38 enzyme and compounds including 4′-thioribose NAD+ and compounds related thereto.

The invention provides compositions and methods for engineering E. coli or other host production bacterial strains to produce fucosylated oligosaccharides, and the use thereof in the prevention or treatment of infection.

Disclosed are methods for the fermentative production of a sialylated saccharide and genetically engineered microbial cells for use in said method, wherein the genetically engineered microbial cells comprise (i) a sialic acid biosynthesis pathway comprising a glucosamine-6-phosphate N-acetyltransferase, (ii) a cytidine 5′-monophospho-(CMP)-N-acetylneuraminic acid synthetase; and (iii) a sialyltransferase, for producing sialylated saccharides, as well as the use of said sialylated oligosaccharides for providing nutritional compositions.

Disclosed are methods for the fermentative production of a sialylated saccharide and genetically engineered microbial cells for use in said method, wherein the genetically engineered microbial cells comprise (i) a sialic acid biosynthesis pathway comprising a glucosamine-6-phosphate N-acetyltransferase, (ii) a cytidine 5′-monophospho-(CMP)-N-acetylneuraminic acid synthetase; and (iii) a sialyltransferase, for producing sialylated saccharides, as well as the use of said sialylated oligosaccharides for providing nutritional compositions.