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At least 19 recordsLinked to original sources
PubMed1986

Carbohydrate sequences detected by murine monoclonal antibodies.

The carbohydrate sequences of cell surface glycolipids change during differentiation and oncogenic transformation. To detect these structural changes, murine monoclonal antibodies have been produced in many different laboratories. Some of these antibodies are used to distinguish various cell types such as normal and transformed cells, while others are used to analyze developmentally regulated antigens. Recently, the structures of many of these carbohydrate antigens have been determined. The availability of these well-defined monoclonal antibodies will be useful for the study of the regulation and function of glycoconjugates.

Animals↗
PubMed1984

Novel oligosaccharide chains on polysialoglycoproteins isolated from rainbow trout eggs. A unique carbohydrate sequence with a sialidase-resistant sialyl group, DGa1NAc beta 1 leads to 4(NeuGc2 leads to 3)DGa1NAc.

A series of novel carbohydrate chains all possessing a hitherto unknown trisaccharide unit, Ga1NAc beta 1 leads to 4-(NeuGc2 leads to 3)Ga1NAc beta 1 leads to, have been isolated from trout egg polysialoglycoproteins, a new class of glycoproteins, on alkali-borohydride treatment. On the basis of chemical (methylation, Smith degradation, and hydrazinolysis-nitrous deamination) and direct-probe mass spectrometric methods. deamination) and direct-probe mass spectrometric methods, the structures of a series of the first major type of oligosaccharide alditols having a sialidase-resistant N-glycolyneuraminic acid residue in each molecule were determined. The structures thus determined are novel and all possess a unique carbohydrate sequence (sialidase-resistant unsubstituted sialyl group italicized): Ga1NAc beta 1 leads to 4(NeuGc2 leads to 3)Ga1NAc beta 1 leads to 3Gal beta 1 leads to-4Gal beta 1 leads to 3[(leads to 8NeuGc alpha 2)n leads to 6]Ga1NAcol (n = 0 through 3).

Animals↗
PubMed1980

Expression of blood group I and i active carbohydrate sequences on cultured human and animal cell lines assessed by radioimmunoassays with monoclonal cold agglutinins.

Human monoclonal anti-I and anti-i antibodies, reactive with known carbohydrate sequences, have been used as reagents to quantitate (by radioimmunoassay) and visualize (by immunofluorescence) the expression of the various blood group I and i antigenic determinants in a variety of cultured cell lines commonly used in laboratory investigations. It has been shown that the antigens they recognize are widely distributed on the surface of human and animal cell lines, expressed in varying amounts in different cell lines and on individual cells within a given cell line. In two cell lines, a transformation-associated increase in the expression of I antigen was observed. Because of their precise specificity for defined carbohydrate chain domains, these autoantibodies have become valuable reagents in biological chemistry.

Agglutinins↗
PubMed1984

The incorporation of glycolipids with defined carbohydrate sequence into liposomes and the effects on partition in aqueous two-phase systems.

A glycolipid with a defined carbohydrate sequence, derived from the glycoprotein fetuin, has been synthesised and incorporated into liposomes. The effect of the glycolipid on partition of the liposomes in aqueous two-phase systems has been investigated. Incorporation of glycolipid into liposomes changed their partition behaviour in a concentration-dependent manner. The effects on partition of the sequential removal of the terminal carbohydrates were investigated. Partition behaviour appeared to be determined by the net effect of a range of factors including the nature of the terminal carbohydrate, interactions of the lipid region of the glycolipid and possibly carbohydrate chain length. The electrostatic potential difference which can be created between the phases (by the inclusion of certain ions, notably phosphate) appeared to have no detectable effect on partition, even when N-acetylneuraminic acid was present as the terminal carbohydrate of the glycolipid.

Glycolipids↗
PubMed1990

Expression and distribution of carbohydrate sequences in chick germ cells: a comparative study with lectins and the NC-1/HNK-1 monoclonal antibody.

