Science.gov

Sample records for capsular polysaccharide structure

  1. Structurally altered capsular polysaccharides produced by mutant bacteria

    NASA Technical Reports Server (NTRS)

    Kern, Roger G. (Inventor); Petersen, Gene R. (Inventor); Richards, Gil F. (Inventor)

    1995-01-01

    Structurally altered capsular polysaccharides are produced by mutant bacteria. These polysaccharides are isolated by selecting a wild type bacterial strain and a phage producing degradative enzymes that have substrate specificity for the capsular polysaccharides produced by the wild type bacteria. Phage-resistant mutants producing capsular polysaccharides are selected and the structurally altered capsular polysaccharide is isolated therefrom.

  2. Method for producing capsular polysaccharides

    NASA Technical Reports Server (NTRS)

    Kern, Roger G. (Inventor); Petersen, Gene R. (Inventor); Richards, Gil F. (Inventor)

    1994-01-01

    Structurally altered capsular polysaccharides are produced by mutant bacteria. These polysaccharides are isolated by selecting a wild type bacterial strain and a phage producing degradative enzymes that have substrate specificity for the capsular polysaccharides produced by the wild type bacteria. Phage-resistant mutants producing capsular polysaccharides are selected and the structurally altered capsular polysaccharide is isolated therefrom.

  3. CAPSULAR POLYSACCHARIDE OF AZOTOBACTER AGILIS.

    PubMed

    COHEN, G H; JOHNSTONE, D B

    1964-12-01

    Cohen, Gary H. (University of Vermont, Burlington), and Donald B. Johnstone. Capsular polysaccharide of Azotobacter agilis. J. Bacteriol. 88:1695-1699. 1964.-Capsular polysaccharide from Azotobacter agilis strain 132 was recovered from washed cells by alkaline digestion. The polysaccharide was purified by centrifugation, repeated alcohol precipitation, Sevag deproteinization, and treatment with ribonuclease and charcoal-cellulose. Methods of isolation and purification appeared to provide a polymer showing no evidence of heterogeneity when examined by chemical and physical methods. Colorimetric, paper chromatographic, and enzymatic analyses on both intact and acid-hydrolyzed polysaccharide indicated that the polymer contained galactose and rhamnose at a molar ratio of approximately 1.0:0.7. A sialic acid-like component was also present in the polysaccharide. The study shows significant differences in the chemical composition of the extra-cellular polysaccharide of A. agilis and that of A. vinelandii. This adds further biochemical evidence for the right of these species to independent status.

  4. Synthesis of part structures of Cryptococcus neoformans serotype C capsular polysaccharide.

    PubMed

    Guazzelli, Lorenzo; McCabe, Orla; Oscarson, Stefan

    2016-10-04

    Cryptococcus neoformans is a fungal pathogen that can cause life-threatening infections in immunocompromised patients. The development of a vaccine based on the capsular polysaccharide of C. neoformans is still an open challenge due to the heterogeneity of the capsular polysaccharide and the difficulty of identifying protective epitopes. Therefore, construction of structurally defined part structures of the C. neoformans GXM capsule is in great demand. Herein is presented the synthesis of a 3-O-naphthalenylmethyl protected trisaccharide thioglycoside building block which is present in C. neoformans serotype C polysaccharide. Its property as a donor in a glycosylation reaction with a model acceptor has been evaluated together with its behaviour as an acceptor following removal of the temporary protecting group. The heavily branched hexasaccharide was obtained in good yields and excellent α-selectivity. The frame shifted octasaccharide structural triad motif for serotype C was also prepared following the same building block strategy. For the first time this structural motif, which is the most substituted amongst the four C. neoformans serotypes, was prepared. Three synthesized C. neoformans serotype C fragments of varying size, from penta-up to octasaccharide, were deprotected and will be included in unique glycoarrays to further investigate the possibility to develop a synthetic vaccine against this pathogen.

  5. Synthesis of oligosaccharides corresponding to structures found in capsular polysaccharides of Cryptococcus neoformans--II.

    PubMed

    Garegg, P J; Olsson, L; Oscarson, S

    1996-11-01

    Formula 1 depicts a generalized structure of the capsular polysaccharides of four serotypes of the opportunistic microorganism Cryptococcus neoformans, which appears as one of the major infections in the late stages of development of AIDS. Syntheses are now described of two tetrasaccharides with corresponding structures. These are methyl O-alpha-D-mannopyranosyl-(1-->3)-[O-beta-D-xylopyranosyl-(1-->2)] -O-alpha-D-mannopyranosyl-(1-->3)-alpha-D-mannopyranoside and methyl O-alpha-D-mannopyranosyl-(1-->3)-[O-beta-D-glucopyranosyluronic acid-(1-->2)]-O-alpha-D-mannopyranosyl-(1-->3)-alpha-D-mannopyranoside.

  6. Crystal structure of the capsular polysaccharide synthesizing protein CapE of Staphylococcus aureus.

    PubMed

    Miyafusa, Takamitsu; Caaveiro, Jose M M; Tanaka, Yoshikazu; Tanner, Martin E; Tsumoto, Kouhei

    2013-06-11

    Enzymes synthesizing the bacterial CP (capsular polysaccharide) are attractive antimicrobial targets. However, we lack critical information about the structure and mechanism of many of them. In an effort to reduce that gap, we have determined three different crystal structures of the enzyme CapE of the human pathogen Staphylococcus aureus. The structure reveals that CapE is a member of the SDR (short-chain dehydrogenase/reductase) super-family of proteins. CapE assembles in a hexameric complex stabilized by three major contact surfaces between protein subunits. Turnover of substrate and/or coenzyme induces major conformational changes at the contact interface between protein subunits, and a displacement of the substrate-binding domain with respect to the Rossmann domain. A novel dynamic element that we called the latch is essential for remodelling of the protein-protein interface. Structural and primary sequence alignment identifies a group of SDR proteins involved in polysaccharide synthesis that share the two salient features of CapE: the mobile loop (latch) and a distinctive catalytic site (MxxxK). The relevance of these structural elements was evaluated by site-directed mutagenesis.

  7. Structural analysis of the capsular polysaccharide from Campylobacter jejuni RM1221

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The complete genome of Campylobacter jejuni strain RM1221 (Penner serotype HS:53) was reported recently and contains a novel capsular polysaccharide (CPS) biosynthesis locus. Cell surface carbohydrates such as CPS are known to be important for bacterial survival and often contribute to pathogenesis....

  8. Neisseria meningitidis serogroup A capsular polysaccharide acetyltransferase, methods and compositions

    DOEpatents

    Stephens, David S [Stone Mountain, GA; Gudlavalleti, Seshu K [Kensington, MD; Tzeng, Yih-Ling [Atlanta, GA; Datta, Anup K [San Diego, CA; Carlson, Russell W [Athens, GA

    2011-02-08

    Provided are methods for recombinant production of an O-acetyltransferase and methods for acetylating capsular polysaccharides, especially those of a Serogroup A Neisseria meningitidis using the recombinant O-acetyltransferase, and immunogenic compositions comprising the acetylated capsular polysaccharide.

  9. Structure of the neutral capsular polysaccharide of Acinetobacter baumannii NIPH146 that carries the KL37 capsule gene cluster.

    PubMed

    Arbatsky, Nikolay P; Shneider, Mikhail M; Kenyon, Johanna J; Shashkov, Alexander S; Popova, Anastasiya V; Miroshnikov, Konstantin A; Volozhantsev, Nikolay V; Knirel, Yuriy A

    2015-09-02

    Capsular polysaccharide (CPS) was isolated from Acinetobacter baumannii NIPH146, and the following structure of branched pentasaccharide repeating unit was established by sugar analyses along with 1D and 2D NMR spectroscopy: In comparison to most other known capsular polysaccharides of A. baumannii, the CPS studied is neutral and lacks any specific monosaccharide component. The synthesis, assembly and export of this structure could be attributed to genes in a novel capsule biosynthesis gene cluster, designated KL37, which was found in the NIPH146 genome. The CPS of A. baumannii NIPH146 shares the α-d-Galp-(1→6)-β-d-Glcp-(1→3)-d-GalpNAc-(1→ trisaccharide fragment with the CPS units of several A. baumannii strains, including ATCC 17978 and LUH 5537 that carry the KL3 and KL22 gene clusters, respectively. KL37 contains two genes for glycosyltransferases that are related to two glycosyltransferase genes present in both KL3 and KL22, and the encoded proteins could be tentatively assigned to linkages between sugars in the CPS repeat.

  10. Structural determination of the K14 capsular polysaccharide from an ST25 Acinetobacter baumannii isolate, D46.

    PubMed

    Kenyon, Johanna J; Hall, Ruth M; De Castro, Cristina

    2015-11-19

    The structure of the capsular polysaccharide (CPS) recovered from D46, an extensively antibiotic resistant ST25 Acinetobacter baumannii clinical isolate, was elucidated. The structure was resolved on the basis of NMR spectroscopy and chemical analyses, and was found to contain a branched neutral pentasaccharide with a backbone composed of GalpNAc and Galp residues, all d configured, and a d-Glcp side group. The KL14 gene cluster found in the D46 genome includes genes for four glycosyltransferases but no modules for synthesis of complex sugars, and this is consistent with the structure of K14. The K14 structure and KL14 sequence clarify the relationship between the structure and K locus sequence for A. nosocomialis isolate LUH5541. The identity of the first sugar of the K14 repeat unit (K unit), and the functions of the four encoded glycosyltransferases and Wzy polymerase were predicted.

  11. Characterization of the structure and biological functions of a capsular polysaccharide produced by Staphylococcus saprophyticus.

    PubMed

    Park, Sunny; Kelley, Kathryn A; Vinogradov, Evgeny; Solinga, Robert; Weidenmaier, Christopher; Misawa, Yoshiki; Lee, Jean C

    2010-09-01

    Staphylococcus saprophyticus is a common cause of uncomplicated urinary tract infections in women. S. saprophyticus strain ATCC 15305 carries two staphylococcal cassette chromosome genetic elements, SCC(15305RM) and SCC(15305cap). The SCC(15305cap) element carries 13 open reading frames (ORFs) involved in capsular polysaccharide (CP) biosynthesis, and its G+C content (26.7%) is lower than the average G+C content (33.2%) for the whole genome. S. saprophyticus strain ATCC 15305 capD, capL, and capK (capD(Ssp), capL(Ssp), and capK(Ssp)) are homologous to genes encoding UDP-FucNAc biosynthesis, and gtaB and capI(Ssp) show homology to genes involved in UDP-glucuronic acid synthesis. S. saprophyticus ATCC 15305 CP, visualized by immunoelectron microscopy, was extracted and purified using anionic-exchange and size exclusion chromatography. Analysis of the purified CP by (1)H and (13)C nuclear magnetic resonance (NMR) spectroscopy and gas-liquid chromatography revealed two types of branched tetrasaccharide repeating units composed of the following: -4)-beta-Glc-(1-3)-Sug-(1-4)-beta-GlcA-(1- | beta-GlcNAc-(1-2) Sug represents two stereoisomers of 2-acetamido-2,6-dideoxy-hexos-4-ulose residues, one of which has an arabino configuration. The encapsulated ATCC 15305 strain was resistant to complement-mediated opsonophagocytic killing by human neutrophils, whereas the acapsular mutant C1 was susceptible. None of 14 clinical isolates reacted with antibodies to the ATCC 15305 CP. However, 11 of the 14 S. saprophyticus isolates were phenotypically encapsulated based on their resistance to complement-mediated opsonophagocytic killing and their failure to hemagglutinate when cultivated aerobically. Ten of the 14 clinical strains carried homologues of the conserved staphylococcal capD gene or the S. saprophyticus gtaB gene, or both. Our results suggest that some strains of S. saprophyticus are encapsulated and that more than one capsular serotype exists.

  12. Cellular immunity to Bacteroides fragilis capsular polysaccharide

    PubMed Central

    1982-01-01

    The polysaccharide capsule of Bacteroides fragilis has been shown to be important in the virulence of the organism. The capsular polysaccharide (CP) of B. fragilis has been extensively purified. Using a murine model of intraabdominal abscess formation, we have been able to demonstrate cellular immunity to the capsular polysaccharide of B. fragilis. Immunization of C57BL/10J mice with the CP over 5 wk prevents abscess formation when the mice are challenged with B. fragilis intraperitoneally. This immunity can be transferred to naive mice with spleen cells from immune animals. The immune cells bear Thy-1.2 and Ly- 2.2 antigens. The immune response has been shown to be antigen specific, but not H-2 restricted. The possibility that these immune cells are suppressor T cells is discussed. The experimental system presented provides a model for the examination of the cellular interactions responsible for abscess formation and the cellular response to bacterial pathogens. PMID:6174672

  13. Masquerading microbial pathogens: Capsular polysaccharides mimic host-tissue molecules

    PubMed Central

    Cress, Brady F.; Englaender, Jacob A.; He, Wenqin; Kasper, Dennis; Linhardt, Robert J.; Koffas, Mattheos A. G.

    2014-01-01

    Summary Bacterial pathogens bearing capsular polysaccharides identical to mammalian glycans benefit from an additional level of protection from host immune response. The increasing prevalence of antibiotic resistant bacteria portends an impending post-antibiotic age, characterized by diminishing efficacy of common antibiotics and routine application of multifaceted, complementary therapeutic approaches to treat bacterial infections, particularly multidrug-resistant organisms. The first line of defense for most bacterial pathogens consists of a physical and immunological barrier known as the capsule, commonly composed of a viscous layer of carbohydrates that are covalently bound to the cell wall in Gram-positive bacteria or often to lipids of the outer membrane in many Gram-negative bacteria. Bacterial capsular polysaccharides are a diverse class of high molecular weight polysaccharides contributing to virulence of many human pathogens in the gut, respiratory tree, urinary tract, and other host tissues, by hiding cell-surface components that might otherwise elicit host immune response. This review highlights capsular polysaccharides that are structurally identical or similar to polysaccharides found in mammalian tissues, including polysialic acid and glycosaminoglycan capsules hyaluronan, heparosan, and chondroitin. Such non-immunogenic coatings render pathogens insensitive to certain immune responses, effectively increasing residence time in host tissues and enabling pathologically relevant population densities to be reached. Biosynthetic pathways and capsular involvement in immune system evasion are described providing a basis for potential therapies aimed at supplementing or replacing antibiotic treatment. PMID:24372337

  14. Immunogenic properties of Klebsiella pneumoniae type 2 capsular polysaccharide.

    PubMed Central

    Robert, A; Jouin, H; Fournier, J M

    1986-01-01

    The immunoprotective activity of Klebsiella pneumoniae K2 cell surface preparations and purified capsular polysaccharide was tested in mice. The 50% protective dose (PD50), expressed as capsular polysaccharide content, was 2 ng for cell surface preparations and 50 ng for purified capsular polysaccharide. Both preparations lost their immunoprotective activity after alkali treatment. Immune sera were raised in rabbits immunized with cell surface preparations. The precipitating and hemagglutinating capacity of these antisera was tested against either purified capsular polysaccharide or alkali-treated capsular polysaccharide. No difference was observed between the reactivity of the antisera against each antigen. The protective activity of these sera was tested on mice in passive transfer experiments, before and after absorption with either purified capsular polysaccharide or alkali-treated capsular polysaccharide. The sera lost their protective activity after absorption with purified capsular polysaccharide and after absorption with alkali-treated capsular polysaccharide. These experiments show that the difference in immunoprotective activity of cell surface preparations, purified capsular polysaccharide, and alkali-treated capsular polysaccharide is not due to a difference in their antigenic determinants. Cell surface preparations and purified capsular polysaccharide were fractionated by gel filtration on Sepharose 4B and by ultracentrifugation on cesium chloride density gradients. Three forms of capsular polysaccharide have been characterized. (i) A form of capsular polysaccharide with a very high protective activity (PD50 = 2 ng) that copurified with protein and lipopolysaccharide and was characterized by a low coefficient of distribution (Kd = 0.20) and a low density (1.5 to 1.6 g/cm3). (ii) A form of capsular polysaccharide with an intermediate protective activity (PD50 = 50 ng), contamined by less than 3% protein and 1% lipopolysaccharide, with a Kd of 0.35, and

  15. Structure of the capsular polysaccharide of Vibrio cholerae O139 synonym Bengal containing D-galactose 4,6-cyclophosphate.

    PubMed

    Knirel, Y A; Paredes, L; Jansson, P E; Weintraub, A; Widmalm, G; Albert, M J

    1995-09-01

    The capsular polysaccharide (CPS) of Vibrio cholerae O139 synonym Bengal, which is thought to carry determinants of O-specificity, was isolated by phenol/water extraction followed by delipidation of the contaminating lipopolysaccharide at pH 4.2 and gel-permeation chromatography. The CPS contained D-galactose, 3,6-dideoxy-L-xylo-hexose (colitose, Col), 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2,6-dideoxy-D-glucose (N-acetyl-D-quinovosamine, D-QuiNAc), D-galacturonic acid (D-GalA), and phosphate. The CPS was studied by NMR spectroscopy, methylation analysis, and selective degradations, including partial acid hydrolysis at pH 3.1 and dephosphorylation with aqueous 48% hydrofluoric acid, which both resulted in complete cleavage of Col. It was concluded that the CPS is built up of hexasaccharide repeating units containing inter alia D-galactose 4,6-cyclophosphate and having the following structure [structure: see text] These data basically confirm the structure of the V. cholerae CPS proposed on the basis of an NMR study [L. M. Preston et al. (1995) J. Bacteriol. 177, 835-838] and specify exactly the absolute configurations of the constituent monosaccharides and the position of the cyclic phosphate.

  16. Genetics of Capsular Polysaccharides and Cell Envelope (Glyco)lipids

    PubMed Central

    Daffé, Mamadou; Crick, Dean C.; Jackson, Mary

    2014-01-01

    This chapter summarizes what is currently known of the structures, physiological roles, involvement in pathogenicity and biogenesis of a variety of non-covalently bound cell envelope lipids and glycoconjugates of Mycobacterium tuberculosis and other Mycobacterium species. Topics addressed in this chapter include phospholipids; phosphatidylinositol mannosides; triglycerides; isoprenoids and related compounds (polyprenyl phosphate, menaquinones, carotenoids, non-carotenoid cyclic isoprenoids); acyltrehaloses (lipooligosaccharides, trehalose mono- and di-mycolates, sulfolipids, di- and poly-acyltrehaloses); mannosyl-beta-1-phosphomycoketides; glycopeptidolipids; phthiocerol dimycocerosates, para-hydroxybenzoic acids and phenolic glycolipids; mycobactins; mycolactones; and capsular polysaccharides. PMID:25485178

  17. Pneumococcus with the "6E" cps Locus Produces Serotype 6B Capsular Polysaccharide.

    PubMed

    Burton, Robert L; Geno, K Aaron; Saad, Jamil S; Nahm, Moon H

    2016-04-01

    Genetic studies of serogroup 6 isolates ofStreptococcus pneumoniaeidentified putative serotype 6E. Although its capsular polysaccharide structure has not been elucidated, putative serotype 6E is described in an increasing number of studies as a potentially new serotype. We show here that SPEC6B, which is widely used as a target strain for serotype 6B opsonophagocytosis assays, has the genetic features of the putative serotype 6E but produces capsular polysaccharide identical to 6B capsular polysaccharide as determined by one-dimensional (1D) and 2D nuclear magnetic resonance (NMR). Thus, putative serotype 6E is a mere genetic variant of serotype 6B. Also, SPEC6B is appropriate as a target strain for serotype 6B opsonophagocytosis assays. This example illustrates the difficulties of assigning new bacterial serotypes based on genetic findings alone.

  18. Serological, chemical, and structural analyses of the Escherichia coli cross-reactive capsular polysaccharides K13, K20, and K23.

    PubMed Central

    Vann, W F; Soderstrom, T; Egan, W; Tsui, F P; Schneerson, R; Orskov, I; Orskov, F

    1983-01-01

    The Escherichia coli K13, K20, and K23 capsular polysaccharide antigens are serologically related. All of these polysaccharides contain ribose and 2-keto-3-deoxyoctonate in equimolar quantities. The K13 and K20 polysaccharides are partially O-acetylated. A comparison of these polysaccharides after O-deacetylation, by nuclear magnetic resonance and permethylation analysis, showed that these polysaccharides contained the disaccharide repeat unit leads to)-beta-ribofuranosyl-(1 leads to 7)-beta-2-keto-3-deoxyoctonate. They differed in the presence and location of an acetyl moiety. The K13 polysaccharide was O-acetylated at C-4 of the 2-keto-3-deoxyoctonate. The K20 antigen was O-acetylated at C-5 of the ribose moiety. The K23 polymer was nonacetylated. The cross-reactivity of these antigens was demonstrated by tandem-crossed immunoelectrophoresis. Antibodies to K23 could be completely absorbed from OK K23 serum by K13, K20, and K23 antigenic extracts. The K13 and K20 antibodies could be completely absorbed from their respective antisera only by homologous antigenic extracts. Monoclonal antibodies were prepared against a protein conjugate of the K13 polysaccharide. Analyses of the reactions of these antibodies with the three polysaccharides suggest that the K13 polysaccharide has at least three antigenic sites, one of which is common to the K13, K20, and K23 polysaccharides. PMID:6187684

  19. Structure determination of Streptococcus suis serotype 9 capsular polysaccharide and assignment of functions of the cps locus genes involved in its biosynthesis.

    PubMed

    Vinogradov, Evgueny; Goyette-Desjardins, Guillaume; Okura, Masatoshi; Takamatsu, Daisuke; Gottschalk, Marcelo; Segura, Mariela

    2016-10-04

    Streptococcus suis serotype 9 is the most prevalent S. suis serotype in several European countries. In spite of its pathogenicity for pigs and increasing zoonotic potential, limited information is available on this serotype. Here we determined for the first time the chemical composition and structure of serotype 9 capsular polysaccharide (CPS), a major bacterial virulence factor and the antigen at the origin of S. suis classification into serotypes. Chemical and spectroscopic data gave the repeating unit sequence: [3)Glcol-6-P-3-[D-Gal(α1-2)]D-Gal(β1-3)D-Sug(β1-3)L-Rha(α1-)]n. Compared to previously characterized S. suis CPSs (serotypes 1, 1/2, 2 and 14), serotype 9 CPS does not contain sialic acid but contains a labile 4-keto sugar (2-acetamido-2,6-dideoxy-β-D-xylo-hexopyranos-4-ulose), one particular feature of this serotype. A correlation between S. suis serotype 9 CPS sequence and genes of this serotype cps locus encoding putative glycosyltransferases and polymerase responsible for the biosynthesis of the repeating unit was tentatively established. Knowledge of CPS structure and composition will contribute to better dissect the role of this bacterial component in the pathogenesis of S. suis serotype 9.

  20. Roles of Lipooligosaccharide and Capsular Polysaccharide in Antimicrobial Resistance and Natural Transformation of Campylobacter jejuni

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objectives: To investigate the roles of surface polysaccharides, such as capsular polysaccharide (CPS) and lipooligosaccharide (LOS), in modulating natural transformation and antimicrobial resistance in Campylobacter jejuni. Methods: A series of C. jejuni mutants, which are defective in either CPS ...

  1. Production of capsular polysaccharide of Streptococcus pneumoniae type 14 and its purification by affinity chromatography.

    PubMed

    Suárez, N; Fraguas, L F; Texeira, E; Massaldi, H; Batista-Viera, F; Ferreira, F

    2001-02-01

    We describe a rapid and efficient method for producing the capsular polysaccharide of Streptococcus pneumoniae by fermentation on tryptic soy broth and purification of this compound by using immobilized soybean lectin as an affinity adsorbent. In principle, the same strategy can be used to produce purified capsular polysaccharides from other streptococcal serotypes by selecting the appropriate lectin adsorbents.

  2. Production of Capsular Polysaccharide of Streptococcus pneumoniae Type 14 and Its Purification by Affinity Chromatography

    PubMed Central

    Suárez, Norma; Fraguas, Laura Franco; Texeira, Esther; Massaldi, Hugo; Batista-Viera, Francisco; Ferreira, Fernando

    2001-01-01

    We describe a rapid and efficient method for producing the capsular polysaccharide of Streptococcus pneumoniae by fermentation on tryptic soy broth and purification of this compound by using immobilized soybean lectin as an affinity adsorbent. In principle, the same strategy can be used to produce purified capsular polysaccharides from other streptococcal serotypes by selecting the appropriate lectin adsorbents. PMID:11157270

  3. Vaccination with peptide mimotopes produces antibodies recognizing bacterial capsular polysaccharides.

    PubMed

    Wu, Yang; Zhang, Qibo; Sales, Debra; Bianco, Albert Edward; Craig, Alister

    2010-09-07

    A phage display peptide library was screened using a panel of antibodies to the capsular polysaccharides of Streptococcus agalactiae and Neisseria meningitidis. Mimotopes NPDHPRVPTFMA (2-8), LIPFHKHPHHRG (3-2) and EQEIFTNITDRV (G3) showing the highest binding capacity and strongest ELISA reaction were selected for immunization experiments. These mimotopes were either synthesised as oligodeoxynucleotides for DNA immunization or MAP (multiple antigen peptide) for peptide immunization. Mimotope-DNA vaccination, particularly for G3, induced antibodies recognizing a number of target bacteria. This response was seen after the second boost injection and was significantly enhanced by the 3rd boost injection with a Th1-associated profile, which was dominated by IgG2a, followed by IgG1. Mimotope-MAP immunization also produced strong humoral immune responses to the bacteria. Antibodies from G3 DNA immunization reacted with the surface molecules of S. agalactiae, N. meningitidis and Escherichia coli K5 shown by indirect immunofluorescence staining, indicating a possible localization to the bacterial capsule. Antibodies produced both from DNA/MAP immunization reacted with purified bacterial capsular polysaccharides by ELISA and were of high avidity. We have further characterized peptide G3 by a 'tiling path' study to examine the effect of changing individual residues in the peptide in raising antibodies, which showed that the EIFTN motif in G3 was important in generating antibodies to several capsulated bacteria. We conclude that mimotope immunization with DNA or MAP potentially induces strong antibody responses against encapsulated bacteria. It is suggested that the antibody targets are polysaccharides, and these antibodies may cross react at least among closely related species of bacteria.

  4. Capsular Polysaccharide Expression in Commensal Streptococcus Species: Genetic and Antigenic Similarities to Streptococcus pneumoniae

    PubMed Central

    Skov Sørensen, Uffe B.; Yao, Kaihu; Yang, Yonghong; Tettelin, Hervé

    2016-01-01

    ABSTRACT Expression of a capsular polysaccharide is considered a hallmark of most invasive species of bacteria, including Streptococcus pneumoniae, in which the capsule is among the principal virulence factors and is the basis for successful vaccines. Consequently, it was previously assumed that capsule production distinguishes S. pneumoniae from closely related commensals of the mitis group streptococci. Based on antigenic and genetic analyses of 187 mitis group streptococci, including 90 recognized serotypes of S. pneumoniae, we demonstrated capsule production by the Wzy/Wzx pathway in 74% of 66 S. mitis strains and in virtually all tested strains of S. oralis (subspecies oralis, dentisani, and tigurinus) and S. infantis. Additional analyses of genomes of S. cristatus, S. parasanguinis, S. australis, S. sanguinis, S. gordonii, S. anginosus, S. intermedius, and S. constellatus revealed complete capsular biosynthesis (cps) loci in all strains tested. Truncated cps loci were detected in three strains of S. pseudopneumoniae, in 26% of S. mitis strains, and in a single S. oralis strain. The level of sequence identities of cps locus genes confirmed that the structural polymorphism of capsular polysaccharides in S. pneumoniae evolved by import of cps fragments from commensal Streptococcus species, resulting in a mosaic of genes of different origins. The demonstrated antigenic identity of at least eight of the numerous capsular polysaccharide structures expressed by commensal streptococci with recognized serotypes of S. pneumoniae raises concerns about potential misidentifications in addition to important questions concerning the consequences for vaccination and host-parasite relationships both for the commensals and for the pathogen. PMID:27935839

  5. Recombinant expression of Streptococcus pneumoniae capsular polysaccharides in Escherichia coli

    PubMed Central

    Kay, Emily J.; Yates, Laura E.; Terra, Vanessa S.; Cuccui, Jon; Wren, Brendan W.

    2016-01-01

    Currently, Streptococcus pneumoniae is responsible for over 14 million cases of pneumonia worldwide annually, and over 1 million deaths, the majority of them children. The major determinant for pathogenesis is a polysaccharide capsule that is variable and is used to distinguish strains based on their serotype. The capsule forms the basis of the pneumococcal polysaccharide vaccine (PPV23) that contains purified capsular polysaccharide from 23 serotypes, and the pneumococcal conjugate vaccine (PCV13), containing 13 common serotypes conjugated to CRM197 (mutant diphtheria toxin). Purified capsule from S. pneumoniae is required for pneumococcal conjugate vaccine production, and costs can be prohibitively high, limiting accessibility of the vaccine in low-income countries. In this study, we demonstrate the recombinant expression of the capsule-encoding locus from four different serotypes of S. pneumoniae within Escherichia coli. Furthermore, we attempt to identify the minimum set of genes necessary to reliably and efficiently express these capsules heterologously. These E. coli strains could be used to produce a supply of S. pneumoniae serotype-specific capsules without the need to culture pathogenic bacteria. Additionally, these strains could be applied to synthetic glycobiological applications: recombinant vaccine production using E. coli outer membrane vesicles or coupling to proteins using protein glycan coupling technology. PMID:27110302

  6. O-METHYL PHOSPHORAMIDATE MODIFICATIONS ON THE CAPSULAR POLYSACCHARIDE OF CAMPYLOBACTER JEJUNI ARE INVOLVED IN SERUM RESISTANCE, INFECTION, AND INSECTICIDAL ACTIVITY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Campylobacter jejuni is the most commonly reported cause of bacterial foodborne illness in North America. C. jejuni decorates its surface polysaccharides with a variety of variable phosphorylated structures, including O-methyl phosphoramidate (MeOPN) modifications on the capsular polysaccharide. Alt...

  7. Overproduction of Type 8 Capsular Polysaccharide Augments Staphylococcus aureus Virulence

    PubMed Central

    Luong, Thanh T.; Lee, Chia Y.

    2002-01-01

    Type 8 capsular polysaccharide (CP8) is the most prevalent capsule type in clinical isolates of Staphylococcus aureus. However, its role in virulence has not been clearly defined. CP8 strains such as strain Becker produce a small amount of capsule on their surface in vitro. In contrast, CP1 strains such as strain M produce a large amount of capsule, which has been shown to be an important antiphagocytic virulence factor. The cap8 and cap1 operons, required for the synthesis of CP8 and CP1, respectively, have been cloned and sequenced. To test whether CP8 contributes to the pathogenesis of S. aureus, we replaced the weak native promoter of the cap8 operon in strain Becker with the strong constitutive promoter of the cap1 operon of strain M. The resultant strain, CYL770, synthesized cap8-specific mRNA at a level about sevenfold higher than that in the parent strain. Remarkably, the CYL770 strain produced about 80-fold more CP8. In a mouse infection model of bacteremia, the CP8-overproducing strain persisted longer in the bloodstream, the liver, and the spleen in mice than the parent strain. In addition, strain CYL770 was more resistant to ospsonophagocytosis in vitro by human polymorphonuclear leukocytes. These results indicate that CP8 is an antiphagocytic virulence factor of S. aureus. PMID:12065477

  8. Maternal group B streptococcal immunization: capsular polysaccharide (CPS)-based vaccines and their implications on prevention.

    PubMed

    Palmeiro, Jussara K; De Carvalho, Newton S; Botelho, Ana C N; Fracalanzza, Sérgio E L; Madeira, Humberto M F; Dalla-Costa, Libera M

    2011-05-12

    Group B streptococcal (GBS) capsular polysaccharide (CPS)-based conjugate vaccine, which includes types Ia, Ib, II, III, and V, could potentially prevent neonatal, pediatric, adult, and pregnancy-associated diseases. However, since GBS CPS types included in that vaccine are prevalent serotypes found in North America and Europe, it may not provide the necessary protection for individuals in countries in which other capsular types have been found.

  9. Evidence for Branching in Cryptococcal Capsular Polysaccharides and Consequences on its Biological Activity

    PubMed Central

    Cordero, Radames J.B.; Frases, Susana; Guimaräes, Allan J.; Rivera, Johanna; Casadevall, Arturo

    2011-01-01

    SUMMARY The encapsulated fungus Cryptococcus neoformans is a common cause of life-threatening disease in immunocompromised individuals. Its major virulence determinant is the polysaccharide (PS) capsule. An unsolved problem in cryptococcal biology is whether the PSs composing the capsule are linear or complex branched polymers, as well as the implications of this structural composition in pathogenesis. In this study we approached the problem by combining static and dynamic light scattering, viscosity analysis, and high-resolution microscopy and correlated the findings with biological properties. Analysis of the dependence of capsular PS molecular mass and the radius of gyration provided strong evidence against a simple linear PS configuration. Shape factors calculated from light scattering measurements in solution revealed values consistent with polymer branching. Furthermore, viscosity measurements provided complementary evidence for structural branching. Electron microscopy showed PS spherical-like structures similar to other branched PS. Finally, we show that the capacity of capsular PS to interfere in complement-mediated phagocytosis, inhibit nitric oxide production by macrophage-like cells, protect against reactive oxygen species, antibody reactivity and half-life in serum were influenced by the degree of branching, providing evidence for the notion that PS branching is an important parameter in determining the biological activity of C. neoformans PS. PMID:21208301

  10. Evidence for branching in cryptococcal capsular polysaccharides and consequences on its biological activity.

    PubMed

    Cordero, Radames J B; Frases, Susana; Guimaräes, Allan J; Rivera, Johanna; Casadevall, Arturo

    2011-02-01

    The encapsulated fungus Cryptococcus neoformans is a common cause of life-threatening disease in immunocompromised individuals. Its major virulence determinant is the polysaccharide (PS) capsule. An unsolved problem in cryptococcal biology is whether the PSs composing the capsule are linear or complex branched polymers, as well as the implications of this structural composition in pathogenesis. In this study we approached the problem by combining static and dynamic light scattering, viscosity analysis, and high-resolution microscopy and correlated the findings with biological properties. Analysis of the dependence of capsular PS molecular mass and the radius of gyration provided strong evidence against a simple linear PS configuration. Shape factors calculated from light scattering measurements in solution revealed values consistent with polymer branching. Furthermore, viscosity measurements provided complementary evidence for structural branching. Electron microscopy showed PS spherical-like structures similar to other branched PS. Finally, we show that the capacity of capsular PS to interfere in complement-mediated phagocytosis, inhibit nitric oxide production by macrophage-like cells, protect against reactive oxygen species, antibody reactivity and half-life in serum were influenced by the degree of branching, providing evidence for the notion that PS branching is an important parameter in determining the biological activity of C. neoformans PS.

  11. Acinetobacter baumannii K27 and K44 capsular polysaccharides have the same K unit but different structures due to the presence of distinct wzy genes in otherwise closely related K gene clusters.

    PubMed

    Shashkov, Alexander S; Kenyon, Johanna J; Senchenkova, Sof'ya N; Shneider, Mikhail M; Popova, Anastasiya V; Arbatsky, Nikolay P; Miroshnikov, Konstantin A; Volozhantsev, Nikolay V; Hall, Ruth M; Knirel, Yuriy A

    2016-05-01

    Capsular polysaccharides (CPSs), from Acinetobacter baumannii isolates 1432, 4190 and NIPH 70, which have related gene content at the K locus, were examined, and the chemical structures established using 2D(1)H and(13)C NMR spectroscopy. The three isolates produce the same pentasaccharide repeat unit, which consists of 5-N-acetyl-7-N-[(S)-3-hydroxybutanoyl] (major) or 5,7-di-N-acetyl (minor) derivatives of 5,7-diamino-3,5,7,9-tetradeoxy-D-glycero-D-galacto-non-2-ulosonic (legionaminic) acid (Leg5Ac7R), D-galactose, N-acetyl-D-galactosamine and N-acetyl-D-glucosamine. However, the linkage between repeat units in NIPH 70 was different to that in 1432 and 4190, and this significantly alters the CPS structure. The KL27 gene cluster in 4190 and KL44 gene cluster in NIPH 70 are organized identically and contain lga genes for Leg5Ac7R synthesis, genes for the synthesis of the common sugars, as well as anitrA2 initiating transferase and four glycosyltransferases genes. They share high-level nucleotide sequence identity for corresponding genes, but differ in the wzy gene encoding the Wzy polymerase. The Wzy proteins, which have different lengths and share no similarity, would form the unrelated linkages in the K27 and K44 structures. The linkages formed by the four shared glycosyltransferases were predicted by comparison with gene clusters that synthesize related structures. These findings unambiguously identify the linkages formed by WzyK27 and WzyK44, and show that the presence of different wzy genes in otherwise closely related K gene clusters changes the structure of the CPS. This may affect its capacity as a protective barrier for A. baumannii.

  12. Latex agglutination: diagnose the early cryptococcus neoformans test of capsular polysaccharide antigen.

    PubMed

    Wang, Huanrong; Yuan, Xueqian; Zhang, Lifeng

    2015-01-01

    This paper aims to discuss the early diagnosis value of latex agglutination test in Cryptococcal meningitis. The cerebrospinal fluid (CSF) of 112 patients with definite Cryptococcal meningitis and 26 patients with tubercular meningitis and virus meningitis were collected, latex agglutination test is adopted to detect Cryptococcal capsular polysaccharide antigen. Then it was compared with fungal culture and direct microscopy method for evaluating the sensitivity and specificity of the diagnosis. The sensitivity of three methods including latex agglutination test, fungal culture and direct microscopy was 91.1%,69.6% and 73.2% respectively. The specificity of latex agglutination test was 96.0%, 100% and 100% respectively. That latex agglutination test to detect Cryptococcal capsular polysaccharide antigen could be taken as the early diagnostic method of Cryptococcus neoformans meningitis.

  13. Capsular polysaccharide of Erysipelothrix rhusiopathiae, the causative agent of swine erysipelas, and its modification with phosphorylcholine.

    PubMed

    Shi, Fang; Harada, Tomoyuki; Ogawa, Yohsuke; Ono, Hiroshi; Ohnishi-Kameyama, Mayumi; Miyamoto, Toru; Eguchi, Masahiro; Shimoji, Yoshihiro

    2012-11-01

    The capsule has been implicated in the virulence of the swine pathogen Erysipelothrix rhusiopathiae, a rod-shaped, intracellular Gram-positive bacterium that has a unique phylogenetic position in the phylum Firmicutes and is a close relative of Mollicutes (mycoplasma species). In this study, we analyzed the genetic locus and composition of the capsular polysaccharide (CPS) of the Fujisawa strain of E. rhusiopathiae. Genome analysis of the Fujisawa strain revealed that the genetic locus for capsular polysaccharide synthesis (cps) is located next to an lic operon, which is involved in the incorporation and expression of phosphorylcholine (PCho). Reverse transcription-PCR analysis showed that cps and lic are transcribed as a single mRNA, indicating that the loci form an operon. Using the cell surface antigen-specific monoclonal antibody (MAb) ER21 as a probe, the capsular materials were isolated from the Fujisawa strain by hot water extraction and treatment with DNase, RNase, pronase, and N-acetylmuramidase SG, followed by anion-exchange and gel filtration chromatography. The materials were then analyzed by high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance (NMR) spectroscopy. The CPS of E. rhusiopathiae is heterogeneous and consists of the major monosaccharides galacturonic acid, galactose, mannose, glucose, arabinose, xylose, and N-acetylglucosamine and some minor monosaccharides containing ribose, rhamnose, and N-acetylgalactosamine. In addition, the capsule is modified by PCho, which comigrates with the capsular materials, as determined by Western immunoblotting, and colocalizes on the cell surface, as determined by immunogold electron microscopy. Virulence testing of PCho-defective mutants in mice demonstrated that PCho is critical for the virulence of this organism.

  14. Capsular Polysaccharide of Erysipelothrix rhusiopathiae, the Causative Agent of Swine Erysipelas, and Its Modification with Phosphorylcholine

    PubMed Central

    Shi, Fang; Harada, Tomoyuki; Ogawa, Yohsuke; Ono, Hiroshi; Ohnishi-Kameyama, Mayumi; Miyamoto, Toru; Eguchi, Masahiro

    2012-01-01

    The capsule has been implicated in the virulence of the swine pathogen Erysipelothrix rhusiopathiae, a rod-shaped, intracellular Gram-positive bacterium that has a unique phylogenetic position in the phylum Firmicutes and is a close relative of Mollicutes (mycoplasma species). In this study, we analyzed the genetic locus and composition of the capsular polysaccharide (CPS) of the Fujisawa strain of E. rhusiopathiae. Genome analysis of the Fujisawa strain revealed that the genetic locus for capsular polysaccharide synthesis (cps) is located next to an lic operon, which is involved in the incorporation and expression of phosphorylcholine (PCho). Reverse transcription-PCR analysis showed that cps and lic are transcribed as a single mRNA, indicating that the loci form an operon. Using the cell surface antigen-specific monoclonal antibody (MAb) ER21 as a probe, the capsular materials were isolated from the Fujisawa strain by hot water extraction and treatment with DNase, RNase, pronase, and N-acetylmuramidase SG, followed by anion-exchange and gel filtration chromatography. The materials were then analyzed by high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance (NMR) spectroscopy. The CPS of E. rhusiopathiae is heterogeneous and consists of the major monosaccharides galacturonic acid, galactose, mannose, glucose, arabinose, xylose, and N-acetylglucosamine and some minor monosaccharides containing ribose, rhamnose, and N-acetylgalactosamine. In addition, the capsule is modified by PCho, which comigrates with the capsular materials, as determined by Western immunoblotting, and colocalizes on the cell surface, as determined by immunogold electron microscopy. Virulence testing of PCho-defective mutants in mice demonstrated that PCho is critical for the virulence of this organism. PMID:22949554

  15. Solution conformation and flexibility of capsular polysaccharides from Neisseria meningitidis and glycoconjugates with the tetanus toxoid protein

    NASA Astrophysics Data System (ADS)

    Abdelhameed, Ali Saber; Morris, Gordon A.; Almutairi, Fahad; Adams, Gary G.; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E.

    2016-10-01

    The structural integrity of meningococcal native, micro-fluidized and activated capsular polysaccharides and their glycoconjugates – in the form most relevant to their potential use as vaccines (dilute solution) - have been investigated with respect to their homogeneity, conformation and flexibility. Sedimentation velocity analysis showed that the polysaccharide size distributions were generally bimodal with some evidence for higher molar mass forms at higher concentration. Weight average molar masses Mw where lower for activated polysaccharides. Conjugation with tetanus toxoid protein however greatly increased the molar mass and polydispersity of the final conjugates. Glycoconjugates had an approximately unimodal log-normal but broad and large molar mass profiles, confirmed by sedimentation equilibrium “SEDFIT MSTAR” analysis. Conformation analysis using HYDFIT (which globally combines sedimentation and viscosity data), “Conformation Zoning” and Wales-van Holde approaches showed a high degree of flexibility – at least as great as the unconjugated polysaccharides, and very different from the tetanus toxoid (TT) protein used for the conjugation. As with the recently published finding for Hib-TT complexes, it is the carbohydrate component that dictates the solution behaviour of these glycoconjugates, although the lower intrinsic viscosities suggest some degree of compaction of the carbohydrate chains around the protein.

  16. Solution conformation and flexibility of capsular polysaccharides from Neisseria meningitidis and glycoconjugates with the tetanus toxoid protein

    PubMed Central

    Abdelhameed, Ali Saber; Morris, Gordon A.; Almutairi, Fahad; Adams, Gary G.; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E.

    2016-01-01

    The structural integrity of meningococcal native, micro-fluidized and activated capsular polysaccharides and their glycoconjugates – in the form most relevant to their potential use as vaccines (dilute solution) - have been investigated with respect to their homogeneity, conformation and flexibility. Sedimentation velocity analysis showed that the polysaccharide size distributions were generally bimodal with some evidence for higher molar mass forms at higher concentration. Weight average molar masses Mw where lower for activated polysaccharides. Conjugation with tetanus toxoid protein however greatly increased the molar mass and polydispersity of the final conjugates. Glycoconjugates had an approximately unimodal log-normal but broad and large molar mass profiles, confirmed by sedimentation equilibrium “SEDFIT MSTAR” analysis. Conformation analysis using HYDFIT (which globally combines sedimentation and viscosity data), “Conformation Zoning” and Wales-van Holde approaches showed a high degree of flexibility – at least as great as the unconjugated polysaccharides, and very different from the tetanus toxoid (TT) protein used for the conjugation. As with the recently published finding for Hib-TT complexes, it is the carbohydrate component that dictates the solution behaviour of these glycoconjugates, although the lower intrinsic viscosities suggest some degree of compaction of the carbohydrate chains around the protein. PMID:27782149

  17. In vivo Distribution and Clearance of Purified Capsular Polysaccharide from Burkholderia pseudomallei in a Murine Model

    PubMed Central

    Nualnoi, Teerapat; Kirosingh, Adam; Pandit, Sujata G.; Thorkildson, Peter; Brett, Paul J.; Burtnick, Mary N.; AuCoin, David P.

    2016-01-01

    Burkholderia pseudomallei is the causative agent of melioidosis, a severe infection prominent in northern Australia and Southeast Asia. The “gold standard” for melioidosis diagnosis is bacterial isolation, which takes several days to complete. The resulting delay in diagnosis leads to delayed treatments, which could result in death. In an attempt to develop better methods for early diagnosis of melioidosis, B. pseudomallei capsular polysaccharide (CPS) was identified as an important diagnostic biomarker. A rapid lateral flow immunoassay utilizing CPS-specific monoclonal antibody was developed and tested in endemic regions worldwide. However, the in vivo fate and clearance of CPS has never been thoroughly investigated. Here, we injected mice with purified CPS intravenously and determined CPS concentrations in serum, urine, and major organs at various intervals. The results indicate that CPS is predominantly eliminated through urine and no CPS accumulation occurs in the major organs. Immunoblot analysis demonstrated that intact CPS was excreted through urine. To understand how a large molecule like CPS was eliminated without degradation, a 3-dimenational structure of CPS was modeled. The predicted CPS structure has a rod-like shape with a small diameter that could allow it to flow through the glomerulus of the kidney. CPS clearance was determined using exponential decay models and the corrected Akaike Information Criterion. The results show that CPS has a relatively short serum half-life of 2.9 to 4.4 hours. Therefore, the presence of CPS in the serum and/or urine suggests active melioidosis infection and provides a marker to monitor treatment of melioidosis. PMID:27941991

  18. In vivo Distribution and Clearance of Purified Capsular Polysaccharide from Burkholderia pseudomallei in a Murine Model.

    PubMed

    Nualnoi, Teerapat; Kirosingh, Adam; Pandit, Sujata G; Thorkildson, Peter; Brett, Paul J; Burtnick, Mary N; AuCoin, David P

    2016-12-01

    Burkholderia pseudomallei is the causative agent of melioidosis, a severe infection prominent in northern Australia and Southeast Asia. The "gold standard" for melioidosis diagnosis is bacterial isolation, which takes several days to complete. The resulting delay in diagnosis leads to delayed treatments, which could result in death. In an attempt to develop better methods for early diagnosis of melioidosis, B. pseudomallei capsular polysaccharide (CPS) was identified as an important diagnostic biomarker. A rapid lateral flow immunoassay utilizing CPS-specific monoclonal antibody was developed and tested in endemic regions worldwide. However, the in vivo fate and clearance of CPS has never been thoroughly investigated. Here, we injected mice with purified CPS intravenously and determined CPS concentrations in serum, urine, and major organs at various intervals. The results indicate that CPS is predominantly eliminated through urine and no CPS accumulation occurs in the major organs. Immunoblot analysis demonstrated that intact CPS was excreted through urine. To understand how a large molecule like CPS was eliminated without degradation, a 3-dimenational structure of CPS was modeled. The predicted CPS structure has a rod-like shape with a small diameter that could allow it to flow through the glomerulus of the kidney. CPS clearance was determined using exponential decay models and the corrected Akaike Information Criterion. The results show that CPS has a relatively short serum half-life of 2.9 to 4.4 hours. Therefore, the presence of CPS in the serum and/or urine suggests active melioidosis infection and provides a marker to monitor treatment of melioidosis.

  19. CUTANEOUS REACTIONS IN RABBITS TO THE TYPE-SPECIFIC CAPSULAR POLYSACCHARIDES OF PNEUMOCOCCUS

    PubMed Central

    Francis, Thomas; Tillett, William S.

    1931-01-01

    The injection of the type-specific capsular polysaccharides of Pneumococcus Types I, II and III into the skin of rabbits, actively or passively immunized to one of these types of Pneumococcus, elicits a type-specific cutaneous reaction. The form of reaction resembles that described by Arthus. The reaction is produced only when type-specific precipitins for the homologous polysaccharide are demonstrable in the blood of the rabbit. In 84 per cent of actively immunized rabbits, the serum of which contained type-specific precipitins, a reaction was elicited. A positive result was obtained in 100 per cent of rabbits passively immunized with antipneumococcus horse serum whereas, attempts passively to transfer reactivity from immune rabbit to normal rabbit were unsuccessful. The recipients, in the latter group, possessed no demonstrable circulating type-specific precipitins. The reaction produced by specific capsular carbohydrates is always associated with a well grounded type-specific immunity. A brief summary of the relation of hypersensitiveness and immunity to pneumococcus is given. PMID:19869942

  20. Expression of crossreactive idiotypes by human antibodies specific for the capsular polysaccharide of Hemophilus influenzae B.

    PubMed Central

    Lucas, A H

    1988-01-01

    Human antibodies specific, for polyribosyl-ribitol-phosphate (PRP), the capsular polysaccharide of Hemophilus influenzae b, were studied using idiotypic analysis. Antisera were prepared against purified F(ab')2 anti-PRP from two unrelated adults, H.H. and P.T. After repeated absorption with IgG myeloma proteins and with PRP-absorbed normal human Ig and donor Ig, anti-idiotypic (anti-Id) sera were obtained that specifically reacted with anti-PRP antibodies. Anti-IdHH and anti-IdPT reciprocally crossreacted with H.H. and P.T. anti-PRP antibodies and F(ab')2 fragments, and also reacted with the serum anti-PRP antibodies from three additional adults unrelated to P.T. and H.H. Both anti-Id sera partially inhibited anti-PRP paratopes but not anti-tetanus toxoid paratopes. PRP did not inhibit anti-Id recognition of shared or crossreactive idiotypic (CRI) determinants. Naturally occurring and PRP immunization-induced anti-PRP antibodies expressed CRI. While CRI titer increased after immunization, the increase was usually less than the rise in total anti-PRP antibody. Quantitative differences in CRI expression were also apparent between natural and immunization-induced H.H. and P.T. anti-PRP antibodies as shown by their differential inhibitability by anti-Id. Our data demonstrate that anti-PRP antibodies from five unrelated adults express CRI determinants that are probably distant from the PRP combining site. Naturally occurring and immunization-induced anti-PRP antibodies share CRI and therefore appear to be clonally related, although immunization apparently induces the expression CRI-negative antibodies as well. These results, taken with previous studies showing restricted and identical anti-PRP isoelectric focusing spectrotypes in unrelated adults, suggest that some PRP-specific V domains are structurally conserved and probably germ-line encoded. PMID:3257499

  1. HPAEC-PAD method for the analysis of alkaline hydrolyzates of Haemophilus influenzae type b capsular polysaccharide.

    PubMed

    de Haan, Alex; van der Put, Robert M F; Beurret, Michel

    2013-09-01

    A gradient method has been devised for the rapid analysis of alkaline hydrolyzates of Haemophilus influenzae type b (Hib) capsular polysaccharide-based vaccines by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). As compared with published procedures, peak shape and sensitivity were significantly improved with this approach, analysis time was short and there was little interference from impurities. The limits of detection and quantification were established with a purified reference polysaccharide. We propose this method as a practical alternative for the analysis of minute amounts of Hib polysaccharide, which can be lower than with the conventional approaches.

  2. The Vi capsular polysaccharide enables Salmonella enterica serovar typhi to evade microbe-guided neutrophil chemotaxis.

    PubMed

    Wangdi, Tamding; Lee, Cheng-Yuk; Spees, Alanna M; Yu, Chenzhou; Kingsbury, Dawn D; Winter, Sebastian E; Hastey, Christine J; Wilson, R Paul; Heinrich, Volkmar; Bäumler, Andreas J

    2014-08-01

    Salmonella enterica serovar Typhi (S. Typhi) causes typhoid fever, a disseminated infection, while the closely related pathogen S. enterica serovar Typhimurium (S. Typhimurium) is associated with a localized gastroenteritis in humans. Here we investigated whether both pathogens differ in the chemotactic response they induce in neutrophils using a single-cell experimental approach. Surprisingly, neutrophils extended chemotactic pseudopodia toward Escherichia coli and S. Typhimurium, but not toward S. Typhi. Bacterial-guided chemotaxis was dependent on the presence of complement component 5a (C5a) and C5a receptor (C5aR). Deletion of S. Typhi capsule biosynthesis genes markedly enhanced the chemotactic response of neutrophils in vitro. Furthermore, deletion of capsule biosynthesis genes heightened the association of S. Typhi with neutrophils in vivo through a C5aR-dependent mechanism. Collectively, these data suggest that expression of the virulence-associated (Vi) capsular polysaccharide of S. Typhi obstructs bacterial-guided neutrophil chemotaxis.

  3. A peptide mimotope of type 8 pneumococcal capsular polysaccharide induces a protective immune response in mice.

    PubMed

    Buchwald, Ulrike K; Lees, Andrew; Steinitz, Michael; Pirofski, Liise-Anne

    2005-01-01

    Increasing antibiotic resistance and a rising patient population at risk for infection due to impaired immunity underscore the importance of vaccination against pneumococci. However, available capsular polysaccharide vaccines are often poorly immunogenic in patients at risk for pneumococcal disease. The goal of this study was to explore the potential of peptide mimotopes to function as alternative vaccine antigens to elicit a type-specific antibody response to pneumococci. We used a human monoclonal immunoglobulin A (IgA) antibody (NAD) to type 8 Streptococcus pneumoniae capsular polysaccharide (type 8 PS) to screen a phage display library, and the phage PUB1 displaying the peptide FHLPYNHNWFAL was selected after three rounds of biopanning. Inhibition studies with phage-displayed peptide or the peptide PUB1 and type 8 PS showed that PUB1 is a mimetic of type 8 PS. PUB1 conjugated to tetanus toxoid (PUB1-TT) induced a type 8 PS-specific antibody response in BALB/c mice, further defining it as a mimotope of type 8 PS. The administration of immune sera obtained from PUB1-TT-immunized mice earlier (days 14 and 21) and later (days 87 and 100) after primary and reimmunization resulted in a highly significant prolongation of the survival of naive mice after pneumococcal challenge compared to controls. The survival of PUB1-TT-immunized mice was also prolonged after pneumococcal challenge nearly 4 months after primary immunization. The efficacy of PUB1-TT-induced immune sera provides proof of principle that a mimotope-induced antibody response can protect against pneumococci and suggests that peptide mimotopes selected by type-specific human antibodies could hold promise as immunogens for pneumococci.

  4. Molecular Characterization of Type-Specific Capsular Polysaccharide Biosynthesis Genes of Streptococcus agalactiae Type Ia

    PubMed Central

    Yamamoto, Shin; Miyake, Katsuhide; Koike, Yoichi; Watanabe, Masaki; Machida, Yuichi; Ohta, Michio; Iijima, Shinji

    1999-01-01

    The type-specific capsular polysaccharide (CP) of a group B streptococcus, Streptococcus agalactiae type Ia, is a high-molecular-weight polymer consisting of the pentasaccharide repeating unit 4)-[α-d-NeupNAc-(2→3)-β-d-Galp-(1→4)-β-d-GlcpNAc-(1→3)]-β-d-Galp-(1→4)-β-d-Glcp-(1. Here, cloning, sequencing, and transcription of the type Ia-specific capsular polysaccharide synthesis (cps) genes and functional analysis of these gene products are described. A 26-kb DNA fragment containing 18 complete open reading frames (ORFs) was cloned. These ORFs were designated cpsIaA to cpsIaL, neu (neuraminic acid synthesis gene) A to D, orf1 and ung (uracil DNA glycosylase). The cps gene products of S. agalactiae type Ia were homologous to proteins involved in CP synthesis of S. agalactiae type III and S. pneumoniae serotype 14. Unlike the cps gene cluster of S. pneumoniae serotype 14, transcription of this operon may start from cpsIaA, cpsIaE, and orf1 because putative promoter sequences were found in front of these genes. Northern hybridization, reverse transcription-PCR, and primer extension analyses supported this hypothesis. DNA sequence analysis showed that there were two transcriptional terminators in the 3′ end of this operon (downstream of orf1 and ung). The functions of CpsIaE, CpsIaG, CpsIaI, and CpsIaJ were examined by glycosyltransferase assay by using the gene products expressed in Escherichia coli JM109 harboring plasmids containing various S. agalactiae type Ia cps gene fragments. Enzyme assays suggested that the gene products of cpsIaE, cpsIaG, cpsIaI, and cpsIaJ are putative glucosyltransferase, β-1,4-galactosyltransferase, β-1,3-N-acetylglucosaminyltransferase, and β-1,4-galactosyltransferase, respectively. PMID:10464185

  5. NMR and molecular dynamics studies of the conformational epitope of the type III group B Streptococcus capsular polysaccharide and derivatives.

    PubMed

    Brisson, J R; Uhrinova, S; Woods, R J; van der Zwan, M; Jarrell, H C; Paoletti, L C; Kasper, D L; Jennings, H J

    1997-03-18

    The conformational epitope of the type III group B Streptococcus capsular polysaccharide (GBSP III) exhibits unique properties which can be ascribed to the presence of sialic acid in its structure and the requirement for an extended binding site. By means of NMR and molecular dynamics studies on GBSP III and its fragments, the extended epitope of GBSP III was further defined. The influence of sialic acid on the conformational properties of GBSP III was examined by performing conformational analysis on desialylated GBSP III, which is identical to the polysaccharide of Streptococcus pneumoniae type 14, and also on oxidized and reduced GBSP III. Conformational changes were gauged by 1H and 13C chemical shift analysis, NOE, 1D selective TOCSY-NOESY experiments, J(HH) and J(CH) variations, and NOE of OH resonances. Changes in mobility were examined by 13C T1 and T2 measurements. Unrestrained molecular dynamics simulations with explicit water using the AMBER force field and the GLYCAM parameter set were used to assess static and dynamic conformational models, simulate the observable NMR parameters and calculate helical parameters. GBSP III was found to be capable of forming extended helices. Hence, the length dependence of the conformational epitope could be explained by its location on extended helices within the random coil structure of GBSP III. The interaction of sialic acid with the backbone of the PS was also found to be important in defining the conformational epitope of GBSP III.

  6. A glycoconjugate of Haemophilus influenzae Type b capsular polysaccharide with tetanus toxoid protein: hydrodynamic properties mainly influenced by the carbohydrate

    PubMed Central

    Abdelhameed, Ali Saber; Adams, Gary G.; Morris, Gordon A.; Almutairi, Fahad M.; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E.

    2016-01-01

    Three important physical properties which may affect the performance of glycoconjugate vaccines against serious disease are molar mass (molecular weight), heterogeneity (polydispersity), and conformational flexibility in solution. The dilute solution behaviour of native and activated capsular polyribosylribitol (PRP) polysaccharides extracted from Haemophilus influenzae type b (Hib), and the corresponding glycoconjugate made by conjugating this with the tetanus toxoid (TT) protein have been characterized and compared using a combination of sedimentation equilibrium and sedimentation velocity in the analytical ultracentrifuge with viscometry. The weight average molar mass of the activated material was considerably reduced (Mw ~ 0.24 × 106 g.mol−1) compared to the native (Mw ~ 1.2 × 106 g.mol−1). Conjugation with the TT protein yielded large polydisperse structures (of Mw ~ 7.4 × 106 g.mol−1), but which retained the high degree of flexibility of the native and activated polysaccharide, with frictional ratio, intrinsic viscosity, sedimentation conformation zoning behaviour and persistence length all commensurate with highly flexible coil behaviour and unlike the previously characterised tetanus toxoid protein (slightly extended and hydrodynamically compact structure with an aspect ratio of ~3). This non-protein like behaviour clearly indicates that it is the carbohydrate component which mainly influences the physical behaviour of the glycoconjugate in solution. PMID:26915577

  7. A glycoconjugate of Haemophilus influenzae Type b capsular polysaccharide with tetanus toxoid protein: hydrodynamic properties mainly influenced by the carbohydrate.

    PubMed

    Abdelhameed, Ali Saber; Adams, Gary G; Morris, Gordon A; Almutairi, Fahad M; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E

    2016-02-26

    Three important physical properties which may affect the performance of glycoconjugate vaccines against serious disease are molar mass (molecular weight), heterogeneity (polydispersity), and conformational flexibility in solution. The dilute solution behaviour of native and activated capsular polyribosylribitol (PRP) polysaccharides extracted from Haemophilus influenzae type b (Hib), and the corresponding glycoconjugate made by conjugating this with the tetanus toxoid (TT) protein have been characterized and compared using a combination of sedimentation equilibrium and sedimentation velocity in the analytical ultracentrifuge with viscometry. The weight average molar mass of the activated material was considerably reduced (Mw ~ 0.24 × 10(6) g.mol(-1)) compared to the native (Mw ~ 1.2 × 10(6) g.mol(-1)). Conjugation with the TT protein yielded large polydisperse structures (of Mw ~ 7.4 × 10(6) g.mol(-1)), but which retained the high degree of flexibility of the native and activated polysaccharide, with frictional ratio, intrinsic viscosity, sedimentation conformation zoning behaviour and persistence length all commensurate with highly flexible coil behaviour and unlike the previously characterised tetanus toxoid protein (slightly extended and hydrodynamically compact structure with an aspect ratio of ~3). This non-protein like behaviour clearly indicates that it is the carbohydrate component which mainly influences the physical behaviour of the glycoconjugate in solution.

  8. Isolation of a Bacteriophage Specific for a New Capsular Type of Klebsiella pneumoniae and Characterization of Its Polysaccharide Depolymerase

    PubMed Central

    Hsu, Chun-Ru; Lin, Tzu-Lung; Pan, Yi-Jiun; Hsieh, Pei-Fang; Wang, Jin-Town

    2013-01-01

    Background Klebsiella pneumoniae is one of the major pathogens causing hospital-acquired multidrug-resistant infections. The capsular polysaccharide (CPS) is an important virulence factor of K. pneumoniae. With 78 capsular types discovered thus far, an association between capsular type and the pathogenicity of K. pneumoniae has been observed. Methodology/Principal Findings To investigate an initially non-typeable K. pneumoniae UTI isolate NTUH-K1790N, the cps gene region was sequenced. By NTUH-K1790N cps-PCR genotyping, serotyping and determination using a newly isolated capsular type-specific bacteriophage, we found that NTUH-K1790N and three other isolates Ca0507, Ca0421 and C1975 possessed a new capsular type, which we named KN2. Analysis of a KN2 CPS− mutant confirmed the role of capsule as the target recognized by the antiserum and the phage. A newly described lytic phage specific for KN2 K. pneumoniae, named 0507-KN2-1, was isolated and characterized using transmission electron microscopy. Whole-genome sequencing of 0507-KN2-1 revealed a 159 991 bp double-stranded DNA genome with a G+C content of 46.7% and at least 154 open reading frames. Based on its morphological and genomic characteristics, 0507-KN2-1 was classified as a member of the Myoviridae phage family. Further analysis of this phage revealed a 3738-bp gene encoding a putative polysaccharide depolymerase. A recombinant form of this protein was produced and assayed to confirm its enzymatic activity and specificity to KN2 capsular polysaccharides. KN2 K. pneumoniae strains exhibited greater sensitivity to this depolymerase than these did to the cognate phage, as determined by spot analysis. Conclusions/Significance Here we report that a group of clinical strains possess a novel Klebsiella capsular type. We identified a KN2-specific phage and its polysaccharide depolymerase, which could be used for efficient capsular typing. The lytic phage and depolymerase also have potential as alternative

  9. Role of capsular polysaccharide (CPS) in biofilm formation and regulation of CPS production by quorum-sensing in Vibrio vulnificus.

    PubMed

    Lee, Kyung-Jo; Kim, Jeong-A; Hwang, Won; Park, Soon-Jung; Lee, Kyu-Ho

    2013-11-01

    Extracellular polysaccharides, such as lipopolysaccharide and loosely associated exopolysaccharides, are essential for Vibrio vulnificus to form biofilms. The role of another major component of the V. vulnificus extracellular matrix, capsular polysaccharide (CPS), which contributes to colony opacity, has been characterized in biofilm formation. A CPS-deficient mutant, whose wbpP gene encoding UDP-GlcNAc C4-epimerase was knocked out, formed significantly more biofilm than wild type, due to increased hydrophobicity of the cell surface, adherence to abiotic surfaces and cell aggregation. To elucidate the direct effect of CPS on biofilm structure, extracted CPS and a CPS-degrading enzyme, α-N-acetylgalactosaminidase, were added in biofilm assays, resulting in reduction and increment of biofilm sizes respectively. Therefore, it is suggested that CPS play a critical role in determining biofilm size by restricting continual growth of mature biofilms. Since CPS is required after maturation, CPS biosynthesis should be controlled in a cell density-dependent manner, e.g. by quorum-sensing (QS) regulation. Analysing transcription of the CPS gene cluster revealed that it was activated by SmcR, a QS master regulator, via binding to the upstream region of the cluster. Therefore, CPS was produced when biofilm cell density reached high enough to turn on QS regulation and limited biofilms to appropriate sizes.

  10. E. coli Group 1 Capsular Polysaccharide Exportation Nanomachinary as a Plausible Antivirulence Target in the Perspective of Emerging Antimicrobial Resistance

    PubMed Central

    Sachdeva, Shivangi; Palur, Raghuvamsi V.; Sudhakar, Karpagam U.; Rathinavelan, Thenmalarchelvi

    2017-01-01

    Bacteria evolving resistance against the action of multiple drugs and its ability to disseminate the multidrug resistance trait(s) across various strains of the same bacteria or different bacterial species impose serious threat to public health. Evolution of such multidrug resistance is due to the fact that, most of the antibiotics target bacterial survival mechanisms which exert selective pressure on the bacteria and aids them to escape from the action of antibiotics. Nonetheless, targeting bacterial virulence strategies such as bacterial surface associated polysaccharides biosynthesis and their surface accumulation mechanisms may be an attractive strategy, as they impose less selective pressure on the bacteria. Capsular polysaccharide (CPS) or K-antigen that is located on the bacterial surface armors bacteria from host immune response. Thus, unencapsulating bacteria would be a good strategy for drug design, besides CPS itself being a good vaccine target, by interfering with CPS biosynthesis and surface assembly pathway. Gram-negative Escherichia coli uses Wzy-polymerase dependent (Groups 1 and 4) and ATP dependent (Groups 1 and 3) pathways for CPS production. Considering E. coli as a case in point, this review explains the structure and functional roles of proteins involved in Group 1 Wzy dependent CPS biosynthesis, surface expression and anchorage in relevance to drug and vaccine developments. PMID:28217109

  11. Evidence for covalent attachment of phospholipid to the capsular polysaccharide of Haemophilus influenzae type b.

    PubMed Central

    Kuo, J S; Doelling, V W; Graveline, J F; McCoy, D W

    1985-01-01

    Cells of Haemophilus influenzae type b were grown in a liquid medium containing [3H]palmitate or [14C]ribose or both for two generations of exponential growth. Radiolabeled type-specific capsular polysaccharide, polyribosyl ribitol phosphate (PRP), was purified from the culture supernatant by Cetavlon precipitation, ethanol fractionation, and hydroxylapatite and Sepharose 4B chromatography. The doubly labeled ( [3H]palmitate and [14C]ribose) PRP preparation was found to coelute in a single peak from a Sepharose 4B column, suggesting that both precursors were incorporated into the purified PRP. A singly labeled ( [3H]palmitate) purified PRP preparation was found to be quantitatively immune precipitated by human serum containing antibody against PRP. The radioactivity of this preparation could not be dissociated from PRP by treatment with chloroform-methanol, 6 M urea, sodium dodecyl sulfate, or Zwittergent. Only after acid, alkaline, or phospholipase A2 treatment of PRP labeled with [3H]palmitate or [3H]palmitate and [14C]ribose followed by chloroform-methanol extraction could most of the 3H-radioactivity be recovered in the organic phase. The chloroform-soluble acid-hydrolyzed or phospholipase A2-treated product was identified as palmitic acid after thin-layer chromatography. These results strongly suggest that a phospholipid moiety is covalently associated with the H. influenzae type b polysaccharide PRP. Images PMID:3926752

  12. Evidence for covalent attachment of phospholipid to the capsular polysaccharide of Haemophilus influenzae type b

    SciTech Connect

    Kuo, J.S.; Doelling, V.W.; Graveline, J.F.; McCoy, D.W.

    1985-08-01

    Cells of Haemophilus influenzae type b were grown in a liquid medium containing (TH)palmitate or ( UC)ribose or both for two generations of exponential growth. Radiolabeled type-specific capsular polysaccharide, polyribosyl ribitol phosphate (PRP), was purified from the culture supernatant by Cetavlon precipitation, ethanol fractionation, and hydroxylapatite and Sepharose 4B chromatography. The doubly labeled ( (TH)palmitate and ( UC)ribose) PRP preparation was found to coelute in a single peak from a Sepharose 4B column, suggesting that both precursors were incorporated into the purified PRP. A singly labeled ( (TH)palmitate) purified PRP preparation was found to be quantitatively immune precipitated by human serum containing antibody against PRP. Only after acid, alkaline, or phospholipase A2 treatment of PRP labeled with (TH)palmitate or (TH)palmitate and ( UC)ribose followed by chloroform-methanol extraction could most of the TH-radioactivity be recovered in the organic phase. The chloroform-soluble acid-hydrolyzed or phospholipase A2-treated product was identified as palmitic acid after thin-layer chromatography. These results strongly suggest that a phospholipid moiety is covalently associated with the H. influenzae type b polysaccharide PRP.

  13. Highly Dynamic Genomic Loci Drive the Synthesis of Two Types of Capsular or Secreted Polysaccharides within the Mycoplasma mycoides Cluster

    PubMed Central

    Bertin, Clothilde; Pau-Roblot, Corinne; Courtois, Josiane; Manso-Silván, Lucía; Tardy, Florence; Poumarat, François; Citti, Christine; Sirand-Pugnet, Pascal; Gaurivaud, Patrice

    2014-01-01

    Mycoplasmas of the Mycoplasma mycoides cluster are all ruminant pathogens. Mycoplasma mycoides subsp. mycoides is responsible for contagious bovine pleuropneumonia and is known to produce capsular polysaccharide (CPS) and exopolysaccharide (EPS). Previous studies have strongly suggested a role for Mycoplasma mycoides subsp. mycoides polysaccharides in pathogenicity. Mycoplasma mycoides subsp. mycoides-secreted EPS was recently characterized as a β(1→6)-galactofuranose homopolymer (galactan) identical to the capsular product. Here, we extended the characterization of secreted polysaccharides to all other members of the M. mycoides cluster: M. capricolum subsp. capripneumoniae, M. capricolum subsp. capricolum, M. leachii, and M. mycoides subsp. capri (including the LC and Capri serovars). Extracted EPS was characterized by nuclear magnetic resonance, resulting in the identification of a homopolymer of β(1→2)-glucopyranose (glucan) in M. capricolum subsp. capripneumoniae and M. leachii. Monoclonal antibodies specific for this glucan and for the Mycoplasma mycoides subsp. mycoides-secreted galactan were used to detect the two polysaccharides. While M. mycoides subsp. capri strains of serovar LC produced only capsular galactan, no polysaccharide could be detected in strains of serovar Capri. All strains of M. capricolum subsp. capripneumoniae and M. leachii produced glucan CPS and EPS, whereas glucan production and localization varied among M. capricolum subsp. capricolum strains. Genes associated with polysaccharide synthesis and forming a biosynthetic pathway were predicted in all cluster members. These genes were organized in clusters within two loci representing genetic variability hot spots. Phylogenetic analysis showed that some of these genes, notably galE and glf, were acquired via horizontal gene transfer. These findings call for a reassessment of the specificity of the serological tests based on mycoplasma polysaccharides. PMID:25398856

  14. Preparation of pneumococcal capsular polysaccharide-protein conjugate vaccines utilizing new fragmentation and conjugation technologies.

    PubMed

    Pawlowski, A; Källenius, G; Svenson, S B

    2000-03-17

    There is a global urgent need for a new efficient and inexpensive vaccine to combat pneumococcal disease, which should also be affordable in developing countries. In view of this need a simple low-cost technique to prepare such a vaccine was developed. The preparation of serotype 14 and 23F pneumococcal capsular polysaccharide (PnPS)-protein conjugates to be included in a forthcoming multivalent PnPS conjugate vaccine is described. Commercial lots of PnPSs produced according to Good Manufacturing Practice from Streptococcus pneumoniae serotype 14 (PS14) and 23F (PS23F) were partially depolymerized by sonication or irradiation in an electron beam accelerator. The PnPS fragments were conjugated to tetanus toxoid (TT) using a recently developed conjugation chemistry. The application of these new simple, efficient and inexpensive fragmentation and conjugation technologies allowed the synthesis of several PnPS-protein conjugates containing PnPS fragments of preselected sizes and differing in the degree of substitution. The PS14TT and PS23FTT conjugate vaccine candidates were characterized chemically and their immunogenicity was evaluated in rabbits and mice. All PnPS conjugate vaccines, unlike the corresponding plain polysaccharides, produced high IgG titres in both animal species. The PS14TT conjugates tended to be more immunogenic than the PS23FTT conjugates. The immune response to the PS14TT conjugates, but not to the PS23FTT conjugates, was related to the size of the conjugated polysaccharide hapten. Both types of conjugates elicited strong booster effects upon secondary immunizations, resulting in high IgG1, IgG2a and IgG2b titres.

  15. Immune suppression induced by Vi capsular polysaccharide is overcome by Vi-DT conjugate vaccine.

    PubMed

    An, So Jung; Yoon, Yeon Kyung; Kothari, Sudeep; Kim, Deok Ryun; Kim, Jeong Ah; Kothari, Neha; Lee, Eugene; Park, Tai Hyun; Carbis, Rodney

    2012-02-01

    The influence pre-exposure of mice to Vi capsular polysaccharide, purified from Salmonella enterica Serovar Typhi, on the subsequent immune response induced by a Vi-diphtheria toxoid (Vi-DT) conjugate was evaluated. Vi induced low anti Vi IgG titers with the dominant subclass being IgG3. The Vi-DT conjugate induced high titers of anti Vi IgG with the dominant subclass being IgG1 but with considerable quantities of IgG2a, IgG2b and IgG3. Priming of mice with Vi suppressed the response to a subsequent dose of conjugate and the suppression was overcome by a second dose of conjugate. Priming with conjugate prevented suppression of the anti Vi response and subsequent dosing with Vi raised titers back to previous levels but did not boost to new higher levels. The anti DT IgG response to one dose of conjugate was relatively strong and protracted and continued to rise for 12 weeks, compared to the response to one dose of DT which was poor and peaked at two weeks. The prolonged anti DT response was most likely due to the slow release of DT from the conjugate lattice as it degrades within the mouse resulting in a continuous stimulation of the immune response. The presence of increasing amounts of un-conjugated Vi, up to 50%, administered with the conjugate resulted in increasingly higher levels of both anti Vi and anti DT. Larger amounts of un-conjugated Vi inhibited the anti Vi response. These findings have implications for vaccine quality and a limit for un-conjugated polysaccharide should not exceed 50% and from a vaccine program perspective if the results presented here translate to humans then a Vi conjugate, once it becomes available, should replace Vi polysaccharide vaccines.

  16. Binding of purified and radioiodinated capsular polysaccharides from Cryptococcus neoformans serotype A strains to capsule-free mutants

    SciTech Connect

    Small, J.M.; Mitchell, T.G.

    1986-12-01

    Strains 6, 15, 98, 110, and 145 of Cryptococcus neoformans serotype A vary in capsule size, animal virulence, and susceptibility to in vitro phagocytosis. The isolated capsular polysaccharides (CPSs) differ in monosaccharide composition ratios and molecular size, as determined by gel filtration. The purpose of this investigation was to characterize the binding of CPSs to capsule-free mutants of C. neoformans and to examine CPSs from these strains for differences in their ability to bind, to determine whether such differences might explain the variation in the pathobiology of these strains. CPSs were partially periodate oxidized, tyraminated, iodinated with /sup 125/I, and used in binding studies with two capsule-free mutants of C. neoformans, strain 602 and Cap59. Binding was specific for yeast species and for polysaccharide and was saturable, which is consistent with a receptor-mediated mechanism of attachment. Binding occurred rapidly and was only slowly reversible. Binding was also independent of pH from pH 5.5 to 8, of cation concentrations, and of competition by sugars up to 1.0 M concentrations. Only a portion of CPS was capable of binding, and strains varied in the extent to which their CPS bound. CPS-15-IV (peak IV was the major polysaccharide peak on DEAE-cellulose chromatography of CPS from strain 15) had the highest proportion of binding (40%), followed by CPS from strains 98, 6, 145, 110, and 15-III (peak III was an earlier eluting fraction of CPS from strain 15). The CPSs differed similarly in their ability to competitively inhibit binding. Treatment of CPS, but not yeast cells, with proteinase XIV abolished binding without altering the CPS gross structure. Treatment of yeast cells with proteases, heat, or formaldehyde did not alter binding, and both strain 602 and Cap59 bound CPS similarly. Binding to encapsulated yeast cells was minimal.

  17. Improvement in the purification process of the capsular polysaccharide from Haemophilus influenzae type b by using tangential ultrafiltration and diafiltration.

    PubMed

    Albani, Silvia Maria Ferreira; da Silva, Mateus Ribeiro; Takagi, Mickie; Cabrera-Crespo, Joaquin

    2012-08-01

    Capsular polysaccharide produced by Haemophilus influenzae b (Hib) is the main virulent agent and used as the antigen in the vaccine formulation. In this study, an improved process of polysaccharide purification was established based on tangential flow ultrafiltration using detergents (cocamidopropyl betaine and sodium deoxycholate), two selective ethanol precipitations steps, and extensive enzymatic hydrolysis as strategy. The relative purity (RP) related to protein and nucleic acids were 122~263 and 294~480, respectively, and compatible with the specifications established by the World Health Organization for Hib vaccine, RP≥100. These results make this process simple, cheaper, efficient, environmentally friendly, and prone to be scaled up.

  18. Polysaccharides of the Genus Bacillus Cross-Reactive with the Capsular Polysaccharides of Diplococcus pneumoniae Type III, Haemophilus influenzae Type b, and Neisseria meningitidis Group A

    PubMed Central

    Myerowitz, Richard L.; Gordon, Ruth E.; Robbins, John B.

    1973-01-01

    We studied 174 strains of the genus Bacillus for cross-reacting antigens to the capsular polysaccharides of groups A and C meningococcus, types I and III pneumococcus, and Haemophilus influenzae type b. Cross-reactions were detected by immunodiffusion in agarose gel by using type-specific antisera and confirmed by absorption and inhibition experiments. Of 20 Bacillus pumilis strains, six had an antigen cross-reacting with group A meningococcal polysaccharide. Other cross-reactions included one strain of B. pumilis with H. influenzae type b, one of B. cereus var. mycoides with pneumococcus type III, and one of B. alvei with both type b and SIII polysaccharides. These cross-reacting antigens are polysaccharides of vegetative cells and may be extracellular in location. Because these bacilli have antigens cross-reacting with the virulence factors of pyogenic bacteria, they may, as normal flora, be an antigenic stimulus for “natural” serum anti-capsular antibodies to the type b Haemophilus and group A meningococcus polysaccharides. Images PMID:4150383

  19. Polysaccharides of the genus Bacillus cross-reactive with the capsular polysaccharides of Diplococcus pneumoniae type 3, Haemophilus influenzae type b, and Neisseria meningitidis group A.

    PubMed

    Myerowitz, R L; Gordon, R E; Robbins, J B

    1973-12-01

    We studied 174 strains of the genus Bacillus for cross-reacting antigens to the capsular polysaccharides of groups A and C meningococcus, types I and III pneumococcus, and Haemophilus influenzae type b. Cross-reactions were detected by immunodiffusion in agarose gel by using type-specific antisera and confirmed by absorption and inhibition experiments. Of 20 Bacillus pumilis strains, six had an antigen cross-reacting with group A meningococcal polysaccharide. Other cross-reactions included one strain of B. pumilis with H. influenzae type b, one of B. cereus var. mycoides with pneumococcus type III, and one of B. alvei with both type b and SIII polysaccharides. These cross-reacting antigens are polysaccharides of vegetative cells and may be extracellular in location. Because these bacilli have antigens cross-reacting with the virulence factors of pyogenic bacteria, they may, as normal flora, be an antigenic stimulus for "natural" serum anti-capsular antibodies to the type b Haemophilus and group A meningococcus polysaccharides.

