Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “POLYSACCHARIDES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources

Activity of CMP-2-keto-3-deoxyoctulosonic acid synthetase in Escherichia coli strains expressing the capsular K5 polysaccharide implication for K5 polysaccharide biosynthesis.

The activity of the cytoplasmic CMP-2-keto-3-deoxyoctulosonic acid synthetase (CMP-KDO synthetase), which is low in Escherichia coli rough strains such as E. coli K-12 and in uncapsulated strains such as E. coli O111, was significantly elevated in encapsulated E. coli O10:K5 and O18:K5. This enzyme activity was even higher in an E. coli clone expressing the K5 capsule. This and the following findings suggest a correlation between elevated CMP-KDO synthetase activity and the biosynthesis of the capsular K5 polysaccharide. (i) Expression of the K5 polysaccharide and elevated CMP-KDO synthetase activity were observed with bacteria grown at 37 degrees C but not with cells grown at 20 degrees C or below. (ii) The recovery kinetics of capsule expression of intact bacteria, in vitro K5 polysaccharide-synthesizing activity of bacteria, and CMP-KDO synthetase activity of bacteria after temperature upshift from 18 to 37 degrees C were the same. (iii) Chemicals which inhibit capsule (polysaccharide) expression also inhibited the elevation of CMP-KDO synthetase activity. The chromosomal location of the gene responsible for the elevation of this enzyme activity was narrowed down to the distal segment of the transport region of the K5 expression genes.

Cloning, Molecular↗

Enzyme immunoassay for detection of immunoglobulin G (IgG), IgM, and IgA antibodies against type 6B pneumococcal capsular polysaccharide and cell wall C polysaccharide in chinchilla serum.

Conjugation of the capsular polysaccharides of Streptococcus pneumoniae to protein carriers has introduced a new generation of pneumococcal vaccines which may be efficacious in preventing pneumococcal otitis media during infancy. The chinchilla model has been used extensively for studying the pathogenesis of pneumococcal otitis media and for testing the efficacy of early pneumococcal capsular polysaccharide (PCP) vaccines, but immunologic studies in the chinchilla have been limited by the lack of antibodies against specific immunoglobulin isotypes. By using affinity-purified rabbit immunoglobulin G (IgG) anti-chinchilla IgG, IgM, and IgA, we developed a sensitive enzyme immunoassay that is highly specific for IgG, IgM, and IgA antibodies against type 6B PCP (anti-6B) and against C polysaccharide in chinchilla serum. Antibody titers increased in serum from five chinchillas immunized with a type 6B outer membrane protein complex vaccine. Increases of anti-6B IgG and IgM antibody titers were more striking than increases of anti-6B IgA or anti-C polysaccharide IgG, IgM, or IgA titers were.

Animals↗

Polysaccharides in fungi. XXXII. Hypoglycemic activity and chemical properties of a polysaccharide from the cultural mycelium of Cordyceps sinensis.

Crude polysaccharides were obtained from a hot-water extract and alkaline extracts of the cultural mycelium of Cordyceps sinensis. They showed significant activity in normal mice and streptozotocin-induced diabetic mice as a result of intraperitoneal (i.p.) injection. A crude polysaccharide (CS-OHEP) obtained from 5% sodium hydroxide extract slightly lowered the plasma glucose level in normal mice by oral (p.o.) administration. A neutral polysaccharide (CS-F30) exhibited higher hypoglycemic activity than its crude polysaccharide (CS-OHEP), exhibited by i.p. injection, and it significantly lowered the glucose level by p.o. administration (50 mg/kg). However, it hardly affected the plasma insulin level in normal mice. CS-F30 ([alpha]D + 21 degrees in water) is composed of galactose, glucose and mannose (molar percent, 62:28:10), and its molecular weight is about 45000.

Animals↗

Antibody responses to polysaccharide and polysaccharide-conjugate vaccines after treatment of Hodgkin disease.

