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1.
An acidic heteropolysaccharide preparation derived from the mycelium of Fusarium sp. M7-1 was fractionated into two fractions, precipitable and nonprecipitable, by treatment with cetyltrimethylammonium bromide (Cetavlon). These two fractions were further purified to apparent homogeneity on ultracentrifugation by treatment with charcoal and gel filtration chromatographies. Two glycoproteins, precipitable GP I and nonprecipitable GP II, were obtained. The molecular weights of GP I and GP II were estimated to be about 8.8 x 10(4) and 3.7 x 10(4), respectively, on gel filtration chromatography. Both GP I and GP II contained a high proportion of serine and threonine. Treatment of GP I and GP II with alkaline solution resulted in an increase in absorbance at 240 nm. Alkaline borohydride treatment markedly decreased the number of seryl and threonyl residues and resulted in an increase in alanine and the formation of 2-aminobutyric acid. It also resulted in release of low and high molecular weight carbohydrate chains. From these results, we conclude that both GP I and GP II are glycoproteins with carbohydrate chains attached to the protein moiety through O-glycosidic linkages to the hydroxyl group of serine and/or threonine.  相似文献   

2.
The primary structures of the O-glycosidically linked oligosaccharides isolated from glycoproteins GP I and GP II of Fusarium sp. M7-1 were established. The oligosaccharides released by alkaline borohydride treatment from the glycoproteins were purified by Bio-Gel P-4 and HPLC. This approach resulted in one monosaccharide and seven oligosaccharides. Their primary structures were resolved mainly by NMR spectrometry in combination with methylation mass spectrometry and fast atom bombardment mass spectrometry. The following structures have been determined. [formula: see text].  相似文献   

3.
Water-soluble polysaccharide fractions VO1-VO4 were isolated from the squeezed berries of snowball tree (Viburnum opulus) by successive extraction with water at various temperatures and pH and with aqueous solutions of ammonium oxalate. These fractions were purified by ion-exchange chromatography on DEAE cellulose, and the homogeneity of the purified polysaccharides was determined by gel filtration on Sephacryl S-500. Acidic polysaccharides close to pectins in their sugar composition were found in all the extracts (fractions VO1-1, VO2-1, VO3-2, and VO4-2). Residues of galacturonic acid, galactose, arabinose, and (to a lesser extent) rhamnose are their main constituents. Neutral polysaccharides composed mainly of galactose and mannose residues were additionally found in fractions extracted with acidified water (pH 4.0) and with aqueous ammonium oxalate solutions. Partial acidic hydrolysis and digestion with pectinase of acidic polysaccharides indicated that their carbohydrate backbone consists of alpha-1,4-linked residues of D-galacturonic acid. NMR spectra of acidic polysaccharides (fractions VO3-2 and VO3-3) confirmed this and demonstrated that their side oligosaccharide chains are composed of beta-1,4-linked galactopyranose residues and of terminal and 2,5- and 3,5-substituted residues of alpha-arabinofuranose at a Gal: Ara ratio of 3:1. Some polysaccharides from V. opulus were found to possess an immunostimulating activity: they enhance phagocytosis, in particular, the phagocytic index and the secretion of lysosomal enzymes with peritoneal macrophages. Calcium ions were found to be necessary for the appearance of the stimulating effect of acidic polysaccharides from V. opulus.  相似文献   

4.
The structures of high molecular weight sulfated oligosaccharide chains in mucins purified from the sputum of a patient with cystic fibrosis and blood group H determinant were established. Reduced oligosaccharides released by treatment with alkaline borohydride were separated by ion exchange chromatography on DEAE-Agarose and a fraction containing multisulfated chains was further purified by lectin affinity chromatography to completely remove small amounts of sialylated chains. A major sulfated oligosaccharide fraction containing chains with an average of 160 to 200 sugar residues was isolated by gel filtration on BioGel P-10 columns and individual subfractions were characterized by methylation analysis, periodate oxidation and sequential glycosidase digestion before and after desulfation. Carbohydrate analysis yielded Fuc, Gal and GldNAc in a ratio of 1:2:2.1 and only one galactosaminitol residue for every 160-to 200 sugar residues. The average molecular weight of oligosaccharide chains in these fractions was between 27,000 and 40,000 daltons. Structural analysis showed that these high molecular weight chains contained varying amounts of the repeating unit shown in the following oligosaccharide. Only one in about every 10 repeating units contained sulfate esters.Several shorter chains which contain 2 to 3 sulfate esters were also isolated from this multisulfated oligosaccharide fraction. The structures proposed for these oligosaccharides indicate that they are lower molecular weight chains with the same general structure as those found in the high molecular weight sulfated oligosaccharides. Taken collectively, the results of these studies show that a major sulfated oligosaccharide fraction in resporatory mucin purified from the mucus of patients with cystic fibrosis contains high molecular weight branched chains that consist of a repeating oligosaccharide sequence with sulfate linked to the 6 positions of galactose and possibly GlcNAc residues in the side chains.  相似文献   