  20. Anti-Biofilm Activity: A Function of Klebsiella pneumoniae Capsular Polysaccharide

    PubMed Central

    Dos Santos Goncalves, Marina; Delattre, Cédric; Balestrino, Damien; Charbonnel, Nicolas; Elboutachfaiti, Redouan; Wadouachi, Anne; Badel, Stéphanie; Bernardi, Thierry; Michaud, Philippe; Forestier, Christiane

    2014-01-01

    Competition and cooperation phenomena occur within highly interactive biofilm communities and several non-biocides molecules produced by microorganisms have been described as impairing biofilm formation. In this study, we investigated the anti-biofilm capacities of an ubiquitous and biofilm producing bacterium, Klebsiella pneumoniae. Cell-free supernatant from K. pneumoniae planktonic cultures showed anti-biofilm effects on most Gram positive bacteria tested but also encompassed some Gram negative bacilli. The anti-biofilm non-bactericidal activity was further investigated on Staphylococcus epidermidis, by determining the biofilm biomass, microscopic observations and agglutination measurement through a magnetic bead-mediated agglutination test. Cell-free extracts from K. pneumoniae biofilm (supernatant and acellular matrix) also showed an influence, although to a lesser extend. Chemical analyses indicated that the active molecule was a high molecular weight polysaccharide composed of five monosaccharides: galactose, glucose, rhamnose, glucuronic acid and glucosamine and the main following sugar linkage residues [→2)-α-l-Rhap-(1→]; [→4)-α-l-Rhap-(1→]; [α-d-Galp-(1→]; [→2,3)-α-d-Galp-(1→]; [→3)-β-d-Galp-(1→] and, [→4)-β-d-GlcAp-(1→]. Characterization of this molecule indicated that this component was more likely capsular polysaccharide (CPS) and precoating of abiotic surfaces with CPS extracts from different serotypes impaired the bacteria-surface interactions. Thus the CPS of Klebsiella would exhibit a pleiotropic activity during biofilm formation, both stimulating the initial adhesion and maturation steps as previously described, but also repelling potential competitors. PMID:24932475

  1. Two capsular polysaccharides enable Bacillus cereus G9241 to cause anthrax-like disease.

    PubMed

    Oh, So-Young; Budzik, Jonathan M; Garufi, Gabriella; Schneewind, Olaf

    2011-04-01

    Bacillus cereus G9241 causes an anthrax-like respiratory illness in humans; however, the molecular mechanisms of disease pathogenesis are not known. Genome sequencing identified two putative virulence plasmids proposed to provide for anthrax toxin (pBCXO1) and/or capsule expression (pBC218). We report here that B. cereus G9241 causes anthrax-like disease in immune-competent mice, which is dependent on each of the two virulence plasmids. pBCXO1 encodes pagA1, the homologue of anthrax protective antigen, as well as hasACB, providing for hyaluronic acid capsule formation, two traits that each contribute to disease pathogenesis. pBC218 harbours bpsX-H, B. cereus exo-polysaccharide, which produce a second capsule. During infection, B. cereus G9241 elaborates both hasACB and bpsX-H capsules, which together are essential for the establishment of anthrax-like disease and the resistance of bacilli to phagocytosis. A single nucleotide deletion causes premature termination of hasA translation in Bacillus anthracis, which is known to escape phagocytic killing by its pXO2 encoded poly-d-γ-glutamic acid (PDGA) capsule. Thus, multiple different gene clusters endow pathogenic bacilli with capsular material, provide for escape from innate host immune responses and aid in establishing the pathogenesis of anthrax-like disease.

  2. Agglutination by anti-capsular polysaccharide antibody is associated with protection against experimental human pneumococcal carriage

    PubMed Central

    Reiné, J; Zangari, T; Owugha, JT; Pennington, SH; Gritzfeld, JF; Wright, AD; Collins, AM; van Selm, S; de Jonge, MI; Gordon, SB; Weiser, JN; Ferreira, DM

    2016-01-01

    The ability of pneumococcal conjugate vaccine (PCV) to decrease transmission by blocking the acquisition of colonization has been attributed to herd immunity. We describe the role of mucosal IgG to capsular polysaccharide (CPS) in mediating protection from carriage, translating our findings from a murine model to humans. We used a flow-cytometric assay to quantify antibody-mediated agglutination demonstrating that hyperimmune sera generated against an unencapsulated mutant was poorly agglutinating. Passive immunization with this antiserum was ineffective to block acquisition of colonization compared to agglutinating antisera raised against the encapsulated parent strain. In the human challenge model samples were collected from PCV and control vaccinated adults. In PCV-vaccinated subjects IgG levels to CPS were increased in serum and nasal wash (NW). IgG to the inoculated strain CPS dropped in NW samples after inoculation suggesting its sequestration by colonizing pneumococci. In post-vaccination NW samples pneumococci were heavily agglutinated compared to pre-vaccination samples in subjects protected against carriage. Our results indicate that pneumococcal agglutination mediated by CPS specific antibodies is a key mechanism of protection against acquisition of carriage. Capsule may be the only vaccine target that can elicit strong agglutinating antibody responses, leading to protection against carriage acquisition and generation of herd immunity. PMID:27579859

  3. Two capsular polysaccharides enable Bacillus cereus G9241 to cause anthrax-like disease

    PubMed Central

    Oh, So-Young; Budzik, Jonathan M.; Garufi, Gabriella; Schneewind, Olaf

    2012-01-01

    Summary Bacillus cereus G9241 causes an anthrax-like respiratory illness in humans, however the molecular mechanisms of disease pathogenesis are not known. Genome sequencing identified two putative virulence plasmids proposed to provide for anthrax toxin (pBCXO1) and/or capsule expression (pBC218). We report here that B. cereus G9241 causes anthrax-like disease in immune-competent mice, which is dependent on each of the two virulence plasmids. pBCXO1 encodes pagA1, the homolog of anthrax protective antigen, as well as hasACB, providing for hyaluronic acid capsule formation, two traits that each contribute to disease pathogenesis. pBC218 harbors bpsX-H, Bacillus cereus exo-polysaccharide, which produce a second capsule. During infection, B. cereus G9241 elaborates both hasACB and bpsX-H capsules, which together are essential for the establishment of anthrax-like disease and the resistance of bacilli to phagocytosis. A single nucleotide deletion causes premature termination of hasA translation in B. anthracis, which is known to escape phagocytic killing by its pXO2 encoded poly-D-γ-glutamic acid (PDGA) capsule. Thus, multiple different gene clusters endow pathogenic bacilli with capsular material, provide for escape from innate host immune responses and aid in establishing the pathogenesis of anthrax-like disease. PMID:21371137

  4. Synthesis of a Glucuronic Acid‐Containing Thioglycoside Trisaccharide Building Block and Its Use in the Assembly of Cryptococcus Neoformans Capsular Polysaccharide Fragments†

    PubMed Central

    Guazzelli, Lorenzo; Ulc, Rebecca

    2015-01-01

    Abstract As part of an ongoing project aimed at identifying protective capsular polysaccharide epitopes for the development of vaccine candidates against the fungal pathogen Cryptococcus neoformans, the synthesis and glycosylation properties of a naphthalenylmethyl (NAP) orthogonally protected trisaccharide thioglycoside, a common building block for construction of serotype B and C capsular polysaccharide structures, were investigated. Ethyl (benzyl 2,3,4‐tri‐O‐benzyl‐β‐d‐glucopyranosyl‐ uronate)‐(1→2)‐[2,3,4‐tri‐O‐benzyl‐β‐d‐xylopyranosyl‐(1→4)]‐6‐O‐benzyl‐3‐O‐(2‐naphthalenylmethyl)‐1‐thio‐α‐d‐mannopyranoside was prepared and used both as a donor and an acceptor in glycosylation reactions to obtain spacer equipped hexa‐ and heptasaccharide structures suitable either for continued elongation or for deprotection and printing onto a glycan array or conjugation to a carrier protein. The glycosylation reactions proceeded with high yields and α‐selectivity, proving the viability of the building block approach also for construction of 4‐O‐xylosyl‐containing C. neoformans CPS structures. PMID:27308199

  5. Nonopsonic binding of Mycobacterium tuberculosis to complement receptor type 3 is mediated by capsular polysaccharides and is strain dependent.

    PubMed Central

    Cywes, C; Hoppe, H C; Daffé, M; Ehlers, M R

    1997-01-01

    The choice of host cell receptor and the mechanism of binding (opsonic versus nonopsonic) may influence the intracellular fate of Mycobacterium tuberculosis. We have identified two substrains of M. tuberculosis H37Rv, designated H37Rv-CC and -HH, that differed in their modes of binding to complement receptor type 3 (CR3) expressed in transfected Chinese hamster ovary (CHO-Mac-1) cells: H37Rv-CC bound nonopsonically, whereas H37Rv-HH bound only after opsonization in fresh serum. H37Rv-CC also bound nonopsonically to untransfected CHO cells, whereas H37Rv-HH binding was enhanced by serum and was mediated by the 1D1 antigen, a bacterial adhesin previously identified as a polar phosphatidylinositol mannoside. H37Rv-CC and -HH had identical IS6110 DNA fingerprint patterns. Of five M. tuberculosis clinical isolates examined, four displayed the same binding phenotype as H37Rv-CC, as did the Erdman strain, whereas one isolate, as well as Mycobacterium smegmatis, behaved like H37Rv-HH. Nonopsonic binding of H37Rv-CC to CHO cell-expressed CR3 was apparently to the beta-glucan lectin site, as it was cation independent and inhibited by laminarin (seaweed beta-glucan) and N-acetylglucosamine; laminarin also inhibited the binding of H37Rv-CC to monocyte-derived macrophages. Further, binding of H37Rv-CC to CHO-Mac-1 cells was inhibited by prior agitation of bacteria with glass beads (which strips outer capsular polysaccharides) and by preincubation with amyloglucosidase, as well as by the presence of capsular D-glucan and D-mannan from M. tuberculosis Erdman, but not by Erdman D-arabino-D-mannan, yeast mannan, or capsular components from H37Rv-HH. Analysis of capsular carbohydrates revealed that H37Rv-CC expressed 5-fold more glucose and 2.5-fold more arabinose and mannose than H37Rv-HH. Flow cytometric detection of surface epitopes indicated that H37Rv-CC displayed twofold less surface-exposed phosphatidylinositol mannoside and bound complement C3 less efficiently than H37Rv

  6. A cryptococcal capsular polysaccharide mimotope prolongs the survival of mice with Cryptococcus neoformans infection.

    PubMed

    Fleuridor, R; Lees, A; Pirofski, L

    2001-01-15

    Defined Abs to the Cryptococcus neoformans capsular polysaccharide glucuronoxylomannan (GXM) have been shown to be protective against experimental cryptococcosis. This suggests that if a vaccine could induce similar Abs it might protect against infection. However, the potential use of a GXM-based vaccine has been limited by evidence that GXM is a poor immunogen that can induce nonprotective and deleterious, as well as protective, Abs, and that the nature of GXM oligosaccharide epitopes that can elicit a protective response is unknown. In this study, we investigated whether a peptide surrogate for a GXM epitope could induce an Ab response to GXM in mice. The immunogenicity of peptide-protein conjugates produced by linking a peptide mimetic of GXM, P13, to either BSA, P13-BSA, or tetanus toxoid, P13-tetanus toxoid, was examined in BALB/c and CBA/n mice that received four s.c. injections of the conjugates at 14- to 30-day intervals. All mice immunized with conjugate produced IgM and IgG to P13 and GXM. Challenge of conjugate-immunized mice with C. neoformans revealed longer survival and lower serum GXM levels than control mice. These results indicate that 1) P13 is a GXM mimotope and 2) that it induced a protective response against C. neoformans in mice. P13 is the first reported mimotope of a C. neoformans Ag. Therefore, the P13 conjugates are vaccine candidates for C. neoformans and their efficacy in this study suggests that peptide mimotopes selected by protective Abs deserve further consideration as vaccine candidates for encapsulated pathogens.

  7. Therapeutic efficacy of a conjugate vaccine containing a peptide mimotope of cryptococcal capsular polysaccharide glucuronoxylomannan.

    PubMed

    Datta, Kausik; Lees, Andrew; Pirofski, Liise-anne

    2008-08-01

    Vaccination with P13, a peptide mimotope of the cryptococcal capsular polysaccharide glucuronoxylomannan (GXM), has been shown to confer protection against a subsequent lethal Cryptococcus neoformans challenge. In this study, we sought to investigate whether P13-based vaccines could be effective in an already-established infection. To address this question, we developed a systemic chronic cryptococcal infection model. We vaccinated chronically infected mice with P13-protein conjugates and monitored their survival. Compared to the controls, the conjugates prolonged the survival of chronically infected mice. The degree of protection was a function of the mouse strain (BALB/c or C57BL/6), the carrier protein (tetanus toxoid or diphtheria toxoid), and the route of infection (intraperitoneal or intravenous). Serum GXM levels were correlated with the day of death, but the correlation was driven by the carrier protein and mouse strain. The passive transfer of heat-treated sera from P13 conjugate-vaccinated mice conferred protection to naïve BALB/c mice, indicating that antibody immunity could contribute to protection. The measurement of peripheral blood cytokine (gamma interferon [IFN-gamma], interleukin-10 [IL-10], and IL-6) gene expression showed that P13 conjugate-vaccinated BALB/c and C57BL/6 mice mounted a strong Th2 (IL-10)-like response relative to the Th1 (IFN-gamma)-like response, with the degree depending on the mouse strain and carrier protein. Taken together, our data suggest that a vaccine could hold promise in the setting of chronic cryptococcosis, and that vaccine efficacy could depend on immunomodulation and augmentation of the natural immune response of the host.

  8. The efficacy of pneumococcal capsular polysaccharide-specific antibodies to serotype 3 Streptococcus pneumoniae requires macrophages.

    PubMed

    Fabrizio, Kevin; Manix, Catherine; Tian, Haijun; van Rooijen, Nico; Pirofski, Liise-anne

    2010-11-03

    The efficacy of antibody immunity against Streptococcus pneumoniae stems from the ability of opsonic, serotype (ST)-specific antibodies to pneumococcal capsular polysaccharide (PPS) to facilitate killing of the homologous ST by host phagocytes. However, PPS-specific antibodies have been identified that are protective in mice, but do not promote opsonic killing in vitro, raising the question of how they mediate protection in vivo. To probe this question, we investigated the dependence of antibody efficacy against lethal systemic (intraperitoneal, i.p.) infection with Streptococcus pneumoniae serotype 3 (ST3) on macrophages and neutrophils for the following PPS3-specific monoclonal antibodies (MAbs) in survival experiments in mice using a non-opsonic human IgM (A7), a non-opsonic mouse IgG1 (1E2) and an opsonic mouse IgG1 (5F6). The survival of A7- and PPS3-specific and isotype control MAb-treated neutrophil-depleted and neutrophil-sufficient and macrophage-depleted and macrophage-sufficient mice were determined after i.p. challenge with ST3 strains 6303 and WU2. Neutrophils were dispensable for A7 and the mouse MAbs to mediate protection in this model, but macrophages were required for the efficacy of A7 and optimal mouse MAb-mediated protection. For A7-treated mice, macrophage-depleted mice had higher blood CFU, cytokines and peripheral neutrophil levels than macrophage-sufficient mice, and macrophage-sufficient mice had lower tissue bacterial burdens than control MAb-treated mice. These findings demonstrate that macrophages contribute to opsonic and non-opsonic PPS3-specific MAb-mediated protection against ST3 infection by enhancing bacterial clearance and suggest that neutrophils do not compensate for the absence of macrophages in the model used in this study.

  9. Cell growth rate regulates expression of group B Streptococcus type III capsular polysaccharide.

    PubMed Central

    Paoletti, L C; Ross, R A; Johnson, K D

    1996-01-01

    The capsular polysaccharide (CPS) of group B streptococci (GBS) is an important virulence factor that also serves to protect cells from nonspecific host defense mechanisms. Expression of CPS by GBS, as with other encapsulated bacterial pathogens, is not constitutive but varies during growth in vitro and in primary cultures isolated from different sites of infection. Despite this understanding, little is known about regulation of this surface-expressed carbohydrate antigen in GBS. Here we report that expression of type III CPS by GBS strain M781 grown in continuous culture with a modified chemically defined medium is regulated by growth rate. Cells in steady state at mass doubling times (tds) of 0.8, 1.4, and 1.6 h expressed an average of sixfold more cell-associated CPS than did cells held at tds of 2.3 and 11 h. Strain M781 grown at a td of 1.4 h repeatedly produced more type III CPS than those held at a td of 11.0 h, even when limited for glucose, pyridoxamine, or thiamine. In our studies, > or = 93% of the total CPS expressed by strain M781 was cell associated. Strain M781 grown at a td of 11.0 h (i.e., lowered CPS expression) was susceptible to in vitro complement-mediated opsonophagocytosis and killing by human peripheral blood leukocytes, whereas cells grown at a td of 1.4 h (i.e., higher CPS expression) were not killed unless type III CPS-specific antibody was present. Factors that allow GBS to asymptomatically colonize women yet cause invasive infection to both mother and infant are poorly understood. Our results shed new light on parameters that regulate the pathogenic potential of GBS and may also serve as a way to discern more fully the genetics and biochemistry of GBS capsule synthesis. PMID:8606082

  10. Study of various presentation forms for a peptide mimetic of Neisseria meningitidis serogroup B capsular polysaccharide.

    PubMed

    Garay, Hilda; Menéndez, Tamara; Cruz-Leal, Yoelys; Coizeau, Edelgis; Noda, Jesus; Morera, Vivian; Guillén, Gerardo; Albericio, Fernando; Reyes, Osvaldo

    2011-01-19

    The formulation of a broadly protective vaccine to prevent the serogroup B Neisseria meningitidis (MenB) disease is still an unmet medical need. We have previously reported the induction of bactericidal and protective antibodies against MenB after immunization of mice with a phage-displayed peptide named 4 L-5. This peptide mimics a capsular polysaccharide (CPS) epitope in MenB. With the aim of developing vaccine formulations that could be used in humans, we evaluate in this study various forms of presentation to the immune system of the 4 L-5 sequence, based on synthetic peptides. We synthesized the following: (i) a linear 4 L-5 peptide, (ii) a multiple antigen peptide containing four copies of the 4 L-5 sequence (named MAP), which was then dimerized, and the product named dimeric MAP, and (iii) a second multiple antigen peptide, in this case with two copies of the 4 L-5 sequence and a copy of a T-helper cell epitope of tetanus toxoid, which was then dimerized and the product named MAP-TT. The linear peptide, the MAP, and the dimeric MAP were conjugated to the carrier protein P64K by different conjugation methods. Plain antigens and antigens coupled to P64K were used to immunize BALB/c mice. Of those variants that gave immunogenic results, MAP-TT rendered the highest levels of specific antipeptide IgG antibodies and serum bactericidal activity. These results can find application in the development of meningococcal vaccine candidates and in peptide-based vaccines strategies.

  11. Protection against Streptococcus suis Serotype 2 Infection Using a Capsular Polysaccharide Glycoconjugate Vaccine

    PubMed Central

    Calzas, Cynthia; Shiao, Tze Chieh; Neubauer, Axel; Kempker, Jennifer; Roy, René; Gottschalk, Marcelo

    2016-01-01

    Streptococcus suis serotype 2 is an encapsulated bacterium and one of the most important bacterial pathogens in the porcine industry. Despite decades of research for an efficient vaccine, none is currently available. Based on the success achieved with other encapsulated pathogens, a glycoconjugate vaccine strategy was selected to elicit opsonizing anti-capsular polysaccharide (anti-CPS) IgG antibodies. In this work, glycoconjugate prototypes were prepared by coupling S. suis type 2 CPS to tetanus toxoid, and the immunological features of the postconjugation preparations were evaluated in vivo. In mice, experiments evaluating three different adjuvants showed that CpG oligodeoxyribonucleotide (ODN) induces very low levels of anti-CPS IgM antibodies, while the emulsifying adjuvants Stimune and TiterMax Gold both induced high levels of IgGs and IgM. Dose-response trials comparing free CPS with the conjugate vaccine showed that free CPS is nonimmunogenic independently of the dose used, while 25 μg of the conjugate preparation was optimal in inducing high levels of anti-CPS IgGs postboost. With an opsonophagocytosis assay using murine whole blood, sera from immunized mice showed functional activity. Finally, the conjugate vaccine showed immunogenicity and induced protection in a swine challenge model. When conjugated and administered with emulsifying adjuvants, S. suis type 2 CPS is able to induce potent IgM and isotype-switched IgGs in mice and pigs, yielding functional activity in vitro and protection against a lethal challenge in vivo, all features of a T cell-dependent response. This study represents a proof of concept for the potential of glycoconjugate vaccines in veterinary medicine applications against invasive bacterial infections. PMID:27113360

  12. Hydrolytic stability of pneumococcal group 6 (type 6A and 6B) capsular polysaccharides.

    PubMed

    Zon, G; Szu, S C; Egan, W; Robbins, J D; Robbins, J B

    1982-07-01

    The hydrolyses of the immunologically cross-reactive and constitutionally isomeric group 6 pneumococcal polysaccharides, types 6A and 6B, were investigated by 31P nuclear magnetic resonance spectroscopy, gel filtration through Sepharose 4B, reducing-sugar analysis, and rocket immunoelectrophoresis. Phosphorus nuclear magnetic resonance spectroscopy showed that cleavage of the repeating-unit phosphodiester linkages at pH 10, 60 degrees C was considerably faster (greater than 10(3) ) for the type 6A than the type 6B polysaccharide. Under these reaction conditions, 31P nuclear magnetic resonance kinetic measurements showed that the Na+ form of the type 6A polysaccharide underwent phosphodiester-linkage hydrolysis two times slower than the corresponding Ca+2 form; a stoichiometrically excess amount of Ca+2 caused a 30-fold enhancement of the latter hydrolysis rate. The spectroscopic characterization of phosphorus-containing end groups resulting from hydrolysis of the type 6A polymer provided additional mechanistic information. Heating the type 6A and 6B polysaccharides at 56 degrees C for various times led to gel filtration coefficients of distribution (Kd values) which indicated that the type 6A material underwent size reductions considerably faster than did the type 6B antigen; these increased Kd values qualitatively correlated with the loss of immunochemical reactivity measured by rocket immunoelectrophoresis. The application of a statistical theory to the depolymerization of the type 6A and 6B polysaccharides was consistent with random bond cleavage, as evidenced by the calculated versus measured gel filtration patterns. Although the molecular changes causing the size reductions were not fully elaborated, it was established that the acetal linkages of the type 6A and 6B polysaccharides were comparatively resistant to hydrolysis and that depolymerization by hydrolysis of the phosphodiester linkage was a major factor only in the type 6A structure. It was concluded

  13. Hydrolytic stability of pneumococcal group 6 (type 6A and 6B) capsular polysaccharides.

    PubMed Central

    Zon, G; Szu, S C; Egan, W; Robbins, J D; Robbins, J B

    1982-01-01

    The hydrolyses of the immunologically cross-reactive and constitutionally isomeric group 6 pneumococcal polysaccharides, types 6A and 6B, were investigated by 31P nuclear magnetic resonance spectroscopy, gel filtration through Sepharose 4B, reducing-sugar analysis, and rocket immunoelectrophoresis. Phosphorus nuclear magnetic resonance spectroscopy showed that cleavage of the repeating-unit phosphodiester linkages at pH 10, 60 degrees C was considerably faster (greater than 10(3) ) for the type 6A than the type 6B polysaccharide. Under these reaction conditions, 31P nuclear magnetic resonance kinetic measurements showed that the Na+ form of the type 6A polysaccharide underwent phosphodiester-linkage hydrolysis two times slower than the corresponding Ca+2 form; a stoichiometrically excess amount of Ca+2 caused a 30-fold enhancement of the latter hydrolysis rate. The spectroscopic characterization of phosphorus-containing end groups resulting from hydrolysis of the type 6A polymer provided additional mechanistic information. Heating the type 6A and 6B polysaccharides at 56 degrees C for various times led to gel filtration coefficients of distribution (Kd values) which indicated that the type 6A material underwent size reductions considerably faster than did the type 6B antigen; these increased Kd values qualitatively correlated with the loss of immunochemical reactivity measured by rocket immunoelectrophoresis. The application of a statistical theory to the depolymerization of the type 6A and 6B polysaccharides was consistent with random bond cleavage, as evidenced by the calculated versus measured gel filtration patterns. Although the molecular changes causing the size reductions were not fully elaborated, it was established that the acetal linkages of the type 6A and 6B polysaccharides were comparatively resistant to hydrolysis and that depolymerization by hydrolysis of the phosphodiester linkage was a major factor only in the type 6A structure. It was concluded

  14. Type 5 and 8 capsular polysaccharides are expressed by Staphylococcus aureus isolates from rabbits, poultry, pigs, and horses.

    PubMed Central

    Poutrel, B; Sutra, L

    1993-01-01

    A total of 103 Staphylococcus aureus isolates from rabbits (n = 37), poultry (n = 33), pigs (n = 27), and horses (n = 6) and 14 Staphylococcus intermedius isolates from wild animals were serotyped for capsular polysaccharide types 5 and 8 by an enzyme-linked immunosorbent assay using polyclonal rabbit antibodies. About 98% of the S. aureus isolates were typeable. Type 5 was predominant in the poultry (75.8%) and pig (66.7%) isolates, whereas type 8 was more frequent among the isolates from rabbits (59.5%) and horses (83.3%). By contrast, none of the 14 S. intermedius isolates was typeable. PMID:8432841

  15. Identification and characterization of a DNA region involved in the export of capsular polysaccharide by Actinobacillus pleuropneumoniae serotype 5a.

    PubMed Central

    Ward, C K; Inzana, T J

    1997-01-01

    Actinobacillus pleuropneumoniae synthesizes a serotype-specific capsular polysaccharide that acts as a protective barrier to phagocytosis and complement-mediated killing. To begin understanding the role of A. pleuropneumoniae capsule in virulence, we sought to identify the genes involved in capsular polysaccharide export and biosynthesis. A 5.3-kb XbaI fragment of A. pleuropneumoniae serotype 5a J45 genomic DNA that hybridized with DNA probes specific for the Haemophilus influenzae type b cap export region was cloned and sequenced. This A. pleuropneumoniae DNA fragment encoded four open reading frames, designated cpxDCBA. The nucleotide and predicted amino acid sequences of cpxDCBA contained a high degree of homology to the capsule export genes of H. influenzae type b bexDCBA, Neisseria meningitidis group B ctrABCD, and, to a lesser extent, Escherichia coli K1 and K5 kpsE and kpsMT. When present in trans, the cpxDCBA gene cluster complemented kpsM::TnphoA or kpsT::TnphoA mutations, determined by enzyme immunoassay and by restored sensitivity to a K5-specific bacteriophage. A cpxCB probe hybridized to genomic DNA from all A. pleuropneumoniae serotypes tested, indicating that this DNA was conserved among serotypes. These data suggest that A. pleuropneumoniae produces a group II family capsule similar to those of related mucosal pathogens. PMID:9169799

  16. The contribution of naturally occurring IgM antibodies, IgM cross-reactivity and complement dependency in murine humoral responses to pneumococcal capsular polysaccharides.

    PubMed

    Jones, Hannah E; Taylor, Philip R; McGreal, Eamon; Zamze, Susanne; Wong, Simon Y C

    2009-09-25

    Immunogenicity of 12 capsular polysaccharides (CPS) from Streptococcus pneumoniae did not correlate with pre-existing levels of natural IgM anti-CPS antibodies in mice. Immunization of mice with individual CPS, with the exception of type 14 (the only neutral CPS tested), increased serum IgM that also bound other CPS serotypes independent of structural similarity or commonly known contaminants. Surprisingly only IgM response to type 4 (which has a small immunodominant epitope) was dependent on either complement C3 or complement receptors CD35/CD21. IgG anti-CPS responses were infrequently induced, but critically dependent on complement. Our results have clarified the role of complement in the induction of IgM and IgG anti-CPS antibody responses in mice and have implications for CPS vaccine development.

  17. Genotyping and investigating capsular polysaccharide synthesis gene loci of non-serotypeable Streptococcus suis isolated from diseased pigs in Canada.

    PubMed

    Zheng, Han; Qiu, Xiaotong; Roy, David; Segura, Mariela; Du, Pengchen; Xu, Jianguo; Gottschalk, Marcelo

    2017-02-20

    Streptococcus suis (S. suis) is an important swine pathogen and an emerging zoonotic agent. Most clinical S. suis strains express capsular polysaccharides (CPS), which can be typed by antisera using the coagglutination test. In this study, 79 S. suis strains recovered from diseased pigs in Canada and which could not be typed using antisera were further characterized by capsular gene typing and sequencing. Four patterns of cps locus were observed: (1) fifteen strains were grouped into previously reported serotypes but presented several mutations in their cps loci, when compared to available data from reference strains; (2) seven strains presented a complete deletion of the cps locus, which would result in an inability to synthesize capsule; (3) forty-seven strains were classified in recently described novel cps loci (NCLs); and (4) ten strains carried novel NCLs not previously described. Different virulence gene profiles (based on the presence of mrp, epf, and/or sly) were observed in these non-serotypeable strains. This study provides further insight in understanding the genetic characteristics of cps loci in non-serotypeable S. suis strains recovered from diseased animals. When using a combination of the previously described 35 serotypes and the complete NCL system, the number of untypeable strains recovered from diseased animals in Canada would be significantly reduced.

  18. Recombinant Escherichia coli K5 strain with the deletion of waaR gene decreases the molecular weight of the heparosan capsular polysaccharide.

    PubMed

    Huang, Haichan; Liu, Xiaobo; Lv, Shencong; Zhong, Weihong; Zhang, Fuming; Linhardt, Robert J

    2016-09-01

    Heparosan, the capsular polysaccharide of Escherichia coli K5 having a carbohydrate backbone similar to that of heparin, has become a potential precursor for bioengineering heparin. In the heparosan biosynthesis pathway, the gene waaR encoding α-1-, 2- glycosyltransferase catalyze s the third glucosyl residues linking to the oligosaccharide chain. In the present study, a waaR deletion mutant of E. coli K5 was constructed. The mutant showed improvement of capsule polysaccharide yield. It is interesting that the heparosan molecular weight of the mutant is reduced and may become more suitable as a precursor for the production of low molecular weight heparin derived from the wild-type K5 capsular polysaccharide.

  19. Immunogenicity and efficacy of Cryptococcus neoformans capsular polysaccharide glucuronoxylomannan peptide mimotope-protein conjugates in human immunoglobulin transgenic mice.

    PubMed

    Maitta, Robert W; Datta, Kausik; Lees, Andrew; Belouski, Shelley Sims; Pirofski, Liise-anne

    2004-01-01

    Peptide mimotopes of capsular polysaccharides have been proposed as antigens for vaccines against encapsulated pathogens. In this study, we determined the antibody response to and efficacy of P13, a peptide mimetic of the Cryptococcus neoformans capsular polysaccharide glucuronoxylomannan (GXM), in mice that produce human antibodies. P13 was conjugated to tetanus toxoid (TT) or diphtheria toxoid (DT) and administered subcutaneously in Alhydrogel with or without CpG to mice transgenic for human immunoglobulin loci (XenoMouse mice) and expressing either immunoglobulin G2 (IgG2) (G2 mice) or IgG4 (G4 mice). Mice were vaccinated and revaccinated two or three times. The serum antibody responses of the mice to GXM and P13 and antibody idiotype expression were analyzed by an enzyme-linked immunosorbent assay. The results showed that both P13-TT and P13-DT were antigenic, inducing a mimetic response to P13 in both G2 and G4 mice, and immunogenic, inducing a mimotope response including VH3 (idiotype)-positive antibodies to GXM in G2 but not G4 mice. CpG led to higher titers of IgG to P13 and GXM in P13-TT-vaccinated G2 mice. C. neoformans challenge of P13-protein conjugate-vaccinated and control G2 mice induced anamnestic IgG- and VH3-positive responses to GXM and was associated with a significantly decreased risk of death and a prolongation of survival in P13-DT-vaccinated mice compared to phosphate-buffered saline-treated or protein carrier-vaccinated mice. These findings reveal that P13 elicited a human antibody response with VH3 expression in human immunoglobulin transgenic mice that has been observed for human antibodies to GXM and support the concept that peptide mimotope-based vaccines may hold promise for the treatment of C. neoformans infections.

  20. Antibodies to Staphylococcus aureus capsular polysaccharides 5 and 8 perform similarly in vitro but are functionally distinct in vivo.

    PubMed

    Liu, Bo; Park, Saeyoung; Thompson, Christopher D; Li, Xue; Lee, Jean C

    2016-12-09

    The capsular polysaccharide (CP) produced by Staphylococcus aureus is a virulence factor that allows the organism to evade uptake and killing by host neutrophils. Polyclonal antibodies to the serotype 5 (CP5) and type 8 (CP8) capsular polysaccharides are opsonic and protect mice against experimental bacteremia provoked by encapsulated staphylococci. Thus, passive immunotherapy using CP antibodies has been considered for the prevention or treatment of invasive antibiotic-resistant S. aureus infections. In this report, we generated monoclonal antibodies (mAbs) against S. aureus CP5 or CP8. Backbone specific mAbs reacted with native and O-deacetylated CPs, whereas O-acetyl specific mAbs reacted only with native CPs. Reference strains of S. aureus and a selection of clinical isolates reacted by colony immunoblot with the CP5 and CP8 mAbs in a serotype-specific manner. The mAbs mediated in vitro CP type-specific opsonophagocytic killing of S. aureus strains, and mice passively immunized with CP5 mAbs were protected against S. aureus bacteremia. Neither CP8-specific mAbs or polyclonal antibodies protected mice against bacteremia provoked by serotype 8 S. aureus clinical isolates, although these same antibodies did protect against a serotype 5 S. aureus strain genetically engineered to produce CP8. We detected soluble CP8 in culture supernatants of serotype 8 clinical isolates and in the plasma of infected animals. Serotype 5 S. aureus released significantly less soluble CP5 in vitro and in vivo. The release of soluble CP8 by S. aureus may contribute to the inability of CP8 vaccines or antibodies to protect against serotype 8 staphylococcal infections.

  1. Regulated expression of polysaccharide utilization and capsular biosynthesis loci in biofilm and planktonic Bacteroides thetaiotaomicron during growth in chemostats

    PubMed Central

    TerAvest, Michaela A.; He, Zhen; Rosenbaum, Miriam A.; Martens, Eric C.; Cotta, Michael A.; Gordon, Jeffrey I.; Angenent, Largus T.

    2014-01-01

    Bacteroides thetaiotaomicron is a prominent member of the human distal gut microbiota that specializes in breaking down diet and host-derived polysaccharides. While polysaccharide utilization has been well studied in B. thetaiotaomicron, other aspects of its behavior are less well characterized, including the factors that allow it to maintain itself in the gut. Biofilm formation may be a mechanism for bacterial retention in the gut. Therefore, we used custom GeneChips to compare the transcriptomes of biofilm and planktonic B. thetaiotaomicron during growth in mono-colonized chemostats. We identified 1154 genes with a fold-change greater than 2, with confidence greater than or equal to 95%. Among the prominent changes observed in biofilm populations were: (i) greater expression of genes in polysaccharide utilization loci that are involved in foraging of O-glycans normally found in the gut mucosa; and (ii) regulated expression of capsular polysaccharide biosynthesis loci. Hierarchical clustering of the data with different datasets, which were obtained during growth under a range of conditions in minimal media and in intestinal tracts of gnotobiotic mice, revealed that within this group of differentially expressed genes, biofilm communities were more similar to the in vivo samples than to planktonic cells and exhibited features of substrate limitation. The current study also validates the use of chemostats as an in vitro ‘gnotobiotic’ model to study gene expression of attached populations of this bacterium. This is important to gut microbiota research, because bacterial attachment and the consequences of disruptions in attachment are difficult to study in vivo. PMID:23996813

  2. Receptor-mediated clearance of Cryptococcus neoformans capsular polysaccharide in vivo.

    PubMed

    Yauch, Lauren E; Mansour, Michael K; Levitz, Stuart M

    2005-12-01

    Cryptococcus neoformans capsular glucuronoxylomannan (GXM) is shed during cryptococcosis and taken up by macrophages. The roles of the putative GXM receptors CD14, CD18, Toll-like receptor 2 (TLR2), and TLR4 in GXM clearance from serum and deposition in the liver and spleen in receptor-deficient mice were studied. While alterations in the kinetics of GXM redistribution were seen in the mutant mice, none of the receptors was absolutely required for serum clearance or hepatosplenic accumulation.

  3. Variable Region Identical IgA and IgE to Cryptococcus neoformans Capsular Polysaccharide Manifest Specificity Differences*

    PubMed Central

    Janda, Alena; Eryilmaz, Ertan; Nakouzi, Antonio; Pohl, Mary Ann; Bowen, Anthony; Casadevall, Arturo

    2015-01-01

    In recent years several groups have shown that isotype switching from IgM to IgG to IgA can affect the affinity and specificity of antibodies sharing identical variable (V) regions. However, whether the same applies to IgE is unknown. In this study we compared the fine specificity of V region-identical IgE and IgA to Cryptococcus neoformans capsular polysaccharide and found that these differed in specificity from each other. The IgE and IgA paratopes were probed by nuclear magnetic resonance spectroscopy with 15N-labeled peptide mimetics of cryptococcal polysaccharide antigen (Ag). IgE was found to cleave the peptide at a much faster rate than V region-identical IgG subclasses and IgA, consistent with an altered paratope. Both IgE and IgA were opsonic for C. neoformans and protected against infection in mice. In summary, V-region expression in the context of the ϵ constant (C) region results in specificity changes that are greater than observed for comparable IgG subclasses. These results raise the possibility that expression of certain V regions in the context of α and ϵ C regions affects their function and contributes to the special properties of those isotypes. PMID:25778397

  4. Evaluation of the saccharide content and stability of the first WHO International Standard for Haemophilus influenzae b capsular polysaccharide.

    PubMed

    Mawas, Fatme; Bolgiano, Barbara; Rigsby, Peter; Crane, Dennis; Belgrave, Danielle; Corbel, Michael J

    2007-10-01

    Haemophilus influenzae b conjugate vaccines (Hib) are almost entirely evaluated by physico-chemical methods to ensure the consistency of manufacture of batches. As different assays are employed for the quantification of Hib capsular polysaccharide PRP (polyribosyl ribitol phosphate; 5-D-ribitol-(1-->1)-beta-D-ribose-3-phosphate) in final formulations and bulk components, there was deemed a need for an International Standard of Hib PRP polysaccharide to be made available. Ten laboratories from 8 different countries participated in a collaborative study to determine the PRP content and assess the suitability of a candidate International Standard PRP preparation (02/208). The results illustrate that a reduction in between-laboratory variability could be achieved by use of a common reference preparation and data analysis showed no significant differences in the values obtained by the different assays: ribose, phosphorus, and high performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD), suggesting the suitability of the proposed reference for use across these assays for quantification of PRP content in Hib vaccines. On the basis of the results of this study, the First International Standard for PRP, NIBSC Code 02/208, has been established by the Expert Committee of Biological Standards of the World Health Organisation, with a content of 4.933+/-0.267mg/ampoule, as determined by the ribose assays carried out by 7 of the participating laboratories.

  5. Killing of cryptococcus neoformans by Staphylococcus aureus: the role of cryptococcal capsular polysaccharide in the fungal-bacteria interaction.

    PubMed

    Saito, Fumito; Ikeda, Reiko

    2005-11-01

    Microbes compete for the environmental niche which is their host. To investigate the effects of a pathogenic bacterium on invasion and colonization by a pathogenic yeast, Cryptococcus neoformans was co-cultured with Staphylococcus aureus. We found that the number of colony forming units of C. neoformans was decreased by Staphylococcus aureus. In contrast, the viability of Candida albicans was not affected. Under the microscope, wild-type C. neoformans cells were shown to be surrounded by S. aureus, while cells of a capsuleless mutant of C. neoformans were not. C. neoformans was not killed when a membrane separated it from S. aureus in co-culture. Killing was confirmed by staining with cyanoditolyl tetrazolium chloride: S. aureus stained red, indicating viability, while C. neojormans did not stain, indicating lethality. The in situ terminal deoxynucleotidyl transferase-mediated dUTR nick end labeling (TUNEL) assay indicated cell death with fragmentation of DNA of C. neoformans. Capsular polysaccharide from C. neoformans inhibited the killing. Treatment of the crude polysaccharide with protease increased the inhibition. The protective activity resided in the glucuronoxylomannan (GXM) fraction, although the concentration required for the inhibition was high. These results suggest that S. aureus kills C. neoformans by a process that involves attachment to the cryptococcal capsule.

  6. Gene content and diversity of the loci encoding biosynthesis of capsular polysaccharides of the 15 serovar reference strains of Haemophilus parasuis.

    PubMed

    Howell, Kate J; Weinert, Lucy A; Luan, Shi-Lu; Peters, Sarah E; Chaudhuri, Roy R; Harris, David; Angen, Oystein; Aragon, Virginia; Parkhill, Julian; Langford, Paul R; Rycroft, Andrew N; Wren, Brendan W; Tucker, Alexander W; Maskell, Duncan J

    2013-09-01

    Haemophilus parasuis is the causative agent of Glässer's disease, a systemic disease of pigs, and is also associated with pneumonia. H. parasuis can be classified into 15 different serovars. Here we report, from the 15 serotyping reference strains, the DNA sequences of the loci containing genes for the biosynthesis of the group 1 capsular polysaccharides, which are potential virulence factors of this bacterium. We contend that these loci contain genes for polysaccharide capsule structures, and not a lipopolysaccharide O antigen, supported by the fact that they contain genes such as wza, wzb, and wzc, which are associated with the export of polysaccharide capsules in the current capsule classification system. A conserved region at the 3' end of the locus, containing the wza, ptp, wzs, and iscR genes, is consistent with the characteristic export region 1 of the model group 1 capsule locus. A potential serovar-specific region (region 2) has been found by comparing the predicted coding sequences (CDSs) in all 15 loci for synteny and homology. The region is unique to each reference strain with the exception of those in serovars 5 and 12, which are identical in terms of gene content. The identification and characterization of this locus among the 15 serovars is the first step in understanding the genetic, molecular, and structural bases of serovar specificity in this poorly studied but important pathogen and opens up the possibility of developing an improved molecular serotyping system, which would greatly assist diagnosis and control of Glässer's disease.

  7. Gene Content and Diversity of the Loci Encoding Biosynthesis of Capsular Polysaccharides of the 15 Serovar Reference Strains of Haemophilus parasuis

    PubMed Central

    Weinert, Lucy A.; Luan, Shi-Lu; Peters, Sarah E.; Chaudhuri, Roy R.; Harris, David; Angen, Øystein; Aragon, Virginia; Parkhill, Julian; Langford, Paul R.; Rycroft, Andrew N.; Wren, Brendan W.; Tucker, Alexander W.; Maskell, Duncan J.

    2013-01-01

    Haemophilus parasuis is the causative agent of Glässer's disease, a systemic disease of pigs, and is also associated with pneumonia. H. parasuis can be classified into 15 different serovars. Here we report, from the 15 serotyping reference strains, the DNA sequences of the loci containing genes for the biosynthesis of the group 1 capsular polysaccharides, which are potential virulence factors of this bacterium. We contend that these loci contain genes for polysaccharide capsule structures, and not a lipopolysaccharide O antigen, supported by the fact that they contain genes such as wza, wzb, and wzc, which are associated with the export of polysaccharide capsules in the current capsule classification system. A conserved region at the 3′ end of the locus, containing the wza, ptp, wzs, and iscR genes, is consistent with the characteristic export region 1 of the model group 1 capsule locus. A potential serovar-specific region (region 2) has been found by comparing the predicted coding sequences (CDSs) in all 15 loci for synteny and homology. The region is unique to each reference strain with the exception of those in serovars 5 and 12, which are identical in terms of gene content. The identification and characterization of this locus among the 15 serovars is the first step in understanding the genetic, molecular, and structural bases of serovar specificity in this poorly studied but important pathogen and opens up the possibility of developing an improved molecular serotyping system, which would greatly assist diagnosis and control of Glässer's disease. PMID:23873912

  8. Capsular Polysaccharide (CPS) Release by Serotype 3 Pneumococcal Strains Reduces the Protective Effect of Anti-Type 3 CPS Antibodies.

    PubMed

    Choi, Eun Hwa; Zhang, Fan; Lu, Ying-Jie; Malley, Richard

    2015-12-16

    The efficacy of the serotype 3 (ST3) pneumococcal conjugate vaccine (PCV) remains unclear. While the synthesis of capsular polysaccharide (CPS) of most serotypes is wzy dependent, the strains of two serotypes, 3 and 37, synthesize CPS by the synthase-dependent pathway, resulting in a polysaccharide that is not covalently linked to peptidoglycan and can be released during growth. We hypothesized that the release of CPS during growth reduces anti-type 3 CPS antibody-mediated protection and may explain the lower efficacy of the type 3 component of PCV than that of other PCVs. The in vitro-released CPS concentrations per 10(7) CFU of ST3 and ST37 strains were significantly higher than those for the ST1, ST4, ST6B, and ST14 strains. Following intraperitoneal (i.p.) injection in mice, blood concentrations of CPS were significantly higher for the ST3 than for the ST4/5 strains. The opsonophagocytic killing assay (OPKA) titer of anti-type 3 CPS antibody was significantly reduced by type 3 CPS, culture supernatant, or serum from Streptococcus pneumoniae ST3 strain WU2-infected mice. Mice were injected with capsule-specific antibodies and challenged i.p. with or without the addition of sterile culture supernatant containing type-specific CPS. The addition of 0.2 μl of culture supernatant from WU2 inhibited passive protection, whereas 100-fold-more culture supernatant from S. pneumoniae ST4 strain TIGR4 was required for the inhibition of protection. We conclude that released type 3 CPS interferes with antibody-mediated killing and protection by anti-CPS antibodies. The relative failure of ST3 PCV may be due to CPS release, suggesting that alternative immunization approaches for ST3 may be necessary.

  9. Capsular Polysaccharide (CPS) Release by Serotype 3 Pneumococcal Strains Reduces the Protective Effect of Anti-Type 3 CPS Antibodies

    PubMed Central

    Choi, Eun Hwa; Zhang, Fan; Lu, Ying-Jie

    2015-01-01

    The efficacy of the serotype 3 (ST3) pneumococcal conjugate vaccine (PCV) remains unclear. While the synthesis of capsular polysaccharide (CPS) of most serotypes is wzy dependent, the strains of two serotypes, 3 and 37, synthesize CPS by the synthase-dependent pathway, resulting in a polysaccharide that is not covalently linked to peptidoglycan and can be released during growth. We hypothesized that the release of CPS during growth reduces anti-type 3 CPS antibody-mediated protection and may explain the lower efficacy of the type 3 component of PCV than that of other PCVs. The in vitro-released CPS concentrations per 107 CFU of ST3 and ST37 strains were significantly higher than those for the ST1, ST4, ST6B, and ST14 strains. Following intraperitoneal (i.p.) injection in mice, blood concentrations of CPS were significantly higher for the ST3 than for the ST4/5 strains. The opsonophagocytic killing assay (OPKA) titer of anti-type 3 CPS antibody was significantly reduced by type 3 CPS, culture supernatant, or serum from Streptococcus pneumoniae ST3 strain WU2-infected mice. Mice were injected with capsule-specific antibodies and challenged i.p. with or without the addition of sterile culture supernatant containing type-specific CPS. The addition of 0.2 μl of culture supernatant from WU2 inhibited passive protection, whereas 100-fold-more culture supernatant from S. pneumoniae ST4 strain TIGR4 was required for the inhibition of protection. We conclude that released type 3 CPS interferes with antibody-mediated killing and protection by anti-CPS antibodies. The relative failure of ST3 PCV may be due to CPS release, suggesting that alternative immunization approaches for ST3 may be necessary. PMID:26677201

  10. Fur regulation of the capsular polysaccharide biosynthesis and iron-acquisition systems in Klebsiella pneumoniae CG43.

    PubMed

    Lin, Ching-Ting; Wu, Chien-Chen; Chen, Yu-Sheng; Lai, Yi-Chyi; Chi, Chia; Lin, Jing-Ciao; Chen, Yeh; Peng, Hwei-Ling

    2011-02-01

    The ferric uptake regulator Fur has been reported to repress the expression of rmpA, a regulatory gene for the mucoid phenotype, leading to decreased capsular polysaccharide (CPS) biosynthesis in Klebsiella pneumoniae CG43. Here, quantitative real-time PCR (qRT-PCR) analyses and electrophoretic mobility shift assays showed that Fur also repressed the expression of the CPS regulatory genes rmpA2 and rcsA. Interestingly, deletion of rmpA or rcsA but not rmpA2 from the Δfur strain was able to suppress the deletion effect of Fur. The availability of extracellular iron affected the amount of CPS, suggesting that Fur regulates CPS biosynthesis in an Fe(II)-dependent manner. Increased production of siderophores was observed in the Δfur strain, suggesting that uptake of extracellular iron in K. pneumoniae is regulated by Fur. Fur titration assays and qRT-PCR analyses demonstrated that at least six of the eight putative iron-acquisition systems, identified by a blast search in the contig database of K. pneumoniae CG43, were directly repressed by Fur. We conclude that Fur has a dual role in the regulation of CPS biosynthesis and iron acquisition in K. pneumoniae.

  11. Capsular polysaccharides facilitate enhanced iron acquisition by the colonial cyanobacterium Microcystis sp. isolated from a freshwater lake.

    PubMed

    Li, Zheng-Ke; Dai, Guo-Zheng; Juneau, Philippe; Qiu, Bao-Sheng

    2016-02-01

    Microcystis sp., especially in its colonial form, is a common dominant species during cyanobacterial blooms in many iron-deficient water bodies. It is still not entirely clear, however, how the colonial forms of Microcystis acclimate to iron-deficient habitats, and the responses of unicellular and colonial forms to iron-replete and iron-deficient conditions were examined here. Growth rates and levels of photosynthetic pigments declined to a greater extent in cultures of unicellular Microcystis than in cultures of the colonial form in response to decreasing iron concentrations, resulting in the impaired photosynthetic performance of unicellular Microcystis as compared to colonial forms as measured by variable fluorescence and photosynthetic oxygen evolution. These results indicate that the light-harvesting ability and photosynthetic capacity of colonial Microcystis was less affected by iron deficiency than the unicellular form. The carotenoid contents and nonphotochemical quenching of colonial Microcystis were less reduced than those of the unicellular form under decreasing iron concentrations, indicating that the colonial morphology enhanced photoprotection and acclimation to iron-deficient conditions. Furthermore, large amounts of iron were detected in the capsular polysaccharides (CPS) of the colonies, and more iron was found to be attached to the colonial Microcystis CPS under decreasing iron conditions as compared to unicellular cultures. These results demonstrated that colonial Microcystis can acclimate to iron deficiencies better than the unicellular form, and that CPS plays an important role in their acclimation advantage in iron-deficient waters.

  12. Humoral immune response of a pneumococcal conjugate vaccine: capsular polysaccharide serotype 14-Lysine modified PspA.

    PubMed

    Santamaria, Raquel; Goulart, Cibelly; Perciani, Catia T; Barazzone, Giovana C; Carvalho, Rimenys; Gonçalves, Viviane M; Leite, Luciana C C; Tanizaki, Martha M

    2011-11-03

    Polysaccharide-protein conjugates are so far the current antigens used for pneumococcal vaccines for children under 2 years of age. In this study, pneumococcal surface protein A (PspA) was used as a carrier protein for pneumococcal capsular polysaccharide serotype 14 as an alternative to broaden the vaccine coverage. PspA was modified by reductive amination with formaldehyde in order to improve the specificity of the reaction between protein and polysaccharide, inhibiting polymerization and the gel formation reaction. In the synthesis process, the currently used activator, 1-[3-(dimethylamine)propyl]-3-ethylcarbodiimide hydrochloride (EDAC) was substituted for 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM). BALB/c mice were immunized with either the PS14-mPspA conjugate or the co-administered components in a three dose regimen and sera from the immunized animals were assayed for immunity induced against both antigens: PS14 and mPspA. Modification of more than 70% of lysine residues from PspA (mPspA) did not interfere in the immune response as evaluated by the anti-PspA titer and C3 complement deposition assay. Sera of mice immunized with conjugated PS14-mPspA showed similar IgG titers, avidity and isotype profile as compared to controls immunized with PspA or mPspA alone. The complement deposition was higher in the sera of mice immunized with the conjugate vaccine and the opsonophagocytic activity was similar for both sera. Conjugation improved the immune response against PS14. The anti PS14 IgG titer was higher in sera of mice immunized with the conjugate than with co-administered antigens and presented an increased avidity index, induction of a predominant IgG1 isotype and increased complement deposition on a bacteria with a surface serotype 14. These results strongly support the use of PspA as carrier in a conjugate vaccine where both components act as antigens.

  13. Evidence for a LOS and a capsular polysaccharide in Capnocytophaga canimorsus

    PubMed Central

    Renzi, Francesco; Ittig, Simon J.; Sadovskaya, Irina; Hess, Estelle; Lauber, Frederic; Dol, Melanie; Shin, Hwain; Mally, Manuela; Fiechter, Chantal; Sauder, Ursula; Chami, Mohamed; Cornelis, Guy R.

    2016-01-01

    Capnocytophaga canimorsus is a dog’s and cat’s oral commensal which can cause fatal human infections upon bites or scratches. Infections mainly start with flu-like symptoms but can rapidly evolve in fatal septicaemia with a mortality as high as 40%. Here we present the discovery of a polysaccharide capsule (CPS) at the surface of C. canimorsus 5 (Cc5), a strain isolated from a fulminant septicaemia. We provide genetic and chemical data showing that this capsule is related to the lipooligosaccharide (LOS) and probably composed of the same polysaccharide units. A CPS was also found in nine out of nine other strains of C. canimorsus. In addition, the genomes of three of these strains, sequenced previously, contain genes similar to those encoding CPS biosynthesis in Cc5. Thus, the presence of a CPS is likely to be a common property of C. canimorsus. The CPS and not the LOS confers protection against the bactericidal effect of human serum and phagocytosis by macrophages. An antiserum raised against the capsule increased the killing of C. canimorsus by human serum thus showing that anti-capsule antibodies have a protective role. These findings provide a new major element in the understanding of the pathogenesis of C. canimorsus. PMID:27974829

  14. New insight into chondroitin and heparosan-like capsular polysaccharide synthesis by profiling of the nucleotide sugar precursors

    PubMed Central

    di Lauro, Irene; Di Nuzzo, Rosaria; De Rosa, Mario; Schiraldi, Chiara

    2017-01-01

    Escherichia coli K4 and K5 capsular polysaccharides (K4 and K5 CPSs) have been used as starting material for the biotechnological production of chondroitin sulfate (CS) and heparin (HP) respectively. The CPS covers the outer cell wall but in late exponential or stationary growth phase it is released in the surrounding medium. The released CPS concentration was used, so far, as the only marker to connect the strain production ability to the different cultivation conditions employed. Determining also the intracellular UDP-sugar precursor concentration variations, during the bacterial growth, and correlating it with the total CPS production (as sum of the inner and the released ones), could help to better understand the chain biosynthetic mechanism and its bottlenecks. In the present study, for the first time, a new capillary electrophoresis method was set up to simultaneously analyse the UDP-glucose (UDP-Glc), UDP-galactose (UDP-Gal), UDP-N-acetylgalactosamine (UDP-GalNAc), UDP-N-acetylglucosamine (UDP-GlcNAc) and UDP-glucuronic acid (UDP-GlcA) and the inner CPS portion, extracted at the same time from the bacterial biomasses; separation was performed at 18°C and 18 kV with a borate-based buffer and detection at 200 nm. The E. coli K4 and K5 UDP-sugar pools were profiled, for the first time, at different time points of shake flask growths on a glycerol-containing medium and on the same medium supplemented with the monosaccharide precursors of the CPSs: their concentrations varied from 0.25 to 11 μM·gcdw−1, according to strain, the type of precursor, the growth phase and the cultivation conditions and their availability dramatically influenced the total CPS produced. PMID:28104792

  15. Sub-MICs of Azithromycin Decrease Biofilm Formation of Streptococcus suis and Increase Capsular Polysaccharide Content of S. suis

    PubMed Central

    Yang, Yan-Bei; Chen, Jian-Qing; Zhao, Yu-Lin; Bai, Jing-Wen; Ding, Wen-Ya; Zhou, Yong-Hui; Chen, Xue-Ying; Liu, Di; Li, Yan-Hua

    2016-01-01

    Streptococcus suis (S. suis) caused serious disease symptoms in humans and pigs. S. suis is able to form thick biofilms and this increases the difficulty of treatment. After growth with 1/2 minimal inhibitory concentration (MIC) of azithromycin, 1/4 MIC of azithromycin, or 1/8 MIC of azithromycin, biofilm formation of S. suis dose-dependently decreased in the present study. Furthermore, scanning electron microscopy analysis revealed the obvious effect of azithromycin against biofilm formation of S. suis. Especially, at two different conditions (1/2 MIC of azithromycin non-treated cells and treated cells), we carried out comparative proteomic analyses of cells by using iTRAQ technology. Finally, the results revealed the existence of 19 proteins of varying amounts. Interestingly, several cell surface proteins (such as ATP-binding cassette superfamily ATP-binding cassette transporter (G7SD52), CpsR (K0FG35), Cps1/2H (G8DTL7), CPS16F (E9NQ13), putative uncharacterized protein (G7SER0), NADP-dependent glyceraldehyde-3-phosphate dehydrogenase (G5L259), putative uncharacterized protein (G7S2D6), amino acid permease (B0M0G6), and NsuB (G5L351)) were found to be implicated in biofilm formation. More importantly, we also found that azithromycin affected expression of the genes cps1/2H, cpsR and cps16F. Especially, after growth with 1/2 MIC of azithromycin and 1/4 MIC of azithromycin, the capsular polysaccharide content of S. suis was significantly higher. PMID:27812354

  16. Application of glyco-blotting for identification of structures of polysaccharides causing membrane fouling in a pilot-scale membrane bioreactor treating municipal wastewater.

    PubMed

    Kimura, Katsuki; Nishimura, Shin-Ichiro; Miyoshi, Risho; Hoque, Asiful; Miyoshi, Taro; Watanabe, Yoshimasa

    2015-03-01

    A new approach for the analysis of polysaccharides in membrane bioreactor (MBR) is proposed in this study. Enrichment of polysaccharides by glyco-blotting, in which polysaccharides are specifically collected via interactions between the aldehydes in the polysaccharides and aminooxy groups on glycoblotting beads, enabled MALDI-TOF/MS analysis at a high resolution. Structures of polysaccharides extracted from fouled membranes used in a pilot-scale MBR treating municipal wastewater and those in the supernatant of the mixed liquor suspension in the MBR were investigated. It was found that the overlap between polysaccharides found in the supernatants and those extracted from the fouled membrane was rather limited, suggesting that polysaccharides that dominate in supernatants may not be important in membrane fouling in MBRs. Analysis using a bacterial carbohydrate database suggested that capsular polysaccharides (CPS) and/or lipo-polysaccharides (LPS) produced by gram-negative bacteria are key players in the evolution of membrane fouling in MBRs.

  17. Synthesis of di- and tri-saccharide fragments of Salmonella typhi Vi capsular polysaccharide and their zwitterionic analogues.

    PubMed

    Fusari, Matteo; Fallarini, Silvia; Lombardi, Grazia; Lay, Luigi

    2015-12-01

    Zwitterionic polysaccharides (ZPS) behave like traditional T cell-dependent antigens, suggesting the design of new classes of vaccines alternative to currently used glycoconjugates and based on the artificial introduction of a zwitterionic charge motif onto the carbohydrate structure of pathogen antigens. Here we report the new synthesis and antigenic evaluation of di-/tri-saccharide fragments of Salmonella typhi Vi polysaccharide, as well as of their corresponding zwitterionic analogues. Our strategy is based on versatile intermediates enabling chain elongation either by iterative single monomer attachment or by faster and more flexible approach using disaccharide donors. The effect of structural modifications of the synthetic compounds on antigenic properties was evaluated by competitive ELISA. All the oligosaccharides were recognized by specific anti-Vi polyclonal antibodies in a concentration-dependent manner, and the introduction of a zwitterionic motif into the synthetic molecules did not prevent the binding.

  18. Group B Streptococcus Capsular Polysaccharide-Cholera Toxin B Subunit Conjugate Vaccines Prepared by Different Methods for Intranasal Immunization

    PubMed Central

    Shen, Xuzhuang; Lagergård, Teresa; Yang, Yonghong; Lindblad, Marianne; Fredriksson, Margareta; Holmgren, Jan

    2001-01-01

    Group B Streptococcus (GBS) type III capsular polysaccharide (CPS III) was conjugated to recombinant cholera toxin B subunit (rCTB) using three different methods which employed (i) cystamine and N-succinimidyl-3-(2-pyridyldithio)propionate (SPDP), (ii) carbodiimide with adipic acid dihydrazide (ADH) as a spacer, or (iii) reductive amination (RA). The CPS III-rCTB conjugates were divided into large- and small-molecular-weight (Mr) fractions, and the immunogenicities of the different preparations after intranasal (i.n.) immunization were studied in mice. Both large- and small-Mr conjugates of CPS III-rCTBRA or CPS III-rCTBADH induced high, almost comparable levels of CPS-specific immunoglobulin G (IgG) in serum, lungs, and vagina that were generally superior to those obtained with CPS III-rCTBSPDP conjugates or a CPS III and rCTB mixture. However, the smaller-Mr conjugates of CPS III-rCTBRA or CPS III-rCTBADH in most cases elicited a lower anti-CPS IgA immune response than the large-Mr conjugates, and the highest anti-CPS IgA titers in both tissues and serum were obtained with the large-Mr CPS III-rCTBRA conjugate. Serum IgG anti-CPS titers induced by the CPS III-rCTBRA conjugate had high levels of specific IgG1, IgG2a, IgG2b, and IgG3 antibodies. Based on the effectiveness of RA for coupling CPS III to rCTB, RA was also tested for conjugating GBS CPS Ia with rCTB. As for the CPS III-rCTB conjugates, the immunogenicity of CPS Ia was greatly increased by conjugation to rCTB. Intranasal immunization with a combination of CPS Ia-rCTB and CPS III-rCTB conjugates was shown to induce anti-CPS Ia and III immune responses in serum and lungs that were fully comparable with the responses to immunization with the monovalent CPS Ia-rCTB or CPS III-rCTB conjugates. These results suggest that the GBS CPS III-rCTB and CPS Ia-rCTB conjugates prepared by the RA method may be used in bivalent and possibly also in multivalent mucosal GBS conjugate vaccines. PMID:11119518

  19. A Staphylococcus aureus capsular polysaccharide (CP) vaccine and CP-specific antibodies protect mice against bacterial challenge.

    PubMed Central

    Fattom, A I; Sarwar, J; Ortiz, A; Naso, R

    1996-01-01

    The efficacy of capsular polysaccharide (CP)-specific antibodies elicited by active immunization with vaccines composed of Staphylococcus aureus types 5 and 8 CP linked to Pseudomonas aeruginosa exoprotein A or with immune immunoglobulin G (I-IgG) obtained from vaccinated plasma donors was tested in lethal and sublethal bacterial mouse challenge models. A dose of 2 x 10(5) CFU of S. aureus type 5 CP per mouse administered intraperitoneally (i.p.) with 5% hog mucin was found to cause 80 to 100% mortality in BALB/c mice within 2 to 5 days. Mice passively immunized i.p. 24 h earlier or subcutaneously 48 h earlier with 0.5 ml of I-IgG showed significantly higher average survival rates than animals receiving standard IgG or saline (P < 0.01) following the bacterial challenge. Animals actively immunized with the monovalent type 5 CP-P. aeruginosa exoprotein A conjugate showed a survival rate of 73% compared with 13% in phosphate-buffered saline-immunized animals. The prechallenge geometric mean titer of type 5 CP antibodies in animals that died was significantly (P < 0.05) lower than that of animals which survived the challenge (95.7 versus 223.6 micrograms/ml, respectively). The IgG was further evaluated in mice challenged i.p. with a sublethal dose of 5 x 10(4) CFU per mouse. Serial blood counts were performed on surviving animals at 6, 12, 24, and 48 h. Surviving animals were sacrificed at 72 h, and bacterial counts were performed on their kidneys, livers, and peritoneal lavage fluids. Animals receiving I-IgG had lower bacterial counts in blood samples and lower bacterial densities in kidneys, livers, and peritoneal lavage samples than mice immunized with standard IgG (P < 0.05). These data suggest that S. aureus type 5 CP antibodies induced by active immunization or administered by passive immunization confer protection against S. aureus infections. PMID:8613375

  20. Cloning of type 8 capsule genes and analysis of gene clusters for the production of different capsular polysaccharides in Staphylococcus aureus.

    PubMed

    Sau, S; Lee, C Y

    1996-04-01

    Eleven serotypes of capsular polysaccharide from Staphylococcus aureus have been reported. We have previously cloned a cluster of type 1 capsule (cap1) genes responsible for type 1 capsular polysaccharide biosynthesis in S. aureus M. To clone the type 8 capsule (cap8) genes, a plasmid library of type 8 strain Becker was screened with a labelled DNA fragment containing the cap1 genes under low-stringency conditions. One recombinant plasmid containing a 14-kb insert was chosen for further study and found to complement 14 of the 18 type 8 capsule-negative (Cap8-) mutants used in the study. Additional library screening, subcloning, and complementation experiments showed that all of the 18 Cap8- mutants were complemented by DNA fragments derived from a 20.5-kb contiguous region of the Becker chromosome. The mutants were mapped into six complementation groups, indicating that the cap8 genes are clustered. By Southern hybridization analyses under high-stringency conditions, we found that DNA fragments containing the cap8 gene cluster show extensive homology with all 17 strains tested, including type 1 strains. By further Southern analyses and cloning of the cap8-related homolog from strain M, we show that strain M carries an additional capsule gene cluster different from the cap1 gene cluster. In addition, by using DNA fragments containing different regions of the cap8 gene cluster as probes to hybridize DNA from different strains, we found that the central region of the cap8 gene cluster hybridizes only to DNAs from certain strains tested whereas the flanking regions hybridize to DNAs of all strains tested. Thus, the cap8 gene clusters and its closely related homologs are likely to have organizations similar to those of the encapsulation genes of other bacterial systems.

  1. Regulated expression of polysaccharide utilization and capsular biosynthesis loci in biofilm and planktonic Bacteroides thetaiotaomicron during growth in chemostats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bacteroides thetaiotaomicron is a prominent member of the human distal gut microbiota that specializes in breaking down diet and host-derived polysaccharides. While polysaccharide utilization has been well studied in B. thetaiotaomicron, other aspects of its behavior are less well characterized, in...

  2. Vibrio cholerae O139 Conjugate Vaccines: Synthesis and Immunogenicity of V. cholerae O139 Capsular Polysaccharide Conjugates with Recombinant Diphtheria Toxin Mutant in Mice

    PubMed Central

    Kossaczka, Zuzana; Shiloach, Joseph; Johnson, Virginia; Taylor, David N.; Finkelstein, Richard A.; Robbins, John B.; Szu, Shousun C.

    2000-01-01

    Epidemiologic and experimental data provide evidence that a critical level of serum immunoglobulin G (IgG) antibodies to the surface polysaccharide of Vibrio cholerae O1 (lipopolysaccharide) and of Vibrio cholerae O139 (capsular polysaccharide [CPS]) is associated with immunity to the homologous pathogen. The immunogenicity of polysaccharides, especially in infants, may be enhanced by their covalent attachment to proteins (conjugates). Two synthetic schemes, involving 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) as activating agents, were adapted to prepare four conjugates of V. cholerae O139 CPS with the recombinant diphtheria toxin mutant, CRMH21G. Adipic acid dihydrazide was used as a linker. When injected subcutaneously into young outbred mice by a clinically relevant dose and schedule, these conjugates elicited serum CPS antibodies of the IgG and IgM classes with vibriocidal activity to strains of capsulated V. cholerae O139. Treatment of these sera with 2-mercaptoethanol (2-ME) reduced, but did not eliminate, their vibriocidal activity. These results indicate that the conjugates elicited IgG with vibriocidal activity. Conjugates also elicited high levels of serum diphtheria toxin IgG. Convalescent sera from 20 cholera patients infected with V. cholerae O139 had vibriocidal titers ranging from 100 to 3,200: absorption with the CPS reduced the vibriocidal titer of all sera to ≤50. Treatment with 2-ME reduced the titers of 17 of 20 patients to ≤50. These data show that, like infection with V. cholerae O1, infection with V. cholerae O139 induces vibriocidal antibodies specific to the surface polysaccharide of this bacterium (CPS) that are mostly of IgM class. Based on these data, clinical trials with the V. cholerae O139 CPS conjugates with recombinant diphtheria toxin are planned. PMID:10948122

  3. Comparison of radioimmunoassay and enzyme-linked immunosorbent assay in measurement of antibodies to Neisseria meningitidis group A capsular polysaccharide.

    PubMed Central

    Beuvery, E C; Kayhty, M H; Leussink, A B; Kanhai, V

    1984-01-01

    Antibodies to meningococcal group A polysaccharide were determined by radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) in serum samples from 16 adults vaccinated with bivalent meningococcal group A and C polysaccharide vaccine. The specific antibody levels in the serum samples were expressed as micrograms of antibody protein per milliliter of serum. For RIA the polysaccharide was radiolabeled extrinsically with 125I. Both native polysaccharide and polysaccharide labeled with 127I were used in ELISA. Because these antigens gave similar results, it can be concluded that the introduction of tyramine and iodine by the labeling procedure did not alter the antigenic activity of the polysaccharide. The reproducibility of RIA was clearly better than that of ELISA. The antibody levels detected by the methods were equal, which means that ELISA can be used satisfactorily to measure antibodies to meningococcal group A polysaccharide quantitatively. Some discrepant results were found due to an underestimation of immunoglobulin M antibodies in ELISA. This was shown by a correlation test in which a weakly significant negative correlation was found between the immunoglobulin M antibody level/immunoglobulin G antibody level ratio and the RIA antibody level/ELISA antibody level ratio. PMID:6436314

  4. Monoclonal antibodies specific for immunorecessive epitopes of glucuronoxylomannan, the major capsular polysaccharide of Cryptococcus neoformans, reduce serotype bias in an immunoassay for cryptococcal antigen.

    PubMed

    Percival, Ann; Thorkildson, Peter; Kozel, Thomas R

    2011-08-01

    Immunoassay for detection of glucuronoxylomannan (GXM), the major capsular polysaccharide of Cryptococcus neoformans, is an important tool for diagnosis of cryptococcosis. However, immunoassays that are based solely or in part on detection with polyclonal antibodies may show serotype bias in detection of GXM, particularly limited sensitivity for serotype C. In this study, we describe detection of GXM in an antigen capture sandwich enzyme-linked immunosorbent assay (ELISA) that used a cocktail of two monoclonal antibodies (MAbs). MAb F12D2 was previously produced by immunization with GXM that had been treated to remove O-acetyl groups, a major source of serotype specificity. MAb F12D2 has a high degree of reactivity with GXM of serotypes A, B, C, and D, but the reactivity with serotype D was less than was found with other MAbs. MAb 339 is highly reactive with GXM of serotypes A and D. Use of a combination of the two MAbs produced an immunoassay that had the best properties of both MAbs, including good reactivity with serotype C, which is an emerging threat in sub-Saharan Africa. These results suggest that next-generation immunoassays for diagnosis of cryptococcosis may be formulated by (i) use of immunization and hybridoma screening strategies that are designed to prospectively meet the needs of immunoassay performance and (ii) careful selection of MAbs that span the expected polysaccharide serotypes in the subject patient population.

  5. Phase II, randomized, multicenter, double-blind, placebo-controlled trial of a polyclonal anti-Staphylococcus aureus capsular polysaccharide immune globulin in treatment of Staphylococcus aureus bacteremia.

    PubMed

    Rupp, Mark E; Holley, H Preston; Lutz, Jon; Dicpinigaitis, Peter V; Woods, Christopher W; Levine, Donald P; Veney, Naomi; Fowler, Vance G

    2007-12-01

    New treatment modalities are needed for the treatment of infections due to multidrug-resistant Staphylococcus aureus. S. aureus capsular polysaccharide immune globulin (Altastaph) is a polyclonal immune globulin preparation that is being developed as adjunctive therapy for persons with S. aureus infections complicated by bacteremia. In a phase II, multicenter, randomized, double-blind, placebo-controlled trial, 40 subjects with documented S. aureus bacteremia received standard therapy plus either Altastaph at 200 mg/kg of body weight in each of two infusions 24 h apart or placebo. During the 42-day observation period, antibody pharmacokinetics and safety were the primary characteristics studied. Information regarding the resolution of bacteremia and fever was also analyzed. Anti-type-5 and anti-type-8 capsular antibody levels peaked after the second infusion at 550 mug/ml and 419 mug/ml, respectively, and remained above 100 mug/ml at day 28. A total of 316 adverse events were noted in 39 of 40 subjects. Infusion-related adverse events in Altastaph recipients were infrequent and similar to those among recipients of commercial intravenously administered immunoglobulin G products. Five of 21 (23%) subjects in the Altastaph group died, whereas 2 of 18 (11%) subjects in the placebo group died (P = 0.42). Compared to the control patients, the Altastaph recipients had a shorter median time to the resolution of fever (2 days and 7 days, respectively; P = 0.09) and a shorter length of hospital stay (9 days and 14 days, respectively; P = 0.03). However, these findings are exploratory, and there were few differences in the other variables measured. High levels of opsonizing antibodies were maintained for the initial 4 weeks. Although the study was not powered to show efficacy, these preliminary findings and safety profile suggest that Altastaph may be an effective adjunct to antibiotics and warrants further investigation (ClinicalTrials.gov number NCT00063089).

  6. Recognition of riboflavin and the capsular polysaccharide of Haemophilus influenzae type b by antibodies generated to the haptenic epitope D-ribitol.

    PubMed

    Ravi, G; Venkatesh, Yeldur P

    2014-04-01

    D-Ribitol, a five-carbon sugar alcohol, is an important metabolite in the pentose phosphate pathway; it is an integral part of riboflavin (vitamin B2) and cell wall polysaccharides in most Gram-positive and a few Gram-negative bacteria. Antibodies specific to D-ribitol were generated in New Zealand white rabbits by using reductively aminated D-ribose-BSA conjugate as the immunogen. MALDI-TOF and amino group analyses of ribitol-BSA conjugate following 120 h reaction showed ~27-30 mol of ribitol conjugated per mole BSA. The presence of sugar alcohol in the conjugates was also confirmed by an increase in molecular mass and a positive periodic acid-Schiff staining in SDS-PAGE. Caprylic acid precipitation of rabbit serum followed by hapten affinity chromatography on ribitol-KLH-Sepharose CL-6B resulted in pure ribitol-specific antibodies (~45-50 μg/mL). The affinity constant of ribitol antibodies was found to be 2.9 × 10(7) M(-1) by non-competitive ELISA. Ribitol antibodies showed 100% specificity towards ribitol, ~800% cross-reactivity towards riboflavin, 10-15% cross-reactivity with sorbitol, xylitol and mannitol, and 5-7% cross-reactivity with L-arabinitol and meso-erythritol. The specificity of antibody to ribitol was further confirmed by its low cross-reactivity (0.4%) with lumichrome. Antibodies to D-ribitol recognized the purified capsular polysaccharide of Haemophilus influenzae type b, which could be specifically inhibited by ribitol. In conclusion, antibodies specific to D-ribitol have been generated and characterized, which have potential applications in the detection of free riboflavin and ribitol in biological samples, as well as identification of cell-surface macromolecules containing ribitol.

  7. Capsular Polysaccharide of Mycoplasma ovipneumoniae Induces Sheep Airway Epithelial Cell Apoptosis via ROS-Dependent JNK/P38 MAPK Pathways

    PubMed Central

    Jiang, Zhongjia; Song, Fuyang; Li, Yanan; Xue, Di; Zhao, Ning; Zhang, Jiamei; Deng, Guangcun; Li, Min

    2017-01-01

    In an attempt to better understand the pathogen-host interaction between invading Mycoplasma ovipneumoniae (M. ovipneumoniae) and sheep airway epithelial cells, biological effects and possible molecular mechanism of capsular polysaccharide of M. ovipneumoniae (CPS) in the induction of cell apoptosis were explored using sheep bronchial epithelial cells cultured in air-liquid interface (ALI). The CPS of M. ovipneumoniae was first isolated and purified. Results showed that CPS had a cytotoxic effect by disrupting the integrity of mitochondrial membrane, accompanied with an increase of reactive oxygen species and decrease of mitochondrial membrane potential (ΔΨm). Of importance, the CPS exhibited an ability to induce caspase-dependent cell apoptosis via both intrinsic and extrinsic apoptotic pathways. Mechanistically, the CPS induced extrinsic cell apoptosis by upregulating FAS/FASL signaling proteins and cleaved-caspase-8 and promoted a ROS-dependent intrinsic cell apoptosis by activating a JNK and p38 signaling but not ERK1/2 signaling of mitogen-activated protein kinases (MAPK) pathways. These findings provide the first evidence that CPS of M. ovipneumoniae induces a caspase-dependent apoptosis via both intrinsic and extrinsic apoptotic pathways in sheep bronchial epithelial cells, which may be mainly attributed by a ROS-dependent JNK and p38 MAPK signaling pathways. PMID:28367270

  8. Comparative characterization of the virulence gene clusters (lipooligosaccharide [LOS] and capsular polysaccharide [CPS]) for Campylobacter coli, Campylobacter jejuni subsp. jejuni and related Campylobacter species.

    PubMed

    Richards, Vincent P; Lefébure, Tristan; Pavinski Bitar, Paulina D; Stanhope, Michael J

    2013-03-01

    Campylobacter jejuni subsp. jejuni and Campylobacter coli are leading causes of gastroenteritis, with virulence linked to cell surface carbohydrate diversity. Although the associated gene clusters are well studied for C. jejuni subsp. jejuni, C. coli has been largely neglected. Here we provide comparative analysis of the lipooligosaccharide (LOS) and capsular polysaccharide (CPS) gene clusters, using genome and cluster sequence data for 36 C. coli strains, 67 C. jejuni subsp. jejuni strains and ten additional Campylobacter species. Similar to C. jejuni subsp. jejuni, C. coli showed high LOS/CPS gene diversity, with each cluster delineated into eight gene content classes. This diversity was predominantly due to extensive gene gain/loss, with the lateral transfer of genes likely occurring both within and between species and also between the LOS and CPS. Additional mechanisms responsible for LOS/CPS diversity included phase-variable homopolymeric repeats, gene duplication/inactivation, and possibly host environment selection pressure. Analyses also showed that (i) strains of C. coli and Campylobacter upsaliensis possessed genes homologous to the sialic acid genes implicated in the neurological disorder Guillain-Barré syndrome (GBS), and (ii) C. coli LOS classes were differentiated between bovine and poultry hosts, potentially aiding post infection source tracking.

  9. Expression of type 8 capsular polysaccharide and production of toxic shock syndrome toxin 1 are associated among vaginal isolates of Staphylococcus aureus.

