Structural investigation of the capsular polysaccharide produced by a novel Klebsiella serotype (SK1). Location of O-acetyl substituents using NMR and MS techniques.

PubMed

Cescutti, P; Ravenscroft, N; Ng, S; Lam, Z; Dutton, G G

1993-06-21

The capsular polysaccharide of Klebsiella SK1 was investigated by methylation analysis, Smith degradation, and 1H NMR spectroscopy. The oligosaccharides (P1 and P2) obtained by bacteriophage phi SK1 degradation of the polymer were studied by methylation analysis, and 1D- and 2D-NMR spectroscopy. The resulting data showed that the parent repeating unit is a branched pentasaccharide having a structure identical to the revised structure recently proposed for Klebsiella serotype K8 capsular polysaccharide. [Formula: see text] The 2D-NMR data showed that one third of the glucuronic acid residues in the SK1 polymer are acetylated at O-2, O-3, or O-4. FABMS studies confirmed the presence of monoacetylated glucuronic acid residues. Thus, the relationship between the Klebsiella K8 and SK1 polymers is akin to that found for Klebsiella polysaccharides K30 and K33, which have been typed as serologically distinct yet their structures differ only in the degree of acetylation.

Evaluation of lipopolysaccharide and capsular polysaccharide as subunit vaccines against experimental melioidosis.

PubMed

Nelson, Michelle; Prior, Joann L; Lever, M Stephen; Jones, Helen E; Atkins, Timothy P; Titball, Richard W

2004-12-01

Burkholderia pseudomallei is the causative agent of melioidosis, which is a major cause of morbidity and mortality in endemic regions. Currently there is no human vaccine against melioidosis. In this study, LPS or capsular polysaccharide was used to immunize BALB/c mice. The different polysaccharide antigens induced antibody responses. Mice vaccinated with LPS developed predominantly IgM and IgG3 responses. Contrastingly, mice vaccinated with capsular polysaccharide developed a predominantly IgG2b response. After immunization, mice were challenged by the intra-peritoneal route and an increased mean time to death was observed compared with unvaccinated controls. Immunization with LPS provided an optimal protective response. Mice challenged by the aerosol route showed a small increase in the mean time to death compared with the unvaccinated controls. The passive transfer of antigen from immunized into naive mice provided protection against a subsequent challenge. This study is the first time antigens protective by active immunization have been identified and suggests that polysaccharides have potential as vaccine candidates against melioidosis.

Serological response following re-vaccination with Salmonella typhi Vi-capsular polysaccharide vaccines in healthy adult travellers.

PubMed

Roggelin, Louise; Vinnemeier, Christof D; Fischer-Herr, Johanna; Johnson-Weaver, Brandi T; Rolling, Thierry; Burchard, Gerd D; Staats, Herman F; Cramer, Jakob P

2015-08-07

An injectable Vi-capsular polysaccharide vaccine against typhoid fever is available but vaccine-induced immunity tends to wane over time. The phenomenon of immunotolerance or hyporesponsiveness has earlier been described for polysaccharide vaccines such as pneumococcal capsular polysaccharide vaccine and some publications also suggest a possible immunotolerance after revaccination with Vi-capsular polysaccharide vaccines. In this study, post-immunisation antibody concentrations in adult travellers first vaccinated with a Salmonella typhi Vi-capsular polysaccharide vaccine (primary vaccination group) were compared with those having received one or more vaccinations previously (multiple vaccinations group). Vaccines administered were Typherix(®) (GlaxoSmithKline), Typhim Vi(®) (Sanofi Pasteur MSD) or Hepatyrix(®) (GlaxoSmithKline). Blood samples were obtained prior to vaccination (day 0) and on day 28 (-1/+14) after vaccination. Serum Vi-Antigen IgG concentrations were measured by ELISA. Of the 85 subjects included in the per protocol data set, 45 (53%) belonged to the multiple vaccinations group. In both groups, geometric mean antibody concentrations (GMCs) were significantly higher after vaccination than before vaccination. Pre-vaccination GMCs were lower in the primary vaccination group than in the multiple vaccinations group (3.40 μg/ml versus 6.13 μg/ml, P=0.005), while there was no significant difference in the post vaccination GMCs between groups (11.34 μg/ml versus 14.58 μg/ml, P=0.4). In the multiple vaccinations group, vaccination was performed 18 to 57 months after the last vaccination (median 38 months) and there was a negative correlation between time since last vaccination and antibody concentration on day 0. In conclusion, we were not able to demonstrate a relevant immunotolerance after multiple versus primary vaccination with S. typhi Vi-capsular polysaccharide vaccines. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

Capture of Pb2+ and Cu2+ Metal Cations by Neisseria meningitidis-type Capsular Polysaccharides.

