Showing papers in "Glycoconjugate Journal in 1988"
TL;DR: A systematic nomenclature has been developed primarily for FAB-MS, but can be used as well for other ionization techniques and is applicable to spectra recorded in either the positive or negative ion mode during both MS and MS/MS experiments.
Abstract: A summary of the ion types observed in the Fast Atom Bombardment Mass Spectrometry (FAB-MS) and collision induced decomposition (CID) MS/MS spectra of glycoconjugates (glycosphingolipids, glycopeptides, glycosides and carbohydrates) is presented. The variety of product ion types that arise by cleavages within the carbohydrate moieties has prompted us to introduce a systematic nomenclature to designate these ions. The proposed nomenclature has been developed primarily for FAB-MS, but can be used as well for other ionization techniques [field desorption (FD), direct chemical ionization (DCI), laser desorption/Fourier transform (LD/FT), etc.], and is applicable to spectra recorded in either the positive or negative ion mode during both MS and MS/MS experiments. Ai, Bi and Ci labels are used to designate fragments containing a terminal (nonreducing end) sugar unit, whereas Xj, Yj and Zj represent ions still containing the aglycone (or the reducing sugar unit). Subscripts indicate the position relative to the termini analogous to the system used in peptides, and superscripts indicate cleavages within carbohydrate rings. FAB-MS/MS spectra of a native glycosphingolipid and glycopeptide, and a permethylated ganglioside are shown as illustrations.
2,497 citations
TL;DR: A general method is described for the assay of glycosyltransferase activity, which makes use of synthetic glycoside acceptors attached to hydrophobic aglycones, which can be rapidly separated from interfering radioactivity by adsorption on to reverse-phase C-18 cartridges.
Abstract: A general method is described for the assay of glycosyltransferase activity, which makes use of synthetic glycoside acceptors attached to hydrophobic aglycones. The products formed by incubation of an enzyme with acceptor and radiolabelled sugarnucleotide can then be rapidly (one minute) separated from interfering radioactivity by adsorption on to reverse-phase C-18 cartridges. After aqueous washing, products are easily isolated by elution with methanol. The utility of the method for the assay of β(1–4)galactosyltransferase, α(1–2)fucosyltransferase andN-acetylglucosaminyltransferase I and V is demonstrated.
278 citations
TL;DR: Xylose-containing glycans appear to increase the immunogenicity of the proteins to which they are attached, and it is suggested that they may be responsible for some allergic responses of people that are repeatedly exposed to plant or insect proteins.
Abstract: An antiserum raised against β-fructosidase isolated from the cell walls of suspension-cultured carrot cells cross-reacts with many plant proteins and hemocyanin ofHelix pomatia. The shared epitope appears to be a small complex glycan with a β(1–2)-linked xylose residue attached to the β-linked mannose residue of the core of an asparagine-linked oligosaccharide. There is strong cross-reactivity with the proteins of many seed plants, molluscs and insects, and no cross-reactivity with the proteins of fungi, algae, mosses, ferns, or any of the vertebrates tested. Xylose-containing glycans appear to increase the immunogenicity of the proteins to which they are attached, and we suggest that they may be responsible for some allergic responses of people that are repeatedly exposed to plant or insect proteins.
111 citations
TL;DR: After fractionation on Bio-Gel P-2 and purification on Mono-Q, the neutral oligosaccharide was investigated by 500-MHz1H-NMR spectroscopy and the primary structure of theN-linked carbohydrate chain was established to be:
Abstract: Ascorbic acid oxidase (E.C.1.10.3.3) from the green zucchini squash (Cucurbita pepo medullosa) is a copper-containing glycoprotein which catalyzes the reaction:l-ascorbic acid +1/2 O2→l-dehydroascorbic acid + H2O. The carbohydrate content of the purified plant glycoprotein amounted to 3% (w/w), and monosaccharide analysis revealed the carbohydrate moiety to be of theN-glycosidic type. The carbohydrate chains were released from the apoenzyme by digestion with PNGase-F immobilized on Sepharose 4B. After fractionation on Bio-Gel P-2 and purification on Mono-Q, the neutral oligosaccharide was investigated by 500-MHz1H-NMR spectroscopy. The primary structure of theN-linked carbohydrate chain was established to be:
53 citations
TL;DR: In this article, a 2C-conformation with more than 90%/3-anomeric configuration was established for the N-acetylated derivatives of neuraminic acid, including 5-acetamido-3,5-dideoxy-D-glycero-d-galactononulosonic acid.
