101 results about "Sialic acid aldolase" patented technology

The present invention describes methods and processes for the production of proteins, particularly glycoproteins, by animal cell or mammalian cell culture, illustratively, but not limited to, fed-batch cell cultures. The methods comprise feeding the cells with D-galactose, preferably with feed medium containing D-galactose, preferably daily, to sustain a sialylation effective level of D-galactose in the culture for its duration, thus increasing sialylation of the produced proteins. The methods can also comprise at least two temperature shifts performed during the culturing period, in which the temperature is lower at the end of the culturing period than at the time of initial cell culture. The cell culture processes of the invention involving two or more temperature shifts sustain a high cell viability, and can allow for an extended protein production phase. The methods can also comprise the delayed addition of polyanionic compound at a time after innoculation. Supplementation of the cultures with D-galactose, preferably in a feed medium, to sustain galactose at sialylation effective levels in the cultures until the end of a culture run reverses a decline in sialylation that accompanies culture scale up, and is advantageous for large scale culturing processes.

Culture media comprising manganese and methods of culturing cells to improve sialylation and glycosylation of glycoproteins are provided.

A novel N-acetyl-5-N,4-O-carbonyl-protected dibutyl sialyl phosphate donor for sialylation of both primary and sterically hindered secondary acceptors to prepare sialosides with high yield and α-selectivity is disclosed. Methods for making disaccharide building blocks comprising α(2→3), α(2→6), α(2→8), α(2→8) / α(2→9) alternate, and α(2→9) sialosides are provided. methods for one-pot synthesis of complex sialosides are disclosed. Libraries of sialosides and methods for using the libraries for detection and receptor binding analysis of surface glycoproteins or pathogens and cancer cells are disclosed. Methods for distinguishing between hemagglutinin (HA) from various strains of influenza are provided.

The present invention relates to a method for the large scale in vivo synthesis of sialylated oligosaccharides, culturing a microorganism in a culture medium, optionally comprising an exogenous precursor such as lactose, wherein said microorganism comprises heterologous genes encoding a CMP-Neu5Ac synthetase, a sialic acid synthase, a GlcNAc-6-phosphate 2 epimerase and a sialyltransferase, and wherein the endogenous genes coding for sialic acid aldolase (NanA) and for ManNac kinase (NanK) have been deleted or inactivated. The invention also relates to these micoorganisms which are capable of producing internally activated sialic acid.

The present invention provides compositions and methods for the production of glycoproteins with enhanced sialylation. In particular, the invention provides cell lines comprising disrupted sialidase expression and methods of using the cell lines to produce glycoproteins with enhanced sialylation.

Methods for producing and / or propagating virus particles that are present in a virus isolate obtained from an infected subject by contacting a host cell with a virus particle and culturing the cell under conditions conducive to propagation of the virus particle are disclosed. A method for selective propagation of a set of virus particles which have an affinity for receptors comprising a specific glycosylation residue are further disclosed. Immortalized human embryonic retina cells comprising a nucleic acid sequence encoding an adenoviral E1A protein integrated into the genome of the cells and a nucleic acid sequence encoding an enzyme involved in post-translational modification of proteins, wherein said nucleic acid sequence encoding the enzyme involved in post-translational modification of proteins is under control of a heterologous promoter are further disclosed. Methods for production of recombinant proteins from such cells and obtaining such recombinant proteins having increased sialylation are also described.

Two Hepatitis C Virus envelope proteins (E1 and E2) are expressed without sialylation. Recombinant expression of these proteins in lower eukaryotes, or in mammalian cells in which terminal glycosylation is blocked, results in recombinant proteins which are more similar to native HCV glycoproteins. When isolated by GNA lectin affinity, the E1 and E2 proteins aggregate into virus-like particles.