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1.
Structural studies were carried out on the O-polysaccharide fraction obtained by mild acid treatment of the lipopolysaccharide from Pseudomonas aeruginosa IID 1009 (ATCC 27585). The O-polysaccharide was composed of L-rhamnose, N-acetyl-D-quinovosamine, and N-acetyl-L-galactosaminuronic acid in a molar ratio of 1:1:1. The results from analysis of fragments obtained by hydrogen fluoride hydrolysis of O-polysaccharide, together with data on methylation analysis and nuclear magnetic resonance spectroscopic analysis, led to the most likely structure of the repeating units of the polymer chain ----4)L-GalNAcA(alpha 1----3)D-QuiNAc(alpha 1----3)L-Rha(alpha 1----, in which about 70% of the rhamnose residues were O-acetylated at C-2. This structure coincides with that of the repeating unit of Lanyi 02 a,b polysaccharides.  相似文献   

2.
Structural studies were carried out on the O-polysaccharide fraction obtained from the lipopolysaccharide of Pseudomonas aeruginosa IID 1008 (ATCC 27584). The O-polysaccharide comprises L-rhamnose, N-acetyl-D-quinovosamine, N-acetyl-D-galactosaminuronic acid, and N-formyl-D-galactosaminuronic acid. The characterization of oligosaccharide fragments resulting from acid hydrolysis, Smith degradation and alkaline degradation of the O-polysaccharide, together with 1H-NMR and 13C-NMR spectroscopic data of the polysaccharide, led to the following structure for the repeating units: ----3)Rha(alpha 1----4)GalNAcA(alpha 1----4 GalNFoA(alpha 1----3)QuiNAc(alpha 1----. Almost all of the carboxyl groups of the N-acetylgalactosaminuronic acid residues and about half of the same groups of the N-formylgalactosaminuronic acid residues were in an amide form.  相似文献   

3.
Structural studies were carried out on the O-polysaccharide fraction obtained from the lipopolysaccharide of Pseudomonas aeruginosa IID 1012, the standard strain of Homma serogroup K, by mild acid treatment. The O-polysaccharide was composed of L-rhamnose, N-acetyl-D-quinovosamine, and N-acetyl-D-galactosaminuronic acid. The results from analysis of fragments obtained by acid hydrolysis and Smith degradation of the O-polysaccharide, together with data on methylation analysis and nuclear magnetic resonance spectroscopic measurement of the polysaccharide, led to the most likely structure of the repeating units of the polymer chain, ----4)D-GalNAcA(alpha 1----3)D-QuiNAc(beta 1----2)L-Rha(alpha 1----3)L-Rha(alpha 1----, in which about 20% of the N-acetylgalactosaminuronic acid residues were in an amide form and about 75% of the same residues were O-acetylated at C-3.  相似文献   

4.
Structural studies were carried out on a rhamnose-rich polysaccharide isolated from the O-polysaccharide fraction of lipopolysaccharide in Pseudomonas aeruginosa IID 1008 (ATCC 27584) after destruction of the major O-specific chain by alkaline treatment. The isolated polysaccharide contained rhamnose, 3-O-methyl-6-deoxyhexose, glucose, xylose, alanine, galactosamine and phosphorus in a molar ratio of 67:6.9:4.3:2.1:1.1:1.0:4.1. Data from analysis involving Smith degradation, methylation, 1H-NMR spectroscopy and optical rotation measurement showed that the polysaccharide was built up of three moieties, a rhamnan chain composed of about 70 D-rhamnose residues, the core chain and an oligosaccharide chain comprising 3-O-methyl-6-deoxyhexose, xylose, rhamnose and probably glucose. The repeating unit of the rhamnan chain was indicated to have the following structure:----3)D-Rha(alpha 1----3)D-Rha(alpha 1----2)D-Rha(alpha 1----. This structure is identical with that proposed previously for the repeating unit of the side chain of lipopolysaccharide from plant pathogenic bacteria Pseudomonas syringae pv. morsprunorum C28 [Smith, A.R.W., Zamze, S.E., Munro, S.M., Carter, K. J. and Hignett, R.C. (1985) Eur. J. Biochem. 149, 73-78].  相似文献   