5.
Water-soluble polysaccharide fractions VO1–VO4 were isolated from the squeezed berries of the snowball tree (Viburnum opulus) by successive extraction with water at various temperatures and pH and with aqueous solutions of ammonium oxalate. These fractions were purified by ion-exchange chromatography on DEAE cellulose, and the homogeneity of the purified polysaccharides was determined by gel filtration on Sephacryl S-500. Acidic polysaccharides close to pectins in their sugar composition were found in all the extracts (fractions VO1-1, VO2-1, VO3-2, and VO4-2). Residues of galacturonic acid, galactose, arabinose, and (to a lesser extent) rhamnose are their main constituents. Neutral polysaccharides composed mainly of galactose and mannose residues were additionally found in fractions extracted with acidified water (pH 4.0) and with aqueous ammonium oxalate solutions. Partial acidic hydrolysis and digestion with pectinase of acidic polysaccharides indicated that their carbohydrate backbone consists of α-1,4-linked residues ofD-galacturonic acid. NMR spectra of acidic polysaccharides (fractions VO3-2 and VO3-3) confirmed this and demonstrated that their side oligosaccharide chains are composed of β-1,4-linked galactopyranose residues and of terminal and 2,5- and 3,5-substituted residues of α-arabinofuranose at a Gal : Ara ratio of 3 : 1. Some polysaccharides fromV. opulus were found to possess an immunostimulating activity: they enhance phagocytosis, in particular, the phagocytic index and the secretion of lysosomal enzymes with peritoneal macrophages. Calcium ions were found to be necessary for the appearance of the stimulating effect of acidic polysaccharides fromV. opulus.  相似文献   

6.
Human gastric mucin from aspirates has been degraded by proteolysis to afford a soluble glycopolypeptide which, when purified by gel filtration on Bio-Gel P 150 and chromatography on Ecteola cellulose, was essentially free from mannose. Structural information on the oligosaccharide chains attached to the polypeptide core was obtained by mild hydrolysis with acid, Smith degradation, and degradation with sodium phosphate-borohydride, both before and after the removal of fucose by controlled, acid hydrolysis. A number of oligosaccharides were isolated and purified by gel and paper chromatography. Minimal degradation due to base-catalysed peeling reactions was experienced with the sodium phosphate-borohydride technique. The oligosaccharides have been characterised and structures proposed for the various side-chains present in human gastric mucin.  相似文献   

7.
The structures of the major sialylated oligosaccharide chains in swine tracheal mucin glycoprotein were established. The oligosaccharide chains were released by treatment with alkaline borohydride and isolated by gel filtration on Bio-Gel P6 columns and chromatography on DEAE-cellulose. The neutral oligosaccharide chains in this glycoprotein have been characterized in previous studies (Rana, S.S., Chandrasekaran, E.V., Kennedy, J., and Mendicino, J. (1984) J. Biol. Chem. 259, 12899-12907; Chandrasekaran, E.V., Rana, S.S., Davila, M., and Mendicino, J. (1984) J. Biol. Chem. 259, 12908-12914). The present study reports the isolation of four monosialylated chains ranging in length from 6 to 14 sugar units, two disialylated chains containing 6 and 12 sugar units, and one trisialylated chain containing 9 sugar units. The structure of the sialylated oligosaccharides was determined by permethylation analysis and sequential hydrolysis with specific exoglycosidases. The following structures (where GalNAcol is N-acetylgalactosaminitol) were assigned to these oligosaccharides.  相似文献   

