Dolichol-dependent protein glycosylation in a deoxy-glucose-resistant baby-hamster-kidney cell line

The formation in vivo of lipid-linked oligosaccharides is inhibited by deoxy-glucose in wild-type BHK cells but not in a cell-line (dGR) selected for resistance towards deoxyglucose. On the other hand, the formation in vitro of lipid-linked oligosaccharides by membranes from dGR (and wild-type) cells is inhibited by GDPdeoxyglucose, the main metabolite responsible for inhibition of protein glycosylation by deoxyglucose. Our results suggest increased pools of GDP mannose and decreased amounts of GDPdeoxyglucose in the mutant cell line. The enlarged ratio of GDPmannose to GDPdeoxyglucose in the dGR cells treated with deoxyglucose is shown to moderate the inhibition of formation of lipid-linked oligosaccharides, and this explains the capacity of the dGR-cells to grow in the presence of deoxyglucose.