5.
Taylorella asinigenitalis sp. nov is a nonpathogenic gram-negative bacterium recently isolated from the genital tract of male donkeys. The bacterium is phenotypically indistinguishable from Taylorella equigenitalis, a pathogen that is the cause of contagious equine metritis, a highly communicable venereal disease of horses. The structural analysis of the lipopolysaccharide produced by T. asinigenitalis sp. nov (ATCC 700933) demonstrated that its O-polysaccharide (O-PS) component is a linear unbranched polymer of repeating disaccharide units composed of 1,3-linked pyranosyl residues of 2,4-diacetamido-2,4-dideoxy-beta-D-quinovose (bacillosamine) and 2-acetamidino-2-deoxy-beta-D-glucuronic acid, and has the structure [-->3)-beta-D-QuipNAc4NAc-(1-->3)-beta-D-GlcpNAmA-(1-->]n. The chemical structure and serological characteristics of the T. asinigenitalis O-PS are distinct from those of the O-PS of the T. equigenitalis type strain, thus providing a cell-surface target macromolecule that can be used to distinguish pathogenic from nonpathogenic Taylorella sp. clinical isolates.  相似文献   

6.
The O-polysaccharide from Vibrio cholerae O6 was isolated from the LPS by mild-acid hydrolysis and has been investigated by sugar and methylation analysis and NMR spectroscopy. The polysaccharide was also depolymerized with aqueous hydrofluoric acid to give the repeating unit and multiples thereof. The O-polysaccharide had the following tetrasaccharide repeating unit. Two O-acetyl groups are present, one of them making the GlcNAc residue fully substituted and the steric crowding considerable at the branching residue.  相似文献   

7.
Lipopolysaccharide (LPS) from smooth strains of Pseudomonas aeruginosa 503, PAZ1, PAO1715, PAO1716, and Z61 was fractionated by gel filtration chromatography. LPS samples from the first four strains, all PAO1 derivatives, separated into three major size populations, whereas LPS from strain Z61, a Pac K799/WT mutant strain, separated into two size populations. When column fractions were applied to sodium dodecyl sulfate-polyacrylamide gels in their order of elution, molecules of decreasing size were resolved, and the ladder of molecules with different-length O antigens formed a diagonal across the gel. The LPS from the PAO1 derivatives contained two distinct sets of bands, distinguished on the gels as two sets of diagonals. The set of bands with the faster mobility, the B bands, was found in column fractions comprising the three major amino sugar-containing peaks. In the sample from strain 503, a fourth minor peak which contained B bands was resolved. The slower-moving set of bands, the A bands, were recovered in a minor peak. LPS from strain Z61 contained only one set of bands, with the higher-molecular-weight molecules eluting from the column in a volume similar to that of the B bands of the PAO1 strains. Analysis of the fractions of LPS from all strains indicated that less than 8% of the LPS molecules had a long, attached O antigen. Analysis of the peak that contained mainly A bands indicated a lack of reactive amino sugar and phosphate, although heptose and 2-keto-3-deoxyoctulosonic acid were detected. Reaction of isolated fractions with monoclonal antibody specific for the PAO1 O-antigen side chain indicated that only the B bands from the PAO1 strains were antigenically reactive. The bands from strain Z61 showed no reactivity. The data suggest that the A and B bands from the PAO1 strains are antigenically distinct. We propose that PAO1 strains synthesize two types of molecules that are antigenically different.  相似文献   

8.
Structural studies have been carried out on the O-specific fraction from the lipopolysaccharide of Pseudomonas aeruginosa NCTC 8505, Habs serotype 03. The O-specific polysaccharide has a tetrasaccharide repeating-unit containing residues of L-rhamnose (Rha), 2-acetamido-2-deoxy-D-glucose (GlcNAc), 2-acetamido-2-deoxy-L-galacturonic acid (GalNAcA), and 2,4-diacetamido-2,4,6-trideoxy-D-glucose (BacNAc2). The following structure has been assigned to the repeating-unit: leads to 3)Rhap(beta 1 leads to 6)GlcpNAc(alpha 1 leads to 4)GalpNAcA(alpha 1 leads to 3)BacpNAc2(alpha 1 leads to. The parent lipopolysaccharide is a mixture of S, R, and SR species, and its high phosphorus content is partly due to the presence of triphosphate residues, as found for other lipopolysaccharides from P. aeruginosa. In addition to phosphorus, heptose, a 3-deoxyoctulosonic acid, and amide-bound alanine, the core oligosaccharide contains glucose, rhamnose, and galactosamine (molar proportions 3:1:1). The rhamnose and part of the glucose are present as unsubstituted pyranoside residues: other glucose residues are 6-substituted.  相似文献   

