Glucose starvation alters lipid-linked oligosaccharide biosynthesis in Chinese hamster ovary cells

The effect of glucose deprivation on the synthesis of lipid-linked oligosaccharides by Chinese hamster ovary cells has been studied. When these cells are placed in serum-free Dulbecco's minimal essential medium devoid of glucose, there is a rapid cessation of the synthesis of the usual Glc3Man9GlcNAc2 lipid-linked oligosaccharide and the accumulation of a smaller species with the composition Man9GlcNAc2. This latter compound is the glucosylated and transferred to protein where it is subsequently processed. These findings demonstrate that Chinese hamster ovary cells utilize an alternate glycosylation pathway when deprived of glucose.