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PubMed1985

[Antigenic bacterial polysaccharides. 14. Structure of the O-specific polysaccharide chain of a lipopolysaccharide from Pseudomonas aeruginosa (Lányi)].

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.

Antigens, Bacterial↗
PubMed1986

[Antigenic polysaccharides of bacteria. 17. The structure of O-specific polysaccharide chain of Pseudomonas aeruginosa X (Meitert) lipopolysaccharide].

O-Specific polysaccharide composed of L-rhamnose and 2-acetamido-2-deoxy-D-mannose was obtained on mild acid degradation of P. aeruginosa X (Meitert classification) lipopolysaccharide. On the basis of non-destructive analis using 1H, 13C NMR spectroscopy and Klyne's rule calculation, as well as chemical methods (acid hydrolysis, methylation, Smith degradation), it was established that the polysaccharide is built up of disaccharide repeating units of the following structure: ----4)-alpha-L-Rha-(1----3)-beta-D-ManNAc-(1----.

Antigens, Bacterial↗
PubMed1987

[Antigenic polysaccharides of bacteria. 21. The structure of O-specific polysaccharide chains and serological specificity of lipopolysaccharides from 7 Pseudomonas aeruginosa immunotypes].

On mild acid degradation on lipopolysaccharides of seven Pseudomonas aeruginosa immunotypes, O-specific polysaccharides were obtained and their structures established. A peculiar feature of the polysaccharides is the presence of various, mostly acidic, mono- and diaminosugars, many of which have not previously been found in nature. The absence of serological cross-reactions (inhibition of passive haemagglutination) between lipopolysaccharides of seven immunotypes correlates with the absence of any common oligosaccharide fragments in their O-specific chains. The data obtained revealed structural and serological interrelations between O-antigens of seven immunotypes and P. aeruginosa O-serotypes, and showed that immunotypes 1 and 7 should be included into the serological classification scheme as individual O-serotypes.

Antigens, Bacterial↗
PubMed1988

[Antigenic polysaccharides of bacteria. 25. Structure of the O-specific polysaccharide chain of Pseudomonas cepacia 673/2 lipopolysaccharide containing L-glycero-D-manno-heptose].

O-Specific polysaccharide, consisting of D-rhamnose and L-glycero-D-manno-heptose (LD-Hep) in a 2 : 1 ratio, was obtained on the mild acid degradation of the Pseudomonas cepacia IMV 673/2 lipopolysaccharide; monosaccharide LD-Hep has not previously been found in O-specific chains of lipopolysaccharides. On the basis of methylation and 13C-NMR data, it was concluded that the polysaccharide is composed of trisaccharide repeating units having the following structure: ----3)-alpha-D-Rha-(1----3)-alpha-D-Rha-(1----2)-alpha-LD-Hep-(1----

Antigens, Bacterial↗
PubMed1988

[Antigenic polysaccharides of bacteria. 27. Structure of the O-specific polysaccharide chain of lipopolysaccharides from Pseudomonas syringae pv. atrofaciens 2399, phaesolica 120a and Pseudomonas holci 8299 belonging to serotype VI].

Lipopolysaccharides from Pseudomonas syringae pvs atrofaciens 2399. phaseolicola 120a and Pseudomonas holci 8299, belonging to serogroup VI. possess an identical polysaccharide chain composed of D-rhamnose and D-fucose. On the hasis of methylation, partial acid hydrolysis, 1H- and 13C-NMR data, it was concluded that the backbone of the polysaccharide represents D-rhamnan built up of tetrasaccharide repeating units and alpha-D-fucofuranose residues are attached to the backbone as the monosaccharide branches. The following structure of the repeating unit is established: (Formula: see text).

Antigens, Bacterial↗
PubMed1988

[Antigenic polysaccharides of bacteria. 31. The structure of the O-specific polysaccharide chain of Pseudomonas aurantiaca IMB 31 lipopolysaccharide].