9.
The structure of the lipopolysaccharide (LPS) of Pseudomonas aeruginosa immunotype 1 was studied after mild acid and strong alkaline degradations by MS and NMR spectroscopy. Three types of LPS molecules were found, including those with an unsubstituted glycoform 1 core (A) or an isomeric glycoform 2 core substituted with one O-polysaccharide repeating unit (B) or with a long-chain O-polysaccharide. Therefore, of two core glycoforms, only glycoform 2 accepts the O-polysaccharide. In the structures A and B, Kdo, Hep, Hep7Cm, GalNAcAN3Ac, GalNFoAN, QuiNAc, GalNAla represent 3-deoxy-d-manno-octulosonic acid, l-glycero-d-manno-heptose, 7-O-carbamoyl-l-glycero-d-manno-heptose, 2-acetamido-3-O-acetyl-2-deoxygalacturonamide, 2-formamido-2-deoxygalacturonamide, 2-acetamido-2,6-dideoxyglucose and 2-(l-alanylamino)-2-deoxygalactose, respectively; all sugars are in the pyranose form and have the d configuration unless otherwise stated. One or more phosphorylation sites may be occupied by diphosphate groups. In a minority of the LPS molecules, an O-acetyl group is present in the outer core region at unknown position. The site and the configuration of the linkage between the O-polysaccharide and the core and the structure of the O-polysaccharide repeating unit were defined in P. aeruginosa immunotype 1. The QuiNAc residue linked to the Rha residue of the core was found to have the beta configuration, whereas in the interior repeating units of the O-polysaccharide this residue is in the alpha-configuration. The data obtained are in accordance with the initiation of biosynthesis of the O-polysaccharide of P. aeruginosa O6, which is closely related to immunotype 1, by transfer of d-QuiNAc-1-P to undecaprenyl phosphate followed by synthesis of the repeating O-antigen tetrasaccharide.  相似文献   

10.
The O-polysaccharide was obtained by a mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O29. Structural studies were performed using sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including two-dimensional 1H, 1H COSY, TOCSY, ROESY, H-detected 1H, 13C HSQC and HMBC experiments. On the basis of the data obtained, the following structure of the branched tetrasaccharide repeating unit of the O-polysaccharide was established: [structure: see text].  相似文献   

11.
An O-polysaccharide and oligosaccharides were isolated by GPC following mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O28. The O-polysaccharide was studied by sugar and methylation analyses, 1H and 13C NMR spectroscopy, including 2D ROESY and H-detected 1H,13C HSQC and HMBC experiments, and the following structure of the branched pentasaccharide repeating unit was established:This structure was confirmed by ESI MS of the isolated tridecasaccharide consisting of the lipopolysaccharide core and one O-polysaccharide repeat. The ESI mass spectrum also enabled inferring the composition of the core oligosaccharide.  相似文献   

12.
An O-polysaccharide (O-antigen) was isolated by mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O60 and studied by sugar and methylation analyses as well as 1H and 13C NMR spectroscopy, including 2D ROESY and 1H,13C HMBC experiments in D2O and a ROESY experiment in a 9:1 H2O–D2O mixture to reveal correlations for NH protons. It was found that the polysaccharide is built up of linear pentasaccharide repeating units containing an amide of d-glucuronic acid with l-serine and has the following structure:The O-antigen studied is structurally and serologically closely related to the O-antigen of Proteus vulgaris O44.  相似文献   

13.
An O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O48 and studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including 2D COSY, TOCSY, ROESY and (1)H,(13)C HSQC and HMBC experiments. It was found that the polysaccharide is acidic and has a linear mono-O-acetylated tetrasaccharide repeating unit with the following structure: →3)-α-D-Manp-(1→2)-α-L-Fucp-(1→2)-β-D-GlcpA4Ac-(1→3)-α-D-GalpNAc-(1→.  相似文献   

14.
A neutral O-specific polysaccharide was obtained by mild acid hydrolysis of the lipopolysaccharide of the plant-growth-promoting bacterium Azospirillum lipoferum Sp59b. On the basis of sugar and methylation analyses along with 1D and 2D (1)H and (13)C NMR spectroscopy, including a NOESY experiment, the following structure of the branched hexasaccharide repeating unit of the O-polysaccharide was established: [carbohydrate structure: see text].  相似文献   