The expression of end-chain sugar residues and of oligosaccharidic sequences has been investigated in chick germ cells at critical stages during the migration, proliferation and sexual differentiation of these cells. Fluorescent lectins and indirect immunofluorescence studies using the NC-1/HNK-1 monoclonal antibody indicate a remarkable control of glycosylation during germ cell embryonal life. Besides a retained expression of glucose/mannose residues, it was found that alpha- and beta-galactose residues, N-acetyllactosamine and N-N' diacetylchitobiose sequences as well as the sulfated trisaccharidic NC-1 epitope were detectable in a stage-specific pattern. Present at a very high density in the cytoplasm and on the surface of the early germ cells at premigrative and migratory stages, the staining for these carbohydrate sequences gradually disappeared when the germ cells settled and proliferated in the developing gonadal primordia. The disaccharide Gal beta 1----3 Gal NAc was exclusively detected in migrating PGCs. In sexualized gonads, acetyllactosamine and/or diacetylchitobiose were similarly reexpressed in both oogonia and spermatogonia. Spermatogonia displayed beta-galactose residues and a high immunoreactivity with the NC1 Mab, indicating modulations in PGC glycosylations related to the acquisition of sexual phenotypes. In addition NC-1 was found to be expressed in the somatic component of the undifferentiated gonad and in the testis interstitial gland.

Animals↗
PubMed1992

cDNA, amino acid and carbohydrate sequence of barley seed-specific peroxidase BP 1.

The major peroxidase of barley seed BP 1 was characterized. Previous studies showed a low carbohydrate content, low specific activity and tissue-specific expression, and suggested that this basic peroxidase could be particularly useful in the elucidation of the structure-function relationship and in the study of the biological roles of plant peroxidases (S.K. Rasmussen, K.G. Welinder and J. Hejgaard (1991) Plant Mol Biol 16: 317-327). A cDNA library was prepared from mRNA isolated from seeds 15 days after flowering. Full-length clones were obtained and showed 3' end length variants, a G+C content of 69% in the translated region, a 90% G or C preference in the wobble position of the codons and a typical signal peptide sequence. N-terminal amino acid sequencing and sequence analysis of tryptic peptides verified 98% of the sequence of the mature BP 1 which contains 309 amino acid residues. BP 1 is the first characterized plant peroxidase which is not blocked by pyroglutamate. BP 1 polymorphism was observed. BP 1 is less than 50% identical to other plant peroxidases which, taken together with its developmentally dependent expression in the endosperm 15-20 days after flowering, suggests a unique biological role of this enzyme. The barley peroxidase is processed at the C-terminus and might be targeted to the vacuole. The single site of glycosylation is located near the C-terminus in the N-glycosylation sequon -Asn-Cys-Ser- in which Cys forms part of a disulphide bridge. The major glycan is a typical plant modified-type structure, Man alpha 1-6(Xyl beta 1-2)Man beta 1-4GlcNAc beta 1-4(Fuc alpha 1-3)GlcNAc. The BP 1 gene was RFLP-mapped on barley chromosome 3, and we propose Prx5 as the name for this new peroxidase locus.

Amino Acid Sequence↗
PubMed1984

Variation in the core and branch carbohydrate sequences of serum glycoprotein hormone alpha subunit as determined by lectin affinity chromatography.

Serum alpha subunits from patients with pituitary tumours and from normal controls were studied for their ability to bind to Lens culinaris agglutinin-Sepharose (LCA), L-phytohaemagglutinin-agarose (L-PHA) and soybean agglutinin-Sepharose (SBA). Serum alpha subunits from normal controls which had previously been shown to bind to Concanavalin A-Sepharose (Con A) were not retained by LCA. In contrast, Con A-reactive alpha subunits from patients with pituitary tumours bound specifically to LCA. Non-Con A-reactive alpha subunits from patients with pituitary tumours were also largely not bound to LCA, but were retained by L-PHA. No alpha subunits from any source bound to SBA. These results indicate that the structural alterations resulting in non-Con A-reactive serum alpha subunits include highly branched complex oligosaccharides in addition to the hybrid-type glycans previously described. The increased branching appears to be associated with fucosylation in the core region of the oligosaccharides. Serum alpha subunit from any source appears to be devoid of terminal N-acetylgalactosamine residues. These structural modifications may be related to the variable biological activity of alpha subunit which has been reported.

Carbohydrate Sequence↗
PubMed1988

Lipooligosaccharides (LOS) of Neisseria gonorrhoeae and Neisseria meningitidis have components that are immunochemically similar to precursors of human blood group antigens. Carbohydrate sequence specificity of the mouse monoclonal antibodies that recognize crossreacting antigens on LOS and human erythrocytes.

