Methods of using a bacterial glcnac-6-p 2'- epimerase to promote sialylation of glycoconjugates

Abstract

The present invention relates to new methods to promote sialylation of glycoconjugates, including recombinant glycoproteins, in glycoconjugate production systems. The invention relates to methods to promote efficient glycoconjugate sialylation in recombinant expression systems, by providing simpler and more economical ways to produce large intracellular pools of sialic acid precursors. The invention is directed to nucleic acids, vectors, and cells harboring vectors comprising nucleic acids encoding enzymes involved in the synthesis of sialic acid precursors, and cells harboring these nucleic acids in combination with nucleic acids encoding glycosyltransferases, including sialyltransferases, to facilitate the production of humanized recombinant glycoproteins in bacterial, fungal, plant, and animal cell expression systems. The engineered cells can be used to produce glycosylated proteins in virally-infected, transiently-transformed, or stably-transformed host cells, including lepidopteran insects and cultured cell lines derived from, andthat can be infected by baculovirus expression vectors.