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J Finne

Publications and source records attributed to J Finne.

At least 91 records · Page 5Linked to original sources
PubMed1982

Blood group A and H determinants in polyglycosyl peptides of A1 and A2 erythrocytes.

Polyglycosyl peptides were isolated from delipidated erythrocyte membranes of human blood-group A1 and A2 erythrocytes by extensive pronase digestion and gel filtration. As estimated by the amounts of N-acetylgalactosamine and 2-O-substituted galactose residues about 85% of the possible acceptor sites (H determinants) were saturated with A determinants in A1 polyglycosyl peptides whereas only 25% of H sites were filled in A2 glycopeptides. The distribution of A and H determinants in the glycopeptides was studied by affinity chromatography with Sepharose-bound Bandeiraea simplicifolia I-lectin (binds blood-group A and B determinants) and Ulex Europeaus I-lectin (binds blood-group H determinants). About 55% of the polyglycosyl peptides contained A, H, or A and H determinants in both A1 and A2 blood subgroups. 48% of the polyglycosyl peptides of blood group A1 and 10% of A2 bound to Bs I-lectin. 25% of the polyglycosyl peptides in A1 and 53% in A2 carried H determinants. The molecular size, monosaccharide composition and the substitution pattern of the monosaccharides in the Bs-I-bound polyglycosyl peptides were very similar in both A1 and A2 blood groups. The only difference was the amount of N-acetylgalactosamine which was on the average 3.7 mol/mol in A1 and 2.5 mol/mol in A2. The active fraction was found to be heterogeneous with respect to the amount of A determinants, which varied from 1 to 6 per glycopeptide in A1 and A2 polyglycosyl peptides. The findings do not indicate a structural difference between blood-group A1 and A2 polyglycosyl peptides and state chemically that A1 glycopeptides contain more A determinants than A2 glycopeptides.

ABO Blood-Group System↗
PubMed1981

Blood-group A and B determinants are located in different polyglycosyl peptides isolated from human erythrocytes of blood-group AB.

The distribution of blood-group A and B determinants was studied by isolating blood-group ABH-active polyglycosyl peptides from delipidated human blood-group AB erythrocyte membranes after extensive digestion with pronase followed by chromatography on Bandeiraea simplicifolia I (BsI) lectin coupled to Sepharose. 20% of the polyglycosyl peptides were bound to BsI lectin. The glycopeptides bound were further fractionated using the blood-group-A-specific lectin from Vicia cracca (Vc). Approximately half of these were bound to the Vc lectin. The glycopeptides, which were bound to the Vc column, were not bound to the blood-group-B-specific isolectin from B. simplicifolia (BsIB4) whereas the Vc-unbound glycopeptides readily bound. The results indicate that in the polyglycosyl peptides isolated from AB erythrocytes A and B determinants are located in different carbohydrate chains. The polyglycosyl peptides, which did not bind to BsI lectin, were composed on the average of 30 monosaccharide units and those that bound contained on the average 55 monosaccharide units. The sugar composition was similar in both fractions except that N-acetylgalactosamine was found only in the BsI-bound glycopeptides. The substitution patterns of the monosaccharides were quite similar in both fractions except 2,3-O-linked galactose, which was enriched 7.5-fold in the BsI-bound glycopeptides and 3,6-O-linked galactose, which also enriched in the BsI-bound glycopeptides suggesting that these have a more branched structure than the BsI-unbound glycopeptides. Glycopeptides derived from bands 3 and 4.5 were prepared from A1B-blood-group erythrocyte membranes and fractionated as above. 25% of the glycopeptides were bound to BsI-lectin from both samples. 70% of the BsI-bound material from band 3 was bound to Vc lectin and 60% from band 4.5. The results indicate heterogeneity in the glycosylation of these bands.

ABO Blood-Group System↗
PubMed1980

Molecular nature of the blood-group ABH antigens of the human erythrocyte membrane.

The oligosaccharide structures specifying the blood-group ABH determinants occur in the human erythrocyte membrane in different classes of compounds. The majority occur in a novel class of complex carbohydrate chains called the polyglycosyl chains. They are bound by an alkali-stable bond to glycoproteins (band 3, band 4.5) and occur also in glycolipids. Conventional glycosphingolipids as well as alkali-labile carbohydrate chains of glycoproteins (in the PAS-bands) are also carriers of the blood-group determinants.

ABO Blood-Group System↗
PubMed1980

Carbohydrate changes in glycoproteins of a poorly metastasizing wheat germ agglutinin-resistant melanoma clone.

Glycoproteins of a metastasizing line of B16 mouse melanoma and a poorly metastasizing wheat germ agglutinin-resistant clone were compared. Cell surface proteins and glycoproteins were isotopically labeled by lactoperoxidase-catalyzed iodination and by NaB3H4 reduction after oxidation by periodate or galactose oxidase and subsequently analyzed by gel electrophoresis and autoradiography. Differences were observed in the relative mobilities of several major cell surface components. Binding of 125I-labeled lectins to total cellular proteins on polyacrylamide gels following electrophoresis showed that the major wheat germ agglutinin-binding components of F1 cells were altered in Wa-4 cells. Similar differences were not observed in concanavalin A-binding components. Total cellular glycopeptides were analyzed after separation into structurally distinct classes. The acidic "complex" N-glycosidic glycopeptides from the resistant cells were of lower molecular weight than those from the parent cells. No differences were observed among the mannose-rich N-glycosidic glycopeptides or the alkali-labile O-glycosidic oligosaccharides. Structural studies involving methylation analysis revealed that in the altered glycopeptides of the resistant cells the amount of neuraminic acid residues was decreased to one-half, concomitant with an increase in the amount of fucose. The lost sialic acid was bound to C-3 of galactose, whereas the increased fucose was found on C-3 of 4-substituted N-acetylglucosamine. A possible basis for the glycosylation change and its relation to the biological behavior are discussed.