15.
The composition and structure of the O-polysaccharide of the lipopolysaccharide of Pseudomonas syringae pathovar garcae ICMP 8047 were studied using methylation analyses, Smith degradation, and 1H- and 13C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), total correlation spectroscopy (TOCSY), nuclear Overhauser effect spectroscopy (NOESY), and H-detected 1H,13C heteronuclear multiple-quantum coherence (HMQC) experiments. The polysaccharide was found to contain L-rhamnose and 3-acetamido-3, 6-dideoxy-D-galactose (D-Fuc3NAc) in the ratio 4:1 and to consist of two types of pentasaccharide repeating units. The major (1) and minor (2) repeating units differ from each other only in the position of substitution of one of the rhamnose residues in the main chain. Similar structural heterogeneity has been reported formerly in O-polysaccharides of some other P. syringae strains having a similar monosaccharide composition. A Fuc3NAc residue is attached to the main rhamnan chain as a side chain by a (alpha1-->4) glycosidic linkage; this has not hitherto been described in P. syringae: [figure].  相似文献   

16.
Citrobacter rodentium is the etiologic agent of transmissible murine colonic hyperplasia (TMCH) and is the only Citrobacter species known to possess virulence factors homologous to human enteropathogenic and enterohemorrhagic Escherichia coli. Members of this species are considered clonal and represent the only known attaching and effacing bacterial pathogen of mice and thus provides a useful animal model for studying the molecular basis of attaching and effacing pathology. The lipopolysaccharide (LPS) produced by C. rodentium has not been previously studied or its possible role as a virulence factor determined. The structure of the LPS has been undertaken as a first step in an investigation of its possible role in pathogenesis. The structure of C. rodentium (ATCC 51459, prototype TMCH isolate, original biotype 4280, previously designated DBS 100) LPS was determined from composition and methylation analyses, mass spectrometry, and two-dimensional nuclear magnetic resonance spectroscopy. The antigenic O-polysaccharide was found to be a high molecular mass branched polymer of repeating pentasaccharide units composed of 2-acetamido-2-deoxy-D-glucose (D-GlcNAc), d-glucose (D-Glc), and L-rhamnose (L-Rha) in the molar ratio 2 : 2 : 1 linked through phosphate, and has the structure: [structure: see text]  相似文献   

17.
An acidic O-polysaccharide isolated by mild acid hydrolysis from the lipopolysaccharide of Hafnia alvei PCM 1546 is composed of D-Gal, D-Glc, D-GlcA, D-GalNAc and O-acetyl groups in the ratios 1:1:1:2:1.6. On the basis of sugar and methylation analyses along with 1D and 2D 1H and 13C NMR spectroscopy, the following structure of the pentasaccharide repeating unit of the polysaccharide was established: [see equation in text].  相似文献   

18.
The following structure of the pentasaccharide repeating unit of an acidic O-polysaccharide of Hafnia alvei PCM 1529 was established by sugar and methylation analyses along with 1D and 2D 1H and 13C NMR spectroscopy: [Carbohydrate structure: see text].  相似文献   

19.
The O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O6 and studied by sugar and methylation analysis, selective hydrolytic removal of 3,6-dideoxy-L-xylo-hexose (colitose, Col), (1)H and (13)C NMR spectroscopy, including 2D (1)H,(1)H COSY, TOCSY, ROESY and H-detected (1)H,(13)C HSQC and HMBC experiments. The polysaccharide was found to have a branched pentasaccharide repeating unit with the following structure: [see text] Remarkably, the trisaccharide side chain of the O6-polysaccharide represents a colitose ('3-deoxy-L-fucose') analogue of the H type 1 (precursor) antigenic determinant.  相似文献   

20.
The structure of the antigenic O-chain polysaccharide of Flavobacterium columnare ATCC 43622, a Gram-negative bacterium that causes columnaris disease in warm water fish, was determined by high-field 1D and 2D NMR techniques, MS, and chemical analyses. The O-chain was shown to be an unbranched linear polymer of a trisaccharide repeating unit composed of 2-acetamido-2-deoxy-d-glucuronic acid (d-GlcNAcA), 2-acetamidino-2,6-dideoxy-l-galactose (l-FucNAm) and 2-acetamido-2,6-dideoxy-d-xylo-hexos-4-ulose (d-Sug) (1 : 1 : 1), having the structure: [structure: see text].  相似文献   

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