Abstract: "Sialic acid" comprises all natural or synthetic derivatives of 5-amino-3~5-dideoxy-D-glycero-D-galacto-nonulosonic acid (Fig. 1), called neuraminic acid. This D-sugar is unstable in this form, due to a reaction between the 0 2 keto function and the 05 amino group. Thus, only N-acetylated derivatives occur in Nature, the most common being the N-acetylated compound 5-acetamido-3,5-dideoxy-D-glycero-D-galactononulosonic acid. In solution, this monosaccharide adopts a 2Cs-conformation with more than 90%/3-anomeric configuration as established by 1H-NMR experiments ([11, Fig. 2). As all other derivatives of neuraminic acid have the same conformation, free sialic acids are generally/3-anomers. Glycosidically-linked sialic acids, however, have the s-configuration, except the CMP-glycoside which is a/3-anomer [21. As this anomeric configuration is strictly followed, for simplicity ~ or/3 need not be added to abbreviations, except for synthetic derivatives with a different configuration.
42 citations
TL;DR: The suitability of p-aminobenzoic acid ethyl ester as an ultraviolet-absorbing reagent for the analysis of asparagine-linked oligosaccharides derived from glycoproteins was expanded and the elution profile and the proportion of oligosACcharides were in agreement with literature values.
Abstract: We have expanded on the suitability ofp-aminobenzoic acid ethyl ester as an ultraviolet-absorbing reagent [Wanget al., (1984) Anal Biochem 141:366–81] for the analysis of asparagine-linked oligosaccharides derived from glycoproteins. The oligosaccharides released from glycoproteins by hydrazinolysis/N-reacetylation were derivatized withp-aminobenzoic acid ethyl ester and the derivatives were purified and separated into neutral and acidic oligosaccharides on a PRE-SEP C18 cartridge. The acidic oligosaccharides could be further separated into a few species by high-voltage paper electrophoresis.
41 citations
TL;DR: In this article, the synthesis of artificial carbohydrate antigens derived from allyl 2-acetamido-2-deoxy-α, and β-d-glucopyranosides and acrylamide is described.
Abstract: The synthesis of artificial carbohydrate antigens derived from allyl 2-acetamido-2-deoxy-α-and β-d-glucopyranosides and acrylamide is described. The two anomeric glycosyl copolymers were prepared with and without spacer arms and their binding properties to lectins and antibodies are compared.
36 citations
TL;DR: The aim of this article is to summarize studies carriedout on the structure of non-human glycophorins, although some data concerning human glycophOrins are included for comparative purposes.
Abstract: Glycophorins are red cell membrane sialoglycoproteins, which contain multipleO-linked oligosacchride chains and carry most of the cell surface sialic acid. Due to this high content of sialic acid the glycophorins are strongly stained with periodic acid-Schiff (PAS) reagent after sodium sodicylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The term “glycophorin” was proposed initially for human red cell sialoglycoproteins [1,2] and now it is also used for sialoglycoproteins in animal red cell membranes. Furthermore, similar glycoproteins of non-erythrocyte origin have also been identified and given the same name [3], although the terms “leukosialin” and “sialophorin” were proposed for a major sialoglycoproteins of human leukocytes [4,5]. In this article the term “glycophorin” will be used only for sialoglycoproteins existing in the erythrocyte membrane. Glycophorins of human erythrocytes, carrying blood group MN, Ss and other determinants, have been thoroughly studied and their properties described in several review articles [3,6,7,8]. The aim of this article is to summarize studies carriedout on the structure of non-human glycophorins, although some data concerning human glycophorins are included for comparative purposes.
35 citations
TL;DR: Bovine submandibular glands were homogenized and fractionated under conditions which yielded subcellular fragments from mainly one cell type, the mucous acinar cell, as judged by morphological analysis of the glands before and after homogenization.