OBJECTIVE: To compare the immunogenicity of polysaccharide-conjugate vaccines with that of polysaccharide vaccines in patients previously treated for Hodgkin disease. DESIGN: All patients were immunized with Haemophilus influenzae type b (HIB)-conjugate and 4-valent meningococcal polysaccharide vaccines. Subgroups of patients were randomly assigned to receive either 23-valent pneumococcal polysaccharide vaccine or a 7-valent pneumococcal-conjugate vaccine that links seven pneumococcal serotypes to the outer membrane protein complex of Neisseria meningitidis. PATIENTS: 144 patients who had completed treatment for Hodgkin disease, which had been diagnosed at least 2 years before the study. MEASUREMENTS: Antigen-specific antibody concentrations before and 3 to 6 weeks after immunization; number of persons who achieved anti-HIB antibody concentrations considered to be in the protective range. RESULTS: The geometric mean anti-HIB antibody concentration increased from 1.79 micrograms/mL before immunization to 54.1 micrograms/mL after; the percentage of persons with antibody concentrations in the protective range increased from 62% before immunization to 99% after. Patients immunized with 23-valent pneumococcal vaccine had a geometric mean pneumococcal antibody concentration after immunization (9.15 micrograms/mL) that was similar to that of healthy controls (10.0 micrograms/mL) for the seven serotypes measured. In contrast, patients who received 7-valent pneumococcal-conjugate vaccine had a significantly lower mean response compared with patients who received 23-valent; their geometric mean antibody concentration after immunization was 4.95 micrograms/mL (P = 0.005). CONCLUSION: A single dose of HIB-conjugate vaccine was immunogenic in patients who had completed treatment for Hodgkin disease diagnosed at least 2 years before immunization. In addition, responses to the 23-valent pneumococcal and 4-valent meningococcal vaccines were equivalent to those seen in healthy controls. Finally, patients had a significantly lower response to a single dose of 7-valent pneumococcal-conjugate vaccine than to 23-valent vaccine.

Bacterial Capsules↗

[Isolation and structural analysis of a new polysaccharid, Streptomyces polysaccharide].

OBJECTIVE: To isolate and purify a new polysaccharid Streptomyces polysaccharid polysaccharide (SMP ), from cultured broth of a Streptomyces sp.strain and perform its structural analysis. METHODS: Ethanol was used to precipitate the polysaccharides and macromolecules from the broth. The proteins in the precipitate were removed by Sevage method and purification of SMP was carried out by DEAE-celluloseion-exchange chromatography and Sephadex G-25 gel filtration. The chemical structure of the SMP was determined by combined application of high performance liquid chromatography (HPLC), UV, IR and 1H-NMR spectroscopy, supplemented by periodate oxidation and Smith degradation. RESULTS: The purified SMP was neutral by a relative molecular mass of approximately 4 855. Sugar analysis showed that SMP contained glucose and fructose residues in an approximate molar ratio of 22:1 (10.96 to 0.48). The glycosidic linkages were estimated to be (1-6)- alpha-D- pyranoside form. CONCLUSION: SMP is characterized as a (1-6)- alpha-D- pyranose.

Polysaccharides, Bacterial↗

[Chemistry of polysaccharide Lzps-1 from Ganoderma lucidum spore and anti-tumor activity of its total polysaccharides].

AIM: To study the structure and anti-tumor activity of polysaccharide from Ganoderma lucidum spore treated with microwave. METHODS: DEAE-cellulose and Sephadex G-50 column chromatography were used to isolate and purify the polysaccharide whose structure was characterized by using chemical and spectral methods. RESULTS AND CONCLUSION: One polysaccharide, named Lzps-1 was obtained from the water extract, with its molecular weight estimated by HPGPC to be 8000. Its structure was investigated to be glucan. The total polysaccharides, Lzps processed antitumor activity against sarcoma 180 and Lewis lung cancer in mice and enhanced the NK cell activity. Lzps-1 is obtained for the first time from Ganoderma spore Lzps has anti-tumor activity.

Animals↗

[Somatic antigens of Shigella and Escherichia coli. Determination of the structure of O-specific polysaccharide from Shigella boydii type 12 and its serological properties compared with the O-specific polysaccharide from Escherichia coli].

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.

Antigens, Bacterial↗

Binding of heparin fractions and other polysulfated polysaccharides to plasma fibronectin: effects of molecular size and degree of sulfation of polysaccharides.

