Fractionation of mannose-labeled neutral glycopeptides by QAE-Sephadex chromatography.

Mannose-labeled cellular glycopeptides derived from human diploid fibroblasts (KL-2) were separated into two classes by QAE-Sephadex chromatography. High-voltage paper electrophoresis and Sephadex G-50 chromatography were used to characterize the glycopeptides further. At least five distinct neutral fractions were isolated with molecular weights ranging from 1050 to 2000 daltons. A linear gradient of ammonium acetate eluted a heterogeneous population of acidic glycopeptides. The use of QAE-Sephadex enables a single-step fractionation of both neutral and acidic glycopeptides on one column. The technique appears to be sensitive enough to distinguish growth-dependent alterations between growing and non-growing cells.