Abstract: Bovine submandibular glands were homogenized and fractionated under conditions which yielded subcellular fragments from mainly one cell type, the mucous acinar cell, as judged by morphological analysis of the glands before and after homogenization. The majorN-acetylneuraminate-9(7)-O-acetyltransferase activity was detected in the cytosolic fraction, a result supported by the high specific radioactivity of free sialic acids isolated after [14C]acetate-labelling experiments. Separation of membranes on a Ficoll density gradient gave six fractions which were analyzed biochemically and morphologically. The particulate activities of acetyltransferase and sialyltransferase were found in fractions containing smooth and mitochondrial membranes. MembraneO-acetyl sialic acids were present at the highest levels in these fractions and also had the highest specific radioactivity after [14C]acetate-labelling experiments. Significant amounts of theO-acetyltransferase activity also occur in the cytosol and are consistent with a model ofO-acetyl sialic acid biosynthesis involving both cytosolic and smooth membrane sites ofO-acetylation.
32 citations
TL;DR: It is essential to desialylate and to defucosylate the glycans prior to application to L-PHA-agarose to obtain reliable information on the relative occurrence of tri- and tetra-antennary glycopeptides.
Abstract: The effects of branching and substitution of branches by sialic acid and fucose on the interaction ofN-linked glycopeptides and related oligosaccharides with immobilizedPhaseolus vulgaris leukoagglutinating lectin (L-PHA) were examined. Asialo bi-, tri-and tetra-antennary glycans were all retarded but to different extents on a long column of L-PHA-agarose. Asialo tri- and tetra-antennary glycans containing the pentasaccharide unit Galβ1-4GlcNAcβ1-2[Galβ1-4GlcNAcβ1-6]Man were strongly retarded, whereas asialo bi- and tri-antennary glycans lacking the Galβ1-4GlcNAcβ1-6 branch were only weakly retarded. In all instances the interaction with the lectin was completely abolished when either α(2–6)-linkedN-acetylneuraminic acid or α(1–3)-linked fucose was present at the galactose orN-acetylglucosamine residue of the Galβ1-4GlcNAcβ1-6Manα1-6 branch, respectively. The same substitutions on the Galβ1-4GlcNAcβ1-6Manα1-6 branch decreased but did not abolish the affinity of the lectin for the glycans. The presence of NeuAcα2-6 and Fucα1-3 on the other two branches did not interfere with the binding of the glycans to L-PHA. Furthermore, it appeared that the presence of the Manβ1-4GlcNAc unit is requried for interaction with the lectin. In order to obtain reliable information on the relative occurrence of tri- and tetra-antennary glycopeptides, this study shows that it is essential to desialylate and to defucosylate the glycans prior to application to L-PHA-agarose.
28 citations
TL;DR: Results illustrate that in some structures, like the epithelial cells of sweat ducts, both the products ofH andSe genes can contribute to the synthesis of the same Leb structure.
Abstract: Based on the genetic model proposing thatH andSe are two structural genes, we predicted that the red cell H-deficient, salivary ABH secretor phenotype should be found on Reunion island, where a large series of H-deficient non-secretor families have been previously described. Two such Reunion individuals are now reported. POU [Ah, Le(a−b+), secretor of A, H, Lea and Leb in saliva] and SOU [Oh, Le(a−b+), secretor of H, Lea and Leb in saliva]. Both are devoid of H α-2-fucosyltransferase activity in serum. In addition, the preparation of total non-acid glycosphingolipids from plasma and red cells of POU revealed the type 1ALeb heptaglycosylceramide and small amounts of the monofucosylated type 1 A hexaglycosylceramide. Both glycolipids possess an H structure probably synthesised by the product of theSe gene. No other blood group A glycolipids, with types 2, 3 or 4 chains, normally present in the presence of the product of theH gene, were found on red cells or plasma of POU.
TL;DR: Sixteen asparagine-linked oligosaccharides obtained from human α1-acid glycoprotein and fibrinogen, hen ovomucoid and ovalbumin, and bovine fetuin, fibr in and thyroglobulin by hydrazinolysis, mild acid hydrolysis and glycosidase treatment are characterized.
Abstract: Sixteen asparagine-linked oligosaccharides ranging in size from (Man)2(GlcNAc)2 (Fuc)1 to (GlcNAc)6(Man)3(GlcNAc)2 were obtained from human α1-acid glycoprotein and fibrinogen, hen ovomucoid and ovalbumin, and bovine fetuin, fibrin and thyroglobulin by hydrazinolysis, mild acid hydrolysis and glycosidase treatment. The oligosaccharides hadN-acetylglucosamine at the reducing termini and mannose andN-acetylglucosamine residues at the non-reducing termini and were prepared for use asN-acetylglucosaminyltransferase substrates. Purification of the oligosaccharides involved gel filtration and high performance liquid chromatography on reverse phase and amine-bonded silica columns. Structures were determined by 360 MHz and 500 MHz proton nuclear magnetic resonance spectroscopy, fast atom bombardment-mass spectrometry and methylation analysis. Several of these oligosaccharides have not previously been well characterized.
