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1.
Eur J Biochem ; 250(1): 163-7, 1997 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9432005

RESUMO

The specific polysaccharide antigen of Streptococcus pneumoniae serotype 35A was shown, by a combination of one- and two-dimensional NMR methods and chemical analyses, to be a high-molecular-mass polymer composed of D-galactose, D-glucose, mannitol, and phosphate (3:1:1:1). The pentasaccharide repeating unit is polymerized through phosphate diester linkages to give the structure, [formula in text] O-Acetyl substituents are present at positions 5 and 6 of the 3)-beta-D-Galf residue and at position 2 of the 6)-beta-D-Galf residue. The capsular polysaccharides of S. pneumoniae serotypes 20 and 35A both contain the disaccharide unit -->3)-beta-D-Galf-(1-->3)-beta-D-Glcp-(1--> which is the probable structural determinant responsible for the serological cross reactivity of the two polysaccharides.


Assuntos
Cápsulas Bacterianas/imunologia , Polissacarídeos Bacterianos/imunologia , Streptococcus pneumoniae/imunologia , Cápsulas Bacterianas/química , Configuração de Carboidratos , Sequência de Carboidratos , Reações Cruzadas , Dissacarídeos/análise , Dissacarídeos/imunologia , Epitopos/análise , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular , Oligossacarídeos/análise , Oligossacarídeos/imunologia , Polissacarídeos Bacterianos/química , Sorotipagem , Streptococcus pneumoniae/classificação
2.
Carbohydr Res ; 272(2): 231-9, 1995 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-7497480

RESUMO

The O antigen of the lipopolysaccharide of Burkholderia cepacia serotype E (O2) was shown by a combination of methylation analysis, partial hydrolysis, NMR, and mass spectrometric methods to be a high molecular weight polysaccharide composed of two different trisaccharide repeating units in the ratio 2:1. The major trisaccharide component is composed of two alpha-D-mannopyranosyl and one beta-D-galactopyranosyl residues with the structure, [-->2)-alpha-D-Man p-(1-->2)-alpha-D-Man p-(1-->4)-beta-D-Gal p-(1-->]n The minor trisaccharide component is a D-mannan composed of two alpha- and one beta-D-mannopyranosyl residues with the structure, [-->2)-alpha-D-Man p-(1-->2)-alpha-D-Man p-(1-->3)-beta-D-Man p-(1-->]n


Assuntos
Antígenos O/química , Pseudomonas/química , Trissacarídeos/química , Configuração de Carboidratos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular , Estrutura Molecular , Pseudomonas/classificação , Sorotipagem
3.
Carbohydr Res ; 256(2): 303-17, 1994 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-7514497

RESUMO

The O antigen obtained from the lipopolysaccharide of Yersinia ruckeri serotype 01, by mild acid hydrolysis, is composed of a branched tetrasaccharide repeating unit containing 2-acetamidino-2,6-dideoxy-L-galactose (L-FucAm), 2-acetamido-2-deoxy-D-glucose (D-GlcNAc), and 7-acetamido-3,5,7,9-tetradeoxy-5-(4-hydroxybutyramido)-D-glycero-L -galacto- nonulosonic acid (L-Sug). Partial hydrolysis of the O antigen with 0.1 M HClafforded a trisaccharide and a tetrasaccharide having nonulosonic acid at their reducing ends. Cleavage of the O antigen with anhydrous methanolic hydrogen fluoride afforded the methyl glycoside derivatives of a trisaccharide and a tetrasaccharide. 1H and 13C NMR analysis, including 1H-13C heteronuclear multiple bond correlation spectroscopy to locate the N-acyl substituents, together with mass spectrometric analysis of the above oligosaccharides, allowed the structure of the O-specific polysaccharide to be assigned as: [formula: see text].


Assuntos
Lipopolissacarídeos/química , Oligossacarídeos/química , Polissacarídeos Bacterianos/química , Yersinia/química , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Antígenos O , Análise de Sequência , Sorotipagem , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Yersinia/classificação
4.
Biochem Cell Biol ; 71(9-10): 417-20, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7514883

RESUMO

The O-antigenic polysaccharides of the lipopolysaccharides produced by three isolates of Pseudomonas cepacia serogroup A were analysed by composition, methylation, periodate oxidation, and two-dimensional nuclear magnetic resonance methods. They were found to be identical linear unbranched polymers of a repeating trisaccharide unit containing 2-acetamido-2-deoxy-D-galactose and L-rhamnose residues (2:1) and have the structure [-->3)-alpha-D-GalpNAc-(1-->3)-beta-D-GalpNAc-(1-->4)-alpha-L-Rhap -(1-->]n.