    PubMed Central

    Lee, J C; Liu, M J; Parsonnet, J; Arbeit, R D

    1990-01-01

    A colony immunoblot method was developed for serotyping the capsular polysaccharides expressed by Staphylococcus aureus isolates. The method was rapid and specific and was performed with either polyclonal or monoclonal antibodies specific for each of the capsule types. S. aureus isolates were obtained from patients with toxic shock syndrome (TSS) or other staphylococcal infections and from asymptomatic women with vaginal colonization. Among the vaginal isolates of S. aureus, expression of the type 8 capsule was significantly (P less than 0.001) more frequent among strains that produced TSS toxin 1 (TSST-1) than it was among TSST-1-negative strains. In contrast, the frequency of type 8 capsule expression was similar among both TSST-1-positive and -negative strains of S. aureus from patients with nonvaginal TSS. When all vaginal and nonvaginal isolates were compared, TSST-1-negative S. aureus strains were equally distributed among the type 5 and 8 and nontypeable capsule groups, whereas TSST-1-positive strains were predominantly capsule type 8. Images PMID:2279990

  10. CpsR, a GntR family regulator, transcriptionally regulates capsular polysaccharide biosynthesis and governs bacterial virulence in Streptococcus pneumoniae

    PubMed Central

    Wu, Kaifeng; Xu, Hongmei; Zheng, Yuqiang; Wang, Libin; Zhang, Xuemei; Yin, Yibing

    2016-01-01

    Transcriptional regulation of capsule expression is critical for pneumococcal transition from carriage to infection, yet the underlying mechanism remains incompletely understood. Here, we describe the regulation of capsular polysaccharide, one of the most important pneumococcal virulence factor by a GntR family regulator, CpsR. Electrophoretic mobility-shift assays have shown the direct interaction between CpsR and the cps promoter (cpsp), and their interaction could be competitively interfered by glucose. DNase I footprinting assays localized the binding site to a region −146 to −114 base pairs relative to the transcriptional start site of the cps locus in S. pneumoniae D39. We found that CpsR negatively controlled the transcription of the cps locus and hence CPS production, which was confirmed by fine-tuning expression of CpsR in a ΔcpsR complemented strain. Increased expression of CpsR in complemented strain led to a decreased resistance to the whole-blood-mediated killing, suggesting a protective role for CpsR-cpsp interaction in the establishment of invasive infection. Finally, animal experiments showed that CpsR-cpsp interaction was necessary for both pneumococcal colonization and invasive infection. Taken together, our results provide a thorough insight into the regulation of capsule production mediated by CpsR and its important roles in pneumococcal pathogenesis. PMID:27386955

  11. ComE, an Essential Response Regulator, Negatively Regulates the Expression of the Capsular Polysaccharide Locus and Attenuates the Bacterial Virulence in Streptococcus pneumoniae.

    PubMed

    Zheng, Yuqiang; Zhang, Xuemei; Wang, Xiaofang; Wang, Libin; Zhang, Jinghui; Yin, Yibing

    2017-01-01

    The capsular polysaccharide (CPS) of Streptococcus pneumoniae is the main virulence factors required for effective colonization and invasive disease. The capacity to regulate CPS production at the transcriptional level is critical for the survival of S. pneumoniae in different host niches, but little is known about the transcription regulators of cps locus. In the present study, we isolated and identified the response regulator ComE, the master competence switch in transformation of S. pneumoniae, as a transcriptional regulator of cps locus by DNA affinity chromatography-pulldown, MALDI-TOF mass spectrometry (MS) and electrophoretic mobility shift assay (EMSA). Our results showed that phosphorylated mimetic of ComE (ComE(D58E)) bound specifically to the cps locus prompter in vitro, and phosphorylated ComE negatively impacted both cps locus transcription and CPS production attenuating the pneumococcal virulence in vivo. Compared with D39-WT strain, D39ΔcomE mutant exhibited much thicker capsule, attenuated nasopharyngeal colonization and enhanced virulence in both pneumonia and bacteremia models of Balb/c mice. Furthermore, it was demonstrated that CSP-ComD/E competence system involved in regulating negatively the CPS production during the progress of transformation in D39. Our CSP1 induction experiment results showed that the expression of ComE in D39-WT strain increased powerfully by 120% after 10 min of CSP1 induction, but the CPS production in D39-WT strain decreased sharply by 67.1% after 15 min of CSP1 induction. However, the CPS production in D39ΔcomE mutant was almost constant during the whole stage of induction. Additionally, we found that extracellular glucose concentration could affect both the expression of ComE and CPS production of D39 in vitro. Taken together, for the first time, we report that ComE, as a transcriptional regulator of cps locus, plays an important role in transcriptional regulation of cps locus and capsular production level.

  12. ComE, an Essential Response Regulator, Negatively Regulates the Expression of the Capsular Polysaccharide Locus and Attenuates the Bacterial Virulence in Streptococcus pneumoniae

    PubMed Central

    Zheng, Yuqiang; Zhang, Xuemei; Wang, Xiaofang; Wang, Libin; Zhang, Jinghui; Yin, Yibing

    2017-01-01

    The capsular polysaccharide (CPS) of Streptococcus pneumoniae is the main virulence factors required for effective colonization and invasive disease. The capacity to regulate CPS production at the transcriptional level is critical for the survival of S. pneumoniae in different host niches, but little is known about the transcription regulators of cps locus. In the present study, we isolated and identified the response regulator ComE, the master competence switch in transformation of S. pneumoniae, as a transcriptional regulator of cps locus by DNA affinity chromatography-pulldown, MALDI-TOF mass spectrometry (MS) and electrophoretic mobility shift assay (EMSA). Our results showed that phosphorylated mimetic of ComE (ComED58E) bound specifically to the cps locus prompter in vitro, and phosphorylated ComE negatively impacted both cps locus transcription and CPS production attenuating the pneumococcal virulence in vivo. Compared with D39-WT strain, D39ΔcomE mutant exhibited much thicker capsule, attenuated nasopharyngeal colonization and enhanced virulence in both pneumonia and bacteremia models of Balb/c mice. Furthermore, it was demonstrated that CSP-ComD/E competence system involved in regulating negatively the CPS production during the progress of transformation in D39. Our CSP1 induction experiment results showed that the expression of ComE in D39-WT strain increased powerfully by 120% after 10 min of CSP1 induction, but the CPS production in D39-WT strain decreased sharply by 67.1% after 15 min of CSP1 induction. However, the CPS production in D39ΔcomE mutant was almost constant during the whole stage of induction. Additionally, we found that extracellular glucose concentration could affect both the expression of ComE and CPS production of D39 in vitro. Taken together, for the first time, we report that ComE, as a transcriptional regulator of cps locus, plays an important role in transcriptional regulation of cps locus and capsular production level. PMID

  13. Structure-function relationships of immunostimulatory polysaccharides: A review.

    PubMed

    Ferreira, Sónia S; Passos, Cláudia P; Madureira, Pedro; Vilanova, Manuel; Coimbra, Manuel A

    2015-11-05

    Immunostimulatory polysaccharides are compounds capable of interacting with the immune system and enhance specific mechanisms of the host response. Glucans, mannans, pectic polysaccharides, arabinogalactans, fucoidans, galactans, hyaluronans, fructans, and xylans are polysaccharides with reported immunostimulatory activity. The structural features that have been related with such activity are the monosaccharide and glycosidic-linkage composition, conformation, molecular weight, functional groups, and branching characteristics. However, the establishment of structure-function relationships is possible only if purified and characterized polysaccharides are used and selective structural modifications performed. Aiming at contributing to the definition of the structure-function relationships necessary to design immunostimulatory polysaccharides with potential for preventive or therapeutical purposes or to be recognized as health-improving ingredients in functional foods, this review introduces basic immunological concepts required to understand the mechanisms that rule the potential claimed immunostimulatory activity of polysaccharides and critically presents a literature survey on the structural features of the polysaccharides and reported immunostimulatory activity.

  14. Rapid Detection of Contagious Caprine Pleuropneumonia Using a Mycoplasma capricolum subsp. capripneumoniae Capsular Polysaccharide-Specific Antigen Detection Latex Agglutination Test

    PubMed Central

    March, J. B.; Gammack, C.; Nicholas, R.

    2000-01-01

    Latex microspheres (diameter, 8 μm) were coated with anti-Mycoplasma capricolum subsp. capripneumoniae polyclonal immunoglobulin G (IgG) antiserum (anti-F38 biotype). The coated microspheres, when used in a latex agglutination test (LAT), detected M. capricolum subsp. capripneumoniae antigen in the serum of goats with contagious caprine pleuropneumoniae (CCPP). Beads also agglutinated strongly in the presence of purified M. capricolum subsp. capripneumoniae capsular polysaccharide (CPS). Preabsorption of CPS-specific antibodies prior to coating of the beads removed agglutinating activity in the presence of M. capricolum subsp. capripneumoniae, strongly suggesting that CPS is the likely soluble antigen recognized by the test. In addition, the specificity of the LAT exactly mirrored that of an M. capricolum subsp. capripneumoniae CPS-specific monoclonal antibody (WM25): of the 8 other mycoplasma species tested, agglutination was observed only with bovine serogroup 7. The LAT detected all 11 strains of M. capricolum subsp. capripneumoniae examined in this study, with a sensitivity level of 2 ng of CPS, or the equivalent of 1.7 × 104 CFU, in a reaction volume of 0.03 ml of serum. With field sera from goats with CCPP, the results of the LAT exhibited a 67% correlation with the results of the currently used complement fixation test (CFT), with the main discrepancy in diagnosis resulting from the increased sensitivity of the LAT compared to that of CFT. This antigen-detection LAT should prove particularly useful in identifying animals in the earliest stages of CCPP and combines sensitivity and low cost with ease of application in the field, without the need for any specialist training or equipment. PMID:11060083

  15. Design and optimization of a chromatographic purification process for Streptococcus pneumoniae serotype 23F capsular polysaccharide by a Design of Experiments approach.

    PubMed

    Ji, Yu; Tian, Yang; Ahnfelt, Mattias; Sui, Lili

    2014-06-27

    Multivalent pneumococcal vaccines were used worldwide to protect human beings from pneumococcal diseases. In order to eliminate the toxic organic solutions used in the traditional vaccine purification process, an alternative chromatographic process for Streptococcus pneumoniae serotype 23F capsular polysaccharide (CPS) was proposed in this study. The strategy of Design of Experiments (DoE) was introduced into the process development to solve the complicated design procedure. An initial process analysis was given to review the whole flowchart, identify the critical factors of chromatography through FMEA and chose the flowthrough mode due to the property of the feed. A resin screening study was then followed to select candidate resins. DoE was utilized to generate a resolution IV fractional factorial design to further compare candidates and narrow down the design space. After Capto Adhere was selected, the Box-Behnken DoE was executed to model the process and characterize all effects of factors on the responses. Finally, Monte Carlo simulation was used to optimize the process, test the chosen optimal conditions and define the control limit. The results of three scale-up runs at set points verified the DoE and simulation predictions. The final results were well in accordance with the EU pharmacopeia requirements: Protein/CPS (w/w) 1.08%; DNA/CPS (w/w) 0.61%; the phosphorus content 3.1%; the nitrogen 0.315% and the Methyl-pentose percentage 47.9%. Other tests of final pure CPS also met the pharmacopeia specifications. This alternative chromatographic purification process for pneumococcal vaccine without toxic organic solvents was successfully developed by the DoE approach and proved scalability, robustness and suitability for large scale manufacturing.

  16. Diversity of Capsular Polysaccharide Gene Clusters in Kpc-Producing Klebsiella pneumoniae Clinical Isolates of Sequence Type 258 Involved in the Italian Epidemic

    PubMed Central

    D’Andrea, Marco Maria; Amisano, Francesco; Giani, Tommaso; Conte, Viola; Ciacci, Nagaia; Ambretti, Simone; Santoriello, Luisa; Rossolini, Gian Maria

    2014-01-01

    Strains of Klebsiella pneumoniae producing KPC-type beta-lactamases (KPC-Kp) are broadly disseminating worldwide and constitute a major healthcare threat given their extensively drug resistant phenotypes and ability to rapidly disseminate in healthcare settings. In this work we report on the characterization of two different capsular polysaccharide (CPS) gene clusters, named cpsBO-4 and cps207-2, from two KPC-Kp clinical strains from Italy belonging in sequence type (ST) 258, which is one of the most successful ST of KPC-Kp spreading worldwide. While cpsBO-4 was different from known 78 K-types according to the recently proposed typing schemes based on the wzi or wzc gene sequences, cps207-2 was classified as K41 by one of these methods. Bioinformatic analysis revealed that they were represented in the genomic sequences of KPC-Kp from strains of ST258 from different countries, and cpsBO-4 was also detected in a KPC-Kp strain of ST442 from Brazil. Investigation of a collection of 46 ST258 and ST512 (a single locus variant of ST258) clinical strains representative of the recent Italian epidemic of KPC-Kp by means of a multiplex PCR typing approach revealed that cpsBO-4 was the most prevalent type, being detected both in ST258 and ST512 strains with a countrywide distribution, while cps207-2 was only detected in ST258 strains with a more restricted distribution. PMID:24823690

  17. USA300 and USA500 Clonal Lineages of Staphylococcus aureus Do Not Produce a Capsular Polysaccharide Due to Conserved Mutations in the cap5 Locus

    PubMed Central

    Li, Xue; Alam, Md Tauqeer; Read, Timothy D.; Sieth, Julia; Cywes-Bentley, Colette; Dobbins, Ginette; David, Michael Z.; Kumar, Neha; Eells, Samantha J.; Miller, Loren G.; Boxrud, David J.; Chambers, Henry F.; Lynfield, Ruth; Lee, Jean C.; Daum, Robert S.

    2015-01-01

    ABSTRACT The surface capsular polysaccharide (CP) is a virulence factor that has been used as an antigen in several successful vaccines against bacterial pathogens. A vaccine has not yet been licensed against Staphylococcus aureus, although two multicomponent vaccines that contain CP antigens are in clinical trials. In this study, we evaluated CP production in USA300 methicillin-resistant S. aureus (MRSA) isolates that have become the predominant community-associated MRSA clones in the United States. We found that all 167 USA300 MRSA and 50 USA300 methicillin-susceptible S. aureus (MSSA) isolates were CP negative (CP−). Moreover, all 16 USA500 isolates, which have been postulated to be the progenitor lineage of USA300, were also CP−. Whole-genome sequence analysis of 146 CP− USA300 MRSA isolates revealed they all carry a cap5 locus with 4 conserved mutations compared with strain Newman. Genetic complementation experiments revealed that three of these mutations (in the cap5 promoter, cap5D nucleotide 994, and cap5E nucleotide 223) ablated CP production in USA300 and that Cap5E75 Asp, located in the coenzyme-binding domain, is essential for capsule production. All but three USA300 MSSA isolates had the same four cap5 mutations found in USA300 MRSA isolates. Most isolates with a USA500 pulsotype carried three of these four USA300-specific mutations, suggesting the fourth mutation occurred in the USA300 lineage. Phylogenetic analysis of the cap loci of our USA300 isolates as well as publicly available genomes from 41 other sequence types revealed that the USA300-specific cap5 mutations arose sequentially in S. aureus in a common ancestor of USA300 and USA500 isolates. PMID:25852165

  18. Diversity of capsular polysaccharide gene clusters in Kpc-producing Klebsiella pneumoniae clinical isolates of sequence type 258 involved in the Italian epidemic.

    PubMed

    D'Andrea, Marco Maria; Amisano, Francesco; Giani, Tommaso; Conte, Viola; Ciacci, Nagaia; Ambretti, Simone; Santoriello, Luisa; Rossolini, Gian Maria

    2014-01-01

    Strains of Klebsiella pneumoniae producing KPC-type beta-lactamases (KPC-Kp) are broadly disseminating worldwide and constitute a major healthcare threat given their extensively drug resistant phenotypes and ability to rapidly disseminate in healthcare settings. In this work we report on the characterization of two different capsular polysaccharide (CPS) gene clusters, named cpsBO-4 and cps207-2, from two KPC-Kp clinical strains from Italy belonging in sequence type (ST) 258, which is one of the most successful ST of KPC-Kp spreading worldwide. While cpsBO-4 was different from known 78 K-types according to the recently proposed typing schemes based on the wzi or wzc gene sequences, cps207-2 was classified as K41 by one of these methods. Bioinformatic analysis revealed that they were represented in the genomic sequences of KPC-Kp from strains of ST258 from different countries, and cpsBO-4 was also detected in a KPC-Kp strain of ST442 from Brazil. Investigation of a collection of 46 ST258 and ST512 (a single locus variant of ST258) clinical strains representative of the recent Italian epidemic of KPC-Kp by means of a multiplex PCR typing approach revealed that cpsBO-4 was the most prevalent type, being detected both in ST258 and ST512 strains with a countrywide distribution, while cps207-2 was only detected in ST258 strains with a more restricted distribution.

  19. Preparation and characterization of a Staphylococcus aureus capsular polysaccharide-protein conjugate prepared by a low cost technique: a proof-of-concept study.

    PubMed

    Pujato, Nazarena; Díaz, Germán; Barbagelata, María Sol; Vicco, Miguel Hernán; Calvinho, Luis Fernando; Marcipar, Iván Sergio

    2015-01-01

    Staphylococcus aureus is a worldwide distributed pathogen that produces several diseases in many species and is the major cause of mastitis in dairy cows. S. aureus capsular polysaccharide 5 (CP5) has been widely proposed as a vaccine candidate since it is expressed in a high proportion of isolates from intramammary infections and is able to induce opsonophagocytic antibodies. However, to reach immunological properties, polysaccharides need to be coupled to carrier proteins. The aim of this study was to evaluate a conjugation method employing p-benzoquinone (PBQ), which was not previously reported for the development of vaccine components. Purified S. aureus CP5 was coupled to human serum albumin (HSA) with high efficiency, reaching a rate PS/protein of 0.5. Mice groups were immunized at days 0, 14, 28, and 42, with the conjugate (CP5-HSAPBQ), free CP5, or PBS, formulated with incomplete Freund adjuvant, and after 3 months, they were challenged with free CP5 to evaluate the memory response. IgG and IgM isotypes were measured on serum samples all along the experiment, and IgG subclasses were determined to analyze the humoral profile. In contrast to the response obtained with free CP5, CP5-HSAPBQ induced IgG titers of 1/238,900 after three doses and a memory response was observed after the challenge. Results indicate that immunization with CP5-HSAPBQ effectively induce a T-dependent immune response against CP5. Moreover, besides IgG2a was the main subtype obtained, the joint production of specific IgG1, IgG2b, and IgG3 types indicated a balanced humoral response. As p-benzoquinone conjugation of CPs to proteins is far less expensive and straightforward than other methods commonly used in vaccine preparations, the robust humoral response obtained using this method points out that this can be an interesting alternative to prepare S. aureus CP5 conjugate vaccines.

  20. STEPWISE INTRATYPE TRANSFORMATION OF PNEUMOCOCCUS FROM R TO S BY WAY OF A VARIANT INTERMEDIATE IN CAPSULAR POLYSACCHARIDE PRODUCTION

    PubMed Central

    MacLeod, Colin M.; Krauss, Marjorie R.

    1947-01-01

    1. A variant intermediate between the classical R and S forms has been isolated by selective procedures from a rough strain of pneumococcus originally derived from Type II S. 2. The intermediate variant D39/Int53 is avirulent for mice, forms rough colonies, and does not possess a demonstrable capsule. However, it synthesizes SSSII which is immunologically indistinguishable from that produced by fully encapsulated pneumococcus Type II, though in much smaller amount. The polysaccharide is present as a surface component and as it exists in the cell is highly antigenic for rabbits. 3. An extract of the intermediate variant causes the transformation in vitro of an R strain into a variant resembling the intermediate in SSSII production but without any apparent alteration in the colonial characteristics of the R variant. 4. The intermediate variant is convertible in vivo, into a fully encapsulated strain of pneumococcus Type II. Transformation of the intermediate to a heterologous type of pneumococcus (Type III) was unsuccessful. 5. A method is described for the preparation of transforming extracts of pneumococci utilizing the massive growth of the organisms obtained in the presence of a large concentration of glucose. PMID:19871689

  1. Biosynthesis of UDP-GlcA, a key metabolite for capsular polysaccharide synthesis in the pathogenic fungus Cryptococcus neoformans

    PubMed Central

    2004-01-01

    UDP-glucose dehydrogenase catalyses the conversion of UDP-glucose into UDP-GlcA, a critical precursor for glycan synthesis across evolution. We have cloned the gene encoding this important enzyme from the opportunistic pathogen Cryptococcus neoformans. In this fungus, UDP-GlcA is required for the synthesis of capsule polysaccharides, which in turn are essential for virulence. The gene was expressed in Escherichia coli and the 51.3-kDa recombinant protein from wild-type and five mutants was purified for analysis. The cryptococcal enzyme is strongly inhibited by UDP-xylose and NADH, has highest activity at pH 7.5 and demonstrates Km (app) values of 0.1 and 1.5 mM for NAD+ and UDP-glucose respectively. Its activity was significantly decreased by mutations in the putative sites of NAD+ and UDP-glucose binding. Unlike previously reported eukaryotic UDP-glucose dehydrogenases, which are hexamers, the cryptococcal enzyme is a dimer. PMID:15030319

  2. The K1 Capsular Polysaccharide of Acinetobacter baumannii Strain 307-0294 Is a Major Virulence Factor ▿

    PubMed Central

    Russo, Thomas A.; Luke, Nicole R.; Beanan, Janet M.; Olson, Ruth; Sauberan, Shauna L.; MacDonald, Ulrike; Schultz, L. Wayne; Umland, Timothy C.; Campagnari, Anthony A.

    2010-01-01

    Acinetobacter baumannii is a pathogen of increasing medical importance with a propensity to be multidrug resistant, thereby making treatment challenging. Little is known of virulence traits in A. baumannii. To identify virulence factors and potential drug targets, random transposon (Tn) mutants derived from the A. baumannii strain AB307-0294 were screened to identify genes essential for growth in human ascites fluid in vitro, an inflammatory exudative fluid. These studies led to the identification of two genes that were predicted to be required for capsule polymerization and assembly. The first, ptk, encodes a putative protein tyrosine kinase (PTK), and the second, epsA, encodes a putative polysaccharide export outer membrane protein (EpsA). Monoclonal antibodies used in flow cytometric and Western analyses confirmed that these genes are required for a capsule-positive phenotype. A capsule-positive phenotype significantly optimized growth in human ascites fluid, survival in human serum, and survival in a rat soft tissue infection model. Importantly, the clearance of the capsule-minus mutants AB307.30 (ptk mutant, capsule minus) and AB307.45 (epsA mutant, capsule minus) was complete and durable. These data demonstrated that the K1 capsule from AB307-0294 was an important protectin. Further, these data suggested that conserved proteins, which contribute to the capsule-positive phenotype, are potential antivirulence drug targets. Therefore, the results from this study have important biologic and translational implications and, to the best of our knowledge, are the first to address the role of capsule in the pathogenesis of A. baumannii infection. PMID:20643860

  3. Constitutive Expression of the Vi Polysaccharide Capsular Antigen in Attenuated Salmonella enterica Serovar Typhi Oral Vaccine Strain CVD 909

    PubMed Central

    Wang, Jin Yuan; Noriega, Fernando R.; Galen, James E.; Barry, Eileen; Levine, Myron M.

    2000-01-01

    Live oral Ty21a and parenteral Vi polysaccharide vaccines provide significant protection against typhoid fever, albeit by distinct immune mechanisms. Vi stimulates serum immunoglobulin G Vi antibodies, whereas Ty21a, which does not express Vi, elicits humoral and cell-mediated immune responses other than Vi antibodies. Protection may be enhanced if serum Vi antibody as well as cell-mediated and humoral responses can be stimulated. Disappointingly, several new attenuated Salmonella enterica serovar Typhi oral vaccines (e.g., CVD 908-htrA and Ty800) that elicit serum O and H antibody and cell-mediated responses following a single dose do not stimulate serum Vi antibody. Vi expression is regulated in response to environmental signals such as osmolarity by controlling the transcription of tviA in the viaB locus. To investigate if Vi antibodies can be stimulated if Vi expression is rendered constitutive, we replaced PtviA in serovar Typhi vaccine CVD 908-htrA with the constitutive promoter Ptac, resulting in CVD 909. CVD 909 expresses Vi even under high-osmolarity conditions and is less invasive for Henle 407 cells. In mice immunized with a single intranasal dose, CVD 909 was more immunogenic than CVD 908-htrA in eliciting serum Vi antibodies (geometric mean titer of 160 versus 49, P = 0.0007), whereas O antibody responses were virtually identical (geometric mean titer of 87 versus 80). In mice challenged intraperitoneally with wild-type serovar Typhi 4 weeks after a single intranasal immunization, the mortality of those immunized with CVD 909 (3 of 8) was significantly lower than that of control mice (10 of 10, P = 0.043) or mice given CVD 908-htrA (9 of 10, P = 0.0065). PMID:10899868

  4. The capsular network of Klebsiella pneumoniae.

    PubMed

    Cassone, A; Garaci, E

    1977-06-01

    Attempts at improving chemical fixation for electron-microscopic observation of the capsule of Klebsiella pneumoniae were made. The capsule was preserved by using alcian blue - lanthanum and tris-(1-aziridinyl) phosphine oxide (TAPO) - aldehyde - osmium procedures. Despite the different retention of the overall capsular material and minor variations in morphological details, in both cases the interpretation of ultrastructural patterns suggested that the capsule be composed of a meshed network of thin polysaccharide fibrils radiating from the cell wall. This organization is in keeping with all recognized chemical properties of bacterial polysaccharide capsules or, at least, does not contradict them. Moreover, an effective preservation of bacterial structures other than capsule has been obtained, mostly in specimens fixed by the TAPO-aldehyde-osmium method, a fact which gives further reliability to the technical approach used for capsule visualization.

  5. Polysaccharide structure of tetrasporic red seaweed Tichocarpus crinitus.

    PubMed

    Byankina Barabanova, A O; Sokolova, E V; Anastyuk, S D; Isakov, V V; Glazunov, V P; Volod'ko, A V; Yakovleva, I M; Solov'eva, T F; Yermak, I M

    2013-10-15

    Sulfated polysaccharide isolated from tetrasporic plants of Tichocarpus crinitus was investigated. The polysaccharide was isolated by two methods: with water extraction at 80 °C (HT) and with a mild alkaline extraction (AE). The extracted polysaccharides were presented by non-gelling ones only, while galactose and 3,6-AG were the main monosaccharides, at the same time amount of 3,6-AG in AE polysaccharides was the similar to that of HT. According to methods of spectroscopy and mass spectrometry, the polysaccharide from tetrasporic T. crinitus contains main blocks of 1,3-linked β-D-galactopyranosyl-2,4-disulfates and 1,4-linked 3,6-anhydro-α-D-galactopyranosyl while 6-sulfated 4-linked galactopyranosyl resudies are randomly distributed along the polysaccharide chain. The alkaline treatment of HT polysaccharide results in obtaining polysaccharide with regular structure that composed of alternating 1,3-linked β-D-galactopyranosyl-2,4-disulfates and 1,4-linked 3,6-anhydro-α-D-galactopyranosyl residues. Native polysaccharide (HT) possessed both high anticoagulant and antiplatelet activity measured by fibrin clotting and platelet aggregation induced by collagen. This activity could be connected with peculiar chemical structure of HT polysaccharide which has high sulfation degree and contains also 3,6-anhydrogalactose in the polymer chain.

  6. Structural diversity of lytic polysaccharide monooxygenases.

    PubMed

    Vaaje-Kolstad, Gustav; Forsberg, Zarah; Loose, Jennifer Sm; Bissaro, Bastien; Eijsink, Vincent Gh

    2017-01-10

    Lytic polysaccharide monooxygenases (LPMOs) catalyze the oxidative cleavage of glycosidic bonds and represent a promising resource for development of industrial enzyme cocktails for biomass processing. LPMOs show high sequence and modular diversity and are known, so far, to cleave insoluble substrates such as cellulose, chitin and starch, as well as hemicelluloses such as beta-glucan, xyloglucan and xylan. All LPMOs share a catalytic histidine brace motif to bind copper, but differ strongly when it comes to the nature and arrangement of residues on the substrate-binding surface. In recent years, the number of available LPMO structures has increased rapidly, including the first structure of an enzyme-substrate complex. The insights gained from these structures is reviewed below.

  7. Structural modification of polysaccharides: A biochemical-genetic approach

    NASA Technical Reports Server (NTRS)

    Kern, Roger G.; Petersen, Gene R.

    1991-01-01

    Polysaccharides have a wide range of industrial and biomedical applications. An industry trend is underway towards the increased use of bacteria to produce polysaccharides. Long term goals of this work are the adaptation and enhancement of saccharide properties for electronic and optic applications. In this report we illustrate the application of enzyme-bearing bacteriophage on strains of the enteric bacterium Klebsiella pneumoniae, which produces a polysaccharide with the relatively rare rheological property of drag-reduction. This has resulted in the production of new polysaccharides with enhanced rheological properties. Our laboratory is developing techniques for processing and structurally modifying bacterial polysaccharides and oligosaccharides which comprise their basic polymeric repeat units. Our research has focused on bacteriophage which produce specific polysaccharide degrading enzymes. This has lead to the development of enzymes generated by bacteriophage as tools for polysaccharide modification and purification. These enzymes were used to efficiently convert the native material to uniform-sized high molecular weight polymers, or alternatively into high-purity oligosaccharides. Enzyme-bearing bacteriophage also serve as genetic selection tools for bacteria that produce new families of polysaccharides with modified structures.

  8. Differential Regulation of IgG Anti-Capsular Polysaccharide and Antiprotein Responses to Intact Streptococcus pneumoniae in the Presence of Cognate CD4+ T Cell Help

    DTIC Science & Technology

    2004-01-01

    polysaccharide (PPS14), the phosphorylcholine determinant of the cell wall C-polysaccharide, and the cell wall protein, pneumococcal surface protein A...a more rapid delivery of CD4 T cell help. In contrast, the IgG anti- phosphorylcholine response, although also dependent on CD4 T cells, is TCR...and/or IgG isotypes specific for the phosphorylcholine (PC) determinant of the cell wall C-polysaccharide (teichoic acid) and for the cell wall

  9. Chemical Structures and Bioactivities of Sulfated Polysaccharides from Marine Algae

    PubMed Central

    Jiao, Guangling; Yu, Guangli; Zhang, Junzeng; Ewart, H. Stephen

    2011-01-01

    Sulfated polysaccharides and their lower molecular weight oligosaccharide derivatives from marine macroalgae have been shown to possess a variety of biological activities. The present paper will review the recent progress in research on the structural chemistry and the bioactivities of these marine algal biomaterials. In particular, it will provide an update on the structural chemistry of the major sulfated polysaccharides synthesized by seaweeds including the galactans (e.g., agarans and carrageenans), ulvans, and fucans. It will then review the recent findings on the anticoagulant/antithrombotic, antiviral, immuno-inflammatory, antilipidemic and antioxidant activities of sulfated polysaccharides and their potential for therapeutic application. PMID:21566795

  10. Synthetic trimer and tetramer of 3-beta-D-ribose-(1-1)-D-ribitol-5-phosphate conjugated to protein induce antibody responses to Haemophilus influenzae type b capsular polysaccharide in mice and monkeys.

    PubMed Central

    Peeters, C C; Evenberg, D; Hoogerhout, P; Käyhty, H; Saarinen, L; van Boeckel, C A; van der Marel, G A; van Boom, J H; Poolman, J T

    1992-01-01

    Synthetic oligosaccharides derived from the capsular polysaccharide (PRP) of Haemophilus influenzae type b were conjugated to carrier proteins via a thioether linkage. Conjugates were made of trimeric and tetrameric ribose-ribitol-phosphate and tetanus toxoid or diphtheria toxin. All conjugates elicited anti-PRP antibody responses with an increasing immunoglobulin G/immunoglobulin M ratio in adult mice and monkeys. Trimer conjugates elicited lower anti-PRP antibody responses compared with tetramer conjugates. Adult monkeys responded equally well to the tetrameric oligosaccharide-tetanus toxoid conjugate as to the oligosaccharide-CRM197 conjugate (HbOC), which elicits protective levels of serum antibodies in human infants after two or three injections. PMID:1563770

  11. Structural and functional comparison of polysaccharide-degrading enzymes.

    PubMed

    Jedrzejas, M J

    2000-01-01

    Sugar molecules as well as enzymes degrading them are ubiquitously present in physiological systems, especially for vertebrates. Polysaccharides have at least two aspects to their function, one due to their mechanical properties and the second one involves multiple regulatory processes or interactions between molecules, cells, or extracellular space. Various bacteria exert exogenous pressures on their host organism to diversity glycans and their structures in order for the host organism to evade the destructive function of such microbes. Many bacterial organism produce glycan-degrading enzymes in order to facilitate their invasion of host tissues. Such polysaccharide degrading enzymes utilize mainly two modes of polysaccharide-degradation, a hydrolysis and a beta-elimination process. The three-dimensional structures of several of these enzymes have been elucidated recently using X-ray crystallography. There are many common structural motifs among these enzymes, mainly the presence of an elongated cleft transversing these molecules which functions as a polysaccharide substrate binding site as well as the catalytic site for these enzymes. The detailed structural information obtained about these enzymes allowed formulation of proposed mechanisms of their action. The polysaccharide lyases utilize a proton acceptance and donation mechanism (PAD), whereas polysaccharide hydrolases use a direct double displacement (DD) mechanism to degrade their substrates.

  12. Correlation Between Chain Architecture and Hydration Water Structure in Polysaccharides

    NASA Astrophysics Data System (ADS)

    Grossutti, Michael; Dutcher, John

    The physical properties of confined water can differ dramatically from those of bulk water. Hydration water associated with polysaccharides provides a particularly important example of confined water, with differences in polysaccharide structure providing different spatially confined environments for water adsorption. We have used attenuated total reflection infrared (ATR-IR) spectroscopy to investigate the structure of hydration water in films of three different polysaccharides under controlled relative humidity (RH) conditions. We compare the results obtained for films of highly branched, monodisperse phytoglycogen nanoparticles to those obtained for two unbranched polysaccharides, hyaluronic acid (HA) and chitosan. We find similarities between water structuring in the two linear polysaccharides, and significant differences for phytoglycogen. In particular, the phytoglycogen nanoparticles exhibited high network water connectivity, and a large increase in the fraction of multimer water clusters with increasing RH, whereas the water structure for HA and chitosan was found to be insensitive to changes in RH. These measurements provide unique insight into the relationship between the chain architecture and hydration of polysaccharides.

  13. Anticorrosive Microbial Polysaccharides: Structure-Function Relationships

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water-soluble microbial polysaccharides are often implicated in biofilm formation and are believed to mediate cell-cell aggregation and adhesion to surfaces. Generally, biofilm formation is considered harmful or undesirable, as it leads to increased drag, plugging of pores, dimished heat transfer, ...

  14. Molecular analysis of region 1 of the Escherichia coli K5 antigen gene cluster: a region encoding proteins involved in cell surface expression of capsular polysaccharide.

    PubMed Central

    Pazzani, C; Rosenow, C; Boulnois, G J; Bronner, D; Jann, K; Roberts, I S

    1993-01-01

    The nucleotide sequence of region 1 of the K5 antigen gene cluster of Escherichia coli was determined. This region is postulated to encode functions which, at least in part, participate in translocation of polysaccharide across the periplasmic space and onto the cell surface. Analysis of the nucleotide sequence revealed five genes that encode proteins with predicted molecular masses of 75.7, 60.5, 44, 43, and 27 kDa. The 27-kDa protein was 70.7% homologous to the CMP-2-keto-3-deoxyoctulosonic acid synthetase enzyme encoded by the E. coli kdsB gene, indicating the presence of a structural gene for a similar enzyme within the region 1 operon. The 43-kDa protein was homologous to both the Ctrb and BexC proteins encoded by the Neisseria meningitidis and Haemophilus influenzae capsule gene clusters, respectively, indicating common stages in the expression of capsules in these gram-negative bacteria. However, no homology was detected between the 75.7, 60.5-, and 44-kDa proteins and any of the proteins so far described for the H. influenzae and N. meningitidis capsule gene clusters. Images PMID:8397187

  15. Structural characterization of polysaccharides from bamboo

    NASA Astrophysics Data System (ADS)

    Kamil, Ruzaimah Nik Mohamad; Yusuf, Nur'aini Raman; Yunus, Normawati M.; Yusup, Suzana

    2014-10-01

    The alkaline and water soluble polysaccharides were isolate by sequential extractions with distilled water, 60% ethanol containing 1%, 5% and 8% NaOH. The samples were prepared at 60 °C for 3 h from local bamboo. The functional group of the sample were examined using FTIR analysis. The most precipitate obtained is from using 60% ethanol containing 8% NaOH with yield of 2.6%. The former 3 residues isolated by sequential extractions with distilled water, 60% ethanol containing 1% and 5% NaOH are barely visible after filtering with cellulose filter paper. The FTIR result showed that the water-soluble polysaccharides consisted mainly of OH group, CH group, CO indicates the carbohydrate and sugar chain. The sample weight loss was slightly decreased with increasing of temperature.

  16. Polysaccharide-Based Vaccines

    NASA Astrophysics Data System (ADS)

    Santana, Violeta Fernández; Balbin, Yury Valdés; Calderón, Janoi Chang; Icart, Luis Peña; Verez-Bencomo, Vicente

    Capsular polysaccharides (CPS) and lipopolysaccharides from bacteria are employed for the production of vaccines against human diseases. Initial development of CPS as a vaccine was followed by the development and introduction of conjugate polysaccharide-protein vaccines. The principles leading to both developments are reviewed.

  17. Structural characteristics of a bioactive polysaccharide from Sorghum arundinaceum.

    PubMed

    da Silva, Bernadete P; Silva, Graziela M; Mendes, Tatiana P; Parente, José P

    2003-01-01

    A polysaccharide, an alpha-D-glucan with an apparent molecular weight of 6.85 x 10(4), called PSa glucan, was isolated from fresh seeds of Sorghum arundinaceum by fractionation on Sephacryl S-300 HR and Sephadex G-25. Chemical and spectroscopic studies indicated that it has a highly branched glucan type structure composed of alpha-(1-->4) linked D-glucopyranose residues with (1-->3), (1-->6) branching points, and a significant amount of alpha-(1-->6) branching to alpha-(1-->3) linked D-glucopyranose residues. The anti-inflammatory activity of the polysaccharide was performed using the capillary permeability assay.

  18. Composition and Partial Structure Characterization of Tremella Polysaccharides

    PubMed Central

    2009-01-01

    Heteropolysaccharides isolated from liquid cultures of nine Tremella species contained 0.3 to 1.2% protein, 2.7 to 5% ash, 0.9 to 3.4% acetyl groups, 76.5 to 84.2% carbohydrates and trace amounts of starch. The polysaccharides in aqueous solution were slightly acidic (pH 5.1 to 5.6). They consisted of the following monomeric sugars: fucose, ribose, xylose, arabinose, mannose, galactose, glucose and glucuronic acid. The backbones of the polysaccharide structures consisted of α-(1→3)-links while the side chains were β-linked. PMID:23983549

  19. Structure of pectic polysaccharides from sunflower salts-soluble fraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The manuscript discusses the structural features of pectin polysaccharides extracted from seedless sunflower head residues. The analysis using 1H, 13C and two-dimensional gHSQC NMR showed various numbers of methyl and hydroxyl groups attached to the anomeric carbons in the pectin backbone at differe...

  20. Biosynthesis of dermatan sulphate. Defructosylated Escherichia coli K4 capsular polysaccharide as a substrate for the D-glucuronyl C-5 epimerase, and an indication of a two-base reaction mechanism.

    PubMed Central

    Hannesson, H H; Hagner-McWhirter, A; Tiedemann, K; Lindahl, U; Malmström, A

    1996-01-01

    The capsular polysaccharide from Escherichia coli K4 consists of a chondroitin ([GlcA(beta 1-->3)GalNAc(beta 1-->4)]n) backbone, to which beta-fructofuranose units are linked to C-3 of D-glucuronic acid (GlcA) residues. Removal of the fructose units by mild acid hydrolysis provided a substrate for the GlcA C-5 epimerase, which is involved in the generation of L-iduronic acid (IdoA) units during dermatan sulphate biosynthesis. Incubation of this substrate with solubilized fibroblast microsomal enzyme in the presence of 3H2O resulted in the incorporation of tritium at C-5 of hexuronyl units. A Km of 67 x 10(-6) M hexuronic acid (equivalent to disaccharide units) was determined, which is similar to that (80 x 10(-6) M) obtained for dermatan (desulphated dermatan sulphate). Vmax was about 4 times higher with dermatan than with the K4 substrate. A defructosylated K4 polysaccharide isolated after incubation of bacteria with D-[5-3H]glucose released 3H2O on reaction with the epimerase, and thus could be used to assay the enzyme. Incubation of a K4 substrate with solubilized microsomal epimerase for 6 h in the presence of 3H2O resulted in the formation of about 5% IdoA and approximately equal amounts of 3H in GlcA and IdoA. A corresponding incubation of dermatan yielded approx. 22% GlcA, which contained virtually all the 3H label. These results are tentatively explained in terms of a two-base reaction mechanism, involving a monoprotic L-ido-specific base and a polyprotic D-gluco-specific base. Most of the IdoA residues generated by the enzyme occurred singly, although some formation of two or three consecutive IdoA-containing disaccharide units was observed. PMID:8573097

  1. Nasal immunization of mice with AFCo1 or AFPL1 plus capsular polysaccharide Vi from Salmonella typhi induces cellular response and memory B and T cell responses.

    PubMed

    Romeu, Belkis; Lastre, Miriam; Reyes, Laura; González, Elizabeth; Borrero, Yusnaby; Lescaille, Diandra; Pérez, Rocmira; Nuñez, Darzy; Pérez, Oliver

    2014-12-05

    The response to infection against Salmonella involves both B and T cell mediated immunity. An effective immunization can activate an adequate immune response capable to control the primary infection and protect against a secondary infection. Mucosal vaccination, by inducing local pathogen-specific immune responses, has the potential to counter mucosally transmitted pathogens at the portal of entry, thereby increasing the efficacy of vaccines. The aim of this work was to explore the efficacy of AFCo1 or AFPL1, as mucosal adjuvants to stimulate cell immunity and memory responses against Vi polysaccharide antigen of Salmonella typhi (PsVi). Mice immunized with 3 intranasal doses exhibited high levels of PsVi-specific IgG (p<0.05), IgG2a and IgG2c subclasses. Also, an amplified recall response after a booster immunization with a plain polysaccharide vaccine was induced. Avidities index were higher in mice immunized with adjuvanted formulations at different chaotropic concentrations. Furthermore, IL-12 and IFN-γ levels in nasally vaccinated mice with both adjuvants were induced. Moreover, priming with 3 doses followed by booster immunization with VaxTyVi(®) resulted in high levels of anti-Vi specific IgG, IgG subclasses and antibody avidity. Long lived plasma cells in bone marrow, memory B cells and long-term memory T cells after booster dose were induced. The combined formulation of Vi polysaccharide with mucosal adjuvants provides an improved immunogenicity, in particular with regard to cellular responses and long lasting cells responses.

  2. Functional and Structural Characterization of Polysaccharide Co-polymerase Proteins Required for Polymer Export in ATP-binding Cassette Transporter-dependent Capsule Biosynthesis Pathways*

    PubMed Central

    Larue, Kane; Ford, Robert C.; Willis, Lisa M.; Whitfield, Chris

    2011-01-01

    Neisseria meningitidis serogroup B and Escherichia coli K1 bacteria produce a capsular polysaccharide (CPS) that is composed of α2,8-linked polysialic acid (PSA). Biosynthesis of PSA in these bacteria occurs via an ABC (ATP-binding cassette) transporter-dependent pathway. In N. meningitidis, export of PSA to the surface of the bacterium requires two proteins that form an ABC transporter (CtrC and CtrD) and two additional proteins, CtrA and CtrB, that are proposed to form a cell envelope-spanning export complex. CtrA is a member of the outer membrane polysaccharide export (OPX) family of proteins, which are proposed to form a pore to mediate export of CPSs across the outer membrane. CtrB is an inner membrane protein belonging to the polysaccharide co-polymerase (PCP) family. PCP proteins involved in other bacterial polysaccharide assembly systems form structures that extend into the periplasm from the inner membrane. There is currently no structural information available for PCP or OPX proteins involved in an ABC transporter-dependent CPS biosynthesis pathway to support their proposed roles in polysaccharide export. Here, we report cryo-EM images of purified CtrB reconstituted into lipid bilayers. These images contained molecular top and side views of CtrB and showed that it formed a conical oligomer that extended ∼125 Å from the membrane. This structure is consistent with CtrB functioning as a component of an envelope-spanning complex. Cross-complementation of CtrA and CtrB in E. coli mutants with defects in genes encoding the corresponding PCP and OPX proteins show that PCP-OPX pairs require interactions with their cognate partners to export polysaccharide. These experiments add further support for the model of an ABC transporter-PCP-OPX multiprotein complex that functions to export CPS across the cell envelope. PMID:21454677

  3. Antibacterial Activity of Cold Atmospheric Pressure Argon Plasma against 78 Genetically Different (mecA, luk-P, agr or Capsular Polysaccharide Type) Staphylococcus aureus Strains.

    PubMed

    Matthes, Rutger; Lührman, Anne; Holtfreter, Silva; Kolata, Julia; Radke, Dörte; Hübner, Nils-Olaf; Assadian, Ojan; Kramer, Axel

    2016-01-01

    Previous studies on the antimicrobial activity of cold atmospheric pressure argon plasma showed varying effects against mecA+ or mecA-Staphylococcus aureus strains. This observation may have important clinical and epidemiological implications. Here, the antibacterial activity of argon plasma was investigated against 78 genetically different S. aureus strains, stratified by mecA, luk-P, agr1-4, or the cell wall capsule polysaccharide types 5 and 8. kINPen09® served as the plasma source for all experiments. On agar plates, mecA+luk-P-S. aureus strains showed a decreased susceptibility against plasma compared to other S. aureus strains. This study underlines the high complexity of microbial defence against antimicrobial treatment and confirms a previously reported strain-dependent susceptibility of S. aureus to plasma treatment.

  4. Lytic polysaccharide monooxygenases disrupt the cellulose fibers structure

    PubMed Central

    Villares, Ana; Moreau, Céline; Bennati-Granier, Chloé; Garajova, Sona; Foucat, Loïc; Falourd, Xavier; Saake, Bodo; Berrin, Jean-Guy; Cathala, Bernard

    2017-01-01

    Lytic polysaccharide monooxygenases (LPMOs) are a class of powerful oxidative enzymes that breakdown recalcitrant polysaccharides such as cellulose. Here we investigate the action of LPMOs on cellulose fibers. After enzymatic treatment and dispersion, LPMO-treated fibers show intense fibrillation. Cellulose structure modifications visualized at different scales indicate that LPMO creates nicking points that trigger the disintegration of the cellulose fibrillar structure with rupture of chains and release of elementary nanofibrils. Investigation of LPMO action using solid-state NMR provides direct evidence of modification of accessible and inaccessible surfaces surrounding the crystalline core of the fibrils. The chains breakage likely induces modifications of the cellulose network and weakens fibers cohesion promoting their disruption. Besides the formation of new initiation sites for conventional cellulases, this work provides the first evidence of the direct oxidative action of LPMOs with the mechanical weakening of the cellulose ultrastructure. LPMOs can be viewed as promising biocatalysts for enzymatic modification or degradation of cellulose fibers. PMID:28071716

  5. Lytic polysaccharide monooxygenases disrupt the cellulose fibers structure.

    PubMed

    Villares, Ana; Moreau, Céline; Bennati-Granier, Chloé; Garajova, Sona; Foucat, Loïc; Falourd, Xavier; Saake, Bodo; Berrin, Jean-Guy; Cathala, Bernard

    2017-01-10

    Lytic polysaccharide monooxygenases (LPMOs) are a class of powerful oxidative enzymes that breakdown recalcitrant polysaccharides such as cellulose. Here we investigate the action of LPMOs on cellulose fibers. After enzymatic treatment and dispersion, LPMO-treated fibers show intense fibrillation. Cellulose structure modifications visualized at different scales indicate that LPMO creates nicking points that trigger the disintegration of the cellulose fibrillar structure with rupture of chains and release of elementary nanofibrils. Investigation of LPMO action using solid-state NMR provides direct evidence of modification of accessible and inaccessible surfaces surrounding the crystalline core of the fibrils. The chains breakage likely induces modifications of the cellulose network and weakens fibers cohesion promoting their disruption. Besides the formation of new initiation sites for conventional cellulases, this work provides the first evidence of the direct oxidative action of LPMOs with the mechanical weakening of the cellulose ultrastructure. LPMOs can be viewed as promising biocatalysts for enzymatic modification or degradation of cellulose fibers.

  6. Structural elucidation of polysaccharide fractions from brown seaweed Sargassum pallidum.

    PubMed

    Ye, Hong; Zhou, Chunhong; Li, Wei; Hu, Bing; Wang, Xiaoqing; Zeng, Xiaoxiong

    2013-09-12

    The structural characteristics of two purified fractions of polysaccharides from Sargassum pallidum (SPS) were investigated in the present study. As results, the molecular weights of the two polysaccharide fractions, SPS-3-1 and SPS-3-2, were determined to be 5.87 and 7.25 kDa, respectively. SPS-3-1 was composed of glucose, mannose and galactose in a molar ratio of 11.18:1.00:0.96, while SPS-3-2 was composed of fucose, xylose, mannose, glucose and galactose in a molar ratio of 2.53:0.61:1.00:0.46:0.92. Both SPS-3-1 and SPS-3-2 exhibited the characteristics of polysaccharide in the frequency range of 4000-400 cm(-1) based on their Fourier-transform infrared spectra. Furthermore, the results of periodic acid oxidation, Smith degradation, methylation analysis and nuclear magnetic resonance spectroscopic analysis suggested that SPS-3-2 was composed of (1→4)-linked fucopyranosyl backbone and (1→3)-linked galactopyranosyl, (1→3)-linked mannopyranosyl, (1→2)-linked xylopyranosyl and (1→6)-linked glucopyranosyl branch chains.

  7. Direct visualization by cryo-EM of the mycobacterial capsular layer: a labile structure containing ESX-1-secreted proteins.

    PubMed

    Sani, Musa; Houben, Edith N G; Geurtsen, Jeroen; Pierson, Jason; de Punder, Karin; van Zon, Maaike; Wever, Brigitte; Piersma, Sander R; Jiménez, Connie R; Daffé, Mamadou; Appelmelk, Ben J; Bitter, Wilbert; van der Wel, Nicole; Peters, Peter J

    2010-03-05

    The cell envelope of mycobacteria, a group of Gram positive bacteria, is composed of a plasma membrane and a Gram-negative-like outer membrane containing mycolic acids. In addition, the surface of the mycobacteria is coated with an ill-characterized layer of extractable, non-covalently linked glycans, lipids and proteins, collectively known as the capsule, whose occurrence is a matter of debate. By using plunge freezing cryo-electron microscopy technique, we were able to show that pathogenic mycobacteria produce a thick capsule, only present when the cells were grown under unperturbed conditions and easily removed by mild detergents. This detergent-labile capsule layer contains arabinomannan, alpha-glucan and oligomannosyl-capped glycolipids. Further immunogenic and proteomic analyses revealed that Mycobacterium marinum capsule contains high amounts of proteins that are secreted via the ESX-1 pathway. Finally, cell infection experiments demonstrated the importance of the capsule for binding to cells and dampening of pro-inflammatory cytokine response. Together, these results show a direct visualization of the mycobacterial capsular layer as a labile structure that contains ESX-1-secreted proteins.

  8. The structure of mushroom polysaccharides and their beneficial role in health.

    PubMed

    Huang, Xiaojun; Nie, Shaoping

    2015-10-01

    Mushroom is a kind of fungus that has been popular for its special flavour and renowned biological values. The polysaccharide contained in mushroom is regarded as one of the primary bioactive constituents and is beneficial for health. The structural features and bioactivities of mushroom polysaccharides have been studied extensively. It is believed that the diverse biological bioactivities of polysaccharides are closely related to their structure or conformation properties. In this review, the structural characteristics, conformational features and bioactivities of several mushroom polysaccharides are summarized, and their beneficial mechanisms and the relationships between their structure and bioactivities are also discussed.

  9. EXTRACELLULAR POLYSACCHARIDES OF AZOTOBACTER VINELANDII1

    PubMed Central

    Cohen, Gary H.; Johnstone, Donald B.

    1964-01-01

    Cohen, Gary H. (University of Vermont, Burlington), and Donald B. Johnstone. Extracellular polysaccharides of Azotobacter vinelandii. J. Bacteriol. 88:329–338. 1964.—Extracellular polysaccharides synthetized by Azotobacter vinelandii strains 155, 102, and 3A were shown to be carboxylic acid heteropolysaccharides of apparent high molecular weight. Cells were grown in a nitrogen-free, mineral broth medium with 2% sucrose. Extracellular slime was recovered by centrifugation and purified by repeated alcohol precipitation and Sevag deproteinization. Capsular polysaccharide was recovered from washed cells by mild alkaline digestion. Methods of isolation and purification appeared to provide polysaccharide showing no evidence of heterogeneity when examined by chemical and physical methods. Infrared analysis of purified slime from the three strains suggested fundamental structural similarities. Colorimetric, paper chromatographic, and enzymatic analyses on both intact and acid-hydrolyzed slime polysaccharide indicated that the polymers contained in common galacturonic acid, [α] d-glucose, and rhamnose at a ratio of approximately 43:2:1, as well as a hexuronic acid lactone, probably mannurono-lactone. However, as shown by chemical and infrared analysis, minor differences did exist; namely, slime from strain 155 and 102 contained o-acetyl groups, whereas slime from strain 3A contained none. A sialic acid-like component (1.5% of dry weight of the polysaccharide, calculated as N-acetyl neuraminic acid), was found only in the slime of strain 155. Capsular polysaccharide composition closely resembled that for slime. It is of interest that the major slime components were identical whether the energy source provided for the cells was sucrose, glucose, fructose, or ethanol. PMID:14203348

  10. The Effect of a BSA Conjugate of a Synthetic Hexasaccharide Related to the Fragment of Capsular Polysaccharide of Streptococcus pneumoniae Type 14 on the Activation of Innate and Adaptive Immune Responses

    PubMed Central

    Akhmatova, Nelli K.; Kurbatova, Ekaterina A.; Akhmatov, Elvin A.; Egorova, Nadezhda B.; Logunov, Denis Yu.; Gening, Marina L.; Sukhova, Elena V.; Yashunsky, Dmitry V.; Tsvetkov, Yury E.; Nifantiev, Nikolay E.

    2016-01-01

    We report the effect of a bovine serum albumin (BSA) conjugate of a synthetic hexasaccharide (HS) related to the fragment of the capsular polysaccharide (PS) of Streptococcus pneumoniae type 14 on the stimulation of innate immune system and the subsequent development of a PS-specific antibody response. Glycoconjugate (GC) in the presence (GC + AL) or absence of aluminum hydroxide was administered to mice twice. GC increased the number of TLR2-expressing cells and induced the maturation of dendritic cells (CD11c+, CD80+ and, MHCII+), which secreted IL-1β, IL-6, and TNFα into the culture medium. The level of IL-1β, IL-10, IFNγ, and TNFα in the blood increased within 24 h after the single GC administration to mice. On day 7, the numbers of splenic CD4+ and CD8+ T lymphocytes and B lymphocytes increased. After the second immunization, the levels of CD4+ and CD8+ T lymphocytes were lower than in the control, whereas the B cell, NK cell, and MHC class II-expressing cell numbers remained enhanced. However, of the presence of anti-PS, IgG antibodies were not detected. The addition of aluminum hydroxide to GC stimulated the production of GM-CSF, IL-1β, IL-5, IL-6, IL-10, IL-17, IFNγ, and TNFα. Anti-PS IgG1 antibody titers 7 days after the second immunization were high. During that period, normal levels of splenic CD4+ T lymphocytes were maintained, whereas reduced CD8+ T lymphocyte numbers and increased levels of B lymphocytes, NK cells, and MHC class II-expressing cell numbers were observed. Anti-PS IgG levels diminished until day 92. A booster immunization with GC + AL stimulated the production of anti-PS IgG memory antibodies, which were determined within 97 days. The elucidation of specific features of the effect of the synthetic HS conjugate on the stimulation of innate, cell-mediated immunity, and antibody response can favor the optimization of GC vaccine design. PMID:27446078

  11. Sequence diversity within the capsular genes of Streptococcus pneumoniae serogroup 6 and 19.

    PubMed

    Elberse, Karin; Witteveen, Sandra; van der Heide, Han; van de Pol, Ingrid; Schot, Corrie; van der Ende, Arie; Berbers, Guy; Schouls, Leo

    2011-01-01

    The main virulence factor of Streptococcus pneumoniae is the capsule. The polysaccharides comprising this capsule are encoded by approximately 15 genes and differences in these genes result in different serotypes. The aim of this study was to investigate the sequence diversity of the capsular genes of serotypes 6A, 6B, 6C, 19A and 19F and to explore a possible effect of vaccination on variation and distribution of these serotypes in the Netherlands. The complete capsular gene locus was sequenced for 25 serogroup 6 and for 20 serogroup 19 isolates. If one or more genes varied in 10 or more base pairs from the reference sequence, it was designated as a capsular subtype. Allele-specific PCRs and specific gene sequencing of highly variable capsular genes were performed on 184 serogroup 6 and 195 serogroup 19 isolates to identify capsular subtypes. This revealed the presence of 6, 3 and a single capsular subtype within serotypes 6A, 6B and 6C, respectively. The serotype 19A and 19F isolates comprised 3 and 4 capsular subtypes, respectively. For serogroup 6, the genetic background, as determined by multi locus sequence typing (MLST) and multiple-locus variable number of tandem repeat analysis (MLVA), seemed to be closely related to the capsular subtypes, but this was less pronounced for serogroup 19 isolates. The data also suggest shifts in the occurrence of capsular subtypes within serotype 6A and 19A after introduction of the 7-valent pneumococcal vaccine. The shifts within these non-vaccine serotypes might indicate that these capsular subtypes are filling the niche of the vaccine serotypes. In conclusion, there is considerable DNA sequence variation of the capsular genes within pneumococcal serogroup 6 and 19. Such changes may result in altered polysaccharides or in strains that produce more capsular polysaccharides. Consequently, these altered capsules may be less sensitive for vaccine induced immunity.

  12. Observation of the helical structure of the bacterial polysaccharide acetan by atomic force microscopy.

    PubMed Central

    Kirby, A R; Gunning, A P; Morris, V J; Ridout, M J

    1995-01-01

    A method has been developed that has been found to give reproducible images of uncoated polysaccharides by Atomic Force Microscopy (AFM). Aqueous solutions of the polysaccharide are deposited as drops onto freshly cleaved mica surfaces, air dried, and then imaged under butanol. The method has been used to obtain images of the bacterial polysaccharide acetan. In regions within the deposited sample, where the molecules are aligned side-by-side, it has been possible to observe a periodic structure along the polysaccharide chain, attributable to the helical structure of acetan. Images FIGURE 1 FIGURE 3 FIGURE 4 PMID:7711262

  13. Optimization of polysaccharides extraction from watermelon rinds: Structure, functional and biological activities.

    PubMed

    Romdhane, Molka Ben; Haddar, Anissa; Ghazala, Imen; Jeddou, Khawla Ben; Helbert, Claire Boisset; Ellouz-Chaabouni, Semia

    2017-02-01

    In the present work, optimization of hot water extraction, structural characteristics, functional properties, and biological activities of polysaccharides extracted from watermelon rinds (WMRP) were investigated. The physicochemical characteristics and the monosaccharide composition of these polysaccharides were then determined using chemical composition analysis, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and gas chromatography-flame ionization detection (GC-FID). SEM images showed that extracted polysaccharides had a rough surface with many cavities. GC-FID results proved that galactose was the dominant sugar in the extracted polysaccharides, followed by arabinose, glucose, galacturonic acid, rhamnose, mannose, xylose and traces of glucuronic acid. The findings revealed that WMRP displayed excellent antihypertensive and antioxidant activities. Those polysaccharides had also a protection effect against hydroxyl radical-induced DNA damage. Functional properties of extracted polysaccharides were also evaluated. WMRP showed good interfacial dose-dependent proprieties. Overall, the results suggested that WMRP presents a promising natural source of antioxidants and antihypertensive agents.

  14. [The structure of the glycerophosphate-containing O-specific polysaccharide from Escherichia coli 0130].

    PubMed

    Perepelov, A V; Lu, B; Sebchenkova, S N; Shevelev, S D; Wang, V; Shashkov, A S; Feng, L; Wang, L; Knirel', Iu A

    2007-01-01

    A phosphorylated O-specific polysaccharide was obtained by mild acidic degradation of the lipopolysaccharide from the intestinal bacterium Escherichia coli 0130 and characterized by the methods of chemical analysis, including dephosphorylation, and 1H and 13C NMR spectroscopy. The polysaccharide was shown to be composed of branched tetrasaccharide repeating units containing two N-acetyl-D-galactosamine residues, D-galactose, D-glucose, and glycerophosphate residues (one of each). The polysaccharide has the following structure, which is unique among the known bacterial polysaccharides.

  15. Structural insights into antibody recognition of mycobacterial polysaccharides.

    PubMed

    Murase, Tomohiko; Zheng, Ruixiang Blake; Joe, Maju; Bai, Yu; Marcus, Sandra L; Lowary, Todd L; Ng, Kenneth K S

    2009-09-18

    Mycobacteria are major human pathogens responsible for such serious and widespread diseases as tuberculosis and leprosy. Among the evolutionary adaptations essential for pathogenicity in mycobacteria is a complex carbohydrate-rich cell-wall structure that contains as a major immunomodulatory molecule the polysaccharide lipoarabinomannan (LAM). We report here crystal structures of three fragments from the non-reducing termini of LAM in complex with a murine antibody Fab fragment (CS-35Fab). These structures reveal for the first time the three-dimensional structures of key components of LAM and the molecular basis of LAM recognition at between 1.8- and 2.0-A resolution. The antigen-binding site of CS-35Fab forms three binding pockets that show a high degree of complementarity to the reducing end, the branch point and one of the non-reducing ends of the Y-shaped hexasaccharide moiety found at most of the non-reducing termini of LAM. Structures of CS-35Fab bound to two additional tetrasaccharides confirm the general mode of binding seen in the hexasaccharide and indicate how different parts of LAM are recognized. Altogether, these structures provide a rational basis for understanding the overall architecture of LAM and identify the key elements of an epitope that may be exploited for the development of novel and more effective anti-mycobacterial vaccines. Moreover, this study represents the first high-resolution X-ray crystallographic investigation of oligofuranoside-protein recognition.

  16. Split of Chiral Degeneracy in Mechanical and Structural Properties of Oligopeptide-Polysaccharide Biomaterials

    SciTech Connect

    Taraban, Marc B.; Hyland, Laura L.; Yu, Y. Bruce

    2013-09-23

    Enantiomeric biomaterials which are mirror images of each other are characterized by chiral degeneracy—identical structural characteristics and bulk material properties. The addition of another chiral component, d-polysaccharide, has been shown to split such degeneracy and result in two distinct biomaterials. Dynamic oscillatory rheometry and small-angle X-ray scattering demonstrate that the natural biochirality combination of l-peptides and d-polysaccharides assembles faster, has higher elastic moduli (G'), and is structurally more beneficial as opposed to the alternative d-peptide and d-polysaccharide combination. Chemical modifications of the OH-groups in α-d-glucose units in d-polysaccharides weaken such splitting of chiral degeneracy. These findings form a basis to design novel biomaterials and provide additional insight on why proteins and polysaccharides have oppoiste chirality in the biological world.

  17. Capsule structure of Proteus mirabilis (ATCC 49565).

    PubMed Central

    Beynon, L M; Dumanski, A J; McLean, R J; MacLean, L L; Richards, J C; Perry, M B

    1992-01-01

    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. PMID:1551839

  18. Advances in antitumor polysaccharides from phellinus sensu lato: Production, isolation, structure, antitumor activity, and mechanisms.

    PubMed

    Yan, Jing-Kun; Pei, Juan-Juan; Ma, Hai-Le; Wang, Zhen-Bin; Liu, Yuan-Shuai

    2017-04-13

    Edible and medicinal fungi (mushrooms) are widely applied to functional foods and nutraceutical products because of their proven nutritive and medicinal properties. Phellinus sensu lato is a well-known medicinal mushroom that has long been used in preventing ailments, including gastroenteric dysfunction, diarrhea, hemorrhage, and cancers, in oriental countries, particularly in China, Japan, and Korea. Polysaccharides represent a major class of bioactive molecules in Phellinus s. l., which have notable antitumor, immunomodulatory, and medicinal properties. Polysaccharides that were isolated from fruiting bodies, cultured mycelia, and filtrates of Phellinus s. l. have not only activated different immune responses of the host organism but have also directly suppressed tumor growth and metastasis. Studies suggest that polysaccharides from Phellinus s. l. are promising alternative anticancer agents or synergizers for existing antitumor drugs. This review summarizes the recent development of polysaccharides from Phellinus s. l., including polysaccharide production, extraction and isolation methods, chemical structure, antitumor activities, and mechanisms of action.

  19. Structure and organization of phospholipid/polysaccharide nanoparticles

    NASA Astrophysics Data System (ADS)

    Gerelli, Y.; Di Bari, M. T.; Deriu, A.; Cantù, L.; Colombo, P.; Como, C.; Motta, S.; Sonvico, F.; May, R.

    2008-03-01

    In recent years nanoparticles and microparticles composed of polymeric or lipid material have been proposed as drug carriers for improving the efficacy of encapsulated drugs. For the production of these systems different materials have been proposed, among them phospholipids and polysaccharides due to their biocompatibility, biodegradability, low cost and safety. We report here a morphological and structural investigation, performed using cryo-TEM, static light scattering and small angle neutron and x-ray scattering, on phospholipid/saccharide nanoparticles loaded with a lipophilic positively charged drug (tamoxifen citrate) used in breast cancer therapy. The lipid component was soybean lecithin; the saccharide one was chitosan that usually acts as an outer coating increasing vesicle stability. The microscopy and scattering data indicate the presence of two distinct nanoparticle families: uni-lamellar vesicles with average radius 90 Å and multi-lamellar vesicles with average radius 440 Å. In both families the inner core is occupied by the solvent. The presence of tamoxifen gives rise to a multi-lamellar structure of the lipid outer shell. It also induces a positive surface charge into the vesicles, repelling the positively charged chitosan molecules which therefore do not take part in nanoparticle formation.

  20. Antibody Binding to Cryptococcus neoformans Impairs Budding by Altering Capsular Mechanical Properties

    PubMed Central

    Cordero, Radames J. B.; Pontes, Bruno; Frases, Susana; Nakouzi, Antonio S.; Nimrichter, Leonardo; Rodrigues, Marcio L.; Viana, Nathan B.

    2013-01-01

    Abs to microbial capsules are critical for host defense against encapsulated pathogens, but very little is known about the effects of Ab binding on the capsule, apart from producing qualitative capsular reactions (“quellung” effects). A problem in studying Ab–capsule interactions is the lack of experimental methodology, given that capsules are fragile, highly hydrated structures. In this study, we pioneered the use of optical tweezers microscopy to study Ab–capsule interactions. Binding of protective mAbs to the capsule of the fungal pathogen Cryptococcus neoformans impaired yeast budding by trapping newly emerging buds inside the parental capsule. This effect is due to profound mAb-mediated changes in capsular mechanical properties, demonstrated by a concentration-dependent increase in capsule stiffness. This increase involved mAb-mediated cross-linking of capsular polysaccharide molecules. These results provide new insights into Ab-mediated immunity, while suggesting a new nonclassical mechanism of Ab function, which may apply to other encapsulated pathogens. Our findings add to the growing body of evidence that Abs have direct antimicrobial functions independent of other components of the immune system. PMID:23233725

  1. Structural characterization and biomedical properties of sulfated polysaccharide from the gladius of Sepioteuthis lessoniana (Lesson, 1831).

    PubMed

    Seedevi, Palaniappan; Moovendhan, Meivelu; Vairamani, Shanmugam; Shanmugam, Annian

    2016-04-01

    Sulfated polysaccharide was extracted from the internal shell (gladius) of Sepioteuthis lessoniana. The sulfated polysaccharide contained 61.3% of carbohydrate, 0.8% of protein, 28.2% of ash and 1.33% of moisture respectively. The elemental composition was analyzed using CHNS/O analyzer. The molecular weight of sulfated polysaccharide determined through PAGE was found to be as 66 kDa. Monosaccharides analysis revealed that sulfated polysaccharide was composed of rhamnose, galactose, xylose and glucose. The structural features of sulfated polysaccharide were analyzed by FT-IR and NMR spectroscopy. Further the sulfated polysaccharide was evaluated for its antibacterial activity against selected human clinical pathogens, namely Staphylococcus aureus, Klebsiella pneumoniae, Salmonella typhi, Vibrio cholerae, Klebsiella oxytoca, Escherichia coli, Salmonella paratyphi, Proteus mirabilis, Vibrio parahaemolyticus and Streptococcus pyogenes using agar well diffusion method. The polysaccharide has showed good antibacterial activity and MIC and MBC have also been evaluated. The anticancer activity was tested against HeLa cell line by MTT assay. The Cytotoxic Concentration (CC50) was observed as 700 μg/ml and the maximum anticancer activity of 62.89% was recorded at 200 μg/ml; whereas, the lowest of 9.87% was observed at 25 μg/ml. In conclusion, the sulfated polysaccharide is an alternate, non-toxic and cheap source of substance that showed good antibacterial and anticancer acitivity.

  2. New structure for the O-polysaccharide of Providencia alcalifaciens O27 and revised structure for the O-polysaccharide of Providencia stuartii O43.

    PubMed

    Ovchinnikova, Olga G; Bushmarinov, Ivan S; Kocharova, Nina A; Toukach, Filip V; Wykrota, Marianna; Shashkov, Alexander S; Knirel, Yuriy A; Rozalski, Antoni

    2007-06-11

    The O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide from Providencia alcalifaciens O27 and studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including 2D (1)H,(1)H COSY, TOCSY, ROESY, H-detected (1)H,(13)C HSQC, and HMBC experiments. It was found that the polysaccharide is built up of linear partially O-acetylated tetrasaccharide repeating units and has the following structure: [structure: see text] where Qui4NFo stands for 4-formamido-4,6-dideoxyglucose (4-formamido-4-deoxyquinovose). The O-polysaccharide structure of Providencia stuartii O43 established earlier was revised with respect to the configuration of the constituent 4-amino-4,6-dideoxyhexose (from Rha4N to Qui4N).

  3. Structure of the O-polysaccharide from the lipopolysaccharide of Providencia alcalifaciens O33.

    PubMed

    Ovchinnikova, Olga G; Shashkov, Alexander S; Chizhov, Alexander O; Moryl, Magdalena; Rozalski, Antoni; Knirel, Yuriy A

    2014-05-22

    Mild acid degradation of the lipopolysaccharide from Providencia alcalifaciens O33 resulted in an O-polysaccharide along with core and O-unit-bearing core oligosaccharides. Composition of the oligosaccharides was inferred by ESI mass spectrometry. Based on sugar and methylation analyses, Smith degradation and (1)H and (13)C NMR spectroscopy data, the following structure of the tetrasaccharide O-unit of the O-polysaccharide was established: Another O-polysaccharide structure has been reported earlier for Providencia stuartii О33 but later found to belong to a P. stuartii О52 strain.

  4. Effect of extraction method on structure and antioxidant activity of Hohenbuehelia serotina polysaccharides.

    PubMed

    Li, Xiaoyu; Wang, Lu

    2016-02-01

    The impacts of four extraction methods (hot water, enzyme assistance, ultrasonic assistance and ultrasonic-enzyme assistance) on the extraction yields, preliminary structure and antioxidant activities of the Hohenbuehelia serotina polysaccharides (HW-HSP, EA-HSP, UA-HSP and UEA-HSP) were systematically investigated. The yield of the polysaccharides (20.70±0.17%) obtained by ultrasonic-enzyme assistance was higher than the polysaccharides by other methods'. Four kinds of polysaccharides possessed the different preliminary structural characteristics including molecular weight distributions, monosaccharide compositions, crystallization and spiral structures, while different surface morphology. Through the measurements of antioxidant activities in vitro, UEA-HSP exhibited the most significant scavenging capacities on non-physiological ABTS free radicals and physiological hydroxyl radicals. These data showed that ultrasonic-enzyme assistance was more beneficial to enhance the extraction yields of the polysaccharides, and obtain higher bioactive polysaccharides. The results also suggested that H. serotina polysaccharides possessed potential healthcare application in food field due to their antioxidant activities.

  5. Regioselective sulfation of Artemisia sphaerocephala polysaccharide: Characterization of chemical structure.

    PubMed

    Wang, Junlong; Yang, Wen; Wang, Jiancheng; Wang, Xia; Wu, Fang; Yao, Jian; Zhang, Ji; Lei, Ziqiang

    2015-11-20

    The biological activities of sulfated polysaccharides are related to the substitution positions of functional groups. In this study, regioselective sulfation of Artemisia sphaerocephala polysaccharides (SRSASP) was prepared by using triphenylchloromethane (TrCl) as protecting precursor. FT-IR spectra and X-ray photoelectron spectroscopy (XPS) showed that SO(3-) group (S(6+), high binding energy of 168.7eV) was widely present in sulfated polysaccharides. (13)C NMR spectroscopy showed that C-2 and C-3 substitution was occurred but not fully sulfation. Meanwhile, C-6 substituted signals near 65ppm were not observed. The degree of substitution varied from 0.44 to 0.63 in SRSASP which could be attributed to the low reactivity at secondary hydroxyl. Monosaccharide composition result showed a decrease in the ratio of mannose/glucose, indicating the change of chemical composition in sulfated polysaccharides. In size-exclusion chromatograph analysis, a decrease in molecular weight and broadening of molecular weight distribution of sulfated polysaccharides was also observed. It could be attributed to the hydrolysis of polysaccharide in the sulfated reaction.

  6. The structure of the O-polysaccharide from the lipopolysaccharide of Providencia stuartii O47.

    PubMed

    Ovchinnikova, Olga G; Kocharova, Nina A; Bakinovskiy, Leon V; Torzewska, Agnieszka; Shashkov, Alexander S; Knirel, Yuriy A; Rozalski, Antoni

    2004-10-20

    The O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Providencia stuartii O47:H4, strain 3646/51. Studies by sugar and methylation analyses along with Smith degradation and 1H and 13C NMR spectroscopy, including two-dimensional 1H,1H COSY, TOCSY, ROESY and H-detected 1H,13C HSQC and HMBC experiments, showed that the polysaccharide has a branched hexasaccharide repeating unit with the following structure: [carbohydrate structure: see text

  7. Structure of complex cell wall polysaccharides isolated from Trichoderma and Hypocrea species.

    PubMed

    Prieto, A; Leal, J A; Poveda, A; Jiménez-Barbero, J; Gómez-Miranda, B; Domenech, J; Ahrazem, O; Bernabé, M

    1997-11-28

    The structure of fungal polysaccharides isolated from the cell wall of Trichoderma reesei, T. koningii, and Hypocrea psychrophila, have been investigated by means of chemical analyses and 1D and 2D NMR spectroscopy. The polysaccharides have an irregular structure, idealized as follows: [formula: see text] The proportions of the different side chains vary from a species to another, being n above some three times larger in H. psychrophila than in T. reesei or T. koningii.

  8. Structural characterization of an acidic polysaccharide from Dalbergia sissoo Roxb. leaves.

    PubMed

    Rana, Vikas; Kumar, Vineet; Soni, P L

    2012-09-01

    The composition and structure of an acidic polysaccharide from the leaves of Dalbergia sissoo was studied using hydrolytic, methylation, (1)H/(13)C heteronuclear multiple quantum coherence (HMQC) and periodate oxidation experiments. The repeating unit of sissoo polysaccharide was found to be composed of α-L-rhamnose, β-D-glucuronic acid, β-D-galactose and β-D-glucose in the molar ratio of 1.00:1.00:2.00:2.33, respectively. The structure of polysaccharide was mainly composed of (1→2), (1→3), (1→4) linkages. Based on extensive laboratory experiments, the structure having the repeating units of the acidic polysaccharide from sissoo leaves, with unusual branching, was established.

  9. Structural identification and cytotoxic activity of a polysaccharide from the fruits of Lagenaria siceraria (Lau).

    PubMed

    Ghosh, Kaushik; Chandra, Krishnendu; Ojha, Arnab K; Sarkar, Siddik; Islam, Syed S

    2009-03-31

    A water-soluble polysaccharide, isolated from fruiting bodies of Lagenaria siceraria, is composed of methyl-alpha-d-galacturonate, 3-O-acetyl methyl-alpha-d-galacturonate, and beta-d-galactose in a ratio of nearly 1:1:1. Compositional analysis, methylation analysis, periodate oxidation, and NMR studies ((1)H, (13)C, 2D-COSY, TOCSY, NOESY, HMQC, and HMBC) revealed the presence of the following repeating unit in the polysaccharide: [carbohydrate structure: see text] This polysaccharide showed cytotoxic activity in vitro against human breast adenocarcinoma cell line (MCF-7).

  10. PolySac3DB: an annotated data base of 3 dimensional structures of polysaccharides

    PubMed Central

    2012-01-01

    Background Polysaccharides are ubiquitously present in the living world. Their structural versatility makes them important and interesting components in numerous biological and technological processes ranging from structural stabilization to a variety of immunologically important molecular recognition events. The knowledge of polysaccharide three-dimensional (3D) structure is important in studying carbohydrate-mediated host-pathogen interactions, interactions with other bio-macromolecules, drug design and vaccine development as well as material science applications or production of bio-ethanol. Description PolySac3DB is an annotated database that contains the 3D structural information of 157 polysaccharide entries that have been collected from an extensive screening of scientific literature. They have been systematically organized using standard names in the field of carbohydrate research into 18 categories representing polysaccharide families. Structure-related information includes the saccharides making up the repeat unit(s) and their glycosidic linkages, the expanded 3D representation of the repeat unit, unit cell dimensions and space group, helix type, diffraction diagram(s) (when applicable), experimental and/or simulation methods used for structure description, link to the abstract of the publication, reference and the atomic coordinate files for visualization and download. The database is accompanied by a user-friendly graphical user interface (GUI). It features interactive displays of polysaccharide structures and customized search options for beginners and experts, respectively. The site also serves as an information portal for polysaccharide structure determination techniques. The web-interface also references external links where other carbohydrate-related resources are available. Conclusion PolySac3DB is established to maintain information on the detailed 3D structures of polysaccharides. All the data and features are available via the web

  11. Catalytic synthesis of sulfated polysaccharides I: Characterization of chemical structure.

    PubMed

    Wang, Junlong; Yang, Wen; Yang, Ting; Zhang, Xiaonuo; Zuo, Yuan; Tian, Jia; Yao, Jian; Zhang, Ji; Lei, Ziqiang

    2015-03-01

    In the present study, sulfated derivatives of Artemisia sphaerocephala polysaccharide (SASP) with high degree of substitution (DS) were synthesized by using 4-dimethylaminopyridine (DMAP)/dimethylcyclohexylcarbodiimide (DCC) as catalyst in homogeneous conditions. It was found that DMAP/DCC showed marked improvement in DS of sulfated samples. Compared to sulfated derivatives without catalyst, the DS of SASP increased from 0.91 to 1.28 with an increment in dosage of DMAP from 0 to 10 mg. The influence of DMAP/DCC on the DS of sulfated derivatives was depended on the content of DMAP. The effect of DMAP might be due to its strong coordination to the hydroxy group. The results of FT-IR and X-ray photoelectron spectroscopy (XPS) indicated that SO3- group (S6+, binding energy of 172.3 eV) was widely present in sulfated polysaccharide molecules. 13C NMR results indicated that C-6 substitution was predominant for sulfated polysaccharide when compared with other positions. In the sulfation reaction, a sharp decrease in MW was observed. DMAP/DCC was an effective catalyst system in sulfated modification of polysaccharide.

  12. Extraction, Structural Characterization, and Potential Antioxidant Activity of the Polysaccharides from Four Seaweeds.