TL;DR: The N-linked carbohydrate chains of the β-subunit of highly purified urinary human chorionic gonadotropin have been re-investigated in this article, and the primary structures of the latter carbohydrate chains have been determined by 500-MHz 1H-NMR spectroscopy to be
Abstract: TheN-linked carbohydrate chains of theβ-subunit of highly purified urinary human chorionic gonadotropin have been re-investigated. The oligosaccharides were released enzymatically by peptide-N
4-(N-acetyl-β-glucosaminyl)asparagine amidase-F, and fractionated by a combination of FPLC and HPLC. As a result of the application of improved fractionation methods, apart from the earlier reported carbohydrate chains, also small amounts of trisialo tri- and tri′-antennary oligosaccharides were found. The primary structures of the latter carbohydrate chains have been determined by 500-MHz1H-NMR spectroscopy to be
TL;DR: In this paper, the structure of a new nonasaccharide isolated from human milk has been investigated using methylation analysis, FAB-MS and 1H-and 13C-NMR spectroscopy.
Abstract: The structure of a new nonasaccharide isolated from human milk has been investigated. By using methylation analysis, FAB-MS and1H-and13C-NMR spectroscopy as basic methods of structural investigation, this oligosaccharide was identified as VI2-α-Fuc,V4α-Fuc,III3-α-Fuc-p-lacto-n-hexaose: Fucα1-2Galβ1-3[Fucα1-4]GlcNAcβ1-3Galβ1-4[Fucα1-3]GlcNAcβ1-3Galβ1-4Glc.
TL;DR: The equivalence zones (regions of maximum precipitation) of the precipitin curves of Con A and the carbohydrates indicate that certain oligomannose and bisected hybrid type glycopeptides are bivalent for lectin binding, while the nonbisected analogs are univalent.
Abstract: The affinity of concanavalin A (Con A) for simple saccharides has been known for over 50 years. However, the specificity of binding of Con A with cell-surface related carbohydrates has only recently been examined in detail. Brewer and coworkers [J Biol Chem (1986) 261:7306–10; J Biol Chem (1987) 262:1288–93; J Biol Chem (1987) 262:1294–99] have recently studied the binding interactions of a series of oligomannose and bisected hybrid type glycopeptides and complex type glycopeptides and oligosaccharides with Con A. The relative affinities of the carbohydrates were determined using hemagglutination inhibition measurements, and their modes of binding to the lectin examined by nuclear magnetic relaxation dispersion (NMRD) spectroscopy and quantitative precipitation analyses. The equivalence zones (regions of maximum precipitation) of the precipitin curves of Con A and the carbohydrates indicate that certain oligomannose and bisected hybrid type glycopeptides are bivalent for lectin binding. From the NMRD and precipitation data, two protein binding sites on each glycopeptide have been identified and characterized. Certain bisected complex type oligosaccharides also bind and precipitate Con A, while the corresponding nonbisected analogs bind but do not precipitate the protein. The precipitation data indicate that the bisected complex type oligosaccharides are also bivalent for lectin binding, while the nonbisected analogs are univalent. The NMRD and precipitation data are consistent with different mechanisms of binding of nonbisected and bisected complex type carbohydrates to Con A, including different conformations of the bound saccharides.
TL;DR: Three chemical transformations of oligosaccharide 1-deoxy-1-(4-trifluoroacetamidophenyl)aminoalditols are described in this article.
Abstract: Three chemical transformations of oligosaccharide 1-deoxy-1-(4-trifluoroacetamidophenyl)aminoalditols are described. 1) Oxidation with hydrogen peroxide to give the corresponding reducing oligosaccharides. 2) Oxidation with cerium ammonium nitrate to give the corresponding 1-amino-1-deoxyalditols. 3) Treatment with acetic anhydride to give the correspondingN-acetylated derivatives, which are more stable towards oxidation.
TL;DR: This is the first synthetic sialic acid analogue, which can be activated and transferred to glycoprotein, but is not a sialidase (EC 3.2.1.18) substrate.