Assuntos
Lipopolissacarídeos/química , Polissacarídeos Bacterianos/química , Pseudomonas/imunologia , Configuração de Carboidratos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular , Antígenos O , Oxirredução , Sequências Repetitivas de Ácido Nucleico
5.
Eur J Biochem ; 214(1): 209-14, 1993 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8508793

RESUMO

The capsular antigen of Actinobacillus pleuropneumoniae serotype 11 was characterized by one-dimensional high-field nuclear magnetic resonance methods and chemical analyses, as a teichoic-acid-type polymer composed of a repeating unit with the structure [see text].


Assuntos
Actinobacillus pleuropneumoniae/imunologia , Cápsulas Bacterianas/química , Actinobacillus pleuropneumoniae/química , Cápsulas Bacterianas/isolamento & purificação , Sequência de Carboidratos , Cromatografia em Gel , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular , Polímeros
6.
Eur J Biochem ; 210(1): 119-24, 1992 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1446664

RESUMO

The specific capsular antigen of Actinobacillus pleuropneumoniae serotype 9 was characterized by one-dimensional and two-dimensional high-field nuclear-magnetic-resonance methods, and by chemical analyses, as a teichoic-acid-type polymer of a repeating unit having the structure [formula: see text] The basic polymer structure is identical to capsular antigens of Neisseria meningitidis group H, Escherichia coli K62 (K2ab) and Pasteurella haemolytica serotype T15.


Assuntos
Actinobacillus/imunologia , Antígenos de Bactérias/química , Escherichia coli/imunologia , Mannheimia haemolytica/imunologia , Neisseria meningitidis/imunologia , Reações Cruzadas , Imunodifusão , Espectroscopia de Ressonância Magnética
7.
J Bacteriol ; 174(16): 5324-31, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1379584

RESUMO

The antigenic lipopolysaccharide O polysaccharides of capsular serotypes 9 and 11 were examined by chemical, immunological, and nuclear magnetic resonance methods. Immunodiffusion tests carried out on these O antigens indicated that both contained common epitopes which were also shared by Actinobacillus pleuropneumoniae serotype 1. Chemical analysis and high-field nuclear magnetic resonance spectroscopy showed that the O antigens of serotypes 9 and 11 were high-molecular-weight polymers consisting of a backbone of repeating trisaccharide units composed of alpha-L-rhamnopyranosyl and alpha-D-glucopyranosyl residues (2:1). One of the alpha-L-rhamnose units forms a branch point and is stoichiometrically substituted with terminal 2-acetamido-2-deoxy-beta-D-glucose residues in the serotype 11 O polysaccharide, but only to the extent of 25% in the serotype 9 O polysaccharide. Thus, the serotype 9 O polysaccharide contains two different repeating units: a tetrasaccharide unit with the same structure as that of the serotype 11 O polysaccharide and a trisaccharide unit: [formula: see text] where R = beta-D-GlcpNAc for serotype 1 and 11 O polysaccharides, and R = H (75%) and R = beta-D-GlcpNAc (25%) for serotype 9. The structure of the previously determined serotype 1 O polysaccharide (E. Altman, J.-R. Brisson, and M. B. Perry, Biochem. Cell. Biol. 64:17-25, 1986) is identical to that of the serotype 11 O polysaccharide. We propose a more complete serotyping scheme for A. pleuropneumoniae which includes designation of both the capsular (K) and O antigens.


Assuntos
Actinobacillus pleuropneumoniae/imunologia , Polissacarídeos Bacterianos/análise , Actinobacillus pleuropneumoniae/classificação , Sequência de Carboidratos , Eletroforese em Gel de Poliacrilamida , Epitopos/imunologia , Imunodifusão , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular , Antígenos O , Polissacarídeos Bacterianos/imunologia , Sorotipagem
8.
J Bacteriol ; 174(7): 2172-7, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1551839

RESUMO

Proteus mirabilis 2573 (ATCC 49565) produces an acidic capsular polysaccharide which was shown from glycose analysis, carboxyl reduction, methylation, periodate oxidation, and the application of one dimensional and two-dimensional high-resolution nuclear magnetic resonance techniques to be a high-molecular-weight polymer of branched trisaccharide units composed of 2-acetamido-2-deoxy-D-glucose (N-acetyl-D-glucosamine), 2-acetamido-2,6-dideoxy-L-galactose (N-acetyl-L-fucosamine), and D-glucuronic acid, having the structure: [formula: see text] P. mirabilis 2573 also produces an O:6 serotype lipopolysaccharide in which the O-chain component has the same structure as the homologous capsular polysaccharide. This is the first report of a defined capsular polysaccharide in this bacterial genus.