PubMed

Ghimire, Sujan; McCarthy, Pumtiwitt C

2018-05-05

Heavy metal pollution of water is a significant environmental and public health concern. Current biological strategies for heavy metal removal from water are performed using microbial biopolymers, including polysaccharides, that are already fully formed. This creates limitations in adapting polysaccharides to increase binding affinity for specific metals. We propose that altering the specificity of polysaccharide-producing enzymes could be beneficial to improving metal capture by modified polysaccharides. We assess binding of Cu 2+ and Pb 2+ metal cations to Neisseria meningitidis -type polysaccharides. All concentrations of metal cations tested were able to completely bind to colominic acid. This polymer is equivalent to the capsular polysaccharide of N. meningitidis serogroup B comprised of a homopolymer of negatively charged sialic acid. There was slightly less binding observed with N. meningitidis serogroup W, which contains repeating units of the neutral sugar galactose and sialic acid. Our work represents the first assessment of the metal-binding properties of these capsular polysaccharides. Future work will seek to optimize metal-binding with Neisseria meningitidis serogroup W polysaccharide.

Relationship between naturally occurring human mucosal and serum antibody to the capsular polysaccharide of Haemophilus influenzae type b.

PubMed

Pichichero, M E; Insel, R A

1982-08-01

The prevalence of natural mucosal antibody to the capsular polysaccharide (polyribosylribitolphosphate [PRP]) of Haemophilus influenzae type b in adults at multiple secretory sites and the relationship between natural serum and mucosal antibodies with respect to their amount and fine binding specificity were examined. All of 16 lactating women had antibody to PRP in serum and mammary samples; 11 of 14 studied had nasal antibody and 12 of 14 had salivary antibody. The amount of serum antibody to PRP in an individual positively correlated with the amount of mucosal antibody at each of the three secretory sites examined, and the antibody amount between certain secretions were also positively correlated. Antibody to PRP that is cross-reactive with Escherichia coli K100 or Streptococcus pneumoniae type 6 capsular polysaccharides was detected in the secretions of seven and one subjects, respectively, but the amount was not correlated with serum cross-reactive antibody.

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

2017-08-18

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.

Two T7-like Bacteriophages, K5-2 and K5-4, Each Encodes Two Capsule Depolymerases: Isolation and Functional Characterization.

PubMed

Hsieh, Pei-Fang; Lin, Hsiao-Hsuan; Lin, Tzu-Lung; Chen, Yi-Yin; Wang, Jin-Town

2017-07-04

Two Klebsiella bacteriophages K5-2 and K5-4, which are able to infect and grow on either capsular types K30/K69 and K5 or K8 and K5 of Klebsiella strains, were isolated and characterized. Each phage contained two open reading frames (ORFs), which encoded two putative capsule depolymerases, respectively. The first ORF encoded tail fiber proteins, which have K30/K69 depolymerase and K8 depolymerase activities. The second ORF encoded hypothetical proteins, which are almost identical in amino acid sequences, and have K5 depolymerase activity. Alcian blue staining of enzyme-treated capsular polysaccharides (CPS) showed that purified depolymerases can cleave purified Klebsiella CPS in vitro and liberate monosaccharaides. Capsule K5 deletion mutants were not lysed by either phage, suggesting that the capsule was essential for phage infection. Bacterial killing was observed when incubated Klebsiella strains with phages but not with purified depolymerases. Treatment with the K5-4 phage significantly increased the survival of mice infected with a K. pneumoniae K5 strain. In conclusion, two dual host-specific Klebsiella phages and their tailspikes exhibit capsule depolymerase activity were characterized. Each phage and phage-encoded depolymerase has specificity for capsular type K30/K69, K8 or K5, and could be used for the typing and treatment of K. pneumoniae infection.

Structural characterization of an all-aminosugar-containing capsular polysaccharide from Colwellia psychrerythraea 34H

PubMed Central

Casillo, Angela; Ståhle, Jonas; Parrilli, Ermenegilda; Sannino, Filomena; Mitchell, Daniel E.; Pieretti, Giuseppina; Gibson, Matthew I.; Marino, Gennaro; Lanzetta, Rosa; Parrilli, Michelangelo; Widmalm, Göran; Tutino, Maria L.; Corsaro, Maria M.

2017-01-01

Colwellia psychrerythraea strain 34H, a Gram-negative bacterium isolated from Arctic marine sediments, is considered a model to study the adaptation to cold environments. Recently, we demonstrated that C. psychrerythraea 34H produces two different extracellular polysaccharides, a capsular polysaccharide and a medium released polysaccharide, which confer cryoprotection to the bacterium. In this study, we report the structure of an additional capsular polysaccharide produced by Colwellia grown at a different temperature. The structure was determined using chemical methods, and one- and two-dimensional NMR spectroscopy. The results showed a trisaccharide repeating unit made up of only amino-sugar residues: N-acetyl-galactosamine, 2,4-diacetamido-2,4,6-trideoxy-glucose (bacillosamine), and 2-acetamido-2-deoxyglucuronic acid with the following structure: →4)-β-d-GlcpNAcA-(1→3)-β-d-QuipNAc4NAc-(1→3)-β-d-GalpNAc-(1→. The 3D model, generated in accordance with 1H,1H-NOE NMR correlations and consisting of ten repeating units, shows a helical structure. In contrast with the other extracellular polysaccharides produced from Colwellia at 4 °C, this molecule displays only a low ice recrystallization inhibition activity. PMID:28161737

