The carbohydrate structure of a glycopeptide released by the action of plasma kallikrein on bovine plasma high-molecular-weight kininogen.
Fragment 1, released from bovine plasma high-molecular-weight kininogen by the action of plasma kallikrein, is a glycopeptide with approximately 3 mol of each of N-acetylgalactosamine, galactose and sialic acid in one molecule. All these sugars were in the T-1 fragment obtained by tryptic digestion of fragment 1. Sialic acid can be completely released from the T-1 fragment by sialidase digestion. When this sialic acid-free T-1 fragment was incubated with purified diplococcal endo-alpha-N-acetylgalactosaminidase, all remaining sugars were released as a disaccharide. By Smith degradation and beta-galactosidase digestion, the structure of this disaccharide was found to be Gal beta 1 leads to 3GalNAc. Methylation analysis of the trisaccharide released from fragment T-1 by alkaline borohydride treatment indicated that all the galactose was obtained as the 2,4,6-tri-O-methyl derivative. Based on this evidence, the complete structure of the carbohydrate moieties of fragment 1 was proposed as Sialyl alpha 2 leads to 3Gal beta 1 leads to 3GalNAc. In addition, small amounts of a tetrasaccharide, Sialyl alpha 2 leads to 3Gal beta 1 leads to 3(Sialyl alpha 2 leads to 6)GalNAc also occurred as a carbohydrate chain of fragment 1.
D000818:Animals; D002241:Carbohydrates / Q000032:analysis; D002417:Cattle; D002849:Chromatography, Gas; D002854:Chromatography, Paper; D006020:Glycopeptides / Q000097:blood; D007610:Kallikreins / Q000097:blood; D007704:Kininogens / Q000097:blood; D013058:Mass Spectrometry; D008968:Molecular Conformation; D012794:Sialic Acids / Q000032:analysis
D002241:Carbohydrates; D006020:Glycopeptides; D007704:Kininogens; D012794:Sialic Acids; D007610:Kallikreins