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1.
A specific acidic polysaccharide has been isolated from the Shigella boydii type 14 antigenic lipopolysaccharide after mild hydrolysis followed by chromatography on Sephadex G-50. The polysaccharide consists of the D-glucuronic acid, 2-acetamido-2-deoxy-D-glucose and D-galactose residues in the ratio 1:1:3. From the results of methylation analysis and partial acid hydrolysis, the structure of the repeating unit of the specific polysaccharide was deduced as follows: (-6DGalp alpha 1-4DGlcAp beta 1-6DGalp beta 1-4DGalp beta 1-4DGlcNAcp beta 1-)n. The 13C NMR spectra of native and carboxyl-reduced polysaccharides, as well as of oligosaccharides produced by partial acid hydrolysis fully confirmed the proposed structure. The approach was suggested to determine the type of substitution of uronic acid moieties in polysaccharide chain by use of chromato-mass-spectrometry of acetylated methyl esters of partially methylated aldonic acids. Serological characteristics of Sh. boydii LPS type 14 and its modified derivatives are discussed.  相似文献   

2.
The specific polysaccharide was obtained from the lipopolysaccharide of Shigella newcastle by mild acid hydrolysis and further purified by permeation chromatography on Sephadex G-50. It was found to consist of L-rhamnose, 2-acetamido-2-deoxy-D-galactose, D-galacturonic acid residues and O-acetyl groups in the molar ratios of 2:1:1:1. On the basis of 1H and 13C nuclear magnetic resonance spectroscopy, methylation analysis, partial acid hydrolysis, Smith degradation, and chromium trioxide oxidation, the following structure can be assigned to the repeating oligosaccharide unit of the polysaccharide:-4)DGalA(beta 1-3)DGalNAc-(beta 1-2)LAc3Rha(alpha 1-2)LRha(alpha 1-, where GalA = galacturonic acid. GalNAc = N-acetylgalactosamine, Ac3Rha = 3-O-acetylrhamnose. The structural and immunochemical data presented prove that Sh. newcastle lipopolysaccharide belongs to a 'non-classical' type of somatic antigens with acidic O-specific polysaccharide chains.  相似文献   

3.
The phenol-phase soluble antigenic lipopolysaccharide was isolated from Brucella melitensis, strain 565, by the routine phenol/water procedure followed by chromatography on Sepharose 4B. After mild acid hydrolysis and chromatography on Sephadex G-50, the lipopolysaccharide yielded a linear O-specific polysaccharide built up from 1,2-linked 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl units. The structure of the polysaccharide was deduced mainly from the nuclear magnetic resonance and methylation analyses. The phenol-soluble lipopolysaccharide, isolated from commercial vaccine strain B. abortus 19-BA, on mild hydrolysis afforded material, 13C and 1H-NMR spectra of which were identical to those of the O-specific polysaccharide from B. melitensis 565.  相似文献   

4.
A specific acidic polysaccharide was isolated from Sh. boydii type 8 antigenic lipopolysaccharide after mild hydrolysis followed by chromatography on Sephadex G-50. The polysaccharide consists of D-glucuronic acid, D-galacturonic acid, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-galactose and 2-amino-1,3-propanediol residues in 1:1:1:1:1 ratio. From the results of methylation analysis, partial acid hydrolysis and Smith degradation, the structure of the repeating unit of the specific polysaccharide was deduced as: (Formula: see text). The 13C NMR spectra of native, O-deacetylated and carboxyl-reduced polysaccharides, as well as the spectrum of oligosaccharide produced by Smith degradation were interpreted. The 13C NMR data fully confirmed the structure of the polysaccharide repeating unit.  相似文献   

5.
The structure of the O-specific polysaccharide of the somatic antigen (lipopolysaccharide) of Shigella boydii, type 12, was established by 1H- and 13C-NMR, methylation analysis and partial acid hydrolysis methods. The polysaccharide consists of pentasaccharide repeating units of the following structure: (formula; see text) The amount of O-acetyl groups was far less than stoichiometric, only about 2 for 3-4 repeating units. Nevertheless, the results of serological studies revealed 3-O-acetyl-alpha-L-rhamnose residue to be the major immunodominant group. In spite of the presence of similar trisaccharide fragments, the lipopolysaccharide and polysaccharide from Shigella boydii type 12 gave no crossreaction with lipopolysaccharide and polysaccharide from Escherichia coli 07. The possible reasons of the absence of serological relatedness between the Sh. boydii, type 12, and E. coli 07 cells were discussed.  相似文献   