Animals↗
PubMed1979

Novel mannitol-containing oligosaccharides obtained by mild alkaline borohydride treatment of a chondroitin sulfate proteoglycan from brain.

Mannitol-containing oligosaccharides have been isolated from a rat brain proteoglycan after mild alkaline borohydride treatment under conditions which prevent "peeling." Their structural properties were studied by gas-liquid chromatography-mass spectrometry of disaccharides as their trimethylsilylated and permethylated derivatives, methylation, analysis, specific degradations, and CrO3 oxidation. The following components were identified: Gal(beta 1 leads to 4) [Fuc(alpha 1 leads to 3)]GlcNAc(beta 1 leads to 3)Manol,GlcNAc(beta 1 leads to 3)Manol, and Manol. Evidence was also obtained for the occurrence of a sialylated oligosaccharide and another (possibly sulfated) acidic oligosaccharide, both having the sequence GlcNAc(beta 1 leads to 3)Manol at their proximal ends. These mannitol-containing oligosaccharides constitute a novel group of alkali-labile oligosaccharides in mammalian glycoconjugates. The origin of the oligosaccharides and the possible occurrence of a carbohydrate-peptide linkage involving mannose are discussed.

Animals↗
PubMed1979

Differences between the carbohydrate units of cell-surface glycoproteins of moust B- and T-lymphocytes.

Carbohydrate units of cell-surface glycoproteins of mouse B- and T-lymphocytes, labelled in their sialic acid residues by the periodate/NaB3H4 method and in their galactose residues by the galactose oxidase/NaB3H4 method after neuraminidase treatment, have been studied. Glycopeptides were prepared from the labelled cells by Pronase digestion and fractionated by concanavalin A affinity chromatography into two fractions (A and B). Alkali-labile oligosaccharides were isolated after mild NaOH/NaBH4 treatment by gel filtration. The alkali-labile oligosaccharides were further analysed by t.l.c. To study the relative proportion of neutral mannose-rich carbohydrate units (fraction C) in lymphocyte glycoproteins, glycopeptides were also prepared from unlabelled cells and subjected to concanavalin A affinity chromatography after N-[3H]acetylation of their peptide moiety. The major alkali-labile oligosaccharide component of both cell types was identified as galactosyl-(beta 1 leads to 3)-N-acetylgalactosaminitol. T-Lymphocytes were characterized by a high proportion of this oligosaccharide and a lower proportion of alkali-stable fraction A glycopeptides, whereas the opposite was observed for B-lymphocytes. The relative proportions of the concanavalin A-binding fractions B and C were similar in both cell types. The differences observed may correlate with the different surface properties of B- and T-lymphocytes.

Animals↗
PubMed1978

Disialosyl paragloboside. A novel ganglioside isolated from human kidney.

A ceramide hexasaccharide was purified from the gangliosides of human kidney. Its structure was studied by methylation analysis, neuraminidase treatment, weak acid hydrolysis and chromium trioxide oxidation. The structure is suggested to be a disialosyl derivative of paragloboside: formula: (see text) Data indicating the possible existence of a corresponding trisialosyl derivative are also presented.

Carbohydrates↗
PubMed1978

The poly(glycosyl) chains of glycoproteins. Characterisation of a novel type of glycoprotein saccharides from human erythrocyte membrane.

Glycopeptides with complex carbohydrate structure were isolated from delipidated human erythrocyte membranes after digestion with pronase. The poly(glycosyl)peptides isolated (apparent molecular weight 4000--13000) are suggested to contain 20--70 sugar residues in an alkali-stable saccharide chain linked through N-acetylglucosamine to asparagine. The main sugar components are galactose and N-acetylglucosamine, which together account for 80% of total sugars. That the compounds isolated are glycopeptides and not glycolipids is concluded from the following findings: only trace amounts of glucose and fatty acids were present, and no long-chain (sphingosine) bases could be detected; on the other hand, the amounts of mannose and amino acids found are compatible with an N-glycosidic poly(glycosyl)peptide structure. The structure of the poly(glycosyl)peptides was studied using methylation analysis, exoglycosidase treatments, acid hydrolysis of the native as well as the N-deacetylated glycopeptides, and chromium trioxide oxidation. The studies indicate that the poly(glycosyl)peptides contain a repeating-3)galactosyl(beta1-4)N-acetylglucosaminyl(beta1-structure with branch points at the C-6 of the galactose residues. The saccharide chains are terminated in N-acetylglucosaminyl, galactosyl, N-acetylneuraminyl(alpha2-3 and 6)galactosyl and fucosyl(alpha1-2)galactosyl residues, and they also contain blood group A and B determinants.

Amino Acids↗