Dendritic Cell-Derived Exosomes Express a Streptococcus pneumoniae Capsular Polysaccharide Type 14 Cross-Reactive Antigen That Induces Protective Immunoglobulin Responses against Pneumococcal Infection in Mice

DTIC Science & Technology

2007-01-01

Microbiology. All Rights Reserved. Dendritic Cell-Derived Exosomes Express a Streptococcus pneumoniae Capsular Polysaccharide Type 14 Cross-Reactive...cross-reactive with the capsular polysaccharide of Streptococcus pneumoniae type 14 (Cps14-CRA). Cps14-CRA was localized to the cholesterol-enriched...for S. pneumoniae capsular polysaccharides (Cps) (17). More than 90 Cps sero- types have been described, with no cross-reaction among each other (16

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

Conformational studies of the capsular polysaccharide produced by Neisseria meningitidis group A.

PubMed

Foschiatti, Michela; Hearshaw, Meredith; Cescutti, Paola; Ravenscroft, Neil; Rizzo, R

2009-05-12

The effect of different cations on the conformational and morphological properties of the capsular polysaccharide produced by Neisseria meningitidis group A was investigated. Circular dichroism studies showed that the presence of Na(+), NH4+ or Ca(2+) ions induced different local conformations of the polysaccharide chain through interactions with the phosphodiester group bridging the saccharide residues in the polymer chain. Atomic force microscopy experiments confirmed that the morphology of the polysaccharide chains was different depending on the nature of the counterion. Ammonium ions were associated with the presence of single polymer chains in an elongated conformation, whereas sodium ions favored the folding of the chains into a globular conformation. The addition of calcium ions produced the aggregation of a limited number of globular polysaccharide chains to form a 'toroidal-like' structure.

Peptidoglycan Association of Murein Lipoprotein Is Required for KpsD-Dependent Group 2 Capsular Polysaccharide Expression and Serum Resistance in a Uropathogenic Escherichia coli Isolate

PubMed Central

Diao, Jingyu; Bouwman, Catrien; Yan, Donghong; Kang, Jing; Katakam, Anand K.; Liu, Peter; Pantua, Homer; Abbas, Alexander R.; Nickerson, Nicholas N.; Austin, Cary; Reichelt, Mike; Sandoval, Wendy; Xu, Min

2017-01-01

ABSTRACT Murein lipoprotein (Lpp) and peptidoglycan-associated lipoprotein (Pal) are major outer membrane lipoproteins in Escherichia coli. Their roles in cell-envelope integrity have been documented in E. coli laboratory strains, and while Lpp has been linked to serum resistance in vitro, the underlying mechanism has not been established. Here, lpp and pal mutants of uropathogenic E. coli strain CFT073 showed reduced survival in a mouse bacteremia model, but only the lpp mutant was sensitive to serum killing in vitro. The peptidoglycan-bound Lpp form was specifically required for preventing complement-mediated bacterial lysis in vitro and complement-mediated clearance in vivo. Compared to the wild-type strain, the lpp mutant had impaired K2 capsular polysaccharide production and was unable to respond to exposure to serum by elevating capsular polysaccharide amounts. These properties correlated with altered cellular distribution of KpsD, the predicted outer membrane translocon for “group 2” capsular polysaccharides. We identified a novel Lpp-dependent association between functional KpsD and peptidoglycan, highlighting important interplay between cell envelope components required for resistance to complement-mediated lysis in uropathogenic E. coli isolates. PMID:28536290

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

Bacterially induced mineralization of calcium carbonate: the role of exopolysaccharides and capsular polysaccharides.

PubMed

Ercole, Claudia; Cacchio, Paola; Botta, Anna Lucia; Centi, Valeria; Lepidi, Aldo

2007-02-01

Bacterially induced carbonate mineralization has been proposed as a new method for the restoration of limestones in historic buildings and monuments. We describe here the formation of calcite crystals by extracellular polymeric substances isolated from Bacillus firmus and Bacillus sphaericus. We isolated bacterial outer structures (glycocalix and parietal polymers), such as exopolysaccharides (EPS) and capsular polysaccharides (CPS) and checked for their influence on calcite precipitation. CPS and EPS extracted from both B. firmus and B. sphaericus were able to mediate CaCO3 precipitation in vitro. X-ray microanalysis showed that in all cases the formed crystals were calcite. Scanning electron microscopy showed that the shape of the crystals depended on the fractions utilized. These results suggest the possibility that biochemical composition of CPS or EPS influences the resulting morphology of CaCO3. There were no precipitates in the blank samples. CPS and EPS comprised of proteins and glycoproteins. Positive alcian blue staining also reveals acidic polysaccharides in CPS and EPS fractions. Proteins with molecular masses of 25-40 kDa and 70 kDa in the CPS fraction were highly expressed in the presence of calcium oxalate. This high level of synthesis could be related to the binding of calcium ions and carbonate deposition.

