[Structure of carbohydrate chains of dimeric molecules and individual subunits of gonadotropin from the Russian sturgeon].

Carbohydrate chains of gonadotropin from the Russian sturgeon hypophysis, as well as of alpha- and beta-subunits of the hormone, were split off and fractionated by gel-chromatography and HPLC. More than ten oligosaccharides released from the male and female hormones gave almost identical patterns, whereas differences between alpha- and beta-subunits were more noticeable. Basing on the chromatographic properties and monosaccharide compositions of the oligosaccharides isolated and the known structures of N-linked carbohydrates of mammalian hormones, the common carbohydrate chain of sturgeon gonadotropin is as follows: [formula: see text] Some oligomannosidic and/or hybrid chains and small oligosaccharides of the pentasaccharide core type were also found. Carbohydrate chains of fish gonadotropin have fewer sialic acid residues and significantly fewer (if any) sulphate groups than the mammalian hormones.