6.
On mild acid degradation of the Shigella boydii, type 11 lipopolysaccharide, the corresponding O-specific polysaccharide composed of D-glucuronic acid, 2-acetylamino-2-deoxy-D-glucose, D-ribose and L-rhamnose residues in the ratio 1:1:1:3 was obtained. Methylation, partial acid hydrolysis and 13C-NMR spectral data for the polysaccharide led to the structure of the oligosaccharide repeating unit as a branched hexasaccharide: [formula: see text]. Numerous O-acetyl groups attached non-stoichiometrically to the residues of D-glucuronic acid, L-rhamnose and 2-acetylamino-2-deoxy-D-glucose were located with the use of 13C-NMR spectroscopy.  相似文献   

7.
The chemical structure of the polysaccharide moiety of the lipopolysaccharide Rhodopseudomonas sphaeroides ATCC 17023 was established. Mild acetic acid hydrolysis of isolated lipopolysaccharide, followed by preparative high-voltage paper electrophoresis afforded three oligosaccharides. They were characterized by chemical and physicochemical studies to be: GlcA(alpha 1----4)dOclA8P, Thr(6') GlcA(alpha 1----4)GlcA and GlcA(alpha 1----4)dOclA, where GlcA is D-glucuronic acid and dOc1A is 3-deoxy-D-manno-octulosonic acid. Carboxyl-reduction of the lipopolysaccharide followed by acid hydrolysis gave a trisaccharide: GlcA(alpha 1----4)Glc(alpha 1----4)Glc, showing the presence of three residues of glucuronic acids in the O-specific chain and indicating that only two of them are reducible by NaBH4. The linkage between the polysaccharide and lipid A was shown to be through a single 1,4-linked residue of dOc1A attached by a 2,6'-linkage to the lipid A moiety.  相似文献   

8.
Lipopolysaccharides were isolated from the phenol layer on aqueous phenol extraction of cells of Pseudomonas aeruginosa O11 (Lányi classification), strains 170021 and 170040. On mild acid degradation of the lipopolysaccharides, with the subsequent gel-filtration on Sephadex G-50, neutral O-specific polysaccharides made up of 6-deoxysugars alone were obtained. Two 2-acetamido-2,6-dideoxy-L-galactose (LFucNAc), 2-acetamido-2,6-dideoxy-D-glucose (DQuiNAc) and L-rhamnose (LRha) residues were found to be the components of the strain 170021 polysaccharide repeating units; those of strain 170040 contained the same monosaccharides, but, instead of 2-acetamido-2,6-dideoxy-D-glucose residue, that of 2-acetamido-2,6-dideoxy-D-galactose (DFucNAc) was present. On the basis of the 13C nuclear magnetic resonance data, methylation analysis and three successive Smith degradations the following structures were determined for the polysaccharide repeating units: strain 170021----2) LRha(alpha 1----3)LFucNAc(alpha 1----3)LFucNAc(alpha 1----3)DQuiNAc(beta 1----; strain 170040,----2)LRha(alpha 1----3)LFucNAc-(alpha 1----3)LFucNAc(alpha 1----3)DFucNAc(beta 1----; differing from one another by configuration of C-4 of 2-acetamido-2,6-dideoxy-D-hexopyranose only.  相似文献   

9.
Structure of the O-antigen of Francisella tularensis strain 15.   总被引:2,自引:0,他引:2  
The O-specific polysaccharide, obtained by mild acid degradation of the lipopolysaccharide of Francisella tularensis strain 15, contained 2-acetamido-2,6-dideoxy-D-glucose (D-QuiNAc), 4,6-dideoxy-4-formamido-D-glucose (D-Qui4NFm), and 2-acetamido-2-deoxy-D-galacturonamide (D-GalNAcAN) in the ratios 1:1:2. Tri- and tetra-saccharide fragments were obtained on treatment of the polysaccharide with anhydrous hydrogen fluoride and partial hydrolysis with 0.1 M hydrochloric acid, respectively. On the basis of 1H- and 13C-n.m.r. spectroscopy of the polysaccharide and the saccharides, it was concluded that the O-antigen had the structure: ----4)-alpha-D-GalpNAcAN-(1----4)-alpha-D-GalpNAcAN-(1----3) -beta-D-QuipNAc-(1----2)-beta-D-Quip4NFm-(1----. This O-antigen is related in structure to those of Pseudomonas aeruginosa O6, immunotype 1, and IID 1008, and Shigella dysenteriae type 7.  相似文献   

