Lipid-oligosaccharide intermediate of glycoprotein synthesis in Physarum polycephalum

Lipid-linked oligosaccharides were extracted from microplasmodia of Physarum polycephalum grown in the presence of [³H]mannose, [¹⁴C]glucose of N-acetyl[³H]glucosamine. The lipid-oligosaccharide conjugate was purified by column cromatography with DEAE-Sephacel and the oligosaccharide moiety was released by acid hydrolysis. The oligosaccharides were treated with α-mannnosidase and endoglucosaminidase H and the resulting products were analyzed. The results suggest that the lipid-linked oligosaccharide of P. polycephalum is similar, if not identical, to that reported for the lipid-oligosaccharide intermediate in glycoprotein synthesis in animal and plant cells. The biosyenthesis of this oligosaccharide was greatly depressed when the plasmodia underwent differentiation to macrocyts.