Glycosylation in vitro of Semliki-Forest-virus and influenza-virus glycoproteins and its suppression by nucleotide-2-deoxy-hexose.
Cell-free enzyme preparations from cultured fibroblasts infected with Semliki forest virus or fowl plague virus (an influenza A virus) incorporate [14C]-mannose into dolichol-phosphate-mannose, lipid-linked oligosaccharides and into endogenous virus-specific glycoproteins. When GDP-2-deoxy-D-[14C]glucose serves as substrate 2-deoxy-D-[14C]glucose is transferred to dolichol phosphate yielding dolichol-monophosphate-2-deoxy-D-[14C]glucose. UDP-2-deoxy-D-[14C]glucose gives rise also to a lipid which, however, is not a polyprenol derivative. The transfer of [14C]mannose to lipid-extractable fractions and glycoproteins in vitro is blocked by GDP-2-deoxy-D-glucose. It can be restored by exogenous dolichol monophosphate only with regard to the formation of dolichol-monophosphate-[14C]mannose-labelled oligosaccharides into glycoproteins. UDP-2-deoxy-D-glucose has no inhibitory effect on transfer reactions of [14C]mannose from GDP-[14C]mannose into various lipid fractions or into glycoprotein. It is concluded therefore, that the inhibition of glycosylation brought about by 2-deoxyglucose in vivo is caused by an interference of its GDP derivative with the formation of a correct lipid-oligosaccharide.
D004288:Dolichol Phosphates / Q000378:metabolism; D006023:Glycoproteins / Q000096:biosynthesis*; D006155:Guanosine Diphosphate Mannose / Q000378:metabolism; D006156:Guanosine Diphosphate Sugars / Q000378:metabolism; D009980:Influenza A virus / Q000378:metabolism*; D007700:Kinetics; D012672:Semliki forest virus / Q000378:metabolism*; D014539:Uridine Diphosphate Sugars / Q000378:metabolism; D014764:Viral Proteins / Q000096:biosynthesis*
D004288:Dolichol Phosphates; D006023:Glycoproteins; D006156:Guanosine Diphosphate Sugars; D014539:Uridine Diphosphate Sugars; D014764:Viral Proteins; D006155:Guanosine Diphosphate Mannose