10.
The rfb gene, involved in the synthesis of the O-specific polysaccharide (a mannose homopolymer) of Escherichia coli O9 lipopolysaccharide (LPS), was cloned in E. coli K-12 strains. The O9-specific polysaccharide covalently linked to the R core of K-12 was extracted from the K-12 strains harboring the O9 rfb gene. All the other genes required for the synthesis of rfe-dependent LPS are therefore considered to be present in the K-12 strains. It was found that bacteria harboring some clones with deletions of the ca. 20-kilobase-pair (kbp) BglII-StuI fragment no longer synthesized the O9-specific polysaccharide. However, bacteria harboring clones del 21, del 22, and del 25, which carry deletions of the 10-kbp PstI-StuI fragment, synthesized an O-specific polysaccharide antigenically distinct from E. coli O9 LPS. Although this new O-specific polysaccharide consisted solely of mannose and the mannose residues were combined only through alpha-1,2 linkage, it was still composed of a repeating oligosaccharide unit, possibly a trisaccharide unit,----2)alpha Man-(1----2)alpha Man-(1----2)alpha Man-(1----. It is therefore likely that this new O-specific polysaccharide was derived from a part of the O9-specific polysaccharide----3)alpha Man-(1----3)alpha Man-(1----2)alpha Man-(1----2)alpha Man-(1----2)alpha Man-(1----and that the deleted part of the clones was responsible for the synthesis of alpha-1,3 linkages of the O9-specific polysaccharide.  相似文献   

11.
The O-specific polysaccharide, obtained on mild acid degradation of lipopolysaccharide of Pseudomonas aeruginosa O13 (Lányi classification), is built up of trisaccharide repeating units involving 2-acetamidino-2,6-dideoxy-D-glucose (N-acetyl-D-quinovosamine, D-QuiNAc), 2-acetamidino-2,6-dideoxy-L-galactose (L-fucosacetamidine, L-FucAm), and a new sialic-acid-like sugar, 5,7-diacetamido-3,5,7,9-tetradeoxy-D-glycero-L-galacto-nonuloso n ic acid (Sug), and thus contains simultaneously both acidic and basic functions. Cleavage of the polysaccharide with hydrogen fluoride in methanol revealed the high stability of the glycosidic linkage of the ulosonic acid and afforded methyl glycosides of a disaccharide and a trisaccharide. The structures of the new ulosonic acid and acetamidino group were established by analysing the oligosaccharide fragments by 1H, 13C nuclear magnetic resonance spectrometry, as well as on the basis of their chemical conversions: alkaline hydrolysis of the acetamidino group into acetamido group, reductive deamination with lithium borohydride into the ethylamino group and acetylation with acetic anhydride in pyridine accompanied by intramolecular acylation of the acetamidino function by the ulosonic acid to form a six-membered lactam ring. Identification of the oligosaccharide fragments and comparative analysis of the 13C nuclear magnetic resonance spectra of the oligosaccharides and polysaccharide revealed the following structure of the repeating unit: ----3)D-QuiNAcp(alpha 1----3)Sugp(alpha 2----3)L-FucAmp(alpha 1----.  相似文献   

12.
The lipopolysaccharide from Pseudomonas aeruginosa O12 (Lányi classification) gave on mild acid hydrolysis an O-specific polysaccharide built of D-ribose and N-acetyl-D-galactosamine. The disaccharide structure----4)-alpha-GalNAcp-(1----2)-beta-Ribf-(1----for the repeating unit of the polysaccharide was established by nondestructive way involving full interpretation of its 1H- and 13C-NMR-spectra, using homonuclear and selective heteronuclear 13C[1H] double resonances.  相似文献   