The O-specific polysaccharide chain of the Pseudomonas aurantiaca IMV 31 lipopolysaccharide contains N-acetyl-L-fucosamine (FucNAc) and di-N-acetyl-D-bacillosamine (2,4-diacetamido-2,4,6-trideoxyglucose, Bac(NAc)2) in the ratio 2:1. On the basis of methylation, solvolysis with anhydrous hydrogen fluoride, and computer-assisted analysis of 13C-NMR spectrum, it was concluded that the trisaccharide repeating unit of the polysaccharide possesses the following structure: structure: ----3)-beta-D-Bac(NAc)2-(1----3)-alpha-L-FucNAc-(1----3)-alpha-L- FucNAc-(1----.

Antigens, Bacterial↗
PubMed1988

[Antigenic polysaccharides of bacteria. 32. The structure of O-specific polysaccharide chains of Pseudomonas cepacia serotype B and E lipopolysaccharides containing D-fucose].

On the basis of acid hydrolysis, methylation, 1H and 13C NMR analysis, and calculation of specific optical rotation, the following structures were established for O-specific polysaccharides of Pseudomonas cepacia serotypes B and E: ----3)-beta-D-Galf-(1----3)-alpha-D-Fucp-(1----serotype B ----3)-beta-D-GlcpNAc-(1----3)-alpha-D-Fucp-(1----serotype E A characteristic feature of the polysaccharides is the presence of D-fucose, rather rare for bacterial antigens.

Antigens, Bacterial↗
PubMed2003

Biosynthesis and assembly of Group 1 capsular polysaccharides in Escherichia coli and related extracellular polysaccharides in other bacteria.

Extracellular and capsular polysaccharides (EPSs and CPSs) are produced by a wide range of bacteria, including important pathogens of humans, livestock, and plants. These polymers are major surface antigens and serve a variety of roles in virulence, depending on the biology of the producing organism. In addition to their importance in disease, some EPSs also have industrial applications as gelling and emulsifying agents. An understanding of the processes involved in the synthesis and regulation of CPSs and EPSs therefore potentially contributes to an understanding of the disease state, surface expression of protective antigens, and modulation of polymer structure to give defined physical properties. Escherichia coli has provided important model systems for EPS and CPS biosynthesis. Here we describe current knowledge concerning assembly of the Group 1 CPSs of E. coli and the conservation of similar mechanisms in other bacteria.

Antigens, Bacterial↗
PubMed1976

[Analysis of polysaccharides used as food additives iv. Gaschromatographic identification and determination of neutral components in polysaccharide-hydrolysates (author's transl)].

The monosaccharides, which are obtained by hydrolytic cleavage of the polysaccharid containing stabilisators, can be separated gaschromatographically by the way of their aldonitrilacetates. After hydrolysis, the mixtures are neutralized by an anion exchanger, evaporated to dryness, converted in pyridin with hydroxylamin to the aldoximes and hereafter with acetic anhydride to the aldonitrilacetates. Dissolved in chloroform, these compounds are used for gaschromatographic separations; only one peak is obtained for each sugar. This is a great advantage to the previous methods, where the anomeric constellations lead up of five peaks for one sugar compound and for complicated sugar mixture, it therefore was difficult to evaluate their gaschromatograms.

Chromatography, Gas↗
PubMed1978

[Analysis of polysaccharides used as food additives. VI. Identification of mixtures of polysaccharides by methylation analysis (author's transl)].

Polysaccharide mixtures used as stabilizers having identical sugar units, but differing in their linkages can be identified with confidence by means of methylation analysis. Such mixtures are methylated with sodium hydride and methyl iodide in anhydrous dimethylsulfoxide. The methylated products are acid hydrolyzed and the resulting methyl sugars are separated and identified by thinlayer- or gaschromatography.

Chromatography, Gas↗
PubMed1994

Quantification of polysaccharide in Haemophilus influenzae type b conjugate and polysaccharide vaccines by high-performance anion-exchange chromatography with pulsed amperometric detection.