We have used mouse mAbs, 3F11 and 06B4, that are specific for highly conserved epitopes of Neisseria gonorrhoeae lipooligosaccharides (LOS) to identify immunochemically similar structures on human erythrocytes. mAb 3F11 agglutinated erythrocytes from all randomly selected adult humans, while mAb 06B4 agglutinated only 80% of the same specimens. The antibodies had an activity with erythrocytes similar to human cold agglutinins in that agglutination occurred at 4 degrees C and decreased with increasing incubation temperature. Human infant erythrocytes were agglutinated less well, but enzymatic treatment of either infant or adult cells resulted in an increase in expression of the 3F11- and 06B4-defined epitopes. Both antibodies bound to a series of neutral glycosphingolipids from human erythrocytes and neutrophils that have a type 2 (Gal beta 1----4GlcNAc) or N-acetyllactosamine structure. Neither antibody bound to glycosphingolipids from human meconium, which have a type 1 (Gal beta 1----3GlcNAc) structure. The antibodies were unable to bind to N-acetyl-lactosamine glycosphingolipids with a nonreducing terminal sialic acid or a Gala1----3Gal disaccharide. Antibody binding also was blocked by the presence of fucose linked to the penultimate glucosamine residue of N-acetyllactosamine glycosphingolipids. Although both antibodies bound to linear and branched-chain N-acetyllactosamine glycosphingolipids, 3F11 had a higher affinity for branched structures than did 06B4. The activity of 3F11 with human adult and infant treated and untreated erythrocytes with N-acetyllactosamine glycosphingolipids, and with LOS was very similar, if not identical, in specificity to 1B2, an mAb prepared from mice inoculated with a linear N-acetyllactosamine glycosphingolipid.

Adult↗
PubMed1988

Many pulmonary pathogenic bacteria bind specifically to the carbohydrate sequence GalNAc beta 1-4Gal found in some glycolipids.

Pneumonia is one of the most common causes of death from infectious disease in the United States. To examine the possible role of carbohydrates as adhesion receptors for infection, several pulmonary pathogenic bacteria were studied for binding to glycosphingolipids. Radiolabeled bacteria were layered on thin-layer chromatograms of separated glycosphingolipids, and bound bacteria were detected by autoradiography. The classic triad of infectious bacteria found in cystic fibrosis, Pseudomonas aeruginosa, Haemophilus influenzae, and Staphylococcus aureus, along with other bacteria commonly implicated in typical pneumonia, such as Streptococcus pneumoniae, Klebsiella pneumoniae, and certain Escherichia coli, bind specifically to fucosylasialo-GM1 (Fuc alpha 1-2Gal beta 1-3GalNAc beta 1-4Gal beta 1-4Cer), asialo-GM1 (Gal beta 1-3GalNAc beta 1-4Gal beta-1-4Galc beta 1-1Cer), and asialo-GM2 (GalNAc beta 1-4Gal beta 1-4Glc beta 1-1Cer). Bacteria maintained in nutrient medium bind better than the same cells suspended in buffer. They do not bind to galactosylceramide, glucosylceramide, lactosylceramide, trihexosylceramide, globoside, paragloboside, Forssman glycosphingolipid, or several other glycosphingolipids tested, including the gangliosides GM1, GM2, GM3, GD1a, GD1b, GT1b, and Cad. The finding that these pathogens do not bind to lactosylceramide suggests that beta 1-4-linked GalNAc, which is positioned internally in fucosylasialo-GM1 and asialo-GM1 and terminally in asialo-GM2, is required for binding. beta-N-Acetylgalactosamine itself, however, is not sufficient for binding, as the bacteria did not bind to globoside, which contains the terminal sequence GalNAc beta 1-3Gal. These data suggest that these bacteria require at least terminal or internal GalNAc beta 1-4Gal sequences unsubstituted with sialyl residues for binding. Other bacteria, including Mycoplasma pneumoniae, Streptococcus pyogenes, Salmonella species, and some E. coli, do not bind to the GalNAc beta 1-4Gal sequence. The biological relevance of these data is suggested by our finding that substantial amounts of asialo-GM1 occur in human lung tissue.

Animals↗
PubMed1991

Distribution of (fucogalactosyl-)epitope expressing glycoconjugates in rat brain.

