The carbohydrate chains of the β subunit of human chorionic gonadotropin produced by the choriocarcinoma cell line BeWo.

The N-linked carbohydrate chains of the β subunit of human chorionic gonadotropin (hCG-β) isolated from the culture fluid of the choriocarcinoma cell line BeWo were released enzymatically by peptide-N&sup4;-(N-acetyl-β-glucosaminyl)asparagine amidase F. Subsequently, the O-linked oligosaccharides were split off from the N-deglycosylated protein by mild alkaline borohydride treatment. The carbohydrate chains were purified in their intact sialylated forms by FPLC anion-exchange chromatography on Mono Q, HPLC on Lichrosorb-NH2, and high-pH anion-exchange chromatography on CarboPac PA1. ¹H-NMR spectroscopic analysis of the major fractions demonstrates the occurrence of the following sialylated diantennary and triantennary N-linked oligosaccharides. Residues not written in bold letters are variably present. [ABSTRACT FROM AUTHOR]