    PubMed

    He, Jinzhe; Xu, Yaoyang; Chen, Hongbo; Sun, Peilong

    2016-11-28

    Four seaweed polysaccharides were extracted from Sarcodia ceylonensis, Ulva lactuca L., Gracilaria lemaneiformis, and Durvillaea antarctica, respectively, by microwave-assisted extraction. The effect of three significant variables (extraction time, extraction temperature, and the ratio of water to raw material) on the process for extracting polysaccharides was investigated, along with the optimization of the extraction using the response surface method (RSM) with a Box-Behnken design. The polysaccharide structure, monosaccharide composition, degree of sulfation, and molecular weight (MW) distribution were analyzed by infrared (IR) spectrometry, gas chromatography (GC), and high-performance gel permeation chromatography (HPGPC). IR spectrometry showed that Sarcodia ceylonensis polysaccharide (SCP), Ulva lactuca L. polysaccharide (ULLP), and Durvillaea antarctica polysaccharide (DAP) were all sulfated polysaccharides and, except Gracilaria lemaneiformis polysaccharide (GLP), all belong to β-pyranosidic polysaccharides. The average molecular weight (MW) of SCP, ULLP, GLP, and DAP was 466, 404, 591, and 482 kDa, respectively. The quantitative and comparative results with external standards indicated that the main monosaccharide in SCP and ULLP was mannose; and GLP and DAP were mainly composed of galactose and glucose, respectively. Then the in vitro antioxidant activity of all of the polysaccharides was evaluated using different assays-2,2-azino -bis (3-ethylbenzthiazoline-6- sulfonate) (ABTS), hydroxyl radical, nitrite scavenging capacity, and reducing power-and the relationship between their antioxidant activity and chemical characteristics were also examined. ULLP presented the highest ABTS radical scavenging activity; ULLP, SCP and DAP also showed a strong effect on the ABTS radical scavenging activity. SCP and ULLP exhibited excellent hydroxyl radical scavenging activities, about 83.33% ± 2.31% and 80.07% ± 2.17%, respectively, at 4 mg/mL. The reducing power of

  13. Extraction, Structural Characterization, and Potential Antioxidant Activity of the Polysaccharides from Four Seaweeds

    PubMed Central

    He, Jinzhe; Xu, Yaoyang; Chen, Hongbo; Sun, Peilong

    2016-01-01

    Four seaweed polysaccharides were extracted from Sarcodia ceylonensis, Ulva lactuca L., Gracilaria lemaneiformis, and Durvillaea antarctica, respectively, by microwave-assisted extraction. The effect of three significant variables (extraction time, extraction temperature, and the ratio of water to raw material) on the process for extracting polysaccharides was investigated, along with the optimization of the extraction using the response surface method (RSM) with a Box–Behnken design. The polysaccharide structure, monosaccharide composition, degree of sulfation, and molecular weight (MW) distribution were analyzed by infrared (IR) spectrometry, gas chromatography (GC), and high-performance gel permeation chromatography (HPGPC). IR spectrometry showed that Sarcodia ceylonensis polysaccharide (SCP), Ulva lactuca L. polysaccharide (ULLP), and Durvillaea antarctica polysaccharide (DAP) were all sulfated polysaccharides and, except Gracilaria lemaneiformis polysaccharide (GLP), all belong to β-pyranosidic polysaccharides. The average molecular weight (MW) of SCP, ULLP, GLP, and DAP was 466, 404, 591, and 482 kDa, respectively. The quantitative and comparative results with external standards indicated that the main monosaccharide in SCP and ULLP was mannose; and GLP and DAP were mainly composed of galactose and glucose, respectively. Then the in vitro antioxidant activity of all of the polysaccharides was evaluated using different assays—2,2–azino –bis (3-ethylbenzthiazoline-6- sulfonate) (ABTS), hydroxyl radical, nitrite scavenging capacity, and reducing power—and the relationship between their antioxidant activity and chemical characteristics were also examined. ULLP presented the highest ABTS radical scavenging activity; ULLP, SCP and DAP also showed a strong effect on the ABTS radical scavenging activity. SCP and ULLP exhibited excellent hydroxyl radical scavenging activities, about 83.33% ± 2.31% and 80.07% ± 2.17%, respectively, at 4 mg/mL. The

  14. Sulfated polysaccharides from brown seaweeds Saccharina japonica and Undaria pinnatifida: isolation, structural characteristics, and antitumor activity.

    PubMed

    Vishchuk, Olesya S; Ermakova, Svetlana P; Zvyagintseva, Tatyana N

    2011-12-13

    During the last decade brown seaweeds attracted much attention as a source of polysaccharides, namely laminarans, alginic acids, and sulfated polysaccharides-fucoidans, with various structures and biological activities. In this study, sulfated polysaccharides were isolated from brown seaweeds Saccharina japonica (formerly named Laminaria) and Undaria pinnatifida and their antitumor activity was tested against human breast cancer T-47D and melanoma SK-MEL-28 cell lines. The sulfated polysaccharide form S. japonica was highly branched partially acetylated sulfated galactofucan, built up of (1→3)-α-L-fucose residues. The sulfated polysaccharide from U. pinnatifida was partially acetylated highly sulfated galactofucan consisting of (1→3)- or (1→3);(1→4)-α-L-fucose residues. Fucoidans from S. japonica and U. pinnatifida distinctly inhibited proliferation and colony formation in both breast cancer and melanoma cell lines in a dose-dependent manner. These results indicated that the use of sulfated polysaccharides from brown seaweeds S. japonica and U. pinnatifida might be a potential approach for cancer treatment.

  15. New structures of the O-specific polysaccharides of Proteus. 3. Polysaccharides containing non-carbohydrate organic acids.

    PubMed

    Kondakova, A N; Toukach, F V; Senchenkova, S N; Arbatsky, N P; Shashkov, A S; Knirel, Y A; Bartodziejska, B; Zych, K; Rozalski, A; Sidorczyk, Z

    2003-04-01

    Four new Proteus O-specific polysaccharides were isolated by mild acid degradation from the lipopolysaccharides of P. penneri 28 (1), P. vulgaris O44 (2), P. mirabilis G1 (O3) (3), and P. myxofaciens (4), and their structures were elucidated using NMR spectroscopy and chemical methods. They were found to contain non-carbohydrate organic acids, including ether-linked lactic acid and amide-linked amino acids, and the following structures of the repeating units were established: [Figure: see text], where (S)-Lac and (R)-aLys stand for (S)-1-carboxyethyl (residue of lactic acid) and N(epsilon)-[(R)-1-carboxyethyl]-L-lysine ("alaninolysine"), respectively. The data obtained in this work and earlier serve as the chemical basis for classification of the bacteria Proteus.

  16. Structure characteristics of a water-soluble polysaccharide purified from dragon fruit (Hylocereus undatus) pulp.

    PubMed

    Xu, Lishan; Zhang, Yaojie; Wang, Lizhi

    2016-08-01

    Dragon fruit is a tropical fruit with good taste. It can bring health benefits to human body. As one of the major bioactive components in this fruit, the polysaccharides might contribute to the health benefits. However, the precise structure information remains unknown. A leading polysaccharide of dragon fruit pulp, DFPP, was purified and identified by NMR and GC-MS. →4-β-d-GlcpA-1→, →6-β-d-Galp-1→ and →4-α-l-Rhap-1→ constituted the backbone and α-l-Araf-1→5-α-l-Araf-1→ formed the branch chain. The precise structure was putatively identified as below. The molecular weight was 2.2×10(3)kDa. The structure information of polysaccharides will be helpful to understand this fruit.

  17. Structures of three different neutral polysaccharides of Acinetobacter baumannii, NIPH190, NIPH201, and NIPH615, assigned to K30, K45, and K48 capsule types, respectively, based on capsule biosynthesis gene clusters.

    PubMed

    Shashkov, Alexander S; Kenyon, Johanna J; Arbatsky, Nikolay P; Shneider, Mikhail M; Popova, Anastasiya V; Miroshnikov, Konstantin A; Volozhantsev, Nikolay V; Knirel, Yuriy A

    2015-11-19

    Neutral capsular polysaccharides (CPSs) were isolated from Acinetobacter baumannii NIPH190, NIPH201, and NIPH615. The CPSs were found to contain common monosaccharides only and to be branched with a side-chain 1→3-linked β-d-glucopyranose residue. Structures of the oligosaccharide repeat units (K units) of the CPSs were elucidated by 1D and 2D (1)H and (13)C NMR spectroscopy. Novel CPS biosynthesis gene clusters, designated KL30, KL45, and KL48, were found at the K locus in the genome sequences of NIPH190, NIPH201, and NIPH615, respectively. The genetic content of each gene cluster correlated with the structure of the CPS unit established, and therefore, the capsular types of the strains studied were designated as K30, K45, and K48, respectively. The initiating sugar of each K unit was predicted, and glycosyltransferases encoded by each gene cluster were assigned to the formation of the linkages between sugars in the corresponding K unit.

  18. [Structural characterization of Astragalus polysaccharides using partial acid hydrolysis-hydrophilic interaction liquid chromatography-mass spectrometry].

    PubMed

    Liang, Tu; Fu, Qing; Xin, Huaxia; Li, Fangbing; Jin, Yu; Liang, Xinmiao

    2014-12-01

    Water-soluble polysaccharides from traditional Chinese medicine (TCM) have properties of broad-spectrum treatment and low toxicity, making them as important components in natural medicines and health products. In order to solve the problem of polysaccharides characterization caused by their complex structures, a "bottom-up" approach was developed to complete the characterization of polysaccharides from Astragalus. Firstly, Astragalus pieces were extracted with hot water and then were precipitated by ethanol to obtain Astragalus polysaccharides. Secondly, a partial acid hydrolysis method was carried out and the effects of time, acid concentration and temperature on hydrolysis were investigated. The degree of hydrolysis increased along with the increase of hydrolysis time and acid concentration. The temperature played a great role in the hydrolysis process. No hydrolysis of the polysaccharides occurred at low temperature, while the polysaccharides were almost hydrolyzed to monosaccharide at high temperature. Under the optimum hydrolysis conditions (4 h, 1.5 mol/L trifluoroacetic acid, and 80 °C), Astragalus polysaccharides were hydrolyzed to characteristic oligosaccharide fragments. At last, a hydrophilic liquid chromatography-mass spectrometry method was used for the separation and structural characterization of the polysaccharide hydrolysates. The results showed that the resulting polysaccharides were mainly 1--> 4 linear glucan, and gluco-oligosaccharides with the degrees of polymerization (DP) of 4 - 11 were obtained after partial acid hydrolysis. The significance of this study is that it is the guidance for the characterization of other TCM polysaccharides.

  19. Structure and boosting activity of a starch-degrading lytic polysaccharide monooxygenase.

    PubMed

    Lo Leggio, Leila; Simmons, Thomas J; Poulsen, Jens-Christian N; Frandsen, Kristian E H; Hemsworth, Glyn R; Stringer, Mary A; von Freiesleben, Pernille; Tovborg, Morten; Johansen, Katja S; De Maria, Leonardo; Harris, Paul V; Soong, Chee-Leong; Dupree, Paul; Tryfona, Theodora; Lenfant, Nicolas; Henrissat, Bernard; Davies, Gideon J; Walton, Paul H

    2015-01-22

    Lytic polysaccharide monooxygenases (LPMOs) are recently discovered enzymes that oxidatively deconstruct polysaccharides. LPMOs are fundamental in the effective utilization of these substrates by bacteria and fungi; moreover, the enzymes have significant industrial importance. We report here the activity, spectroscopy and three-dimensional structure of a starch-active LPMO, a representative of the new CAZy AA13 family. We demonstrate that these enzymes generate aldonic acid-terminated malto-oligosaccharides from retrograded starch and boost significantly the conversion of this recalcitrant substrate to maltose by β-amylase. The detailed structure of the enzyme's active site yields insights into the mechanism of action of this important class of enzymes.

  20. Structure of the O-polysaccharide of Escherichia coli O132.

    PubMed

    Shashkov, Alexander S; Zhang, Wenwen; Perepelov, Andrei V; Weintraub, Andrej; Liu, Bin; Widmalm, Göran; Knirel, Yuriy A

    2016-06-02

    Mild acid degradation of the lipopolysaccharide of Escherichia coli O132 released its O-polysaccharide. Analysis by 1D and 2D (1)H and (13)C NMR spectroscopy prior and subsequent to O-deacetylation, in conjunction with sugar analysis, revealed a linear pentasaccharide repeating unit of the O-polysaccharide having the following structure: →2)-α-d-Galf-(1→3)-α-l-Rhap2Ac-(1→4)-α-d-Glcp-(1→2)-α-l-Rhap-(1→3)-β-d-GlcpNAc-(1→ Putative functions of genes in the O-antigen gene cluster of E. coli O132 are consistent with the O-polysaccharide structure.

  1. Structure of the O-specific polysaccharide of the bacterium Proteus vulgaris O23.

    PubMed

    Perepelov, A V; Shashkov, A S; Babichka, D; Senchenkova, S N; Bartodziejska, B; Rozalski, A; Knirel, Y A

    2000-09-01

    An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of the bacterium Proteus vulgaris O23 (strain PrK 44/57) and found to contain 2-acetamido-2-deoxy-D-galactose, 2-acetamido-2-deoxy-D-glucose, and D-galacturonic acid. Based on 1H- and 13C-NMR spectroscopic studies, including two-dimensional correlation spectroscopy (COSY), total correlation spectroscopy (TOCSY), nuclear Overhauser effect spectroscopy (NOESY), and 1H,13C heteronuclear multiple-quantum coherence (HMQC) experiments, the following structure of the branched tetrasaccharide repeating unit of the polysaccharide was established: [figure], where the degree of O-acetylation of the terminal GalA residue at position 4 is about 80%. A structural similarity of the O-specific polysaccharides of P. vulgaris O23 and P. mirabilis O23 is discussed.

  2. Quantitative Structure Activity Relationship Models for the Antioxidant Activity of Polysaccharides

    PubMed Central

    Nie, Kaiying; Wang, Zhaojing

    2016-01-01

    In this study, quantitative structure activity relationship (QSAR) models for the antioxidant activity of polysaccharides were developed with 50% effective concentration (EC50) as the dependent variable. To establish optimum QSAR models, multiple linear regressions (MLR), support vector machines (SVM) and artificial neural networks (ANN) were used, and 11 molecular descriptors were selected. The optimum QSAR model for predicting EC50 of DPPH-scavenging activity consisted of four major descriptors. MLR model gave EC50 = 0.033Ara-0.041GalA-0.03GlcA-0.025PC+0.484, and MLR fitted the training set with R = 0.807. ANN model gave the improvement of training set (R = 0.96, RMSE = 0.018) and test set (R = 0.933, RMSE = 0.055) which indicated that it was more accurately than SVM and MLR models for predicting the DPPH-scavenging activity of polysaccharides. 67 compounds were used for predicting EC50 of the hydroxyl radicals scavenging activity of polysaccharides. MLR model gave EC50 = 0.12PC+0.083Fuc+0.013Rha-0.02UA+0.372. A comparison of results from models indicated that ANN model (R = 0.944, RMSE = 0.119) was also the best one for predicting the hydroxyl radicals scavenging activity of polysaccharides. MLR and ANN models showed that Ara and GalA appeared critical in determining EC50 of DPPH-scavenging activity, and Fuc, Rha, uronic acid and protein content had a great effect on the hydroxyl radicals scavenging activity of polysaccharides. The antioxidant activity of polysaccharide usually was high in MW range of 4000–100000, and the antioxidant activity could be affected simultaneously by other polysaccharide properties, such as uronic acid and Ara. PMID:27685320

  3. Polysaccharides from Arctium lappa L.: Chemical structure and biological activity.

    PubMed

    Carlotto, Juliane; de Souza, Lauro M; Baggio, Cristiane H; Werner, Maria Fernanda de P; Maria-Ferreira, Daniele; Sassaki, Guilherme L; Iacomini, Marcello; Cipriani, Thales R

    2016-10-01

    The plant Arctium lappa L. is popularly used to relieve symptoms of inflammatory disorders. A crude polysaccharide fraction (SAA) resulting of aqueous extraction of A. lappa leaves showed a dose dependent anti-edematogenic activity on carrageenan-induced paw edema, which persisted for up to 48h. Sequential fractionation by ultrafiltration at 50kDa and 30kDa cut-off membranes yielded three fractions, namely RF50, RF30, and EF30. All these maintained the anti-edematogenic effect, but RF30 showed a more potent action, inhibiting 57% of the paw edema at a dose of 4.9mg/kg. The polysaccharide RF30 contained galacturonic acid, galactose, arabinose, rhamnose, glucose, and mannose in a 7:4:2:1:2:1 ratio and had a Mw of 91,000g/mol. Methylation analysis and NMR spectroscopy indicated that RF30 is mainly constituted by a type I rhamnogalacturonan branched by side chains of types I and II arabinogalactans, and arabinan.

  4. Structural, functional, and antioxidant properties of water-soluble polysaccharides from potatoes peels.

    PubMed

    Jeddou, Khawla Ben; Chaari, Fatma; Maktouf, Sameh; Nouri-Ellouz, Oumèma; Helbert, Claire Boisset; Ghorbel, Raoudha Ellouz

    2016-08-15

    Water-soluble polysaccharides were extracted from potato peel waste (PPW). The structure of the polysaccharides from PPW (PPPW) was examined by means of Fourier transform-infrared spectroscopy (FT-IR) analysis, X-ray diffractometry (XRD) and gas chromatography-mass spectrometry (GC-MS). The results suggest that the extracted polysaccharides form a semi-crystalline polymer constituted essentially of the functional groups CO, CH and OH. Acid hydrolysis of this polymer yielded glucose (76.25%) as the dominant sugar functional properties (water holding capacity: WHC, oil holding capacity: OHC, foaming, and emulsion properties) of this polymer were studied. The PPPW showed interesting water-holding and fat-binding capacities which were 4.097 ± 0.537 g/g and 4.398 ± 0.04 g/g, respectively. In addition, it presented good foaming and emulsion properties. The antioxidant activity of this polymer was also studied and revealed that the polysaccharides showed interesting 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capacity (IC50 PPPW=11.578 mg/mL), reducing power and β-carotene bleaching inhibition activities, and also a strong ABTS radical scavenging activity (IC50 PPPW=2mg/mL). Overall, the results suggest that the polysaccharide is a promising source of natural antioxidants and can be used as additive in food, pharmaceutical and cosmetic preparations.

  5. Bioactive potential and structural chracterization of sulfated polysaccharide from seaweed (Gracilaria corticata).

    PubMed

    Seedevi, Palaniappan; Moovendhan, Meivelu; Viramani, Shanmugam; Shanmugam, Annian

    2017-01-02

    The Sulfated polysaccharide was purified through anion-exchange and gel permeation column chromatography. The isolated sulfated polysaccharide from C. corticata contains 84% of carbohydrate, 0% of protein, 19.7% of ash and 29.4% of moisture was found. The carbon, hydrogen, nitrogen and sulfur content as 33.19%, 5.91%, 7.21% and 3.75%. The molecular weight of sulfated polysaccharide was found to be 43kDa. The sugar was composed of (90.11%), glucose (5.47%), xylose (2.30%) and mannose (2.12%). The structural feature of sulfated polysachharide was studied through FT-IR and (1)H NMR spectral analysis. Further the sulfated polysaccharide showed total antioxidant activity of 24.93%-75.21% at 50-250μg/ml, DPPH free radical scavenging activity of 23.12%-73.01% at 10-160μg/ml, ABTS scavenging activity of 15.8%-74.5% at 25-125μg/ml hydroxyl radical scavenging activity 12.87-69.19% at 25-125μg/ml and superoxide radical scavenging activity 28.10-78.11% at 50-250μg/ml respectively. The sulfated polysaccharide has shown good antibacterial activity against human pathogen.

  6. Polysaccharide components from the scape of Musa paradisiaca: main structural features of water-soluble polysaccharide component.

    PubMed

    Anjaneyalu, Y V; Jagadish, R L; Raju, T S

    1997-06-01

    Polysaccharide components present in the pseudo-stem (scape) of M. paradisiaca were purified from acetone powder of the scape by delignification followed by extraction with aqueous solvents into water soluble polysaccharide (WSP), EDTA-soluble polysaccharide (EDTA-SP), alkali-soluble polysaccharide (ASP) and alkali-insoluble polysaccharide (AISP) fractions. Sugar compositional analysis showed that WSP and EDTA-SP contained only D-Glc whereas ASP contained D-Glc, L-Ara and D-Xyl in approximately 1:1:10 ratio, respectively, and AISP contained D-Glc, L-Ara and D-Xyl in approximately 10:1:2 ratio, respectively. WSP was further purified by complexation with iso-amylalcohol and characterized by specific rotation, IR spectroscopy, Iodine affinity, ferricyanide number, blue value, hydrolysis with alpha-amylase and glucoamylase, and methylation linkage analysis, and shown to be a amylopectin type alpha-D-glucan.

  7. Structure of the O-polysaccharide of Providencia stuartii O49.

    PubMed

    Bushmarinov, Ivan S; Ovchinnikova, Olga G; Kocharova, Nina A; Blaszczyk, Aleksandra; Toukach, Filipp V; Torzewska, Agnieszka; Shashkov, Alexander S; Knirel, Yuriy A; Rozalski, Antoni

    2004-06-01

    The O-specific polysaccharide chain (O-antigen) of the lipopolysaccharide (LPS) of Providencia stuartii O49 was studied using sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including two-dimensional COSY, TOCSY, ROESY, H-detected 1H, 13C HSQC and HMBC experiments. The polysaccharide was found to have the trisaccharide repeating unit with the following structure: -->6)-beta-D-Galp(1-->3)-beta-D-GalpNAc(1-->4)-alpha-D-Galp(1-->

  8. Structural characterization and antioxidant activities of polysaccharides extracted from the pulp of Elaeagnus angustifolia L.

    PubMed

    Chen, Qingqing; Chen, Juncheng; Du, Hongtao; Li, Qi; Chen, Jun; Zhang, Gechao; Liu, Hong; Wang, Junru

    2014-06-26

    In this study, two polysaccharides (Elaeagnus angustifolia L. polysaccharide-1 (PEA-1) and PEA-2) were prepared from Elaeagnus angustifolia L. Then, the preliminary structure and antioxidant activities of all the samples were investigated. The results showed that the average molecular weights for PEA-1 and PEA-2 were 9113 and 5020 Da, respectively. And, PEA-1 was mainly composed of rhamnose, xylose, mannose, glucose, and galactose, respectively. The components of PEA-2 were rhamnose, mannose, glucose, and galactose, respectively. Moreover, the Antioxidant assays demonstrated that PEA-1 possessed of strong free radicals scavenging activity and hydroxyl radicals scavenging activities, suggesting that PEA-1 could potentially be used as natural antioxidant.

  9. Structural Characterization and Antioxidant Activities of Polysaccharides Extracted from the Pulp of Elaeagnus angustifolia L.

    PubMed Central

    Chen, Qingqing; Chen, Juncheng; Du, Hongtao; Li, Qi; Chen, Jun; Zhang, Gechao; Liu, Hong; Wang, Junru

    2014-01-01

    In this study, two polysaccharides (Elaeagnus angustifolia L. polysaccharide-1 (PEA-1) and PEA-2) were prepared from Elaeagnus angustifolia L. Then, the preliminary structure and antioxidant activities of all the samples were investigated. The results showed that the average molecular weights for PEA-1 and PEA-2 were 9113 and 5020 Da, respectively. And, PEA-1 was mainly composed of rhamnose, xylose, mannose, glucose, and galactose, respectively. The components of PEA-2 were rhamnose, mannose, glucose, and galactose, respectively. Moreover, the Antioxidant assays demonstrated that PEA-1 possessed of strong free radicals scavenging activity and hydroxyl radicals scavenging activities, suggesting that PEA-1 could potentially be used as natural antioxidant. PMID:24972139

  10. Structural studies of the serotype-f polysaccharide antigen from Streptococcus mutans OMZ175.

    PubMed Central

    Linzer, R; Reddy, M S; Levine, M J

    1987-01-01

    The serotype f antigen of Streptococcus mutans has been described as a rhamnose-glucose polysaccharide associated with the bacterial cell wall. In this study, the structure of serotype f polysaccharide was examined by analyses of the methylated derivatives of the antigen and the periodate-oxidized antigen. Methylated derivatives were characterized with a gas chromatograph-mass spectrometer. The polysaccharide appeared to have a backbone of alternating 1,3- and 1,2,3-linked rhamnose units. Branching occurred at the 3-position of the 1,2,3-linked rhamnose. Side chains were composed of terminal alpha-linked glucose units. A small proportion of longer side chains containing 1,2- and 1,6-linked glucose units were noted in some preparations; however, these determinants were not reactive with serotype f antisera. PMID:2824381

  11. Structure of a glucosyl phosphate-containing O-polysaccharide of Proteus vulgaris O42.

    PubMed

    Perepelov, Andrei V; Bartodziejska, Beata; Shashkov, Alexander S; Wykrota, Marianna; Knirel, Yuriy A; Rozalski, Antoni

    2007-12-28

    An O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of Proteus vulgaris O42 and studied by sugar and methylation analyses along with 1H, 13C and 31P NMR spectroscopy. The following structure of the polysaccharide having a linear pentasaccharide phosphate repeating unit was established: -->3)-alpha-L-FucpNAc4Ac-(1-->4)-alpha-D-Glcp-1-P-(O-->4)-alpha-D-GlcpNAc-(1-->3)-alpha-L-FucpNAc4Ac-(1-->3))-alpha-D-GlcpNAc6Ac-(1--> where the degree of O-acetylation is approximately 80% on GlcNAc and approximately 40% on each of the FucNAc residues. A weak serological cross-reaction of anti-P. vulgaris O42 serum with the lipopolysaccharide of P. vulgaris O39 was observed and accounted for by the sharing of a disaccharide fragment of the O-polysaccharides.

  12. Evolution of the capsular operon of Streptococcus iniae in response to vaccination.

    PubMed

    Millard, Candice M; Baiano, Justice C F; Chan, Candy; Yuen, Benedict; Aviles, Fabian; Landos, Matt; Chong, Roger S M; Benedict, Suresh; Barnes, Andrew C

    2012-12-01

    Streptococcus iniae causes severe septicemia and meningitis in farmed fish and is also occasionally zoonotic. Vaccination against S. iniae is problematic, with frequent breakdown of protection in vaccinated fish. The major protective antigens in S. iniae are the polysaccharides of the capsule, which are essential for virulence. Capsular biosynthesis is driven and regulated by a 21-kb operon comprising up to 20 genes. In a long-term study, we have sequenced the capsular operon of strains that have been used in autogenous vaccines across Australia and compared it with the capsular operon sequences of strains subsequently isolated from infected vaccinated fish. Intriguingly, strains isolated from vaccinated fish that subsequently become infected have coding mutations that are confined to a limited number of genes in the cps operon, with the remainder of the genes in the operon remaining stable. Mutations in strains in diseased vaccinated fish occur in key genes in the capsular operon that are associated with polysaccharide configuration (cpsG) and with regulation of biosynthesis (cpsD and cpsE). This, along with high ratios of nonsynonymous to synonymous mutations within the cps genes, suggests that immune response directed predominantly against capsular polysaccharide may be driving evolution in a very specific set of genes in the operon. From these data, it may be possible to design a simple polyvalent vaccine with a greater operational life span than the current monovalent killed bacterins.

  13. Evolution of the Capsular Operon of Streptococcus iniae in Response to Vaccination

    PubMed Central

    Millard, Candice M.; Baiano, Justice C. F.; Chan, Candy; Yuen, Benedict; Aviles, Fabian; Landos, Matt; Chong, Roger S. M.; Benedict, Suresh

    2012-01-01

    Streptococcus iniae causes severe septicemia and meningitis in farmed fish and is also occasionally zoonotic. Vaccination against S. iniae is problematic, with frequent breakdown of protection in vaccinated fish. The major protective antigens in S. iniae are the polysaccharides of the capsule, which are essential for virulence. Capsular biosynthesis is driven and regulated by a 21-kb operon comprising up to 20 genes. In a long-term study, we have sequenced the capsular operon of strains that have been used in autogenous vaccines across Australia and compared it with the capsular operon sequences of strains subsequently isolated from infected vaccinated fish. Intriguingly, strains isolated from vaccinated fish that subsequently become infected have coding mutations that are confined to a limited number of genes in the cps operon, with the remainder of the genes in the operon remaining stable. Mutations in strains in diseased vaccinated fish occur in key genes in the capsular operon that are associated with polysaccharide configuration (cpsG) and with regulation of biosynthesis (cpsD and cpsE). This, along with high ratios of nonsynonymous to synonymous mutations within the cps genes, suggests that immune response directed predominantly against capsular polysaccharide may be driving evolution in a very specific set of genes in the operon. From these data, it may be possible to design a simple polyvalent vaccine with a greater operational life span than the current monovalent killed bacterins. PMID:23001668

  14. Structure of the O-specific polysaccharide of Proteus vulgaris O4 containing a new component of bacterial polysaccharides, 4,6-dideoxy-4.

    PubMed

    Perepelov, A V; Babicka, D; Senchenkova, S N; Shashkov, A S; Moll, H; Rozalski, A; Zähringer, U; Knirel, Y A

    2001-03-22

    A high-molecular-mass O-specific polysaccharide was obtained by mild acid degradation of Proteus vulgaris O4 lipopolysaccharide followed by GPC. The polysaccharide was studied by chemical methods along with 1H and 13C NMR spectroscopy, including two-dimensional COSY, TOCSY, NOESY, H-detected 1H,13C HMQC, and 1H,13C HMBC experiments. Solvolysis of the polysaccharide with trifluoromethanesulfonic (triflic) acid resulted in a GlcpA-(1 --> 3)-GlcNAc disaccharide and a novel amino sugar derivative, 4,6-dideoxy-4-[N-[(R)-3-hydroxybutyryl]-L-alanyl]amino-D-glucose [Qui4N(HbAla)]. On the basis of the data obtained, the following structure of the tetrasaccharide repeating unit of the O-specific polysaccharide was established: --> 4)-beta-D-GlcpA-(1 --> 3)-beta-D-GlcpNAc-(1 --> 2)-beta-D-Quip4N(HbAla)-(1 --> 3)-alpha-D-Galp-(1 -->. This structure is unique among the O-specific polysaccharides, which is in accordance with classification of the strain studied in a separate Proteus serogroup.

  15. Structural studies on the fucosamine-containing O-specific polysaccharide of Proteus vulgaris O19.

    PubMed

    Vinogradov, E V; Kaca, W; Knirel, Y A; Rózalski, A; Kochetkov, N K

    1989-03-01

    The polysaccharide chain of Proteus vulgaris O19 lipopolysaccharide contains D-galactose, N-acetyl-D-glucosamine N-acetyl-D-galactosamine and N-acetyl-L-fucosamine in the ratio 1:1:1:1. The structure of the polysaccharide was established by full acid hydrolysis and methylation analysis, as well as by non-destructive methods, i.e. the computer-assisted evaluation of the 13C-NMR spectrum and computer-assisted evaluation of the specific optical rotation by Klyne's rule. The polysaccharide is regular and built up of tetrasaccharide repeating units of the following structure: ----3)-alpha-L-FucNAcp-(1----3)-beta-D-GlcNAcp-(1----3)-alph a-D-Galp- (1----4)-alpha-D-GalNAcp-(1---- The O19-antiserum cross-reacts with lipopolysaccharide from P. vulgaris O42, the structure of which is still unknown. No cross-reactions were observed with O-polysaccharides Pseudomonas aeruginosa O7 and Salmonella arizonae O59 in spite of some structural similarities.

  16. Polysaccharide intercellular adhesin in biofilm: structural and regulatory aspects

    PubMed Central

    Arciola, Carla Renata; Campoccia, Davide; Ravaioli, Stefano; Montanaro, Lucio

    2015-01-01

    Staphylococcus aureus and Staphylococcus epidermidis are the leading etiologic agents of implant-related infections. Biofilm formation is the main pathogenetic mechanism leading to the chronicity and irreducibility of infections. The extracellular polymeric substances of staphylococcal biofilms are the polysaccharide intercellular adhesin (PIA), extracellular-DNA, proteins, and amyloid fibrils. PIA is a poly-β(1-6)-N-acetylglucosamine (PNAG), partially deacetylated, positively charged, whose synthesis is mediated by the icaADBC locus. DNA sequences homologous to ica locus are present in many coagulase-negative staphylococcal species, among which S. lugdunensis, however, produces a biofilm prevalently consisting of proteins. The product of icaA is an N-acetylglucosaminyltransferase that synthetizes PIA oligomers from UDP-N-acetylglucosamine. The product of icaD gives optimal efficiency to IcaA. The product of icaC is involved in the externalization of the nascent polysaccharide. The product of icaB is an N-deacetylase responsible for the partial deacetylation of PIA. The expression of ica locus is affected by environmental conditions. In S. aureus and S. epidermidis ica-independent alternative mechanisms of biofilm production have been described. S. epidermidis and S. aureus undergo to a phase variation for the biofilm production that has been ascribed, in turn, to the transposition of an insertion sequence in the icaC gene or to the expansion/contraction of a tandem repeat naturally harbored within icaC. A role is played by the quorum sensing system, which negatively regulates biofilm formation, favoring the dispersal phase that disseminates bacteria to new infection sites. Interfering with the QS system is a much debated strategy to combat biofilm-related infections. In the search of vaccines against staphylococcal infections deacetylated PNAG retained on the surface of S. aureus favors opsonophagocytosis and is a potential candidate for immune-protection. PMID

  17. Structural diversity requires individual optimization of ethanol concentration in polysaccharide precipitation.

    PubMed

    Xu, Jun; Yue, Rui-Qi; Liu, Jing; Ho, Hing-Man; Yi, Tao; Chen, Hu-Biao; Han, Quan-Bin

    2014-06-01

    Ethanol precipitation is one of the most widely used methods for preparing natural polysaccharides, in which ethanol concentration significantly affects the precipitate yield, however, is usually set at 70-80%. Whether the standardization of ethanol concentration is appropriate has not been investigated. In the present study, the precipitation yields produced in varied ethanol concentrations (10-90%) were qualitatively and quantitatively evaluated by HPGPC (high-performance gel-permeation chromatography), using two series of standard glucans, namely dextrans and pullulans, as reference samples, and then eight natural samples. The results indicated that the response of a polysaccharide's chemical structure, with diversity in structural features and molecular sizes, to ethanol concentration is the decisive factor in precipitation of these glucans. Polysaccharides with different structural features, even though they have similar molecular weights, exhibit significantly different precipitation behaviors. For a specific glucan, the lower its molecular size, the higher the ethanol concentration needed for complete precipitation. The precipitate yield varied from 10% to 100% in 80% ethanol as the molecular size increased from 1kDa to 270kDa. This paper aims to draw scientists' attention to the fact that, in extracting natural polysaccharides by ethanol precipitation, the ethanol concentration must be individually optimized for each type of material.

  18. Structural properties of polysaccharides from cultivated fruit bodies and mycelium of Cordyceps militaris.

    PubMed

    Liu, Xiao-Cui; Zhu, Zhen-Yuan; Tang, Ya-Li; Wang, Ming-fei; Wang, Zheng; Liu, An-Jun; Zhang, Yong-Min

    2016-05-20

    The structural properties of polysaccharides, respectively, obtained from the fermented mycelium and cultivated fruiting bodies of the Cordyceps militaris were investigated and compared in this paper. First, the crude polysaccharides were extracted from the mycelium and the fruiting bodies, respectively. The polysaccharides were successively purified by Sevag and chromatography on Sephadex G-100 column to produce two polysaccharides fractions termed CMPS-II and CBPS-II, respectively. The average molecular weights of CMPS-II and CBPS-II were 1.402×10(3) kDa and 1.273×10(3) kDa, respectively, and they were mainly composed of mannose, glucose and galactose in the mole ratios of 1:28.63:1.41 and 1:12.41:0.74, respectively, for CMPS-II and CBPS-II. Afterward, the structural features of CMPS-II and CBPS-II were investigated by a combination of chemical and instrumental analysis, such as FT-IR, periodate oxidation-Smith degradation, GC-MS, NMR and methylation analysis. The results indicated that structurally, both CMPS-II and CBPS-II were 1,3-branched-galactomannoglucan that had a linear backbone of (1→4)-linked α-D-glucopyranose (Glcp). Congo-red test revealed that CMPS-II and CBPS-II existed as triple-helical chains in 0.05-0.15 M NaOH solution.

  19. Identification of a capsular variant and characterization of capsular acetylation in Klebsiella pneumoniae PLA-associated type K57

    PubMed Central

    Hsu, Chun-Ru; Liao, Chun-Hsing; Lin, Tzu-Lung; Yang, Han-Ru; Yang, Feng-Ling; Hsieh, Pei-Fang; Wu, Shih-Hsiung; Wang, Jin-Town

    2016-01-01

    Klebsiella pneumoniae can cause community-acquired pyogenic liver abscess (PLA). Capsular polysaccharide (CPS) is important for its virulence. Among 79 capsular (K) types discovered thus far, K57 is often associated with PLA. Here, we report the identification of a K57 variant. Cps gene locus sequencing revealed differences between the K57 reference strain 4425/51 (Ref-K57) and a variant, the PLA isolate A1142. While Ref-K57 cps contained orf13 encoding a putative acetyltransferase, the insertion of a putative transposase-encoding gene at this position was detected in A1142. This variation was detected in other K57 clinical strains. Biochemical analyses indicated that A1142 was deficient in CPS acetylation. Genetic replacement and complementation verified that orf13 was responsible for CPS acetylation. Acetylation increased CPS immunoreactivity to antiserum and enhanced K. pneumoniae induction of pro-inflammatory cytokines through JNK and MAPK signaling. While acetylation diminished the serum resistance of bacteria, it promoted adhesion to intestinal epithelial cells possibly via increasing production of type I fimbriae. In conclusion, acetylation-mediated capsular variation in K57 was observed. Capsular acetylation contributed to the variety and antigenic diversity of CPS, influenced its biological activities, and was involved in K. pneumoniae-host interactions. These findings have implications for vaccine design and pathogenicity of K. pneumoniae. PMID:27550826

  20. Polysaccharides of St. John's Wort Herb Stimulate NHDF Proliferation and NEHK Differentiation via Influence on Extracellular Structures and Signal Pathways.

    PubMed

    Abakuks, S; Deters, A M

    2012-01-01

    St. John's Wort herb extracts often contain undesirable or volitional polysaccharides. As polysaccharides exhibit structure-dependent biological functions in the present study water-soluble polysaccharides were extracted from herb material, fractionated by anion exchange chromatography into four main polysaccharide fractions (denominated as Hp1, Hp2, Hp3 and Hp4) and characterized by HPAEC-PAD, CE, IR and GC-MS. Biological activity on human skin keratinocytes and fibroblasts was assessed by investigation of their effect on proliferation, metabolism, cytotoxicity, apoptosis and differentiation. The underlying mechanisms were investigated in gene expression studies. Polysaccharide fraction Hp1 was mainly composed of β-D-glucose. Hp2, Hp3 and Hp4 contained pectic structures and arabinogalactan proteins varying in composition and quantity. Polysaccharides of Hp1 induced the keratinocyte differentiation by inhibiting the gene expression of the epidermal growth factor and insulin receptor. While the collagen secretion of fibroblasts was stimulated by each polysaccharide fraction only Hp1 stimulated the synthesis. The fibroblast proliferation was reduced by Hp1 and increased by Hp4. This effect was related to the influence on genes that referred to oxidative stress, metabolism, transcription processes and extracellular proteins. In conclusion polysaccharides have been shown as biologically active ingredients of aqueous St. John's Wort extracts with a relation between their structural characteristics and function.

  1. Polysaccharides of St. John's Wort Herb Stimulate NHDF Proliferation and NEHK Differentiation via Influence on Extracellular Structures and Signal Pathways

    PubMed Central

    Abakuks, S.; Deters, A. M.

    2012-01-01

    St. John's Wort herb extracts often contain undesirable or volitional polysaccharides. As polysaccharides exhibit structure-dependent biological functions in the present study water-soluble polysaccharides were extracted from herb material, fractionated by anion exchange chromatography into four main polysaccharide fractions (denominated as Hp1, Hp2, Hp3 and Hp4) and characterized by HPAEC-PAD, CE, IR and GC-MS. Biological activity on human skin keratinocytes and fibroblasts was assessed by investigation of their effect on proliferation, metabolism, cytotoxicity, apoptosis and differentiation. The underlying mechanisms were investigated in gene expression studies. Polysaccharide fraction Hp1 was mainly composed of β-D-glucose. Hp2, Hp3 and Hp4 contained pectic structures and arabinogalactan proteins varying in composition and quantity. Polysaccharides of Hp1 induced the keratinocyte differentiation by inhibiting the gene expression of the epidermal growth factor and insulin receptor. While the collagen secretion of fibroblasts was stimulated by each polysaccharide fraction only Hp1 stimulated the synthesis. The fibroblast proliferation was reduced by Hp1 and increased by Hp4. This effect was related to the influence on genes that referred to oxidative stress, metabolism, transcription processes and extracellular proteins. In conclusion polysaccharides have been shown as biologically active ingredients of aqueous St. John's Wort extracts with a relation between their structural characteristics and function. PMID:22848211

  2. Structural features of an immunostimulating and antioxidant acidic polysaccharide from the seeds of Cuscuta chinensis.

    PubMed

    Bao, Xingfeng; Wang, Zhan; Fang, Jinian; Li, Xiaoyu

    2002-03-01

    Three crude polysaccharide fractions, named CS-A, CS-B and CS-C, were prepared from the seeds of Cuscuta chinensis by hot water extraction and diluted alkali extraction subsequently, then EtOH precipitation, and tested for lymphocyte proliferation activity. CS-A showed a stimulating effect on concanavalin A or lipopolysaccharide induced mitogenic activity of lymphocytes. An acidic polysaccharide (CS-A-3beta) was purified from CS-A by anion exchange and gel filtration chromatography. The polysaccharide showed potent stimulating effects on lymphocyte proliferation and antibody production, but did not significantly influence the serum IgG level. Its structural features were elucidated by methylation analysis, partial acid hydrolysis, 1D and 2D NMR and ESI-mass spectroscopy. The data obtained indicated that CS-A-3beta had a backbone consisting of alpha-D-1,4-linked GalpA residues and beta-L-1,2-linked Rhap residues with branches at C-4 of Rhap residues and C-3 of GalpA residues, composed of arabinogalactan and glucobiose. This structure is typical for a pectic polysaccharide of the rhamnogalacturonan type. In addition, the effect of CS-A, CS-B, CS-C and CS-A-3beta on hydrogen peroxide induced cell lesion in rat pheochromocytoma line PC 12 was investigated. The results indicated that, besides its immunostimulating activity, CS-A-3beta had a protective effect against free radical-induced cell toxicity.

  3. Structural Characterisation of a Polysaccharide from Radix Ranunculus Ternati

    PubMed Central

    Huang, Xuefeng; Zhao, Yun; Jin, Xin

    2014-01-01

    A water soluble polysaccharide, HB-1, with a molecular weight of 23,930, was isolated from radix Ranunculi ternati. by hot water extraction, ethanol precipitation, deproteination,ultrafiltration and gel-filtration column chromatography. Its sugar composition was determined by GLC as Glc, Ara, and Gal in a molar ration of 16.071: 2.722: 1. And the absolute configuration of Glc was identified as D. Smith degradation and methylation reaction showed the proportion of —1Glc (A) was about 16%, —1Glc4— (B) about 62%, (C) about 14%, and —1Gal6— (D) about 8%. The repetitive unit was likely composed of 3 As, 3 Cs, 13 Bs and 1 D. Together with the average molecular weight, it was predictable that HB-1 consisted of about seven of the repetitive unit. The inhibition activity of HB-1 on human glioma cell line SF188 was also measured, only to find it inactive. PMID:25587330

  4. Study on molecular structural characteristics of tea polysaccharide.

    PubMed

    Guo, Li; Du, Xianfeng; Lan, Jing; Liang, Qin

    2010-08-01

    Tea polysaccharide (TPS) is attracting more attention gradually due to its particular biological properties. However, molecular characteristics of TPS are unclear since appropriate method is still absent. So, study on the molecular characteristics of TPS was carried out by high-performance size-exclusion chromatography (HPSEC), multi-angle laser light scattering (MALLS) and viscosimetry. The results showed that the molar masses of TPS ranged from 2.287 x 10(5) to 2.762 x 10(5)gmol(-1), the RMS radii distributed from 132.1 to 145.9 nm, and M(w)/M(n) is 1.028. The Mark-Houwink equation was established as [eta]=0.5423 M(w)(0.5379), and the intrinsic viscosity and molecular chain parameters were as follows: [eta]=1.007 dL g(-1), k(H)=0.845, k(K)=0.387, alpha=0.5379, K=0.5423. In addition, based on the slope of the RMS radius versus molar mass conformational plot being 0.24+/-0.00, we suggest that the molecular morphology of TPS is a homogeneous and spherical polymer with branch in solution.

  5. Anti-cancer effect and structural characterization of endo-polysaccharide from cultivated mycelia of Inonotus obliquus.

    PubMed

    Kim, Yong Ook; Park, Hae Woong; Kim, Jong Hoon; Lee, Jae Young; Moon, Seong Hoon; Shin, Chul Soo

    2006-05-30

    The endo-polysaccharide extracted from mycelia of Inonotus obliquus (Pers.:Fr.) Pil. (Hymenochaetaceae) is a specific activator of B cells and macrophages. However, the in vivo anti-cancer effects and the chemical structure of the endo-polysaccharide are unknown. We purified the endo-polysaccharide, investigated its anti-cancer effects via in vitro and in vivo assays, and performed a structural characterization. The endo-polysaccharide was extracted from I. obliquus mycelia cultivated in a 300-l pilot fermenter, followed by hot water extraction and ethanol precipitation. Purification was achieved by DEAE-cellulose ion-exchange chromatography and gel-permeation chromatography. Chemical analysis revealed that the purified endo-polysaccharide is an alpha-linked fucoglucomannan with a molecular weight of approximately 1,000 kDa. The anti-cancer activities of the endo-polysaccharide against various types of tumor cells were determined. No direct toxicity against either cancer or normal cells was observed. Intraperitoneal administration of the endo-polysaccharide significantly prolonged the survival rate of B16F10-implanted mice, resulting in a 4.07-fold increase in the survival rate at a dose of 30 mg/kg/day. After 60 days of feeding, approximately 67% of the initial number of mice survived with no tumor incidence based on macroscopic examination. These results indicate that the anti-cancer effect of endo-polysaccharide is not directly tumorcidal but rather is immuno-stimulating.

  6. Synthesis, Structural, and Adsorption Properties and Thermal Stability of Nanohydroxyapatite/Polysaccharide Composites.

    PubMed

    Skwarek, Ewa; Goncharuk, Olena; Sternik, Dariusz; Janusz, Wladyslaw; Gdula, Karolina; Gun'ko, Vladimir M

    2017-12-01

    A series of composites based on nanohydroxyapatite (nHAp) and natural polysaccharides (PS) (nHAp/agar, nHAp/chitosan, nHAp/pectin FB300, nHAp/pectin APA103, nHAp/sodium alginate) was synthesized by liquid-phase two-step method and characterized using nitrogen adsorption-desorption, DSC, TG, FTIR spectroscopy, and SEM. The analysis of nitrogen adsorption-desorption data shows that composites with a nHAp: PS ratio of 4:1 exhibit a sufficiently high specific surface area from 49 to 82 m(2)/g. The incremental pore size distributions indicate mainly mesoporosity. The composites with the component ratio 1:1 preferably form a film-like structure, and the value of S BET varies from 0.3 to 43 m(2)/g depending on the nature of a polysaccharide. Adsorption of Sr(II) on the composites from the aqueous solutions has been studied. The thermal properties of polysaccharides alone and in nHAp/PS show the influence of nHAp, since there is a shift of characteristic DSC and DTG peaks. FTIR spectroscopy data confirm the presence of functional groups typical for nHAp as well as polysaccharides in composites. Structure and morphological characteristics of the composites are strongly dependent on the ratio of components, since nHAp/PS at 4:1 have relatively large S BET values and a good ability to adsorb metal ions. The comparison of the adsorption capacity with respect to Sr(II) of nHAp, polysaccharides, and composites shows that it of the latter is higher than that of nHAp (per 1 m(2) of surface).

  7. Synthesis, Structural, and Adsorption Properties and Thermal Stability of Nanohydroxyapatite/Polysaccharide Composites

    NASA Astrophysics Data System (ADS)

    Skwarek, Ewa; Goncharuk, Olena; Sternik, Dariusz; Janusz, Wladyslaw; Gdula, Karolina; Gun'ko, Vladimir M.

    2017-02-01

    A series of composites based on nanohydroxyapatite (nHAp) and natural polysaccharides (PS) (nHAp/agar, nHAp/chitosan, nHAp/pectin FB300, nHAp/pectin APA103, nHAp/sodium alginate) was synthesized by liquid-phase two-step method and characterized using nitrogen adsorption-desorption, DSC, TG, FTIR spectroscopy, and SEM. The analysis of nitrogen adsorption-desorption data shows that composites with a nHAp: PS ratio of 4:1 exhibit a sufficiently high specific surface area from 49 to 82 m2/g. The incremental pore size distributions indicate mainly mesoporosity. The composites with the component ratio 1:1 preferably form a film-like structure, and the value of S BET varies from 0.3 to 43 m2/g depending on the nature of a polysaccharide. Adsorption of Sr(II) on the composites from the aqueous solutions has been studied. The thermal properties of polysaccharides alone and in nHAp/PS show the influence of nHAp, since there is a shift of characteristic DSC and DTG peaks. FTIR spectroscopy data confirm the presence of functional groups typical for nHAp as well as polysaccharides in composites. Structure and morphological characteristics of the composites are strongly dependent on the ratio of components, since nHAp/PS at 4:1 have relatively large S BET values and a good ability to adsorb metal ions. The comparison of the adsorption capacity with respect to Sr(II) of nHAp, polysaccharides, and composites shows that it of the latter is higher than that of nHAp (per 1 m2 of surface).

  8. Structural and immunological feature of rhamnogalacturonan I-rich polysaccharide from Korean persimmon vinegar.

    PubMed

    Kim, Hoon; Hong, Hee-Do; Suh, Hyung-Joo; Shin, Kwang-Soon

    2016-08-01

    The crude polysaccharide (KPV-0) isolated from Korean persimmon vinegar was fractionated using gel filtration chromatography to enhance the immunostimulatory activity and to identify the structural features of active fraction. Among three fractions, KPV-I obtained in a void volume, demonstrated the potent production of macrophage-stimulating mediators, including tumor necrosis factor-α, interleukin (IL)-6, IL-12, and nitric oxide. KPV-I showed a combined single peak with high molecular weight of 55,000Da by high performance size exclusion chromatography. Component sugar analysis revealed that KPV-I contained mainly of arabinose, mannose, galactose, rhamnose and galacturonic acid. Single radial gel diffusion assay using β-glucosyl Yariv reagent showed that KPV-I contained arabinogalactan protein with 13.7%. Methylation analysis indicated that KPV-I contained 21 kinds of neutral glycosidic linkages, which seemed to be composed three kinds of polysaccharide; that is a rhamnogalacturonan-I (65-70%) derived from persimmon as a raw material, a mannan (20-25%) derived from fermentation-associated microorganisms, and a linear glucans (less than 10%). In conclusion, polysaccharide isolated from persimmon vinegar could augment the macrophage stimulation, and a large amounts of RG-I polysaccharide derived from persimmon is likely a crucial role in expression of the activity in persimmon vinegar.

  9. Structural characterization, sulfation and antitumor activity of a polysaccharide fraction from Cyclina sinensis.

    PubMed

    Jiang, Changxing; Xiong, Qingping; Li, Songlin; Zhao, Xirong; Zeng, Xiaoxiong

    2015-01-22

    In the present study, we investigated the preliminary structure, sulfation and antitumor activity of a polysaccharide fraction from Cyclina sinensis (CSPS-1). Results of structural characterization showed that the backbone chain of CSPS-1 was composed of glucose linked by α-(1→4) glycosidic bond, and the branch chain was attached to backbone chain by (1→6) glycosidic bond. CSPS-1 was sulfated by chlorosulfonic acid-pyridine method under different modification conditions according to the orthogonal test L9(3(4)), affording nine sulfated polysaccharides (CSPS-1-S). The optimal sulfation conditions for CSPS-1 were reaction temperature of 65°C, reaction time of 2h and chlorosulfonic acid-pyridine ratio of 1:4. Structural analysis revealed that sulfation had occurred at position of C-6 in CSPS-1. In addition, CSPS-1-S exhibited significantly higher inhibitory activity in vitro against human gastric cancer BGC-823 cells.

  10. Structure of the β-l-fucopyranosyl phosphate-containing O-specific polysaccharide of Escherichia coli O84.

    PubMed

    Knirel, Yuriy A; Qian, Chengqian; Senchenkova, Sofya N; Guo, Xi; Shashkov, Alexander S; Chizhov, Alexander O; Perepelov, Andrei V; Liu, Bin

    2016-07-01

    Fine structure of the O-polysaccharide chain of the lipopolysaccharide (O-antigen) defines the serospecificity of bacterial cells, which is the basis for O-serotyping of medically and agriculturally important gram-negative bacteria including Escherichia coli. In order to obtain the O-polysaccharide for structural analysis, the lipopolysaccharide was isolated from cells of E. coli O84a by phenol/water extraction and degraded with mild acid. However, the O-polysaccharide was cleaved at a highly acid-labile β-l-fucopyranosyl phosphate (β-l-Fucp-1-P) linkage to give mainly a pentasaccharide that corresponded to the O-polysaccharide repeat. Therefore, the lipopolysaccharide and the pentasaccharide as well as their O-deacylated derivatives were studied using sugar analysis, NMR spectroscopy, and (for oligosaccharides) ESI HR MS, and the O84-polysaccharide structure was established. The O-polysaccharide is distinguished by the presence of β-l-Fucp-1-P and randomly di-O-acetylated 6-deoxy-d-talose, which are found for the first time in natural carbohydrates. The gene cluster for the O84-antigen biosynthesis was analysed and its content was found to be consistent with the O-polysaccharide structure.

  11. The structure of sulfated polysaccharides ensures a carbohydrate-based mechanism for species recognition during sea urchin fertilization.

    PubMed

    Vilela-Silva, Ana-Cristina E S; Hirohashi, Noritaka; Mourão, Paulo A S

    2008-01-01

    The evolution of barriers to inter-specific hybridization is a crucial step in the fertilization of free spawning marine invertebrates. In sea urchins, molecular recognition between sperm and egg ensures species recognition. Here we review the sulfated polysaccharide-based mechanism of sperm-egg recognition in this model organism. The jelly surrounding sea urchin eggs is not a simple accessory structure; it is molecularly complex and intimately involved in gamete recognition. It contains sulfated polysaccharides, sialoglycans and peptides. The sulfated polysaccharides have unique structures, composed of repetitive units of alpha-L-fucose or alpha-L-galactose, which differ among species in the sulfation pattern and/or the position of the glycosidic linkage. The egg jelly sulfated polysaccharides show species-specificity in inducing the sperm acrosome reaction, which is regulated by the structure of the saccharide chain and its sulfation pattern. Other components of the egg jelly do not possess acrosome reaction inducing activity, but sialoglycans act in synergy with the sulfated polysaccharide, potentiating its activity. The system we describe establishes a new view of cell-cell interaction in the sea urchin model system. Here, structural changes in egg jelly polysaccharides modulate cell-cell recognition and species-specificity leading to exocytosis of the acrosome. Therefore, sulfated polysaccharides, in addition to their known functions as growth factors, coagulation factors and selectin binding partners, also function in fertilization. The differentiation of these molecules may play a role in sea urchin speciation.

  12. Campylobacter jejuni capsular genotypes are related to Guillain-Barré syndrome.

    PubMed

    Heikema, A P; Islam, Z; Horst-Kreft, D; Huizinga, R; Jacobs, B C; Wagenaar, J A; Poly, F; Guerry, P; van Belkum, A; Parker, C T; Endtz, H P

    2015-09-01

    In about one in a thousand cases, a Campylobacter jejuni infection results in the severe polyneuropathy Guillain-Barré syndrome (GBS). It is established that sialylated lipo-oligosaccharides (LOS) of C. jejuni are a crucial virulence factor in GBS development. Frequent detection of C. jejuni with sialylated LOS in stools derived from patients with uncomplicated enteritis implies that additional bacterial factors should be involved. To assess whether the polysaccharide capsule is a marker for GBS, the capsular genotypes of two geographically distinct GBS-associated C. jejuni strain collections and an uncomplicated enteritis control collection were determined. Capsular genotyping of C. jejuni strains from the Netherlands revealed that three capsular genotypes, HS1/44c, HS2 and HS4c, were dominant in GBS-associated strains and capsular types HS1/44c and HS4c were significantly associated with GBS (p 0.05 and p 0.01, respectively) when compared with uncomplicated enteritis. In a GBS-associated strain collection from Bangladesh, capsular types HS23/36c, HS19 and HS41 were most prevalent and the capsular types HS19 and HS41 were associated with GBS (p 0.008 and p 0.02, respectively). Next, specific combinations of the LOS class and capsular genotypes were identified that were related to the occurrence of GBS. Multilocus sequence typing revealed restricted genetic diversity for strain populations with the capsular types HS2, HS19 and HS41. We conclude that capsular types HS1/44c, HS2, HS4c, HS19, HS23/36c and HS41 are markers for GBS. Besides a crucial role for sialylated LOS of C. jejuni in GBS pathogenesis, the identified capsules may contribute to GBS susceptibility.

  13. Sulfation effect on levan polysaccharide chains structure with molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Coskunkan, Binnaz; Turgut, Deniz; Rende, Deniz; Malta, Seyda; Baysal, Nihat; Ozisik, Rahmi; Toksoy-Oner, Ebru

    Diversity in conformations and structural heterogeneity make polysaccharides the most challenging biopolymer type for experimental and theoretical characterization studies. Levan is a biopolymer chain that consists of fructose rings with β(2-6) linkages. It is a glycan that has great potential as a functional biopolymer in foods, feeds, cosmetics, pharmaceutical and chemical industries. Sulfated polysaccharides are group of macromolecules with sulfated groups in their hydroxyl parts with a range of important biological properties. Sulfate groups and their positions have a major effect on anticoagulant activity. It is reported that sulfate modified levan has anticoagulant activity such as heparin. In the current study, the effect of sulfation on the structure and dynamics of unmodified and sulfate modified levan are investigated via fully atomistic Molecular Dynamics simulations in aqueous media and varying salt concentrations at 310 K. This material is based upon work supported by the National Science Foundation under Grant No. CMMI-1538730.

  14. Characterization of the Kingella kingae Polysaccharide Capsule and Exopolysaccharide

    PubMed Central

    Starr, Kimberly F.; Porsch, Eric A.; Heiss, Christian; Black, Ian; Azadi, Parastoo; St. Geme, Joseph W.

    2013-01-01

    Recent evidence indicates that Kingella kingae produces a polysaccharide capsule. In an effort to determine the composition and structure of this polysaccharide capsule, in the current study we purified capsular material from the surface of K. kingae strain 269–492 variant KK01 using acidic conditions to release the capsule and a series of steps to remove DNA, RNA, and protein. Analysis of the resulting material by gas chromatography and mass spectrometry revealed N-acetyl galactosamine (GalNAc), 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo), and galactose (Gal). Further analysis by NMR demonstrated two distinct polysaccharides, one consisting of GalNAc and Kdo with the structure →3)-β-GalpNAc-(1→5)-β-Kdop-(2→ and the other containing galactose alone with the structure →5)-β-Galf-(1→. Disruption of the ctrA gene required for surface localization of the K. kingae polysaccharide capsule resulted in elimination of GalNAc and Kdo but had no effect on the presence of Gal in bacterial surface extracts. In contrast, deletion of the pamABCDE locus involved in production of a reported galactan exopolysaccharide eliminated Gal but had no effect on the presence of GalNAc and Kdo in surface extracts. Disruption of ctrA and deletion of pamABCDE resulted in a loss of all carbohydrates in surface extracts. These results establish that K. kingae strain KK01 produces a polysaccharide capsule with the structure →3)-β-GalpNAc-(1→5)-β-Kdop-(2→ and a separate exopolysaccharide with the structure →5)-β-Galf-(1→. The polysaccharide capsule and the exopolysaccharide require distinct genetic loci for surface localization. PMID:24098695

  15. Chemical structure of the O-polysaccharide isolated from Pectobacterium atrosepticum SCRI 1039.

    PubMed

    Czerwicka, Małgorzata; Marszewska, Kinga; Bychowska, Anna; Dziadziuszko, Halina; Brzozowski, Krzysztof; Łojkowska, Ewa; Stepnowski, Piotr; Kaczyński, Zbigniew

    2011-12-27

    The lipopolysaccharide (LPS) of the bacterium Pectobacterium atrosepticum SCRI 1039 was hydrolyzed and the products were separated. A study of the obtained O-polysaccharide by means of chemical methods, GLC, GLC-MS, and NMR spectroscopy allowed us to identify a branched polymer with a pentasaccharide repeating unit of the structure shown below, in which the fucose residue was partially O-acetylated at C-2, C-3 or C-4.

  16. Structural and Immunological Activity Characterization of a Polysaccharide Isolated from Meretrix meretrix Linnaeus

    PubMed Central

    Li, Li; Li, Heng; Qian, Jianying; He, Yongfeng; Zheng, Jialin; Lu, Zhenming; Xu, Zhenghong; Shi, Jinsong

    2015-01-01

    Polysaccharides from marine clams perform various biological activities, whereas information on structure is scarce. Here, a water-soluble polysaccharide MMPX-B2 was isolated from Meretrix meretrix Linnaeus. The proposed structure was deduced through characterization and its immunological activity was investigated. MMPX-B2 consisted of d-glucose and d-galctose residues at a molar ratio of 3.51:1.00. The average molecular weight of MMPX-B2 was 510 kDa. This polysaccharide possessed a main chain of (1→4)-linked-α-d-glucopyranosyl residues, partially substituted at the C-6 position by a few terminal β-d-galactose residues or branched chains consisting of (1→3)-linked β-d-galactose residues. Preliminary immunological tests in vitro showed that MMPX-B2 could stimulate the murine macrophages to release various cytokines, and the structure-activity relationship was then established. The present study demonstrated the potential immunological activity of MMPX-B2, and provided references for studying the active ingredients in M. meretrix. PMID:26729136

  17. Structure analysis of water-soluble polysaccharide CPPS3 isolated from Codonopsis pilosula.

    PubMed

    Zhang, Ya-jun; Zhang, Li-xia; Yang, Jing-feng; Liang, Zhong-yan

    2010-04-01

    Codonopsis pilosula is a perennial species of flowering plants propagated in Northeast Asia. A water-soluble polysaccharide, CPPS(3), was extracted from the root of Codonopsis pilosula by boiled water extraction and ethanol precipitation. The molecular weight was estimated to be 7.4 x 10(4) Da determined by using Gel permeation chromatography. Monosaccharide composition and the structure of the polysaccharide were determined by gas spectroscopy, Fourier transform IR (FT-IR) spectroscopy, NMR spectroscopy and mass spectroscopy and some chemical method analysis was made. The components were galactose, arabinose and rhamnose in the molar ratio of 1.13:1.12:1. The main chain of CPPS(3) is illustrated to be (1-->3)-linked-beta-GalpNAc, (1-->3)-linked-alpha-Rhap and (1-->2,3)-beta-Galp.

  18. Structural analysis and antioxidant activities of polysaccharide isolated from Jinqian mushroom.

    PubMed

    Liu, Yong; Du, Yi-Qun; Wang, Jun-Hui; Zha, Xue-Qiang; Zhang, Jian-Bo

    2014-03-01

    Jinqian mushroom is a precious edible mushroom with delicious taste and high nutritional value. In this paper, a polysaccharide fraction JQPs was isolated and purified from the fruiting body of Jinqian mushroom. The chemical structure, chain conformation and antioxidant activities of JQPs were investigated. The results indicated that JQPs was mainly composed of glucose with trace amounts of xylose. The backbone of JQPs consisted of β-(1 → 3)-D-glucan with β-(1 → 6)-glucosyl side chain. The chain conformation analysis showed that JQPs was a triple helical polysaccharide. The antioxidant activity tests in vitro revealed that JQPs exhibited high DPPH radical and ABTS radical scavenging activities, moderate superoxide radical and hydroxyl radical scavenging activities, low reducing power and Fe(2+) chelating activities. The results suggested that JQPs could be used as a potential natural antioxidant.

  19. Structural Characterization of the Extracellular Polysaccharide from Vibrio cholerae O1 El-Tor

    PubMed Central

    Yildiz, Fitnat; Fong, Jiunn; Sadovskaya, Irina; Grard, Thierry; Vinogradov, Evgeny

    2014-01-01

    The ability to form biofilms is important for environmental survival, transmission, and infectivity of Vibrio cholerae, the causative agent of cholera in humans. To form biofilms, V. cholerae produces an extracellular matrix composed of proteins, nucleic acids and a glycoconjugate, termed Vibrio exopolysaccharide (VPS). Here, we present the data on isolation and characterization of the polysaccharide part of the VPS (VPS-PS), which has the following structure: where α-D-Glc is partially (∼20%) replaced with α-D-GlcNAc. α-GulNAcAGly is an amide between 2-acetamido-2-deoxy-α-guluronic acid and glycine. Apparently, the polysaccharide is bound to a yet unidentified component, which gives it high viscosity and completely suppresses any NMR signals belonging to the sugar chains of the VPS. The only reliable method to remove this component at present is a treatment of the whole glycoconjugate with concentrated hydrochloric acid. PMID:24520310

  20. Structural elucidation of polysaccharide containing 3-O-methyl galactose from fruiting bodies of Pleurotus citrinopileatus.

    PubMed

    He, Pengfei; Zhang, Anqiang; Zhou, Saijing; Zhang, Fuming; Linhardt, Robert J; Sun, Peilong

    2016-11-03

    A water-soluble polysaccharide containing 3-O-methyl galactose (PCP60W) was isolated from fruiting bodies of Pleurotus citrinopileatus and purified by anion-exchange and gel column chromatography. This polysaccharide has an average molecular weight of 2.74 × 10(4) Da and its structure was elucidated using monosaccharide composition and methylation analysis combined with one- and two-dimensional (COSY, TOCSY, NOESY, HMQC and HMBC) NMR spectroscopy. PCP60W was shown to be a linear partially 3-O-methylated α-galactopyranan comprised of 6-linked galactose, 6-linked 3-O-methyl galactose and 4-linked glucose in a ratio of 3.0:1.0:0.6. This work provides additional evidence for the view that 3-O-methyl galactose is common to the genus Pleurotus.

  1. Structure-function relationship of anticoagulant and antithrombotic well-defined sulfated polysaccharides from marine invertebrates.

    PubMed

    Pomin, Vitor H

    2012-01-01

    Marine sulfated polysaccharides (MSPs), such as sulfated fucans (SFs), sulfated galactans (SGs), and glycosaminoglycans (GAGs) isolated from invertebrate animals, are highly anionic polysaccharides capable of interacting with certain cationic proteins, such as (co)-factors of the coagulation cascade during clotting-inhibition process. Primarily, these molecular complexes between MSPs and coagulation-related proteins seem to be driven mostly by electrostatic interactions. However, through a systematic comparison using several novel well-defined sulfated polysaccharides composed of repetitive oligosaccharides with clear sulfation patterns, it was proved that those molecular interactions are essentially regulated by the stereochemistry of the glycans (which depends on a conjunction of anomeric configurations, sugar types, conformational preferences, glycosylation, and sulfation sites), rather than just a mere consequence of the electronegative density charges (mainly from number of sulfate groups). Here, we present an overview about the structure-function relationship of the invertebrate MSPs with regular structures as potential anticoagulant and antithrombotic agents, as pathologies related to the cardiovascular system are one of the major causes of mortality in the world.

  2. PCR for capsular typing of Haemophilus influenzae.

    PubMed Central

    Falla, T J; Crook, D W; Brophy, L N; Maskell, D; Kroll, J S; Moxon, E R

    1994-01-01

    A PCR method for the unequivocal assignment of Haemophilus influenzae capsular type (types a to f) was developed. PCR primers were designed from capsule type-specific DNA sequences cloned from the capsular gene cluster of each of the six capsular types. PCR product was amplified only from the capsular type for which the primers were designed. Product was confirmed by using either an internal oligonucleotide or restriction endonuclease digestion. A total of 172 H. influenzae strains of known capsular type (determined genetically) comprising all capsular types and noncapsulate strains were tested by PCR capsular typing. In all cases the PCR capsular type corresponded to the capsular genotype determined by restriction fragment length polymorphism analysis of the cap region. When used in conjunction with PCR primers derived from the capsular gene bexA, capsulate, noncapsulate, and capsule-deficient type b mutant strains could be differentiated. PCR capsular typing overcomes the problems of cross-reaction and autoagglutination associated with the serotyping of H. influenzae strains. The rapid and unequivocal capsular typing method that is described will be particularly important for typing invasive H. influenzae strains isolated from recipients of H. influenzae type b vaccine. Images PMID:7814470

  3. Fungal polysaccharides.

    PubMed

    San-Blas, G; Suzuki, S; Hearn, V; Pinel, C; Kobayashi, H; Mendez, C; Niño, G; Nishikawa, A; San-Blas, F; Shibata, N

    1994-01-01

    Fungal polysaccharides are cell wall components which may act as antigens or as structural substrates. As antigens, the role of mannans in Saccharomyces cerevisiae and Candida albicans, and of glycoproteins in Aspergillus fumigatus are discussed. Analyses on beta-glucan synthetase in Paracoccidioides brasiliensis and the inhibitory effect of Hansenula mrakii killer toxin on beta-glucan biosynthesis are also considered.

  4. Structural characterization and immunomodulatory effect of a polysaccharide HCP-2 from Houttuynia cordata.

    PubMed

    Cheng, Bao-Hui; Chan, Judy Yuet-Wa; Chan, Ben Chung-Lap; Lin, Huang-Quan; Han, Xiao-Qiang; Zhou, Xuelin; Wan, David Chi-Cheong; Wang, Yi-Fen; Leung, Ping-Chung; Fung, Kwok-Pui; Lau, Clara Bik-San

    2014-03-15

    Immunomodulation of natural polysaccharides has been the hot topic of research in recent years. In order to explore the immunomodulatory effect of Houttuynia cordata Thunb., the water extract was studied and a polysaccharide HCP-2 with molecular weight of 60,000 Da was isolated by chromatography using DEAE Sepharose CL-6B and Sephacryl S-500 [corrected] HR columns. The structure characterization of HCP-2 was performed by Fourier transform infrared spectroscopy (FTIR), acidic hydrolysis, PMP derivation, HPLC analysis and nuclear magnetic resonance spectra (NMR). HCP-2 was elucidated as a pectic polysaccharide with a linear chain of 1,4-linked α-D-galacturonic acid residues in which part of the 6-carboxyl groups were methyl esterified and part of 2-hydroxyl groups were acetylated. The bioactivity assays showed that HCP-2 could increase the secretions of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), macrophage inhibitory protein-1α (MIP-1α), macrophage inhibitory protein-1β (MIP-1β), and RANTES (regulated on activation, normal T cell expressed and secreted) in human peripheral blood mononuclear cells (PBMCs), which play critical roles in the innate immune system and shape the adaptive immunity. Our results implied that HCP-2 could be an immune enhancer.

  5. Structure, chain conformation, and immunomodulatory activity of the polysaccharide purified from Bacillus Calmette Guerin formulation.

    PubMed

    Liu, Wei; Wang, Hong; Yu, Juping; Liu, Yameng; Lu, Weisheng; Chai, Yin; Liu, Chao; Pan, Chun; Yao, Wenbing; Gao, Xiangdong

    2016-10-05

    A polysaccharide, coded as BDP, purified from the injection powder of Bacillus Calmette Guerin (BCG) polysaccharide and nucleic acid, was composed mainly of α-D-(1→4)-linked glucan with (1→6)-linked branches and trace amounts of fucose and mannose from the results of FT-IR, HPAEC-PAD and NMR spectrum. The Mw, Mn, Mz, and [Formula: see text] were determined to be 1.320×10(5)g/mol, 1.012×10(5)g/mol, 2.139×10(5)g/mol, and 21.8±3.2%nm by using HPSEC-MALLS, respectively. The ν value from [Formula: see text] was calculated to be 0.52±0.01, which firstly clarified that BDP existed as random coils in 0.9% NaCl aqueous solution. AFM and SEM combined with Congo-red test also revealed that the polysaccharide was irregular globular like or curly structure. Furthermore, in vitro tests on RAW264.7 murine macrophages cells revealed that BDP exhibited significant immunomodulatory activity.

  6. Structural elucidation and immunostimulatory activity of polysaccharide isolated by subcritical water extraction from Cordyceps militaris.

    PubMed

    Luo, Xiaoping; Duan, Yuqing; Yang, Wenya; Zhang, Haihui; Li, Changzheng; Zhang, Jixian

    2017-02-10

    Water-soluble polysaccharides were obtained from Cordyceps militaris (C. militaris) (CMP) by subcritical water extraction (SWE). Two polysaccharides fractions, CMP-W1 and CMP-S1, were isolated from CMP using DEAE-52 cellulose and Sephadex G-150 column chromatography. The structural characteristics of CMP-W1 and CMP-S1 were investigated. The results showed that the molecular weight of CMP-W1 and CMP-S1 are 3.66×105Da and 4.60×105Da, respectively, and both of them were heteropolysaccharides composed of d-mannose, d-glucose, d-galactose with the molar ratios of 2.84:1:1.29 and 2.05:1:1.09, respectively. FT-IR spectra analysis suggested that CMP-W1 and CMP-S1 belonged to pyranose form sugar and protein free. For immunostimulatory activity assay in vitro, CMP-W1 and CMP-S1 significantly promoted lymphatic spleen cell proliferation of mice. Therefore, the polysaccharides obtained from C. militaris by SWE can be used as potential natural immunostimulant in functional foods or medicine.

  7. Structural characterization of polysaccharide obtained from red seaweed Gracilaria caudata (J Agardh).

    PubMed

    Barros, Francisco C N; da Silva, Draulio C; Sombra, Venicios G; Maciel, Jeanny S; Feitosa, Judith P A; Freitas, Ana L P; de Paula, Regina C M

    2013-01-30

    Seaweeds are considered an important source of bioactive molecules. In this work the marine red alga Gracilaria caudata was submitted to aqueous extraction of their polysaccharides for 2 h at 100 °C. The polysaccharide fraction (PGC) presented a recovery of 32.8%. The sulfate content of PGC, calculated by S%, is 1 ± 0.2% and the degree of sulfation accounts for 0.13 ± 0.2. High-Performance Size-Exclusion Chromatography demonstrated that PGC consists of a high molecular weight polysaccharide (2.5 × 10(5)gmol(-1)). Chemical analysis of PGC was performed by microanalysis, infrared (FT-IR) and nuclear magnetic resonance (NMR, 1 and 2D) spectroscopy. The structure of PGC is mainly constituted by the alternating residues 3-linked-β-D-galactopyranose and 4-linked-3,6-α-L-anhydrogalactose; however some hydroxyl groups were substituted by methyl groups and pyruvic acid acetal. The biological precursor of 3,6-α-L-anhydrogalactose (6-sulfate-α-l-galactose) was also detected.

  8. Capsular Weakness around Breast Implant: A Non-Recognized Complication

    PubMed Central

    Arquero, Pedro Salinero; Zanata, Fabiana Cristina; Ferreira, Lydia Masako; Nahas, Fabio Xerfan

    2015-01-01

    Capsular contraction is a frequent complication following breast augmentation. On the other hand, capsular weakness, a not widely recognized complication, may occur around the implant. A weak capsule allows the migration of the prosthesis to the lateral region of the thoracic region or inferiorly, towards the abdomen, due to gravitational forces. The cause of capsular weakness remains unresolved. Implant malposition, with lateral or downward displacement, breast asymmetry, improper contour, with implants moving in the pocket that compromise the aesthetic outcome of breast augmentation and require surgical correction may be different symptoms from the same clinical problem. Capsular weakness is a short or mid-term complication of breast augmentation. Most techniques aim to correct the malposition by making sutures to increase the resistance to the displacement of the implant, rearrange the structures using the capsule as flaps to remodel the envelope of the new pocket, obtaining a more stable and reliable result. In this article, four cases of displacement of breast prosthesis with capsular weakness are described and the surgical treatment that included a capsulotomy and capsulorraphy is described. PMID:26284187

  9. Automatic structure determination of regular polysaccharides based solely on NMR spectroscopy.

    PubMed

    Lundborg, Magnus; Fontana, Carolina; Widmalm, Göran

    2011-11-14

    The structural analysis of polysaccharides requires that the sugar components and their absolute configurations are determined. We here show that this can be performed based on NMR spectroscopy by utilizing butanolysis with (+)- and (-)-2-butanol that gives the corresponding 2-butyl glycosides with characteristic (1)H and (13)C NMR chemical shifts. The subsequent computer-assisted structural determination by CASPER can then be based solely on NMR data in a fully automatic way as shown and implemented herein. The method is additionally advantageous in that reference data only have to be prepared once and from a user's point of view only the unknown sample has to be derivatized for use in CASPER.

  10. Structure and Properties of Polysaccharide Based BioPolymer Gels

    NASA Astrophysics Data System (ADS)

    Prud'Homme, Robert K.

    2000-03-01

    Nature uses the pyranose ring as the basic building unit for a wideclass of biopolymers. Because of their biological origin these biopolymers naturally find application as food additives, rheology modifiers. These polymers range from being rigid skeletal material, such as cellulose that resist dissolution in water, to water soluble polymers, such as guar or carrageenan. The flexibility of the basic pyranose ring structure to provide materials with such a wide range of properties comes from the specific interactions that can be engineered by nature into the structure. We will present several examples of specific interactions for these systems: hydrogen bonding, hydrophobic interactions, and specific ion interactions. The relationship between molecular interations and rheology will be emphasized. Hydrogen bonding mediated by steric interference is used to control of solubility of starch and the rheology of guar gels. A more interesting example is the hydrogen bonding induced by chemical modification in konjac glucomannan that results in a gel that melts upon cooling. Hydrogen bonding interactions in xanthan lead to gel formation at very low polymer concentrations which is a result of the fine tuning of the polymer persistence length and total contour length. Given the function of xanthan in nature its molecular architecture has been optimized. Hydrophobic interactions in methylcellulose show a reverse temperature dependence arising from solution entropy. Carrageenan gelation upon the addition of specific cations will be addressed to show the interplay of polymer secondary structure on chemical reactivity. And finally the cis-hydroxyls on galactomannans permit crosslinking by a variety of metal ions some of which lead to "living gels" and some of which lead to permanently crosslinked networks.

  11. A computer-assisted structural analysis of regular polysaccharides on the basis of 13C-n.m.r. data.

    PubMed

    Lipkind, G M; Shashkov, A S; Knirel, Y A; Vinogradov, E V; Kochetkov, N K

    1988-04-01

    A computerised approach to the structural analysis of unbranched regular polysaccharides is described, which is based on an evaluation of the 13C-n.m.r. spectra for all possible primary structures within the additive scheme starting from the chemical shifts of the 13C resonances of the constituent monosaccharides and the average values of the glycosylation effects. The analysis reveals a structure (or structures), the evaluated spectrum of which resembles most closely that observed. The approach has been verified by using a series of bacterial polysaccharides of known structure and, in combination with methylation analysis data, for the determination of the presently unknown structures of the O-specific polysaccharides from Salmonella arizonae O59 and O63, and Proteus hauseri O19.

  12. An Interesting Class of Porous Polymer--Revisiting the Structure of Mesoporous α-D-Polysaccharide Gels.

    PubMed

    White, Robin J; Shuttleworth, Peter S; Budarin, Vitaliy L; De Bruyn, Mario; Fischer, Anna; Clark, James H

    2016-02-08

    The processes involved in the transformation of non-porous, native polysaccharides to their highly porous equivalents introduce significant molecular complexity and are not yet fully understood. In this paper, we propose that distinct changes in polysaccharide local short-range ordering promotes and directs the formation of meso- and micro-pores, which are investigated here using N2 sorption, FTIR, and solid-state (13)C NMR. It is found that an increase in the overall double helical amylose content, and their local association structures, are responsible for formation of the porous polysaccharide gel phase. An exciting consequence of this local ordering change is elegantly revealed using a (19)F NMR experiment, which identifies the stereochemistry-dependent diffusion of a fluorinated chiral probe molecule (1-phenyl-2,2,2-trifluoroethanol) from the meso- to the micro-pore region. This finding opens opportunities in the area of polysaccharide-based chiral stationary phases and asymmetric catalyst preparation.

  13. Purification, structure and immunobiological activity of an arabinan-rich pectic polysaccharide from the cell walls of Prunus dulcis seeds.

    PubMed

    Dourado, Fernando; Madureira, Pedro; Carvalho, Vera; Coelho, Ricardo; Coimbra, Manuel A; Vilanova, Manuel; Mota, Manuel; Gama, Francisco M

    2004-10-20

    The structure and bioactivity of a polysaccharide extracted and purified from a 4M KOH + H3BO3 solution from Prunus dulcis seed cell wall material was studied. Anion-exchange chromatography of the crude extract yielded two sugar-rich fractions: one neutral (A), the other acidic (E). These fractions contain a very similar monosaccharide composition: 5:2:1 for arabinose, uronic acids and xylose, respectively, rhamnose and galactose being present in smaller amounts. As estimated by size-exclusion chromatography, the acidic fraction had an apparent molecular mass of 762 kDa. Methylation analysis (from the crude and fractions A and E), suggests that the polysaccharide is an arabinan-rich pectin. In all cases, the polysaccharides bear the same type of structural Ara moieties with highly branched arabinan-rich pectic polysaccharides. The average relative proportions of the arabinosyl linkages is 3:2:1:1 for T-Araf:(1-->5)-Araf:(1-->3,5)-Araf:(1-->2,3,5)-Araf. The crude polysaccharide extract and fractions A and E induced a murine lymphocyte stimulatory effect, as evaluated by the in vitro and in vivo expression of lymphocyte activation markers and spleen mononuclear cells culture proliferation. The lymphocyte stimulatory effect was stronger on B- than on T-cells. No evidence of cytotoxic effects induced by the polysaccharide fractions was found.