Heparin was divided into four fractions on fibronectin-Sepharose. The higher affinity fraction for fibronectin was larger in molecular size, higher in sulfate content and higher in affinity for anti-thrombin III. Together with these heparin fractions, the following three series of heparin samples were examined to compare the affinity for fibronectin-Sepharose: four fractions separated on Sephadex G-100; five fractions separated on antithrombin III-Sepharose, and six partially and completely N-desulfated heparins. The result showed that the affinity of heparin for fibronectin was dependent exclusively on its molecular size, and that an appropriate level of sulfate content in heparin (1.9-2.4 mol/disaccharide) was essential for the affinity. The sulfated preparations of glycosaminoglycans (heparan sulfate, dermatan sulfate and chondroitin 4-sulfate) and neutral polysaccharides (amylose and dextran) having higher sulfate content than heparin were found to display higher affinity for fibronectin than heparin. This suggested that highly sulfated polysaccharides showed potent affinity irrespective of their polysaccharide structure. The sulfated chondroitin 4-sulfate having a sulfate content and molecular size comparable to those of heparin was inferior to heparin with respect to affinity. A competitive dissociation experiment indicated that heparin and other polysulfated polysaccharides share a common binding site on the fibronectin molecule.

Animals↗

Different local therapeutic effects of various polysaccharides on MH134 hepatoma in mice and its relation to inflammation induced by the polysaccharides.

The local antitumor activities and inflammation-inducing activities of various antitumor polysaccharides were examined and the relation between the two types of activity was studied. The tested antitumor polysaccharides included MG (a mannoglucan prepared from the culture fluid of Microellobosporia grisea), lentinan, bacterial lipopolysaccharide, TAK (a glucan from Alcaligenes faecalis) and their derivatives. Local antitumor activity was tested by intratumoral administration of the polysaccharides 4, 7 and 10 days after inoculation of MH134 hepatoma intradermally (id) into the abdomen of C3H/He mice. MG and its derivatives showed strong local antitumor activity. Inflammation-inducing activity was assayed by measuring foot-pad swelling and accumulation of iv-injected 51Cr-labeled spleen cells after injection of the test materials into the footpads of C3H/He mice. TAK had the strongest inflammation-inducing activity among the polysaccharides tested. No close correlation was found between the local antitumor activity and the inflammation-inducing activity.

Animals↗

Complement-induced solubilization of C-reactive protein-pneumococcal C-polysaccharide precipitates: evidence for covalent binding of complement proteins to C-reactive protein and to pneumococcal C-polysaccharide.

Insoluble precipitates between C-reactive protein and pneumococcal C-polysaccharide were solubilized by fresh but not heat-inactivated human serum. Solubilization was dependent on the C-reactive protein to C-polysaccharide ratio and the serum concentration and proceeded optimally at 37 degrees C. On 12 to 30% sucrose density gradients solubilized complexes sedimented as a broad peak between the 7S region and the bottom of the tube. In C2-deficient human serum, solubilization was delayed by 30 min and then proceeded at a slow rate. Immunoprecipitation experiments indicated that C3, C4, C5, and to a lesser extent C1q were deposited on solubilized complexes. After dissociating solubilized complexes with EDTA, a considerable percentage of C-polysaccharide coprecipitated with C3, C4, and C5, whereas C-reactive protein coprecipitated with only C3. SDS-PAGE analysis of solubilized precipitates indicated the formation of covalent complexes between fragments of C3 and both C-polysaccharide and C-reactive protein.

C-Reactive Protein↗

[Antigenic bacterial polysaccharides. Structure of O-specific polysaccharides from Pseudomonas cepacia serogroups C, I, O1, and O4].

Like some Pseudomonas cepacia serogroups studied earlier, serogroups C, I (Nakamura), O1 and O4 (Heidt) are characterized by the presence of at least two structurally different O-antigenic polysaccharide chains in cell-wall lipopolysaccharides. On the basis of acid hydrolysis, methylation, 1H- and 13C-NMR spectroscopy, including computer-assisted 13C-NMR-based analysis, the complete structures of the predominant polysaccharides of serogroups I (I), C and O4 (III) and the minor polysaccharides of serogroups I (II) and O1 (V) were established, and the structure of the predominant polysaccharide of serogroup O1 (IV) established earlier (Cox A. D., Wilkinson S. G.@Carbohydr. Res. 1990. V. 195. No 2. P. 295-301) was confirmed.