Glycoconjugates are known to be concentrated in plasma membranes, especially in synaptic junctions, where they subserve various functions in neural connectivity. Here we report the cellular distribution of a new monoclonal antibody recognizing (fucogalactosyl) sequences in carbohydrate structures. The most pronounced immunoreactivity was found in fibrous astrocytes, in many parts of the brain and with lower density in various neuronal elements. This points to the expression of identical carbohydrate sequences on molecules within certain glial and neuronal elements. Previous intracerebral injections of the antibody interfered with long term memory formation. Therefore, functions mediated by corresponding glycoproteins in neurons and glia cells or even neuron-glial interactions, might be relevant for information-processing.

Animals↗
PubMed1995

Structure determination of the octa- and decasaccharide sequences isolated from the carbohydrate-protein linkage region of porcine intestinal heparin.

Previously we isolated a tetrasaccharide-serine and a hexasaccharide-serine from the carbohydrate-protein linkage region of porcine intestinal heparin after digestion with a mixture of Flavobacterium heparinase and heparitinases I and II (Sugahara, K., Yamada, S., Yoshida, K., de Waard, P., and Vliegenthart, J.F.G. (1992) J. Biol. Chem. 267, 1528-1533). In this study four longer carbohydrate sequences (I-IV) attached to Ser or a dipeptide (Ser-Gly or Gly-Ser), which accounted for at least 18.2% of the total linkage region, were isolated from the same heparin preparation after digestion with heparinase only. IV was successfully isolated only after subsequent digestion with glycuronate-2-sulfatase. Their structures were determined by chemical and enzymatic analyses and 1H NMR spectroscopy and found to be the following octa- and decasaccharide sequences attached to Ser in a molar ratio of 1.1:2.3:1.0:1.3: delta HexA(2S)alpha 1-4GlcN(NS,6S)alpha 1-4GlcA beta 1-4GlcNAc alpha 1-4- GlcA beta 1-3Gal beta 1-3Gal beta 1-4Xyl beta 1-O-Ser (I), delta HexA(2S)alpha 1- 4GlcN(NS,6S)alpha 1-4IdoA alpha 1-4GlcNAc alpha 1-4GlcA beta 1- 3Gal beta 1-3Gal beta 1-4Xyl beta 1-O-Ser (II), delta HexA(2S)alpha 1- 4GlcN(NS,6S)alpha 1- 4IdoA alpha 1-4GlcNAc alpha 1-4GlcA beta 1-4GlcNAc-alpha 1- 4GlcA beta 1-3Gal beta 1-3Gal beta 1-4Xyl beta 1-O-Ser (III), delta HexA alpha 1-4GlcN(NS,6S)alpha 1-4IdoA alpha 1-4GlcNAc(6S)alpha 1- 4GlcA beta 1-3Gal beta 1-3Gal beta 1-4Xyl beta 1-O-Ser (IV) (delta HexA, GlcA, IdoA, and GlcN represent 4,5-unsaturated hexuronic acid, D-glucuronic acid, L-iduronic acid, and D-glucosamine, whereas 2S, 6S, and NS stand for 2-sulfate, 6-sulfate, and N-sulfate, respectively). I and II contained 1 mol of Gly in addition to Ser. The four structures indicate that sulfation in heparin chains takes place on the monosaccharide residues located in closer vicinity to the core protein than found for heparan sulfate chains and that there exist at least several heparin subclass chains with different linkage region structures. The significance of the isolated structures is discussed in relation to the biological functions and the biosynthetic mechanisms of heparin.

Amino Acids↗
PubMed1983

Oligosaccharide units of lysosomal cathepsin D from porcine spleen. Amino acid sequence and carbohydrate structure of the glycopeptides.