  14. Structures of the O-polysaccharides and classification of Proteus genomospecies 4, 5 and 6 into respective Proteus serogroups.

    PubMed

    Zych, Krystyna; Perepelov, Andrei V; Siwinska, Małgorzata; Knirel, Yuriy A; Sidorczyk, Zygmunt

    2005-11-01

    An acidic branched O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide (LPS) of Proteus genomospecies 4 and studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, ROESY and H-detected 1H, 13C HSQC experiments. The following structure of the pentasaccharide repeating unit of the O-polysaccharide was established, which is unique among Proteus polysaccharide structures: [structure: see text] where Qui3NAc stands for 3-acetamido-3,6-dideoxyglucose. Based on the O-polysaccharide structure and serological data, we propose classifying Proteus genomospecies 4 into a new, separate Proteus serogroup, O56. A weak cross-reactivity of Proteus genomospecies 4 antiserum with LPS of Providencia stuartii O18 and Proteus vulgaris OX2 was observed and is discussed in view of a similarity of the O-polysaccharide structures. Structural and serological investigations showed that Proteus genomospecies 5 and 6 should be classified into the existing Proteus serogroups O8 and O69, respectively.

  15. Salinity-Induced Anti-Angiogenesis Activities and Structural Changes of the Polysaccharides from Cultured Cordyceps Militaris

    PubMed Central

    Zeng, Yangyang; Han, Zhangrun; Qiu, Peiju; Zhou, Zijing; Tang, Yang; Zhao, Yue; Zheng, Sha; Xu, Chenchen; Zhang, Xiuli; Yin, Pinghe; Jiang, Xiaolu; Lu, Hong; Yu, Guangli; Zhang, Lijuan

    2014-01-01

    Cordyceps is a rare and exotic mushroom that grows out of the head of a mummified caterpillar. Many companies are cultivating Cordyceps to meet the increased demand for its medicinal applications. However, the structures and functions of polysaccharides, one of the pharmaceutical active ingredients in Cordyceps, are difficult to reproduce in vitro. We hypothesized that mimicking the salty environment inside caterpillar bodies might make the cultured fungus synthesize polysaccharides with similar structures and functions to that of wild Cordyceps. By adding either sodium sulfate or sodium chloride into growth media, we observed the salinity-induced anti-angiogenesis activities of the polysaccharides purified from the cultured C. Militaris. To correlate the activities with the polysaccharide structures, we performed the 13C-NMR analysis and observed profound structural changes including different proportions of α and β glycosidic bonds and appearances of uronic acid signals in the polysaccharides purified from the culture after the salts were added. By coupling the techniques of stable 34S-sulfate isotope labeling, aniline- and D5-aniline tagging, and stable isotope facilitated uronic acid-reduction with LC-MS analysis, our data revealed for the first time the existence of covalently linked sulfate and the presence of polygalacuronic acids in the polysaccharides purified from the salt added C. Militaris culture. Our data showed that culturing C. Militaris with added salts changed the biosynthetic scheme and resulted in novel polysaccharide structures and functions. These findings might be insightful in terms of how to make C. Militaris cultures to reach or to exceed the potency of wild Cordyceps in future. PMID:25203294

  16. Diatom-Specific Oligosaccharide and Polysaccharide Structures Help to Unravel Biosynthetic Capabilities in Diatoms.

    PubMed

    Gügi, Bruno; Le Costaouec, Tinaïg; Burel, Carole; Lerouge, Patrice; Helbert, William; Bardor, Muriel

    2015-09-18

    Diatoms are marine organisms that represent one of the most important sources of biomass in the ocean, accounting for about 40% of marine primary production, and in the biosphere, contributing up to 20% of global CO₂ fixation. There has been a recent surge in developing the use of diatoms as a source of bioactive compounds in the food and cosmetic industries. In addition, the potential of diatoms such as Phaeodactylum tricornutum as cell factories for the production of biopharmaceuticals is currently under evaluation. These biotechnological applications require a comprehensive understanding of the sugar biosynthesis pathways that operate in diatoms. Here, we review diatom glycan and polysaccharide structures, thus revealing their sugar biosynthesis capabilities.

  17. Capsules from Pathogenic and Non-Pathogenic Cryptococcus spp. Manifest Significant Differences in Structure and Ability to Protect against Phagocytic Cells

    PubMed Central

    Araujo, Glauber de S.; Fonseca, Fernanda L.; Pontes, Bruno; Torres, Andre; Cordero, Radames J. B.; Zancopé-Oliveira, Rosely M.; Casadevall, Arturo; Viana, Nathan B.; Nimrichter, Leonardo; Rodrigues, Marcio L.; Garcia, Eloi S.; de Souza, Wanderley; Frases, Susana

    2012-01-01

    Capsule production is common among bacterial species, but relatively rare in eukaryotic microorganisms. Members of the fungal Cryptococcus genus are known to produce capsules, which are major determinants of virulence in the highly pathogenic species Cryptococcus neoformans and Cryptococcus gattii. Although the lack of virulence of many species of the Cryptococcus genus can be explained solely by the lack of mammalian thermotolerance, it is uncertain whether the capsules from these organisms are comparable to those of the pathogenic cryptococci. In this study, we compared the characteristic of the capsule from the non-pathogenic environmental yeast Cryptococcus liquefaciens with that of C. neoformans. Microscopic observations revealed that C. liquefaciens has a capsule visible in India ink preparations that was also efficiently labeled by three antibodies generated to specific C. neoformans capsular antigens. Capsular polysaccharides of C. liquefaciens were incorporated onto the cell surface of acapsular C. neoformans mutant cells. Polysaccharide composition determinations in combination with confocal microscopy revealed that C. liquefaciens capsule consisted of mannose, xylose, glucose, glucuronic acid, galactose and N-acetylglucosamine. Physical chemical analysis of the C. liquefaciens polysaccharides in comparison with C. neoformans samples revealed significant differences in viscosity, elastic properties and macromolecular structure parameters of polysaccharide solutions such as rigidity, effective diameter, zeta potential and molecular mass, which nevertheless appeared to be characteristics of linear polysaccharides that also comprise capsular polysaccharide of C. neoformans. The environmental yeast, however, showed enhanced susceptibility to the antimicrobial activity of the environmental phagocytes, suggesting that the C. liquefaciens capsular components are insufficient in protecting yeast cells against killing by amoeba. These results suggest that capsular

  18. Structural characterization and functional properties of antihypertensive Cymodocea nodosa sulfated polysaccharide.

    PubMed

    Kolsi, Rihab Ben Abdallah; Fakhfakh, Jawhar; Krichen, Fatma; Jribi, Imed; Chiarore, Antonia; Patti, Francesco Paolo; Blecker, Christophe; Allouche, Noureddine; Belghith, Hafedh; Belghith, Karima

    2016-10-20

    A sulfated polysaccharide was successfully isolated from Cymodocea nodosa (CNSP). This is the first report that indicates the chemical composition, structural characterization, functional and antihypertensive properties of this polysaccharide. The CNSP consisted mainly of sulfate (23.17%), total sugars (54.90%), galactose (44.89%), mannose (17.30%), arabinose (12.05%), xylose (9.18%), maltose (1.07%) and uronic acid (11.03%) with low water activity (0.49). CNSP had an XRD pattern that was typical for a semi-crystalline polymer with homogeneous structure. It also displayed an important anti-hypertensive activity (IC50=0.43mgml) with a dose-dependent manner using a synthetic substrate, N-hippuryl-His-Leu hydrate salt (HHL). Overall, the results indicate that CNSP have attractive chemical, functional and biological properties, with a preliminary structural may have a backbone of branched 6-O-sulfated (1→4) galactosidic linkages, which can be considered in the future as alternative additive in various foods, cosmetic and pharmaceutical preparations.

  19. Cereal non-cellulosic polysaccharides: structure and function relationship - an overview.

    PubMed

    Muralikrishna, G; Rao, M V S S T Subba

    2007-01-01

    The non-cellulosic polysaccharides present in cereals (2-8%) are mostly arabinoxylans, (1 --> 3),(1 --> 4)-beta -glucans, pectins and arabinogalactans. Of these, the arabinoxylans are known to absorb large amounts of water and influence significantly the water balance, rheological properties of dough, and the retrogradation of starch and bread quality. (1 --> 3),(1 --> 4)-beta -glucans are known as biological response modifiers (BMS) as they are believed to modulate the immune response. Cereal Pectins and arabinogalactans form a very small amount and do not contribute substantially to the functionality of noncellulosic polysaccharides. Detailed structural investigations on cereal hetero xylans using modern techniques were initiated in the 1990s and still pose a challenge to carbohydrate chemists because of their structural complexity. Nutritionally, they are classified under "unavailable carbohydrates" (dietary fiber) along with lignin and cellulose and are known to have beneficial effects in alleviating disease symptoms such as diabetes, atherosclerosis, and colon cancer. In this review isolation, purification, characterization, structural elucidation, functional, and nutritional attributes of cereal heteroxylans are covered with particular emphasis on recently characterized finger millet arabinoxylans.

  20. Structural and Functional Characterization of a Lytic Polysaccharide Monooxygenase with Broad Substrate Specificity*

    PubMed Central

    Borisova, Anna S.; Isaksen, Trine; Dimarogona, Maria; Kognole, Abhishek A.; Mathiesen, Geir; Várnai, Anikó; Røhr, Åsmund K.; Payne, Christina M.; Sørlie, Morten; Sandgren, Mats; Eijsink, Vincent G. H.

    2015-01-01

    The recently discovered lytic polysaccharide monooxygenases (LPMOs) carry out oxidative cleavage of polysaccharides and are of major importance for efficient processing of biomass. NcLPMO9C from Neurospora crassa acts both on cellulose and on non-cellulose β-glucans, including cellodextrins and xyloglucan. The crystal structure of the catalytic domain of NcLPMO9C revealed an extended, highly polar substrate-binding surface well suited to interact with a variety of sugar substrates. The ability of NcLPMO9C to act on soluble substrates was exploited to study enzyme-substrate interactions. EPR studies demonstrated that the Cu2+ center environment is altered upon substrate binding, whereas isothermal titration calorimetry studies revealed binding affinities in the low micromolar range for polymeric substrates that are due in part to the presence of a carbohydrate-binding module (CBM1). Importantly, the novel structure of NcLPMO9C enabled a comparative study, revealing that the oxidative regioselectivity of LPMO9s (C1, C4, or both) correlates with distinct structural features of the copper coordination sphere. In strictly C1-oxidizing LPMO9s, access to the solvent-facing axial coordination position is restricted by a conserved tyrosine residue, whereas access to this same position seems unrestricted in C4-oxidizing LPMO9s. LPMO9s known to produce a mixture of C1- and C4-oxidized products show an intermediate situation. PMID:26178376

  1. Microwave-Assisted Extraction, Chemical Structures, and Chain Conformation of Polysaccharides from a Novel Cordyceps Sinensis Fungus UM01.

    PubMed

    Cheong, Kit-Leong; Wang, Lan-Ying; Wu, Ding-Tao; Hu, De-Jun; Zhao, Jing; Li, Shao-Ping

    2016-09-01

    Cordyceps sinensis is a well-known tonic food with broad medicinal properties. The aim of the present study was to investigate the optimization of microwave-assisted extraction (MAE) and characterize chemical structures and chain conformation of polysaccharides from a novel C. sinensis fungus UM01. Ion-exchange and gel filtration chromatography were used to purify the polysaccharides. The chemical structure of purified polysaccharide was determined through gas chromatography-mass spectrometry. Moreover, high performance size exclusion chromatography combined with refractive index detector and multiangle laser light scattering were conducted to analyze the molecular weight (Mw ) and chain conformation of purified polysaccharide. Based on the orthogonal design L9 , optimal MAE conditions could be obtained through 1300 W of microwave power, with a 5-min irradiation time at a solid to water ratio of 1:60, generating the highest extraction yield of 6.20%. Subsequently, the polysaccharide UM01-S1 was purified. The UM01-S1 is a glucan-type polysaccharide with a (1→4)-β-d-glucosyl backbone and branching points located at O-3 of Glcp with a terminal-d-Glcp. The Mw , radius of gyration (Rg ) and hydrodynamic radius (Rh ) of UM01-S1 were determined as 5.442 × 10(6)  Da, 21.8 and 20.2 nm, respectively. Using the polymer solution theory, the exponent (ν) value of the power law function was calculated as 0.38, and the shape factor (ρ = Rg /Rh ) was 1.079, indicating that UM01-S1 has a sphere-like conformation with a branched structure in an aqueous solution. These results provide fundamental information for the future application of polysaccharides from cultured C. sinensis in health and functional food area.

  2. Primary Frozen Shoulder Syndrome: Arthroscopic Capsular Release

    PubMed Central

    Arce, Guillermo

    2015-01-01

    Idiopathic adhesive capsulitis, or primary frozen shoulder syndrome, is a fairly common orthopaedic problem characterized by shoulder pain and loss of motion. In most cases, conservative treatment (6-month physical therapy program and intra-articular steroid injections) improves symptoms and restores shoulder motion. In refractory cases, arthroscopic capsular release is indicated. This surgical procedure carries several advantages over other treatment modalities. First, it provides precise and controlled release of the capsule and ligaments, reducing the risk of traumatic complications observed after forceful shoulder manipulation. Second, release of the capsule and the involved structures with a radiofrequency device delays healing, which prevents adhesion formation. Third, the technique is straightforward, and an oral postoperative steroid program decreases pain and allows for a pleasant early rehabilitation program. Fourth, the procedure is performed with the patient fully awake under an interscalene block, which boosts the patient's confidence and adherence to the physical therapy protocol. In patients with refractory primary frozen shoulder syndrome, arthroscopic capsular release emerges as a suitable option that leads to a faster and long-lasting recovery. PMID:26870652

  3. Structural characterization and antioxidant activity in vitro of polysaccharides from angelica and astragalus.

    PubMed

    Pu, Xiuying; Ma, Xiaolong; Liu, Lu; Ren, Jing; Li, Haibing; Li, Xiaoyue; Yu, Shuang; Zhang, Weijie; Fan, Wenbo

    2016-02-10

    In the present study, structural characterization and antioxidant activity of a fraction (AAP-2A) of polysaccharides from angelica and astragalus (AAP) were investigated. Characteriztion assay showed that AAP-2A had molecular weight (Mw), root-mean square (RMS) radius and polydispersity index (Mw/Mn) of 2.252 × 10(3)kDa, 28.4 nm and 1.038, respectively. There were infrared characteristic absorption peaks of polysaccharides in FT-IR spectroscopy. AAP-2A was composed of rhamnose (Rha), galactose (Gal), arabinose (Ara) and glucose (Glc) with a molar ratio of 1:2.13:3.22:6.18 in GC analysis. Methylation analysis combined with NMR spectroscopic analysis demonstrated that a preliminary structure of AAP-2A was proposed as follows: 1,3-linked Rhap, 1,3-linked Galp, 1,3-linked Araf, 1,5-linked Araf, 1,3,5-linked Araf, 1,4-linked Glcp and 1,4,6-linked Glcp interspersed with terminal Glcp. AAP-2A exhibited a surface with a sheet-like appearance in scanning electron microscope and stronger antioxidant capacity compared with AAP.

  4. Structure and optical properties of noble metal and oxide nanoparticles dispersed in various polysaccharide biopolymers

    NASA Astrophysics Data System (ADS)

    Djoković, V.; Božanic, D. K.; Vodnik, V. V.; Krsmanović, R. M.; Trandafilovic, L. V.; Dimitrijević-Branković, S.

    2011-10-01

    We present the results on the structure and the optical properties of noble metal (Ag, Au) and oxide (ZnO) nanoparticles synthesized by various methods in different polysaccharide matrices such as chitosan, glycogen, alginate and starch. The structure of the obtained nanoparticles was studied in detail with microscopic techniques (TEM, SEM), while the XPS spectroscopy was used to investigate the effects at the nanoparticle-biomolecule interfaces. The antimicrobial activity of the nanocomposite films with Ag nanoparticles was tested against the Staphylococcus aureus, Escherichia coli and Candida albicans pathogens. In addition, we will present the results on the structure and optical properties of the tryptophan amino acid functionalized silver nanoparticles dispersed in water soluble polymer matrices.

  5. Chemical Modification of Polysaccharides

    PubMed Central

    Cumpstey, Ian

    2013-01-01

    This review covers methods for modifying the structures of polysaccharides. The introduction of hydrophobic, acidic, basic, or other functionality into polysaccharide structures can alter the properties of materials based on these substances. The development of chemical methods to achieve this aim is an ongoing area of research that is expected to become more important as the emphasis on using renewable starting materials and sustainable processes increases in the future. The methods covered in this review include ester and ether formation using saccharide oxygen nucleophiles, including enzymatic reactions and aspects of regioselectivity; the introduction of heteroatomic nucleophiles into polysaccharide chains; the oxidation of polysaccharides, including oxidative glycol cleavage, chemical oxidation of primary alcohols to carboxylic acids, and enzymatic oxidation of primary alcohols to aldehydes; reactions of uronic-acid-based polysaccharides; nucleophilic reactions of the amines of chitosan; and the formation of unsaturated polysaccharide derivatives. PMID:24151557

  6. Structure of the O-polysaccharide leads to classification of Proteus penneri 31 in Proteus serogroup O19.

    PubMed

    Kondakova, Anna N; Zych, Krystyna; Senchenkova, Sof'ya N; Zabłotni, Agnieszka; Shashkov, Alexander S; Knirel, Yuriy A; Sidorczyk, Zygmunt

    2003-10-24

    O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide (LPS) of Proteus penneri strain 31. Sugar and methylation analyses along with NMR spectroscopic studies, including 2D 1H,1H COSY, TOCSY, ROESY, 1H,13C and 1H,31P HMQC experiments, demonstrated the following structure of the polysaccharide: [carbohydrate structure: see text] where FucNAc is 2-acetamido-2,6-dideoxygalactose and EtnP is 2-aminoethyl phosphate. The polysaccharide studied has the same carbohydrate backbone as the O-polysaccharide of Proteus vulgaris O19. Based on this finding and close serological relatedness of the LPS of the two strains, it is proposed to classify P. penneri 31 in Proteus serogroup O19 as an additional subgroup. In contrast, D-GlcNAc6PEtn and alpha-L-FucNAc-(1-->3)-D-GlcNAc shared with a number of other Proteus O-polysaccharides could not provide any significant cross-reactivity of the corresponding LPS with rabbit polyclonal O-antiserum against P. penneri 31.

  7. Capsular Suspension Technique for Hip Arthroscopy

    PubMed Central

    Federer, Andrew E.; Karas, Vasili; Nho, Shane; Coleman, Struan H.; Mather, Richard C.

    2015-01-01

    Hip arthroscopy has recently become a common procedure to treat central and peripheral hip pathology. Capsulotomies are necessary in these procedures, and negotiating adequate visualization, as well as capsular preservation, is a challenge. We describe a capsular suspension technique that allows for adequate visualization of the central and peripheral compartments while facilitating preservation of the native hip capsule. This technique eliminates the need for additional personnel for retraction, potentially decreases iatrogenic hip injury, eliminates the need for excessive capsular debridement, and allows for capsular closure under minimal tension. PMID:26759769

  8. Structure, physical property and antioxidant activity of catechin grafted Tremella fuciformis polysaccharide.

    PubMed

    Liu, Jun; Meng, Chen-Guang; Yan, Ye-Hua; Shan, Ya-Na; Kan, Juan; Jin, Chang-Hai

    2016-01-01

    In this study, structural characterization, physical property and antioxidant activity of catechin grafted Tremella fuciformis polysaccharide (catechin-g-TPS) were investigated. Crude polysaccharides were isolated from the fruit bodies of T. fuciformis and further purified on DEAE-52 and Sepharose CL-4B chromatography to afford a main purified fraction (named TPS). The molecular weight of TPS was determined as 5.82 × 10(5)Da by HPLC. Then, the free radical mediated grafting of catechin onto TPS was achieved by using a redox system. As compared with the unmodified TPS, catechin-g-TPS showed new bands within the range of 1300-1600 cm(-1) in FT-IR spectrum, and exhibited new signals at around δ 6.00 and 6.80 ppm in (1)H NMR spectrum. Thermogravimetric analysis indicated the thermal stability of catechin-g-TPS was higher than TPS. X-ray diffraction spectrum of catechin-g-TPS exhibited two sharp narrow diffraction peaks at 14.2 and 32.1°, corresponding to the crystalline peaks of catechin. Scanning electron microscopy observation revealed the surface of TPS was smooth, whereas the surface of catechin-g-TPS was much rough. These results all confirmed the successful grafting of catechin onto TPS. Moreover, catechin-g-TPS had higher 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power as compared to TPS.

  9. The Structure-Activity Relationship between Marine Algae Polysaccharides and Anti-Complement Activity

    PubMed Central

    Jin, Weihua; Zhang, Wenjing; Liang, Hongze; Zhang, Quanbin

    2015-01-01

    In this study, 33 different polysaccharides were prepared to investigate the structure-activity relationships between the polysaccharides, mainly from marine algae, and anti-complement activity in the classical pathway. Factors considered included extraction methods, fractionations, molecular weight, molar ratio of galactose to fucose, sulfate, uronic acid (UA) content, linkage, branching, and the type of monosaccharide. It was shown that the larger the molecular weights, the better the activities. The molar ratio of galactose (Gal) to fucose (Fuc) was a positive factor at a concentration lower than 10 µg/mL, while it had no effect at a concentration more than 10 µg/mL. In addition, sulfate was necessary; however, the sulfate content, the sulfate pattern, linkage and branching had no effect at a concentration of more than 10 µg/mL. Moreover, the type of monosaccharide had no effect. Laminaran and UA fractions had no activity; however, they could reduce the activity by decreasing the effective concentration of the active composition when they were mixed with the active compositions. The effect of the extraction methods could not be determined. Finally, it was observed that sulfated galactofucan showed good anti-complement activity after separation. PMID:26712768

  10. The Structure-Activity Relationship between Marine Algae Polysaccharides and Anti-Complement Activity.

    PubMed

    Jin, Weihua; Zhang, Wenjing; Liang, Hongze; Zhang, Quanbin

    2015-12-25

    In this study, 33 different polysaccharides were prepared to investigate the structure-activity relationships between the polysaccharides, mainly from marine algae, and anti-complement activity in the classical pathway. Factors considered included extraction methods, fractionations, molecular weight, molar ratio of galactose to fucose, sulfate, uronic acid (UA) content, linkage, branching, and the type of monosaccharide. It was shown that the larger the molecular weights, the better the activities. The molar ratio of galactose (Gal) to fucose (Fuc) was a positive factor at a concentration lower than 10 µg/mL, while it had no effect at a concentration more than 10 µg/mL. In addition, sulfate was necessary; however, the sulfate content, the sulfate pattern, linkage and branching had no effect at a concentration of more than 10 µg/mL. Moreover, the type of monosaccharide had no effect. Laminaran and UA fractions had no activity; however, they could reduce the activity by decreasing the effective concentration of the active composition when they were mixed with the active compositions. The effect of the extraction methods could not be determined. Finally, it was observed that sulfated galactofucan showed good anti-complement activity after separation.

  11. Structure-activity relationship of sulfated hetero/galactofucan polysaccharides on dopaminergic neuron.

    PubMed

    Wang, Jing; Liu, Huaide; Jin, Weihua; Zhang, Hong; Zhang, Quanbin

    2016-01-01

    Parkinson's disease (PD) is associated with progressive loss of dopaminergic neurons and more-widespread neuronal changes that cause complex symptoms. The aim of this study was to investigate the structure-activity relationship of sulfated hetero-polysaccharides (DF1) and sulfated galactofucan polysaccharides (DF2) on dopaminergic neuron in vivo and in vitro. Treatment with samples significantly ameliorated the depletion of both DA and TH-, Bcl-2- and Bax-positive neurons in MPTP-induced PD mice, DF1 showed the highest activity. The in vitro results found that DF1 and DF2 could reverse the decreased mitochondrial activity and the increased LDL release induced by MPP(+) (P<0.01 or P<0.001) which provides further evidence that DF1 and DF2 also exerts a direct protection against the neuronal injury caused by MPP(+). Furthermore, the administration of samples effectively decreased lipid peroxidation and increased the level/activities of GSH, GSH-PX, MDA and CAT in MPTP mice. Thus, the neuron protective effect may be mediated, in part, through antioxidant activity and the prevention of cell apoptosis. The chemical composition of DF1, DF2 and DF differed markedly, the DF1 fraction had the most complex chemical composition and showed the highest neuron protective activity. These results suggest that diverse monosaccharides and uronic acid might contribute to neuron protective activity.

  12. Study of macrophage activation and structural characteristics of purified polysaccharides from the fruiting body of Hericium erinaceus.

    PubMed

    Lee, Jong Seok; Min, Kyoung Min; Cho, Jae Youl; Hong, Eock Kee

    2009-09-01

    Most, if not all, Basidiomycetes mushrooms have biologically active polysaccharides showing potent antitumor activity with immunomodulating properties. These polysaccharides have various chemical compositions and belong primarily to the beta-glucan group. In this study, the crude water-soluble polysaccharide HEF-P, which was obtained from the fruiting body of Hericium erinaceus by hot water extraction and ethanol precipitation, was fractionated by DEAE-cellulose and Sepharose CL-6B column chromatographies. This process resulted in four polysaccharide fractions, named HEF-NP Fr I, HEF-NP Fr II, HEF-AP Fr I, and HEF-AP Fr II. Of these fractions, HEF-AP Fr II was able to upregulate the functional events mediated by activated macrophages, such as production of nitric oxide and expression of cytokines (IL-1beta and TNF-beta). The molecular mass of HEF-AP Fr II was estimated by gel filtration to be 13 kDa. Its structural characteristics were investigated by a combination of chemical and instrumental analyses, including methylation, reductive cleavage, acetylation, Fourier transform infrared spectroscopy (FT-IR), and gas chromatography-mass spectrometry (GC-MS). Results indicate that HEF-AP Fr II is a low-molecular-mass polysaccharide with a laminarin-like triple helix conformation of a beta-1,3-branched-beta-1,6-glucan.

  13. Structures, biological activities, and industrial applications of the polysaccharides from Hericium erinaceus (Lion's Mane) mushroom: A review.

    PubMed

    He, Xirui; Wang, Xiaoxiao; Fang, Jiacheng; Chang, Yu; Ning, Ning; Guo, Hao; Huang, Linhong; Huang, Xiaoqiang; Zhao, Zefeng

    2017-04-01

    Hericium erinaceus (Bull.) Pers., also known as Yamabushitake, Houtou and Lion's Mane, is capable of fortifying the spleen and nourishing the stomach, tranquilizing the mind, and fighting cancer. Over the past decade, it has been demonstrated that H. erinaceus polysaccharides possess various promising bioactivities, including antitumor and immunomodulation, anti-gastric ulcer, neuroprotection and neuroregeneration, anti-oxidation and hepatoprotection, anti-hyperlipidemia, anti-hyperglycemia, anti-fatigue and anti-aging. The purpose of the present review is to provide systematically reorganized information on extraction and purification, structure characteristics, biological activities, and industrial applications of H. erinaceus polysaccharides to support their therapeutic potentials and sanitarian functions.

  14. Pectic polysaccharide from the green fruits of Momordica charantia (Karela): structural characterization and study of immunoenhancing and antioxidant properties.

    PubMed

    Panda, Bibhash C; Mondal, Soumitra; Devi, K Sanjana P; Maiti, Tapas K; Khatua, Somanjana; Acharya, Krishnendu; Islam, Syed S

    2015-01-12

    A water soluble pectic polysaccharide (PS) isolated from the aqueous extract of the green fruits of Momordica charantia contains D-galactose and D-methyl galacturonate in a molar ratio of nearly 1:4. It showed splenocyte, thymocyte as well as macrophage activations. Moreover, it exhibited potent antioxidant activities. On the basis of total acid hydrolysis, methylation analysis, periodate oxidation, and 1D and 2D NMR studies, the structure of the repeating unit of the pectic polysaccharide was established as: [Formula: see text].

  15. [Somatic antigens of the Brucella genus. The structure of the O-specific polysaccharide chain of Brucella melitensis lipopolysaccharide].

    PubMed

    L'vov, V L; Malikov, V E; Shashkov, A S; Dranovskaia, E A; Dmitriev, B A

    1985-07-01

    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.

  16. Antitumor polysaccharides from mushrooms: a review on the structural characteristics, antitumor mechanisms and immunomodulating activities.

    PubMed

    Meng, Xin; Liang, Hebin; Luo, Lixin

    2016-04-07

    Mushrooms are popular folk medicines that have attracted considerable attention because of their efficient antitumor activities. This review covers existing research achievements on the mechanisms of isolated mushroom polysaccharides, particularly (1→3)-β-D-glucans. Our review also describes the function in modulating the immune system and potential tumor-inhibitory effects of polysaccharides. The antitumor mechanisms of mushroom polysaccharides are mediated by stimulated T cells or other immune cells. These polysaccharides are able to trigger various cellular responses, such as the expression of cytokines and nitric oxide. Most polysaccharides could bind other conjugate molecules, such as polypeptides and proteins, whose conjugation always possess strong antitumor activities. The purpose of this review is to summarize available information, and to reflect the present situation of polysaccharide research filed with a view for future direction.

  17. Pivotal Roles of the Outer Membrane Polysaccharide Export and Polysaccharide Copolymerase Protein Families in Export of Extracellular Polysaccharides in Gram-Negative Bacteria

    PubMed Central

    Cuthbertson, Leslie; Mainprize, Iain L.; Naismith, James H.; Whitfield, Chris

    2009-01-01

    Summary: Many bacteria export extracellular polysaccharides (EPS) and capsular polysaccharides (CPS). These polymers exhibit remarkably diverse structures and play important roles in the biology of free-living, commensal, and pathogenic bacteria. EPS and CPS production represents a major challenge because these high-molecular-weight hydrophilic polymers must be assembled and exported in a process spanning the envelope, without compromising the essential barrier properties of the envelope. Emerging evidence points to the existence of molecular scaffolds that perform these critical polymer-trafficking functions. Two major pathways with different polymer biosynthesis strategies are involved in the assembly of most EPS/CPS: the Wzy-dependent and ATP-binding cassette (ABC) transporter-dependent pathways. They converge in an outer membrane export step mediated by a member of the outer membrane auxiliary (OMA) protein family. OMA proteins form outer membrane efflux channels for the polymers, and here we propose the revised name outer membrane polysaccharide export (OPX) proteins. Proteins in the polysaccharide copolymerase (PCP) family have been implicated in several aspects of polymer biogenesis, but there is unequivocal evidence for some systems that PCP and OPX proteins interact to form a trans-envelope scaffold for polymer export. Understanding of the precise functions of the OPX and PCP proteins has been advanced by recent findings from biochemistry and structural biology approaches and by parallel studies of other macromolecular trafficking events. Phylogenetic analyses reported here also contribute important new insight into the distribution, structural relationships, and function of the OPX and PCP proteins. This review is intended as an update on progress in this important area of microbial cell biology. PMID:19258536

  18. Structural Investigation of Cell Wall Xylan Polysaccharides from the Leaves of Algerian Argania spinosa.

    PubMed

    Hachem, Kadda; Faugeron, Céline; Kaid-Harche, Meriem; Gloaguen, Vincent

    2016-11-21

    Xylan-type polysaccharides were isolated from the leaves of Argania spinosa (L.) Skeels collected in the Tindouf area (southwestern Algeria). Xylan fractions were obtained by sequential alkaline extractions and purified on Sepharose CL-4B. The xylan structure was investigated by enzymatic hydrolysis with an endo-β(1→4)-xylanase followed by chromatography of the resulting fragments on Biogel P2, characterization by sugar analysis and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS ). The results show that the A. spinosa xylan is composed of a β-(1→4)-d-xylopyranose backbone substituted with 4-O-methyl-d-glucuronic acid and L-arabinose residues.

  19. Diatom-Specific Oligosaccharide and Polysaccharide Structures Help to Unravel Biosynthetic Capabilities in Diatoms

    PubMed Central

    Gügi, Bruno; Le Costaouec, Tinaïg; Burel, Carole; Lerouge, Patrice; Helbert, William; Bardor, Muriel

    2015-01-01

    Diatoms are marine organisms that represent one of the most important sources of biomass in the ocean, accounting for about 40% of marine primary production, and in the biosphere, contributing up to 20% of global CO2 fixation. There has been a recent surge in developing the use of diatoms as a source of bioactive compounds in the food and cosmetic industries. In addition, the potential of diatoms such as Phaeodactylum tricornutum as cell factories for the production of biopharmaceuticals is currently under evaluation. These biotechnological applications require a comprehensive understanding of the sugar biosynthesis pathways that operate in diatoms. Here, we review diatom glycan and polysaccharide structures, thus revealing their sugar biosynthesis capabilities. PMID:26393622

  20. Structure and Antitumor and Immunomodulatory Activities of a Water-Soluble Polysaccharide from Dimocarpus longan Pulp

    PubMed Central

    Meng, Fa-Yan; Ning, Yuan-Ling; Qi, Jia; He, Zhou; Jie, Jiang; Lin, Juan-Juan; Huang, Yan-Jun; Li, Fu-Sen; Li, Xue-Hua

    2014-01-01

    A new water-soluble polysaccharide (longan polysaccharide 1 (LP1)) was extracted and successfully purified from Dimocarpus longan pulp via diethylaminoethyl (DEAE)-cellulose anion-exchange and Sephacryl S-300 HR gel chromatography. The chemical structure was determined using Infrared (IR), gas chromatography (GC) and nuclear magnetic resonance (NMR) analysis. The results indicated that the molecular weight of the sample was 1.1 × 105 Da. Monosaccharide composition analysis revealed that LP1 was composed of Glc, GalA, Ara and Gal in a molar ratio of 5.39:1.04:0.74:0.21. Structural analysis indicated that LP1 consisted of a backbone of →4)-α-d-Glcp-(1→4)-α-d-GalpA-(1→4)-α-d-Glcp-(1→4)-β-d-Glcp-(1→ units with poly saccharide side chains composed of →2)-β-d-Fruf-(1→2)-l-sorbose-(1→ attached to the O-6 position of the α-d-Glcp residues. In vitro experiments indicated that LP1 had significantly high antitumor activity against SKOV3 and HO8910 tumor cells, with inhibition percentages of 40% and 50%, respectively. In addition, LP1 significantly stimulated the production of the cytokine interferon-γ (IFN-γ), increased the activity of murine macrophages and enhanced B- and T-lymphocyte proliferation. The results of this study demonstrate that LP1 has potential applications as a natural antitumor agent with immunomodulatory activity. PMID:24663085

  1. Structural correlates of carrier protein recognition in tetanus toxoid-conjugated bacterial polysaccharide vaccines

    PubMed Central

    Lockyer, Kay; Gao, Fang; Derrick, Jeremy P.; Bolgiano, Barbara

    2015-01-01

    An analysis of structure-antibody recognition relationships in nine licenced polysaccharide-tetanus toxoid (TT) conjugate vaccines was performed. The panel of conjugates used included vaccine components to protect against disease caused by Haemophilus influenzae type b, Neisseria meningitidis groups A, C, W and Y and Streptococcus pneumoniae serotype 18C. Conformation and structural analysis included size exclusion chromatography with multi-angle light scattering to determine size, and intrinsic fluorescence spectroscopy and fluorescence quenching to evaluate the protein folding and exposure of Trp residues. A capture ELISA measured the recognition of TT epitopes in the conjugates, using four rat monoclonal antibodies: 2 localised to the HC domain, and 2 of which were holotoxoid conformation-dependent. The conjugates had a wide range of average molecular masses ranging from 1.8 × 106 g/mol to larger than 20 × 106 g/mol. The panel of conjugates were found to be well folded, and did not have spectral features typical of aggregated TT. A partial correlation was found between molecular mass and epitope recognition. Recognition of the epitopes either on the HC domain or the whole toxoid was not necessarily hampered by the size of the molecule. Correlation was also found between the accessibility of Trp side chains and polysaccharide loading, suggesting also that a higher level of conjugated PS does not necessarily interfere with toxoid accessibility. There were different levels of carrier protein Trp side-chain and epitope accessibility that were localised to the HC domain; these were related to the saccharide type, despite the conjugates being independently manufactured. These findings extend our understanding of the molecular basis for carrier protein recognition in TT conjugate vaccines. PMID:25640334

  2. Quaternary structure of WzzB and WzzE polysaccharide copolymerases

    PubMed Central

    Kalynych, Sergei; Cherney, Maia; Bostina, Mihnea; Rouiller, Isabelle; Cygler, Miroslaw

    2015-01-01

    Bacteria have evolved cellular control mechanisms to ensure proper length specification for surface-bound polysaccharides. Members of the Polysaccharide Copolymerase (PCP) family are central to this process. PCP-1 family members are anchored to the inner membrane through two transmembrane helices and contain a large periplasm-exposed domain. PCPs are known to form homooligomers but their exact stoichiometry is controversial in view of conflicting structural and biochemical data. Several prior investigations addressing this question indicated a nonameric, hexameric, or tetrameric organization of several PCP-1 family members. In this work, we gathered additional evidence that E.coli WzzB and WzzE PCPs form octameric homo-oligomeric complexes. Detergent-solubilized PCPs were purified to homogeneity and subjected to blue native gel analysis, which indicated the presence of a predominant high-molecular product of over 500 kDa in mass. Molecular mass of WzzE and WzzB-detergent oligomers was estimated to be 550 kDA by size-exclusion coupled to multiangle laser light scattering (SEC-MALLS). Oligomeric organization of purified WzzB and WzzE was further investigated by negative stain electron microscopy and by X-ray crystallography, respectively. Analysis of EM-derived molecular envelope of WzzB indicated that the full-length protein is composed of eight protomers. Crystal structure of LDAO-solubilized WzzE was solved to 6 Å resolutions and revealed its octameric subunit stoichiometry. In summary, we identified a possible biological unit utilized for the glycan chain length determination by two PCP-1 family members. This provides an important step toward further unraveling of the mechanistic basis of chain length control of the O-antigen and the enterobacterial common antigen. PMID:25307743

  3. Structural correlates of carrier protein recognition in tetanus toxoid-conjugated bacterial polysaccharide vaccines.

    PubMed

    Lockyer, Kay; Gao, Fang; Derrick, Jeremy P; Bolgiano, Barbara

    2015-03-10

    An analysis of structure-antibody recognition relationships in nine licenced polysaccharide-tetanus toxoid (TT) conjugate vaccines was performed. The panel of conjugates used included vaccine components to protect against disease caused by Haemophilus influenzae type b, Neisseria meningitidis groups A, C, W and Y and Streptococcus pneumoniae serotype 18C. Conformation and structural analysis included size exclusion chromatography with multi-angle light scattering to determine size, and intrinsic fluorescence spectroscopy and fluorescence quenching to evaluate the protein folding and exposure of Trp residues. A capture ELISA measured the recognition of TT epitopes in the conjugates, using four rat monoclonal antibodies: 2 localised to the HC domain, and 2 of which were holotoxoid conformation-dependent. The conjugates had a wide range of average molecular masses ranging from 1.8×10(6) g/mol to larger than 20×10(6) g/mol. The panel of conjugates were found to be well folded, and did not have spectral features typical of aggregated TT. A partial correlation was found between molecular mass and epitope recognition. Recognition of the epitopes either on the HC domain or the whole toxoid was not necessarily hampered by the size of the molecule. Correlation was also found between the accessibility of Trp side chains and polysaccharide loading, suggesting also that a higher level of conjugated PS does not necessarily interfere with toxoid accessibility. There were different levels of carrier protein Trp side-chain and epitope accessibility that were localised to the HC domain; these were related to the saccharide type, despite the conjugates being independently manufactured. These findings extend our understanding of the molecular basis for carrier protein recognition in TT conjugate vaccines.

  4. Agrobacterium rubi(T) DSM 6772 produces a lipophilic polysaccharide capsule whose degree of acetylation is growth modulated.

    PubMed

    De Castro, Cristina; Gargiulo, Valentina; Lanzetta, Rosa; Parrilli, Michelangelo

    2007-03-01

    The structure of the capsular polysaccharide produced from the type strain of Agrobacterium rubi DSM 6772 is demonstrated by means of chemical and spectroscopical methodologies. It is constituted from the quite rare monosaccharide 6-deoxy-L-talose, involved in alternating alpha-(1 --> 2) and alpha-(1 --> 3) linkages. This simple backbone is further complicated from the occurrence of O-acetyl substituents located always at O-2 of the O-3 substituted 6-deoxy-talose. This decoration is not stoichiometric and it depends on the growth stadium of the bacterium, leading to an almost regular acetylation pattern only at the stationary phase, where all the potential positions are substituted.

  5. Structural Characterization and Antifatigue Effect In Vivo of Maca (Lepidium meyenii Walp) Polysaccharide.

    PubMed

    Tang, Weimin; Jin, Lu; Xie, Lianghua; Huang, Juqing; Wang, Nan; Chu, Bingquan; Dai, Xulin; Liu, Yu; Wang, Rui; Zhang, Ying

    2017-03-01

    Maca (Lepidium meyenii Walp) polysaccharides (MP) with purity of 99.2% were obtained to investigate their structural characteristics and antifatigue effect in vivo. The physicochemical properties of MP were analyzed through high-performance gel filtration chromatography, IR, monosaccharide composition, methylation, GC-MS, and NMR analyses. The antifatigue effect of MP was evaluated by using a mouse weight-loaded swimming model. MP is an acidic heteropolysaccharide with an average molecular weight (Mw ) of 793.5 kDa. It is composed of D-GalA: D-Glc: L-Ara: D-Man: D-Gal: L-Rha = 35.07:29.98:16.98:13.01:4.21:0.75 (mol, %). The findings revealed that MP contained β-1,3-Galp(A), β-1,3-Glcp, and α-1, 3-Manp linked alternatingly to form a backbone (5:4:1). MP (above mid-dosage 50 mg/kg bw/d) could effectively elongate swimming durations and accelerate average swimming speeds (within the 1st 5 min) of mice (P < 0.05) and improve the serous biochemical parameters of mice. Compared with the control model, high-dosage (100 mg/kg bw/d) MP treatment could significantly enhance glutathione peroxidase and creatine kinase activities (P < 0.05) and decreased lactate dehydrogenase activity (P < 0.01). High-dosage MP could significantly reduce the levels of blood urea nitrogen, lactic acid, and malondialdehyde (P < 0.05). MP is an acidic polysaccharide with a high D-GalA content, which could be responsible for the antifatigue effect of maca.

  6. Antibiotic modulation of capsular exopolysaccharide and virulence in Acinetobacter baumannii.

    PubMed

    Geisinger, Edward; Isberg, Ralph R

    2015-02-01

    Acinetobacter baumannii is an opportunistic pathogen of increasing importance due to its propensity for intractable multidrug-resistant infections in hospitals. All clinical isolates examined contain a conserved gene cluster, the K locus, which determines the production of complex polysaccharides, including an exopolysaccharide capsule known to protect against killing by host serum and to increase virulence in animal models of infection. Whether the polysaccharides determined by the K locus contribute to intrinsic defenses against antibiotics is unknown. We demonstrate here that mutants deficient in the exopolysaccharide capsule have lowered intrinsic resistance to peptide antibiotics, while a mutation affecting sugar precursors involved in both capsule and lipopolysaccharide synthesis sensitizes the bacterium to multiple antibiotic classes. We observed that, when grown in the presence of certain antibiotics below their MIC, including the translation inhibitors chloramphenicol and erythromycin, A. baumannii increases production of the K locus exopolysaccharide. Hyperproduction of capsular exopolysaccharide is reversible and non-mutational, and occurs concomitantly with increased resistance to the inducing antibiotic that is independent of the presence of the K locus. Strikingly, antibiotic-enhanced capsular exopolysaccharide production confers increased resistance to killing by host complement and increases virulence in a mouse model of systemic infection. Finally, we show that augmented capsule production upon antibiotic exposure is facilitated by transcriptional increases in K locus gene expression that are dependent on a two-component regulatory system, bfmRS. These studies reveal that the synthesis of capsule, a major pathogenicity determinant, is regulated in response to antibiotic stress. Our data are consistent with a model in which gene expression changes triggered by ineffectual antibiotic treatment cause A. baumannii to transition between states of low

  7. Antibiotic Modulation of Capsular Exopolysaccharide and Virulence in Acinetobacter baumannii

    PubMed Central

    Geisinger, Edward; Isberg, Ralph R.

    2015-01-01

    Acinetobacter baumannii is an opportunistic pathogen of increasing importance due to its propensity for intractable multidrug-resistant infections in hospitals. All clinical isolates examined contain a conserved gene cluster, the K locus, which determines the production of complex polysaccharides, including an exopolysaccharide capsule known to protect against killing by host serum and to increase virulence in animal models of infection. Whether the polysaccharides determined by the K locus contribute to intrinsic defenses against antibiotics is unknown. We demonstrate here that mutants deficient in the exopolysaccharide capsule have lowered intrinsic resistance to peptide antibiotics, while a mutation affecting sugar precursors involved in both capsule and lipopolysaccharide synthesis sensitizes the bacterium to multiple antibiotic classes. We observed that, when grown in the presence of certain antibiotics below their MIC, including the translation inhibitors chloramphenicol and erythromycin, A. baumannii increases production of the K locus exopolysaccharide. Hyperproduction of capsular exopolysaccharide is reversible and non-mutational, and occurs concomitantly with increased resistance to the inducing antibiotic that is independent of the presence of the K locus. Strikingly, antibiotic-enhanced capsular exopolysaccharide production confers increased resistance to killing by host complement and increases virulence in a mouse model of systemic infection. Finally, we show that augmented capsule production upon antibiotic exposure is facilitated by transcriptional increases in K locus gene expression that are dependent on a two-component regulatory system, bfmRS. These studies reveal that the synthesis of capsule, a major pathogenicity determinant, is regulated in response to antibiotic stress. Our data are consistent with a model in which gene expression changes triggered by ineffectual antibiotic treatment cause A. baumannii to transition between states of low

  8. Structure of a Bacterial ABC Transporter Involved in the Import of an Acidic Polysaccharide Alginate.

    PubMed

    Maruyama, Yukie; Itoh, Takafumi; Kaneko, Ai; Nishitani, Yu; Mikami, Bunzo; Hashimoto, Wataru; Murata, Kousaku

    2015-09-01

    The acidic polysaccharide alginate represents a promising marine biomass for the microbial production of biofuels, although the molecular and structural characteristics of alginate transporters remain to be clarified. In Sphingomonas sp. A1, the ATP-binding cassette transporter AlgM1M2SS is responsible for the import of alginate across the cytoplasmic membrane. Here, we present the substrate-transport characteristics and quaternary structure of AlgM1M2SS. The addition of poly- or oligoalginate enhanced the ATPase activity of reconstituted AlgM1M2SS coupled with one of the periplasmic solute-binding proteins, AlgQ1 or AlgQ2. External fluorescence-labeled oligoalginates were specifically imported into AlgM1M2SS-containing proteoliposomes in the presence of AlgQ2, ATP, and Mg(2+). The crystal structure of AlgQ2-bound AlgM1M2SS adopts an inward-facing conformation. The interaction between AlgQ2 and AlgM1M2SS induces the formation of an alginate-binding tunnel-like structure accessible to the solvent. The translocation route inside the transmembrane domains contains charged residues suitable for the import of acidic saccharides.

  9. POLYS 2.0: An open source software package for building three-dimensional structures of polysaccharides.

    PubMed

    Engelsen, Søren B; Hansen, Peter I; Pérez, Serge

    2014-07-01

    This article describes an update of POLYS, the POLYSaccharide builder, for generating three-dimensional structures of polysaccharides and complex carbohydrates (Engelsen et al., Biopolymers 1996, 39, 417-433). POLYS is written in portable ANSI C and is now released under an open source license. Using this software, complex branched carbohydrate structures and polysaccharides can be constructed from their primary structure and the relevant monosaccharides stored in database containing information on optimized glycosidic linkage geometries. The constructed three-dimensional structures are described as Cartesian coordinate files which can be used as input to other molecular modeling software. The new version of POLYS includes a large database of monosaccharides and a helical generator to build and optimize regular single helix or double helix structures. To demonstrate the efficiency of POLYS to build carbohydrate structures, four examples of increasing complexity are presented in the manuscript, from simple alpha glucans over complex starch fragments and the double helical structure of amylopectin to the mega-oligosaccharide RhamnoGalacturonan II.

  10. Structure of the O-antigen of Vibrio cholerae O155 that shares a putative D-galactose 4,6-cyclophosphate-associated epitope with V. cholerae O139 Bengal.

    PubMed

    Senchenkova, S N; Zatonsky, G V; Shashkov, A S; Knirel, Y A; Jansson, P E; Weintraub, A; Albert, M J

    1998-05-15

    The O-specific polysaccharide of Vibrio cholerae 0155 was studied by sugar and methylation analyses, dephosphorylation with 48% hydrofluoric acid, 1H- and 13C-NMR spectroscopy, including two-dimensional COSY, TOCSY, NOESY, and heteronuclear single-quantum coherence (HSQC) experiments. The following structure of the pentasaccharide repeating unit of the polysaccharide was established: carbohydrate sequence [see text]. An unusual component, D-galactose 4,6-cyclophosphate, has been reported previously as a component of the capsular polysaccharide and O-antigen of V. cholerae O139 Bengal and appears to be responsible for the known serological cross-reactivity between V. cholerae O139 and O155.

  11. Complete structure of the cell surface polysaccharide of Streptococcus oralis C104: A 600-MHz NMR study

    SciTech Connect

    Abeygunawardana, C.; Bush, C.A. ); Cisar, J.O. )

    1991-09-03

    Specific lectin-carbohydrate interactions between certain oral streptococci and actinomyces contribute to the microbial colonization of teeth. The receptor molecules of Streptococcus oralis, 34, ATCC 10557, and Streptococcus mitis J22 for the galactose and N-acetylgalactosamine reactive fimbrial lectins of Actinomyces viscosus and Actinomyces naeslundii are antigenically distinct polysaccharides, each formed by a different phosphodiester-linked oligosaccharide repeating unit. Receptor polysaccharide was isolated form S. oralis C104 cells and was shown to contain galactose, N-acetylgalactosamine, ribitol, and phosphate with molar ratios of 4:1:1:1. The {sup 1}H NMR spectrum of the polysaccharide shows that it contains a repeating structure. The individual sugars in the repeating unit were identified by {sup 1}H coupling constants observed in E-COSY and DQF-COSY spectra. NMR methods included complete resonance assignments ({sup 1}H and {sup 13}C) by various homonuclear and heteronuclear correlation experiments that utilize scalar couplings. Sequence and linkage assignments were obtained from the heteronuclear multiple-bond correlation (HMBC) spectrum. This analysis shows that the receptor polysaccharide of S. oralis C104 is a ribitol teichoic acid polymer composed of a linear hexasaccharide repeating unit containing two residues each of galactopyranose and galactofuranose and a residue each of GalNAc and ribitol joined end to end by phosphodiester linkages.

  12. Effects of extraction methods on the yield, chemical structure and anti-tumor activity of polysaccharides from Cordyceps gunnii mycelia.

    PubMed

    Zhu, Zhen-Yuan; Dong, Fengying; Liu, Xiaocui; Lv, Qian; YingYang; Liu, Fei; Chen, Ling; Wang, Tiantian; Wang, Zheng; Zhang, Yongmin

    2016-04-20

    This study was to investigate the effects of different extraction methods on the yield, chemical structure and antitumor activity of polysaccharides from Cordyceps gunnii (C. gunnii) mycelia. Five extraction methods were used to extract crude polysaccharides (CPS), which include room-temperature water extraction (RWE), hot-water extraction (HWE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and cellulase-assisted extraction (CAE). Then Sephadex G-100 was used for purification of CPS. As a result, the antitumor activities of CPS and PPS on S180 cells were evaluated. Five CPS and purified polysaccharides (PPS) were obtained. The yield of CPS by microwave-assisted extraction (CPSMAE) was the highest and its anti-tumor activity was the best and its macromolecular polysaccharide (3000-1000kDa) ratio was the largest. The PPS had the same monosaccharide composition, but their obvious difference was in the antitumor activity and the physicochemical characteristics, such as intrinsic viscosity, specific rotation, scanning electron microscopy and circular dichroism spectra.

  13. Biosynthesis of the Pseudomonas aeruginosa Extracellular Polysaccharides, Alginate, Pel, and Psl

    PubMed Central

    Franklin, Michael J.; Nivens, David E.; Weadge, Joel T.; Howell, P. Lynne

    2011-01-01

    Pseudomonas aeruginosa thrives in many aqueous environments and is an opportunistic pathogen that can cause both acute and chronic infections. Environmental conditions and host defenses cause differing stresses on the bacteria, and to survive in vastly different environments, P. aeruginosa must be able to adapt to its surroundings. One strategy for bacterial adaptation is to self-encapsulate with matrix material, primarily composed of secreted extracellular polysaccharides. P. aeruginosa has the genetic capacity to produce at least three secreted polysaccharides; alginate, Psl, and Pel. These polysaccharides differ in chemical structure and in their biosynthetic mechanisms. Since alginate is often associated with chronic pulmonary infections, its biosynthetic pathway is the best characterized. However, alginate is only produced by a subset of P. aeruginosa strains. Most environmental and other clinical isolates secrete either Pel or Psl. Little information is available on the biosynthesis of these polysaccharides. Here, we review the literature on the alginate biosynthetic pathway, with emphasis on recent findings describing the structure of alginate biosynthetic proteins. This information combined with the characterization of the domain architecture of proteins encoded on the Psl and Pel operons allowed us to make predictive models for the biosynthesis of these two polysaccharides. The results indicate that alginate and Pel share certain features, including some biosynthetic proteins with structurally or functionally similar properties. In contrast, Psl biosynthesis resembles the EPS/CPS capsular biosynthesis pathway of Escherichia coli, where the Psl pentameric subunits are assembled in association with an isoprenoid lipid carrier. These models and the environmental cues that cause the cells to produce predominantly one polysaccharide over the others are subjects of current investigation. PMID:21991261

  14. Pseudomonas aeruginosa inactivation mechanism is affected by capsular extracellular polymeric substances reactivity with chlorine and monochloramine.

    PubMed

    Xue, Zheng; Hessler, Christopher M; Panmanee, Warunya; Hassett, Daniel J; Seo, Youngwoo

    2013-01-01

    The reactivity of capsular extracellular polymeric substances (EPS) to chlorine and monochloramine was assessed and compared in this study. The impact of capsular EPS on Gram-negative bacteria Pseudomonas aeruginosa inactivation mechanisms was investigated both qualitatively and quantitatively using a combination of batch experiments, viability tests with LIVE/DEAD staining, and Fourier transform infrared spectroscopy (FTIR). Both wild-type and isogenic mutant strains with different alginate EPS production capabilities were used to evaluate their susceptibility to chlorine and monochloramine. The mucA22 mutant strain, which overproduces the EPS composed largely of acidic polysaccharide alginate, exhibited high resistance and prolonged inactivation time to both chlorine and monochloramine relative to PAO1 (wild-type) and algT(U) mutant strains (alginate EPS deficient). Multiple analyses were combined to better understand the mechanistic role of EPS against chlorine-based disinfectants. The extracted EPS exhibited high reactivity with chlorine and very low reactivity with monochloramine, suggesting different mechanism of protection against disinfectants. Moreover, capsular EPS on cell membrane appeared to reduce membrane permeabilization by disinfectants as suggested by deformation of key functional groups in EPS and cell membrane (the C-O-C stretching of carbohydrate and the C=O stretching of ester group). The combined results supported that capsular EPS, acting either as a disinfectant consumer (for chlorine inactivation) or limiting access to reactive sites on cell membrane (for monochloramine inactivation), provide a protective role for bacterial cells against regulatory residual disinfectants by reducing membrane permeabilization.

  15. Molecular dimensions and structural features of neutral polysaccharides from the seed mucilage of Hyptis suaveolens L.

    PubMed

    Praznik, Werner; Čavarkapa, Andrea; Unger, Frank M; Loeppert, Renate; Holzer, Wolfgang; Viernstein, Helmut; Mueller, Monika

    2017-04-15

    The seed mucilage of Hyptis suaveolens L. includes acid - and neutral heteropolysaccharides in a ratio of about 1:1. The anionic charged fraction responsible for swelling and viscous behaviour possesses an average molar mass of Mw=350kg/mol, Mn=255kg/mol. The neutral polysaccharide fraction shows an average molar mass of Mw=47kg/mol and Mn=28kg/mol and is composed of d-Galp-, d-Glcp- and d-Manp residues in a molar ratio of about 3:2:1. The structural features present galactoglucan (30%) and galactoglucomannan (70%) with a high level of terminal β-linked d-Galp residues (18%). Structural details of galactoglucomannan are derived by combined enzymatic and chemical methods as well as NMR spectroscopy. Sequences of octa/nonasaccharide β-d-Glcp-(1→4)[β-d-Galp-(1→2)-α-d-Galp-(1→6)]-β-d-Manp-(1→4)-β-d-Glcp-(1→4)-β-d-Glcp-(1→4)[β-d-Galp-(1→2)-α-d-Galp-(1→6)]-β-d-Manp and lower mass tetrasaccharide repeating units β-d-Glcp-(1→4)[β-d-Galp-(1→2)-α-d-Galp-(1→6)]-β-d-Manp were found. The level of the prebiotic activity is related to the availability of β-linked d-Galp residues in the side chains of the molecules.

  16. Characterization of a bioactive polysaccharide from Ganoderma atrum: Re-elucidation of the fine structure.

    PubMed

    Zhang, Hui; Nie, Shaoping; Cui, Steve W; Xu, Ming; Ding, Huihuang; Xie, Mingyong

    2017-02-20

    The fine structure in terms of backbone and branch chain features of a bioactive polysaccharide from Ganoderma atrum (PSG-1) was re-elucidated systematically using high performance anion-exchange chromatography (HPAEC), methylation and GLC-MS analysis, and 1D & 2D NMR spectroscopy. Monosaccharide composition analysis revealed that PSG-1-F0.2 fraction mainly consisted of glucose (73.8%) and glucuronic acid (15.3%), with small amount of mannose (5.7%) and galactose (5.2%). Based on methylation, multistep partial acid hydrolysis and NMR study, were proposed to substitute at the O-6 position of β-(1→3)-glucan. The small amount of mannose and galactose residues were considered to be from the other fraction in PSG which was very difficult to be separated from PSG-1-F0.2. This revised structure as an acidic β-(1→3, 1→6)-glucan is considered to be more accurate than the previous proposal of PSG-1.

  17. Structural Characterization of a Water-Soluble Polysaccharide from the Fruiting Bodies of Agaricus bisporus

    PubMed Central

    He, Jinzhe; Zhang, Anqiang; Ru, Qiaomei; Dong, Dandan; Sun, Peilong

    2014-01-01

    An edible fungal polysaccharide termed as ABP was obtained by extraction with hot water, and followed successive chromatographic purification using DEAE-Sepharose Fast Flow column and Sephacryl S-300 High-Resolution column. A symmetrical peak was obtained on high-performance size-exclusion chromatography with an average molecular weight of 5.17 × 104 Da, which was named ABP, and its main components were d-glucose and d-mannose. Based on the study of methylation analysis, along with FT-IR, GC, GC-MS, 1D 1H and 13C NMR and 2D NMR (H-HCOSY, TOCSY, HMQC, and NOESY), its chemical structure was featured with a repeating unit (1→6) linking β-d-Glcp as the main backbone with (1→4)-linked α-d-Manp units. The structure of the mainly repeating units of ABP was established as: →6)-β-D-Glucp-(1→4)-α-D-Manp(1→6)-β-D-Glucp-(1→6)-β-D-Glucp-(1→ PMID:24406732

  18. Serogroup quantitation of multivalent polysaccharide and polysaccharide-conjugate meningococcal vaccines from China.

    PubMed

    Cook, Matthew C; Gibeault, Sabrina; Filippenko, Vasilisa; Ye, Qiang; Wang, Junzhi; Kunkel, Jeremy P

    2013-07-01

    The active components of most meningococcal vaccines are four antigenic serogroup capsular polysaccharides (A, C, Y, W135). The vaccines, monovalent or multivalent mixtures of either free polysaccharides or polysaccharides conjugated to antigenic carrier proteins, may be in liquid or lyophilised formulations, with or without excipients. Acid hydrolysis and chromatographic methods for serogroup quantitation, which were previously optimised and qualified using polysaccharide-based standards and a narrow range of real vaccines, are here challenged with multiple lots of a broad assortment of additional multivalent polysaccharide-based meningococcal vaccine products. Centrifugal filtration successfully removed all interfering lactose excipient without loss of polysaccharides to allow for the determination of Y and W135 serogroups. Replicate operations by three different analysts indicated high method reproducibility. Results indicated some lot-to-lot and product-to-product variations. However, all vaccines were within general specifications for each serogroup polysaccharide, with the exception of all lots of one polysaccharide vaccine - which by these methods were found to be deficient in the serogroup A component only. These robust techniques are very useful for the evaluation of antigen content and consistency of manufacture. The deformulation, hydrolysis and chromatographic methods may be adaptable for the evaluation of other types of polysaccharide-based vaccines.

  19. An OMV Vaccine Derived from a Capsular Group B Meningococcus with Constitutive FetA Expression: Preclinical Evaluation of Immunogenicity and Toxicity

    PubMed Central

    Norheim, Gunnstein; Sanders, Holly; Mellesdal, Jardar W.; Sundfør, Idunn; Chan, Hannah; Brehony, Carina; Vipond, Caroline; Dold, Chris; Care, Rory; Saleem, Muhammad; Maiden, Martin C. J.; Derrick, Jeremy P.; Feavers, Ian; Pollard, Andrew J.

    2015-01-01

    Following the introduction of effective protein-polysaccharide conjugate vaccines against capsular group C meningococcal disease in Europe, meningococci of capsular group B remain a major cause of death and can result in debilitating sequelae. The outer membrane proteins PorA and FetA have previously been shown to induce bactericidal antibodies in humans. Despite considerable antigenic variation among PorA and FetA OMPs in meningococci, systematic molecular epidemiological studies revealed this variation is highly structured so that a limited repertoire of antigenic types is congruent with the hyperinvasive meningococcal lineages that have caused most of the meningococcal disease in Europe in recent decades. Here we describe the development of a prototype vaccine against capsular group B meningococcal infection based on a N. meningitidis isolate genetically engineered to have constitutive expression of the outer membrane protein FetA. Deoxycholate outer membrane vesicles (dOMVs) extracted from cells cultivated in modified Frantz medium contained 21.8% PorA protein, 7.7% FetA protein and 0.03 μg LPS per μg protein (3%). The antibody response to the vaccine was tested in three mouse strains and the toxicological profile of the vaccine was tested in New Zealand white rabbits. Administration of the vaccine, MenPF-1, when given by intramuscular injection on 4 occasions over a 9 week period, was well tolerated in rabbits up to 50 μg/dose, with no evidence of systemic toxicity. These data indicated that the MenPF-1 vaccine had a toxicological profile suitable for testing in a phase I clinical trial. PMID:26390123

  20. Structural features of a water soluble gum polysaccharide from Murraya paniculata fruits.

    PubMed

    Mondal, S K; Ray, B; Ghosal, P K; Teleman, A; Vuorinen, T

    2001-10-22

    A water soluble gum polysaccharide was isolated from Murraya paniculata fruits. Hydrolytic experiments, methylation analysis, periodate oxidation studies and NMR data revealed that the polysaccharide was extensively branched and it consisted of 1,3-, and 1,3,6-linked beta-D-galactopyranosyl units, terminal beta-D-galactopyranosyl units and terminal alpha-D-glucopyranosyl 1,4-beta-D-galactopyranosyl units. Small amounts of 4-O-methylglucuronic acid residues were also present.

  1. The Role of Bacterial Protein Tyrosine Phosphatases in the Regulation of the Biosynthesis of Secreted Polysaccharides

    PubMed Central

    Morona, Renato

    2014-01-01

    Abstract Significance: Tyrosine phosphorylation and associated protein tyrosine phosphatases are gaining prominence as critical mechanisms in the regulation of fundamental processes in a wide variety of bacteria. In particular, these phosphatases have been associated with the control of the biosynthesis of capsular polysaccharides and extracellular polysaccharides, critically important virulence factors for bacteria. Recent Advances: Deletion and overexpression of the phosphatases result in altered polysaccharide biosynthesis in a range of bacteria. The recent structures of associated auto-phosphorylating tyrosine kinases have suggested that the phosphatases may be critical for the cycling of the kinases between monomers and higher order oligomers. Critical Issues: Additional substrates of the phosphatases apart from cognate kinases are currently being identified. These are likely to be critical to our understanding of the mechanism by which polysaccharide biosynthesis is regulated. Future Directions: Ultimately, these protein tyrosine phosphatases are an attractive target for the development of novel antimicrobials. This is particularly the case for the polymerase and histidinol phosphatase family, which is predominantly found in bacteria. Furthermore, the determination of bacterial tyrosine phosphoproteomes will likely help to uncover the fundamental roles, mechanism, and critical importance of these phosphatases in a wide range of bacteria. Antioxid. Redox Signal. 20, 2274–2289. PMID:24295407

  2. Streptococcus iniae cpsG alters capsular carbohydrate composition and is a cause of serotype switching in vaccinated fish.

    PubMed

    Heath, Candice; Gillen, Christine M; Chrysanthopoulos, Panagiotis; Walker, Mark J; Barnes, Andrew C

    2016-09-25

    Streptococcus iniae causes septicaemia and meningitis in marine and freshwater fish wherever they are farmed in warm-temperate and tropical regions. Although serotype specific, vaccination with bacterins (killed bacterial cultures) is largely successful and vaccine failure occurs only occasionally through emergence of new capsular serotypes. Previously we showed that mutations in vaccine escapes are restricted to a limited repertoire of genes within the 20-gene capsular polysaccharide (cps) operon. cpsG, a putative UDP-galactose 4-epimerase, has three sequence types based on the insertion or deletion of the three amino acids leucine, serine and lysine in the substrate binding site of the protein. To elucidate the role of cpsG in capsular polysaccharide (CPS) biosynthesis and capsular composition, we first prepared isogenic knockout and complemented mutants of cpsG by allelic exchange mutagenesis. Deletion of cpsG resulted in changes to colony morphology and cell buoyant density, and also significantly decreased galactose content relative to glucose in the capsular polysaccharide as determined by GC-MS, consistent with epimerase activity of CpsG. There was also a metabolic penalty of cpsG knockout revealed by slower growth in complex media, and reduced proliferation in whole fish blood. Moreover, whilst antibodies raised in fish against the wild type cross-reacted in whole cell and cps ELISA, they did not cross-opsonise the mutant in a peripheral blood neutrophil opsonisation assay, consistent with reported vaccine escape. We have shown here that mutation in cpsG results in altered CPS composition and this in turn results in poor cross-opsonisation that explains some of the historic vaccination failure on fish farms in Australia.

  3. Computer-assisted analysis of the structure of regular branched polysaccharides containing 2,3-disubstituted rhamnopyranose and mannopyranose residues on the basis of 13C NMR data.

    PubMed

    Lipkind, G M; Shashkov, A S; Nifant'ev, N E; Kochetkov, N K

    1992-12-31

    A computer-assisted approach to the analysis of the structure of branched polysaccharides that contain 2,3-di-O-glycosylated alpha-rhamnopyranose and alpha-mannopyranose residues is based on evaluation of the 13C NMR spectra, using glycosylation effects and their deviations from additivity (delta delta values) at the branch points. This approach, in combination with monosaccharide and methylation analysis data, has been verified on a series of bacterial polysaccharides of known structure.

  4. Unusual structures in the polysaccharides from the red seaweed Pterocladiella capillacea (Gelidiaceae, Gelidiales).

    PubMed

    Errea, María I; Matulewicz, María C

    2003-04-22

    Sequential extraction of tetrasporic Pterocladiella capillacea with water at room temperature and then at 50 degrees C led to the isolation of two products that were each fractionated with cetrimide to give a soluble fraction and a precipitate. The precipitates were then subjected to fractional solubilization in solutions of increasing sodium chloride concentration. The whole treatment yielded two major fractions in each case, one soluble in the cetrimide medium and the other soluble in 0.5 M NaCl, which were further fractionated by anion-exchange chromatography. Structural analysis, carried out by methylation, desulfation-methylation, 13C NMR spectroscopy and determination of the absolute configuration of the 2,6-di-O-methylgalactose units in the permethylated products, indicated the presence of xylogalactans, with low content of 3,6-anhydrogalactose and low molecular weight. These polysaccharides varied in the level of xylopyranosyl and sulfate substitution, primarily on the 6-position of the 3-linked beta-D-galactopyranosyl and on the 3-position of the 4-linked alpha-galactopyranosyl units. Moreover, herein we report, for the first time, the presence of 3-substituted, 4-linked D-galactopyranosyl residues in an alga belonging to the Gelidiales.

  5. Structural characterisation and rheological properties of a polysaccharide from sesame leaves (Sesamum radiatum Schumach. & Thonn.).

    PubMed

    Nep, E I; Carnachan, S M; Ngwuluka, N C; Kontogiorgos, V; Morris, G A; Sims, I M; Smith, A M

    2016-11-05

    A polysaccharide from the leaves of Sesamum radiatum was extracted by maceration in deionized water followed by ethanol precipitation then chemically and physically characterised. Monosaccharide composition and linkages were determined by high performance anion exchange chromatography (HPAEC), gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) spectroscopy respectively. Sesamum gum was composed of glucuronic acid, mannose, galactose, and xylose with trace quantities of glucose, rhamnose and arabinose. Proton and (13)C NMR spectroscopy, and linkage analysis revealed a glucuronomannan based structure comprising a backbone of →4)-β-d-GlcpA-(1→2)-α-d-Manp-(1→ with side-chains of galactose and xylose. Hydrated sesamum gum displayed temperature independent viscoelastic properties with no thermal hysteresis. Intrinsic viscosity was determined to be 3.31 and 4.40dLg(-1) in 0.1M NaCl and deionised water respectively, while the critical concentration was determined to be 0.1% w/v. The characterisation performed in this study will help direct potential applications of this material in foods and pharmaceuticals.

  6. Structure of the N-acetyl-L-rhamnosamine-containing O-polysaccharide of Proteus vulgaris TG 155 from a new Proteus serogroup, O55.

    PubMed

    Kondakova, Anna N; Kolodziejska, Katarzyna; Zych, Krystyna; Senchenkova, Sof'ya N; Shashkov, Alexander S; Knirel, Yuriy A; Sidorczyk, Zygmunt

    2003-09-10

    The O-polysaccharide of the lipopolysaccharide (LPS) of Proteus vulgaris TG 155 was found to contain 2-acetamido-2,6-dideoxy-L-mannose (N-acetyl-L-rhamnosamine, L-RhaNAc), a monosaccharide that occurs rarely in Nature. The following structure of the O-polysaccharide was established by NMR spectroscopy, including 2D COSY, TOCSY, ROESY and 1H,13C HSQC experiments, along with chemical methods: [carbohydrate structure in text] Rabbit polyclonal O-antiserum against P. vulgaris TG 155 reacted with both core and O-polysaccharide moieties of the homologous LPS but showed no cross-reactivity with other LPS from the complete set of serologically different Proteus strains. Based on the unique O-polysaccharide structure and the serological data, we propose classifying P. vulgaris TG 155 into a new, separate Proteus O-serogroup, O55.

  7. A novel polysaccharide isolated from mulberry fruits (Murus alba L.) and its selenide derivative: structural characterization and biological activities.

    PubMed

    Chen, Chun; Zhang, Bin; Fu, Xiong; Liu, Rui Hai

    2016-06-15

    A novel polysaccharide (MFP3P) was isolated from Murus alba L. through the hot water extraction method followed by chromatographic purification. The chemical structure of MFP3P was elucidated by acid hydrolysis, Smith degradation and methylation analysis, along with FT-IR, GC-MS, (1)H and (13)C NMR spectroscopy. Its morphological properties were further characterized by SEM and AFM. The selenide of the polysaccharide (MFP3P-Se) was obtained by the Na2SeO3/BaCl2 method. The antioxidant properties showed that MFP3P-Se exhibited higher peroxy radical-scavenging capacity than MFP3P in vitro. Moreover, MFP3P-Se had more significant hypoglycemic effects than MFP3P through promoting pancreatic cell proliferation and increasing glucose metabolism and insulin secretion.

  8. Structure of a glycerol teichoic acid-like O-specific polysaccharide of Proteus vulgaris O12.

    PubMed

    Perepelov, A V; Torzewska, A; Shashkov, A S; Senchenkova, S N; Rozalski, A; Knirel, Y A

    2000-02-01

    A phosphorylated O-specific polysaccharide (O-antigen) was obtained by mild acid degradation of Proteus vulgaris O12 lipopolysaccharide and studied by sugar and methylation analyses, 1H-, 13C- and 31P-NMR spectroscopy, including two-dimensional COSY, TOCSY, NOESY, H-detected 1H, 13C and 1H, 31P heteronuclear multiple-quantum coherence experiments. It was found that the polysaccharide consists of pentasaccharide repeating units connected via a glycerol phosphate group, and has the following structure: where FucNAc is 2-acetamido-2,6-dideoxygalactose and the degree of O-acetylation at position 4 of GalNAc is approximately 25%. Immunochemical studies with P. vulgaris O12 O-antiserum suggested that the lipopolysaccharide studied shares common epitopes with the lipopolysaccharide core of P. vulgaris O8 and with the O-antigens of P. penneri strains 8 and 63.

  9. Self-Aggregation of Cryptococcus neoformans Capsular Glucuronoxylomannan Is Dependent on Divalent Cations▿ ‡

    PubMed Central

    Nimrichter, Leonardo; Frases, Susana; Cinelli, Leonardo P.; Viana, Nathan B.; Nakouzi, Antonio; Travassos, Luiz R.; Casadevall, Arturo; Rodrigues, Marcio L.

    2007-01-01

    The capsular components of the human pathogen Cryptococcus neoformans are transported to the extracellular space and then used for capsule enlargement by distal growth. It is not clear, however, how the glucuronoxylomannan (GXM) fibers are incorporated into the capsule. In the present study, we show that concentration of C. neoformans culture supernatants by ultrafiltration results in the formation of highly viscous films containing pure polysaccharide, providing a novel, nondenaturing, and extremely rapid method to isolate extracellular GXM. The weight-averaged molecular mass of GXM in the film, determined using multiangle laser light scattering, was ninefold smaller than that of GXM purified from culture supernatants by differential precipitation with cetyl trimethyl ammonium bromide (CTAB). Polysaccharides obtained either by ultrafiltration or by CTAB-mediated precipitation showed different reactivities with GXM-specific monoclonal antibodies. Viscosity analysis associated with inductively coupled plasma mass spectrometry and measurements of zeta potential in the presence of different ions implied that polysaccharide aggregation was a consequence of the interaction between the carboxyl groups of glucuronic acid and divalent cations. Consistent with this observation, capsule enlargement in living C. neoformans cells was influenced by Ca2+ in the culture medium. These results suggest that capsular assembly in C. neoformans results from divalent cation-mediated self-aggregation of extracellularly accumulated GXM molecules. PMID:17573547

  10. Isolation, structure, and surfactant properties of polysaccharides from Ulva lactuca L. from South China Sea.

    PubMed

    Tian, Hua; Yin, Xueqiong; Zeng, Qinghuan; Zhu, Li; Chen, Junhua

    2015-08-01

    Two polysaccharides (ULP1 and ULP2) were isolated through ultrasonic-assisted extraction from green seaweed Ulva lactuca L. which was collected from the South China Sea. The highest yield of 17.57% was obtained under the conditions of 2% NaOH, 90 °C, material/water mass ratio 1:80, liquid extraction 5h and subsequent ultrasound-assisted extraction 1h. The structure of ULPs were characterized with periodate oxidation followed by Smith degradation, (1)H NMR, (13)C NMR spectroscopy, FTIR, and GPC. The molecular weights of ULP1 and ULP2 were 189 kDa and 230 kDa, respectively. The structural characteristics of ULP1 and ULP2 were quite similar. They were composed of rhamnose, xylose, glucose, and glucuronic acid. The content of rhamnose, xylose, glucose, glucuronic acid, sulfate was 51.2%, 12.3%, 20.1%, 16.4%, 12.0% for ULP1, respectively, and 60.8%, 14.2%, 8.2%, 16.8%, 26.8%, respectively, for ULP2. Both ULP1 and ULP2 showed good surface activity. 5 mg/mL ULP1 (2.62×10(-2) mmol/L) decreased the water surface tension to 51.63 mN/m. The critical micellar concentration of ULP1 and ULP2 was 1.01 mg/mL (5.3×10(-3) mmol/L) and 1.14 mg/mL (5.0×10(-3) mmol/L), respectively.

  11. Biofilms from Klebsiella pneumoniae: Matrix Polysaccharide Structure and Interactions with Antimicrobial Peptides

    PubMed Central

    Benincasa, Monica; Lagatolla, Cristina; Dolzani, Lucilla; Milan, Annalisa; Pacor, Sabrina; Liut, Gianfranco; Tossi, Alessandro; Cescutti, Paola; Rizzo, Roberto

    2016-01-01

    Biofilm matrices of two Klebsiella pneumoniae clinical isolates, KpTs101 and KpTs113, were investigated for their polysaccharide composition and protective effects against antimicrobial peptides. Both strains were good biofilm producers, with KpTs113 forming flocs with very low adhesive properties to supports. Matrix exopolysaccharides were isolated and their monosaccharide composition and glycosidic linkage types were defined. KpTs101 polysaccharide is neutral and composed only of galactose, in both pyranose and furanose ring configurations. Conversely, KpTs113 polysaccharide is anionic due to glucuronic acid units, and also contains glucose and mannose residues. The susceptibility of the two strains to two bovine cathelicidin antimicrobial peptides, BMAP-27 and Bac7(1–35), was assessed using both planktonic cultures and biofilms. Biofilm matrices exerted a relevant protection against both antimicrobials, which act with quite different mechanisms. Similar protection was also detected when antimicrobial peptides were tested against planktonic bacteria in the presence of the polysaccharides extracted from KpTs101 and KpTs113 biofilms, suggesting sequestering adduct formation with antimicrobials. Circular dichroism experiments on BMAP-27 in the presence of increasing amounts of either polysaccharide confirmed their ability to interact with the peptide and induce an α-helical conformation. PMID:27681920

  12. Structure and anticoagulant property of a sulfated polysaccharide isolated from the green seaweed Monostroma angicava.

    PubMed

    Li, Na; Liu, Xue; He, Xiaoxi; Wang, Shuyao; Cao, Sujian; Xia, Zheng; Xian, Huali; Qin, Ling; Mao, Wenjun

    2017-03-01

    An anticoagulant-active polysaccharide PF2 was extracted with boiling water from the green seaweed Monostroma angicava, further purified by anion-exchange and size-exclusion chromatography. PF2 was a rhamnan-type sulfated polysaccharide with molecular weight of about 88.1kDa. Results of chemical and spectroscopic analyses demonstrated that PF2 consisted of→3)-α-l-Rhap-(1→ and →2)-α-l-Rhap-(1→residues, with partially branches at C-2 of→3)-α-l-Rhap-(1→residues. Sulfate groups were substituted at C-3 of →2)-α-l-Rhap-(1→ residues. The sulfated polysaccharide PF2 had a high anticoagulant action, and the mechanism of anticoagulant activity mediated by PF2 was mainly attributed to strong potentiation thrombin by heparin cofactor II. PF2 also exhibited weak effect on antithrombin-dependent thrombin or factor Xa inhibition. The fibrin(ogen)olytic activity and thrombolytic activity of PF2 were also evaluated. The investigation revealed that PF2 was a novel sulfated rhamnan differing from previously described sulfated polysaccharides from green seaweed and could be a potential anticoagulant polysaccharide.

