Oligosaccharides obtained from a blood-group-Sd(a+) Tamm-Horsfall glycoprotein. An n.m.r. study

Abstract

Treatment of Tamm-Horsfall urinary glycoprotein with Bacteroides fragilis endo-,J-galactosidase over a range of enzyme concentrations, pH and temperature resulted in the release of a small but constant proportion of the terminal sugars, which indicates the presence in the glycoprotein of relatively few enzyme-susceptible -GIcNAc8l-3Gal,/l-4GlcNAc-units. Three oligosaccharides were isolated from the enzyme digest and characterized as Galfl6-4GlcNAcfll-3Gal (I), NeuAcz2-3Gal/J1-4 GlcNAcf6l-3Gal (II) and GalNAcfll-4(NeuAca2-3)Gal/J1-4GlcNAc,81-3Gal (III) by methylation analysis and exo-glycosidase digestion. The alditols of these oligosaccharides and related structures were examined by 500 MHz 'H-n.m.r. spectroscopy aided by spin-spin decoupling and two-dimensional correlated spectroscopy. An almost complete assignment of proton shifts was possible, and significant differences between the signals of some of the protons in the blood-group-Sda-active oligosaccharide III and literature values for the corresponding signals in the structurally related Cad-blood-group determinant are noted. INTRODUCTIONThe Sda-blood-group determinant is carried on the erythrocytes of about 92% of individuals and is the sole

The Asn‐linked carbohydrate chains of human Tamm‐Horsfall glycoprotein of one male

“…Previously, a Sd"-active pentasaccharide, released from T-H glycoprotein by endo-fl-galaclosidase. has been charactcrized (Donald et al, 1983;Donald and Feeney, 1986). Furthermore, studies on glycopeptide mixtures indicated that the Sd" determinant is present in triantennary and tetraantcnnary compounds (Williams et al, 1984).…”

“…1979;Soh et al, 1980;Afonso et al, 1981;Donald et al, 1982Donald et al, , 1983Williams et al, 1984;Serafini-Cessi et al, 1984a, b;Donald and Feeney, 1986;Dall'Olio et al, 1988;Smagula et al, 1990). Tn the present study the N-linked carbohydrates were enzymically released from T-H glycoprotein of one male donor by PNGase-F, and fractionated into more than 150 fractions by a combination of three liquidchromatographic techniques.…”

“…The structural element NeuSAca2 -3(GalNAc/Y1-4)GaI/31-4GlcNAcfiI -is rccogni7ed from Lhc typical signals for NeuSAc H-3a at 6 = 1.927 and H-3e at 6 = 2.662, in conjunction with those for GalNAc H-1 at 6 = 4.758 (42"C), GalNAc NAc methyl at 6 = 2.015, as well as Gal H-3 at 6 = 4.151 (cf. Blanchard et al, 1983; Williams et a]., 1984; Donald and Feeney, 1986;Nasir-UdDin et al. 1986: Soh ct al., 1989.…”

“…It has been shown that the Sd" blood-group determinant, present in over 90% of Caucasian erythrocytes, is also associated with the carbohydrate part of T-H glycoprotein (Soh et al, 1980;Donald ct al., 1982), and involves a terminal Neu5Acx2-3(GalNAcPI -4)GalPl-4GlcNAcp1-element (Donald ct al., 1983). Furthermore, the structure has been determined of a Sd" active pentasaccharide cleaved from T-H glycoprotein with endo-P-galactosidase (Donald et al, 1983;Donald and Feeney, 1986). Previous studies on T-H-glycopeptide mixtures have revealed that the Sd" determinant resides in the nonreducing termini of branched N-glycans (Williams et al, 1984).…”

Sulfated di‐, tri‐ and tetraantennary N‐glycans in human Tamm‐Horsfall glycoprotein

“…Furthermore, GalNAc H1 is observed at δ 4.73Ϫ4.76 (42°C), while its NAc signal resonates at δ 2.015Ϫ2.019. Due to the attachment of GalNAc to Gal via a (β1-4) linkage, Gal H4 resonates at δ 4.11Ϫ4.12 and H3 at δ 4.15 (Williams et al, 1984;Donald and Feeney, 1986;Hård et al, 1992).…”