Assuntos
Polissacarídeos Bacterianos/química , Proteus mirabilis/ultraestrutura , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular
9.
Carbohydr Res ; 220: 185-93, 1991 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-1811856

RESUMO

The capsular polysaccharide of A. pleuropneumoniae serotype 10 was found to be composed of a linear disaccharide repeating unit. By use of methylation analysis, partial hydrolysis, g.l.c.--and f.a.b.- m.s., and 1D and 2D n.m.r. studies, the polysaccharide was determined to be a polymer of a repeating disaccharide unit composed of D-mannose and 3-deoxy-D-manno-octulosonic acid (Kdo) having the structure: [formula; see text]


Assuntos
Actinobacillus pleuropneumoniae/química , Cápsulas Bacterianas/química , Polissacarídeos Bacterianos/química , Sequência de Carboidratos , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular , Polissacarídeos Bacterianos/isolamento & purificação , Sorotipagem , Soluções/química
10.
Carbohydr Res ; 212: 219-27, 1991 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-1959118

RESUMO

The capsular polysaccharide of A. pleuropneumoniae is composed of 2-acetamido-2-deoxy-D-glucose (3 parts) and phosphate (1 part). The arrangement of these components in the repeating unit was determined by dephosphorylation, methylation, g.l.c.-m.x., and 1D and 2D n.m.r. spectroscopic methods. The polysaccharide was found to be a high molecular weight polymer of repeating trisaccharide units, joined through phosphate diester linkages, having the structure, (formula: see text).


Assuntos
Actinobacillus pleuropneumoniae/química , Cápsulas Bacterianas/química , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Estrutura Molecular , Fosforilação
11.
Carbohydr Res ; 209: 225-38, 1991 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1709819

RESUMO

The structure of the O-antigen polysaccharide of A. pleuropneumoniae serotype 7 was investigated by methylation analysis, partial acid hydrolysis, periodate oxidation, and 1H- and 13C-n.m.r. spectroscopy. The polysaccharide repeating-unit consists of a branched tetrasaccharide having the following structure. [formula: see text]


Assuntos
Actinobacillus/análise , Antígenos de Bactérias/química , Lipopolissacarídeos/química , Actinobacillus/classificação , Actinobacillus/imunologia , Configuração de Carboidratos , Sequência de Carboidratos , Lipopolissacarídeos/imunologia , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Estrutura Molecular , Antígenos O , Sorotipagem
12.
Carbohydr Res ; 209: 211-23, 1991 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-2036652

RESUMO

The structure of the capsular polysaccharide antigen of A. pleuropneumoniae serotype 7 was determined using 1D- and 2D-n.m.r. methods. Dephosphorylation, methylation, and g.l.c.-mass spectrometry methods were used to confirm the analysis. The type-7 specific polysaccharide was a high-molecular-weight teichoic acid-type polymer of D-galactose, glycerol, and phosphate (2:1:1), composed of glycosylglycerol repeating units joined through monophosphate diester linkages and with the structure: [formula: see text]


Assuntos
Actinobacillus/análise , Polissacarídeos Bacterianos/química , Actinobacillus/classificação , Actinobacillus/imunologia , Antígenos de Bactérias/química , Cápsulas Bacterianas , Configuração de Carboidratos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Estrutura Molecular , Polissacarídeos Bacterianos/imunologia , Sorotipagem
13.
Carbohydr Res ; 205: 347-59, 1990 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-2276143

RESUMO

The structure of the capsular antigen of E. coli K49 and the oligosaccharides derived from it by partial acid hydrolysis were studied by 1D- and 2D-n.m.r. spectroscopy, g.l.c.-c.i.-mass spectrometry, and methylation analysis. The K49 polysaccharide consists of the repeating unit----4)-beta-D-GlcpA-(1----6)-beta-D-Galp-(1----6)-beta-D-Glcp- (1----3)-beta - D-GalpNAc-(1----. The glucuronic acid residues are substituted, in the apparent molar ratio of 4:1, with L-threonine and L-serine linked amidically to the carboxyl group.


Assuntos
Polissacarídeos Bacterianos/química , Antígenos de Bactérias/química , Cápsulas Bacterianas , Sequência de Carboidratos , Escherichia coli/análise , Escherichia coli/imunologia , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Polissacarídeos Bacterianos/imunologia
14.
Carbohydr Res ; 200: 457-68, 1990 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-2199040

RESUMO

The structure of the capsular antigen of E. coli K26 has been found by a combination of chemical and spectroscopic techniques to be of the "5 + 1" type shown. An important step was the simultaneous separation and identification of a mixture of neutral and acidic oligosaccharides by g.l.c.-c.i.-m.s. [formula: see text]


Assuntos
Antígenos de Bactérias , Escherichia coli/imunologia , Sequência de Carboidratos , Fenômenos Químicos , Química , Reações Cruzadas , Hidrólise , Metilação , Dados de Sequência Molecular
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