  13. Biofilms from Klebsiella pneumoniae: Matrix Polysaccharide Structure and Interactions with Antimicrobial Peptides.

    PubMed

    Benincasa, Monica; Lagatolla, Cristina; Dolzani, Lucilla; Milan, Annalisa; Pacor, Sabrina; Liut, Gianfranco; Tossi, Alessandro; Cescutti, Paola; Rizzo, Roberto

    2016-08-10

    Biofilm matrices of two Klebsiella pneumoniae clinical isolates, KpTs101 and KpTs113, were investigated for their polysaccharide composition and protective effects against antimicrobial peptides. Both strains were good biofilm producers, with KpTs113 forming flocs with very low adhesive properties to supports. Matrix exopolysaccharides were isolated and their monosaccharide composition and glycosidic linkage types were defined. KpTs101 polysaccharide is neutral and composed only of galactose, in both pyranose and furanose ring configurations. Conversely, KpTs113 polysaccharide is anionic due to glucuronic acid units, and also contains glucose and mannose residues. The susceptibility of the two strains to two bovine cathelicidin antimicrobial peptides, BMAP-27 and Bac7(1-35), was assessed using both planktonic cultures and biofilms. Biofilm matrices exerted a relevant protection against both antimicrobials, which act with quite different mechanisms. Similar protection was also detected when antimicrobial peptides were tested against planktonic bacteria in the presence of the polysaccharides extracted from KpTs101 and KpTs113 biofilms, suggesting sequestering adduct formation with antimicrobials. Circular dichroism experiments on BMAP-27 in the presence of increasing amounts of either polysaccharide confirmed their ability to interact with the peptide and induce an α-helical conformation.

  14. Polysaccharides from the green seaweed Codium decorticatum. Structure and cell wall distribution.

    PubMed

    Fernández, Paula Virginia; Raffo, María Paula; Alberghina, Josefina; Ciancia, Marina

    2015-03-06

    The cell wall polysaccharides from Codium decorticatum and their assembly were studied and these results were compared with those obtained previously for this genus. The water soluble polysaccharides are: (i) Pyruvylated and sulfated 3- and 6-linked β-D-galactans with sulfate mainly on C-4 and also on C-6. Pyruvate ketals are linked to O-3 and O-4 of terminal β-D-galactose or O-4 and O-6 of 3-linked β-D-galactose. (ii) Sulfated 3-linked β-L-arabinans substituted on C-2 or C-2 and C-4 predominantly with sulfate, but also with single stubs of arabinose, and (iii) 4-linked β-D-mannans with a low degree of sulfation on C-2. The whole polysaccharide system comprises 6.9% of sulfated polysaccharides and 32.9% of fibrillar polysaccharides, mostly insoluble mannans. By in situ localization it was possible to detect two similar fibrillar layers separated by a zone rich in charged polymers. Besides, arabinogalactan proteins co-localized with the fibrillar components.

  15. Uronic polysaccharide degrading enzymes.

    PubMed

    Garron, Marie-Line; Cygler, Miroslaw

    2014-10-01

    In the past several years progress has been made in the field of structure and function of polysaccharide lyases (PLs). The number of classified polysaccharide lyase families has increased to 23 and more detailed analysis has allowed the identification of more closely related subfamilies, leading to stronger correlation between each subfamily and a unique substrate. The number of as yet unclassified polysaccharide lyases has also increased and we expect that sequencing projects will allow many of these unclassified sequences to emerge as new families. The progress in structural analysis of PLs has led to having at least one representative structure for each of the families and for two unclassified enzymes. The newly determined structures have folds observed previously in other PL families and their catalytic mechanisms follow either metal-assisted or Tyr/His mechanisms characteristic for other PL enzymes. Comparison of PLs with glycoside hydrolases (GHs) shows several folds common to both classes but only for the β-helix fold is there strong indication of divergent evolution from a common ancestor. Analysis of bacterial genomes identified gene clusters containing multiple polysaccharide cleaving enzymes, the Polysaccharides Utilization Loci (PULs), and their gene complement suggests that they are organized to process completely a specific polysaccharide.

  16. Structure of the oligosaccharides isolated from Prosopis juliflora (Sw.) DC. seed polysaccharide.

    PubMed

    Bhatia, Himani; Gupta, P K; Soni, P L

    2014-01-30

    A water soluble polysaccharide isolated from Prosopis juliflora seed was purified and major homogenous fraction obtained by GPC. Complete hydrolysis of the polysaccharide followed by paper chromatography and GLC analysis indicated the presence of d-galactose and d-mannose in the ratio 1:1.10, respectively. Partial hydrolysis of the polysaccharide furnished one hepta-(I), one octa-(II) and nona-(III) saccharides. Hydrolysis of oligosaccharide I, II and III followed by GLC analysis furnished d-galactose and d-mannose in the ratio 3:4, 3:5 and 5:4, respectively. Methylation analysis, periodate oxidation and (1)H NMR spectral studies of oligosaccharides indicated the presence of (1→4) mannose units linked to (1→6) galactose units.

  17. Structural elucidation of a cell wall fungal polysaccharide isolated from Ustilaginoidea virens, a pathogenic fungus of Oriza sativa and Zea mays.

    PubMed

    Leal, J A; Jiménez-Barbero, Jesús; Bernabé, Manuel; Prieto, Alicia

    2008-11-24

    The alkali-extractable water-soluble polysaccharides (F1SS) isolated from the outer cell wall of two strains of Ustilaginoidea virens have been studied by chemical and methylation analyses, and 1D and 2D (1)H and (13)C NMR spectroscopy. The structures of these polysaccharides are very similar, and can be described by the following idealized repeating unit: where n and m are approximately 1 and 2, respectively.

  18. Structural, physicochemical, antioxidant and antitumor property of an acidic polysaccharide from Polygonum multiflorum.

    PubMed

    Zhu, Weili; Xue, Xiaoping; Zhang, Zhanjun

    2017-03-01

    In this study, the structural characterization, physicochemical property, antioxidant and antitumor activity of an acidic polysaccharide (APS) from Polygonum multiflorum were investigated. Monosaccharide composition analysis showed APS was composed of arabinose, rhamnose, galactose and galacturonic acid in the molar ratio of 1.23:1.32:1.48:1.00. The presence of uronic acid was also confirmed by the bands at 1740, 1645 and 1425cm(-1) on Fourier transform-infrared spectroscopy. Methylation and nuclear magnetic resonance analyses showed APS was mainly composed by the residues of →5)-α-l-Araf-(1→, →3)-β-d-Galp-(1→, →3,6)-β-d-Galp-(1→, →4)-α-d-GalAp-(1→ and →2)-α-l-Rhap-(1→ in the backbone. The non-reducing terminal α-l-Araf-(1→ was probably attached to the O-6 position of →3,6)-β-d-Galp-(1→ residues. Besides, APS exhibited rod-like and flaky shapes with rough surface. The initial decomposition of APS occurred at 172°C, and the rapidest weight loss rate of APS appeared at 320°C. Antioxidant activity assay showed the DPPH radical scavenging activity of APS was 67.5% at 1mg/mL. At the concentration of 400μg/mL, the antiproliferation activities of APS against HepG-2 and BGC-823 cells were 65.28% and 51.57%, respectively. Our results suggested APS could be a potential antioxidant and antitumor agent.

  19. Structure Elucidation of a Polysaccharide from Umbilicaria esculenta and Its Immunostimulatory Activity

    PubMed Central

    Zhang, Bi-Wei; Xu, Jin-Long; Zhang, Hua; Zhang, Qiang; Lu, Jie; Wang, Jun-Hui

    2016-01-01

    Umbilicaria esculenta has been used as a tonic food in China for several centuries owing to its pleasant flavor and health benefits. In this study, a water soluble polysaccharide, which we designated as UP2, with an average molecular weight of 3.33 × 105 Da, was isolated from U. esculenta cultivated in the Huangshan Mountain, by consecutive hot water extraction and anion-exchange chromatography. Gas chromatography analysis indicated that UP2 contained three kinds of monosaccharides, including mannose, glucose, and galactose at a molar ratio of 1.7:1.0:1.2. Linkage analysis of UP2 revealed the presence of (1 → 6)-linked glucosyl, (1 → 3,6)-linked glucosyl, t-linked galactosyl, (1 → 6)-linked galactosyl and (1 → 6)-linked mannosyl at a molar ratio of 0.7:4.6:4.1:2.2:9.1. Structural analysis determined that UP2 possessed a backbone consisting of (1 → 6)-linked β-D-glucopyranosyl and (1 → 6)-linked α-D-mannopyranosyl residues, which substituted at the O-3 position of (1 → 6)-linked β-D-glucopyranosyl residues by branches of (1 → 6)-linked α-D-galactopyranosyl and 1-linked β-D-galactopyranosyl residues. Immunostimulatory activity analysis showed that UP2 could stimulate the proliferation of RAW264.7 cells in a dose-dependent manner, and all the samples (20–500 μg/mL) were found to enhance nitric oxide production. The highest phagocytic activity of UP2 was observed at 200 μg/mL. Thus, UP2 may be a potential source of biological and pharmacological agents. PMID:27997616

  20. Rheological Flow Behavior of Structural Polysaccharides from Edible Tender Cladodes of Wild, Semidomesticated and Cultivated 'Nopal' (Opuntia) of Mexican Highlands.

    PubMed

    López-Palacios, C; Peña-Valdivia, C B; Rodríguez-Hernández, A I; Reyes-Agüero, J A

    2016-12-01

    The aim of this study was to quantify the content of polysaccharides of edible tender cladodes (nopalitos) of three species of Opuntia and to evaluate the rheological flow behavior of isolated polysaccharides. A completely randomized experimental design was used to characterize a wild (O. streptacantha), a semidomesticated (O. megacantha) and a domesticated (O. ficus-indica) species. Mucilage content was higher (4.93 to 12.43 g 100 g(-1) dry matter), tightly bound hemicelluloses were lower (3.32 to 1.81 g 100 g(-1) dry matter) and pectins and loosely bound hemicelluloses were not different in wild than in domesticated species. Aqueous solution/suspensions of mucilage, pectins, hemicellulose and cellulose of all species showed non-Newtonian behavior under simple shear flow. The flow behavior of the structural polysaccharides was well described by the Ostwald de-Waele model. Pectins and mucilages exhibited the highest consistency indexes (K values ranged from 0.075 to 0.177 Pas(n)) with a moderated shear-thinning behavior (n values ranged from 0.53 to 0.67). Cellulose dispersions exhibited the most shear-thinning behavior (n values ranged from 0.17 to 0.41) and hemicelluloses showed a tendency to Newtonian flow (n values ranged from 0.82 to 0.97). The rheological flow properties of these polysaccharides may be useful to improve the textural and sensory qualities of some foods and pharmaceutical materials. Moreover, they can emerge as functional ingredients mainly due to the nutraceutical properties that have been attributed to nopalitos.

  1. Effects of light intensity on components and topographical structures of extracellular polysaccharides from the cyanobacteria Nostoc sp.

    PubMed

    Ge, Hongmei; Xia, Ling; Zhou, Xuping; Zhang, Delu; Hu, Chunxiang

    2014-02-01

    A study on the effects of light intensity (40 and 80 μE/m(2)/sec) on the components and topographical structures of extracellular polysaccharides (EPS) was carried out in cyanobacteria Nostoc sp.. EPS yield increased with light intensity. However, light intensity did not significantly affect the EPS fractions and monosaccharide composition. Higher light intensity generally resulted in higher protein content of EPS in similar fractions. The topographical structure of EPS, investigated by atomic force microscopy, appeared as spherical lumps, chains and networks. The long chains were observed at higher light intensity. Thus, light intensity affected the yield and nature of EPS.

  2. Structure and serological specificity of a new acidic O-specific polysaccharide of Proteus vulgaris O45.

    PubMed

    Bartodziejska, B; Shashkov, A S; Torzewska, A; Grachev, A A; Ziolkowski, A; Paramonov, N A; Rozalski, A; Knirel, Y A

    1999-01-01

    The following structure of the O-specific polysaccharide (OPS) of Proteus vulgaris O45 lipopolysaccharide (LPS) was established using 1H- and 13C-NMR spectroscopy, including two-dimensional NOESY and H-detected 1H, 13C heteronuclear multiple-quantum coherence ( HMQC) experiments: [structure: see text text] Immunochemical studies, using rabbit polyclonal anti-P. vulgaris O45 serum and LPS, OPS and Smith-degraded OPS of P. vulgaris O45, showed the importance of beta-D-GlcA in manifesting the serological specificity of the O-antigen studied.

  3. Multidimensional solid-state NMR studies of the structure and dynamics of pectic polysaccharides in uniformly 13C-labeled Arabidopsis primary cell walls

    SciTech Connect

    Dick-Perez, Marilu; Wang, Tuo; Salazar, Andre; Zabotina, Olga A.; Hong, Mei

    2012-07-08

    Plant cell wall (CW) polysaccharides are responsible for the mechanical strength and growth of plant cells; however, the high-resolution structure and dynamics of the CW polysaccharides are still poorly understood because of the insoluble nature of these molecules. Here, we use 2D and 3D magic-angle-spinning (MAS) solid-state NMR (SSNMR) to investigate the structural role of pectins in the plant CW. Intact and partially depectinated primary CWs of Arabidopsis thaliana were uniformly labeled with 13C and their NMR spectra were compared. Recent 13C resonance assignment of the major polysaccharides in Arabidopsis thaliana CWs allowed us to determine the effects of depectination on the intermolecular packing and dynamics of the remaining wall polysaccharides. 2D and 3D correlation spectra show the suppression of pectin signals, confirming partial pectin removal by chelating agents and sodium carbonate. Importantly, higher cross peaks are observed in 2D and 3D 13C spectra of the depectinated CW, suggesting higher rigidity and denser packing of the remaining wall polysaccharides compared with the intact CW. 13C spin–lattice relaxation times and 1H rotating-frame spin–lattice relaxation times indicate that the polysaccharides are more rigid on both the nanosecond and microsecond timescales in the depectinated CW. Taken together, these results indicate that pectic polysaccharides are highly dynamic and endow the polysaccharide network of the primary CW with mobility and flexibility, which may be important for pectin functions. This study demonstrates the capability of multidimensional SSNMR to determine the intermolecular interactions and dynamic structures of complex plant materials under near-native conditions. Copyright © 2012 John Wiley & Sons, Ltd.

  4. Structure of the O-specific polysaccharide from the lipopolysaccharide of Psychrobacter cryohalolentis K5(T) containing a 2,3,4-triacetamido-2,3,4-trideoxy-L-arabinose moiety.

    PubMed

    Kondakova, Anna N; Novototskaya-Vlasova, Kseniya A; Arbatsky, Nikolay P; Drutskaya, Marina S; Shcherbakova, Victoria A; Shashkov, Alexander S; Gilichinsky, David A; Nedospasov, Sergei A; Knirel, Yuriy A

    2012-12-28

    A novel constituent of bacterial polysaccharides, 2,3,4-triacetamido-2,3,4-trideoxy-L-arabinose, was found in the O-specific polysaccharide from the lipopolysaccharide of Psychrobacter cryohalolentis K5(T) and identified by 1D and 2D (1)H and (13)C NMR studies of the polysaccharide and a disaccharide obtained by solvolysis of the polysaccharide with triflic acid. The following structure of the branched polysaccharide was established by sugar analysis, triflic acid solvolysis, Smith degradation, and 2D NMR spectroscopy.

  5. Development of an opsonin inhibition assay for evaluation of complex polysaccharide protective epitopes.

    PubMed

    McNeely, Tessie; Luo, Shengyuan; Manger, Walt; Herber, Wayne; Schofield, Tim; Tan, Charles; Newman, Kathy; Sadoff, Jerald; Donnelly, John; Cross, Alan

    2006-03-10

    The induction of opsonic antibodies directed against capsular polysaccharides (Ps) is an important mechanism by which immunization protects against the development of invasive pneumococcal (Pn) infection. In preparing Pn vaccines, it is necessary to compare different manufacturing lots of capsular Ps, or to compare oligosaccharides used for conjugate vaccines with native capsular Ps, in order to insure that important epitopes of the Ps are maintained. We have developed an opsonic-antibody inhibition assay (OIA) to compare the functional epitopes of different capsular Ps preparations in vitro. Components of the OIA are primary neutrophils, rabbit complement (C'), and type-specific antibody (Ab). After conditions for optimal opsonic killing were determined for each Pn serotype, anti-Pn Ab was pre-incubated with different dilutions of purified capsular Ps, then added to the OIA mix. Plotting the % bacteria killed versus Ps concentration (log transformed) yielded a linear curve that was used to quantify the concentration of capsular Ps which inhibited the bacteria killing by 50% (IC50). The IC50 was determined for 8 Pn Ps types. These ranged between 6 ng/ml for type 6B and 1268 ng/ml for type 23F. Importantly OIA curves were statistically identical for two different manufacturing lots of capsular Ps for the 8 Pn Ps types. We conclude that differences among capsular Ps used for Pn vaccines could be detected with an OIA assay and these differences may predict the ability of Ps preparations to induce functionally active antibody when formulated into vaccines.

  6. Purification and Partial Structural Characterization of a Complement Fixating Polysaccharide from Rhizomes of Ligusticum chuanxiong.

    PubMed

    Zou, Yuan-Feng; Fu, Yu-Ping; Chen, Xing-Fu; Austarheim, Ingvild; Inngjerdingen, Kari Tvete; Huang, Chao; Eticha, Lemlem Dugassa; Song, Xu; Li, Lixia; Feng, Bin; He, Chang-Liang; Yin, Zhong-Qiong; Paulsen, Berit Smestad

    2017-02-14

    Rhizome of Ligusticum chuanxiong is an effective medical plant, which has been extensively applied for centuries in migraine and cardiovascular diseases treatment in China. Polysaccharides from this plant have been shown to have interesting bioactivities, but previous studies have only been performed on the neutral polysaccharides. In this study, LCP-I-I, a pectic polysaccharide fraction, was obtained from the 100 °C water extracts of L. chuangxiong rhizomes and purified by diethylaminethyl (DEAE) sepharose anion exchange chromatography and gel filtration. Monosaccharide analysis and linkage determination in addition to Fourier transform infrared (FT-IR) spectrometer and Nuclear magnetic resonance (NMR) spectrum, indicated that LCP-I-I is a typical pectic polysaccharide, with homo-galacturonan and rhamnogalacturonan type I regions and arabinogalactan type I and type II (AG-I/AG-II) side chains. LCP-I-I exhibited potent complement fixation activity, ICH50 of 26.3 ± 2.2 µg/mL, and thus has potential as a natural immunomodulator.

  7. Hip Capsular Reconstruction Using Dermal Allograft.

    PubMed

    Chahla, Jorge; Dean, Chase S; Soares, Eduardo; Mook, William R; Philippon, Marc J

    2016-04-01

    Because hip arthroscopic procedures are increasing in number, complications related to the operation itself are starting to emerge. Whereas the capsule has been recognized as an important static stabilizer for the hip, it has not been until recently that surgeons have realized the importance of its preservation and restoration. Disruption of the capsule during arthroscopic procedures is a potential contributor to postoperative iatrogenic hip instability. In cases of a symptomatic deficient capsule, a capsular reconstruction is mandatory because instability may lead to detrimental chondral and labral changes. The purpose of this report was to describe our technique for arthroscopic hip capsular reconstruction using dermal allograft.

  8. Following fungal melanin biosynthesis with solid-state NMR: biopolymer molecular structures and possible connections to cell-wall polysaccharides.

    PubMed

    Zhong, Junyan; Frases, Susana; Wang, Hsin; Casadevall, Arturo; Stark, Ruth E

    2008-04-22

    Melanins serve a variety of protective functions in plants and animals, but in fungi such as Cryptococcus neoformans they are also associated with virulence. A recently developed solid-state nuclear magnetic resonance (NMR) strategy, based on the incorporation of site-specific (13)C-enriched precursors into melanin, followed by spectroscopy of both powdered and solvent-swelled melanin ghosts, was used to provide new molecular-level insights into fungal melanin biosynthesis. The side chain of an l-dopa precursor was shown to cyclize and form a proposed indole structure in C. neoformans melanin, and modification of the aromatic rings revealed possible patterns of polymer chain elongation and cross-linking within the biopolymer. Mannose supplied in the growth medium was retained as a beta-pyranose moiety in the melanin ghosts even after exhaustive degradative and dialysis treatments, suggesting the possibility of tight binding or covalent incorporation of the pigment into the polysaccharide fungal cell walls. In contrast, glucose was scrambled metabolically and incorporated into both polysaccharide cell walls and aliphatic chains present in the melanin ghosts, consistent with metabolic use as a cellular nutrient as well as covalent attachment to the pigment. The prominent aliphatic groups reported previously in several fungal melanins were identified as triglyceride structures that may have one or more sites of chain unsaturation. These results establish that fungal melanin contains chemical components derived from sources other than l-dopa polymerization and suggest that covalent linkages between l-dopa-derived products and polysaccharide components may serve to attach this pigment to cell wall structures.

  9. Structural characterization and anti-aging activity of a novel extracellular polysaccharide from fungus Phellinus sp. in a mammalian system.

    PubMed

    Ma, Xiao-Kui; Guo, Dan Dan; Peterson, Eric Charles; Dun, Ying; Li, Dan Yang

    2016-08-10

    Little is known about the chemical structure of purified extracellular polysaccharides from Phellinus sp., a fungal species with known medicinal properties. A combination of IR spectroscopy, methylation analysis and NMR were performed for the structural analysis of a purified extracellular polysaccharide derived from Phellinus sp. culture, denoted as SHP-1, along with an evaluation of the anti-aging effect in vivo of the polysaccharide supplementation. The structure of SHP-1 was established, with a backbone composed of →2,4)-α-d-glucopyranose-(1→ and →2)-β-d-mannopyranose-(1→ and two terminal glucopyranose branches. Biochemical analysis from mammalian animal experiments demonstrated that SHP-1 possesses the ability to enhance antioxidant enzyme activities, such as catalase (CAT) and superoxide dismutase (SOD) activities, Trolox equivalent antioxidant capacity (TEAC) in serum of d-galactose-aged mice, while reducing lipofuscin levels, another indicator of cell aging, indicating a potential association with anti-aging activities in a dose dependent manner. This compound had a favourable influence on immune organ indices, and a marked amelioration ability of histopathological hepatic lesions such as necrosis, karyolysis and reduced inflammation and apoptosis in mouse hepatocytes. These results suggest that SHP-1 has strong antioxidant activities and a significant protective effect against oxidative stress or hepatotoxicity induced by d-galactose in mice and it could be developed as a food ingredient or a pharmaceutical to prevent many age-associated diseases such as major depressive disorder and hepatotoxicity. To our knowledge, this is the first report on the antioxidant effects of a novel purified exopolysaccharide derived from Phellinus sp.

  10. Polysaccharides of the red algae.

    PubMed

    Usov, Anatolii I

    2011-01-01

    Red algae (Rhodophyta) are known as the source of unique sulfated galactans, such as agar, agarose, and carrageenans. The wide practical uses of these polysaccharides are based on their ability to form strong gels in aqueous solutions. Gelling polysaccharides usually have molecules built up of repeating disaccharide units with a regular distribution of sulfate groups, but most of the red algal species contain more complex galactans devoid of gelling ability because of various deviations from the regular structure. Moreover, several red algae may contain sulfated mannans or neutral xylans instead of sulfated galactans as the main structural polysaccharides. This chapter is devoted to a description of the structural diversity of polysaccharides found in the red algae, with special emphasis on the methods of structural analysis of sulfated galactans. In addition to the structural information, some data on the possible use of red algal polysaccharides as biologically active polymers or as taxonomic markers are briefly discussed.

  11. New Ulvan-Degrading Polysaccharide Lyase Family: Structure and Catalytic Mechanism Suggests Convergent Evolution of Active Site Architecture.

    PubMed

    Ulaganathan, ThirumalaiSelvi; Boniecki, Michal T; Foran, Elizabeth; Buravenkov, Vitaliy; Mizrachi, Naama; Banin, Ehud; Helbert, William; Cygler, Miroslaw

    2017-03-23

    Ulvan is a complex sulfated polysaccharide biosynthesized by green seaweed and contains predominantly rhamnose, xylose, and uronic acid sugars. Ulvan-degrading enzymes have only recently been identified and added to the CAZy ( www.cazy.org ) database as family PL24, but neither their structure nor catalytic mechanism(s) are yet known. Several homologous, new ulvan lyases, have been discovered in Pseudoalteromonas sp. strain PLSV, Alteromonas LOR, and Nonlabens ulvanivorans, defining a new family PL25, with the lyase encoded by the gene PLSV_3936 being one of them. This enzyme cleaves the glycosidic bond between 3-sulfated rhamnose (R3S) and glucuronic acid (GlcA) or iduronic acid (IdoA) via a β-elimination mechanism. We report the crystal structure of PLSV_3936 and its complex with a tetrasaccharide substrate. PLSV_3936 folds into a seven-bladed β-propeller, with each blade consisting of four antiparallel β-strands. Sequence conservation analysis identified a highly conserved region lining at one end of a deep crevice on the protein surface. The putative active site was identified by mutagenesis and activity measurements. Crystal structure of the enzyme with a bound tetrasaccharide substrate confirmed the identity of base and acid residues and allowed determination of the catalytic mechanism and also the identification of residues neutralizing the uronic acid carboxylic group. The PLSV_3936 structure provides an example of a convergent evolution among polysaccharide lyases toward a common active site architecture embedded in distinct folds.

  12. Structure of the O-polysaccharide of Proteus serogroup O34 containing 2-acetamido-2-deoxy-alpha-D-galactosyl phosphate.

    PubMed

    Perepelov, Andrei V; Kołodziejska, Katarzyna; Kondakova, Anna N; Wykrota, Marianna; Knirel, Yuriy A; Sidorczyk, Zygmunt; Rozalski, Antoni

    2004-08-23

    On mild acid degradation of the lipopolysaccharide of Proteus vulgaris O34, strain CCUG 4669, the O-polysaccharide was cleaved at a glycosyl-phosphate linkage that is present in the main chain. The resultant phosphorylated oligosaccharides and an alkali-treated lipopolysaccharide were studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, and the following structure of the branched tetrasaccharide phosphate repeating unit of the O-polysaccharide was established: [carbohydrate structure: see text]The O-polysaccharide of Proteus mirabilis strain TG 276 was found to have the same structure and, based on the structural and serological data, this strain was proposed to be classified into the same Proteus serogroup O34.

  13. Kingella kingae Expresses Four Structurally Distinct Polysaccharide Capsules That Differ in Their Correlation with Invasive Disease

    PubMed Central

    Porsch, Eric A.; Seed, Patrick C.; Heiss, Christian; Naran, Radnaa; Amit, Uri; Yagupsky, Pablo; Azadi, Parastoo; St. Geme, Joseph W.

    2016-01-01

    Kingella kingae is an encapsulated gram-negative organism that is a common cause of osteoarticular infections in young children. In earlier work, we identified a glycosyltransferase gene called csaA that is necessary for synthesis of the [3)-β-GalpNAc-(1→5)-β-Kdop-(2→] polysaccharide capsule (type a) in K. kingae strain 269–492. In the current study, we analyzed a large collection of invasive and carrier isolates from Israel and found that csaA was present in only 47% of the isolates. Further examination of this collection using primers based on the sequence that flanks csaA revealed three additional gene clusters (designated the csb, csc, and csd loci), all encoding predicted glycosyltransferases. The csb locus contains the csbA, csbB, and csbC genes and is associated with a capsule that is a polymer of [6)-α-GlcpNAc-(1→5)-β-(8-OAc)Kdop-(2→] (type b). The csc locus contains the cscA, cscB, and cscC genes and is associated with a capsule that is a polymer of [3)-β-Ribf-(1→2)-β-Ribf-(1→2)-β-Ribf-(1→4)-β-Kdop-(2→] (type c). The csd locus contains the csdA, csdB, and csdC genes and is associated with a capsule that is a polymer of [P-(O→3)[β-Galp-(1→4)]-β-GlcpNAc-(1→3)-α-GlcpNAc-1-] (type d). Introduction of the csa, csb, csc, and csd loci into strain KK01Δcsa, a strain 269–492 derivative that lacks the native csaA gene, was sufficient to produce the type a capsule, type b capsule, type c capsule, and type d capsule, respectively, indicating that these loci are solely responsible for determining capsule type in K. kingae. Further analysis demonstrated that 96% of the invasive isolates express either the type a or type b capsule and that a disproportionate percentage of carrier isolates express the type c or type d capsule. These results establish that there are at least four structurally distinct K. kingae capsule types and suggest that capsule type plays an important role in promoting K. kingae invasive disease. PMID:27760194

  14. Biochemical And Genetic Modification Of Polysaccharides

    NASA Technical Reports Server (NTRS)

    Kern, Roger G.; Petersen, Gene R.; Richards, Gil F.

    1993-01-01

    Bacteriophages producing endopolysaccharase-type enzymes used to produce, isolate, and purify high yields of modified polysaccharides from polysaccharides produced by, and incorporated into capsules of, certain bacteria. Bacteriophages used in conversion of native polysaccharide materials into polymers of nearly uniform high molecular weight or, alternatively, into highly pure oligosaccharides. Also used in genetic selection of families of polysaccharides structurally related to native polysaccharide materials, but having altered properties. Resulting new polysaccharides and oligosaccharides prove useful in variety of products, including pharmaceutical chemicals, coating materials, biologically active carbohydrates, and drag-reducing additives for fluids.

  15. Role of capsular modified heptose in the virulence of Campylobacter jejuni.

    PubMed

    Wong, Anthony; Lange, Dirk; Houle, Sebastien; Arbatsky, Nikolay P; Valvano, Miguel A; Knirel, Yuriy A; Dozois, Charles M; Creuzenet, Carole

    2015-06-01

    The Campylobacter jejuni capsular polysaccharide is important for virulence and often contains a modified heptose. In strain ATCC 700819 (a.k.a. NCTC 11168), the modified heptose branches off from the capsular backbone and is directly exposed to the environment. We reported previously that the enzymes encoded by wcaG, mlghB and mlghC are involved in heptose modification. Here, we show that inactivation of any of these genes leads to production of capsule lacking modified heptose and alters the transcription of other capsule modification genes differentially. Inactivation of mlghB or mlghC, but not of wcaG, decreased susceptibility to bile salts and abrogated invasion of intestinal cells. All mutants showed increased sensitivity to serum killing, especially wcaG::cat, and had defects in colonization and persistence in chicken intestine, but did not show significant differences in adhesion, phagocytosis and intracellular survival in murine macrophages. Together, our findings suggest that the capsular heptose modification pathway contributes to bacterial resistance against gastrointestinal host defenses and supports bacterial persistence via its role in serum resistance and invasion of intestinal cells. Our data further suggest a dynamic regulation of expression of this pathway in the gastrointestinal tract.

  16. Structural features of pectic polysaccharides from the skin of Opuntia ficus-indica prickly pear fruits.

    PubMed

    Habibi, Y; Heyraud, A; Mahrouz, M; Vignon, M R

    2004-04-28

    After removal of the mucilage with water at room temperature, pectic polysaccharides were solubilized from Opuntia ficus-indica fruit skin, by sequential extraction with water at 60 degrees C (WSP) and EDTA solution at 60 degrees C (CSP). Polysaccharides with neutral sugar content of 0.48 and 0.36 mol/mol galacturonic acid residue were obtained, respectively, in the WSP and CSP extracts. These pectic polysaccharides were de-esterified and fractionated by anion-exchange chromatography, yielding for each extract five fractions, which were thereafter purified by size-exclusion chromatography. Two of these purified fractions were characterized by sugar analysis combined with methylation and reduction-methylation analysis. The study was then supported by (1)H and (13)C NMR spectroscopy. The results showed that the water-soluble fraction WSP3 and the EDTA soluble fraction CSP3, consisted of a disaccharide repeating unit -->2)-alpha-l-Rhap-(1-->4)-alpha-d-GalpA-(1--> backbone, with side chains attached to O-4 of the rhamnosyl residues. The side chains contained highly branched alpha-(1-->5)-linked arabinan and short linear beta-(1-->4)-linked galactan.

  17. Structural characterization and anticoagulant activity of a sulfated polysaccharide from the green alga Codium divaricatum.

    PubMed

    Li, Na; Mao, Wenjun; Yan, Mengxia; Liu, Xue; Xia, Zheng; Wang, Shuyao; Xiao, Bo; Chen, Chenglong; Zhang, Lifang; Cao, Sujian

    2015-05-05

    A sulfated polysaccharide, designated CP2-1, was isolated from the green alga Codium divaricatum by water extraction and purified by anion-exchange and size-exclusion chromatography. CP2-1 is a galactan which is highly sulfated and substituted with pyruvic acid ketals. On the basis of chemical and spectroscopic analyses, the backbone of CP2-1 was mainly composed of (1→3)-β-d-galactopyranose residues, branched by single (1→)-β-d-galactopyranose units attached to the main chain at C-4 positions. The degree of branching was estimated to be about 12.2%. Sulfate groups were at C-4 of (1→3)-β-d-galactopyranose and C-6 of non-reducing terminal galactose residues. In addition, the ketals of pyruvic acid were found at 3,4- of non-reducing terminal galactose residues forming a five-membered ring. CP2-1 possessed a high anticoagulant activity as assessed by the activated partial thromboplastin time and thrombin time assays. The investigation demonstrated that CP2-1 was an anticoagulant-active sulfated polysaccharide distinguishing from other sulfated polysaccharides from marine green algae.

  18. Antibiofilm polysaccharides

    PubMed Central

    Rendueles, Olaya; Kaplan, Jeffrey B.; Ghigo, Jean-Marc

    2012-01-01

    Summary Bacterial extracellular polysaccharides have been shown to mediate many of the cell-to cell and cell-to-surface interactions that are required for the formation, cohesion and stabilization of bacterial biofilms. However, recent studies have identified several bacterial polysaccharides that inhibit biofilm formation by a wide-spectrum of bacteria and fungi both in vitro and in vivo. This review discusses the composition, modes of action, and potential biological roles of antibiofilm polysaccharides recently identified in bacteria and eukaria. Some of these molecules may have technological applications as antibiofilm agents in industry and medicine. PMID:22730907

  19. Simvastatin Reduces Capsular Fibrosis around Silicone Implants.

    PubMed

    Chung, Kyu Jin; Park, Ki Rin; Lee, Jun Ho; Kim, Tae Gon; Kim, Yong-Ha

    2016-08-01

    Capsular fibrosis and contracture occurs in most breast reconstruction patients who undergo radiotherapy, and there is no definitive solution for its prevention. Simvastatin was effective at reducing fibrosis in various models. Peri-implant capsular formation is the result of tissue fibrosis development in irradiated breasts. The purpose of this study was to examine the effect of simvastatin on peri-implant fibrosis in rats. Eighteen male Sprague-Dawley rats were allocated to an experimental group (9 rats, 18 implants) or a control group (9 rats, 18 implants). Two hemispherical silicone implants, 10 mm in diameter, were inserted in subpanniculus pockets in each rat. The next day, 10-Gy of radiation from a clinical accelerator was targeted at the implants. Simvastatin (15 mg/kg/day) was administered by oral gavage in the experimental group, while animals in the control group received water. At 12 weeks post-implantation, peri-implant capsules were harvested and examined histologically and by real-time polymerase chain reaction. The average capsular thickness was 371.2 μm in the simvastatin group and 491.2 μm in the control group. The fibrosis ratio was significantly different, with 32.33% in the simvastatin group and 58.44% in the control group (P < 0.001). Connective tissue growth factor (CTGF) and transforming growth factor (TGF)-β1 gene expression decreased significantly in the simvastatin group compared to the control group (P < 0.001). This study shows that simvastatin reduces radiation-induced capsular fibrosis around silicone implants in rats. This finding offers an alternative therapeutic strategy for reducing capsular fibrosis and contracture after implant-based breast reconstruction.

  20. Simvastatin Reduces Capsular Fibrosis around Silicone Implants

    PubMed Central

    2016-01-01

    Capsular fibrosis and contracture occurs in most breast reconstruction patients who undergo radiotherapy, and there is no definitive solution for its prevention. Simvastatin was effective at reducing fibrosis in various models. Peri-implant capsular formation is the result of tissue fibrosis development in irradiated breasts. The purpose of this study was to examine the effect of simvastatin on peri-implant fibrosis in rats. Eighteen male Sprague-Dawley rats were allocated to an experimental group (9 rats, 18 implants) or a control group (9 rats, 18 implants). Two hemispherical silicone implants, 10 mm in diameter, were inserted in subpanniculus pockets in each rat. The next day, 10-Gy of radiation from a clinical accelerator was targeted at the implants. Simvastatin (15 mg/kg/day) was administered by oral gavage in the experimental group, while animals in the control group received water. At 12 weeks post-implantation, peri-implant capsules were harvested and examined histologically and by real-time polymerase chain reaction. The average capsular thickness was 371.2 μm in the simvastatin group and 491.2 μm in the control group. The fibrosis ratio was significantly different, with 32.33% in the simvastatin group and 58.44% in the control group (P < 0.001). Connective tissue growth factor (CTGF) and transforming growth factor (TGF)-β1 gene expression decreased significantly in the simvastatin group compared to the control group (P < 0.001). This study shows that simvastatin reduces radiation-induced capsular fibrosis around silicone implants in rats. This finding offers an alternative therapeutic strategy for reducing capsular fibrosis and contracture after implant-based breast reconstruction. PMID:27478339

  1. Putatively novel serotypes and the potential for reduced vaccine effectiveness: capsular locus diversity revealed among 5405 pneumococcal genomes

    PubMed Central

    van Tonder, Andries J.; Bray, James E.; Quirk, Sigríður J.; Haraldsson, Gunnsteinn; Jolley, Keith A.; Maiden, Martin C. J.; Hoffmann, Steen; Bentley, Stephen D.; Haraldsson, Ásgeir; Erlendsdóttir, Helga; Kristinsson, Karl G.; Brueggemann, Angela B.

    2017-01-01

    The pneumococcus is a leading global pathogen and a key virulence factor possessed by the majority of pneumococci is an antigenic polysaccharide capsule (‘serotype’), which is encoded by the capsular (cps) locus. Approximately 100 different serotypes are known, but the extent of sequence diversity within the cps loci of individual serotypes is not well understood. Investigating serotype-specific sequence variation is crucial to the design of sequence-based serotyping methodology, understanding pneumococcal conjugate vaccine (PCV) effectiveness and the design of future PCVs. The availability of large genome datasets makes it possible to assess population-level variation among pneumococcal serotypes and in this study 5405 pneumococcal genomes were used to investigate cps locus diversity among 49 different serotypes. Pneumococci had been recovered between 1916 and 2014 from people of all ages living in 51 countries. Serotypes were deduced bioinformatically, cps locus sequences were extracted and variation was assessed within the cps locus, in the context of pneumococcal genetic lineages. Overall, cps locus sequence diversity varied markedly: low to moderate diversity was revealed among serogroups/types 1, 3, 7, 9, 11 and 22; whereas serogroups/types 6, 19, 23, 14, 15, 18, 33 and 35 displayed high diversity. Putative novel and/or hybrid cps loci were identified among all serogroups/types apart from 1, 3 and 9. This study demonstrated that cps locus sequence diversity varied widely between serogroups/types. Investigation of the biochemical structure of the polysaccharide capsule of major variants, particularly PCV-related serotypes and those that appear to be novel or hybrids, is warranted. PMID:28133541

  2. Structure-property relationships in self-assembling peptide hydrogels, homopolypeptides and polysaccharides

    NASA Astrophysics Data System (ADS)

    Hule, Rohan A.

    The main objective of this dissertation is to investigate quantitative structure-property relationships in a variety of molecular systems including de novo designed peptides, peptide amphiphiles, polysaccharides and high molecular weight polypeptides. Peptide molecules consisting of 20 amino acids were designed to undergo thermally triggered intramolecular folding into asymmetric beta-hairpins and intermolecular self-assembly via a strand swapping mechanism into physically crosslinked fibrillar hydrogels. The self-assembly mechanism was confirmed by multiple characterization techniques such as circular dichroism and FITR spectroscopy, atomic force and transmission electron microscopy and small angle neutron scattering. Three distinct fibrillar nanostructures, i.e. non-twisted, twisted and laminated were produced, depending on the degree of strand asymmetry and peptide registry. Differences in the fibrillar morphology have a direct consequence on the mechanical properties of the hydrogels, with the laminated hydrogels exhibiting a significantly higher elastic modulus as compared to the twisted or non-twisted fibrillar hydrogels. SANS and cryo-TEM data reveal that the self-assembled fibrils form networks that are fractal in nature. Models employed to elucidate the fractal behavior can relate changes in the correlation lengths, low q (network), and high q (fibrillar) fractal exponents to the distinct fibrillar nanomorphology. The fractal dimension of the networks varies significantly, from a mass to a surface fractal and can be directly related to the local fibrillar morphology and changes in the peptide concentration. Transitions in the fractal behavior seen in the high q regime can be attributed to self-assembly kinetics. An identical model can be used to establish a direct correlation between the bulk properties and changes in both, the network density and underlying morphology, of a modified peptide-based hydrogel. As in the case of asymmetric peptides, changes in

  3. Involvement of exo5 in production of surface polysaccharides in Rhizobium leguminosarum and its role in nodulation of Vicia sativa subsp. nigra.

    PubMed

    Laus, Marc C; Logman, Trudy J; Van Brussel, Anton A N; Carlson, Russell W; Azadi, Parastoo; Gao, Mu-Yun; Kijne, Jan W

    2004-10-01

    Analysis of two exopolysaccharide-deficient mutants of Rhizobium leguminosarum, RBL5808 and RBL5812, revealed independent Tn5 transposon integrations in a single gene, designated exo5. As judged from structural and functional homology, this gene encodes a UDP-glucose dehydrogenase responsible for the oxidation of UDP-glucose to UDP-glucuronic acid. A mutation in exo5 affects all glucuronic acid-containing polysaccharides and, consequently, all galacturonic acid-containing polysaccharides. Exo5-deficient rhizobia do not produce extracellular polysaccharide (EPS) or capsular polysaccharide (CPS), both of which contain glucuronic acid. Carbohydrate composition analysis and nuclear magnetic resonance studies demonstrated that EPS and CPS from the parent strain have very similar structures. Lipopolysaccharide (LPS) molecules produced by the mutant strains are deficient in galacturonic acid, which is normally present in the core and lipid A portions of the LPS. The sensitivity of exo5 mutant rhizobia to hydrophobic compounds shows the involvement of the galacturonic acid residues in the outer membrane structure. Nodulation studies with Vicia sativa subsp. nigra showed that exo5 mutant rhizobia are impaired in successful infection thread colonization. This is caused by strong agglutination of EPS-deficient bacteria in the root hair curl. Root infection could be restored by simultaneous inoculation with a Nod factor-defective strain which retained the ability to produce EPS and CPS. However, in this case colonization of the nodule tissue was impaired.

  4. Capsular Management in Hip Arthroscopy: An Anatomic, Biomechanical, and Technical Review

    PubMed Central

    Kuhns, Benjamin D.; Weber, Alexander E.; Levy, David M.; Bedi, Asheesh; Mather, Richard C.; Salata, Michael J.; Nho, Shane J.

    2016-01-01

    Hip arthroscopy has become an increasingly utilized surgical technique for the treatment of the young, active patients with hip pain. The clinical outcomes of hip arthroscopy in this patient population have been largely successful; however, there is increasing interest in the contribution of hip capsule in postoperative clinical and functional outcomes. The structure and function of the normal hip capsule will be reviewed. Capsular contributions to hip stability will be discussed in the setting of hip arthroscopy with an emphasis on diagnosis-based considerations. Lastly, clinical outcomes following hip arthroscopy will be discussed as they relate to capsular management. PMID:26973840

  5. The molecular basis of polysaccharide cleavage by lytic polysaccharide monooxygenases

    PubMed Central

    Frandsen, Kristian E. H.; Simmons, Thomas J.; Dupree, Paul; Poulsen, Jens-Christian N.; Hemsworth, Glyn R.; Ciano, Luisa; Johnston, Esther M.; Tovborg, Morten; Johansen, Katja S.; von Freiesleben, Pernille; Marmuse, Laurence; Fort, Sébastien; Cottaz, Sylvain; Driguez, Hugues; Henrissat, Bernard; Lenfant, Nicolas; Tuna, Floriana; Baldansuren, Amgalanbaatar; Davies, Gideon J.; Leggio, Leila Lo; Walton, Paul H.

    2016-01-01

    Lytic polysaccharide monooxygenases (LPMOs) are copper-containing enzymes which oxidatively break down recalcitrant polysaccharides such as cellulose and chitin. Since their discovery LPMOs have become integral factors in the industrial utilization of biomass, especially in the sustainable generation of cellulosic bioethanol. We report here the first structural determination of an LPMO–oligosaccharide complex, yielding detailed insights into the mechanism of action of these enzymes. Using a combination of structure and electron paramagnetic resonance spectroscopy, we reveal the means by which LPMOs interact with saccharide substrates. We further uncover electronic and structural features of the enzyme active site, showing how LPMOs orchestrate the reaction of oxygen with polysaccharide chains. PMID:26928935

  6. Capsule of Cryptococcus neoformans grows by enlargement of polysaccharide molecules

    PubMed Central

    Frases, Susana; Pontes, Bruno; Nimrichter, Leonardo; Viana, Nathan B.; Rodrigues, Marcio L.; Casadevall, Arturo

    2009-01-01

    The human pathogenic fungus Cryptococcus neoformans has a distinctive polysaccharide (PS) capsule that enlarges during infection. The capsule is essential for virulence, but the mechanism for capsular growth is unknown. In the present study, we used dynamic light scattering (LS) analysis of capsular PS and optical tweezers (OT) to explore the architecture of the capsule. Analysis of capsular PS from cells with small and large capsules by dynamic LS revealed a linear correlation between PS effective diameter and microscopic capsular diameter. This result implied that capsule growth was achieved by the addition of molecules with larger effective diameter, such that some molecules can span the entire diameter of the capsule. Measurement of polystyrene bead penetration of C. neoformans capsules by using OT techniques revealed that the outer regions were penetrable, but not the inner regions. Our results provide a mechanism for capsular enlargement based on the axial lengthening of PS molecules and suggest a model for the architecture of a eukaryotic microbial capsule. PMID:19164571

  7. Solid-state NMR investigations of cellulose structure and interactions with matrix polysaccharides in plant primary cell walls.

    PubMed

    Wang, Tuo; Hong, Mei

    2016-01-01

    Until recently, the 3D architecture of plant cell walls was poorly understood due to the lack of high-resolution techniques for characterizing the molecular structure, dynamics, and intermolecular interactions of the wall polysaccharides in these insoluble biomolecular mixtures. We introduced multidimensional solid-state NMR (SSNMR) spectroscopy, coupled with (13)C labelling of whole plants, to determine the spatial arrangements of macromolecules in near-native plant cell walls. Here we review key evidence from 2D and 3D correlation NMR spectra that show relatively few cellulose-hemicellulose cross peaks but many cellulose-pectin cross peaks, indicating that cellulose microfibrils are not extensively coated by hemicellulose and all three major polysaccharides exist in a single network rather than two separate networks as previously proposed. The number of glucan chains in the primary-wall cellulose microfibrils has been under active debate recently. We show detailed analysis of quantitative (13)C SSNMR spectra of cellulose in various wild-type (WT) and mutant Arabidopsis and Brachypodium primary cell walls, which consistently indicate that primary-wall cellulose microfibrils contain at least 24 glucan chains.

  8. Structure of an abequose-containing O-polysaccharide from Citrobacter freundii O22 strain PCM 1555.

    PubMed

    Katzenellenbogen, Ewa; Kocharova, Nina A; Toukach, Philip V; Górska, Sabina; Korzeniowska-Kowal, Agnieszka; Bogulska, Maria; Gamian, Andrzej; Knirel, Yuriy A

    2009-09-08

    The lipopolysaccharide of Citrobacter freundii O22 (strain PCM 1555) was degraded under mild acidic conditions and the O-polysaccharide released was isolated by gel chromatography. Sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including two-dimensional (1)H,(1)H ROESY and (1)H,(13)C HMBC experiments, showed that the repeating unit of the O-polysaccharide has the following structure: alpha-Abep 1 -->3 --> 2)-alpha-D-Manp-(1-->4)-alpha-L-Rhap-(1-->3)-alpha-D-Galp-(1--> where Abe is abequose (3,6-dideoxy-D-xylo-hexose). SDS-PAGE and immunoblotting revealed that the O-antigen of C. freundii O22 is serologically indistinguishable from those of Salmonella group B serovars (Typhimurium, Brandenburg, Sandiego, Paratyphi B) but not related to other abequose-containing O-antigens tested (Citrobacter werkmanii O38 and Salmonella Kentucky) or colitose (l enantiomer of abequose)-containing O-antigen of Escherichia coli O111.

  9. Structural characterization of oligosaccharides and polysaccharides from apple juices produced by enzymatic pomace liquefaction.

    PubMed

    Mehrländer, Katri; Dietrich, Helmut; Sembries, Sabine; Dongowski, Gerhard; Will, Frank

    2002-02-27

    Eight apple pomace liquefaction juices were produced to characterize soluble cell wall material released by the action of pectolytic and cellulolytic enzyme preparations. Very high colloid values from 9.7 to 19.6 g/L were recovered from the juices by ethanol precipitation. The crude polysaccharides consisted mainly of galacturonic acid (49-64 mol %), arabinose (14-23 mol %), galactose (6-15 mol %), and minor amounts of rhamnose, xylose, and glucose. Separation of the polysaccharides by anion-exchange chromatography yielded one neutral, one slightly acidic, and one acidic polymer accounting for 60% of total colloids. Preparative size exclusion chromatography of the acidic fractions resulted in four polymers of different molecular weights and different sugar compositions. Among them, high molecular weight arabinans and rhamnogalacturonans as well as oligomeric fractions consisting of only galacturonic acid could be found. Linkage studies were performed on neutral fractions from anion-exchange chromatography and size exclusion chromatography. They revealed highly branched arabinans, xyloglucans, and mainly type I arabinogalactans.

  10. Structure, cell wall elasticity and polysaccharide properties of living yeast cells, as probed by AFM

    NASA Astrophysics Data System (ADS)

    Alsteens, David; Dupres, Vincent; McEvoy, Kevin; Wildling, Linda; Gruber, Hermann J.; Dufrêne, Yves F.

    2008-09-01

    Although the chemical composition of yeast cell walls is known, the organization, assembly, and interactions of the various macromolecules remain poorly understood. Here, we used in situ atomic force microscopy (AFM) in three different modes to probe the ultrastructure, cell wall elasticity and polymer properties of two brewing yeast strains, i.e. Saccharomyces carlsbergensis and S. cerevisiae. Topographic images of the two strains revealed smooth and homogeneous cell surfaces, and the presence of circular bud scars on dividing cells. Nanomechanical measurements demonstrated that the cell wall elasticity of S. carlsbergensis is homogeneous. By contrast, the bud scar of S. cerevisiae was found to be stiffer than the cell wall, presumably due to the accumulation of chitin. Notably, single molecule force spectroscopy with lectin-modified tips revealed major differences in polysaccharide properties of the two strains. Polysaccharides were clearly more extended on S. cerevisiae, suggesting that not only oligosaccharides, but also polypeptide chains of the mannoproteins were stretched. Consistent with earlier cell surface analyses, these findings may explain the very different aggregation properties of the two organisms. This study demonstrates the power of using multiple complementary AFM modalities for probing the organization and interactions of the various macromolecules of microbial cell walls.

  11. Structural characterization and antiviral effect of a novel polysaccharide PSP-2B from Prunellae Spica.

    PubMed

    Ma, Feng-Wei; Kong, Si-Yuan; Tan, Hong-Sheng; Wu, Rong; Xia, Bing; Zhou, Yan; Xu, Hong-Xi

    2016-11-05

    In the present study, a novel polysaccharide, PSP-2B, was isolated from aqueous extracts of Prunellae Spica by direct ultrafiltration membrane separation and gel chromatography purification. PSP-2B is a partially sulphated polysaccharide with a molecular weight of approximately 32kDa. Its sulfate content is 10.59% by elemental analysis. The major sugars comprising PSP-2B are arabinose, galactose and mannose, in addition to small amounts of glucose and uronic acids. The framework of PSP-2B is speculated to be a branched arabinogalactomannan, and the side chains are terminated primarily by the Araf residues. PSP-2B also contains 2.98% protein. PSP-2B exhibits activity against herpes simplex virus (HSV), with a half maximal inhibitory concentration (IC50) of approximately 69μg/mL for HSV-1 and 49μg/mL for HSV-2. However, PSP-2B demonstrated no cytotoxicity even when its concentration was increased to 1600μg/mL, suggesting that it has potential as an anti-HSV drug candidate.

  12. Isolation, purification, and structural features of a polysaccharide from Phellinus linteus and its hypoglycemic effect in alloxan-induced diabetic mice.

    PubMed

    Zhao, Chao; Liao, Zunsheng; Wu, Xiaoqi; Liu, Yanling; Liu, Xiaoyan; Lin, Zhanxi; Huang, Yifan; Liu, Bin

    2014-05-01

    Phellinus linteus is a medicinal mushroom that has been used in Oriental countries for centuries for its antitumor, antioxidant, immunomodulatory, and biological activity on hyperglycemia. A water-soluble crude polysaccharide was extracted using hot water from P. linteus mycelia grown under submerged culture. An orthogonal experiment was used to optimize the extraction conditions of P. linteus mycelia polysaccharides (PLP). The crude polysaccharide was purified using DEAE Sephadex A-50 and Sephadex G-200 chromatography. Fourier transform infrared (FT-IR) spectroscopy and nuclear magnetic resonance ((1) H NMR) spectroscopy were used to investigate the structure of the purified P. linteus polysaccharide (PLP-I), revealing that it was mainly a branched-type glycan with both α- and β-linkages and a pyranoid sugar ring conformation. PLP orally administered at 100 mg/kg body weight/d could significantly reduce the blood glucose level by 35.60% in alloxan-induced diabetic mice. The results of an oral glucose tolerance test (OGTT) revealed that PLP had an effect on glucose disposal after 28 d of treatment. The result revealed that PLP from a submerged culture of P. linteus mycelia possessed potent hypoglycemic properties. The polysaccharide may be useful as a functional food additive and a hypoglycemic agent.

  13. A Monoclonal Antibody to Cryptococcus neoformans Glucuronoxylomannan Manifests Hydrolytic Activity for Both Peptides and Polysaccharides.

    PubMed

    Bowen, Anthony; Wear, Maggie P; Cordero, Radames J B; Oscarson, Stefan; Casadevall, Arturo

    2017-01-13

    Studies in the 1980s first showed that some natural antibodies were "catalytic" and able to hydrolyze peptide or phosphodiester bonds in antigens. Many naturally occurring catalytic antibodies have since been isolated from human sera and associated with positive and negative outcomes in autoimmune disease and infection. The function and prevalence of these antibodies, however, remain unclear. A previous study suggested that the 18B7 monoclonal antibody against glucuronoxylomannan (GXM), the major component of the Cryptococcus neoformans polysaccharide capsule, hydrolyzed a peptide antigen mimetic. Using mass spectrometry and Förster resonance energy transfer techniques, we confirm and characterize the hydrolytic activity of 18B7 against peptide mimetics and show that 18B7 is able to hydrolyze an oligosaccharide substrate, providing the first example of a naturally occurring catalytic antibody for polysaccharides. Additionally, we show that the catalytic 18B7 antibody increases release of capsular polysaccharide from fungal cells. A serine protease inhibitor blocked peptide and oligosaccharide hydrolysis by 18B7, and a putative serine protease-like active site was identified in the light chain variable region of the antibody. An algorithm was developed to detect similar sites present in unique antibody structures in the Protein Data Bank. The putative site was found in 14 of 63 (22.2%) catalytic antibody structures and 119 of 1602 (7.4%) antibodies with no annotation of catalytic activity. The ability of many antibodies to cleave antigen, albeit slowly, supports the notion that this activity is an important immunoglobulin function in host defense. The discovery of GXM hydrolytic activity suggests new therapeutic possibilities for polysaccharide-binding antibodies.

  14. Structural features and water holding capacities of pressed potato fibre polysaccharides.

    PubMed

    Ramaswamy, Urmila R; Kabel, Mirjam A; Schols, Henk A; Gruppen, Harry

    2013-04-02

    Pressed potato fibre (PPF) has a high water holding capacity (WHC) affecting its processing as an animal feed. The aim of this study was to characterize cell wall polysaccharides (CWPs) in PPF and investigate their WHC. This was done via sequential extractions. Half of all CWPs were recovered in the hot buffer soluble solids extract as pectins (uronic acid and rhamnose) and galactans wherein most pectins (76%) from PPF were water soluble. Most likely, the network of CWPs is loosened during processing of potatoes. PPF showed a WHC of 7.4 expressed as the amount of water held per g of dry matter (mL/g). Reconstituting hot buffer soluble solids with buffer insoluble solids in water gave a WHC comparable to that of PPF. Removal of alkali soluble solids, which mainly comprised xyloglucans, lowered the WHC of the final residue. The results indicated that interactions between CWPs could affect the WHC of PPF.

  15. Structural characterisation and anti-ageing activity of extracellular polysaccharide from a strain of Lachnum sp.

    PubMed

    Ye, Ming; Chen, Wu-Xi; Qiu, Tao; Yuan, Ru-Yue; Ye, Ying-Wang; Cai, Jing-Min

    2012-05-01

    A homogeneous extracellular polysaccharide of Lachnum YM261(LEPS-1) with a molecular weight of 21670Da was characterised. According to HPGPC, IR, periodate oxidation and Smith degradation, GC-MS and (1)H NMR analysis, the results indicated that LEPS-1 was a glucan linked by the β-(1→3)-d-pyran glycosidic bond. The effect of LEPS-1 on anti-ageing in d-gal model mice was also studied. It was found that LEPS-1 significantly increased the activities of antioxidant enzymes (i.e. SOD superoxide dismutase, CAT catalase, GSH-PX glutathione peroxidase) and decreased malondialdehyde (MDA) content in liver, brain and serum of d-gal model mice. These results showed that LEPS-1 had a strong anti-ageing activity.

  16. [Etiopathogenesis and treatment of breast capsular contracture].

    PubMed

    Pereira Leite, Luis; Correia Sá, Inês; Marques, Marisa

    2013-01-01

    Introdução: A contractura capsular é a complicação crónica mais frequente da mamoplastia de aumento com próteses mamárias e a principal causa de insatisfação da doente e do cirurgião plástico. A cápsula mamária consiste num tecido fibroso que circunda a prótese e que pode contrair, alterando a forma e a consistência da mama. No estádio mais avançado é acompanhada de deformidade acentuada, rigidez e dor, tendo indicação para tratamento cirúrgico.Material e Métodos: Foram revistos todos os artigos indexados na PubMed através da pesquisa ‘capsular contracture’ (2000 - Janeiro 2012), dos quais foram inseridos os artigos de maior interesse em termos de etiologia, profilaxia e tratamento. Artigos referenciados em publicações relevantes foram também analisados.Resultados: Tudo indica que a sua etiologia é multifactorial; a etiopatogenia da contractura capsular mamária continua a ser alvo de múltipla investigação pré-clínica. Vários são os estudos realizados de forma a prevenir a ocorrência de contractura capsular e, embora os resultados sejam promissores, pouco está definido em termos da sua aplicação na prática clínica. Relativamente ao tratamento a capsulectomia/capsulotomia continua a ser o gold-standard, no entanto o futuro poderá passar por técnicas não invasivas, pelo menos em estádios mais leves da doença.Conclusão: Apesar das técnicas cirúrgicas e a qualidade das próteses mamárias terem vindo a melhorar drasticamente nos últimos anos, a contractura capsular mamária mantém-se uma complicação real, com incidência elevada e que continua a afectar milhares de mulheres no mundo.

  17. Effect of nonablative laser energy on joint capsular properties

    NASA Astrophysics Data System (ADS)

    Hayashi, Kei; Markel, Mark D.; Thabit, George, III; Bogdanske, John J.; Thielke, Robert J.

    1995-05-01

    Recent scientific studies evaluating laser energy for tissue welding and thermokeratoplasty have demonstrated that the application of laser energy at non-ablative levels can alter collagen's structural and biochemical properties. The application of non-ablative laser to the human shoulder joint capsule in patients with glenohumeral instability has been found to enhance stability of the joint. Based on the collective findings of these studies, we hypothesized that thermal modification of dense collagenous tissues such as joint capsule, ligament, and tendon can be achieved by applying non-ablative laser energy. The purpose of this study was to evaluate the effect of laser energy at non-ablative levels on joint capsular mechanical properties in an in vitro rabbit model. Twelve mature New Zealand white rabbits, ranging from 3.73 to 5.33 kg (4.49 +/- 0.44; mean +/- SD), were used for this experiment. Animals were euthanized and two 5 mm X 20 mm specimens were collected from the medial and lateral portion of the femoropatellar joint of each rabbit under a dissecting microscope; therefore four specimens were collected from each rabbit (right medial, right lateral, left medial, left lateral). Specimens were divided into four groups using a randomized block design; a control group and 3 laser power settings (5 watts (5 W), 10 watts (10 W), 15 watts (15 W)). Laser energy was applied using the Ho:YAG laser in four transverse passes across the tissue at a velocity of 2 mm/sec and distance from the tip of the handpiece to the synovial surface of the specimen set at 1.5 mm in a 37 degree(s)C tissue bath of lactated Ringer's solution. Forty-eight specimens (n equals 12) were mechanically tested to determine single cycle structural properties (stiffness) and viscoelastic properties (% relaxation) before and after laser treatment. Shrinkage of the tissue and the loads required to return specimens to their original length were recorded after laser treatment. The application of laser

  18. Structure of the O-polysaccharide and serological studies of the lipopolysaccharide of Proteus penneri 60 classified into a new Proteus serogroup O70.

    PubMed

    Zych, Krystyna; Perepelov, Andrei; Baranowska, Agata; Zabłotni, Agnieszka; Shashkov, Alexander S; Knirel, Yuriy A; Sidorczyk, Zygmunt

    2005-03-01

    An alkali-treated lipopolysaccharide of Proteus penneri strain 60 was studied by chemical analyses and 1H, 13C and 31P NMR spectroscopy, and the following structure of the linear pentasaccharide-phosphate repeating unit of the O-polysaccharide was established: 6)-alpha-D-Galp-(1-->3)-alpha-L-FucpNAc-(1-->3)-alpha-D-GlcpNAc-(1-->3)-beta-D-Quip4NAc-(1-->6)-alpha-D-Glcp-1-P-(O--> Rabbit polyclonal O-antiserum against P. penneri 60 reacted with both core and O-polysaccharide moieties of the homologous LPS. Based on the unique O-polysaccharide structure and serological data, we propose to classify P. penneri 60 into a new, separate Proteus serogroup O70. A weak cross-reactivity of P. penneri 60 O-antiserum with the lipopolysaccharide of Proteus vulgaris O8, O15 and O19 was observed and discussed in view of the chemical structures of the O-polysaccharides.

  19. Structural and Functional Analysis of a Lytic Polysaccharide Monooxygenase Important for Efficient Utilization of Chitin in Cellvibrio japonicus.

    PubMed

    Forsberg, Zarah; Nelson, Cassandra E; Dalhus, Bjørn; Mekasha, Sophanit; Loose, Jennifer S M; Crouch, Lucy I; Røhr, Åsmund K; Gardner, Jeffrey G; Eijsink, Vincent G H; Vaaje-Kolstad, Gustav

    2016-04-01

    Cellvibrio japonicusis a Gram-negative soil bacterium that is primarily known for its ability to degrade plant cell wall polysaccharides through utilization of an extensive repertoire of carbohydrate-active enzymes. Several putative chitin-degrading enzymes are also found among these carbohydrate-active enzymes, such as chitinases, chitobiases, and lytic polysaccharide monooxygenases (LPMOs). In this study, we have characterized the chitin-active LPMO,CjLPMO10A, a tri-modular enzyme containing a catalytic family AA10 LPMO module, a family 5 chitin-binding module, and a C-terminal unclassified module of unknown function. Characterization of the latter module revealed tight and specific binding to chitin, thereby unraveling a new family of chitin-binding modules (classified as CBM73). X-ray crystallographic elucidation of theCjLPMO10A catalytic module revealed that the active site of the enzyme combines structural features previously only observed in either cellulose or chitin-active LPMO10s. Analysis of the copper-binding site by EPR showed a signal signature more similar to those observed for cellulose-cleaving LPMOs. The full-length LPMO shows no activity toward cellulose but is able to bind and cleave both α- and β-chitin. Removal of the chitin-binding modules reduced LPMO activity toward α-chitin compared with the full-length enzyme. Interestingly, the full-length enzyme and the individual catalytic LPMO module boosted the activity of an endochitinase equally well, also yielding similar amounts of oxidized products. Finally, gene deletion studies show thatCjLPMO10A is needed byC. japonicusto obtain efficient growth on both purified chitin and crab shell particles.

  20. Structure and anti-influenza A (H1N1) virus activity of three polysaccharides from Eucheuma denticulatum

    NASA Astrophysics Data System (ADS)

    Yu, Guangli; Li, Miaomiao; Wang, Wei; Liu, Xin; Zhao, Xiaoliang; Lv, Youjing; Li, Guangsheng; Jiao, Guangling; Zhao, Xia

    2012-12-01

    Three polysaccharides (EW, EH and EA) were prepared from a red alga Eucheuma denticulatum by sequential extraction with cold water, hot water and sodium hydroxide water solution. Their monosaccharide compositions, relative molecular mass and structural characterization were determined by gas chromatography, high performance 1iquid chromatography, fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy methods. EW was hybrid ı/κ/ν-carrageenan (70 ı/17κ/13ν-carrabiose), EH was mainly ı-carrageenan, and EA was mainly α-1,4-Glucan (88%) but mixed with small amount of ı-carrageenan (12%). The relative molecular mass of EW, EH and EA was 480, 580 and 510 kDa, respectively. The anti-influenza A (H1N1) virus activity of these three polysaccharides was evaluated using the Madin-Darby canine kidney cells model. EW showed good anti-H1N1 virus activity, its IC50 was 276.5 μg mL-1, and the inhibition rate to H1N1 virus was 52% when its concentration was 250 μg mL-1. The IC50 of ı-carrageenan EH was 366.4 μg mL-1, whereas EA showed lower anti-H1N1 virus activity (IC50>430 μg mL-1). Available data obtained give positive evidence that the hybrid carrageenan EW from Eucheuma denticulatum can be used as potential anti-H1N1 virus inhibitor in future.

  1. Structural and Functional Analysis of a Lytic Polysaccharide Monooxygenase Important for Efficient Utilization of Chitin in Cellvibrio japonicus*

    PubMed Central

    Forsberg, Zarah; Nelson, Cassandra E.; Dalhus, Bjørn; Mekasha, Sophanit; Loose, Jennifer S. M.; Crouch, Lucy I.; Røhr, Åsmund K.; Gardner, Jeffrey G.; Eijsink, Vincent G. H.; Vaaje-Kolstad, Gustav

    2016-01-01

    Cellvibrio japonicus is a Gram-negative soil bacterium that is primarily known for its ability to degrade plant cell wall polysaccharides through utilization of an extensive repertoire of carbohydrate-active enzymes. Several putative chitin-degrading enzymes are also found among these carbohydrate-active enzymes, such as chitinases, chitobiases, and lytic polysaccharide monooxygenases (LPMOs). In this study, we have characterized the chitin-active LPMO, CjLPMO10A, a tri-modular enzyme containing a catalytic family AA10 LPMO module, a family 5 chitin-binding module, and a C-terminal unclassified module of unknown function. Characterization of the latter module revealed tight and specific binding to chitin, thereby unraveling a new family of chitin-binding modules (classified as CBM73). X-ray crystallographic elucidation of the CjLPMO10A catalytic module revealed that the active site of the enzyme combines structural features previously only observed in either cellulose or chitin-active LPMO10s. Analysis of the copper-binding site by EPR showed a signal signature more similar to those observed for cellulose-cleaving LPMOs. The full-length LPMO shows no activity toward cellulose but is able to bind and cleave both α- and β-chitin. Removal of the chitin-binding modules reduced LPMO activity toward α-chitin compared with the full-length enzyme. Interestingly, the full-length enzyme and the individual catalytic LPMO module boosted the activity of an endochitinase equally well, also yielding similar amounts of oxidized products. Finally, gene deletion studies show that CjLPMO10A is needed by C. japonicus to obtain efficient growth on both purified chitin and crab shell particles. PMID:26858252

  2. Traumatic Extra-capsular and Intra-capsular Floating Fat: Fat-fluid Levels of the Knee Revisited

    PubMed Central

    Davis, Derik L; Vachhani, Prasann

    2015-01-01

    Floating fat is a sign of acute bone injury at the knee following trauma. The goal of this article is to review the etiology, patterns, and mimickers of extra-capsular and intra-capsular floating fat, with the major emphasis on knee trauma in the acute setting. We will discuss the spectrum of multimodal imaging findings for rare presentations of extra-capsular floating fat, and contrast these with common and atypical forms of intra-capsular lipohemarthrosis, as an aid to the assessment of acute bone trauma at the knee. PMID:26713176

  3. Structural characterization and in vitro inhibitory activities in P-selectin-mediated leukocyte adhesion of polysaccharide fractions isolated from the roots of Physalis alkekengi.

    PubMed

    Tong, Haibin; Wang, Ruifei; Liu, Ximing; Wang, Guiyun; Du, Fengguo; Zeng, Xianlu

    2011-08-01

    Selectin-mediated leukocyte initial attachment and rolling over vessel endothelial surface are crucial steps for inflammatory responses. As P-selectin is a promising target for anti-inflammation therapeutic strategy, recent works have focused on searching for more potent and non-toxic P-selectin antagonists among various natural carbohydrate products. Here, we isolated three water-soluble polysaccharide fractions (PPS-1, PPS-2 and PPS-3) from the roots of Physalis alkekengi by DEAE-cellulose and Sephacryl S-200 chromatography. Their physicochemical and structural characterizations were determined by chemical methods, GC (gas chromatography), HPLC (high performance liquid chromatography), FT-IR (Fourier transform infrared spectrometry), partial acid hydrolysis, methylation and GC-MS (gas chromatography-mass spectrometry) analyses. The inhibitory capacity of the polysaccharide fractions in P-selectin-mediated leukocyte adhesion was evaluated by flow cytometric, static adhesion and laminar flow assays. Results showed that different polysaccharide fractions possess distinct physicochemical and structural properties, including carbohydrate, protein and uronic acid contents, molecular weight, monosaccharide composition and glycosidic linkage type. Among the polysaccharide fractions, PPS-2 could effectively block the interaction between P-selectin and its native ligand.

  4. Structural Elements and Cough Suppressing Activity of Polysaccharides from Zingiber officinale Rhizome.

    PubMed

    Bera, K; Nosalova, G; Sivova, V; Ray, B

    2016-01-01

    Zingiber officinale is used for the management of fever, bronchial asthma and cough for thousands of years. While the link to a particular indication has been established in human, the active principle of the formulation remains unknown. Herein, we have investigated a water extracted polysaccharides (WEP) containing fraction from its rhizome. Utilizing a traditional aqueous extraction protocol and using chemical, chromatographic and spectroscopic methods a fraction containing a branched glucan and polygalaturonan in a ratio of 59:1 was characterized. This glucan, which has a molecular mass of 36 kDa, is made up of terminal-, (1,4)- and (1,4,6)-linked α-Glcp residues. Oral administration of WEP in doses of 25 and 50 mg/kg body weight significantly inhibited the number of citric acid-induced cough efforts in guinea pigs. It does not alter the specific airway smooth muscle reactivity significantly. Thus, traditional aqueous extraction method provides molecular entities, which induces antitussive activity without addiction.

  5. Nanohybrid structure analysis and biomolecule release behavior of polysaccharide-CDHA drug carriers

    NASA Astrophysics Data System (ADS)

    Huang, Li-Ying; Liu, Ting-Yu; Liu, Tse-Ying; Mevold, Andreas; Hardiansyah, Andri; Liao, Hung-Chou; Lin, Chin-Ching; Yang, Ming-Chien

    2013-10-01

    Nanoscaled polymer composites were prepared from polysaccharide chitosan (CS) and Ca-deficient hydroxyapatite (CDHA). CS-CDHA nanocomposites were synthesized by in situ precipitation at pH 9, and the CS-CDHA carriers were then fabricated by ionic cross-linking methods using tripolyphosphate and chemical cross-linking methods by glutaraldehyde and genipin. Certain biomolecules such as vitamin B12, cytochrome c, and bovine serum albumin were loaded into the CS-CDHA carriers, and their release behaviors were investigated. Furthermore, these CS-CDHA carriers were examined by transmission electron microscopy, electron spectroscopy for chemical analysis, and X-ray diffraction. The release behavior of the biomolecules was controlled by the CS/CDHA ratios and cross-linked agents. By increasing the concentration of CS and the concentration of the cross-linking agents, cross-linking within carriers increases, and the release rate of the biomolecules is decreased. Moreover, the release rate of the biomolecules from the CS-CDHA carriers at pH 4 was higher than that at pH 10, displaying a pH-sensitive behavior. Therefore, these CS-CDHA hydrogel beads may be useful for intelligent drug release and accelerate bone reconstruction.

  6. Polysaccharide and extracts from Lentinula edodes: structural features and antiviral activity

    PubMed Central

    2012-01-01

    Background Lentinula edodes, known as shiitake, has been utilized as food, as well as, in popular medicine, moreover, compounds isolated from its mycelium and fruiting body have shown several therapeutic properties. The aim of this study was to determine the antiviral activity of aqueous (AqE) and ethanol (EtOHE) extracts and polysaccharide (LeP) from Lentinula edodes in the replication of poliovirus type 1 (PV-1) and bovine herpes virus type 1 (BoHV-1). Methods The time-of-addition assay was performed at the times -2, -1, 0, 1 and 2 h of the infection. The virucidal activity and the inhibition of viral adsorption were also evaluated. Plaque assay was used to monitor antiviral activity throughout. Results The AqE and LeP were more effective when added at 0 h of infection, however, EtOHE was more effective at the times 1 h and 2 h of the infection. AqE, EtOHE and LeP showed low virucidal activity, and the inhibition of viral adsorption was not significant. Conclusions The results allowed us to conclude that AqE, EtOHE and LeP act on the initial processes of the replication of both strains of virus. PMID:22336004

  7. Multiplex PCR for Identification of Two Capsular Types in Epidemic KPC-Producing Klebsiella pneumoniae Sequence Type 258 Strains

    PubMed Central

    Chen, Liang; Chavda, Kalyan D.; Findlay, Jacqueline; Peirano, Gisele; Hopkins, Katie; Pitout, Johann D. D.; Bonomo, Robert A.; Woodford, Neil; DeLeo, Frank R.

    2014-01-01

    We developed a multiplex PCR assay capable of identifying two capsular polysaccharide synthesis sequence types (sequence type 258 [ST258] cps-1 and cps-2) in epidemic Klebsiella pneumoniae ST258 strains. The assay performed with excellent sensitivity (100%) and specificity (100%) for identifying cps types in 60 ST258 K. pneumoniae sequenced isolates. The screening of 419 ST258 clonal isolates revealed a significant association between cps type and K. pneumoniae carbapenemase (KPC) variant: cps-1 is largely associated with KPC-2, while cps-2 is primarily associated with KPC-3. PMID:24733470

  8. Arthroscopic Capsular Release of the Ankle Joint.

    PubMed

    Lui, Tun Hing

    2016-12-01

    Adhesive capsulitis of the ankle is also known as frozen ankle and results in marked fibrosis and contracture of the ankle capsule. Arthroscopic capsular release is indicated for symptomatic frozen ankle that is resistant to conservative treatment. It is contraindicated for ankle stiffness due to degenerative joint disease, intra-articular malunion, or adhesion of the extensors of the ankle. The procedure consists of endoscopic posterior ankle capsulectomy and arthroscopic anterior ankle capsulotomy. It has the advantages of being minimally invasive surgery and allowing early postoperative vigorous mobilization of the ankle joint.

  9. Preparation, characterization, and immunogenicity of Haemophilus influenzae type b polysaccharide-protein conjugates

    PubMed Central

    1980-01-01

    A method is presented for covalently bonding Haemophilus influenzae type b capsular polysaccharide (HIB Ps) to several proteins. The method is efficient and relies upon the use of adipic dihydrazide as a spacer between the capsular polysaccharide and the carrier protein. In contrast to the poor immunogenicity of the purified HIB Ps in mice and rabbits, the HIB Ps-protein conjugates induced serum anti-type b antibodies having bactericidal activity at levels shown to be protective in humans when low doses were injected subcutaneously in a saline solution. The antibody response in mice was related to the dose of the conjugates, increased with the number of injections, and could be primed by the previous injection of the carrier protein. The HIB Ps- protein conjugates were immunogenic in three different mouse strains. The importance of the carrier molecule for the enhanced immunogenicity of the HIB Ps-protein conjugates was shown by the failure of HIB Ps hybrids prepared with either the homologous polysaccharide or pneumococcus type 3 polysaccharide to induce antibodie in mice. Rabbits injected with the HIB Ps-protein conjugates emulsified in Freund's adjuvant produced high levels of serum anti-type b antibodies which induced a bactericidal effect upon H. influenzae type b organisms. It is proposed that the HIB Ps component of the polysaccharide protein conjugates has been converted to a thymic-dependent immunogen. This method may be used to prepare protein-polysaccharide conjugates with HIB Ps and other polysaccharides to be considered for human use. PMID:6967514

  10. Polysaccharide Degradation

    NASA Astrophysics Data System (ADS)

    Stone, Bruce A.; Svensson, Birte; Collins, Michelle E.; Rastall, Robert A.

    An overview of current and potential enzymes used to degrade polysaccharides is presented. Such depolymerases are comprised of glycoside hydrolases, glycosyl transferases, phosphorylases and lyases, and their classification, active sites and action patterns are discussed. Additionally, the mechanisms that these enzymes use to cleave glycosidic linkages is reviewed as are inhibitors of depolymerase activity; reagents which react with amino acid residues, glycoside derivatives, transition state inhibitors and proteinaceous inhibitors. The characterization of various enzymes of microbial, animal or plant origin has led to their widespread use in the production of important oligosaccharides which can be incorporated into food stuffs. Sources of polysaccharides of particular interest in this chapter are those from plants and include inulin, dextran, xylan and pectin, as their hydrolysis products are purported to be functional foods in the context of gastrointestinal health. An alternative use of degraded polysaccharides is in the treatment of disease. The possibility exists to treat bacterial exopolysaccharide with lyases from bacteriophage to produce oligosaccharides exhibiting bioactive sequences. Although this area is currently in its infancy the knowledge is available to investigate further.

  11. The structure of the lipopolysaccharide O-chain (M antigen) and polysaccharide B produced by Brucella melitensis 16M.

    PubMed

    Bundle, D R; Cherwonogrodzky, J W; Perry, M B

    1987-06-01

    The surface M antigen of Brucella species has been identified as the lipopolysaccharide O-polysaccharide component composed of a repeating pentasaccharide unit containing a sequence of one 1,3- and four 1,2-linked, 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl units. A neutral polysaccharide produced by Brucella species and referred to as polysaccharide B (poly B) has been identified as a family of circular 1,2-linked polymers of beta-D-glucopyranosyl units ranging in ring size from 17 to 24 glucosyl units.

  12. Structural, thermal, and anti-inflammatory properties of a novel pectic polysaccharide from alfalfa (Medicago sativa L.) stem.

    PubMed

    Chen, Lei; Liu, Jie; Zhang, Yaqiong; Dai, Bona; An, Yuan; Yu, Liangli Lucy

    2015-04-01

    A pectic polysaccharide (APPS) was purified from the cold alkali extract of alfalfa stem and characterized to be a rhamnogalacturonan I (RG-I) type pectin with the molecular weight of 2.38 × 10(3) kDa and a radius of 123 nm. The primary structural analysis indicated that APPS composed of a →2)-α-l-Rhap-(1→4)-α-d-GalpA-(1→ backbone with 12% branching point at C-4 of Rhap forming side chains by l-arabinosyl and d-galactosyl oligosaccharide units. Transmission electron microscopy (TEM) analysis revealed a primary linear-shaped structure with a few branches in its assembly microstructures. The thermal decomposition evaluation revealed the stability of APPS with an apparent activation energy (Ea) of 226.5 kJ/mol and a pre-exponential factor (A) of 2.10 × 10(25)/s, whereas its primary degradation occurred in the temperature range from 215.6 to 328.0 °C. In addition, APPS showed significant anti-inflammatory effect against mRNA expressions of the pro-inflammatory cytokine genes, especially for IL-1β, suggesting its potential utilization in functional foods and dietary supplement products.

  13. Structure of the O-polysaccharide of Proteus penneri 28 and Proteus vulgaris O31 and classification of P. penneri 26 and 28 in Proteus serogroup O31.