Correlation of E. coli K-1 bacteremia and capsular polysaccharide antigenemia in acute and chronic infection.

PubMed

Stevens, P; Young, L S; Alam, S

1983-09-01

The K-1 polysaccharide is an important virulence factor in human E. coli infections. Using E. coli 016K1, we investigated the kinetic association of bacteremia and K-1 antigenemia in acute lapine and canine infections and in a chronic infection model of neutropenic rats. Additionally, we assessed the presence of K-1 antigenemia in E. coli K-1 bacteremic patients. K-1 was measured by a solid phase radioimmunoassay (RIA) using cross-reactive equine anti-Group B meningococcal IgM. In acute infections, none of the dogs or rabbits developed antigenemia even with a bacteremia of 2 X 10(4) CFU/ml or 5 X 10(5) CFU/ml, respectively. Antigenemia appeared in the rabbit only with an infecting dose of greater than or equal to 5 X 10(8) CFU. In the rat model we observed an initial bacteremia of 10(3) CFU/ml, which increased to 10(6) CFU/ml at 24 hrs. However, antigenemia was most often delayed, appearing in only greater than or equal to 30 hrs postinfection. Percent mortality was directly associated with the degree of bacteremia and antigenemia. In acute human E. coli K-1 bacteremia, 11 of 22 (50%) of patients were positive for K-1 antigenemia. The data demonstrated that K-1 polysaccharide was not usually detectable in the early stages of bacteremia, but occurred only after prolonged infection or very high infecting doses. The RIA to measure K-1 antigenemia would not be a useful diagnostic tool.

Structure of a protective epitope of group B Streptococcus type III capsular polysaccharide.

PubMed

Carboni, Filippo; Adamo, Roberto; Fabbrini, Monica; De Ricco, Riccardo; Cattaneo, Vittorio; Brogioni, Barbara; Veggi, Daniele; Pinto, Vittoria; Passalacqua, Irene; Oldrini, Davide; Rappuoli, Rino; Malito, Enrico; Margarit, Immaculada Y Ros; Berti, Francesco

2017-05-09

Despite substantial progress in the prevention of group B Streptococcus (GBS) disease with the introduction of intrapartum antibiotic prophylaxis, this pathogen remains a leading cause of neonatal infection. Capsular polysaccharide conjugate vaccines have been tested in phase I/II clinical studies, showing promise for further development. Mapping of epitopes recognized by protective antibodies is crucial for understanding the mechanism of action of vaccines and for enabling antigen design. In this study, we report the structure of the epitope recognized by a monoclonal antibody with opsonophagocytic activity and representative of the protective response against type III GBS polysaccharide. The structure and the atomic-level interactions were determined by saturation transfer difference (STD)-NMR and X-ray crystallography using oligosaccharides obtained by synthetic and depolymerization procedures. The GBS PSIII epitope is made by six sugars. Four of them derive from two adjacent repeating units of the PSIII backbone and two of them from the branched galactose-sialic acid disaccharide contained in this sequence. The sialic acid residue establishes direct binding interactions with the functional antibody. The crystal structure provides insight into the molecular basis of antibody-carbohydrate interactions and confirms that the conformational epitope is not required for antigen recognition. Understanding the structural basis of immune recognition of capsular polysaccharide epitopes can aid in the design of novel glycoconjugate vaccines.

A model of high-affinity antibody binding to type III group B Streptococcus capsular polysaccharide.

PubMed

Wessels, M R; Muñoz, A; Kasper, D L

1987-12-01

We recently reported that the single repeating-unit pentasaccharide of type III group B Streptococcus (GBS) capsular polysaccharide is only weakly reactive with type III GBS antiserum. To further elucidate the relationship between antigen-chain length and antigenicity, tritiated oligosaccharides derived from type III capsular polysaccharide were used to generate detailed saturation binding curves with a fixed concentration of rabbit antiserum in a radioactive antigen-binding assay. A graded increase in affinity of antigen-antibody binding was seen as oligosaccharide size increased from 2.6 repeating units to 92 repeating units. These differences in affinity of antibody binding to oligosaccharides of different molecular size were confirmed by immunoprecipitation and competitive ELISA, two independent assays of antigen-antibody binding. Analysis of the saturation binding experiment indicated a difference of 300-fold in antibody-binding affinity for the largest versus the smallest tested oligosaccharides. Unexpectedly, the saturation binding values approached by the individual curves were inversely related to oligosaccharide chain length on a molar basis but equivalent on a weight basis. This observation is compatible with a model in which binding of an immunoglobulin molecule to an antigenic site on the polysaccharide facilitates subsequent binding of antibody to that antigen.

Effect of electrostatic interactions on the ultrafiltration behavior of charged bacterial capsular polysaccharides.