A sensitive method for the quantification of polysaccharide (PS) in Haemophilus influenzae type b (Hib) conjugate and PS vaccines has been developed. It is based on measurement of the Hib PS subunit after depolymerization of the PS in sodium hydroxide to produce the subunit, which is characterized by chemical composition and 31P n.m.r. analyses as ribitol-ribose-phosphate. The Hib vaccines were first treated with 0.1 M sodium hydroxide. The Hib PS subunit in the treated vaccines was then analysed directly by high-performance anion-exchange chromatography using a CarboPak PA-1 column, and quantified by pulsed amperometric detection. The PS contents of three conjugate vaccines and three PS vaccines from different manufacturers were determined. Their values were in the expected ranges. This method is particularly useful for vaccines with a sugar stabilizer such as lactose which would interfere with the colorimetric orcinol assay currently used for determination of the PS. The method can measure 0.1 microgram of PS and its sensitivity is at least 30-fold higher than that of the orcinol assay. It may be used for stability studies of conjugate vaccines since a breakdown as low as 5% of the PS from the PS-protein conjugates would be detected.

Chromatography, Ion Exchange↗
PubMed2005

Full assignment of the 1H and 13C spectra and revision of the O-acetylation site of the capsular polysaccharide of Streptococcus pneumoniae Type 33F, a component of the current pneumococcal polysaccharide vaccine.

The structure of the capsular polysaccharide from Streptococcus pneumoniae Type 33F was originally determined by a combination of chemical methods and limited use of NMR spectroscopy [Can. J. Biochem. Cell Biol.1984, 62, 666-677]. We report full 1H and 13C assignments and confirm the structure of the saccharide repeat unit, but find that the site of O-acetylation is O-2 of the -->5)-beta-D-Galf, rather than the -->3)-beta-D-Galf residue. We find that a slightly higher percentage of the repeat units are O-acetylated: [carbohydrate: see text].

Acetylation↗
PubMed2000

The immunostimulating activities of anti-tumor polysaccharide from K1 capsular (polysaccharide) antigen isolated from Klebsiella pneumoniae.

We have previously shown that K1 capsular polysaccharide antigen (K1CPS) of Klebsiella exhibits anti-tumor activities. In the present study, we examined the effect of K1CPS on cytotoxic effector cells. We found that K1CPS could activate many cytotoxic effector cells including alloreactive cytotoxic T cells and tumor-infiltrating lymphocytes (TILs). Moreover, K1CPS could increase the anti-tumor activity of lymphokine-activated killer (LAK) cells, both in vitro and in vivo. The i.p. injection of K1CPS in low dose could enhance the LAK cytotoxicity and the effect was further potentiated by coculture of LAK cells with K1CPS and low concentration of murine rIL-2 in vitro. The phenotypic characterization revealed that K1CPS might contribute to the increase in CD3+ LAK cell subpopulation by its in vivo priming effect. In addition, the K1CPS-treated LAK cells were able to inhibit the growth of WEHI-164 tumor cells in vivo in Winn-type inhibition assay. Subcutaneous (s.c.) and intraperitoneal (i.p.) adoptive infusion of LAK cells (splenocytes from K1CPS-treated WEHI-164-bearing mice cultured with K1CPS-plus-rIL-2) into WEHI-164 sarcoma-bearing mice could slightly cause regression in terms of tumor diameter, and more significantly in sarcoma weight.

Adjuvants, Immunologic↗
PubMed1998

Immunogenicity of Streptococcus pneumoniae type 6B and 14 polysaccharide-tetanus toxoid conjugates and the effect of uncoupled polysaccharide on the antigen-specific immune response.

The immunogenicity of two types of Streptococcus pneumoniae capsular polysaccharide-tetanus toxoid conjugates (PS6BTT and PS14TT) was evaluated in mice. Both conjugates induced high titres of high avidity type-specific anti-PS IgG, which include all IgG isotypes except IgG2a. Repeated immunization resulted in booster responses in both cases. The antibodies induced exhibited opsonic activity, as measured in an in vitro opsonophagocytosis assay, using the mouse macrophage cell line RAW-264. Furthermore, the influence of spiking PS6BTT with free PS6B of either 1000 kDa (native) or 37 kDa was investigated. The results indicate that not only the amount but also the molecular weight of the free PS6B present in the conjugate vaccine affect the anti-PS6B immune response. Large amounts of free PS6B of both molecular weights decrease each anti-PS6B IgG isotype response. However, unlike admixture of the low molecular weight PS6B, addition of the high molecular weight PS6B leads to a rather persistent state of unresponsiveness.

