| abstract |
The present disclosure relates to a method for preparing recombinant glycoproteins with high sialic acid content. More specifically, for UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE/MNK) enzyme where point mutation was induced by substituting arginine at position 263 by leucine only or by further substituting arginine at position 266 by glutamine, epimerase activity is constantly maintained, and overexpressed cells thereof experience an increase in intracellular cytidine monophosphate (CMP)-sialic acid content, irrespective of CMP-sialic acid concentration. Particularly, since in an glycoprotein(such as, erythropoietin and thrombopoietin)-producing host cell where point mutationinduced GNE/MNK, human alpha-2,3-sialyltransferase and a CMP-sialic acid transporter gene are simultaneously overexpressed, intracellular content of CMP-sialic acid and sialic acid in glycoprotein increases in cells, overexpression in a host cell producing a sialylated recombinant glycoprotein the three genes above may be useful for preparing glycoprotein with increased sialic acid content. |