Abstract: We demonstrate that 9-amino-NeuAc transferred to asialo-α1-acid glycoprotein resists cleavage by bacterial, viral and mammalian sialidases. This is the first synthetic sialic acid analogue, which can be activated and transferred to glycoprotein, but is not a sialidase (EC 3.2.1.18) substrate.
TL;DR: The trisaccharide 2-(p-trifluoroacetamidophenyl)ethyl 2-O-(α-l-fucopyranosyl)-3-O(α-d-galactopyranoyl)-β-D-Galactophyranoside, corresponding to the human blood group B determinant, was synthesized in this article.
Abstract: The trisaccharide 2-(p-trifluoroacetamidophenyl)ethyl 2-O-(α-l-fucopyranosyl)-3-O-(α-d-galactopyranosyl)-β-d-galactopyranoside, corresponding to the human blood group B determinant, was synthesized. Thioglycosides activated by sulfuryl chloride/trifluoromethanesulfonic acid were used as glycosyl donors in the construction of the three glycosidic linkages.
TL;DR: Phosphorylation is not a prerequisite to secretion of xyloside-induced glycosaminoglycan chains in cultured fibroblasts and exhaustive digestion with chondroitin AC and ABC lyases yields an unphosphorylated linkage region tetrasaccharide in the majority of all polysaccharide chains.
Abstract: Secretion ofp-nitrophenyl-β-xyloside-induced glycosaminoglycan chains in cultured fibroblasts is considered to involve transport through the endoplasmic reticulum and the Golgi apparatus Purified glycosaminoglycans from fibroblast secretions contain small amounts of covalently bound [32P]phosphate However, exhaustive digestion with chondroitin AC and ABC lyases yields an unphosphorylated linkage region tetrasaccharide in the majority of all polysaccharide chains The phosphate label is associated predominantly with material of the expected behavior of linkage region hexasaccharides Thus, phosphorylation is not a prerequisite to secretion of xyloside-induced glycosaminoglycan chains
TL;DR: The exposure of glycolipids in Pk and p red cells was studied and minor components with longer oligosaccharide chains were readily labeled in p cells by the galactose oxidase/NaB3H4 method.
Abstract: The exposure of glycolipids in Pk and p red cells was studied by the galactose oxidase/ NaB2H4 and galactose oxidase/NaB3H4 surface labeling techniques. The major glycolipid in Pk cells, ceramide trihexoside was efficiently labeled when high amounts of galactose oxidase were used. In contrast, the major glycolipid in p cells, ceramide dihexoside was not oxidized by galactose oxidase. However, minor components with longer oligosaccharide chains were readily labeled in p cells by the galactose oxidase/NaB3H4 method.
TL;DR: New types of neoglycoproteins coupled with ovalbumin-derived asparagine oligosaccharides, including β-casein derivatives and the AAT-PG complex, were tested for their inhibitory effect on binding of bovine serum albumin derivatized with thiomannoside by rabbit alveolar macrophages, suggesting that proper orientation of the oligosACcharides on the protein can affect the receptor-ligand interaction.
Abstract: New types of neoglycoproteins, β-caseins coupled with ovalbumin-derived asparagine oligosaccharides (AO), aspartate aminotransferase-phosphopyridoxylated AO complex (AAT-PG), and streptavidin-biotinylated AO complex (SA-BAO), were tested for their inhibitory effect on binding of bovine serum albumin derivatized with thiomannoside, Man-AI-BSA [Lee YC, Stowell CP, Krantz MJ (1976) Biochemistry 15:3956–63] by rabbit alveolar macrophages. The β-casein derivatives and the AAT-PG complex increased binding affinity as the number of oligosaccharide chains attached was increased. Their inhibitory potencies were closely related to those of the Man-Al-BSA derivatives [Hoppe CA, Lee YC (1983) J Biol Chem 258:14193–99] on the basis of terminal mannose density. The SA-BAO complex containing three AO chains gave stronger inhibitory potency than the β-casein derivative with three AO residues, suggesting that proper orientation of the oligosaccharides on the protein can affect the receptor-ligand interaction.
TL;DR: Oligosaccharides from theO-polysaccharide chain of theSalmonella typhi 253Ty lipopolysaccharides (LPS) were prepared from delipidated LPS by digestion with bacteriophage P22.