8.
Four glycopeptides (I, IIA, IIB, III) with different oligosaccharide structures were isolated from purified mouse thymocyte Thy-1 glycoprotein. The glycoprotein was digested with Pronase, and the glycopeptide fraction was isolated by gel filtration and acetylated with [3H]acetic anhydride. The different glycan structures were separated by affinity chromatography on concanavalin A-Sepharose 4B and lentil lectin-Sepharose 4B. Size determinations of intact and exoglycosidase- and endoglycosidase-digested glycopeptides were performed by gel filtration on Bio-Gel P-6, calibrated with glycopeptides of known structure. On the basis of these experiments and on the behaviour of the glycopeptides on the lectin columns, the following structures of the oligosaccharide chains were proposed: I, triantennary 'complex-type' with terminal fucose; IIA, biantennary 'complex-type' without fucose; IIB, biantennary 'complex-type' with fucose; III, a mixture of 'high-mannose' chains containing either five or six mannose residues (approx. 50% of each). Amino acid analysis of the glycopeptides showed that the predominant oligosaccharide at glycosylation-site Asn-23 was of 'high-mannose' type, whereas the other two sites (Asn-75 and Asn-99) were glycosylated with 'complex-type' chains. Both these sites were shown to be variably glycosylated. The major glycans linked to Asn-75 were of structures I and IIB, whereas all three 'complex-type' chains were represented at Asn-99. The results presented explain the previously reported carbohydrate heterogeneity of thymocyte Thy-1 glycoprotein.  相似文献   

9.
Two trypsin inhibitors from acid-treated buffalo seminal plasma were purified by gel filtration and affinity chromatography. These acid-stable trypsin inhibitors having charge heterogeneity were homogeneous with respect to size as revealed by gel filtration and SDS-PAGE. Gel filtration data suggest molecular weight value of 9,900 Da for inhibitor I and 10,900 Da for inhibitor II. Molecular weight estimated by SDS-PAGE was found to be 10,600 Da and 11,200 Da for inhibitors I and II, respectively. The hydrodynamic properties such as Stokes radii (1.58 nm and 1.62 nm); intrinsic viscosity (2.5725 ml/g and 2.5025 ml/g) and diffusion coefficient (13.499 x 10(-11) m2/sec. and 13.166X10(-11) m2/sec) respectively for inhibitor I and II were determined by analytical gel filtration. These inhibitors were fairly thermostable and could not be stained by PAS reagent. Both the inhibitors were found to inhibit buffalo acrosin but not bovine chymotrypsin.  相似文献   

10.
11.
The structure of five sulfated oligosaccharide units of highly anionic tracheobronchial mucous glycoproteins, isolated from a cystic fibrosis patient's sputum, were established. Reduced oligosaccharides (84%) were released under alkaline borohydride conditions, and the acidic oligosaccharides (63%) were isolated by Dowex 1-X2 chromatography. Following the removal of acidic oligosaccharides possessing N-acetylneuraminic acid and L-fucose by lectin affinity chromatography a heterogeneous mixture of sulfated oligosaccharides was obtained. From this fraction, five short chain monosulfated oligosaccharides (S-I to S-V) were purified by sequential separation by SynChroprep AX300 anion exchange high pressure liquid chromatography, gel filtration on Bio-Gel P-2, and high voltage paper electrophoresis. Based on the results of carbohydrate composition, sequential exoglycosidase degradation, permethylation analysis, lectin affinity chromatography, and periodate oxidation, the following structures (where GalNAcol is N-acetylgalactosaminitol) were proposed for these oligosaccharides. (formula; see text)  相似文献   