PubMed

Hadidi, Mahsa; Buckley, John J; Zydney, Andrew L

2016-11-01

Charged polysaccharides are used in the food industry, as cosmetics, and as vaccines. The viscosity, thermodynamics, and hydrodynamic properties of these charged polysaccharides are known to be strongly dependent on the solution ionic strength because of both inter- and intramolecular electrostatic interactions. The goal of this work was to quantitatively describe the effect of these electrostatic interactions on the ultrafiltration behavior of several charged capsular polysaccharides obtained from Streptococcus pneumoniae and used in the production of Pneumococcus vaccines. Ultrafiltration data were obtained using various Biomax™ polyethersulfone membranes with different nominal molecular weight cutoffs. Polysaccharide transmission decreased with decreasing ionic strength primarily because of the expansion of the charged polysaccharide associated with intramolecular electrostatic repulsion. Data were in good agreement with a simple theoretical model based on solute partitioning in porous membranes, with the effective size of the different polysaccharide serotypes evaluated using size exclusion chromatography at the same ionic conditions. These results provide fundamental insights and practical guidelines for exploiting the effects of electrostatic interactions during the ultrafiltration of charged polysaccharides. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1531-1538, 2016. © 2016 American Institute of Chemical Engineers.

Staphylococcus aureus capsular polysaccharide types 5 and 8 reduce killing by bovine neutrophils in vitro.

PubMed

Kampen, Annette H; Tollersrud, Tore; Lund, Arve

2005-03-01

Isogenic variants of Staphylococcus aureus strain Reynolds expressing either no capsule or capsular polysaccharide (CP) type 5 (CP5) or type 8 (CP8) were used to assess the effect of CP on bacterial killing and the respiratory burst of bovine neutrophils. The effects of antisera specific for CP5 and CP8 were also evaluated. The killing of live bacteria by isolated neutrophils was quantified in a bactericidal assay, while the respiratory burst after stimulation with live bacteria in whole blood was measured by flow cytometry. The expression of a CP5 or CP8 capsule protected the bacteria from being killed by bovine neutrophils in vitro (P <0.001), and the capsule-expressing variants did not stimulate respiratory burst activity in calf whole blood. The addition of serotype-specific antisera increased the killing of the capsule-expressing bacteria and enhanced their stimulating effect in the respiratory burst assay (P <0.01). When the S. aureus variants were grown under conditions known not to promote capsule expression, there were no significant differences between them. The present study demonstrates that the expression of S. aureus CP5 or CP8 confers resistance to opsonophagocytic killing and prevents the bacteria from inducing respiratory burst of bovine neutrophils in vitro and that these effects can be reversed by the addition of serotype-specific antisera.

Structure of the Type IX Group B Streptococcus Capsular Polysaccharide and Its Evolutionary Relationship with Types V and VII

PubMed Central

Berti, Francesco; Campisi, Edmondo; Toniolo, Chiara; Morelli, Laura; Crotti, Stefano; Rosini, Roberto; Romano, Maria Rosaria; Pinto, Vittoria; Brogioni, Barbara; Torricelli, Giulia; Janulczyk, Robert; Grandi, Guido; Margarit, Immaculada

2014-01-01

The Group B Streptococcus capsular polysaccharide type IX was isolated and purified, and the structure of its repeating unit was determined. Type IX capsule →4)[NeupNAc-α-(2→3)-Galp-β-(1→4)-GlcpNAc-β-(1→6)]-β-GlcpNAc-(1→4)-β-Galp-(1→4)-β-Glcp-(1→ appears most similar to types VII and V, although it contains two GlcpNAc residues. Genetic analysis identified differences in cpsM, cpsO, and cpsI gene sequences as responsible for the differentiation between the three capsular polysaccharide types, leading us to hypothesize that type V emerged from a recombination event in a type IX background. PMID:24990951

Production of polyclonal and monoclonal antibodies against group A, B, and C capsular polysaccharides of Neisseria meningitidis and preparation of latex reagents.

PubMed Central

Nato, F; Mazie, J C; Fournier, J M; Slizewicz, B; Sagot, N; Guibourdenche, M; Postic, D; Riou, J Y

1991-01-01

Polyclonal and monoclonal antibodies against capsular polysaccharides of Neisseria meningitidis serogroups A, B, and C were produced in order to develop immunological reagents allowing both the detection of soluble antigens during meningococcal meningitis and antigenic serogrouping of N. meningitidis cultures. The performance characteristics of monoclonal and polyclonal antibody latex reagents were compared. For the detection of soluble polysaccharide antigen, polyclonal antibody latex reagent was selected for N. meningitidis A and C. The latex reagent prepared with polyclonal antibodies against N. meningitidis B could not detect capsular polysaccharide even at 1 mg/ml. The monoclonal antibody B latex reagent which detected 100 ng of polysaccharide per ml was therefore chosen. For the serogroup identification of N. meningitidis, the use of a confirmatory test results in an overall specificity of 100% with polyclonal or monoclonal antibody latex reagents. PMID:1909346

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

Effects of light wavelengths on extracellular and capsular polysaccharide production by Nostoc flagelliforme.