Abstract: Oligosaccharides from theO-polysaccharide chain of theSalmonella typhi 253Ty lipopolysaccharide (LPS) were prepared from delipidated LPS by digestion with bacteriophage P22. The oligosaccharides were separated by gel chromatography into fractions representing monomers to polymers of the basic tetrasaccharide repeating unit. Fractions containing the dimer and the trimer were analysed by fast atom bombardment-mass spectrometry as methylated alditols. The mass spectra clearly showed heterogeneity in terms ofd-glucose substitution of thed-galactose residue in the tetrasaccharide repeating unit: dimers with none, one, or twod-glucosyl branches and trimers with none, one, two, or threed-glucosyl branches were found. This suggests a randomd-glucosylation of theO-polysaccharide chain ofS. typhi 253Ty.
TL;DR: A previously unknown substance, mannosyl-β(1-4)-N-acetylglucosaminyl β(1 -N)-urea, has been isolated from the urine of patients with β-mannosidosis in addition to the main metabolite MANNOSOIL as mentioned in this paper, which was carried out by fast atom bombardment mass spectrometry and high-resolution 1H-nuclear magnetic resonance spectroscopy at 500 MHz.
Abstract: A previously unknown substance, mannosyl-β(1–4)-N-acetylglucosaminyl-β(1-N)-urea, has been isolated from the urine of patients with β-mannosidosis in addition to the main metabolite mannosyl-β(1–4)-N-acetylglucosamine Structural investigation was carried out by fast atom bombardment mass spectrometry and high-resolution1H-nuclear magnetic resonance spectroscopy at 500 MHz It was postulated that the occurrence of this carbohydrate-urea conjugate in urine results mainly from urine handling
TL;DR: Interestingly, the modification rendered the sialic acid resistant to a variety of sialidases, suggesting that the introduction of an amino compound into the polyol chain of sIALic acid has a stabilizing effect on the ketosidic linkage of the sugar.
Abstract: A method for modifying and isotopic labeling the sialyl moiety of sialoglycoproteins is described. The basis of the procedure is the reductive amination of the exocyclic aldehyde group, generated on sialic acid by mild periodate oxidation, with a variety of amino compounds and sodium cyanoborohydride. Optimal conditions were selected to obtain maximum modification of sialic acid and minimal non-specific incorporation of the amino compound (glycine). The glycine modified model glycoproteins (α1-acid glycoprotein, fetuin) yielded single homogenous peaks upon gel filtration and on ion exchange chromatography. On gel electrophoresis a major band accounting for 92–98% of the modified glycoprotein and two minor bands consisting of dimers and trimers of the glycoprotein were observed. The modification did not alter the ability of the sialoglycoproteins to bind to wheat germ agglutinin-Sepharose or to interact with antibodies. The modified sialic acid was only partially released by mild acid hydrolysis suggesting that the introduction of an amino compound into the polyol chain of sialic acid has a stabilizing effect on the ketosidic linkage of the sugar. Interestingly, the modification rendered the sialic acid resistant to a variety of sialidases. The potential uses of this modification procedure include 1) the introduction of different isotopic labels (3H,14C,35S,125I) into the sialic acid moiety of glycoproteins; 2) the preparations of biologically active sialoglycoprotein (hormones, enzymes, co-factors) with increased circulating half-lives in animals; 3) preparation of substrates to search for endoglycosidases; 4) the direct comparison of sialoglycoprotein patterns obtained in small amounts from normal and pathological cells or tissues, and 5) the isolation and purification of cell surface sialoglycoproteins.
TL;DR: A novel procedure is described for the measurement of the galactosaminitol evolving from the protein linkage of oligosaccharides and of keratan sulphate.
Abstract: A method is described for the measurement ofN-acetylgalactosamine,N-acetylglucosamine, galactose, mannose and xylose present in the different carbohydrate chains of cartilage proteoglycans (PG) Bovine articular cartilage PG samples corresponding to the minimum of 1 nmol of each monosaccharide were reproducibly quantified following hydrolysis with 2 M HCl and derivatization into alditol acetates An on-column injection mode and an OV-1701 fused silica capillary column were used for chromatography Alkaline borohydride treatment of the PG was exploited to reduce the acid labile xylose in the base of the chondroitin sulphate chain into more stable xylitol, allowing the assay of chondroitin sulfate chain length as anN-acetylgalactosamine/xylose ratio A novel procedure is described for the measurement of the galactosaminitol evolving from the protein linkage of oligosaccharides and of keratan sulphate
TL;DR: In this article, a method for the synthesis of oligosaccharide components of glycosphingolipids using benzyl β-d-lactoside was proposed.