    PubMed

    Kondakova, Anna N; Zych, Krystyna; Senchenkova, Sof'ya N; Bartodziejska, Beata; Shashkov, Alexander S; Knirel, Yuriy A; Rozalski, Antoni A; Sidorczyk, Zygmunt

    2003-10-24

    The lipopolysaccharides (LPS) of Proteus penneri 28 and Proteus vulgaris O31 (PrK 55/57) were degraded with dilute acetic acid and structurally identical high-molecular-mass O-polysaccharides were isolated by gel-permeation chromatography. Sugar analysis and nuclear magnetic resonance (NMR) spectroscopic studies showed that both polysaccharides contain D-GlcNAc, 2-acetamido-2,6-dideoxy-L-glucose (L-2-acetamido-2,6-dideoxyglucose (N-acetylquinovosamine)) and 2-acetamido-3-O-[(S)-1-carboxyethyl]-2-deoxy-D-glucose (N-acetylisomuramic acid) and have the following structure: [carbohydrate structure: see text] where (S)-1-carboxyethyl [a residue of (S)-lactic acid] (S-Lac) is an ether-linked residue of (S)-lactic acid. The O-polysaccharide studied is structurally similar to that of P. penneri 26, which differs only in the absence of S-Lac from the GlcNAc residue. Based on the O-polysaccharide structures and serological data of the LPS, it was suggested classifying these strains in one Proteus serogroup, O31, as two subgroups: O(31a), 31b for P. penneri 28 and P. vulgaris PrK 55/57 and O31a for P. penneri 26. A serological relatedness of the LPS of Proteus O(31a), 31b and P. penneri 62 was revealed and substantiated by sharing epitope O31b, which is associated with N-acetylisomuramic acid. It was suggested that a cross-reactivity of P. penneri 28 O-antiserum with the LPS of several other P. penneri strains is due to a common epitope(s) on the LPS core.

  14. Polysaccharides, mimotopes and vaccines for fungal and encapsulated pathogens.

    PubMed

    Pirofski, L A

    2001-09-01

    Vaccination is a rational alternative to treatment for Cryptococcus neoformans infections, as these infections are currently intractable in immunocompromised (including HIV-infected) individuals. Vaccines composed of the cryptococcal capsular polysaccharide glucuronoxylomannan (GXM), the key C. neoformans virulence factor, elicit protective antibodies in mice, although deleterious antibodies can also be induced. By contrast, polysaccharides are poor immunogens in HIV-infected humans and others with B-cell defects. Peptide mimotopes of GXM can induce protective immunity to C. neoformans in mice, however, our knowledge of the mechanisms of mimotope-induced protection is incomplete and further work is needed if polysaccharide- or mimotope-based vaccines are to be used to manage C. neoformans infection.

  15. EPS-I Polysaccharide Protects Mycoplasma pulmonis from Phagocytosis

    PubMed Central

    Shaw, Brandon M.; Daubenspeck, James M.; Simmons, Warren L.; Dybvig, Kevin

    2012-01-01

    Few mycoplasmal polysaccharides have been described and little is known about their role in pathogenesis. The infection of mice with Mycoplasma pulmonis has been utilized in many in vivo and in vitro studies to gain a better understanding of host-pathogen interactions during chronic respiratory infection. Although alveolar macrophages have a primary role in host defense, M. pulmonis is killed inefficiently in vitro. One antiphagocytic factor produced by the mycoplasma is the family of phase- and size-variable Vsa lipoproteins. However, bacteria generally employ multiple strategies for combating host defenses, with capsular polysaccharide often having a key role. We show here that mutants lacking the EPS-I polysaccharide of M. pulmonis exhibit increased susceptibility to binding and subsequent killing by alveolar macrophages. These results give further insight into how mycoplasmas are able to avoid the host immune system and sustain a chronic infection. PMID:23190331

  16. Structural and functional characterization of a small chitin-active lytic polysaccharide monooxygenase domain of a multi-modular chitinase from Jonesia denitrificans.

    PubMed

    Mekasha, Sophanit; Forsberg, Zarah; Dalhus, Bjørn; Bacik, John-Paul; Choudhary, Swati; Schmidt-Dannert, Claudia; Vaaje-Kolstad, Gustav; Eijsink, Vincent G H

    2016-01-01

    Lytic polysaccharide monooxygenases (LPMOs) boost enzymatic depolymerization of recalcitrant polysaccharides, such as chitin and cellulose. We have studied a chitin-active LPMO domain (JdLPMO10A) that is considerably smaller (15.5 kDa) than all structurally characterized LPMOs so far and that is part of a modular protein containing a GH18 chitinase. The 1.55 Å resolution structure revealed deletions of interacting loops that protrude from the core β-sandwich scaffold in larger LPMO10s. Despite these deletions, the enzyme is active on alpha- and beta-chitin, and the chitin-binding surface previously described for larger LPMOs is fully conserved. JdLPMO10A may represent a minimal scaffold needed to catalyse the powerful LPMO reaction.

  17. Physico-chemical properties of Salmonella typhi Vi polysaccharide-diphtheria toxoid conjugate vaccines affect immunogenicity.

    PubMed

    An, So Jung; Yoon, Yeon Kyung; Kothari, Sudeep; Kothari, Neha; Kim, Jeong Ah; Lee, Eugene; Kim, Deok Ryun; Park, Tai Hyun; Smith, Greg W; Carbis, Rodney

    2011-10-13

    In this study it was demonstrated that the immunogenicity of Vi polysaccharide-diphtheria toxoid conjugates was related to the physical and chemical structure of the conjugate. Conjugates were prepared in two steps, firstly binding adipic acid dihydrazide (ADH) spacer molecules to diphtheria toxoid (DT) carrier protein then secondly binding varying amounts of this derivatized DT to a fixed amount of Vi capsular polysaccharide purified from Salmonella enterica Serovar Typhi. As the amount of DT bound to the Vi increased the size of the conjugate increased but also the degree of cross-linking increased. The immunogenicity of the conjugates was tested in mice and measured by ELISA for anti Vi and anti DT IgG responses, and the results revealed a trend that as the amount of DT bound to the Vi increased the anti Vi responses increased. This study establishes a correlation between physico-chemical characteristics of the conjugate and the magnitude of the anti Vi and anti DT responses.

  18. Polysaccharide hydrogels with tunable stiffness and provasculogenic properties via α-helix to β-sheet switch in secondary structure

    PubMed Central

    Forget, Aurelien; Christensen, Jon; Lüdeke, Steffen; Kohler, Esther; Tobias, Simon; Matloubi, Maziar; Thomann, Ralf; Shastri, V. Prasad

    2013-01-01

    Mechanical aspects of the cellular environment can influence cell function, and in this context hydrogels can serve as an instructive matrix. Here we report that physicochemical properties of hydrogels derived from polysaccharides (agarose, κ-carrageenan) having an α-helical backbone can be tailored by inducing a switch in the secondary structure from α-helix to β-sheet through carboxylation. This enables the gel modulus to be tuned over four orders of magnitude (G′ 6 Pa–3.6 × 104 Pa) independently of polymer concentration and molecular weight. Using carboxylated agarose gels as a screening platform, we demonstrate that soft-carboxylated agarose provides a unique environment for the polarization of endothelial cells in the presence of soluble and bound signals, which notably does not occur in fibrin and collagen gels. Furthermore, endothelial cells organize into freestanding lumens over 100 μm in length. The finding that a biomaterial can modulate soluble and bound signals provides impetus for exploring mechanobiology paradigms in regenerative therapies. PMID:23886665

  19. Structural and serological studies on a new acidic O-specific polysaccharide of Proteus vulgaris O32.

    PubMed

    Bartodziejska, B; Shashkov, A S; Babicka, D; Grachev, A A; Torzewska, A; Paramonov, N A; Chernyak, A Y; Rozalski, A; Knirel, Y A

    1998-09-01

    The following structure of the O-specific polysaccharide chain (O-antigen) of the Proteus vulgaris 032 lipopolysaccharide (LPS) was established by 1H-NMR and 13C-NMR spectroscopy, including two-dimensional NOESY and H-detected 1H,13C heteronuclear multiple-quantum coherence (HMQC) experiments: -->2)-alpha-L-RhapI-(1-->2)-alpha-L-RhapII-(1-->4)-beta-D-++ +GalpA(I)-(1-->3)-beta-D-GlcpNAc-(1-->4)-alpha-D-GalpA(II)-(1-- >. In addition, an O-acetyl group was detected, which, most probably, is located at position 3 of a part of RhapI residues. Serological studies, using rabbit polyclonal anti-(P. vulgaris 032) serum, homologous and heterologous Proteus O-antigens and related artificial antigens, revealed the importance of an a-D-GalA-associated epitope in manifesting the immunospecificity of P. vulgaris 032 and substantiated serological relationships between the O-antigen studied and those of some other Proteus strains.

  20. Structural characterization and study of immunoenhancing and antioxidant property of a novel polysaccharide isolated from the aqueous extract of a somatic hybrid mushroom of Pleurotus florida and Calocybe indica variety APK2.

    PubMed

    Maity, Kousik; Kar Mandal, Eshita; Maity, Saikat; Gantait, Sanjoy K; Das, Debsankar; Maiti, Swatilekha; Maiti, Tapas K; Sikdar, Samir R; Islam, Syed S

    2011-03-01

    A water-soluble polysaccharide was isolated from the aqueous extract of the fruit bodies of somatic hybrid PCH9FB, obtained through intergeneric protoplast fusion between the strains Pleurotus florida and Calocybe indica var. On the basis of total acid hydrolysis, the polysaccharide was found to contain galactose, fucose, and glucose in a molar ratio of nearly 2:1:2. Methylation analysis and NMR experiments ((1)H, (13)C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC) showed that the structure of the repeating unit present in the polysaccharide was This molecule showed macrophage, splenocyte, thymocyte activation as well as antioxidant property.

  1. Structure of the O-polysaccharide from the lipopolysaccharide of Providencia stuartii O43 containing an amide of D-galacturonic acid with L-serine.

    PubMed

    Ovchinnikova, Olga G; Kocharova, Nina A; Torzewska, Agnieszka; Blaszczyk, Aleksandra; Shashkov, Alexander S; Knirel, Yuriy A; Rozalski, Antoni

    2005-05-23

    The O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Providencia stuartii O43:H28 and studied by sugar and methylation analyses, Smith degradation and 1H and 13C NMR spectroscopy, including 2D ROESY, and H-detected 1H, 13C HSQC and HMBC experiments, as well as a NOESY 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 tetrasaccharide repeating units containing an amide of D-galacturonic acid with L-serine [D-GalA6(L-Ser)] and has the following structure:[3)-beta-D-GalpA6(L-Ser)-(1-->3)-beta-D-GlcpNAc-(1-->2)-alpha-D-Rhap4NAc-(1-->4)-beta-D-GlcpA-(1-->]n.

  2. Structure of the O-specific polysaccharide of Proteus vulgaris O45 containing 3-acetamido-3,6-dideoxy-D-galactose.

    PubMed

    Perepelov, Andrei V; Bartodziejska, Beata; Senchenkova, Sof'ya N; Shashkov, Alexander S; Rozalski, Antoni; Knirel, Yuriy A

    2003-02-07

    An O-specific polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of Proteus vulgaris O45 and studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, ROESY, H-detected 1H,13C HSQC and HMBC experiments. The following structure of the pentasaccharide repeating unit of the polysaccharide was established:-->6)-alpha-D-GlcpNAc-(1-->4)-alpha-D-GalpNAc-(1-->4)-alpha-D-GalpA-(1-->3)-beta-D-GlcpNAc-(1-->2)-beta-D-Fucp3NAc4Ac-(1-->where Fuc3NAc4Ac is 3-acetamido-4-O-acetyl-3,6-dideoxygalactose. A cross-reactivity of anti-P. vulgaris O45 serum was observed with several other Proteus lipopolysaccharides, which contains Fuc3N derivatives.

  3. Unliganded and substrate bound structures of the cellooligosaccharide active lytic polysaccharide monooxygenase LsAA9A at low pH.

    PubMed

    Frandsen, Kristian E H; Poulsen, Jens-Christian N; Tandrup, Tobias; Lo Leggio, Leila

    2017-03-24

    Lytic polysaccharide monooxygenases (LPMOs) have been found to be key components in microbial (bacterial and fungal) degradation of biomass. They are copper metalloenzymes that degrade polysaccharides oxidatively and act in synergy with glycoside hydrolases. Recently crystallographic studies carried out at pH 5.5 of the LPMO from Lentinus similis belonging to the fungal LPMO family AA9 have provided the first atomic resolution view of substrate-LPMO interactions. The LsAA9A structure presented here determined at pH 3.5 shows significant disorder of the active site in the absence of substrate ligand. Furthermore some differences are also observed in regards to substrate (cellohexaose) binding, although the major interaction with the N-terminal histidine remains unchanged.

  4. Structure of a Kdo-containing O polysaccharide representing Proteus O79, a newly described serogroup for some clinical Proteus genomospecies isolates from Poland.

    PubMed

    Arbatsky, Nikolay P; Drzewiecka, Dominika; Palusiak, Agata; Shashkov, Alexander S; Zabłotni, Agnieszka; Siwińska, Małgorzata; Knirel, Yuriy A

    2013-09-20

    From 41 Proteus genomospecies strains isolated in Poland, seven displayed similar serospecificity in ELISA with intact and adsorbed O antisera as well as in Western blot. The cross-reacting strains were found to belong to Proteus genomospecies 5/6 and classified into a new Proteus serogroup, O79, which seems to be widespread among Proteus genomospecies clinical isolates in Lodz, Poland. The O polysaccharide of the lipopolysaccharide of a representative O79 strain, 11 B-r, was studied by chemical analyses and (1)H and (13)C NMR spectroscopy, and the following structure of the repeating unit was established: →4)-α-D-GlcpNAlaAc-(1→5)-α-Kdop-(2→2)-α-D-Glcp-(1→3)-β-D-GlcpNAc-(1→ where AlaAc indicates N-acetyl-L-alanyl and Kdo indicates 3-deoxy-D-manno-oct-2-ulosonic acid. The O polysaccharide was unstable under mild acidic conditions and cleaved by acid-labile linkages of Kdo residues to yield a tetrasaccharide with Kdo at the reducing end. The structure established is unique among Proteus O polysaccharides, which is in agreement with the lack of any significant cross-reactivity for the lipopolysaccharide of strain 11 B-r and O antisera against strains of all known Proteus O serogroups and vice versa.

  5. Structural and serological studies of the related O-specific polysaccharides of Proteus vulgaris O21 and Proteus mirabilis O48 having oligosaccharide-phosphate repeating units.

    PubMed

    Bartodziejska, B; Toukach, F V; Vinogradov, E V; Senchenkova, S N; Shashkov, A S; Ziolkowski, A; Czaja, J; Perry, M B; Knirel, Y A; Rozalski, A

    2000-12-01

    The O-specific polysaccharide chains (O-antigens) of the lipopolysaccharides (LPSs) of Proteus mirabilis O48 and Proteus vulgaris O21 were found to have tetrasaccharide and pentasaccharide repeating units, respectively, interlinked by a glycosidic phosphate. Polysaccharides and an oligosaccharide were derived from the LPSs by various degradation procedures and studied by 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, NOESY, H-detected 1H,13C and 1H,31P HMQC experiments. The following related structures of the repeating units of the O-antigens were established (top: Proteus mirabilis O48; bottom: Proteus vulgaris O21) The O-specific polysaccharide of P. vulgaris O21 has the same structure as that of Hafnia allvei 744 and PCM 1194 [Petersson C., Jachymek, W., Klonowska, A., Lugowski, C., Niedziela, T. & Kenne, L. (1997) Eur. J. Biochem., 245, 668-675], except that the GlcN residue carries the N-acetyl rather than the N-[(R)-3-hydroxybutyryl] group. Serological investigations confirmed the close relatedness of the Proteus and Hafnia O-antigens studied.

  6. Molecular characterization of a Penicillium chrysogenum exo-rhamnogalacturonan lyase that is structurally distinct from other polysaccharide lyase family proteins.

    PubMed

    Iwai, Marin; Kawakami, Takuya; Ikemoto, Takeshi; Fujiwara, Daisuke; Takenaka, Shigeo; Nakazawa, Masami; Ueda, Mitsuhiro; Sakamoto, Tatsuji

    2015-10-01

    We previously described an endo-acting rhamnogalacturonan (RG) lyase, termed PcRGL4A, of Penicillium chrysogenum 31B. Here, we describe a second RG lyase, called PcRGLX. We determined the cDNA sequence of the Pcrglx gene, which encodes PcRGLX. Based on analyses using a BLAST search and a conserved domain search, PcRGLX was found to be structurally distinct from known RG lyases and might belong to a new polysaccharide lyase family together with uncharacterized fungal proteins of Nectria haematococca, Aspergillus oryzae, and Fusarium oxysporum. The Pcrglx cDNA gene product (rPcRGLX) expressed in Escherichia coli demonstrated specific activity against RG but not against homogalacturonan. Divalent cations were not essential for the enzymatic activity of rPcRGLX. rPcRGLX mainly released unsaturated galacturonosyl rhamnose (ΔGR) from RG backbones used as the substrate from the initial stage of the reaction, indicating that the enzyme can be classified as an exo-acting RG lyase (EC 4.2.2.24). This is the first report of an RG lyase with this mode of action in Eukaryota. rPcRGLX acted synergistically with PcRGL4A to degrade soybean RG and released ΔGR. This ΔGR was partially decorated with galactose (Gal) residues, indicating that rPcRGLX preferred oligomeric RGs to polymeric RGs, that the enzyme did not require Gal decoration of RG backbones for degradation, and that the enzyme bypassed the Gal side chains of RG backbones. These characteristics of rPcRGLX might be useful in the determination of complex structures of pectins.

  7. The structure-anticoagulant activity relationships of sulfated lacquer polysaccharide: effect of carboxyl group and position of sulfation.

    PubMed

    Yang, Jianhong; Du, Yumin; Huang, Ronghua; Wan, Yunyang; Wen, Yan

    2005-07-01

    Regiospecific oxidation of the primary hydroxyl groups in lacquer polysaccharide (LPL, Mw 6.85 x 10(4)) and its NaIO4 oxidation derivatives (LPLde) to C-6 carboxy groups was achieved with NaOCl in the presence of Tempo and NaBr. Sulfate groups were incorporated into the oxidated polysaccharides using Py.SO3 complex as a reagent. Reactivity of polysaccharide hydroxyl group was C-6 > C-2 > C-4. Sulfate groups were mainly linked to the second hydroxy at C-2 in the products. The results of APTT assay showed after incorporation of carboxyl groups into lacquer polysaccharides, the intrinsic coagulation pathway was promoted, and all sulfated polysaccharides had very weak anticoagulant activity within the scope of studied DS (0.39-1.11). These indicated that carboxyl groups and sulfate groups had the synergistic action. At the same time, the anticoagulant activity increased very slowly with the DS in the second hydroxy. This indicated that 6-O-SO3- in the side chains took an important role in the anticoagulant activity.

  8. Complete structure of the cell surface polysaccharide of Streptococcus oralis ATCC 10557: A receptor for lectin-mediated interbacterial adherence

    SciTech Connect

    Abeygunawardana, C.; Bush, C.A. ); Cisar, J.O. )

    1991-07-02

    Lectin-carbohydrate binding is known to play an important role in a number of different cell-cell interactions including those between certain species of oral streptococci and actinomyces that colonize teeth. The cell wall polysaccharides of Streptococcus oralis ATCC 10557, S. oralis 34, and Streptococcus mitis J22, although not identical antigenically, each function as a receptor molecule for the galactose and N-acetylgalactosamine reactive fimbrial lectins of Actinomyces viscosus and Actinomyces naeslundii. Carbohydrate analysis of the receptor polysaccharide isolated from S. oralis ATCC 10557 shows galactose (3 mol), glucose (1 mol), GalNAc (1 mol), and rhamnose (1 mol). {sup 1}H NMR spectra of the polysaccharide show that is partially O-acetylated. Analysis of the {sup 1}H NMR spectrum of the de-O-acetylated polysaccharide shows that it is composed of repeating subunits containing six monosaccharides and that the subunits are joined by a phosphodiester linkage. The {sup 1}H and {sup 13}C NMR spectra were completely assigned by two-dimensional homonuclear correlation methods and by {sup 1}H-detected heteronuclear multiple-quantum correlation ({sup 1}H({sup 13}C)HMQC). The complete {sup 1}H and {sup 13}C assignment of the native polysaccharide was carried out by the same techniques augmented by a {sup 13}C-coupled hybrid HMQC-COSY method, which is shown to be especially useful for carbohydrates in which strong coupling and overlapping peaks in the {sup 1}H spectrum pose difficulties.

  9. In vivo anti-radiation activities of the Ulva pertusa polysaccharides and polysaccharide-iron(III) complex.

    PubMed

    Shi, Jinming; Cheng, Cuilin; Zhao, Haitian; Jing, Jing; Gong, Ning; Lu, Weihong

    2013-09-01

    Polysaccharides with different molecular weights were extracted from Ulva pertusa and fractionated by ultrafiltration. Iron(III) complex of the low molecular-weight U. pertusa polysaccharides were synthesized. Atomic absorption spectrum showed that the iron content of iron(III)-polysaccharide complex was 27.4%. The comparison between U. pertusa polysaccharides and their iron(III) complex showed that iron chelating altered the structural characteristics of the polysaccharides. The bioactivity analysis showed that polysaccharide with low molecular weight was more effective than polysaccharide with high molecular weight in protecting mice from radiation induced damages on bone marrow cells and immune system. Results also proved that the anti-radiation and anti-oxidative activity of iron(III) complex of low molecular-weight polysaccharides were not less than that of low molecular-weight polysaccharides.

  10. Structure of the acidic O-specific polysaccharide from Proteus vulgaris O39 containing 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-non-2-ulosonic acid.

    PubMed

    Kondakova, A N; Perepelov, A V; Bartodziejska, B; Shashkov, A S; Senchenkova, S N; Wykrota, M; Knirel, Y A; Rozalski, A

    2001-07-12

    The O-specific polysaccharide of Proteus vulgaris O39 was found to contain a new acidic component of Proteus lipopolysaccharides, 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-non-2-ulosonic acid (di-N-acetylpseudaminic acid, Pse5Ac7Ac). The following structure of the polysaccharide was determined by NMR spectroscopy, including 2D 1H,(1)H COSY, TOCSY, ROESY, and 1H,(13)C HMQC experiments, along with selective cleavage of the polysaccharide by solvolysis with anhydrous trifluoromethanesulfonic (triflic) acid: -->8)-beta-Psep5Ac7Ac-(2-->3)-alpha-L-FucpNAc-(1-->3)-alpha-D-GlcpNAc-(1--> The structure established is unique among the O-specific polysaccharides, which is in accordance with classification of the strain studied into a separate Proteus serogroup.

  11. Structural characterization and immunomodulatory effects of polysaccharides from Phellinus linteus and Phellinus igniarius on the IL-6/IL-10 cytokine balance of the mouse macrophage cell lines (RAW 264.7).

    PubMed

    Suabjakyong, Papawee; Nishimura, Kazuhiro; Toida, Toshihiko; Van Griensven, Leo J L D

    2015-08-01

    Phellinus linteus and igniarius (L.) Quel. have been used in traditional Asian medicine for over two centuries against a variety of diseases. Polysaccharides from their fruiting bodies show strong immunomodulatory activity. In this study we characterized the structure and composition of polysaccharides from Phellinus linteus and Phellinus igniarius by HPLC, GC-MS and NMR (1-H, 13-C, COSY, NOESY and TOCSY). The polysaccharides from P. linteus and P. igniarius mainly contained glucose with minor proportions of mannose, galactose, xylose, arabinose and rhamnose. Methylation analyses showed that the glycosidic linkages were mostly 1 → 3, 1 → 6 or 1 → 3,6. The two-dimensional COSY, NOESY and TOCSY confirmed that these polysaccharides have a main chain of →3)-β-D-Glcp-(1→ with →6)-β-D-Glcp-(1→ side chain. In vitro assays by RT-PCR and ELISA showed that (1 → 3; 1 → 6)-β-D-polysaccharides from P. linteus and P. igniarius decreased TNF-α in RAW 264.7 cells, suggesting an immuno-suppressive activity. Furthermore, these polysaccharides stimulated a high IL-10 response and induced strong suppression of transcription of IL-6. The results suggest that polysaccharides from P. linteus and P. igniarius could possibly find applications in restoring the IL-6/IL-10 balance, the disturbance of which is thought to be related to chronic inflammatory disease, obesity, diabetes type 2, and to mania and depression.

  12. Advances on Bioactive Polysaccharides from Medicinal Plants.

    PubMed

    Xie, Jian-Hua; Jin, Ming-Liang; Morris, Gordon A; Zha, Xue-Qiang; Chen, Han-Qing; Yi, Yang; Li, Jing-En; Wang, Zhi-Jun; Gao, Jie; Nie, Shao-Ping; Shang, Peng; Xie, Ming-Yong

    2016-07-29

    In recent decades, the polysaccharides from the medicinal plants have attracted a lot of attention due to their significant bioactivities, such as anti-tumor activity, antioxidant activity, anticoagulant activity, antidiabetic activity, radioprotection effect, anti-viral activity, hypolipidemic and immunomodulatory activities, which make them suitable for medicinal applications. Previous studies have also shown that medicinal plant polysaccharides are non-toxic and show no side effects. Based on these encouraging observations, most researches have been focusing on the isolation and identification of polysaccharides, as well as their bioactivities. A large number of bioactive polysaccharides with different structural features and biological effects from medicinal plants have been purified and characterized. This review provides a comprehensive summary of the most recent developments in physiochemical, structural features and biological activities of bioactive polysaccharides from a number of important medicinal plants, such as polysaccharides from Astragalus membranaceus, Dendrobium plants, Bupleurum, Cactus fruits, Acanthopanax senticosus, Angelica sinensis (Oliv.) Diels, Aloe barbadensis Miller, and Dimocarpus longan Lour. Moreover, the paper has also been focused on the applications of bioactive polysaccharides for medicinal applications. Recent studies have provided evidence that polysaccharides from medicinal plants can play a vital role in bioactivities. The contents and data will serve as a useful reference material for further investigation, production, and application of these polysaccharides in functional foods and therapeutic agents.

  13. Is the Capsular Bag Perimeter Round or Elliptical?

    PubMed Central

    Amigó, Alfredo; Bonaque-González, Sergio

    2016-01-01

    Purpose: To report findings that could suggest an elliptical shape of the capsular bag. Methods: Five eyes of three patients with axial length greater than 24 mm underwent phacoemulsification cataract surgery with plate-haptic multifocal toric intraocular lens (IOL) implantation oriented in the vertical meridian. Results: In all cases, correct orientation of the IOLs was verified 30 minutes after surgery. After 24 hours, all eyes demonstrated unwanted rotation of the IOLs ranging from 15 to 45 degrees. The IOLs remained stable in the new position in all cases until adhesion of the capsular bag took place. Conclusion: These observations could suggest that the perimeter of the capsular bag has an elliptical shape. Therefore, the IOL tends to become fixated in a meridian of the capsular bag that best fits the diagonal diameter of the IOL. PMID:27413495

  14. Capsular Plication for Treatment of Iatrogenic Hip Instability

    PubMed Central

    Levy, David M.; Grzybowski, Jeffrey; Salata, Michael J.; Mather, Richard C.; Aoki, Stephen K.; Nho, Shane J.

    2015-01-01

    The most commonly reported reasons for persistent hip pain after hip arthroscopy are residual femoroacetabular impingement, dysplasia and dysplasia variants, or extra-articular impingement. There are some cases in which the underlying osseous pathomorphology has been appropriately treated, and the cause of persistent hip pain can be soft-tissue injuries such as chondrolabral tears or capsular abnormalities. Capsular defects after hip arthroscopy may suggest an alteration of the biomechanical properties of the iliofemoral ligament and lead to iatrogenically induced hip instability. There are a growing number of biomechanical and clinical studies showing the importance of capsular management during hip arthroscopy. We describe the workup, examination under anesthesia, diagnostic arthroscopy, and technique of capsular plication for iatrogenic instability of the hip. PMID:26870636

  15. Immunomodulatory Effects of Serotype B Glucuronoxylomannan from Cryptococcus gattii Correlate with Polysaccharide Diameter▿

    PubMed Central

    Fonseca, Fernanda L.; Nohara, Lilian L.; Cordero, Radames J. B.; Frases, Susana; Casadevall, Arturo; Almeida, Igor C.; Nimrichter, Leonardo; Rodrigues, Marcio L.

    2010-01-01

    Glucuronoxylomannan (GXM), the major capsular component in the Cryptococcus complex, interacts with the immune system in multiple ways, which include the activation of Toll-like receptors (TLRs) and the modulation of nitric oxide (NO) production by phagocytes. In this study, we analyzed several structural parameters of GXM samples from Cryptococcus neoformans (serotypes A and D) and Cryptococcus gattii (serotypes B and C) and correlated them with the production of NO by phagocytes and the activation of TLRs. GXM fractions were differentially recognized by TLR2/TLR1 (TLR2/1) and TLR2/6 heterodimers expressed on TLR-transfected HEK293A cells. Higher NF-κB luciferase reporter activity induced by GXM was observed in cells expressing TLR2/1 than in cells transfected with TLR2/6 constructs. A serotype B GXM from C. gattii was the most effective polysaccharide fraction activating the TLR-mediated response. This serotype B polysaccharide, which was also highly efficient at eliciting the production of NO by macrophages, was similar to the other GXM samples in monosaccharide composition, zeta potential, and electrophoretic mobility. However, immunofluorescence with four different monoclonal antibodies and dynamic light-scattering analysis revealed that the serotype B GXM showed particularities in serological reactivity and had the smallest effective diameter among the GXM samples analyzed in this study. Fractionation of additional serotype B GXMs, followed by exposure of these fractions to macrophages, revealed a correlation between NO production and reduced effective diameters. Our results demonstrate a great functional diversity in GXM samples from different isolates and establish their abilities to differentially activate cellular responses. We propose that serological properties as well as physical chemical parameters, such as the diameter of polysaccharide molecules, may potentially influence the inflammatory response against Cryptococcus spp. and may contribute to the

  16. Phase I clinical trial of O-Acetylated pectin conjugate, a plant polysaccharide based typhoid vaccine

    PubMed Central

    Szu, Shousun C.; Lin, Kimi F-Y; Hunt, Steven; Chu, Chiayung; Thinh, Nguyen Duc

    2014-01-01

    Background Typhoid fever remains an important cause of morbidity and mortality in the developing countries. Vi capsular polysaccharide conjugate vaccine demonstrated safety and efficacy in young children in high endemic regions. A novel typhoid conjugate vaccine based on plant polysaccharide pectin was studied in a phase I trial. Methods Fruit pectin, having the same carbohydrate backbone structure as Vi, was purified from citrus peel and used as the polysaccharide source to prepare a semi-synthetic typhoid conjugate vaccine. Pectin was chemically O-acetylated (OAcPec) to antigenically resemble Vi and conjugated to carrier protein rEPA, a recombinant exoprotein A from Pseudomonas aeruginosa. 25 healthy volunteers, 18–45 years old, were injected once with OAcPec-rEPA. Safety and IgG antibodies reactive with Vi and pectin were analyzed. Results No vaccine associated serious adverse reaction was reported. Six weeks after the injection of OAcPec-rEPA, 64% of the volunteers elicited >4 fold rise of anti-Vi IgG. At 26 weeks the level declined, but the difference between the levels at 6 and 26 weeks are not statistically significant. There is a direct correlation between the level of anti-Vi IgG before and after the injection (R2 = 0.96). The anti-Vi IgG can be absorbed by Vi, but not by pectin. There was no corresponding increase of anti-pectin after the injection, indicating the antibody response to OAcPec-rEPA was specific to Vi. There is no Vi-rEPA data in US adults for comparison of immune responses. The OAcPec-rEPA elicited significantly less IgG anti-Vi in US adults than those by Vi-rEPA in Vietnamese adults. Conclusion The O-acetylated pectin conjugate, a plant based typhoid vaccine, is safe and immunogenic in adult volunteers. PMID:24657719

  17. Rheologically interesting polysaccharides from yeasts

    NASA Technical Reports Server (NTRS)

    Petersen, G. R.; Nelson, G. A.; Cathey, C. A.; Fuller, G. G.

    1989-01-01

    We have examined the relationships between primary, secondary, and tertiary structures of polysaccharides exhibiting the rheological property of friction (drag) reduction in turbulent flows. We found an example of an exopolysaccharide from the yeast Cryptococcus laurentii that possessed high molecular weight but exhibited lower than expected drag reducing activity. Earlier correlations by Hoyt showing that beta 1 --> 3, beta 2 --> 4, and alpha 1 --> 3 linkages in polysaccharides favored drag reduction were expanded to include correlations to secondary structure. The effect of sidechains in a series of gellan gums was shown to be related to sidechain length and position. Disruption of secondary structure in drag reducing polysaccharides reduced drag reducing activity for some but not all exopolysaccharides. The polymer from C. laurentii was shown to be more stable than xanthan gum and other exopolysaccharides under the most vigorous of denaturing conditions. We also showed a direct relationship between extensional viscosity measurements and the drag reducing coefficient for four exopolysaccharides.

  18. Comparing the sugar profiles and primary structures of alkali-extracted water-soluble polysaccharides in cell wall between the yeast and mycelial phases from Tremella fuciformis.

    PubMed

    Zhu, Hanyu; Yuan, Yuan; Liu, Juan; Zheng, Liesheng; Chen, Liguo; Ma, Aimin

    2016-05-01

    To gain insights into dimorphism, cell wall polysaccharides from Tremella fuciformis strains were obtained from alkali-extracted water-soluble fractions PTF-M38 (from the mycelial form), PTF-Y3 and PTF-Y8 (from the yeast form) of T. fuciformis strains were used to gain some insights into dimorphism study. Their chemical properties and structural features were investigated using gel permeation chromatography, gas chromatography, UV and IR spectrophotometry and Congo red binding reactions. The results indicated that the backbones of PTF-M38, PTF-Y3 and PTF-Y8 were configured with α-linkages with average molecular weights of 1.24, 1.08, and 1.19 kDa, respectively. PTF-M38 was mainly composed of xylose, mannose, glucose, and galactose in a ratio of 1:1.47:0.48:0.34, while PTF-Y3 and PTF-Y8 were mainly composed of xylose, mannose and glucose in a ratio of 1:1.65:4.06 and 1:1.21:0.44, respectively. The sugar profiles of PTF-M38, PTF-Y3 and PTF-Y8 were also established for further comparison. These profiles showed that all three polysaccharides contained the same sugars but in different ratios, and the carbon sources (xylose, mannose, glucose, and galactose) affected the sugar ratios within the polysaccharides.

  19. Structural and functional characterization of a putative polysaccharide deacetylase of the human parasite Encephalitozoon cuniculi.

    PubMed

    Urch, Jonathan E; Hurtado-Guerrero, Ramon; Brosson, Damien; Liu, Zhanliang; Eijsink, Vincent G H; Texier, Catherine; van Aalten, Daan M F

    2009-06-01

    The microsporidian Encephalitozoon cuniculi is an intracellular eukaryotic parasite considered to be an emerging opportunistic human pathogen. The infectious stage of this parasite is a unicellular spore that is surrounded by a chitin containing endospore layer and an external proteinaceous exospore. A putative chitin deacetylase (ECU11_0510) localizes to the interface between the plasma membrane and the endospore. Chitin deacetylases are family 4 carbohydrate esterases in the CAZY classification, and several bacterial members of this family are involved in evading lysis by host glycosidases, through partial de-N-acetylation of cell wall peptidoglycan. Similarly, ECU11_0510 could be important for E. cuniculi survival in the host, by protecting the chitin layer from hydrolysis by human chitinases. Here, we describe the biochemical, structural, and glycan binding properties of the protein. Enzymatic analyses showed that the putative deacetylase is unable to deacetylate chitooligosaccharides or crystalline beta-chitin. Furthermore, carbohydrate microarray analysis revealed that the protein bound neither chitooligosaccharides nor any of a wide range of other glycans or chitin. The high resolution crystal structure revealed dramatic rearrangements in the positions of catalytic and substrate binding residues, which explain the loss of deacetylase activity, adding to the unusual structural plasticity observed in other members of this esterase family. Thus, it appears that the ECU11_0510 protein is not a carbohydrate deacetylase and may fulfill an as yet undiscovered role in the E. cuniculi parasite.

  20. Relationship between the Intracellular Integrity and the Morphology of the Capsular Envelope in Attached and Free-Living Marine Bacteria

    PubMed Central

    Heissenberger, A.; Leppard, G. G.; Herndl, G. J.

    1996-01-01

    The integrity of the intracellular structures and the presence and dimension of the capsular envelope were investigated in marine snow-associated and marine free-living bacteria by transmission electron microscopy and special fixation techniques. Three categories depending on the presence of internal structures were differentiated. In marine snow, 51% of the marine snow-associated bacterial community was considered intact, 26% had a partly degraded internal structure, and 23% were empty with only the cell wall remaining. For the free-living bacterial community, 34% were intact cells, 42% exhibited damage, and 24% of the cells were lacking any internal structure. We also investigated the morphology and the extent of the bacterial capsular envelope. More than 95% of all intact marine snow-associated bacteria were surrounded by a capsule while (apprx=)55% of empty marine snow-associated bacteria had no capsule. For free-living bacteria, (apprx=)65% of the intact cells had a capsule while (apprx=)80% of the empty free-living bacteria lacked a capsule. Thus there is a clear trend from intact cells which are commonly surrounded by a capsular envelope to empty bacteria for which only the cell wall is remaining. Since bacterioplankton represent the largest living surface in the ocean, it is concluded that the release of intracellular material from bacteria into the environment as well as the release of extracellular capsular material might fuel the dissolved organic matter pool of the ocean. PMID:16535466

  1. Structure of the O-antigen of Providencia stuartii O20, a new polysaccharide containing 5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-d-galacto-non-2-ulosonic acid.

    PubMed

    Shashkov, Alexander S; Kocharova, Nina A; Zatonsky, George V; Błaszczyk, Aleksandra; Knirel, Yuriy A; Rozalski, Antoni

    2007-02-26

    The O-polysaccharide chain of the lipopolysaccharide (LPS) of Providencia stuartii O20 was found to contain d-glucuronic acid, N-acetyl-d-glucosamine, and a rarely occurring higher sugar 5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-d-galacto-non-2-ulosonic acid (di-N-acetyl-8-epilegionaminic acid, 8eLeg5Ac7Ac). Degradation of the LPS with dilute acetic acid caused depolymerization of the polysaccharide chain by the ketosidic linkage to give a tetrasaccharide corresponding to the repeating unit of the polysaccharide. Based on sugar and methylation analyses of the tetrasaccharide and O-deacylated LPS as well as ESIMS, (1)H and (13)C NMR spectroscopy data, the structure of the O-polysaccharide of P. stuartii O20 was established.

  2. Polysaccharide of an edible truffle Tuber rufum: Structural studies and effects on human lymphocytes.

    PubMed

    Pattanayak, Manabendra; Samanta, Surajit; Maity, Prasenjit; Manna, Dilip K; Sen, Ipsita K; Nandi, Ashis K; Panda, Bibhash C; Chattopadhyay, Sourav; Roy, Somenath; Sahoo, Atish K; Gupta, Nibha; Islam, Syed S

    2017-02-01

    A water-soluble heteroglycan (PS-II) with average molecular weight ∼7.27×10(4)Da, was isolated from the fruiting bodies of an edible truffle mushroom Tuber rufum (Pico) var. by hot water extraction. The structural investigation of PS-II has been carried out using acid hydrolysis, methylation analysis, periodate oxidation, and 1D/2D NMR experiments. It was composed of d-glucose, d-galactose, l-fucose in a molar ratio of nearly 4:3:1 respectively. On the basis of these experiments, the repeating unit of the PS-II was found to contain a backbone of two (1→6)-α-d-galactopyranosyl, one (1→4)-α-d-glucopyranosyl, two (1→6)-β-d-glucopyranosyl, and one (1→4)-β-d-glucopyranosyl residues, out of which (1→4)-α-d-glucopyranosyl residue was branched at O-2 position with terminal α-l-fucopyranosyl residue and at O-6 position with terminal α-d-galactopyranosyl residue. Ameliorative activities of the PS-II was observed at different concentrations (25, 50, 100, 200, 400μg/ml) and it maintained the redox balance as well as reduced the lipid peroxidation to protect the cell damage.

  3. Structural elucidation and immunostimulating property of a novel polysaccharide extracted from an edible mushroom Lentinus fusipes.

    PubMed

    Manna, Dilip K; Maity, Prasenjit; Nandi, Ashis K; Pattanayak, Manabendra; Panda, Bibhash C; Mandal, Amit K; Tripathy, Satyajit; Acharya, Krishnendu; Sahoo, Atish K; Gupta, Nibha; Roy, Somnath; Islam, Syed S

    2017-02-10

    A water soluble heteroglycan (PS-II) with an average molecular weight∼60kDa was isolated from the hot aqueous extract of an edible mushroom Lentinus fusipes. The structural characterization of PS-II was carried out using total acid hydrolysis, methylation analyses, periodate oxidation, Smith degradation and 1D/2D NMR experiments. Total acid hydrolysis indicated the presence of D-galactose and D-glucose in a molar ratio of approximately 1:1. The chemical and NMR analyses revealed that the proposed repeating unit of the PS-II had a backbone chain consisting of three (1→6)-linked α-d-galactopyranosyl residue and two (1→6)-linked β-d-glucopyranosyl residues, one of the β-d-glucopyranosyl residue was branched at O-3 position with a terminal β-d-glucopyranosyl. The PS-II exhibited significant in vitro splenocyte and macrophage activations with optimum dose of 20μg/ml and 80μg/ml respectively. Flow cytometry study revealed the protective role of the PS-II against nicotine stimulated lymphocytes. Moreover, the ROS scavenging property of PS-II was also established using DPPH radical scavenging assay.

  4. Mass Spectrometric Imaging of Wheat (Triticum spp.) and Barley (Hordeum vulgare L.) Cultivars: Distribution of Major Cell Wall Polysaccharides According to Their Main Structural Features.

    PubMed

    Veličković, Dušan; Saulnier, Luc; Lhomme, Margot; Damond, Aurélie; Guillon, Fabienne; Rogniaux, Hélène

    2016-08-17

    Arabinoxylans (AX) and (1→3),(1→4)-β-glucans (BG) are the main components of cereal cell walls and influence many aspects of their end uses. Important variations in the composition and structure of these polysaccharides have been reported among cereals and cultivars of a given species. In this work, the spatial distribution of AX and BG in the endosperm of mature grains was established for nine wheat varieties and eight barley varieties using enzymatically assisted mass spectrometry imaging (MSI). Important structural features of the AX and BG polymers that were previously shown to influence their physicochemical properties were assessed. Differences in the distribution of AX and BG structures were observed, both within the endosperm of a given cultivar and between wheat and barley cultivars. This study provides a unique picture of the structural heterogeneity of AX and BG polysaccharides at the scale of the whole endosperm in a series of wheat and barley cultivars. Thus, it can participate meaningfully in a strategy aiming at understanding the structure-function relationships of these two polymers.

  5. Relevance of Fucose-Rich Extracellular Polysaccharides Produced by Rhizobium sullae Strains Nodulating Hedysarum coronarium L. Legumes

    PubMed Central

    Carpéné, Marie-Anne; Couderc, François; Benguedouar, Ammar

    2013-01-01

    Specific and complex interactions between soil bacteria, known as rhizobia, and their leguminous host plants result in the development of root nodules. This process implies a complex dialogue between the partners. Rhizobia synthesize different classes of polysaccharides: exopolysaccharides (EPS), Kdo-rich capsular polysaccharides, lipopolysaccharides, and cyclic β-(1,2)-glucans. These polymers are actors of a successful symbiosis with legumes. We focus here on studying the EPS produced by Rhizobium sullae bacteria that nodulate Hedysarum coronarium L., largely distributed in Algeria. We describe the influence of the carbon source on the production and on the composition of EPS produced by R. sullae A6 and RHF strains. High-molecular-weight EPS preserve the bacteria from desiccation. The structural characterization of the EPS produced by R. sullae strains has been performed through sugar analysis by gas chromatography-mass spectrometry. The low-molecular-weight EPS of one strain (RHF) has been totally elucidated using nuclear magnetic resonance and quantitative time-of-flight tandem mass spectrometry analyses. An unusual fucose-rich EPS has been characterized. The presence of this deoxy sugar seems to be related to nodulation capacity. PMID:23183977

  6. Relevance of fucose-rich extracellular polysaccharides produced by Rhizobium sullae strains nodulating Hedysarum coronarium l. legumes.

    PubMed

    Gharzouli, Razika; Carpéné, Marie-Anne; Couderc, François; Benguedouar, Ammar; Poinsot, Véréna

    2013-03-01

    Specific and complex interactions between soil bacteria, known as rhizobia, and their leguminous host plants result in the development of root nodules. This process implies a complex dialogue between the partners. Rhizobia synthesize different classes of polysaccharides: exopolysaccharides (EPS), Kdo-rich capsular polysaccharides, lipopolysaccharides, and cyclic β-(1,2)-glucans. These polymers are actors of a successful symbiosis with legumes. We focus here on studying the EPS produced by Rhizobium sullae bacteria that nodulate Hedysarum coronarium L., largely distributed in Algeria. We describe the influence of the carbon source on the production and on the composition of EPS produced by R. sullae A6 and RHF strains. High-molecular-weight EPS preserve the bacteria from desiccation. The structural characterization of the EPS produced by R. sullae strains has been performed through sugar analysis by gas chromatography-mass spectrometry. The low-molecular-weight EPS of one strain (RHF) has been totally elucidated using nuclear magnetic resonance and quantitative time-of-flight tandem mass spectrometry analyses. An unusual fucose-rich EPS has been characterized. The presence of this deoxy sugar seems to be related to nodulation capacity.

  7. Structure and Dynamics of Brachypodium Primary Cell Wall Polysaccharides from Two-Dimensional 13C Solid-State Nuclear Magnetic Resonance Spectroscopy

    SciTech Connect

    Wang, Tuo; Salazar, Andre; Zabotina, Olga A.; Hong, Mei

    2014-04-10

    The polysaccharide structure and dynamics in the primary cell wall of the model grass Brachypodium distachyon are investigated for the first time using solid-state nuclear magnetic resonance (NMR). While both grass and non-grass cell walls contain cellulose as the main structural scaffold, the former contains xylan with arabinose and glucuronic acid substitutions as the main hemicellulose, with a small amount of xyloglucan (XyG) and pectins, while the latter contains XyG as the main hemicellulose and significant amounts of pectins. We labeled the Brachypodium cell wall with 13C to allow two-dimensional (2D) 13C correlation NMR experiments under magic-angle spinning. Well-resolved 2D spectra are obtained in which the 13C signals of cellulose, glucuronoarabinoxylan (GAX), and other matrix polysaccharides can be assigned. The assigned 13C chemical shifts indicate that there are a large number of arabinose and xylose linkages in the wall, and GAX is significantly branched at the developmental stage of 2 weeks. 2D 13C–13C correlation spectra measured with long spin diffusion mixing times indicate that the branched GAX approaches cellulose microfibrils on the nanometer scale, contrary to the conventional model in which only unbranched GAX can bind cellulose. The GAX chains are highly dynamic, with average order parameters of 0.4. Biexponential 13C T1 and 1H T relaxation indicates that there are two dynamically distinct domains in GAX: the more rigid domain may be responsible for cross-linking cellulose microfibrils, while the more mobile domain may fill the interfibrillar space. This dynamic heterogeneity is more pronounced than that of the non-grass hemicellulose, XyG, suggesting that GAX adopts the mixed characteristics of XyG and pectins. Moderate differences in cellulose rigidity are observed between the Brachypodium and Arabidopsis cell walls

  8. Structure and dynamics of Brachypodium primary cell wall polysaccharides from two-dimensional (13)C solid-state nuclear magnetic resonance spectroscopy.

    PubMed

    Wang, Tuo; Salazar, Andre; Zabotina, Olga A; Hong, Mei

    2014-05-06

    The polysaccharide structure and dynamics in the primary cell wall of the model grass Brachypodium distachyon are investigated for the first time using solid-state nuclear magnetic resonance (NMR). While both grass and non-grass cell walls contain cellulose as the main structural scaffold, the former contains xylan with arabinose and glucuronic acid substitutions as the main hemicellulose, with a small amount of xyloglucan (XyG) and pectins, while the latter contains XyG as the main hemicellulose and significant amounts of pectins. We labeled the Brachypodium cell wall with (13)C to allow two-dimensional (2D) (13)C correlation NMR experiments under magic-angle spinning. Well-resolved 2D spectra are obtained in which the (13)C signals of cellulose, glucuronoarabinoxylan (GAX), and other matrix polysaccharides can be assigned. The assigned (13)C chemical shifts indicate that there are a large number of arabinose and xylose linkages in the wall, and GAX is significantly branched at the developmental stage of 2 weeks. 2D (13)C-(13)C correlation spectra measured with long spin diffusion mixing times indicate that the branched GAX approaches cellulose microfibrils on the nanometer scale, contrary to the conventional model in which only unbranched GAX can bind cellulose. The GAX chains are highly dynamic, with average order parameters of ~0.4. Biexponential (13)C T1 and (1)H T1ρ relaxation indicates that there are two dynamically distinct domains in GAX: the more rigid domain may be responsible for cross-linking cellulose microfibrils, while the more mobile domain may fill the interfibrillar space. This dynamic heterogeneity is more pronounced than that of the non-grass hemicellulose, XyG, suggesting that GAX adopts the mixed characteristics of XyG and pectins. Moderate differences in cellulose rigidity are observed between the Brachypodium and Arabidopsis cell walls, suggesting different effects of the matrix polysaccharides on cellulose. These data provide the first

  9. Structural and biochemical changes induced by pulsed electric field treatments on Cabernet Sauvignon grape berry skins: impact on cell wall total tannins and polysaccharides.

    PubMed

    Cholet, Céline; Delsart, Cristèle; Petrel, Mélina; Gontier, Etienne; Grimi, Nabil; L'hyvernay, Annie; Ghidossi, Remy; Vorobiev, Eugène; Mietton-Peuchot, Martine; Gény, Laurence

    2014-04-02

    Pulsed electric field (PEF) treatment is an emerging technology that is arousing increasing interest in vinification processes for its ability to enhance polyphenol extraction performance. The aim of this study was to investigate the effects of PEF treatment on grape skin histocytological structures and on the organization of skin cell wall polysaccharides and tannins, which, until now, have been little investigated. This study relates to the effects of two PEF treatments on harvested Cabernet Sauvignon berries: PEF1 (medium strength (4 kV/cm); short duration (1 ms)) and PEF2 (low intensity (0.7 kV/cm); longer duration (200 ms)). Histocytological observations and the study of levels of polysaccharidic fractions and total amounts of tannins allowed differentiation between the two treatments. Whereas PEF1 had little effect on the polyphenol structure and pectic fraction, PEF2 profoundly modified the organization of skin cell walls. Depending on the PEF parameters, cell wall structure was differently affected, providing variable performance in terms of polyphenol extraction and wine quality.

  10. Characterization and Comparison of the Structural Features, Immune-Modulatory and Anti-Avian Influenza Virus Activities Conferred by Three Algal Sulfated Polysaccharides

    PubMed Central

    Song, Lin; Chen, Xiaolin; Liu, Xiaodong; Zhang, Fubo; Hu, Linfeng; Yue, Yang; Li, Kecheng; Li, Pengcheng

    2015-01-01

    Three marine macroalgae, i.e., Grateloupia filicina, Ulva pertusa and Sargassum qingdaoense, were selected as the deputies of Rhodophyta, Chlorophyta and Ochrophyta for comparative analysis of the molecular structures and biological activities of sulfated polysaccharides (SP). The ratio of water-soluble polysaccharides, the monosaccharide composition and the sulfated contents of three extracted SPs were determined, and their structures were characterized by Fourier transformation infrared spectroscopy. In addition, biological activity analysis showed that all three SPs had immune-modulatory activity both in vitro and in vivo, and SPs from S. qingdaoense had the best effect. Further bioassays showed that three SPs could not only enhance the immunity level stimulated by inactivated avian influenza virus (AIV) in vivo but also significantly inhibited the activity of activated AIV (H9N2 subtype) in vitro. G. filicina SP exhibited the strongest anti-AIV activity. These results revealed the variations in structural features and bioactivities among three SPs and indicated the potential adjuvants for immune-enhancement and anti-AIV. PMID:26729137

  11. Enzymatic Modifications of Polysaccharides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Polysaccharides are often modified chemically in order to improve its properties or to impart specific characteristics. Indeed quite a few commercial products are based on modified polysaccharides. In this talk, I shall describe a new set of modified polysaccharides based on enzymatic reactions. ...

  12. Structure of a new ribitol teichoic acid-like O-polysaccharide of a serologically separate Proteus vulgaris strain, TG 276-1, classified into a new Proteus serogroup O53.

    PubMed

    Arbatsky, Nikolay P; Kondakova, Anna N; Senchenkova, Sof'ya N; Siwińska, Malgorzata; Shashkov, Alexander S; Zych, Krystyna; Knirel, Yuriy A; Sidorczyk, Zygmunt

    2007-10-15

    An unusual ribitol teichoic acid-like O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide from a previously non-classified Proteus vulgaris strain TG 276-1. Structural studies using chemical analyses and 2D (1)H and (13)C NMR spectroscopy showed that the polysaccharide is a zwitterionic polymer with a repeating unit containing 2-acetamido-4-amino-2,4,6-trideoxy-D-galactose (D-FucNAc4N) and two D-ribitol phosphate (D-Rib-ol-5-P) residues and having the following structure:[formula: see text] where the non-glycosylated ribitol residue is randomly mono-O-acetylated. Based on the unique O-polysaccharide structure and the finding that the strain studied is serologically separate among Proteus bacteria, we propose to classify P. vulgaris strain TG 276-1 into a new Proteus serogroup, O53.

  13. Structure of the O-polysaccharide of Proteus vulgaris O44: a new O-antigen that contains an amide of D-glucuronic acid with L-alanine.

    PubMed

    Toukach, Filip V; Perepelov, Andrei V; Bartodziejska, Beata; Shashkov, Alexander S; Blaszczyk, Aleksandra; Arbatsky, Nikolay P; Rozalski, Antoni; Knirel, Yuriy A

    2003-06-23

    The O-polysaccharide of Proteus vulgaris O44, strain PrK 67/57 was studied by 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, ROESY, H-detected 1H, 13C HMQC, HMQC-TOCSY and HMBC experiments. The polysaccharide was found to contain an amide of D-glucuronic acid with L-alanine [D-GlcA6(L-Ala)], and the following structure of the linear pentasaccharide repeating unit was established: [structure: see text]. The structural data of the O-polysaccharide and the results of serological studies with P. vulgaris O44 O-antiserum showed that the strain studied is unique among Proteus bacteria, which is in agreement with its classification in a separate Proteus serogroup, O44.

  14. Chronic Neck Pain: Making the Connection Between Capsular Ligament Laxity and Cervical Instability

    PubMed Central

    Steilen, Danielle; Hauser, Ross; Woldin, Barbara; Sawyer, Sarah

    2014-01-01

    The use of conventional modalities for chronic neck pain remains debatable, primarily because most treatments have had limited success. We conducted a review of the literature published up to December 2013 on the diagnostic and treatment modalities of disorders related to chronic neck pain and concluded that, despite providing temporary relief of symptoms, these treatments do not address the specific problems of healing and are not likely to offer long-term cures. The objectives of this narrative review are to provide an overview of chronic neck pain as it relates to cervical instability, to describe the anatomical features of the cervical spine and the impact of capsular ligament laxity, to discuss the disorders causing chronic neck pain and their current treatments, and lastly, to present prolotherapy as a viable treatment option that heals injured ligaments, restores stability to the spine, and resolves chronic neck pain. The capsular ligaments are the main stabilizing structures of the facet joints in the cervical spine and have been implicated as a major source of chronic neck pain. Chronic neck pain often reflects a state of instability in the cervical spine and is a symptom common to a number of conditions described herein, including disc herniation, cervical spondylosis, whiplash injury and whiplash associated disorder, postconcussion syndrome, vertebrobasilar insufficiency, and Barré-Liéou syndrome. When the capsular ligaments are injured, they become elongated and exhibit laxity, which causes excessive movement of the cervical vertebrae. In the upper cervical spine (C0-C2), this can cause a number of other symptoms including, but not limited to, nerve irritation and vertebrobasilar insufficiency with associated vertigo, tinnitus, dizziness, facial pain, arm pain, and migraine headaches. In the lower cervical spine (C3-C7), this can cause muscle spasms, crepitation, and/or paresthesia in addition to chronic neck pain. In either case, the presence of

  15. Chronic neck pain: making the connection between capsular ligament laxity and cervical instability.

    PubMed

    Steilen, Danielle; Hauser, Ross; Woldin, Barbara; Sawyer, Sarah

    2014-01-01

    The use of conventional modalities for chronic neck pain remains debatable, primarily because most treatments have had limited success. We conducted a review of the literature published up to December 2013 on the diagnostic and treatment modalities of disorders related to chronic neck pain and concluded that, despite providing temporary relief of symptoms, these treatments do not address the specific problems of healing and are not likely to offer long-term cures. The objectives of this narrative review are to provide an overview of chronic neck pain as it relates to cervical instability, to describe the anatomical features of the cervical spine and the impact of capsular ligament laxity, to discuss the disorders causing chronic neck pain and their current treatments, and lastly, to present prolotherapy as a viable treatment option that heals injured ligaments, restores stability to the spine, and resolves chronic neck pain. The capsular ligaments are the main stabilizing structures of the facet joints in the cervical spine and have been implicated as a major source of chronic neck pain. Chronic neck pain often reflects a state of instability in the cervical spine and is a symptom common to a number of conditions described herein, including disc herniation, cervical spondylosis, whiplash injury and whiplash associated disorder, postconcussion syndrome, vertebrobasilar insufficiency, and Barré-Liéou syndrome. When the capsular ligaments are injured, they become elongated and exhibit laxity, which causes excessive movement of the cervical vertebrae. In the upper cervical spine (C0-C2), this can cause a number of other symptoms including, but not limited to, nerve irritation and vertebrobasilar insufficiency with associated vertigo, tinnitus, dizziness, facial pain, arm pain, and migraine headaches. In the lower cervical spine (C3-C7), this can cause muscle spasms, crepitation, and/or paresthesia in addition to chronic neck pain. In either case, the presence of

  16. Evaluation of lipopolysaccharides and polysaccharides of different epitopic structures in the indirect enzyme-linked immunosorbent assay for diagnosis of brucellosis in small ruminants and cattle.

    PubMed

    Alonso-Urmeneta, B; Marín, C; Aragón, V; Blasco, J M; Díaz, R; Moriyón, I

    1998-11-01

    Brucella abortus and Brucella melitensis have surface lipopolysaccharides and polysaccharides carrying B. melitensis-type (M) and B. abortus-type (A) epitopes as well as common (C) epitopes present in all smooth Brucella biotypes. Crude lipopolysaccharides, hydrolytic O polysaccharides, and native hapten polysaccharides of MC or AC specificity were evaluated in indirect enzyme-linked immunosorbent assays with polyclonal, monoclonal, or protein G conjugates by using sera from cattle, sheep, and goats infected with AC, MC, or AMC Brucella biotypes. Regardless of the antigen, the levels of antibodies were lower in goats than in sheep and highest in cattle. The diagnostic performance of the assay was not affected by the absence of lipid A-core epitopes, the presence of contaminating outer membrane proteins, the AC or MC epitopic structure of the absorbed antigen, or the conjugate used. Moreover, with sera from cattle vaccinated with B. abortus S19 (AC) or from sheep and goats vaccinated with B. melitensis Rev 1 (MC), AC and MC antigens showed similar levels of reactivity. The results show that antibodies to the C epitopes largely dominate in infection, and this is consistent with the existence of multiple overlapping C epitopes (V. Weynants, D. Gilson, A. Cloeckaert, A. Tibor, P. A. Denoel, F. Godfroid, J. N. Limet, and J.-J. Letesson, Infect. Immun. 65:1939-1943, 1997) rather than with one or two C epitopes. It is concluded that, by adaptation to the corresponding antibody levels, brucellosis in cattle, sheep, and goats can be diagnosed by immunosorbent assay with a single combination of conjugate and antigen.

  17. Sulfated polysaccharides and immune response: promoter or inhibitor?

    PubMed

    Chen, D; Wu, X Z; Wen, Z Y

    2008-06-01

    Sulfated polysaccharides, which frequently connect to core protein, are expressed not only on cell surface but also throughout the extracellular matrix. Besides providing structural integrity of cells, sulfated polysaccharides interact with a variety of sulfated polysaccharides-binding proteins, such as growth factors, cytokines, chemokines and proteases. Sulfated polysaccharides play two-edged roles, inhibitor and promoter, in immune response. Some sulfated polysaccharides act as the immunosuppressor by blocking inflammatory signal transduction induced by proinflammatory cytokines, suppressing the activation of complement and inhibiting the process that leukocytes adhere to and pass through endothelium. On the contrary, the interaction between immune cells and sulfated polysaccharides produced by bacteria, endothelial cells and immune cells initiate the occurrence of immune response. It promotes the processes of recognizing and arresting antigen, migrating transendothelium, moving into and out of immune organ and enhancing the proliferation of lymphocyte. The structure of sulfated polysaccharides, such as molecular weight and sulfated sites heterogeneity, especially the degree of disaccharide sulfation, position of the sulfate moiety and organization of sulfated domains, may play critical role in their controversial effects. As a consequence, the interaction between sulfated polysaccharides and sulfated polysaccharide-binding proteins may be changed by modifying the structure of sulfated polysaccharides chains. The administration of drug targeting sulfated polysaccharide-protein interaction may be useful in treating inflammatory related diseases.

  18. Polysaccharide-based strategies for heart tissue engineering.

    PubMed

    Silva, Amanda K A; Juenet, Maya; Meddahi-Pellé, Anne; Letourneur, Didier

    2015-02-13

    Polysaccharides are abundant biomolecules in nature presenting important roles in a wide variety of living systems processes. Considering the structural and biological functions of polysaccharides, their properties have raised interest for tissue engineering. Herein, we described the latest advances in cardiac tissue engineering mediated by polysaccharides. We reviewed the data already obtained in vitro and in vivo in this field with several types of polysaccharides. Cardiac injection, intramyocardial in situ polymerization strategies, and scaffold-based approaches involving polysaccharides for heart tissue engineering are thus discussed.

  19. Type-specific capsular antigen is associated with virulence in late-onset group B Streptococcal type III disease.

    PubMed Central

    Klegerman, M E; Boyer, K M; Papierniak, C K; Levine, L; Gotoff, S P

    1984-01-01

    Strain differences have been postulated to explain the observation that group B Streptococcus type III (GBS III) late-onset disease occurs in only a fraction of colonized infants. To determine the distribution of type-specific polysaccharide antigen (Ag) in GBS III, Ag was measured by rocket immunoelectrophoresis in both supernatant fluids and EDTA extracts and by radial immunodiffusion in multiple HCl extracts of the pellet from cultures of 10 strains of GBS III. Capsular Ag was defined as the sum of Ag in EDTA extracts + Ag in multiple HCl extracts. Both Ag in EDTA extracts and Ag in supernatant fluids correlated with capsular Ag (r = 0.94). GBS III strains were obtained from the blood of 19 infants with late-onset sepsis, from the cerebrospinal fluid or blood of 22 infants with late-onset meningitis, and from mucosal surfaces of both 18 infants and 12 mothers of infants with low levels of type-specific antibody and asymptomatic colonization. Mean values of Ag in supernatant fluids in strains from infants with late-onset sepsis (1.50 +/- 0.08 micrograms/ml) and late-onset meningitis (1.67 +/- 0.09 micrograms/ml) were significantly greater than those in asymptomatic colonization strains (1.14 +/- 0.05 micrograms/ml; P less than 0.001). The number of organisms required for a 50% lethal dose in the chick embryo, determined in 29 strains, was inversely related to Ag in supernatant fluids (r = -0.60). The demonstration that the quantity of capsular Ag produced by GBS III strains is related to their virulence in chick embryos and to their invasiveness in susceptible infants supports the hypothesis that Ag is a virulence factor in humans. Images PMID:6423540

  20. Mycoplasma agalactiae Secretion of β-(1→6)-Glucan, a Rare Polysaccharide in Prokaryotes, Is Governed by High-Frequency Phase Variation

    PubMed Central

    Baranowski, E.; Pau-Roblot, C.; Sagné, E.; Citti, C.

    2016-01-01

    ABSTRACT Mycoplasmas are minimal, wall-less bacteria but have retained the ability to secrete complex carbohydrate polymers that constitute a glycocalyx. In members of the Mycoplasma mycoides cluster, which are important ruminant pathogens, the glycocalyx includes both cell-attached and cell-free polysaccharides. This report explores the potential secretion of polysaccharides by M. agalactiae, another ruminant pathogen that belongs to a distant phylogenetic group. Comparative genomic analyses showed that M. agalactiae possesses all the genes required for polysaccharide secretion. Notably, a putative synthase gene (gsmA) was identified, by in silico reconstruction of the biosynthetic pathway, that could be involved in both polymerization and export of the carbohydrate polymers. M. agalactiae polysaccharides were then purified in vitro and found to be mainly cell attached, with a linear β-(1→6)-glucopyranose structure [β-(1→6)-glucan]. Secretion of β-(1→6)-glucan was further shown to rely on the presence of a functional gsmA gene, whose expression is subjected to high-frequency phase variation. This event is governed by the spontaneous intraclonal variation in length of a poly(G) tract located in the gsmA coding sequence and was shown to occur in most of the M. agalactiae clinical isolates tested in this study. M. agalactiae susceptibility to serum-killing activity appeared to be dictated by ON/OFF switching of β-(1→6)-glucan secretion, suggesting a role of this phenomenon in survival of the pathogen when it invades the host bloodstream. Finally, β-(1→6)-glucan secretion was not restricted to M. agalactiae but was detected also in M. mycoides subsp. capri PG3T, another pathogen of small ruminants. IMPORTANCE Many if not all bacteria are able to secrete polysaccharides, either attached to the cell surface or exported unbound into the extracellular environment. Both types of polysaccharides can play a role in bacterium-host interactions. Mycoplasmas are

  1. Why were polysaccharides necessary?

    PubMed

    Tolstoguzov, Vladimir

    2004-12-01

    The main idea of this paper is that the primordial soup may be modelled by food systems whose structure-property relationship is based on non-specific interactions between denatured biopolymers. According to the proposed hypothesis, polysaccharides were the first biopolymers that decreased concentration of salts in the primordial soup, 'compatibilised' and drove the joint evolution of proto-biopolymers. Synthesis of macromolecules within the polysaccharide-rich medium could have resulted in phase separation of the primordial soup and concentration of the polypeptides and nucleic acids in the dispersed phase particles. The concentration of proto-biopolymer mixtures favoured their cross-linking in hybrid supermacromolecules of conjugates. The cross-linking of proto-biopolymers could occur by hydrophobic, electrostatic interactions, H-bonds due to freezing aqueous mixed biopolymer dispersions and/or by covalent bonds due to the Maillard reaction. Cross-linking could have increased the local concentration of chemically different proto-biopolymers, fixed their relative positions and made their interactions reproducible. Attractive-repulsive interactions between cross-linked proto-biopolymer chains could develop pairing of the monomer units, improved chemical stability (against hydrolysis) and led to their mutual catalytic activity and coding. Conjugates could probably evolve to the first self-reproduced entities and then to specialized cellular organelles. Phase separation of the primordial soup with concentration of conjugates in the dispersed particles has probably resulted in proto-cells.

  2. Why Were Polysaccharides Necessary?

    NASA Astrophysics Data System (ADS)

    Tolstoguzov, Vladimir

    2004-12-01

    The main idea of this paper is that the primordial soup may be modelled by food systems whose structure-property relationship is based on non-specific interactions between denatured biopolymers. According to the proposed hypothesis, polysaccharides were the first biopolymers that decreased concentration of salts in the primordial soup, `compatibilised' and drove the joint evolution of proto-biopolymers. Synthesis of macromolecules within the polysaccharide-rich medium could have resulted in phase separation of the primordial soup and concentration of the polypeptides and nucleic acids in the dispersed phase particles. The concentration of proto-biopolymer mixtures favoured their cross-linking in hybrid supermacromolecules of conjugates. The cross-linking of proto-biopolymers could occur by hydrophobic, electrostatic interactions, H-bonds due to freezing aqueous mixed biopolymer dispersions and/or by covalent bonds due to the Maillard reaction. Cross-linking could have increased the local concentration of chemically different proto-biopolymers, fixed their relative positions and made their interactions reproducible. Attractive-repulsive interactions between cross-linked proto-biopolymer chains could develop pairing of the monomer units, improved chemical stability (against hydrolysis) and led to their mutual catalytic activity and coding. Conjugates could probably evolve to the first self-reproduced entities and then to specialized cellular organelles. Phase separation of the primordial soup with concentration of conjugates in the dispersed particles has probably resulted in proto-cells.

  3. Polysaccharides from Extremophilic Microorganisms

    NASA Astrophysics Data System (ADS)

    Nicolaus, B.; Moriello, V. Schiano; Lama, L.; Poli, A.; Gambacorta, A.

    2004-02-01

    Several marine thermophilic strains were analyzed for exopolysaccharide production. The screening process revealed that a significant number of thermophilic microorganisms were able to produce biopolymers, and some of them also revealed interesting chemical compositions. We have identified four new polysaccharides from thermophilic marine bacteria, with complex primary structures and with different repetitive units: a galacto-mannane type from strain number 4004 and mannane type for the other strains. The thermophilic Bacillus thermantarcticus produces two exocellular polysaccharides (EPS 1, EPS 2) that give the colonies a typical mucous character. The exopolysaccharide fraction was produced with all substrates assayed, although a higher yield 400 mg liter-1 was obtained with mannose as carbon and energy source. NMR spectra confirmed that EPS 1 was a heteropolysaccharide of which the repeating unit was constituted by four different α-D-mannoses and three different β-D-glucoses. It seems to be close to some xantan polymers. EPS 2 was a mannan. Four different α-D-mannoses were found as the repeating unit. Production and chemical studies of biopolymers produced by halophilic archaea, Haloarcula species were also reported.

  4. Crystal structures of starch binding domain from Rhizopus oryzae glucoamylase in complex with isomaltooligosaccharide: insights into polysaccharide binding mechanism of CBM21 family.

    PubMed

    Chu, Chen-Hsi; Li, Kun-Mou; Lin, Shih-Wei; Chang, Margaret Dah-Tsyr; Jiang, Ting-Ying; Sun, Yuh-Ju

    2014-06-01

    Glucoamylases are responsible for hydrolysis of starch and polysaccharides to yield β-D-glucose. Rhizopus oryzae glucoamylase (RoGA) is composed of an N-terminal starch binding domain (SBD) and a C-terminal catalytic domain connected by an O-glycosylated linker. Two carbohydrate binding sites in RoSBD have been identified, site I is created by three highly conserved aromatic residues, Trp47, Tyr83, and Tyr94, and site II is built up by Tyr32 and Phe58. Here, the two crystal structures of RoSBD in complex with only α-(1,6)-linked isomaltotriose (RoSBD-isoG3) and isomaltotetraose (RoSBD-isoG4) have been determined at 1.2 and 1.3 Å, respectively. Interestingly, site II binding is observed in both complexes, while site I binding is only found in the RoSBD-isoG4 complex. Hence, site II acts as the recognition binding site for carbohydrate and site I accommodates site II to bind isoG4. Site I participates in sugar binding only when the number of glucosyl units of oligosaccharides is more than three. Taken together, two carbohydrate binding sites in RoSBD cooperate to reinforce binding mode of glucoamylase with polysaccharides as well as the starch.

  5. Layer-by-layer structured polysaccharides-based multilayers on cellulose acetate membrane: Towards better hemocompatibility, antibacterial and antioxidant activities

    NASA Astrophysics Data System (ADS)

    Peng, Lincai; Li, Hui; Meng, Yahong

    2017-04-01

    The development of multifunctional cellulose acetate (CA) membranes with enhanced hemocompatibility and antibacterial and antioxidant activities is extremely important for biomedical applications. In this work, significant improvements in hemocompatibility and antibacterial and antioxidant activities of cellulose acetate (CA) membranes were achieved via layer-by-layer (LBL) deposition of chitosan (CS) and water-soluble heparin-mimicking polysaccharides (i.e., sulfated Cantharellus cibarius polysaccharides, SCP) onto their surface. The surface chemical compositions, growth manner, surface morphologies, and wetting ability of CS/SCP multilayer-modified CA membranes were characterized, respectively. The systematical evaluation of hemocompatibility revealed that CS/SCP multilayer-modified CA membranes significantly improved blood compatibility including resistance to non-specific protein adsorption, suppression of platelet adhesion and activation, prolongation of coagulation times, inhibition of complement activation, as well as reduction in blood hemolysis. Meanwhile, CS/SCP multilayer-modified CA membranes exhibited strong growth inhibition against Escherichia coli and Staphylococcus aureus, as well as high scavenging abilities against superoxide and hydroxyl radicals. In summary, the CS/SCP multilayers could confer CA membranes with integrated hemocompatibility and antibacterial and antioxidant activities, which might have great potential application in the biomedical field.

  6. Structural Characteristics and Antioxidative Capability of the Soluble Polysaccharides Present in Dictyophora indusiata (Vent. Ex Pers.) Fish Phallaceae

    PubMed Central

    Ker, Yaw-Bee; Chen, Kuan-Chou; Peng, Chiung-Chi; Hsieh, Chiu-Lan; Peng, Robert Y.

    2011-01-01

    Dictyophora indusiata (Vent. ex Pers.) Fish Phallaceae (Chinese name Zhu-Sūn, the bamboo fungi) has been used as a medicinal mushroom to treat many inflammatory, gastric and neural diseases since 618 AD in China. We hypothesize that the soluble polysaccharides (SP) present in D. indusiata and their monosaccharide profiles can act as an important role affecting the antioxidative capability, which in turn would influence the biological activity involving anti-inflammatory, immune enhancing and anticancer. We obtained six SP fractions and designated them as D1, a galactoglucan; D2, a galactan; D3, the isoelectrically precipitated riboglucan from 2% NaOH; D4, a myoinositol; D5 and D6, the mannogalactans. The total SP accounted for 37.44% w/w, their molecular weight (MW) ranged within 801–4656 kDa. D3, having the smallest MW 801 kDa, exhibited the most potent scavenging effect against the α,α-diphenyl-β-picrylhydrazyl, •OH−, and •O2− radicals, yielding IC50 values 0.11, 1.02 and 0.64 mg mL−1, respectively. Thus we have confirmed our hypothesis that the bioactivity of D. indusiata is related in majority, if not entirely, to its soluble polysaccharide type regarding the MW and monosaccharide profiles. PMID:21799678

  7. Polysaccharide-producing bacteria isolated from paper machine slime deposits.

    PubMed

    Rättö, M; Suihko, M-L; Siika-aho, M

    2005-03-01

    Development of novel enzymatic methods for slime deposit control in paper mills requires knowledge of polysaccharide-producing organisms and the polysaccharide structures present in deposits. In this work, 27 polysaccharide-producing bacteria were isolated from slime samples collected from different parts of a paper machine. Most of the isolates produced polysaccharides in liquid culture and nine of them were selected for production of polysaccharides for characterisation. The selected isolates belonged to seven different genera: Bacillus, Brevundimonas, Cytophaga, Enterobacter, Klebsiella, Paenibacillus and Starkeya. Using ribotyping, partial 16S rDNA sequencing, physiological tests and fatty acid analysis, four of the nine isolates: Bacillus cereus, Brevundimonas vesicularis, K. pneumoniae and P. stellifer were identified to the species level. Production of polysaccharides by the selected isolates varied between 0.07 and 1.20 g L(-1), the highest amount being produced by B. vesicularis. The polysaccharides were heteropolysaccharides with varying proportions of galactose, glucose mannose, rhamnose fucose and uronic acids.

  8. The structures of core regions from enterobacterial lipopolysaccharides - an update.

    PubMed

    Holst, Otto

    2007-06-01

    To the major virulence factors of Gram-negative bacteria belong the lipopolysaccharides (endotoxins), which are very well characterized for their immunological, pharmacological and pathophysiological effects displayed in eucaryotic cells and organisms. In general, these amphiphilic lipopolysaccharides comprise three regions, which can be differentiated by their structures, function, genetics and biosynthesis: lipid A, the core region and a polysaccharide portion, which may be the O-specific polysaccharide, Enterobacterial Common Antigen (ECA) or a capsular polysaccharide. In the past, much emphasis has been laid on the elucidation of the structure-function relation. The lipid A was proven to represent the toxic principle of endotoxic active lipopolysaccharides, however, its toxicity depends not only on its structure but also on that of the core region, which is covalently linked to lipid A. Thus, and since the core region possesses immunogenic properties, complete structural analyses of lipopolysaccharides core regions and of structure-function relation are highly important for a better understanding of lipopolysaccharides action. To date, quite a number of core structures from lipopolysaccharides of various Gram-negative bacteria have been published and summarized in several overviews. This short review adds to this knowledge those structures of enterobacterial lipopolysaccharides that were published between January 2002 and October 2006.

  9. Structural Characterization and Immunological Activities of a Novel Water-Soluble Polysaccharide from the Fruiting Bodies of Culinary-Medicinal Winter Mushroom, Flammulina velutipes (Agaricomycetes).

    PubMed

    Feng, Ting; Jia, Wei; Wang, Wen-Han; Lin, Chi-Chung; Fan, Hua; Zhang, Jing-Song; Bao, Hai-Ying

    2016-01-01

    A water-soluble polysaccharide, designated FVPA2, was isolated from the fruiting bodies of Flammulina velutipes using DEAE Sepharose Fast Flow and gel-permeation chromatography. Its structure was elucidated by monosaccharide composition and methylation analysis, ultraviolet, Fourier transform infrared spectrometry, and nuclear magnetic resonance spectroscopy. Results showed that FVPA2 was a homogeneous heteropolysaccharide containing galactose, fucose, and mannose in a molar ratio of 5:1:1. High-performance liquid chromatography indicated its molecular weight as 3.4 × 104 Da. FVPA2 also has a repeating unit. In vitro immunomodulatory studies showed that Raw264.7 cells were stimulated to secret nitric oxide upon administration of 200-500 µg/mL FVPA2. FVPA2 also stimulated the proliferation of mouse spleen lymphocytes and B lymphocytes.

  10. A Novel ICOS-Independent, but CD28- and SAP-Dependent, Pathway of T Cell-Dependent, Polysaccharide-Specific Humoral Immunity in Response to Intact Streptococcus pneumoniae versus Pneumococcal Conjugate Vaccine

    DTIC Science & Technology

    2008-01-01

    PPS14) and the phosphorylcholine determinant (PC) of the cell wall C-polysaccharide (C-PS, teichoic acid). The protein- and PS-specific IgG responses...hydroxy-3-nitrophenyl)acetyl; PC, phosphorylcholine determi- nant of teichoic or lipoteichoic acid; Pn, intact Streptococcus pneumoniae; PPS14, capsular

  11. Characterization of size, structure and purity of serogroup X Neisseria meningitidis polysaccharide, and development of an assay for quantification of human antibodies.

    PubMed

    Xie, Ouli; Bolgiano, Barbara; Gao, Fang; Lockyer, Kay; Swann, Carolyn; Jones, Christopher; Delrieu, Isabelle; Njanpop-Lafourcade, Berthe-Marie; Tamekloe, Tsidi Agbeko; Pollard, Andrew J; Norheim, Gunnstein

    2012-08-31

    Serogroup X Neisseria meningitidis (MenX) has recently emerged as a cause of localized disease outbreaks in sub-Saharan Africa. In order to prepare for vaccine development, MenX polysaccharide (MenX PS) was purified by standard methods and analyzed for identity and structure by NMR spectroscopy. This study presents the first full assignment of the structure of the MenX PS using (13)C, (1)H and (31)P NMR spectroscopy and total correlation spectroscopy (TOCSY) and (1)H-(13)C heteronuclear single quantum coherence (HSQC). Molecular size distribution analysis using HPLC-SEC with multi-angle laser light scattering (MALLS) found the single peak of MenX PS to have a weight-average molar mass of 247,000g/mol, slightly higher than a reference preparation of purified serogroup C meningococcal polysaccharide. MenX PS tended to be more thermostable than serogroup A PS. A method for the quantification of MenX PS was developed by use of high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). A novel and specific ELISA assay for quantification of human anti-MenX PS IgG based on covalent linkage of the MenX PS to functionally modified microtitre plates was developed and found valid for the assessment of the specific antibody concentrations produced in response to MenX vaccination or natural infection. The current work thus provides the necessary background for the development of a MenX PS-based vaccine to prevent meningococcal infection caused by bacteria bearing this capsule.

