Structural analysis of oligosaccharides isolated from the urine of a blood group A, secretor, woman during pregnancy and lactation.

Abstract

Twenty different oligosaccharides have been isolated from urine collected from an A, Le(a- b+), secretor woman during her pregnancy and subsequent lactation. Nine of these have been found previously in the milk of Le (a- b+) individuals. Three new fucose-containing oligosaccharides denoted lacto-N-neotrifucoheptaose II (alpha-L-Fuc-(1 leads to 2)-beta-D-Gal-(1 leads to 4)-[alpha-L-Fuc-(1 leads to 3)]-beta-D-GlcNAc-(1 leads to 3)-[alpha-L-Fuc-(1 leads to 2)]-beta-D-Gal-(1 leads to 4)-D-Glc), lacto-N-neodfucohexaose I (alpha-L-Fuc-(1 leads to 2)-beta-D-Gal-(1 leads to 4)-[alpha-L-Fuc-(1 leads to 3)]beta-D-GlcNAc-(1 leads to 3)-beta-D-Gal-(1 leads to 4)-D-Glc), and lacto-N-difucohexaose IV (alpha-L-Fuc-(1 leads to 2)-beta-D-Gal-(1 leads to 3)-beta-D-GlcNAc-(1 leads to 3)-[alpha-L-Fuc-(1 leads to 2)]-beta-D-Gal-(1 leads to 4)-D-Glc) are described. Three new myo-inositol-containing oligosaccharides which are characteristic for pregnancy have also been isolated. Their structures are: alpha-D-GalNAc-(1 leads to 3)-[alpha-L-Fuc-(1 leads to 2)]-beta-D-Gal-(1 leads to 0)-[alpha-L-Fuc-(1 leads to 0)]-myo-inositol; alpha-L-Fuc-(1 leads to 2)-beta-D-Gal-(1 leads to 0)-[alpha-D-Fuc-(1 leads to 0)]myo-inositol; and alpha-L-Fuc-(1 leads to 2)-beta-D-Gal-(1 leads to 0)-myo-inositol, respectively. Three oligosaccharides containing only glucose were found and partially characterized. In addition, two oligosaccharides described previously (a glucose tetrasaccharide (Hallgren, P., Hansson, G., Henriksson, K.-G., Häger, A., Lundblad, A., and Svensson, S. (1974) Eur. j. clin. Invest. 4, 429-433) and a urine A pentasaccharide (Lundblad, A., and Svensson, S. (1973) Carbohyd. Res. 30, 187-189) were also isolated and characterized. The isolation procedure included ultrafiltration, gel chromatography on Sephadex G-25, and preparative paper chromatography, Structural determination involved sugar and methylation analyses. Tri- and tetrasaccharides were investigated by combined gas-liquid chromatography-mass spectrometry. Sequence analyses of larger oligosaccharides were performed by combined gas-liquid chromatography-mass spectrometry of di- and trisaccharides obtained after partial acid hydrolysis of the parent compound. Anomeric configurations were deduced from optical rotations and by comparison with authentic samples.