Burkholderia cepacia↗

An antigenic polysaccharide from Campylobacter coli serotype O:30. Structure of a teichoic acid-like antigenic polysaccharide associated with the lipopolysaccharide.

A water-soluble antigenic polysaccharide of high M(r) associated with the lipopolysaccharide has been isolated from phenol-water extraction of cells of Campylobacter coli serotype O:30. The polysaccharide and oligosaccharide degradation products formed on O-dephosphorylation and by periodate oxidation followed by reduction have been investigated by one- and two-dimensional 1H, 13C, and 31P NMR. It is concluded that the antigenic polysaccharide has a teichoic acid-like structure with a poly-Ribitol phosphate, [5-Ribitol-1-P]n, backbone with side chains at O-2 of O-(6-deoxy-beta-D-talo-heptopyranosyl)-(1-->4)-(2-acetylamino-2-deoxy-beta-D- glucopyranosyl) units. The structure is unusual in Gram-negative bacteria and is unique in possessing 6-deoxy-D-talo-heptose as a constituent sugar. Evidence for the relationship of the antigenic polysaccharide to the lipopolysaccharide of low M(r) is discussed.

Campylobacter coli↗

[The relationship between the immunological efficacy of a dried meningococcal group-A polysaccharide vaccine and the molecular parameters of the group-A polysaccharide].

This work deals with the problem of relationship between the molecular parameters of group A meningococcal polysaccharide and its immunological effectiveness for laboratory animals and humans. The depolymerization of group A polysaccharide contained in the vaccine leads to a decrease in its capacity of inducing the production of hemagglutinating (19S and 7S) and bactericidal IgA antibodies in humans, as well as inducing an increase in the number of cells producing IgA antibodies in the spleen of immunized mice and the appearance of circulating IgA antibodies in their sera. As shown in this investigation, fully developed immune response to group A meningococcal vaccine may be achieved in humans only if the content of group A high-molecular polysaccharide in the vaccine is not less than 70%. Mice have been recommended as an experimental model for the prognostication of the effectiveness of meningococcal polysaccharide vaccines and for their control in the process of manufacture instead of currently used titration of bacteriolysins in the sera of immunized humans.

Animals↗

Computer modeling of polysaccharide-polysaccharide interactions: an approach to the kappa-carrageenan-mannan case.

A computer program SAINT has been developed for the investigation of the structure and for the prediction of minimum-energy structure of polysaccharide-polysaccharide complexes. The energy minimization is carried out on internal geometrical parameters--namely bond angles, torsional angles, and five parameters describing the mutual orientations of polysaccharide chains. For this purpose, the nonderivative method of conjugated directions is used. This procedure was applied to computer modeling of an idealized model of the binary gelling kappa-carrageenan and galactomannan system. It is shown that the interaction between two chains influences the structure of the individual polysaccharide molecule and that in the minimum-energy structures of the complex, the conformation of the chains does not correspond to the lowest energy.

Carbohydrate Sequence↗

IgG subclass distributions in anti-hapten and anti-polysaccharide antibodies induced by haptenated polysaccharides.

Mice were immunized with hapten [NIP, (4-hydroxy-5-iodo-3-nitrophenyl)acetyl or TNP (2,4,6-trinitrophenyl)] conjugates of Ficoll or pneumococcal polysaccharide type 14 (S14), and they were bled on days 10 or 14. Anti-hapten and anti-polysaccharide antibodies were determined from the sera or from fractions (IgM + IgA). IgG1, IgG2a, IgG3 or IgG2b separated by a gradual acid elution from protein A. Approximately one-half of both anti-hapten and anti-polysaccharide antibodies was found in the IgM + IgA fraction. The subclass distribution of the IgG antibodies was dependent on the antigenic determinants. Polysaccharide antibodies were mostly in the IgG3 fraction (36-62%) and in the IgG1 fraction (18-36%). Hapten IgG antibodies were mostly in the IgG1 fraction (38-74%): each of the other three subclasses contributed the average of 13%. These results provide the first evidence that antibodies to different determinants of one antigen have grossly different isotype distributions.

Animals↗

Structures of the O-specific polysaccharides from Yokenella regensburgei (Koserella trabulsii) strains PCM 2476, 2477, 2478, and 2494: high-resolution magic-angle spinning NMR investigation of the O-specific polysaccharides in native lipopolysaccharides and directly on the surface of living bacteria.

