1989 Volume 35 Issue 6 Pages 413-427
Glycopeptides from the microplasmodia of Physarum polycephalum grown in the presence of [3H]mannose or [3H]glucosamine were characterized by gel-filtration, anion-exchange and lectin-affinity chromatography before and after enzymatic or chemical treatment. Various types of glycopeptide were found in the growing plasmodia as shown by Con A affinity column chromatography, while pulse-labeled precursors were composed mainly of mannose-rich glycopeptides which were sensitive to endo H and α-mannosidase. During the processing of the glycoprotein, the mannose-rich glycopeptides changed to larger glycopeptides which were resistant to endo H and α-mannosidase. These processing reactions of the glycoprotein appeared to be blocked when the plasmodia underwent differentiation to macrocysts.