Abstract: The preparation of benzyl 2,3,6,2′,6′-penta-O-benzyl-β-d-lactoside, which is a key intermediate for chemical synthesis of oligosaccharide components of glycosphingolipids, was achieved by an improved method. The 3′-O-p-methoxybenzyl and 3′-O-methyl derivatives were prepared from benzyl 2,3,6,2′,6′-penta-O-benzyl-β-d-lactoside through stannylation. By using benzyl β-d-lactoside as starting material, benzyl 3′-O-methyl-, 3′-O-benzyl- and 3′-O-p-methoxybenzyl-β-d-lactoside were regioselectively synthesized using the same procedure.
TL;DR: The tetrasaccharide 2-(p-trifluoroacetamidophenyl)ethylO-α-l-fucopyranosyl-(1-3)-O-(2-acetamido-2-deoxy-β-d-glucopyrusyl)-(1−3)O −β −d-galactopyranoyl-( 1−4)-β −glucophyranoside was synthesized from thioglycoside intermediates as mentioned in this paper.
Abstract: The tetrasaccharide 2-(p-trifluoroacetamidophenyl)ethylO-α-l-fucopyranosyl-(1–3)-O-(2-acetamido-2-deoxy-β-d-glucopyranosyl)-(1–3)-O-β-d-galactopyranosyl-(1–4)-β-d-glucopyranoside was synthesized from thioglycoside intermediates. The key step was a methyl triflate promoted glycosidation of a lactose-derived 3′,4′-diol with a disaccharide thioglycoside to give a β(1–3)-linked tetrasaccharide derivative in 67% yield.
TL;DR: Purification of three galactomannans from fenugreek, guar andPoinciana pulcherrima seeds, a galactoglucomannan fromCrotalaria saltiana seed and a polysaccharide from the albumin gland of the snail Littorina littorea has been achieved by affinity chromatography on a lectin-Sepharose column.
Abstract: An α-d-galactosyl-binding lectin fromArtocarpus integrifolia (jackfruit) seeds has been coupled to cyanogen bromide-activated Sepharose 4B. Purification of three galactomannans from fenugreek, guar andPoinciana pulcherrima seeds, a galactoglucomannan fromCrotalaria saltiana seed and a polysaccharide from the albumin gland of the snailLittorina littorea has been achieved by affinity chromatography on a lectin-Sepharose column. The recovery of the polysaccharides absolutely devoid of protein is about 40%.
TL;DR: In this article, the azidonitration procedure was used to extract 3,4,6-tri-O-acetyl-2-azido-2deoxy-D-galacto derivatives from 3, 4, 6-tri O-acetyyl-1, 5-a n hydro-2d eoxy-d-lyxo-h ex-l-e n itol.
Abstract: Galactosamine and its derivatives are diff icult to isolate from natural sources, therefore several synthetic routes [1-8] to such derivatives have been reported. The most useful of these is the azidonitration procedure which, as reported by Lemieux etal. [8], gives easy access to 3,4,6-tri-O-acetyl-2-azido-2-deoxy-D-galacto derivatives from 3,4,6-tri-O-acetyl1,5-a n hyd ro-2-d eoxy-D-lyxo-h ex-l-e n itol.
TL;DR: The elution patterns obtained for these distinct proteoglycans closely resembled those of heparin and oversulfated chondroitin sulfate E standards, and clearly demonstrated the importance of sulfate density both for the affinity to fibronectin and collagen.
Abstract: 35S-labelled chondroitin sulfate proteoglycans isolated from conditioned media of cultured human monocytes (day 1in vitro) and monocyte-derived macrophages (day 6in vitro) were chromatographed on columns of immobilized fibronectin and collagen, respectively. The elution profiles prior to and after alkali treatment were compared with those of standards chondroitin 4-sulfate and chondroitin sulfate E and heparin. The day 635S-proteoglycans have a higher sulfate density than the day 1 species, but this difference did not affect the elution profiles after chromatography on collagen-Sepharose, whereas the day 6 proteoglycans bound more firmly than the day 1 fraction to fibronectin-Sepharose. The elution patterns obtained for these distinct proteoglycans closely resembled those of heparin and oversulfated chondroitin sulfate E standards, and clearly demonstrated the importance of sulfate density both for the affinity to fibronectin and collagen. Neither day 1 nor day 635S-proteoglycans were found to interact with hyaluronate.