13.
The O-specific polysaccharide obtained from the lipopolysaccharide of Shigella dysenteriae type 1 (Shigella shiga) by mild acid hydrolysis followed by fractionation on Sephadex G-50 was found to be identical to that desribed by Morgan's group and was composed of L-rhamnose, D-galactose and N-acetyl-D-glycosamine in a ratio 2:1:1. On the basis of methylation analysis data the polysaccharide was proved to be a linear chain of monosaccharide residues in pyranose forms substituted at position 3, except for that of galactose substituted at position 2. Selective cleavage, based on the N-deacetylation reaction of the polymer, together with determination of linkage configurations by chromic anhydride oxidation showed that the O-specific polysaccharide is built up of repeating tetrasaccharide units whose proposed structure is given below -3)-alpha-L-Rhap (1-3)-alpha-L-Rhap(1-2)-alpha-D-Galp(1-3)-alphapD-GlcNAcp(1- where RHAP = rhamnopyranose, Galp = galactopyranose, and GlcNAcp = N-acetyl-glucosamine. The present findings confirmed the considerations of Heidelberger on the substitution patterns of L-rhamnose and D-galactose residues from the results of serological studies.  相似文献   

14.
On mild acid degradation of a lipopolysaccharide from Pseudomonas cepacia strain IMV 4137, a serologically active O-specific polysaccharide was obtained and shown to contain L-rhamnose and D-galactose. According to 1H- and 13C-NMR data as well as methylation analysis, the polysaccharide is made up of disaccharide repeating units of the following structure:----2)-alpha-L-Rhap-(1----4)-alpha-D-Galp-(1----.  相似文献   

15.
Acid hydrolysis of the antigenic lipopolysaccharide from Shigella boydii type 7 afforded a specific polysaccharide composed of 2-acetamido-2-deoxy-D-glucose, D-glucose, D-galactose, 5-acetamido-3,5,7,9-tetradeoxy-7-[(3R)-3-hydroxybutyramido]-L- glycero-L-manno-nonulosonic acid (NonN2A) and acetic acid residues in the 1:1:2:1:1 ratio. From the results of methylation analysis, hydrogen fluoride solvolysis and Smith degradation, the structure of the repeating unit of the specific polysaccharide was dedused as: -2) Galf (beta 1-3)GlcNAcp (alpha 1-8)NonN2A (beta 2-6) Galp (alpha 1-6) Glcp (alpha 1-4 increases Ac. The 13C NMR spectrum of the polysaccharide was interpreted, and the spectral data fully confirmed the structure of the polysaccharide repeating unit.  相似文献   

16.
Lipid A and polysaccharide moieties obtained by mild acid hydrolysis of the lipopolysaccharides from Vibrio cholerae 569 B (Inaba) and Vibrio el-tor (Inaba) were characterized. Heterogeneity of lipid A fractions was indicated by t.l.c. and by gel filtration of the de-O-acylated products from mild alkaline methanolysis of the lipids. Presumably lipid A contains a glucosamine backbone, and the fatty acids are probably bound to the hydroxyl and amino groups of glucosamine residues. Approximately equal amounts of fatty acids C16:0, C18:1 and 3-hydroxylauric acid were involved in ester linkages, but 3-hydroxymyristic acid was the only amide-linked fatty acid. Sephadex chromatography of the polysaccharide moiety showed the presence of a high-molecular-weight heptose-free fraction and a low-molecular-weight heptose-containing fraction. Haemagglutination-inhibition assays of these fractions showed the heptose-free fraction to be an O-specific side-chain polysaccharide, whereas the heptose-containing fraction was the core polysaccharide region of the lipopolysaccharides. Identical results were obtained for both organisms.  相似文献   

17.
The specific polysaccharide was released from Shigella dysenteriae type 5 lipopolysaccharide by mild acidic hydrolysis and then purified by gel chromatography on Sephadex G-50. The polysaccharide was built up of residues of D-mannose, 2-acetamido-2-deoxy-D-glucose, 3-0-(D-1-carboxyethyl)-L-rhamnose (rhamnolactylic acid) and 0-acetyl groups in a ratio 2:1:1:1. On the basis of radiospectroscopy, methylation analysis, Smith degradation, and chromium trioxide oxidation, the repeating oligosaccharide unit of the polysaccharide can be assigned the following structure: (formula: see text) where GlcNAc is 2-acetamido-2-deoxy-D-glucopyranose, Manp is mannopyranose, RhaLcA is rhammolacytic acid and Ac is an acetyl group. The serological properties of Sh. dysenteriae somatic antigens are discussed in relation to the chemical structures of their specific polysaccharides.  相似文献   