PubMed

Han, Pei-pei; Sun, Ying; Jia, Shi-ru; Zhong, Cheng; Tan, Zhi-lei

2014-05-25

The influences of different wavelengths of light (red 660nm, yellow 590nm, green 520nm, blue 460nm, purple 400nm) and white light on extracellular polysaccharide (EPS) and capsular polysaccharide (CPS) production by Nostoc flagelliforme in liquid culture were demonstrated in this study. The results showed that, compared with white light, red and blue lights significantly increased both EPS and CPS production while yellow light reduced their production; purple and green lights stimulated EPS production but inhibited CPS formation. Nine constituent monosaccharides and one uronic acid were detected in both EPS and CPS, and their ratios showed significant differences among treatment with different light wavelengths. However, the advanced structure of EPS and CPS from various light conditions did not present obvious difference through Fourier transform infrared spectroscopy and X-ray diffraction characterization. These findings establish a basis for development of high-yielding polysaccharide production process and understanding their regulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Capsular Polysaccharide of Staphylococcus aureus Is Attached to Peptidoglycan by the LytR-CpsA-Psr (LCP) Family of Enzymes*

PubMed Central

Chan, Yvonne Gar-Yun; Kim, Hwan Keun; Schneewind, Olaf; Missiakas, Dominique

2014-01-01

Envelope biogenesis in bacteria involves synthesis of intermediates that are tethered to the lipid carrier undecaprenol-phosphate. LytR-CpsA-Psr (LCP) enzymes have been proposed to catalyze the transfer of undecaprenol-linked intermediates onto the C6-hydroxyl of MurNAc in peptidoglycan, thereby promoting attachment of wall teichoic acid (WTA) in bacilli and staphylococci and capsular polysaccharides (CPS) in streptococci. S. aureus encodes three lcp enzymes, and a variant lacking all three genes (Δlcp) releases WTA from the bacterial envelope and displays a growth defect. Here, we report that the type 5 capsular polysaccharide (CP5) of Staphylococcus aureus Newman is covalently attached to the glycan strands of peptidoglycan. Cell wall attachment of CP5 is abrogated in the Δlcp variant, a defect that is best complemented via expression of lcpC in trans. CP5 synthesis and peptidoglycan attachment are not impaired in the tagO mutant, suggesting that CP5 synthesis does not involve the GlcNAc-ManNAc linkage unit of WTA and may instead utilize another Wzy-type ligase to assemble undecaprenyl-phosphate intermediates. Thus, LCP enzymes of S. aureus are promiscuous enzymes that attach secondary cell wall polymers with discrete linkage units to peptidoglycan. PMID:24753256

Antigenic determinants of Staphylococcus aureus type 5 and type 8 capsular polysaccharide vaccines.

PubMed

Fattom, A I; Sarwar, J; Basham, L; Ennifar, S; Naso, R

1998-10-01

Bacterial capsular polysaccharides (CP) are carbohydrate polymers comprised of repeating saccharide units. Several of these CP have side chains attached to their backbone structures. The side chains may include O-acetyl, phosphate, sialic acid, and other moieties. Those moieties represent the immunodominant epitopes and the most functional ones. The clinically significant Staphylococcus aureus type 5 CP (CP 5) and type 8 CP (CP 8) are comprised of a trisaccharide repeat unit with one O-acetyl group attached to each repeat unit. The immunogenicity of these CP and the functionality of antibodies to the backbone and the O-acetyl moieties were investigated. Immunization with the native CP conjugates (CP with 75% O-acetylation) elicited a high proportion of antibodies directed against the O-acetyl moiety. Nonetheless, all of the vaccinees produced antibodies to the backbone moieties as well. Conjugate vaccines made of de-O-acetylated CP elicited backbone antibodies only. Antibodies to both backbone and O-acetyl groups were found to be opsonic against S. aureus strains which varied in their O-acetyl content. Absorption studies with O-acetylated and de-O-acetylated CP showed that (i) native CP conjugates generated antibodies to both backbone and O-acetyl groups and (ii) O-acetylated isolates were opsonized by both populations of antibodies while the non-O-acetylated strains were predominantly opsonized by the backbone antibodies. These results suggest that S. aureus CP conjugate vaccines elicit multiple populations of antibodies with diverse specificities. Moreover, the antibodies of different specificities (backbone or O-acetyl) are all functional and efficient against the variations in bacterial CP that may occur among clinically significant S. aureus pathogenic isolates.

O-sulfated bacterial polysaccharides with low anticoagulant activity inhibit metastasis.

