Mannose containing glycopeptides of cells derived from human teratocarcinoma (line PA 1)

Abstract

Human teratocarcinoma derived cells, line PA 1, maintained in the undifferentiated state, yielded upon exhaustive pronase digestion unusually large glycopeptides (fraction A), which showed on gel filtration an apparent molecular weight larger than 7400. These glycopeptides derived from whole cell proteins carried large-sized oligosaccharides as evidenced by repeated pronase treatments, hydrazinolysis, and β-elimination experiments. The oligosaccharides consisted of mannose, fucose, galactose, and N-acetylglucosamine.The PA 1 cells contained also oligomannosyl type glycans, presumably linked to asparagine (fraction C glycopeptides). These glycopeptides were strongly bound to Con A – Sepharose and their oligosaccharides were released by endo-β-N-acetylglucosaminidase H. The liberated glycans ranged from Man5GlcNAc to Man9GlcNAc as analyzed by paper chromatography."Pulse–chase" experiments suggest that there is a precursor–product relationship between the mannose label in the fraction C (oligomannosyl type) glycopeptides and the fraction A glycopeptides.