12.
Cl.16E, a stably differentiated clonal derivative of the human colonic cancer cell line HT29, was used to investigate the structure of oligosaccharide chains of mucins in colonic cancer. Secretory mucins were purified by equilibrium density gradient centrifugation in CsCl. Oligosaccharide side chains were isolated after beta-elimination. Compositional analysis of oligosaccharide-alditols performed after purification by gel filtration on a Bio-gel P-6 column showed 1) that GalNAc residues were located exclusively at the reducing ends of the chains, and 2) that fucose was absent from the preparation. Oligosaccharide-alditols were separated by high performance liquid chromatography (HPLC) on quaternary amine packings into a minor neutral fraction representing about 6.5% by weight of released oligosaccharides and four acidic fractions. Two acidic fractions, namely FI and FII encompassing mono- and disialylated structures, respectively, and containing 78% of total oligosaccharide alditols, were separated by HPLC. Structural determinations were carried out using methylation analysis, 1H NMR spectroscopy, and fast atom bombardment-mass spectrometry. Twelve oligosaccharide structures were determined which ranged in size from 3 to 8 residues. These oligosaccharides were based on core types 1, 2, and 4. Elongation of oligosaccharide chains was terminated by addition of sialic acid in alpha 2-3 linkage to Gal beta 1-3R and to Gal beta 1-4R residues. The predominant structure was a hexasaccharide (fraction FII-4). This contrasts with normal colonic mucins whose oligosaccharides were previously found to be based on core 3 structures and carry sialic acids in alpha (2-6) linkage to Gal beta 1-3R, to Gal beta 1-4R, and to GalNAc alpha-R (Podolsky, D.K. (1985) J. Biol. Chem. 260, 8262-8271; Podolsky, D.K. (1985) J. Biol. Chem. 260, 15510-15515). Collectively our findings suggest that Cl.16E colon cancer cells are able to synthesize mucin oligosaccharides of gastric type whose elongation is truncated by premature sialylation.  相似文献   

13.
Human alpha1-microglobulin (alpha1-m; also called protein HC), a glycoprotein belonging to the lipocalin superfamily, was isolated by sequential anion-exchange chromatography and gel filtration from the urine of hemodialized patients and from amniotic fluid collected in the week 16-18 of pregnancy. The carbohydrate chains of the protein purified from the two sources, which are organized in two Asn-linked and one Thr-linked oligosaccharides, were structurally characterized using matrix-assisted laser desorption ionization and electrospray mass spectrometry. The glycans attached to Thr5 are differently truncated NeuHexHexNAc sequences, and O-glycosylation in the amniotic fluid protein is only partial. Asn96 has both diantennary and triantennary structures attached in the case of urinary alpha1-m and only diantennary glycans in the amniotic fluid protein. The main carbohydrate units attached to Asn17 are in both proteins monosialylated and disialylated diantennary glycans. The position of the oligosaccharide chains in a three-dimensional model of the protein, produced using the automated Swiss-Model service, is also discussed.  相似文献   

14.
Human respiratory mucin glycoproteins from patients with cystic fibrosis were purified and oligosaccharide chains were released by treatment with alkaline borohydride. A neutral oligosaccharide alditol fraction was isolated from mucin obtained from a patient with A blood group determinant by chromatography on DEAF-cellulose and individual oligosaccharide chains were then isolated by gel filtration on BioGel P-6 columns and high performance liquid chromatography with gradient and isocratic solvent systems. The structures of the purified oligosaccharides were determined by methylation analysis, sequential glycosidase digestion and H-NMR spectroscopy. The amount of each chain was determined by compositional analysis. A wide array of discrete branched oligosaccharide structures that contain from 3 to 22 sugar residues were found. Many of the oligosaccharides are related and appear to be precursors of larger chains. The predominant branched oligosaccharides which accumulate contain terminal blood group H (Fuc2Ga14) or blood group A (Fuc2(Ga1NAc3) (Ga14) determinants which stop further branching and chain elongation. The elongation of oligosaccharide chains in respiratory mucins occurs on the 3-linked G1cNAc at branch points, whereas the 6-linked GlcNAc residue ultimately forms short side chains with a Fuc2 (Ga1NAc3) Gal4 G1cNAc6 structure in individuals with A blood group determinant.The results obtained in the current studies further suggest that even higher molecular weight oligosaccharide chains with analogous branched structures are present in some human respiratory mucin glycoproteins. Increasing numbers of the repeating sequence shown in the oligosaccharide below is present in the higher molecular weight chains. {ie75-1} This data in conjunction with our earlier observations on the extensive branching of these oligosaccharide chains helps to define and explain the enormous range of oligosaccharide structures found in human and swine respiratory mucin glycoproteins. Comparison of the relative concentrations of each oligosaccharide chain suggest that these oligosaccharides represent variations of a common branched core structure which may be terminated by the addition of a2-linked fucose to the 3/4 linked galactose residue at each branch point. These chains accumulate and are found in the highest concentrations in these respiratory mucins.  相似文献   