PubMed

Borgenström, Marjut; Wärri, Anni; Hiilesvuo, Katri; Käkönen, Rami; Käkönen, Sanna; Nissinen, Liisa; Pihlavisto, Marjo; Marjamäki, Anne; Vlodavsky, Israel; Naggi, Annamaria; Torri, Giangiacomo; Casu, Benito; Veromaa, Timo; Salmivirta, Markku; Elenius, Klaus

2007-07-01

Heparin-like polysaccharides possess the capacity to inhibit cancer cell proliferation, angiogenesis, heparanase-mediated cancer cell invasion, and cancer cell adhesion to vascular endothelia via adhesion receptors, such as selectins. The clinical applicability of the antitumor effect of such polysaccharides, however, is compromised by their anticoagulant activity. We have compared the potential of chemically O-sulfated and N,O-sulfated bacterial polysaccharide (capsular polysaccharide from E. COLI K5 [K5PS]) species to inhibit metastasis of mouse B16-BL6 melanoma cells and human MDA-MB-231 breast cancer cells in two in vivo models. We demonstrate that in both settings, O-sulfated K5PS was a potent inhibitor of metastasis. Reducing the molecular weight of the polysaccharide, however, resulted in lower antimetastatic capacity. Furthermore, we show that O-sulfated K5PS efficiently inhibited the invasion of B16-BL6 cells through Matrigel and also inhibited the in vitro activity of heparanase. Moreover, treatment with O-sulfated K5PS lowered the ability of B16-BL6 cells to adhere to endothelial cells, intercellular adhesion molecule-1, and P-selectin, but not to E-selectin. Importantly, O-sulfated K5PSs were largely devoid of anticoagulant activity. These findings indicate that O-sulfated K5PS polysaccharide should be considered as a potential antimetastatic agent.

Selective biotinylation of Neisseria meningitidis group B capsular polysaccharide and application in an improved ELISA for the detection of specific antibodies.

PubMed

Diaz Romero, J; Outschoorn, I

1993-03-15

A method is described for the selective biotinylation of meningococcal capsular polysaccharide from Neisseria meningitidis group B and its application to an enzyme-linked immunoabsorbent assay (ELISA) to detect specific antibodies by immobilization on streptavidin-coated microtiter wells. Capsular polysaccharide from Neisseria meningitidis B has been biotinylated by specific periodate oxidation of terminal residues and condensation of the resulting aldehydes with biotin hydrazide, using a spin-column technique in the intermediate purification steps. The ELISA was optimized employing an extended reaction time between the label alkaline phosphatase and its most common substrate, p-nitrophenyl phosphate, together with evaluation of blocking agents to minimize non-specific binding. Specificity was demonstrated by a direct competitive enzyme immunoassay (EIA).

Levels of Antibodies Specific to Tetanus Toxoid, Haemophilus influenzae Type b, and Pneumococcal Capsular Polysaccharide in Healthy Children and Adults

PubMed Central

Schauer, Uwe; Stemberg, Frank; Rieger, Christian H. L.; Büttner, Wolfgang; Borte, Michael; Schubert, Simone; Möllers, Helga; Riedel, Frank; Herz, Udo; Renz, Harald; Herzog, Wilhelm

2003-01-01

Antibody levels specific for capsular polysaccharides of Streptococcus pneumoniae and Haemophilus influenzae type b (Hib) and for tetanus toxoid were measured in serum samples of 386 age-stratified subjects. The study group consists of healthy adult blood donors and hospitalized children undergoing elective surgery, excluding individuals with a history of infection. In children, anti-tetanus toxoid antibody levels displayed two peaks of 1.20 IU/ml (20.4 mg/liter) and 1.65 IU/ml (28.1 mg/liter) related to the schedule of routine childhood immunization in the first year and at 8 years of age. Eighty percent of the antibodies are of the immunoglobulin G1 (IgG1) isotype. For pneumococcal capsular polysaccharide (PCP), the specific antibody levels represent the acquisition of natural immunity. The initial concentration of 9.2 mg/liter was low in infancy (0.5 to 1 years of age) and remained low until 3 to 4 years of age (14.6 mg/liter). During this period PCP antibodies were almost 100% of the IgG2 subclass. Thereafter, IgG anti-PCP antibody titers increased steadily to adult levels (59.5 mg/liter). The data are intended to provide reference ranges to aid in the interpretation of specific antibody determinations in the clinical setting. PMID:12626443

The non-anticoagulant heparin-like K5 polysaccharide derivative K5-N,OSepi attenuates myocardial ischaemia/reperfusion injury

PubMed Central

Collino, Massimo; Pini, Alessandro; Mastroianni, Rosanna; Benetti, Elisa; Lanzi, Cecilia; Bani, Daniele; Chini, Jacopo; Manoni, Marco; Fantozzi, Roberto; Masini, Emanuela