  12. Improved conjugation and purification strategies for the preparation of protein-polysaccharide conjugates.

    PubMed

    Suárez, N; Massaldi, H; Franco Fraguas, L; Ferreira, F

    2008-12-12

    A glycoconjugate constituted by the Streptococcus pneumoniae serotype 14 capsular polysaccharide (CPS14) and bovine serum albumin (BSA) was prepared, and the unique properties of Sephadex LH-20 were used to separate the conjugate from the unconjugated material. The strength of this approach consists in its capacity to produce pure polysaccharide-protein conjugate in good yield and free from unconjugated material, a common residual contaminant of this type of immunobiologicals. The CPS14-BSA conjugate prepared via an improved 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP)-activation technique was characterized chemically and its immunogenicity was evaluated in mice. The purified conjugate, unlike the corresponding polysaccharide, produced a T-cell-dependent response in this species.

  13. α-Amylase-assisted extraction of polysaccharides from Panax ginseng.

    PubMed

    Sun, Lin; Wu, Di; Ning, Xin; Yang, Guang; Lin, Ziheng; Tian, Meihong; Zhou, Yifa

    2015-04-01

    In this paper, α-amylase-assisted extraction was used to isolate the polysaccharide that remained in hot water-extracted ginseng. The yield of the polysaccharide was 9.0%, almost equal to that of the hot water-extracted polysaccharide. Using anion exchange and gel permeation chromatography, the polysaccharide was fractionated into a neutral polysaccharide fraction and six pectic fractions. The neutral fraction accounted for 76% of the polysaccharide and contained both amylopectin and amylose. The pectic polysaccharide fractions were identified to be arabinogalactan, type-I rhamnogalacturonan and homogalacturonan-type pectin by high-performance liquid chromatography, Fourier transform-infrared and nuclear magnetic resonance analysis. Structural and lymphocyte proliferation activity results showed that these polysaccharides were different from those extracted by hot water, indicating that ginseng contains complex polysaccharides with diverse structures, which results in its diverse pharmacological activities. The α-amylase-assisted extraction is a novel method for preparing ginseng polysaccharides and could be applied toward the further study and exploration of ginseng. These findings provide technical and theoretical support for ginseng pharmacology.

  14. Structure of the glycerol phosphate-containing O-polysaccharides and serological studies of the lipopolysaccharides of Proteus mirabilis CCUG 10704 (OE) and Proteus vulgaris TG 103 classified into a new Proteus serogroup, O54.

    PubMed

    Kołodziejska, Katarzyna; Perepelov, Andrei V; Zabłotni, Agnieszka; Drzewiecka, Dominika; Senchenkova, Sof'ya N; Zych, Krystyna; Shashkov, Alexander S; Knirel, Yuriy A; Sidorczyk, Zygmunt

    2006-07-01

    O-Polysaccharides were obtained from the lipopolysaccharides of Proteus mirabilis CCUG 10704 (OE) and Proteus vulgaris TG 103 and studied by chemical analyses and one- and two-dimensional (1)H and (13)C nuclear magnetic resonance spectroscopy, including rotating-frame nuclear Overhauser effect spectroscopy, H-detected (1)H,(13)C heteronuclear single-quantum spectroscopy and (1)H,(31)P heteronuclear multiple-quantum spectroscopy experiments. The Proteus mirabilis OE polysaccharide was found to have a trisaccharide repeating unit with a lateral glycerol phosphate group. The Proteus vulgaris TG 103 produces a similar O-polysaccharide, which differs in incomplete substitution with glycerol phosphate (c. 50% of the stoichiometric amount) and the presence of an O-acetyl group at position 6 of the 2-acetamido-2-deoxygalactose (GalNAc) residue. These structures are unique among the known bacterial polysaccharide structures. Based on the structural and serological data of the lipopolysaccharides, it is proposed to classify both strains studied into a new Proteus serogroup, O54, as two subgroups, O54a,54b and O54a,54c. The serological relatedness of the Proteus O54 and some other Proteus lipopolysaccharides is discussed.

  15. Crystal structure to 2.45 A resolution of a monoclonal Fab specific for the Brucella A cell wall polysaccharide antigen.

    PubMed

    Rose, D R; Przybylska, M; To, R J; Kayden, C S; Oomen, R P; Vorberg, E; Young, N M; Bundle, D R

    1993-07-01

    The atomic structure of an antibody antigen-binding fragment (Fab) at 2.45 A resolution shows that polysaccharide antigen conformation and Fab structure dictated by combinatorial diversity and domain association are responsible for the fine specificity of the Brucella-specific antibody, YsT9.1. It discriminates the Brucella abortus A antigen from the nearly identical Brucella melitensis M antigen by forming a groove-type binding site, lined with tyrosine residues, that accommodates the rodlike A antigen but excludes the kinked structure of the M antigen, as envisioned by a model of the antigen built into the combining site. The variable-heavy (VH) and variable-light (VL) domains are derived from genes closely related to two used in previously solved structures, M603 and R19.9, respectively. These genes combine in YsT9.1 to form an antibody of totally different specificity. Comparison of this X-ray structure with a previously built model of the YsT9.1 combining site based on these homologies highlights the importance of VL:VH association as a determinant of specificity and suggests that small changes at the VL:VH interface, unanticipated in modeling, may cause significant modulation of binding-site properties.

  16. Important determinants for fucoidan bioactivity: a critical review of structure-function relations and extraction methods for fucose-containing sulfated polysaccharides from brown seaweeds.

    PubMed

    Ale, Marcel Tutor; Mikkelsen, Jørn D; Meyer, Anne S

    2011-01-01

    Seaweeds--or marine macroalgae--notably brown seaweeds in the class Phaeophyceae, contain fucoidan. Fucoidan designates a group of certain fucose-containing sulfated polysaccharides (FCSPs) that have a backbone built of (1→3)-linked α-L-fucopyranosyl or of alternating (1→3)- and (1→4)-linked α-L-fucopyranosyl residues, but also include sulfated galactofucans with backbones built of (1→6)-β-D-galacto- and/or (1→2)-β-D-mannopyranosyl units with fucose or fuco-oligosaccharide branching, and/or glucuronic acid, xylose or glucose substitutions. These FCSPs offer several potentially beneficial bioactive functions for humans. The bioactive properties may vary depending on the source of seaweed, the compositional and structural traits, the content (charge density), distribution, and bonding of the sulfate substitutions, and the purity of the FCSP product. The preservation of the structural integrity of the FCSP molecules essentially depends on the extraction methodology which has a crucial, but partly overlooked, significance for obtaining the relevant structural features required for specific biological activities and for elucidating structure-function relations. The aim of this review is to provide information on the most recent developments in the chemistry of fucoidan/FCSPs emphasizing the significance of different extraction techniques for the structural composition and biological activity with particular focus on sulfate groups.

  17. Monoclonal antibodies against plant cell wall polysaccharides

    SciTech Connect

    Hahn, M.G.; Bucheli, E.; Darvill, A.; Albersheim, P. )

    1989-04-01

    Monoclonal antibodies (McAbs) are useful tools to probe the structure of plant cell wall polysaccharides and to localize these polysaccharides in plant cells and tissues. Murine McAbs were generated against the pectic polysaccharide, rhamnogalacturonan I (RG-I), isolated from suspension-cultured sycamore cells. The McAbs that were obtained were grouped into three classes based upon their reactivities with a variety of plant polysaccharides and membrane glycoproteins. Eleven McAbs (Class I) recognize epitope(s) that appear to be immunodominant and are found in RG-I from sycamore and maize, citrus pectin, polygalacturonic acid, and membrane glycoproteins from suspension-cultured cells of sycamore, maize, tobacco, parsley, and soybean. A second group of five McAbs (Class II) recognize epitope(s) present in sycamore RG-I, but do not bind to any of the other polysaccharides or glycoproteins recognized by Class I. Lastly, one McAb (Class III) reacts with sycamore RG-I, sycamore and tamarind xyloglucan, and sycamore and rice glucuronoarabinoxylan, but does not bind to maize RG-I, polygalacturonic acid or the plant membrane glycoproteins recognized by Class I. McAbs in Classes II and III are likely to be useful in studies of the structure, biosynthesis and localization of plant cell wall polysaccharides.

  18. Glycaemic and insulinaemic responses to feeding hay with different non-structural carbohydrate content in control and polysaccharide storage myopathy-affected horses.

    PubMed

    Borgia, L; Valberg, S; McCue, M; Watts, K; Pagan, J

    2011-12-01

    The aim of this study was to determine whether the glycaemic/insulinaemic responses to hay with non-structural carbohydrate (NSC, soluble carbohydrate) of 17% (HC), 10% (MC) or 4% (LC) differs in control horses and whether these responses differ between control and horses with polysaccharide storage myopathy (PSSM). Five clinically normal control horses and seven PSSM horses, all unfit and of Quarter Horse breeding (age 9.4 ± 3.4 years, body condition score range: 4.5-6). A crossover design compared the HC and LC hay, with horses randomly assigned to hay type for 5 days, and all horses fed the MC hay during washout, after which the diets were switched. Horses were fed 1.5% BW (as fed) divided into 2 feeding per day, no grain. On morning of the fifth day of each block (seventh day for washout), horses were given 0.5% BW in hay, blood was drawn before and every 30 min for 5 h after feeding, and the rate of intake was measured. Whole blood glucose and plasma insulin were measured. The intake rate was significantly higher for HC. In control horses, the insulin area under the curve (6891.7 ± 3524.2 HC vs. 1185.4 ± 530.2 LC) was significantly higher than LC. Polysaccharide storage myopathy horses had significantly higher glycaemic and insulinaemic responses to HC vs. LC, however; the magnitude of insulin response was lower and glucose response higher in PSSM vs. control horses. Results suggest that insulin responses can differ significantly with the NSC content of hay. Feeding hay with 17% NSC produces elevations in insulin that could be detrimental for PSSM horses.

  19. Structures and serospecificity of threonine-containing O polysaccharides of two clinical isolates belonging to the genus Proteus and their classification into O11 subserogroups.

    PubMed

    Drzewiecka, Dominika; Arbatsky, Nikolay P; Kondakova, Anna N; Shashkov, Alexander S; Knirel, Yuriy A

    2016-11-01

    Two clinical isolates from Polish patients, Proteus mirabilis 9B-m and Proteus genomospecies 3J-r, were found to be serologically related to P mirabilis O11. However, serological studies involving ELISA and Western blotting methods, using lipopolysaccharides (LPSs) extracted from the strains as antigens and native or adsorbed rabbit polyclonal O antisera, specific to the studied strains, revealed slight differences in the cross-reactivity and specificity of the two studied Proteus isolates, when compared to P. mirabilis O11. Two different O polysaccharides containing N-(d-galacturonoyl)-l-threonine were isolated from the LPSs of the isolates. Their structures were determined by chemical analysis and NMR spectroscopy and found to be related to the P. mirabilis O11 antigen structure established earlier, the 9B-m structure differing in the absence of the lateral glucose residue and the 3J-r structure in non-stoichiometric O-acetylation of the threonine residue only. Thus, the Proteus O11 serogroup should be divided into two subgroups: O11a, represented by the 9B-m isolate and O11a, b possessing the additional b epitope, containing the lateral residue of glucose and formed by the 3J-r isolate as well as P. mirabilis 25/57 belonging to O11 serogroup so far. O11a is the sixth new serotype found in Proteus spp. strains recently isolated from patients in central Poland.

  20. Purification and structural characterization of an α-glucosidase inhibitory polysaccharide from apricot (Armeniaca sibirica L. Lam.) pulp.

    PubMed

    Cui, Jie; Gu, Xin; Wang, Fengjun; Ouyang, Jie; Wang, Jianzhong

    2015-05-05

    In this study, the crude polysaccharide (APPS) from the fruiting bodies of apricot (Armeniaca sibirica L. Lam.) was isolated and fractionated by ultrafiltration and Sephadex G-75 gel chromatography. The hypoglycemic activities of all fractions were determined by α-glucosidase inhibitory activity in vitro. The fraction APPS1-2 showed the best activity with an IC50 of 6.06 mg/mL. The properties and chemical compositions of this fraction were analyzed with high-performance liquid chromatography, gel permeation chromatography-eighteen angle laser light scattering instrument, UV spectroscopy, infrared spectroscopy, and NMR spectroscopy ((1)H). The results demonstrated that APPS1-2 was a neutral glycoconjugate with a molecular weight of 25.93 kDa. It comprised rhamnose, glucose, mannose, and galactose, with a relative molar ratio of 1.34:2.01:0.48:0.35. The backbone of APPS1-2 may consist of rhamnose and glucose, but its branches may consist of mannose and galactose. The IR and UV spectrum of APPS1-2 revealed the typical characteristics of heteropolysaccharide. (1)H NMR spectrum showed that APPS1-2 contained α-configurations.

  1. A Simple Technique for Capsular Repair After Hip Arthroscopy

    PubMed Central

    Camp, Christopher L.; Reardon, Patrick J.; Levy, Bruce A.; Krych, Aaron J.

    2015-01-01

    Capsulotomy is typically performed during arthroscopic treatment for femoroacetabular impingement. As the frequency of hip arthroscopy continues to expand rapidly, increased attention is being paid to the implications of interportal capsulotomy and the need for repair. To minimize the risk of postoperative instability, capsular closure has been recommended to restore the anatomy and biomechanical function of the capsule. We present a reliable, efficient, and effective method for arthroscopic closure of the interportal capsulotomy after hip arthroscopy. PMID:26870655

  2. Structural and electronic snapshots during the transition from a Cu(II) to Cu(I) metal center of a lytic polysaccharide monooxygenase by X-ray photoreduction.

    PubMed

    Gudmundsson, Mikael; Kim, Seonah; Wu, Miao; Ishida, Takuya; Momeni, Majid Hadadd; Vaaje-Kolstad, Gustav; Lundberg, Daniel; Royant, Antoine; Ståhlberg, Jerry; Eijsink, Vincent G H; Beckham, Gregg T; Sandgren, Mats

    2014-07-04

    Lytic polysaccharide monooxygenases (LPMOs) are a recently discovered class of enzymes that employ a copper-mediated, oxidative mechanism to cleave glycosidic bonds. The LPMO catalytic mechanism likely requires that molecular oxygen first binds to Cu(I), but the oxidation state in many reported LPMO structures is ambiguous, and the changes in the LPMO active site required to accommodate both oxidation states of copper have not been fully elucidated. Here, a diffraction data collection strategy minimizing the deposited x-ray dose was used to solve the crystal structure of a chitin-specific LPMO from Enterococcus faecalis (EfaCBM33A) in the Cu(II)-bound form. Subsequently, the crystalline protein was photoreduced in the x-ray beam, which revealed structural changes associated with the conversion from the initial Cu(II)-oxidized form with two coordinated water molecules, which adopts a trigonal bipyramidal geometry, to a reduced Cu(I) form in a T-shaped geometry with no coordinated water molecules. A comprehensive survey of Cu(II) and Cu(I) structures in the Cambridge Structural Database unambiguously shows that the geometries observed in the least and most reduced structures reflect binding of Cu(II) and Cu(I), respectively. Quantum mechanical calculations of the oxidized and reduced active sites reveal little change in the electronic structure of the active site measured by the active site partial charges. Together with a previous theoretical investigation of a fungal LPMO, this suggests significant functional plasticity in LPMO active sites. Overall, this study provides molecular snapshots along the reduction process to activate the LPMO catalytic machinery and provides a general method for solving LPMO structures in both copper oxidation states.

  3. Effect of sulfated modification on the molecular characteristics and biological activities of polysaccharides from Hypsizigus marmoreus.

    PubMed

    Bao, HongHui; Choi, Won-Seok; You, SangGuan

    2010-01-01

    The effect of sulfated modification on polysaccharides from Hypsizigus marmoreus was examined by determining their molecular structures and bioactivities. The sulfation, which was implemented by using an orthogonal array design, produced polysaccharides with varying degrees of substitution (DS) ranging from 0.11 to 1.06. The sulfated polysaccharides exhibited a lower average molecular weight (M(w)) and considerably higher radius of gyration (R(g)) than those of native polysaccharide, suggesting that the conformation of the sulfated polysaccharides had been changed towards a more extended type. The inhibitory activity toward cancer cell growth was enhanced by treating with the sulfated polysaccharides by up to 34%, as compared to the native polysaccharide. In addition, treating with the sulfated polysaccharides increased the nitric oxide (NO) and cytokine (IL-1beta and TNF-alpha) release to levels comparable to those detected in the positive control, lipopolysaccharide (LPS), suggesting that the sulfated polysaccharides might have strong immunomodulatory activity.

  4. Structural Characterization of a Novel Polysaccharide from Lepidium meyenii (Maca) and Analysis of Its Regulatory Function in Macrophage Polarization in Vitro.

    PubMed

    Zhang, Mengmeng; Wu, Wenjia; Ren, Yao; Li, Xiaofeng; Tang, Yuqian; Min, Tian; Lai, Furao; Wu, Hui

    2017-02-15

    In our previous study, three novel polysaccharides, named MC-1, MC-2, and MC-3, were separated from the roots of maca (Lepidium meyenii), which is a food source from the Andes region. The structural information and immunomodulatory activity of MC-1 were then investigated. The structure and activity of MC-2 are still unknown. In this study, structural characterization revealed that MC-2 has an average molecular weight of 9.83 kDa and is composed of arabinose (20.9%), mannose (4.5%), glucose (71.9%), and galactose (2.7%). The main linkage types of MC-2 were proven to be (1→5)-α-l-Ara, (1→3)-α-l-Man, (1→)-α-d-Glc, (1→4)-α-d-Glc, (1→6)-α-d-Glc, and (1→6)-β-d-Gal by methylation and NMR analyses. Congo red assay showed that MC-2 possesses a triple-helix conformation. Immunostimulating assays indicated that MC-2 could induce M1 polarization of original macrophages and convert M2 macrophages into M1 phenotype. Although MC-2 could not shift M1 macrophages into M2, it could still inhibit inflammatory reactions induced by lipopolysaccharide. Furthermore, Toll-like receptor 2, tTll-like receptor 4, complement receptor 3, and mannose receptor were confirmed as the membrane receptors for MC-2 on macrophages. These results indicate that MC-2 could potentially be used toward hypoimmunity and tumor therapies.

  5. Structure of the O-specific polysaccharide of Proteus vulgaris O15 containing a novel regioisomer of N-acetylmuramic acid, 2-acetamido-4-O-[(R)-1-carboxyethyl]-2-deoxy-D-glucose.

    PubMed

    Perepelov, Andrei V; Torzewska, Agnieszka; Shashkov, Alexander S; Ziolkowski, Andrzej; Senchenkova, Sof'ya N; Rozalski, Antoni; Knirel, Yuriy A

    2002-11-29

    An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Proteus vulgaris O15 and studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, ROESY, and H-detected 1H,(13)C HMQC experiments. The polysaccharide was found to contain an ether of GlcNAc with lactic acid, and the following structure of the repeating unit was established:-->3)-alpha-D-GlcpNAc4(R-Lac)6Ac-(1-->2)-beta-D-GlcpA-(1-->3)-alpha-L-6dTalp2Ac-(1-->3)-beta-D-GlcpNAc-(1-->where L-6dTal and D-GlcNAc4(R-Lac) are 6-deoxy-L-talose and 2-acetamido-4-O-[(R)-1-carboxyethyl]-2-deoxy-D-glucose, respectively. The latter sugar, which to our knowledge has not been hitherto found in nature, was isolated from the polysaccharide by solvolysis with anhydrous triflic acid and identified by comparison with the authentic synthetic compound. Serological studies with the Smith-degraded polysaccharide showed an importance of 2-substituted GlcA for manifesting of the immunospecificity of P. vulgaris O15.

  6. Structure of the O-polysaccharide of Providencia stuartii O4 containing 4-(N-acetyl-L-aspart-4-yl)amino-4,6-dideoxy-D-glucose.

    PubMed

    Kocharova, Nina A; Torzewska, Agnieszka; Zatonsky, George V; Błaszczyk, Aleksandra; Bystrova, Olga V; Shashkov, Alexander S; Knirel, Yuriy A; Rozalski, Antoni

    2004-01-22

    The O-polysaccharide of Providencia stuartii O4 was obtained by mild acid degradation of the lipopolysaccharide, and the following structure of the pentasaccharide repeating unit was established: [structure: see text] where D-Qui4N(L-AspAc) is 4-(N-acetyl-L-aspart-4-yl)amino-4,6-dideoxy-D-glucose, which has not been hitherto found in bacterial polysaccharides. Structural studies were performed using sugar and methylation analyses, Smith degradation and NMR spectroscopy, including conventional 2D 1H,1H COSY, TOCSY, NOESY and 1H,13C HSQC experiments as well as COSY and NOESY experiments run in an H(2)O-D(2)O mixture to reveal correlations for NH protons.

  7. Outcomes of Capsular Dissection Technique with Use of Bipolar Electrocautery in Total Thyroidectomy: A Rural Tertiary Center Experience

    PubMed Central

    Prakash, S.B.; Priyadarshini, V.

    2016-01-01

    Introduction Total thyroidectomy is one of the most routinely performed head and neck surgical procedures with extremely low mortality. This procedure has been associated with two major complications such as recurrent laryngeal nerve injury and hypocalcaemia due to parathyroid insufficiency. The use of bipolar electrocautery has not been widely accepted in view of thermal damage to adjacent structures. Aim To study the outcomes and complications of capsular dissection technique along with use of bipolar electrocautery in total thyroidectomy. Materials and Methods The study was conducted from May 2013 to May 2016. The study was performed at Department of ENT Otorhinolayngology, DM WIMS Hospital, Wayanad, Kerala, India. This retrospective descriptive study analysed the outcome of 130 patients who underwent total thyroidectomy by capsular dissection technique along with use of bipolar electrocautery for cauterization of vascular pedicles, at our institution over a 3 year period. Results The incidence of permanent unilateral vocal cord palsy was 1.5% and permanent hypocalcaemia was 2.3%. There was no case of haemorrhage or haematoma in this study. Conclusion Total thyroidectomy by capsular dissection technique along with the use of bipolar electrocautery has very low incidence of recurrent laryngeal nerve and parathyroid injury, as per our data. Hence, we recommend this technique along with routine use of bipolar electrocautery for total thyroidectomy. PMID:28208891

  8. Finite-element model of interaction between fungal polysaccharide and monoclonal antibody in the capsule of Cryptococcus neoformans

    PubMed Central

    Rakesh, Vineet; Schweitzer, Andrew D.; Zaragoza, Oscar; Bryan, Ruth; Wong, Kevin; Datta, Ashim; Casadevall, Arturo; Dadachova, Ekaterina

    2008-01-01

    Many microorganisms such as bacteria and fungi possess so-called capsules made of polysaccharides which protect these microorganisms from environmental insults and host immune defenses. The polysaccharide capsule of C. neoformans, a human pathogenic yeast, is capable of self assembly, composed mostly of glucuronoxylomannan (GXM), a polysaccharide with molecular weight of approximately 2,000,000 Da and has several layers with different densities. The objective of this study was to model pore-hindered diffusion and binding of the GXM-specific antibody within the C. neoformans capsule. Using the finite element method (FEM), we created a model which represents the in vivo binding of GXM-specific antibody to a C. neoformans cell taking into account the intravenous infusion time of antibody, antibody diffusion through capsular pores, and Michaelis-Menten kinetics of antibody binding to capsular GXM. The model predicted rapid diffusion of antibody to all regions of the capsule where pore size was greater than the Stokes diameter of the antibody. Binding occurred primarily at intermediate regions of the capsule. The GXM concentration in each capsular region was the principal determinant of the steady-state antibody-GXM complex concentration, while the forward binding rate constant influenced the rate of complex formation in each region. The concentration profiles predicted by the model closely matched experimental immunofluorescence data. Inclusion of different antibody isotypes (IgG, IgA and IgM) into the modeling algorithm resulted in similar complex formation in outer capsular regions, but different depth of binding at inner regions. These results have implications for the development of new antibody-based therapies. PMID:18588334

  9. Fucoidans — sulfated polysaccharides of brown algae

    NASA Astrophysics Data System (ADS)

    Usov, Anatolii I.; Bilan, M. I.

    2009-08-01

    The methods of isolation of fucoidans and determination of their chemical structures are reviewed. The fucoidans represent sulfated polysaccharides of brown algae, the composition of which varies from simple fucan sulfates to complex heteropolysaccharides. The currently known structures of such biopolymers are presented. A variety of the biological activities of fucoidans is briefly summarised.

  10. Antipneumococcal effects of C-reactive protein and monoclonal antibodies to pneumococcal cell wall and capsular antigens.

    PubMed Central

    Briles, D E; Forman, C; Horowitz, J C; Volanakis, J E; Benjamin, W H; McDaniel, L S; Eldridge, J; Brooks, J

    1989-01-01

    Antibodies to pneumococcal capsular polysaccharides are well known for their ability to protect against pneumococcal infection. Recent studies indicate that antibodies to cell wall antigens, including pneumococcal surface protein A and the phosphocholine (PC) determinant of teichoic acids as well as human C-reactive protein (which also binds to PC), can protect mice against pneumococcal infection. In the present study we compared the protective effects of these agents as measured by mouse protection, the blood bactericidal assay, and clearance of pneumococci from the blood and peritoneal cavity. Our findings extend previous results indicating that human C-reactive protein and antibodies to noncapsular antigens are generally less protective than anticapsular antibodies. The new results obtained indicate the following: (i) mouse protection studies with intraperitoneal and intravenous infections provide very similar results; (ii) monoclonal immunoglobulin G2a (IgG2a) antibodies to PC, like IgG1, IgG2b, and IgG3 antibodies to PC, are highly protective against pneumococcal infection in mice; (iii) human antibody to PC is able to protect against pneumococcal infection in mice; (iv) antibodies to PspA are effective at mediating blood and peritoneal clearance of pneumococci; (v) complement is required for the in vivo protective effects of both IgG and IgM antibodies to PC; (vi) IgG1, IgG2b, and IgG3 anti-PC antibodies all mediate complement-dependent lysis of PC-conjugated erythrocytes; and (vii) antibodies and human C-reactive proteins that are reactive with capsular antigens but not cell wall antigens are able to mediate significant antibacterial activity in the blood bactericidal assay. PMID:2707854

  11. Neisseria lactamica and Neisseria meningitidis share lipooligosaccharide epitopes but lack common capsular and class 1, 2, and 3 protein epitopes.

    PubMed

    Kim, J J; Mandrell, R E; Griffiss, J M

    1989-02-01

    Neisseria lactamica, a common human pharyngeal commensal, contributes to acquired immunity to Neisseria meningitidis. To define the surface antigens shared between these two species, we used monoclonal antibodies (MAbs) to study 35 N. lactamica strains isolated in various parts of the world for cross-reactivity with meningococcal capsules, outer membrane proteins, and lipooligosaccharides (LOS). No N. lactamica strain reacted significantly with MAbs specific for capsular group A, B, C, Y, or W, and we were unable to extract capsular polysaccharide from them. Only 2 of 33 strains reacted weakly with MAbs against class 2 serotype proteins P2b and P2c. None reacted with MAbs specific for meningococcal class 1 protein P1.2 or P1.16 or class 2/3 serotype protein P2a or P15. Most N. lactamica strains (30 of 35) bound one or more of seven LOS-specific MAbs. Two LOS epitopes, defined by MAbs O6B4 and 3F11, that are commonly found on pathogenic Neisseria species were found on 25 of 35 N. lactamica. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting showed that the LOS of N. lactamica are composed of multiple components that are physically and antigenically similar to the LOS of pathogenic Neisseria species. Among four other commensal neisserial species, only Neisseria cinerea shared LOS epitopes defined by MAbs O6B4 and 3F11. Previous studies have shown that pharyngeal colonization with N. lactamica induces bactericidal antibodies against the meningococcus. We postulate that shared N. lactamica and meningococcal LOS epitopes may play an important role in the development of natural immunity to the meningococcus.

  12. Water-soluble polysaccharide isolated with alkali from the stem of Physalis alkekengi L.: structural characterization and immunologic enhancement in DNA vaccine.

    PubMed

    Yang, Jingjing; Yang, Fan; Yang, Huimin; Wang, Guiyun

    2015-05-05

    A water-soluble polysaccharide (WSPA) was isolated with alkali and purified from the mature stem of Physalis alkekengi L. WSPA (Mw=31kDa) was an acid heteropolysaccharide, which consisted of Rha, Ara, Xyl, Gal, Glc and GalA in ratio of 1.0:2.5:0.8:2.7:4.4:1.4. The results from structural analysis indicated backbone and branches of WSPA were composed of (1→3)-linked Glc, (1→3)-linked Gal, (1→2)-linked Xyl, (1→2)-linked Ara, and (1→2)-linked Rha residues. However, GalA was distributed only in the backbone of WSPA. All branches of WSPA were at O-2 of (1→6)-linked Gal and terminated with Glc. More importantly, it was found that WSPA significantly enhanced specific antibody IgG response with higher titers of IgG1 as well as IgG2b (p<0.05) in mice immunized with DNA vaccine. Therefore, WSPA can be considered as a potential adjuvant candidate in DNA vaccine.

  13. Bacterial Extracellular Polysaccharides in Biofilm Formation and Function

    PubMed Central

    Limoli, Dominique H.; Jones, Christopher J.; Wozniak, Daniel J.

    2015-01-01

    Microbes produce a biofilm matrix consisting of proteins, extracellular DNA, and polysaccharides that is integral in the formation of bacterial communities. Historical studies of polysaccharides revealed that their overproduction often alters the colony morphology and can be diagnostic in identifying certain species. The polysaccharide component of the matrix can provide many diverse benefits to the cells in the biofilm, including adhesion, protection, and structure. Aggregative polysaccharides act as molecular glue, allowing the bacterial cells to adhere to each other as well as surfaces. Adhesion facilitates the colonization of both biotic and abiotic surfaces by allowing the bacteria to resist physical stresses imposed by fluid movement that could separate the cells from a nutrient source. Polysaccharides can also provide protection from a wide range of stresses, such as desiccation, immune effectors, and predators such as phagocytic cells and amoebae. Finally, polysaccharides can provide structure to biofilms, allowing stratification of the bacterial community and establishing gradients of nutrients and waste products. This can be advantageous for the bacteria by establishing a heterogeneous population that is prepared to endure stresses created by the rapidly changing environments that many bacteria encounter. The diverse range of polysaccharide structures, properties, and roles highlight the importance of this matrix constituent to the successful adaptation of bacteria to nearly every niche. Here, we present an overview of the current knowledge regarding the diversity and benefits that polysaccharide production provides to bacterial communities within biofilms. PMID:26185074

  14. Staphylococcus aureus capsular types and antibody response to lung infection in patients with cystic fibrosis.

    PubMed Central

    Albus, A; Fournier, J M; Wolz, C; Boutonnier, A; Ranke, M; Høiby, N; Hochkeppel, H; Döring, G

    1988-01-01

    Chronic respiratory tract infections caused by Staphylococcus aureus are common in patients with cystic fibrosis (CF). Recently, it was shown in a few CF patients that S. aureus isolates produce capsular polysaccharides (CPs). However, it is not known whether this is a common feature and whether an immune response to CPs in CF is detectable. Therefore, we examined 170 S. aureus isolates from CF patients and healthy individuals for production of CP types 5 and 8 by using monoclonal antibodies. We found that CP-producing staphylococcal isolates were randomly distributed among CF patients and healthy carriers. Eighty-five percent of all isolates produced CPs, 77% of which were type 8. Examination of one sputum sample by an immunofluorescence technique suggested that production of CPs is not an in vitro phenomenon. S. aureus isolates from various sites of a single person often yielded more than one CP type. A random distribution of S. aureus strains with CP type 5 or 8 from the skin and respiratory tracts of patients and from the skin of healthy individuals was found. Antibody response to CP types 5 and 8, measured by enzyme-linked immunosorbent assay, was not elevated in CF patients with chronic S. aureus lung infection in comparison with healthy carriers. On the contrary, in CF patients the ratios of antibodies to CP 8 were significantly lower (P less than 0.005; alpha = 0.025). The ratios of antibodies to CP types did not change when monitored longitudinally over several months. This study suggests that the production of CPs is a universal property of S. aureus and that infected CF patients do not have elevated ratios of antibodies to these antigens. Images PMID:3230130

  15. Interleukin-1-like activity in capsular material from Haemophilus actinomycetemcomitans.

    PubMed Central

    Harvey, W; Kamin, S; Meghji, S; Wilson, M

    1987-01-01

    This paper describes the activity of a bacterial surface component (capsular material, CM) in biological assays for interleukin-1 (IL-1). CM from the periodontal pathogen Haemophilus actinomycetemcomitans was tested in the following in vitro assays: mouse thymocyte proliferation (LAF assay), stimulation of collagenase and prostaglandin (PG) E2 synthesis by articular chondrocytes, and stimulation of PGE2 synthesis by fibroblasts. In all these assays, CM gave a response similar to an IL-1 preparation. This ability to mimic IL-1 suggests an important role for CM in both cell-mediated immunity and connective tissue destruction in localized juvenile periodontitis (LJP). PMID:3032779

  16. Immunomodulatory dietary polysaccharides: a systematic review of the literature

    PubMed Central

    2010-01-01

    Background A large body of literature suggests that certain polysaccharides affect immune system function. Much of this literature, however, consists of in vitro studies or studies in which polysaccharides were injected. Their immunologic effects following oral administration is less clear. The purpose of this systematic review was to consolidate and evaluate the available data regarding the specific immunologic effects of dietary polysaccharides. Methods Studies were identified by conducting PubMed and Google Scholar electronic searches and through reviews of polysaccharide article bibliographies. Only articles published in English were included in this review. Two researchers reviewed data on study design, control, sample size, results, and nature of outcome measures. Subsequent searches were conducted to gather information about polysaccharide safety, structure and composition, and disposition. Results We found 62 publications reporting statistically significant effects of orally ingested glucans, pectins, heteroglycans, glucomannans, fucoidans, galactomannans, arabinogalactans and mixed polysaccharide products in rodents. Fifteen controlled human studies reported that oral glucans, arabinogalactans, heteroglycans, and fucoidans exerted significant effects. Although some studies investigated anti-inflammatory effects, most studies investigated the ability of oral polysaccharides to stimulate the immune system. These studies, as well as safety and toxicity studies, suggest that these polysaccharide products appear to be largely well-tolerated. Conclusions Taken as a whole, the oral polysaccharide literature is highly heterogenous and is not sufficient to support broad product structure/function generalizations. Numerous dietary polysaccharides, particularly glucans, appear to elicit diverse immunomodulatory effects in numerous animal tissues, including the blood, GI tract and spleen. Glucan extracts from the Trametes versicolor mushroom improved survival and

  17. Characterisation of cell wall polysaccharides from rapeseed (Brassica napus) meal.

    PubMed

    Pustjens, Annemieke M; Schols, Henk A; Kabel, Mirjam A; Gruppen, Harry

    2013-11-06

    To enable structural characteristics of individual cell wall polysaccharides from rapeseed (Brassica napus) meal (RSM) to be studied, polysaccharide fractions were sequentially extracted. Fractions were analysed for their carbohydrate (linkage) composition and polysaccharide structures were also studied by enzymatic fingerprinting. The RSM fractions analysed contained pectic polysaccharides: homogalacturonan in which 60% of the galacturonic acid residues are methyl-esterified, arabinan branched at the O-2 position and arabinogalactan mainly type II. This differs from characteristics previously reported for Brassica campestris meal, another rapeseed cultivar. Also, in the alkali extracts hemicelluloses were analysed as xyloglucan both of the XXGG- and XXXG-type decorated with galactosyl, fucosyl and arabinosyl residues, and as xylan with O-methyl-uronic acid attached. The final residue after extraction still contained xyloglucan and remaining (pectic) polysaccharides next to cellulose, showing that the cell wall matrix of RSM is very strongly interconnected.

  18. Structure of the O-polysaccharide and serological cross-reactivity of the Providencia stuartii O33 lipopolysaccharide containing 4-(N-acetyl-D-aspart-4-yl)amino-4,6-dideoxy-D-glucose.

    PubMed

    Torzewska, Agnieszka; Kocharova, Nina A; Zatonsky, George V; Blaszczyk, Aleksandra; Bystrova, Olga V; Shashkov, Alexander S; Knirel, Yuriy A; Rozalski, Antoni

    2004-06-01

    The O-polysaccharide of Providencia stuartii O33 was obtained by mild acid degradation of the lipopolysaccharide and the following structure of the tetrasaccharide repeating unit was established: -->6)-alpha-D-GlcpNAc-(1-->4)-alpha-D-GalpA-(1-->3)-alpha-D-GlcpNAc-(1-->3)-beta-D-Quip4N(Ac-D-Asp)-(1-->, where d-Qui4N(Ac-D-Asp) is 4-(N-acetyl-D-aspart-4-yl)amino-4,6-dideoxy-D-glucose. Structural studies were performed using sugar and methylation analyses and NMR spectroscopy, including conventional 2D 1H, 1H COSY, TOCSY, NOESY and 1H, 13C HSQC experiments as well as COSY and NOESY experiments in an H2O-D2O mixture to reveal correlations for NH protons. The O-polysaccharide of P. stuartii O33 shares an alpha-D-GlcpNAc-(1-->3)-beta-D-Quip4N(Ac-D-Asp) epitope with that of Proteus mirabilis O38, which seems to be responsible for a marked serological cross-reactivity of anti-P. stuartii O33 serum with the lipopolysaccharide of the latter bacterium. P. stuartii O33 is serologically related also to P. stuartii O4, whose O-polysaccharide contains a lateral beta-D-Qui4N(Ac-L-Asp) residue.

  19. Structure of the alanopine-containing O-polysaccharide and serological cross-reactivity of the lipopolysaccharide of Proteus vulgaris HSC 438 classified into a new Proteus serogroup, O76.

    PubMed

    Siwinska, Malgorzata; Shashkov, Alexander S; Kondakova, Anna N; Drzewiecka, Dominika; Zablotni, Agnieszka; Arbatsky, Nikolay P; Valueva, Olga A; Zych, Krystyna; Sidorczyk, Zygmunt; Knirel, Yuriy A

    2013-06-01

    The O-polysaccharide was isolated by mild acid hydrolysis of the lipopolysaccharide of Proteus vulgaris HSC 438, and the following structure was established by chemical methods and one- and two-dimensional (1)H and (13)C NMR spectroscopy: →3)-β-d-Quip4NAlo-(1→3)-α-d-Galp6Ac-(1→6)-α-d-Glcp-(1→3)-α-l-FucpNAc-(1→3)-β-d-GlcpNAc-(1→, where d-Qui4N stands for 4-amino-4,6-dideoxy-d-glucose and Alo for N-((S)-1-carboxyethyl)-l-alanine (alanopine); only about half of the Gal residues are O-acetylated. This structure is unique among the Proteus O-polysaccharides, and therefore it is proposed to classify P. vulgaris HSC 438 into a new Proteus serogroup, O76. A serological cross-reactivity of HSC 438 O-antiserum and lipopolysaccharides of some other Proteus serogroups was observed and accounted for by shared epitopes on the O-polysaccharides or lipopolysaccharide core regions, including that associated with d-Qui4NAlo.

  20. Prevalence, capsular type and antimicrobial susceptibility of Streptococcus suis isolated from slaughter pigs in Korea.

    PubMed Central

    Han, D U; Choi, C; Ham, H J; Jung, J H; Cho, W S; Kim, J; Higgins, R; Chae, C

    2001-01-01

    This study was undertaken to determine the prevalence, capsular serotype, and antimicrobial susceptibility of Streptococcus suis isolated from slaughter pigs. Capsular serotype and antimicrobial susceptibility were determined by coagglutination test and agar dilution minimum inhibitory concentration, respectively. Streptococcus suis was isolated from 55 of the 406 palatine tonsillar samples tested (13.8%) and 14 of the 29 sampled herds (48.3%). Of the 55 isolates recovered from slaughter pigs, 26 (47.3%) were untypeable. Of the remaining 29 isolates, capsular serotypes 9 (9 isolates) and 16 (4 isolates) were the most common, followed by capsular serotypes 4 (3 isolates) and 7 (3 isolates). Every capsulated isolate was typeable and no palatine tonsillar sample yielded more than one serotype. Most of isolates were susceptible to low concentrations (MIC90) of amoxicillin (2 microg/mL), ceftiofur (1 microg/mL), and penicillin (1 microg/mL). No correlation was found between antimicrobial susceptibility and capsular serotype. PMID:11480519

  1. Somatic antigens of Pseudomonas aeruginosa. The structure of O-specific polysaccharide chains of lipopolysaccharides of P. aeruginosa O3 (Lányi), O25 (Wokatsch) and Fisher immunotypes 3 and 7.

    PubMed

    Knirel, Y A; Paramonov, N A; Vinogradov, E V; Shashkov, A S; Dmitriev, B A; Kochetkov, N K; Kholodkova, E V; Stanislavsky, E S

    1987-09-15

    O-specific polysaccharides, obtained on mild acid degradation of lipopolysacchrides of the serologically related strains Pseudomonas aeruginosa O3 (Lányi classification), O25 (Wokatsch classification) and immunotypes 3 and 7 (Fisher classification), are built up of trisaccharide repeating units involving 2-acetamido-2,6-dideoxy-D-galactose (N-acetyl-D-fucosamine), 2,3-diacetamido-2,3-dideoxy-D-mannuronic acid or 2,3-diacetamido-2,3-dideoxy-L-guluronic acid and 3-acetamidino-2-acetamido-2,3-dideoxy-D-mannuronic acid or 3-acetamidino-2-acetamido-2,3-dideoxy-L-guluronic acid. Lányi O3(a),3d,3f and Wokatsch O25 polysaccharides contain also O-acetyl groups. On the basis of solvolysis with anhydrous hydrogen fluoride, resulting in trisaccharide fragments with N-acetylfucosamine residue at the reducing terminus, chemical modifications of the acetamidino group (alkaline hydrolysis to the acetamido group or reductive deamination to the ethylamino group), as well as analysis by 1H-NMR (including nuclear Overhauser effect experiments) and 13C-NMR spectroscopy, and fast-atom bombardment mass spectrometry, it was concluded that the repeating units of the polysaccharides have the following structures: (Formula: see text) where HexNAcAmA = alpha-L-GulNAcAmA (approximately 70%) or beta-D-ManNacAMA (approximately 30%). Lányi O3(a),3d,3f polysaccharide involves two types of repeating units, which differ from each other only in the configuration at C-5 of the 3-acetamidino-2-acetamido-2,3-dideoxyuronic acid residue. Lányi O3(a),3c,O3a,3d,3e and Fisher immunotypes 3 and 7 polysaccharides contain, together with the major repeating units shown above, a small proportion of units in which the derivative of alpha-L-guluronic acid is replaced by the corresponding beta-D-manno isomer. The data obtained provide the opportunity to substantiate the serological interrelations between these strains of P. aeruginosa by the presence in the O-specific polysaccharides of common monosaccharides or

  2. [Saccharide mapping and its application in quality control of polysaccharides from Chinese medicines].

    PubMed

    Li, Shao-ping; Wu, Ding-tao; Zhao, Jing

    2015-09-01

    Polysaccharides with multiple biological activities are usually considered as one of the major bioactive compounds in Chinese medicines (CMs). At present, the development of drug and functional foods related to polysaccharides have attracted a great deal of attention due to their great potential effects and diverse action mechanisms. However, quality control of polysaccharides is the bottleneck and a challenge due to their complexity and chemical diversity. Actually, the bioactivities of polysaccharides are closely related to their molecular structures. In order to ensure their safety and efficacy, the development of novel approaches based on the molecular structures for the improvement of quality control of polysaccharides is significantly important. Therefore, in this article, the relationship between biological activities and chemical structures, as well as the action mechanisms of polysaccharides from CMs were summarized first. Furthermore, saccharide mapping, a novel strategy for quality control of bioactive polysaccharides from CMs, was introduced and the application and perspectives were also discussed.

  3. Structural, serological, and genetic characterization of the O-antigen of Providencia alcalifaciens O40.

    PubMed

    Ovchinnikova, Olga G; Liu, Bin; Guo, Dan; Kocharova, Nina A; Bialczak-Kokot, Magdalena; Shashkov, Alexander S; Feng, Lu; Rozalski, Antoni; Wang, Lei; Knirel, Yuriy A

    2012-12-01

    The O-polysaccharide chain of the lipopolysaccharide (O-antigen) on the bacterial cell surface is one of the most structurally variable cell components and serves as a basis for serotyping of Gram-negative bacteria, including human opportunistic pathogens of the genus Providencia. In this work, the O-antigen of Providencia alcalifaciens O40 was obtained by mild acid degradation of the isolated lipopolysaccharide and studied by chemical methods and high-resolution NMR spectroscopy. The following structure of the O-polysaccharide was established: →4)-β-D-Quip3NFo-(1→3)-α-D-Galp-(1→3)-β-D-GlcpA-(1→3)-β-D-GalpNAc-(1→, where GlcA stands for glucuronic acid and Qui3NFo for 3,6-dideoxy-3-formamidoglucose. The O40-antigen was found to be structurally and serologically related to the O-antigens of P. alcalifaciens O5 and Providencia stuartii O18. The O40-antigen gene cluster between cpxA and yibK was sequenced, and the gene functions were predicted in silico. In agreement with the O-polysaccharide structure established, the genes for the synthesis of dTDP-D-Qui3NFo, UDP-D-Gal, UDP-D-GlcA, and UDP-D-GalNAc as well as those encoding three glycosyltransferases, flippase (Wzx), and O-antigen polymerase (Wzy) were recognized. In addition, homologues of wza, wzb, and wzc genes, which are required for the surface expression of capsular polysaccharides, were found within the gene cluster, suggesting that the O-polysaccharide studied is a part of the capsule-related form of the lipopolysaccharide called K(LPS).

  4. Depolymerization of sulfated polysaccharides under hydrothermal conditions.

    PubMed

    Morimoto, Minoru; Takatori, Masaki; Hayashi, Tetsuya; Mori, Daiki; Takashima, Osamu; Yoshida, Shinichi; Sato, Kimihiko; Kawamoto, Hitoshi; Tamura, Jun-ichi; Izawa, Hironori; Ifuku, Shinsuke; Saimoto, Hiroyuki

    2014-01-30

    Fucoidan and chondroitin sulfate, which are well known sulfated polysaccharides, were depolymerized under hydrothermal conditions (120-180°C, 5-60min) as a method for the preparation of sulfated polysaccharides with controlled molecular weights. Fucoidan was easily depolymerized, and the change of the molecular weight values depended on the reaction temperature and time. The degree of sulfation and IR spectra of the depolymerized fucoidan did not change compared with those of untreated fucoidan at reaction temperatures below 140°C. However, fucoidan was partially degraded during depolymerization above 160°C. Nearly the same depolymerization was observed for chondroitin sulfate. These results indicate that hydrothermal treatment is applicable for the depolymerization of sulfated polysaccharides, and that low molecular weight products without desulfation and deformation of the initial glycan structures can be obtained under mild hydrothermal conditions.

  5. SUPPRESSION OF BLOOD GROUP AGGLUTINABILITY OF HUMAN ERYTHROCYTES BY CERTAIN BACTERIAL POLYSACCHARIDES

    PubMed Central

    Ceppellini, Ruggero; Landy, Maurice

    1963-01-01

    Erythrocytes coated with bacterial capsular polysaccharides, notably the Vi antigen, were no longer agglutinated by antibodies directed against the various antigens native to the red cell surface. These effects could not be attributed to prevention of antibody uptake even though in some systems the uptake of antibody was diminished. In fact, agglutination by Rh-incomplete antibody was brought back to the original titer only after the sensitized Vi-coated cells had been subjected to ten alternating exposures to globulin and antiglobulin. Hemagglutination by Newcastle, mumps, and influenza viruses was also suppressed. Erythrocytes coated with Vi polysaccharide assumed the distinctive physicochemical attributes of this acidic polymer which results in a stabilization of the erythrocyte suspension as manifested by increased electrophoretic mobility and a striking decrease in the rate of sedimentation. Among the possible models for explaining the nature of the Vi effect on immune agglutination, the data favor interference with lattice formation. PMID:14019651

  6. Structures and gene clusters of the O-specific polysaccharides of the lipopolysaccharides of Escherichia coli O69 and O146 containing glycolactilic acids: ether conjugates of D-GlcNAc and D-Glc with (R)- and (S)-lactic acid.

    PubMed

    Knirel, Yuriy A; Guo, Xi; Senchenkova, Sof'ya N; Perepelov, Andrei V; Liu, Bin; Shashkov, Alexander S

    2017-02-01

    Based on the O-specific polysaccharides of the lipopolysaccharides (O-polysaccharides, O-antigens), strains of a clonal species Escherichia coli are classified into 184 O serogroups. In this work, structures of the O-polysaccharides of E. coli O69 and O146 were elucidated and gene clusters for their biosynthesis were characterized. The O-polysaccharides were released from the lipopolysaccharides by mild acid hydrolysis and studied by sugar analysis and one- and two-dimensional (1)H and (13)C NMR spectroscopy before and after O-deacetylation. The O146 polysaccharide was also studied by Smith degradation. The O69 and O146 polysaccharides were found to contain ether conjugates of monosaccharides with lactic acid called glycolactilic acids: 2-acetamido-2-deoxy-4-O-[(R)-1-carboxyethyl]-D-glucose (D-GlcNAc4Rlac) and 3-O-[(S)-1-carboxyethyl]-D-glucose (D-Glc3Slac), respectively. Structures of the pentasaccharide repeats of the O-polysaccharides were established, and that of E. coli O69 was found to differ in the presence of D-GlcNAc4Rlac from the structure reported for this bacterium earlier (Erbing C, Kenne L, Lindberg B. 1977. Carbohydr Res. 56:371-376). The O-antigen gene clusters of E. coli O69 and O146 between conserved genes galF and gnd were analyzed taking into account the O-polysaccharide structures established, and functions of putative genes for synthesis of D-Glc3Slac and D-GlcNAc4Rlac and for glycosyltransferases were assigned based on homology with O-antigen biosynthesis genes of other enteric bacteria. It was found that in E. coli and Shigella spp. predicted enolpyruvate reductases of the biosynthesis pathway of glycolactilic acids, LarR and LarS, which catalyze formation of conjugates with (R)- or (S)-lactic acid, respectively, are distinguished by sequence homology and size.

  7. The structure of the O-polysaccharide from the lipopolysaccharide of Providencia stuartii O57 containing an amide of D-galacturonic acid with L-alanine.

    PubMed

    Kocharova, Nina A; Ovchinnikova, Olga G; Bushmarinov, Ivan S; Toukach, Filip V; Torzewska, Agnieszka; Shashkov, Alexander S; Knirel, Yuriy A; Rozalski, Antoni

    2005-03-21

    The O-polysaccharide (O-antigen) was obtained by mild acid degradation of the lipopolysaccharide of Providencia stuartii O57:H29. Studies by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including two-dimensional (1)H,(1)H COSY, TOCSY, ROESY, H-detected (1)H,(13)C HSQC, and HMBC experiments, showed that the polysaccharide contains an amide of D-galacturonic acid with L-alanine and has the following pentasaccharide repeating unit: [formula: see text

  8. Polysaccharides from Agaricus bisporus and Agaricus brasiliensis show similarities in their structures and their immunomodulatory effects on human monocytic THP-1 cells

    PubMed Central

    2011-01-01

    Background Mushroom polysaccharides have traditionally been used for the prevention and treatment of a multitude of disorders like infectious illnesses, cancers and various autoimmune diseases. Crude mushroom extracts have been tested without detailed chemical analyses of its polysaccharide content. For the present study we decided to chemically determine the carbohydrate composition of semi-purified extracts from 2 closely related and well known basidiomycete species, i.e. Agaricus bisporus and A. brasiliensis and to study their effects on the innate immune system, in particular on the in vitro induction of pro-inflammatory cytokines, using THP-1 cells. Methods Mushroom polysaccharide extracts were prepared by hot water extraction and precipitation with ethanol. Their composition was analyzed by GC-MS and NMR spectroscopy. PMA activated THP-1 cells were treated with the extracts under different conditions and the production of pro-inflammatory cytokines was evaluated by qPCR. Results Semi-purified polysaccharide extracts of A. bisporus and A. brasiliensis (= blazei) were found to contain (1→6),(1→4)-linked α-glucan, (1→6)-linked β-glucan, and mannogalactan. Their proportions were determined by integration of 1H-NMR signs, and were considerably different for the two species. A. brasiliensis showed a higher content of β-glucan, while A. bisporus presented mannogalactan as its main polysaccharide. The extracts induced a comparable increase of transcription of the pro-inflammatory cytokine genes IL-1β and TNF-α as well as of COX-2 in PMA differentiated THP-1 cells. Pro-inflammatory effects of bacterial LPS in this assay could be reduced significantly by the simultaneous addition of A. brasiliensis extract. Conclusions The polysaccharide preparations from the closely related species A. bisporus and A. brasiliensis show major differences in composition: A. bisporus shows high mannogalactan content whereas A. brasiliensis has mostly β-glucan. Semi

  9. Chemical composition and molecular structure of polysaccharide-protein biopolymer from Durio zibethinus seed: extraction and purification process

    PubMed Central

    2012-01-01

    Background The biological functions of natural biopolymers from plant sources depend on their chemical composition and molecular structure. In addition, the extraction and further processing conditions significantly influence the chemical and molecular structure of the plant biopolymer. The main objective of the present study was to characterize the chemical and molecular structure of a natural biopolymer from Durio zibethinus seed. A size-exclusion chromatography coupled to multi angle laser light-scattering (SEC-MALS) was applied to analyze the molecular weight (Mw), number average molecular weight (Mn), and polydispersity index (Mw/Mn). Results The most abundant monosaccharide in the carbohydrate composition of durian seed gum were galactose (48.6-59.9%), glucose (37.1-45.1%), arabinose (0.58-3.41%), and xylose (0.3-3.21%). The predominant fatty acid of the lipid fraction from the durian seed gum were palmitic acid (C16:0), palmitoleic acid (C16:1), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2), and linolenic acid (C18:2). The most abundant amino acids of durian seed gum were: leucine (30.9-37.3%), lysine (6.04-8.36%), aspartic acid (6.10-7.19%), glycine (6.07-7.42%), alanine (5.24-6.14%), glutamic acid (5.57-7.09%), valine (4.5-5.50%), proline (3.87-4.81%), serine (4.39-5.18%), threonine (3.44-6.50%), isoleucine (3.30-4.07%), and phenylalanine (3.11-9.04%). Conclusion The presence of essential amino acids in the chemical structure of durian seed gum reinforces its nutritional value. PMID:23062269

  10. The TLR2 agonist in polysaccharide-K is a structurally distinct lipid which acts synergistically with the protein-bound β-glucan.

    PubMed

    Quayle, Kenneth; Coy, Catherine; Standish, Leanna; Lu, Hailing

    2015-04-01

    Protein-bound polysaccharide-K (Krestin; PSK) is a hot-water extract of Trametes versicolor with immune stimulatory activity. It has been used for the past 30 years and has demonstrated anti-tumor efficacy in multiple types of cancer. The ability of PSK to activate dendritic cells and T cells is dependent on its ability to stimulate Toll-like receptor 2 (TLR2), yet it remains unknown which structural component within PSK activates TLR2. The purpose of this study was to identify the TLR2 agonist within PSK and understand its role in the overall mechanism of PSK's immunogenic activity. TLR2 activity was eliminated by treatment with lipoprotein lipase but not by trypsin or lyticase. Rapid centrifugation of PSK can separate the fraction with TLR2 agonist activity from the soluble β-glucan fraction. To study the potential interaction between the β-glucan component and the lipid component, we labeled the soluble β-glucan with fluorescein. Uptake of the labeled β-glucan by J774A macrophages and JAWSII dendritic cells was inhibited by anti-Dectin-1 antibody but not by anti-TLR2 antibody, confirming that Dectin-1 is the receptor for β-glucan. Interestingly, pre-treatment of JAWSII cells with the TLR2-active lipid fraction significantly enhanced the uptake of the soluble β-glucan, indicating the synergy between the TLR2 agonist component and the β-glucan component. Altogether, these results present evidence that PSK has two active components-the well-characterized protein-bound β-glucan and a previously unreported lipid-which work synergistically via the Dectin-1 and TLR2 receptors.

  11. The effect of the polysaccharide composition and structure of dietary fibers on cecal fermentation and fecal excretion.

    PubMed

    Eastwood, M A; Brydon, W G; Anderson, D M

    1986-07-01

    The fermentation of dietary fibers gives a clue to their mode of action. Wheat bran and gum tragacanth increase stool weight but have no effect on serum cholesterol or on hydrogen excretion. Gum arabic and pectin in the form of raw carrot have no effect on stool weight but decrease serum cholesterol and are associated with an increase in breath-hydrogen excretion. Other fiber sources like gum karaya have no effect on stool weight, serum cholesterol, or breath hydrogen. There are no correlations between the chemical composition and structure of the fibers studied and their physiological effects.

  12. Antiobesity properties of mushroom polysaccharides – A Review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mushrooms are widely consumed for their nutritional and health benefits. To stimulate broader interest in the reported health-promoting properties of bioactive mushroom polysaccharides, this presentation will survey the chemistry (isolation and structural characterization) and reported antiobesity ...

  13. Synbiotic matrices derived from plant oligosaccharides and polysaccharides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A porous synbiotic matrix was prepared by lyophilization of alginate and pectin or fructan oligosaccharides and polysaccharides cross-linked with calcium. These synbiotic matrices were excellent physical structures to support the growth of Lactobacillus acidophilus (1426) and Lactobacillus reuteri (...

  14. Nonencapsulated Variant of Cryptococcus neoformans I. Virulence Studies and Characterization of Soluble Polysaccharide

    PubMed Central

    Kozel, Thomas R.; Cazin, John

    1971-01-01

    A weakly virulent nonencapsulated variant of Cryptococcus neoformans is described. The chemical structure and antigenicity of the soluble polysaccharides produced by the variant strain and a typical virulent strain were compared. The soluble polysaccharides produced by both strains were composed of the same constituent monosaccharides; however, the virulent strain produced a polysaccharide having a greater uronic acid content and a larger molecular size than that of the variant strain. Soluble polysaccharides from the two strains are not closely related immunologically. Soluble polysaccharide obtained from the virulent strain did not affect persistence of the variant strain in mice. PMID:16557967

  15. The polysaccharide and low molecular weight components of Opuntia ficus indica cladodes: Structure and skin repairing properties.

    PubMed

    Di Lorenzo, Flaviana; Silipo, Alba; Molinaro, Antonio; Parrilli, Michelangelo; Schiraldi, Chiara; D'Agostino, Antonella; Izzo, Elisabetta; Rizza, Luisa; Bonina, Andrea; Bonina, Francesco; Lanzetta, Rosa

    2017-02-10

    The Opuntia ficus-indica multiple properties are reflected in the increasing interest of chemists in the identification of its natural components having pharmaceutical and/or cosmetical applications. Here we report the structural elucidation of Opuntia ficus-indica mucilage that highlighted the presence of components differing for their chemical nature and the molecular weight distribution. The high molecular weight components were identified as a linear galactan polymer and a highly branched xyloarabinan. The low molecular weight components were identified as lactic acid, D-mannitol, piscidic, eucomic and 2-hydroxy-4-(4'-hydroxyphenyl)-butanoic acids. A wound healing assay was performed in order to test the cicatrizing properties of the various components, highlighting the ability of these latter to fasten dermal regeneration using a simplified in vitro cellular model based on a scratched keratinocytes monolayer. The results showed that the whole Opuntia mucilage and the low molecular weight components are active in the wound repair.

  16. Extraction optimization, isolation, preliminary structural characterization and antioxidant activities of the cell wall polysaccharides in the petioles and pedicels of Chinese herbal medicine Qian (Euryale ferox Salisb.).

    PubMed

    Wu, Chengying; Wang, Xinsheng; Wang, Hong; Shen, Bei; He, Xiaoxiao; Gu, Wei; Wu, Qinan

    2014-03-01

    Cell wall polysaccharides in the petioles and pedicels of Qian (Euryale ferox Salisb.) (EFPP) were extracted using ultrasound-assisted technique. Response surface methodology (RSM) based on Box-Behnken design (BBD) was employed to optimize extraction parameters for the maximum purity of polysaccharides. The results showed that the optimum extraction conditions were extraction temperature of 80 °C, extraction time of 32 min, ultrasonic power of 270W and liquid-to-solid ratio of 40 mL/g. Under the optimal conditions, the experimental purity of polysaccharides was 62.57% ± 1.68%, which was very close to the predicted. The crude EFPP were isolated using DEAE-52 column and four major fractions (EFPP-1, EFPP-2, EFPP-3 and EFPP-4) were obtained. Typical functional groups of polysaccharides were characteristic for EFPP-1, EFPP-3 and EFPP-4 from FT-IR spectrum. Furthermore, the crude EFPP and three fractions (EFPP-1, EFPP-3 and EFPP-4) possessed appreciable in vitro antioxidant effects on α,α-diphenyl-β-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), hydroxyl radical scavenging and reducing powers. Then, the crude EFPP and EFPP-4 could effective against H2O2-induced injury on HUVEC and VSMC through enhancement of T-AOC, SOD and CAT activities and decrease of MDA content.

  17. Incorporation of bacterial extracellular polysaccharide by black fly larvae (Simuliidae)

    USGS Publications Warehouse

    Couch, C.A.; Meyer, J.L.; Hall, R.O.

    1996-01-01

    Black fly larvae (Simulium) assimilated, with high efficiency (80-90%), bacterial extracellular polysaccharide (EPS) extracted from laboratory cultures of a pseudomonad isolated from the Ogeechee River. Incorporation was traced using 13C-labelled EPS offered to larvae as a coating on a mixture of 1-??m latex beads and kaolin particles. These EPS-coated particles were used to simulate natural particles, both living and dead. Solubility, protein, and nitrogen content of the EPS suggested it was a slime rather than a capsular polysaccharide. Glycosyl composition of the EPS was glucose and galactose in ?? and ?? linkages, with pyruvate, succinate, and possibly malonate constituent groups. To evaluate the incorporation of C derived from protein associated with the EPS matrix, feeding experiments were conducted using EPS with and without proteins extracted. Black fly larvae incorporated 7.2 ??g EPS C larva-1 d-1 from EPS that did not have proteins extracted, and 19.5 ??g EPS C larva-1 d-1 from EPS with proteins extracted. Carbon in protein that is typically associated with EPS was not solely or selectively incorporated. EPS incorporation rates are similar to rates of cellular bacterial carbon incorporation previously estimated for Ogeechee River black fly larvae. If EPS is generally available as a food resource, the importance of bacteria in detrital food webs may be underestimated by studies that examine only the consumption of bacterial cells.

  18. Structural features and hypoglycemic activities of two polysaccharides from a hot-water extract of Agrocybe cylindracea.

    PubMed

    Kiho, T; Sobue, S; Ukai, S

    1994-01-03

    A glucan (AG-HN1, [alpha]D +24 degrees) and a heteroglycan (AG-HN2, [alpha]D +26 degrees) were isolated from a hot-water extract of the fruiting bodies of Agrocybe cylindracea. The structures were investigated by a combination of chemical and spectroscopic methods. The results indicated that high molecular weight glucan AG-HN1 is primarily a beta-(1-->6)-branched (1-->3)-beta-D-glucan containing small amounts of (1-->4)-linked and (1-->6)-linked glucopyranosyl residues. Low molecular weight heteroglycan AG-HN2 gives galactose, glucose, fucose, and mannose on hydrolysis and appears to be chiefly composed of (1-->6)-linked gluco- and galacto-pyranosyl residues, many of them branched, and various nonreducing terminal residues. AG-HN1 showed a remarkable hypoglycemic activity in both normal and streptozotocin-induced diabetic mice by ip administration, and its activity was higher than that of AG-HN2.

  19. The Relationship of Bacterial Biofilms and Capsular Contracture in Breast Implants

    PubMed Central

    Ajdic, Dragana; Zoghbi, Yasmina; Gerth, David; Panthaki, Zubin J.; Thaller, Seth

    2016-01-01

    Capsular contracture is a common sequelae of implant-based breast augmentation. Despite its prevalence, the etiology of capsular contracture remains controversial. Numerous studies have identified microbial biofilms on various implantable materials, including breast implants. Furthermore, biofilms have been implicated in subclinical infections associated with other surgical implants. In this review, we discuss microbial biofilms as a potential etiology of capsular contracture. The review also outlines the key diagnostic modalities available to identify the possible infectious agents found in biofilm, as well as available preventative and treatment measures. PMID:26843099

  20. Conjugation of Polysaccharide 6B from Streptococcus pneumoniae with Pneumococcal Surface Protein A: PspA Conformation and Its Effect on the Immune Response

    PubMed Central

    Perciani, Catia T.; Barazzone, Giovana C.; Goulart, Cibelly; Carvalho, Eneas; Cabrera-Crespo, Joaquin; Gonçalves, Viviane M.; Leite, Luciana C. C.

    2013-01-01

    Despite the substantial beneficial effects of incorporating the 7-valent pneumococcal conjugate vaccine (PCV7) into immunization programs, serotype replacement has been observed after its widespread use. As there are many serotypes currently documented, the use of a conjugate vaccine relying on protective pneumococcal proteins as active carriers is a promising alternative to expand PCV coverage. In this study, capsular polysaccharide serotype 6B (PS6B) and recombinant pneumococcal surface protein A (rPspA), a well-known protective antigen from Streptococcus pneumoniae, were covalently attached by two conjugation methods. The conjugation methodology developed by our laboratory, employing 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) as an activating agent through carboxamide formation, was compared with reductive amination, a classical methodology. DMT-MM-mediated conjugation was shown to be more efficient in coupling PS6B to rPspA clade 1 (rPspA1): 55.0% of PS6B was in the conjugate fraction, whereas 24% was observed in the conjugate fraction with reductive amination. The influence of the conjugation process on the rPspA1 structure was assessed by circular dichroism. According to our results, both conjugation processes reduced the alpha-helical content of rPspA; reduction was more pronounced when the reaction between the polysaccharide capsule and rPspA1 was promoted between the carboxyl groups than the amine groups (46% and 13%, respectively). Regarding the immune response, both conjugates induced functional anti-rPspA1 and anti-PS6B antibodies. These results suggest that the secondary structure of PspA1, as well as its reactive groups (amine or carboxyl) involved in the linkage to PS6B, may not play an important role in eliciting a protective immune response to the antigens. PMID:23554468

  1. A novel microactuator for microbiopsy in capsular endoscopes

    NASA Astrophysics Data System (ADS)

    Park, Sunkil; Koo, Kyo-in; Bang, Seoung Min; Youp Park, Jeong; Song, Si Young; 'Dan'Cho, Dongil

    2008-02-01

    This paper presents a LiGA (a German acronym for lithographie, galvanoformung, abformung) process based microactuator to be used for microbiopsy in capsular endoscopes. This microactuator is designed to be integrated into a capsular endoscope and to extract tissue samples inside the small gastrointestine which a conventional endoscope cannot reach. The proposed microactuator was fabricated as a cylindrical shape of diameter 10 mm and length 1.8 mm. This actuator consists of three parts: a microbiopsy part with a microspike, an actuating part with a torsion spring and a triggering part with a shape memory alloy (SMA) heating wire and polymer string. In order to extract sample tissue, a microspike in the developed actuator moves forward and backward using the slider-crank mechanism. For low power consumption triggering, a polymer-melting scheme was applied. The SMA heating wire consumed approximately 1.5 V × 160 mA × 1 second (66.67 µWH) for triggering. The precise components of the microactuator were fabricated using the LiGA process in order to overcome the limitations in accuracy of conventional precision machining. The developed microactuator was evaluated by extracting tissue samples from the small intestine of a pig ex vivo, and examining the tissue with hematoxylin and eosin (H&E) staining protocol. The experimental tests demonstrated that the developed microactuator with microspike successfully extracted tissue samples from the pig's small intestines. This paper is an extended version of an oral paper presented at Transducers 2007: 14th International Conference on Solid State Sensors and Actuators, Lyon, France, 10-14 June, 2007.

  2. Composition, Reactivity and Regulation of Extracellular Metal-Reducing Structures (Bacterial Nanowires) Produced by Dissimilatory Metal - Reducing Bacteria

    SciTech Connect

    Beveridge, Terrance J.

    2004-06-01

    Approach. Previously, using conventional and cryoTEM techniques, surface physicochemistry assays, NMR structural analysis, etc., we showed that the structure and composition of Shewanella's lipopolysaccharide (LPS) and capsular polysaccharide (PS) significantly determined overall cell surface physicochemistry. In our study a strong correlation between such macroscopic parameters as surface electronegativity, hydrophobicity or hydrophilicity, and bacterial adhesion to hematite was observed. Rough LPS strains exhibited more than an order higher affinity and maximal sorption capacity to hematite when compared to encapsulated strains. These general trends, however, characterize bacterial adhesion only as a bulk process, being unable to reveal finer mechanisms taking place at the level of an individual cell. Cell surface physicochemical and structural heterogeneity suggests much more complex interactions at the bacterial-mineral interface than predicted by such approaches operating within macroscopic parameters.

  3. Proteomic analysis of scallop hepatopancreatic extract provides insights into marine polysaccharide digestion

    PubMed Central

    Lyu, Qianqian; Jiao, Wenqian; Zhang, Keke; Bao, Zhenmin; Wang, Shi; Liu, Weizhi

    2016-01-01

    Marine polysaccharides are used in a variety of applications, and the enzymes that degrade these polysaccharides are of increasing interest. The main food source of herbivorous marine mollusks is seaweed, and several polysaccharide-degrading enzymes have been extracted from mollusk digestive glands (hepatopancreases). Here, we used a comprehensive proteomic approach to examine the hepatopancreatic proteins of the Zhikong scallop (Chlamys farreri). We identified 435 proteins, the majority of which were lysosomal enzymes and carbohydrate and protein metabolism enzymes. However, several new enzymes related to polysaccharide metabolism were also identified. Phylogenetic and structural analyses of these enzymes suggest that these polysaccharide-degrading enzymes may have a variety of potential substrate specificities. Taken together, our study characterizes several novel polysaccharide-degrading enzymes in the scallop hepatopancreas and provides an enhanced view of these enzymes and a greater understanding of marine polysaccharide digestion. PMID:27982037

  4. Capsular Block Syndrome Following Combined Cataract and Vitrectomy Surgery in a Patient With Intraocular Gas.

    PubMed

    Goodwin, Diamond M; Casey, Richard; Tsui, Irena

    2015-10-01

    The aim of this report is to describe the diagnosis, treatment, and prevention of the rare complication of capsular block syndrome following combined cataract and vitrectomy surgery in a patient with intraocular gas.

  5. Anterior dislocation of an empty capsular bag in a pseudophakic eye: A rare case report

    PubMed Central

    Hwang, Hyung Bin; Yim, Hye Bin; Kim, Hyun Seung

    2015-01-01

    Spontaneous intraocular lens (IOL) dislocation is uncommon in the absence of any ocular areas with zonular weakness or trauma. There have been no reports of spontaneous capsular bag dislocation into the anterior chamber without an IOL. We report a rare, interesting case of spontaneous capsular bag anterior dislocation, without an IOL, into the anterior chamber with no history of genetic disease, ocular trauma, or pseudoexfoliation that might predispose to a zonular abnormality. PMID:25971181

  6. The immunostimulating role of lichen polysaccharides: a review.

    PubMed

    Shrestha, Gajendra; St Clair, Larry L; O'Neill, Kim L

    2015-03-01

    The immune system has capacity to suppress the development or progression of various malignancies including cancer. Research on the immunomodulating properties of polysaccharides obtained from plants, microorganisms, marine organisms, and fungi is growing rapidly. Among the various potential sources, lichens, symbiotic systems involving a fungus and an alga and/or a cyanobacterium, show promise as a potential source of immunomodulating compounds. It is well known that lichens produce an abundance of structurally diverse polysaccharides. However, only a limited number of studies have explored the immunostimulating properties of lichen polysaccharides. Published studies have shown that some lichen polysaccharides enhance production of nitrous oxide (NO) by macrophages and also alter the production levels of various proinflammatory and antiinflammatory cytokines (IL-10, IL-12, IL-1β, TNF-α, and IFN-α/β) by macrophages and dendritic cells. Although there are only a limited number of studies examining the role of lichen polysaccharides, all results suggest that lichen polysaccharides can induce immunomodulatory responses in macrophages and dendritic cells. Thus, a detailed evaluation of immunomodulatory capacity of lichen polysaccharides could provide a unique opportunity for the discovery of novel therapeutic agents.

  7. Compositional studies on succinoglycan-like extracellular water-soluble Rhizobium polysaccharides.

    PubMed

    Ghai, S K

    1981-01-01

    This study reports structural information on extracellular, water-soluble polysaccharides from 5 different strains of Rhizobium, viz. R. trifolii J60, R. meliloti J1017, 202, 204 and 207. All the 5 polysaccharides had glucose and galactose in approximate molar ratio of 7:1. Methylation analysis revealed that the polysaccharides contained (1 leads to 3), (1 leads to 6), (1 leads to 4), (1 leads to 4, 1 leads to 6)-linked D-glucose residues, (1 leads to 3)-linked D-galactose and non-reducing terminal D-glucose attached to pyruvate. This structure was found to be exactly the same as that of succinoglycan, a succinic acid containing water-soluble polysaccharide elaborated by Alcaligenes faecalis var. myxogenes 10C3. The similarity of the structure of polysaccharides of two different Rhizobium species and also to the polysaccharide produced by Alcaligenes are discussed in terms of host specificity.

  8. Biomechanical Comparison of the Latarjet Procedure with and without Capsular Repair

    PubMed Central

    Kleiner, Matthew T.; Payne, William B.; McGarry, Michelle H.; Tibone, James E.

    2016-01-01

    Background The purpose of this study was to determine if capsular repair used in conjunction with the Latarjet procedure results in significant alterations in glenohumeral rotational range of motion and translation. Methods Glenohumeral rotational range of motion and translation were measured in eight cadaveric shoulders in 90° of abduction in both the scapular and coronal planes under the following four conditions: intact glenoid, 20% bony Bankart lesion, modified Latarjet without capsular repair, and modified Latarjet with capsular repair. Results Creation of a 20% bony Bankart lesion led to significant increases in anterior and inferior glenohumeral translation and rotational range of motion (p < 0.005). The Latarjet procedure restored anterior and inferior stability compared to the bony Bankart condition. It also led to significant increases in glenohumeral internal and external rotational range of motion relative to both the intact and bony Bankart conditions (p < 0.05). The capsular repair from the coracoacromial ligament stump to the native capsule did not significantly affect translations relative to the Latarjet condition; however it did cause a significant decrease in external rotation in both the scapular and coronal planes (p < 0.005). Conclusions The Latarjet procedure is effective in restoring anteroinferior glenohumeral stability. The addition of a capsular repair does not result in significant added stability; however, it does appear to have the effect of restricting glenohumeral external rotational range of motion relative to the Latarjet procedure performed without capsular repair. PMID:26929804

  9. The Timing of Implant Exchange in the Development of Capsular Contracture After Breast Reconstruction

    PubMed Central

    Weintraub, Jennifer L.; Kahn, David M.

    2008-01-01

    Objective: Capsular contracture is a common complication associated with reconstructive breast surgery. The optimal time interval between the completion of tissue expansion and placement of the permanent implant is arbitrary and incompletely studied in the literature. The aim of the study was to determine whether the time interval between completion of expansion and placement of the permanent implant would affect the incidence of capsular contracture. Methods: We conducted a retrospective study of 112 patients with breast cancer, including 140 breasts, who underwent postmastectomy tissue expander placement between 1997 and 2004. All patients underwent replacement of tissue expander with a permanent prosthesis. Data were collected retrospectively, including whether the patient smoked, underwent radiation therapy, had saline or silicone implant reconstruction, required reoperation after tissue expander placement or after permanent implant placement, Baker classification, and the interval between completion of expansion and placement of permanent implant. Results: We used a logistic regression model to incorporate the predictors of capsular contracture. Keeping all other predictors constant, we found that the time interval between implant exchange had no effect on capsular contracture. The only significant predictor of capsular contracture was whether the patient required a reoperation after the permanent implant was placed (P = .0001). Conclusions: Allowing the capsule around a tissue expander to mature does not significantly affect development of capsular contracture. However, a complication that necessitates disrupting the periprosthetic capsule of the permanent implant with an operation significantly increases odds of developing contracture. PMID:18587490

  10. Microplasma Induced Cell Morphological Changes and Apoptosis of Ex Vivo Cultured Human Anterior Lens Epithelial Cells - Relevance to Capsular Opacification.

    PubMed

    Recek, Nina; Andjelić, Sofija; Hojnik, Nataša; Filipič, Gregor; Lazović, Saša; Vesel, Alenka; Primc, Gregor; Mozetič, Miran; Hawlina, Marko; Petrovski, Goran; Cvelbar, Uroš

    2016-01-01

    Inducing selective or targeted cell apoptosis without affecting large number of neighbouring cells remains a challenge. A plausible method for treatment of posterior capsular opacification (PCO) due to remaining lens epithelial cells (LECs) by reactive chemistry induced by localized single electrode microplasma discharge at top of a needle-like glass electrode with spot size ~3 μm is hereby presented. The focused and highly-localized atmospheric pressure microplasma jet with electrode discharge could induce a dose-dependent apoptosis in selected and targeted individual LECs, which could be confirmed by real-time monitoring of the morphological and structural changes at cellular level. Direct cell treatment with microplasma inside the medium appeared more effective in inducing apoptosis (caspase 8 positivity and DNA fragmentation) at a highly targeted cell level compared to treatment on top of the medium (indirect treatment). Our results show that single cell specific micropipette plasma can be used to selectively induce demise in LECs which remain in the capsular bag after cataract surgery and thus prevent their migration (CXCR4 positivity) to the posterior lens capsule and PCO formation.

  11. Mapping the polysaccharide degradation potential of Aspergillus niger

    PubMed Central

    2012-01-01

    Background The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required. For each type of hemicellulose, a complex mixture of enzymes is required for complete conversion to fermentable monosaccharides. In plant-biomass degrading fungi, these enzymes are regulated and released by complex regulatory structures. In this study, we present a methodology for evaluating the potential of a given fungus for polysaccharide degradation. Results Through the compilation of information from 203 articles, we have systematized knowledge on the structure and degradation of 16 major types of plant polysaccharides to form a graphical overview. As a case example, we have combined this with a list of 188 genes coding for carbohydrate-active enzymes from Aspergillus niger, thus forming an analysis framework, which can be queried. Combination of this information network with gene expression analysis on mono- and polysaccharide substrates has allowed elucidation of concerted gene expression from this organism. One such example is the identification of a full set of extracellular polysaccharide-acting genes for the degradation of oat spelt xylan. Conclusions The mapping of plant polysaccharide structures along with the corresponding enzymatic activities is a powerful framework for expression analysis of carbohydrate-active enzymes. Applying this network-based approach, we provide the first genome-scale characterization of all genes coding for carbohydrate-active enzymes identified in A. niger. PMID:22799883

  12. Stretch-induced network reconfiguration of collagen fibres in the human facet capsular ligament.

    PubMed

    Zhang, Sijia; Bassett, Danielle S; Winkelstein, Beth A

    2016-01-01

    Biomaterials can display complex spatial patterns of cellular responses to external forces. Revealing and predicting the role of these patterns in material failure require an understanding of the statistical dependencies between spatially distributed changes in a cell's local biomechanical environment, including altered collagen fibre kinematics in the extracellular matrix. Here, we develop and apply a novel extension of network science methods to investigate how excessive tensile stretch of the human cervical facet capsular ligament (FCL), a common source of chronic neck pain, affects the local reorganization of collagen fibres. We define collagen alignment networks based on similarity in fibre alignment angles measured by quantitative polarized light imaging. We quantify the reorganization of these networks following macroscopic loading by describing the dynamic reconfiguration of network communities, regions of the material that display similar fibre alignment angles. Alterations in community structure occur smoothly over time, indicating coordinated adaptation of fibres to loading. Moreover, flexibility, a measure of network reconfiguration, tracks the loss of FCL's mechanical integrity at the onset of anomalous realignment (AR) and regions of AR display altered community structure. These findings use novel network-based techniques to explain abnormal collagen fibre reorganization, a dynamic and coordinated multivariate process underlying tissue failure.

  13. Monoclonal antibodies, carbohydrate-binding modules, and the detection of polysaccharides in plant cell walls.

    PubMed

    Hervé, Cécile; Marcus, Susan E; Knox, J Paul

    2011-01-01

    Plant cell walls are diverse composites of complex polysaccharides. Molecular probes such as monoclonal antibodies (MABs) and carbohydrate-binding modules (CBMs) are important tools to detect and dissect cell wall structures in plant materials. We provide an account of methods that can be used to detect ce