15.
The seed mucilage from Plantago major L. contains acidic heteroxylan polysaccharides. For further structural analysis, oligosaccharides were generated by partial acid hydrolysis and then isolated by high-pH anion-exchange chromatography (HPAEC). Each HPAEC fraction was shown by ESMS to contain one major oligosaccharide and several minor components. Partial structures of the oligosaccharides were determined using GC-MS, ESMS and ES tandem mass spectrometry (ESMS/MS). A (1-->4)-linked xylan trisaccharide and (1-->3)-linked xylan oligosaccharides with DP 6-11 suggested that the backbone of the heteroxylan polysaccharide consisted of blocks of (1-->4)-linked and (1-->3)-linked Xylp residues. A (1-->2)-linked Xylp disaccharide and a branched tetrasaccharide were also found, revealing that single Xylp residues are linked to the O-2 of some of the (1-->4)-linked Xylp residues in the backbone. In addition, our results confirm the presence of side chains consisting of the disaccharide GlcpA-(1-->3)-Araf.  相似文献   

16.
We isolated four nitroreductases from Bacteroides fragilis GAI0624 and examined their physicochemical and functional properties. Two major enzyme activities were found in the adsorbed and unadsorbed fractions from DEAE-cellulose column chromatography. The adsorbed fraction was subjected to Sephadex G-200 column chromatography, and two further activities were separated. One has high nitroreductase activity (nitroreductase I), and the other has low activity and relatively high molecular weight (nitroreductase III). The nitroreductase I fraction was subjected to hydroxylapatite and chromatofocusing column chromatography, and nitroreductase I was purified about 416-fold with a yield of 6.77%. The unadsorbed fraction from DEAE-cellulose column chromatography was subjected to Sepharose 2B and Sepharose 6B column chromatography. Two enzyme activities were obtained by the Sepharose 6B column chromatography. One has high activity (nitroreductase II), and the other has low activity (nitroreductase IV). Nitroreductase II was rechromatographed by Sepharose 6B gel filtration and purified about 178-fold with a yield of 9.65%. The four enzymes (nitroreductases I, II, III, and IV) were shown to be different by several criteria. Their molecular weights, determined by gel filtration, were 52,000, 320,000, 180,000, and 680,000, respectively. The substrate specificity, the effect on mutagenicity of mutagenic nitro compounds, of nitroreductases I, III, and IV was relatively high for 1-nitropyrene, dinitropyrenes, and 4-nitroquinoline 1-oxide, respectively, but nitroreductase II had broad specificity. Nitroreductase activity required a coenzyme; nitroreductases II, III, and IV were NADPH linked, but nitroreductase I was NADH linked. All enzyme activity was enhanced by addition of flavin mononucleotide and inhibited significantly by dicumarol, p-chloromercuribenzoic acid, o-iodosobenzoic acid, sodium azide, and Cu2+.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
Three forms of alpha-glucosidase, I, II, and III, have been purified from the whole body extract of adult flies of Drosophila melanogaster in yields of 2.1, 5.3, and 6.7%, respectively. The purification procedures involved ammonium sulfate fractionation, Con A-Sepharose 4B affinity chromatography, DEAE-Sepharose CL-6B ion exchange chromatography, Sephacryl S-200 gel filtration, and preparative gel electrophoresis. Each purified enzyme showed a single band on polyacrylamide gel on both protein and enzyme activity staining. The molecular weights of alpha-glucosidases I, II, and III were estimated to be 200,000, 56,000, and 76,000, respectively, by gel filtration. SDS gels indicated that alpha-glucosidases II and III were each composed of a single polypeptide chain, whereas alpha-glucosidase I was composed of two identical subunits. Both alpha-glucosidases II and III hydrolyzed sucrose and p-nitrophenyl-alpha-D-glucoside (PNPG), but alpha-glucosidase I hydrolyzed PNPG to a much lesser extent than sucrose. For sucrose the pH optima of alpha-glucosidases I, II, and III were pH 6.0, 5.0, and 6.0 and the Km values were 13.1, 8.9, and 10 mM, respectively. For PNPG the pH optima of alpha-glucosidases II and III were pH 5.5 and 6.5 and the Km values were 0.77 and 0.21 mM, respectively.  相似文献   

