title: A novel sialylfucopentaose in human milk. Presence of this oligosaccharide is not dependent on expression of the secretor or Lewis fucosyltransferases.
abstract: We have identified a novel oligosaccharide in human milk that is a fucosyl derivative of sialyltetrasaccharide c (NeuAc alpha 2-6Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc). This oligosaccharide was purified by affinity chromatography on a column of immobilized Ricinus communis I lectin. Structural analyses of radiolabeled oligosaccharides by exoglycosidase digestions, binding by specific anti-carbohydrate antibodies, and analysis of the 3H-labeled glucitol derivative obtained after permethylation and hydrolysis are consistent with the following proposed structure. (formula; see text) The analyses of human milk sialylpentasaccharides from donors typed as Le(a-,b+), Le(a+,b-), and Le(a-,b-) secretor confirmed the secretor gene-dependent expression of the sialylated lacto-N-fucopentaose I (Fuc alpha 1-2Gal beta 1-3[NeuAc alpha 2-6]GlcNAc beta 1-3Gal beta 1-4Glc) and the Lewis gene-dependent expression of the sialylated lacto-N-fucopentaose II (NeuAc alpha 2-3Gal beta 1-3[Fuc alpha 1-4]GlcNAc beta 1-4Glc). However, the presence of this novel oligosaccharide in human milk is not dependent on the expression of either the secretor gene or the Lewis gene-specified fucosyltransferases.
mesh_terms: D002240:Carbohydrate Sequence; D002846:Chromatography, Affinity; D005643:Fucose / Q000031:analogs & derivatives / Q000032:analysis; D005647:Fucosyltransferases / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000378:metabolism; D006602:Hexosyltransferases / Q000378:metabolism*; D006801:Humans; D008895:Milk, Human / Q000032:analysis*; D009844:Oligosaccharides / Q000032:analysis*; D012794:Sialic Acids / Q000032:analysis
chemical_list: D009844:Oligosaccharides; D012794:Sialic Acids; D005643:Fucose; D005647:Fucosyltransferases; D006602:Hexosyltransferases; C019818:3-galactosyl-N-acetylglucosaminide 4-alpha-L-fucosyltransferase; D006026:Glycoside Hydrolases