18.
The structure of polysaccharide prepared by lysozyme digestion from the cell wall of Propionibacterium acnes strain C7 was examined. The polysaccharide fraction was composed of glucose, galactose, mannose, galactosamine, and diaminomannuronic acid in a molar ratio of 1:1:0.3:1:2. By Smith degradation of the polysaccharide, diaminouronic acid-containing fractions were obtained, and the configuration of diaminouronic acid was identified as 2,3-diacetamido-2,3-dideoxymannuronic acid [Man(NAc)2A] by means of 1H-NMR and 13C-NMR spectroscopic analyses. The results of analyses involving methylation and partial acid hydrolysis led to the conclusion that the polysaccharide has the repeating unit----6)Gal(alpha 1----4)Man(NAc)2A(beta 1----6)Glc(alpha 1----4)Man(NAc)2A (beta 1----3)GalNAc(beta 1--. In addition, a portion of the galactose residues were substituted at C-4 by alpha 1----2 linked mannotriose.  相似文献   

19.
alpha-L-Fucosidase was purified from human liver to apparent homogeneity and subjected to exhaustive digestion with Pronase. The resulting glycopeptides were isolated by gel filtration on Sephadex G-50 and further fractionated by Bio-Gel P-4 chromatography. Five glycopeptide fractions were obtained. The structures of the carbohydrate portions of all glycopeptide components were fully characterized by a combination of 500-MHz 1H NMR spectroscopy and carbohydrate composition analysis. Fraction I contained disialyl diantennary glycopeptides of the N-acetyllactosamine type. Fractions II and III contained predominantly mono(sialyl-N-acetyllactosaminyl) diantennary glycopeptides with the NeuAc alpha(2----6)Gal beta(1----4)GlcNAc beta(1----2) branch attached to alpha(1----3)-linked Man in II and to alpha(1----6)-linked Man in III. The N-acetyllactosamine-type glycopeptides in fractions I to III have a small portion (10-15%) of their Asn-linked GlcNAc residues substituted by additional alpha(1----6)-linked Fuc. Also, a minor portion of the NeuAc residues appeared to be attached to Gal in alpha(2----3) rather than alpha(2----6) linkage. Fraction IV contained a mixture of larger-size oligomannoside-type glycopeptides with a variable number (6 to 9) of Man residues. Smaller-size oligomannoside-type glycopeptides were found in fraction V, containing 3 or 5 Man residues; a small portion (10%) of the Man3GlcNAc2Asn component appeared to contain in addition a Fuc residue in alpha(1----6) linkage to the Asn-bound GlcNAc. The overall ratio of oligomannoside-type to N-acetyllactosamine-type carbohydrate structures was found to be 5:4. This article is the first account of the complete characterization of the oligomannoside-type structures in alpha-L-fucosidase; furthermore, the occurrence in alpha-L-fucosidase of mono(sialyl-N-acetyllactosaminyl) structures, Fuc-containing oligosaccharides, and NeuAc alpha(2----3) linked to Gal are reported for the first time.  相似文献   

20.
On mild acid degradation of the Pseudomonas cepacia strain IMV 4176 lipopolysaccharide, two polysaccharides were obtained, one of which is a homopolymer of N-acetyl-D-galactosamine and the other is composed of equal amounts of N-acetyl-D-galactosamine and D-ribose. Partial hydrolysis with aqueous oxalic acid caused depolymerization of the heteropolysaccharide, and the homopolysaccharide was isolated in the individual state. On the basis of methylation and 13C NMR analysis, it was concluded that both polysaccharides are built up of disaccharide repeating units having the following structures: ----4)-alpha-D-GalpNAc-(1----4)-beta-D-GalpNAc-(1---- and ----4)-alpha-D-GalpNAc-(1----2)-beta-D-Ribf-(1----. The heteropolysaccharide from P. cepacia strain 4176 is identical by the structure of the repeating unit to the O-specific polysaccharide of P. cepacia strain IMV 4202 (serotype 3), Pseudomonas aeruginosa O12 and Serratia marcescens O14.  相似文献   

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