The amino acid sequences near the glycosylation sites and the oligosaccharide structures have been determined for the lysosomal protease cathepsin D from porcine spleen. Cathepsin D light and heavy chains were separately digested with proteases and the glycopeptides were purified. A single sequence was constructed from the amino acid sequence of the light chain glycopeptides which is: Tyr-Asn-Ser-Gly-Lys-Ser-Ser-Thr-Tyr-Val-Lys-Asn(CH2O)-Gly-Thr-Thr-Phe. A single glycopeptide sequence was also obtained for the heavy chain: Lys-Gly-Ser-Leu-Asp-Tyr-His-Asn(CH2O)-Val-Thr-Arg-Lys-Ala-Tyr. The light chain sequence is homologous with the sequence of porcine pepsin from residues 56 to 71. The heavy chain sequence is homologous with the pepsin sequence from residues 176 to 189. Thus, the 2 oligosaccharide-linked asparagines in cathepsin D correspond to residues 67 and 183 in pepsin and other homologous aspartyl proteases. These positions are located on the surface of the crystal structures of aspartyl proteases. Five oligosaccharides linked to Asn-67 were separated and their structures determined with proton NMR. Four major oligosaccharides are structural variants from the high mannose-type having 3, 5, 6, and 7 mannoses, respectively. A minor structure contained a third GlcNAc. Three oligosaccharide structures were found linked to Asn-183. Two major oligosaccharides are of the high mannose-type each with 5 mannose residues. One of the two contains a fucose linked to a GlcNAc. A third, very minor oligosaccharide contains galactose.

Amino Acid Sequence↗
PubMed1987

The elderberry (Sambucus nigra L.) bark lectin recognizes the Neu5Ac(alpha 2-6)Gal/GalNAc sequence.

Carbohydrate binding properties of a new plant lectin isolated from elderberry (Sambucus nigra L.) (SNA) bark were studied using the techniques of quantitative precipitation, hapten inhibition, and equilibrium dialysis. Purified SNA precipitates highly sialylated glycoproteins such as fetuin, orosomucoid, and ovine submaxillary mucin, but not their asialo derivatives. Hapten inhibition experiments showed that both D-Gal and D-GalNAc are weak inhibitors of SNA-glycophorin precipitation, but neither New5Ac nor Neu5Gc is an inhibitor. A series of oligosaccharides which contain the terminal Neu5Ac(alpha 2-6)Gal sequence showed an extremely high inhibitory potency (1,600-10,000 times more inhibitory than Gal). On the other hand, oligosaccharides with the Neu5Ac(alpha 2-3)Gal linkage were only 30-80 times more inhibitory than Gal, thus showing a marked preference for the 2,6-linked isomer. Hapten inhibition with Gal and its epimers suggested that the equatorial OH at C-3 and the axial OH at C-4 of the D-pyranose ring are strict requirements for binding. Conversion of the Neu5Ac residue to its 7-carbon analogue by selective periodate oxidation of its glyceryl side chain, followed by NaBH4 reduction, completely destroyed the ability of fetuin and orosomucoid to precipitate with SNA. Moreover, the same treatment of Neu5Ac(alpha 2-3)lactitol also abolished its ability to inhibit the precipitation reaction, suggesting that the glyceryl side chain of NBu5Ac (especially the C-8 and/or C-9 portion) is an important determinant for SNA. The increased inhibitory potency of various glycosides with beta-linked nonpolar aglycons suggested the presence of a hydrophibic interacting region adjacent to the carbohydrate binding site. The results of equilibrium dialysis using [3H] Neu5Ac(alpha 2-6)lactitol as ligand showed the presence of two equivalent, noninteracting carbohydrate binding sites in this tetrameric glycoprotein lectin (Ka = 3.9 X 10(5) M-1).

Acetylgalactosamine↗
PubMed1988

Human urinary kallikrein--amino acid sequence and carbohydrate attachment sites.

The amino acid sequence of human urinary kallikrein was determined by protein-chemical methods. The peptide chain contains 238 amino acid residues. Ten half-cystine residues form five disulfide bridges. Six carbohydrate side chains could be identified, three of them are N-glycosidically linked to asparagine which is present in the acceptor sequon Asn-Xaa-Thr (or -Ser) and three are O-glycosidically linked to two serine residues and one threonine residue, respectively. Comparison of the primary structure of human urinary kallikrein with that of other serine proteinases especially porcine kallikrein and rat kallikrein shows a high degree of homology. IVGGWECEQHSQPWQAALYHFSTFQCGGILVHRQWVLTA AHCISDNYQLWLGRHNLFDDENTAQFVHVSESFPHPGFN MSLLENHTRQADEDYSHDLMLLRLTEPADTITDAVKVVE LPTQEPEVGSTCLASGWGSIEPENFSFPDDLQCVDLKIL PNDECEKAHVQKVTDFMLCVGHLEGGKDTCVGDSGGPLM CDGVLQGVTSWGYVPCGTPNKPSVAVRVLSYVKWIEDTIAENS.

Amino Acid Sequence↗