Animals↗
PubMed2001

Polysaccharide--polynucleotide complexes. 2. Complementary polynucleotide mimic behavior of the natural polysaccharide schizophyllan in the macromolecular complex with single-stranded RNA and DNA.

Schizophyllan is an extracellular polysaccharide consisting of a beta-1,3-D-glucan main chain and exists as a triple helix in water and as a single chain in dimethyl sulfoxide (DMSO). When the single chain of schizophyllan (s-SPG) was mixed with poly(C), poly(A), poly(dA), or poly(dT), they form a macromolecular complex. On the other hand, poly(G), poly(U), poly(I), poly(dG), and poly(dC) do not. This nucleotide specificity evidences that the hydrogen bonds are essential to form the complex, because the former nucleotides have an unoccupied hydrogen-bonding site and the latter ones use the hydrogen-bonding sites in the intramolecular aggregation (i.e., such as the G quartet for poly(G) and poly(dG) and the U hairpin for poly(U)). The hypochromic effect and the increment in the circular dichroism (CD) intensity are observed in accordance with the complex formation. These facts indicate that the base stacking is enhanced in the complex. The solvent-composition (DMSO/water) dependence demonstrates that the hydrophobic interaction is important to form the complex as well as the hydrogen-bonding interaction. With increasing temperature the complex dissociates cooperatively and the melting curve enables the thermodynamic parameters to be evaluated (delta H = -60 to 70 kcal mol-1 and delta S = -150 to 200 cal mol-1 K-1). These values are comparable with those for double helix DNA. Namely, the complex can be characterized by enhancement of the base stacking, cooperative dissociation, the similar thermodynamic parameters to DNA, and combination of the hydrogen-bonding and hydrophobic interactions to form the higher-order structure. These facts surprisingly coincide with characters of the double helix of DNA. In other words, the s-SPG molecule behaves as if it were a complementary polynucleotide chain for the corresponding polynucleotide. Furthermore, stoichiometric study suggested that the complex structure is a triple helix consisting of two s-SPG and one poly(C) or poly(A) chains.

Carbohydrate Conformation↗
PubMed2006

Role of the carbohydrate binding site of the Streptococcus pneumoniae capsular polysaccharide type 3 synthase in the transition from oligosaccharide to polysaccharide synthesis.

The type 3 synthase catalyzes the formation of the Streptococcus pneumoniae type 3 capsular polysaccharide [-3)-beta-D-GlcUA-(1, 4)-beta-D-Glc-(1-]n. Synthesis is comprised of two distinct catalytic phases separated by a transition step whereby an oligosaccharylphosphatidylglycerol primer becomes tightly bound to the carbohydrate acceptor recognition site of the synthase. Using the recombinant synthase in Escherichia coli membranes, we determined that a critical oligosaccharide length of approximately 8 monosaccharides was required for recognition of the growing chain by the synthase. Upon binding of the oligosaccharide-lipid to the carbohydrate recognition site, the polymerization reaction entered a highly processive phase to produce polymer of high molecular weight. The initial oligosaccharide-synthetic phase also appeared to be processive, the duration of which was enhanced by the concentration of UDP-GlcUA and diminished by an increase in temperature. The overall reaction approached a steady state equilibrium between the polymer- and oligosaccharide-forming phases that was shifted toward the former by higher UDP-GlcUA levels or lower temperatures and toward the latter by lower concentrations of UDP-GlcUA or higher temperatures. The transition step between the two enzymatic phases demonstrated cooperative kinetics, which is predicted to reflect a possible reorientation of the oligosaccharide-lipid in conjunction with the formation of a tight binding complex.

Bacterial Capsules↗