18.
Two molecular species of endoglycoceramidase (designated as endoglycoceramidases I and II) were purified 32,700 and 43,000 times with overall recoveries of 4.8 and 2.9%, respectively, from a culture fluid of the mutant strain M-750 of Rhodococcus sp., cultivated in the absence of inducers (ganglioside). After being stained with Coomassie Brilliant Blue or a silver-staining solution, each purified enzyme showed a single protein band on polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate. The apparent molecular weights, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, were 55,900 for endoglycoceramidase I and 58,900 for endoglycoceramidase II, and their pIs were 5.3 and 4.5, respectively. both were capable of hydrolyzing the glucosylceramide linkage of ganglio-type, lacto-type, and globo-type glycosphingolipids to afford intact oligosaccharides and ceramides. Globo-type glycosphingolipids were strongly resistant to hydrolysis by endoglycoceramidase II in comparison with endoglycoceramidase I. Neither could hydrolyze gala-type glycosphingolipids, cerebrosides, sulfatides, glycoglycerolipids, or sphingomyelins. In addition to these two enzymes, the strain M-750 produced a third minor molecular species of endoglycoceramidase designated as endoglycoceramidase III. It was found capable of specifically hydrolyzing the galactosylceramide linkage of gala-type glycosphingolipids that were not hydrolyzable at all by endoglycoceramidases I or II. The molecular weights of the oligosaccharide and ceramide released from asialo GM1, incubated either in normal H2O or H2(18)O with the enzyme, were compared by fast atom bombardment-mass spectrometry. The result clearly indicated that both endoglycoceramidases I and II hydrolyze the glycosidic linkage between the oligosaccharide and ceramide. Thus, a systematic name of the endoglycoceramidase should be glycosyl-N-acyl-sphingosine 1,1-beta-D-glucanohydrolase.  相似文献   

19.
Bovine articular type II collagen was prepared by limited pepsin digestion, differential salt fractionation and carboxymethylcellulose chromatography. Cyanogen bromide digestion of purified type II collagen alpha chains yielded twelve distinct peptides designated CB1-12. The peptide alpha 1(II)-CB11 was isolated by carboxymethylcellulose chromatography and Sephadex G-75S gel filtration. Automated Edman degradation together with chymotrypsin, thermolysin and trypsin digestion enabled identification of its complete amino acid sequence. Compared with type I and type III collagen, the data show similarity with alpha 1(I)-CB8 and alpha 1(III)-CB6-1-8-10-2 peptides, respectively. The peptide is located within residues 124-402 of the alpha 1(II) collagen chain and with its identification, now extends the known amino acid sequence of bovine type II cartilage collagen to 660 amino acid residues including alpha 1(II)-CB1-2-6-12-11-8-10 (partial). This corresponds to alpha 1(I)-CB0-1-2-4-5-8-3-7 (partial; 1-660) and alpha 1(III)-CB3A-3B-3C-7-6-1-8-10-2-4-5 (partial; 1-660) of bovine alpha 1(I) and alpha 1(III) collagen chains.  相似文献   

20.
Composition analysis of monosaccharides of Sepharose 4B purified NC 92 LPS and the polysaccharides fractions from Sephadex G-50 chromatography was performed by high performance anion exchange chromatography using pulsed amperometric detection. Rhamnose, mannose, galactose and glucose are present in a substantial amount in the purified LPS (Pk I). High molecular weight purified polysaccharides (PS I) obtained after sephadex gel filtration of the purified LPS (Pk I) acid hydrolysate showed an increase in glucose:galactose ratio. This indicates the presence of the peanut root lectin (PRA II) specific sugar in higher proportion on the O-antigen part of the LPS molecule, which may aid in the critical recognition reaction.  相似文献   

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