This disclosure relates to glycoengineering, and methods of utilizing glycoengineering for various therapeutic purposes.

This disclosure is in the technical field of synthetic biology and metabolic engineering. More particularly, this disclosure is in the technical field of cultivation or fermentation of metabolically engineered cells. This disclosure describes a cell metabolically engineered for production of a mixture of at least three different sialylated oligosaccharides. Furthermore, this disclosure provides a method for the production of a mixture of at least three different sialylated oligosaccharides by a cell as well as the purification of at least one of the sialylated oligosaccharides from the cultivation.

The present invention is in the technical field of synthetic biology and metabolic engineering. More particularly, the present invention is in the technical field of metabolically engineered cells and use of said cell in a cultivation, preferably a fermentation. The present invention describes a cell for the production of a compound. The cell comprises a pathway for the production of the compound, which can be a disaccharide, oligosaccharide and/or a Neu(n)Ac-containing bioproduct, wherein (n) is 4, 5, 7, 8 or 9 or a combination thereof. The cell is metabolically engineered for enhanced synthesis of acetyl-Coenzyme A. The invention also resides in a method of producing such compound by cultivation, preferably a fermentation, with such a cell.

Modified Fc regions of antibodies and antibody fragments, both human and humanized, and having enhanced stability and efficacy, are provided. Fc regions with core fucose residues removed, and attached to oligosaccharides comprising terminal sialyl residues, are provided. Antibodies comprising homogeneous glycosylation of Fc regions with specific oligosaccharides are provided. Fc regions conjugated with homogeneous glycoforms of monosaccharides and trisaccharides, are provided. Methods of preparing human antibodies with modified Fc using glycan engineering, are provided.

The present invention relates to a process for the enzymatic modification of a glycoprotein. The process comprises the step of contacting a glycoprotein comprising a glycan comprising a terminal GlcNAc-moiety, in the presence of glycosyltransferase that is, or is derived from, a ?-(1,4)-N-acetylgalactosaminyltransferase, with a non-natural sugar-derivative nucleotide. The non-natural sugar-derivative nucleotide is according to formula (3): ##STR00001##
wherein A is selected from the group consisting of N.sub.3, C(O)R.sup.3, (CH.sub.2).sub.iC?CR.sup.4, SH, SC(O)R.sup.8, SC(O)OR.sup.8, SC(S)OR.sup.8, F, Cl, Br I, OS(O).sub.2R.sup.5, terminal C.sub.2-C.sub.24 alkenyl groups, C.sub.3-C.sub.5 cycloalkenyl groups, C.sub.4-C.sub.8 alkadienyl groups, terminal C.sub.3-C.sub.24 allenyl groups and amino groups. The invention further relates to a glycoprotein obtainable by the process according to the invention, to a bioconjugate that can be obtained by conjugating the glycoprotein with a linker-conjugate, and to ?-(1,4)-N-acetylgalactosaminyltransferases that can be used in preparing the glycoprotein according to the invention.

It is intended to develop and provide a technique of conveniently allowing a transgenic silkworm by itself and at an individual level to produce a recombinant protein having a mammalian-type sugar chain sialic acid attached thereto, without the need of a baculovirus expression system or oral and transdermal administration of sialic acid. An expression vector was developed which can induce the expression of a mammalian-type glycosylation-related gene group only in a silk gland such that the recombinant protein modified with the mammalian-type sugar chain has no adverse effect on the silkworm itself. A transgenic silkworm harboring the expression vector was prepared.

This invention relates to a method of producing one or more human milk oligosaccharides (HMOs), in particular LNT and/or LNnT, in a genetically engineered cell comprising an enhanced oligosaccharide transport capability. The genetically modified cell comprises a series of genetic modification which enable the production of one or more HMO(s), and a series of genetic modification that enhances the transport of lactose and produced HMO(s).

Modified Fc regions of antibodies and antibody fragments, both human and humanized, and having enhanced stability and efficacy, are provided. Fc regions with core fucose residues removed, and attached to oligosaccharides comprising terminal sialyl residues, are provided. Antibodies comprising homogeneous glycosylation of Fc regions with specific oligosaccharides are provided. Fc regions conjugated with homogeneous glycoforms of monosaccharides and trisaccharides, are provided. Methods of preparing human antibodies with modified Fc using glycan engineering, are provided.

Disclosed are a construction method and application of a microorganism capable of realizing high production of lacto-N-neotetraose, belonging to the field of microbial genetic engineering. Coding genes of ?-1,3-acetyl glucosamine transferase, ?-1,4-galactosyl transferase and/or UDP-glucose 4 epimerase are over-expressed on the basis of a strain which is previously constructed by the team and is subjected to related-gene knockout, thus enabling the strain to have a synthesis capability of producing the lacto-N-neotetraose. The present disclosure accurately regulates the carbon flux of a metabolic pathway and relieves the metabolic stress by screening the high-efficiency ?-1,4-galactosyl transferase gene and regulating the expression of IgtA, Aa-?-1,4-GalT and galE in a lacto-N-neotetraose synthesis pathway in a combined manner. In a shake flask experiment, the lacto-N-neotetraose production capacity of Escherichia coli is 0.91 g/L. The lacto-N-neotetraose yield in a 3 L fermentation tank reaches 12.14 g/L. Therefore, the microorganism has an industrial application prospect.

This disclosure is in the technical field of synthetic biology and metabolic engineering. More particularly, this disclosure is in the technical field of fermentation of metabolically engineered yeast or fungal cells. This disclosure describes a method for the extracellular production of a di- or oligosaccharide that is derived from UDP-GlcNAc by a yeast or fungal cell as well as the separation of the di- or oligosaccharide from the cultivation. Furthermore, this disclosure provides a metabolically engineered yeast or fungal cell for extracellular production of a di- or oligosaccharide that is derived from UDP-GlcNAc and that is synthesized in the cytosol.