The structures of the carbohydrate O-specific side-chain moiety of the lipopolysaccharides (LPS) of Yokenella regensburgei, strains PCM 2476, 2477, 2478, and 2494, have been investigated by (1)H and (13)C NMR, fast atom bombardment tandem mass spectrometry (FAB-MSMS), matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry, methylation analysis, partial acid hydrolysis, and immunological methods. It was concluded that the O-specific polysaccharides of strains 2476, 2477, 2478, and 2494 are composed of the same basic trisaccharide repeating unit having the structure -->3)-alpha-D-FucpNAc-(1-->2)-L-alpha-D-Hepp-(1-->3)-6-deoxy -alpha-L- Talp-(1-->, in which L-alpha-D-Hepp is L-glycero-alpha-D-manno-heptopyranose. The detailed analysis revealed, however, differences in O-acetylation patterns of the 6-deoxy-L-talose residue, with 2- and 4-O-acetyl disubstituted -->3)-6-deoxy-alpha-L-Talp-(1--> in strain PCM 2476 and a 2-O-acetylated residue in strains 2477, 2478, and 2494. These structures represent novel, trisaccharide repeating units of bacterial O-antigens that are characteristic and unique to the Y. regensburgeispecies. By use of the high-resolution magic-angle spinning (HR-MAS) technique, (1)H NMR spectra of the O-polysaccharides directly in isolated LPS were obtained. This allowed for almost full assignment and structural determination of the polysaccharide. By this technique the O-polysaccharide components were also observed in their original form directly on the surface of living bacterial cells.

Carbohydrate Conformation↗

[Antigenic polysaccharides of bacteria. 16. The structure of O-specific polysaccharide chain of Pseudomonas aeruginosa 025 (Wokatsch) lipopolysaccharide].

O-Specific polysaccharide built up of trisaccharide repeating units containing 3-acetamidino-2-acetamido-2,3-dideoxy-D-mannuronic acid (ManNAcAmA), 2,3-diacetamido-2,3-dideoxy-D-mannuronic acid (Man(NAc)2A), N-acetyl-D-fucosamine (FucNAc), and O-acetyl group was obtained on mild acid hydrolysis of P. aeruginosa O25 (Wokatsch classification) lipopolysaccharide. Basing on de-O-acetylation of polysaccharide with aqueous triethylamine accompanied by hydrolysis of acetamidino group to acetamido group, as well as on the 1H and 13C NMR data, the following structure of the repeating unit of the polysaccharide was established: (Formula: see text) P. aeruginosa O25 polysaccharide has the same carbohydrate skeleton as that of P. aeruginosa O3a,b (Lányi classification) and differs from the latter only by the presence of the O-acetyl group at position 4 of N-acetylfucosamine.

Antigens, Bacterial↗

[Antigenic polysaccharides of bacteria of the genus Shigella. Determination of the structure of polysaccharide chains of Shigella boydii type 9 lipopolysaccharide and detection of unusually high molecular weight glycolipid].

Specific acidic polysaccharide has been isolated from the Shigella boydii type 9 antigenic lipopolysaccharide after mild hydrolysis followed by chromatography on Sephadex G-50. The polysaccharide consists of D-glucose, D-glucuronic acid, 2-acetamido-2-deoxy-D-glucose, and L-rhamnose. From the results of methylation analysis, partial acid hydrolysis and 13C NMR data the structure of the repeating unit of the polysaccharide was deduced as follows: [----4)DGlcp(alpha 1----4)DGlcAp(beta 1----3)DGlcNAcp(alpha 1----3)LRhap(alpha 1----]n. The lipopolysaccharide from Sh. boydii 9 was fractionated by gel chromatography on the Sephadex G-200 column in a buffer containing sodium deoxycholate into three fractions. PAGE-SDS of the fractions obtained, 13C NMR- and chromato-mass-spectrometry data indicated that the three fractions contained the O-specific polysaccharide as the only carbohydrate component. The substance from the most high-molecular weight fraction contained unusually long O-specific chains (60,000 dalton). In the fat acid composition this fraction differed from other lipopolysaccharides by absence of beta-hydroxymyristic acid.

Antigens, Bacterial↗