2012-01-01

Heparin and low molecular weight heparins have been demonstrated to reduce myocardial ischaemia/reperfusion (I/R) injury, although their use is hampered by the risk of haemorrhagic and thrombotic complications. Chemical and enzymatic modifications of K5 polysaccharide have shown the possibility of producing heparin-like compounds with low anticoagulant activity and strong anti-inflammatory effects. Using a rat model of regional myocardial I/R, we investigated the effects of an epimerized N-,O-sulphated K5 polysaccharide derivative, K5-N,OSepi, on infarct size and histological signs of myocardial injury caused by 30 min. ligature of the left anterior descending coronary artery followed by 1 or 24 h reperfusion. K5-N,OSepi (0.1–1 mg/kg given i.v. 15 min. before reperfusion) significantly reduced the extent of myocardial damage in a dose-dependent manner. Furthermore, we investigated the potential mechanism(s) of the cardioprotective effect(s) afforded by K5-N,OSepi. In left ventricular samples, I/R induced mast cell degranulation and a robust increase in lipid peroxidation, free radical-induced DNA damage and calcium overload. Markers of neutrophil infiltration and activation were also induced by I/R in rat hearts, specifically myeloperoxidase activity, intercellular-adhesion-molecule-1 expression, prostaglandin-E2 and tumour-necrosis-factor-α production. The robust increase in oxidative stress and inflammatory markers was blunted by K5-N,OSepi, in a dose-dependent manner, with maximum at 1 mg/kg. Furthermore, K5-N,OSepi administration attenuated the increase in caspase 3 activity, Bid and Bax activation and ameliorated the decrease in expression of Bcl-2 within the ischaemic myocardium. In conclusion, we demonstrate that the cardioprotective effect of the non-anticoagulant K5 derivative K5-N,OSepi is secondary to a combination of anti-apoptotic and anti-inflammatory effects. PMID:22248092

On the specificity of a bacteriophage-borne endoglycanase for the native capsular polysaccharide produced by Klebsiella pneumoniae SK1 and its derived polymers.

PubMed

Cescutti, P; Paoletti, S

1994-02-15

The specificity of the endoglycanase associated with the bacteriophage phi SK1 particles was tested on the native capsular polysaccharide produced by Klebsiella pneumoniae serotype SK1 and on three chemically modified polymers derived from it. The primary structure of the SK1 capsular polysaccharide is: [formula: see text] and the beta 1-3 linkage between the glucose and the galactose residues is the one cleaved by the phage enzyme. The enzyme activity was assayed on the deacetylated polysaccharide and on two derivatives obtained by removal of both the side-chain sugars and of only the alpha-D-galactosyl unit, respectively. The endoglycanase was more active on the deacetylated polysaccharide than on the native one, suggesting that the presence of the acetyl groups interferes with the enzyme-polysaccharide interaction. A possible role of the acetyl groups in the control of the polysaccharide chain length and hence on the rheological behaviour of the capsule cannot be ruled out, as already indicated for other bacterial polysaccharides. On the contrary, the removal of the side chains, either complete or selective, caused the modification of the recognition site in such a way that the enzymatic depolymerization no longer occurred. Therefore, it can be inferred that the phi SK1 endoglycanase requires the presence of both the side chain sugars to exhibit its cleaving activity, although this latter is in the main chain.

Structural determination of the polysaccharide isolated from biofilms produced by a clinical strain of Klebsiella pneumoniae.

PubMed

Cescutti, Paola; De Benedetto, Gianluigi; Rizzo, Roberto

2016-07-22

Klebsiella pneumoniae are Gram negative opportunistic pathogens producing capsular (K) polysaccharides. Seventy-seven different K antigens have been described and they are the basis for K serotyping. Capsular polysaccharides are important virulence factors and have a relevant role for the structure of biofilm communities. Nevertheless, little information is available on the polysaccharides produced in biofilm matrices by Klebsiella spp. In the present study, a clinical isolate of Klebsiella pneumoniae was grown both on cellulose membranes deposited on agar plates, where it formed an adherent biofilm, and in liquid medium, where it formed floating biofilms (flocs). Extraction and purification of the polysaccharide fraction showed that only one main carbohydrate polymer was present in both adherent biofilms and flocs. Composition and linkage analysis, Smith degradation followed by ESI-MS, 1D and 2D NMR spectroscopy revealed that the polysaccharide belong to the type K24 and has the following structure. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genetic and structural elucidation of capsular polysaccharides from Streptococcus pneumoniae serotype 23A and 23B, and comparison to serotype 23F.

PubMed

Ravenscroft, Neil; Omar, Aneesa; Hlozek, Jason; Edmonds-Smith, Cesarina; Follador, Rainer; Serventi, Fabio; Lipowsky, Gerd; Kuttel, Michelle M; Cescutti, Paola; Faridmoayer, Amirreza

2017-10-10

Streptococcus pneumoniae is a globally important encapsulated human pathogen with approximately 100 different serotypes recognized. Serogroup 23 consists of serotype 23F, present in licensed vaccines, and emerging serotypes 23A and 23B. Here, we report the previously unknown structures of the pneumococcal capsular polysaccharides serotype 23A and 23B determined using genetic analysis, NMR spectroscopy, composition and linkage analysis and Smith degradation (of polysaccharide 23A). The structure of the serotype 23A capsular polysaccharide is: →4)-β-D-Glcp-(1→3)-[[α-L-Rhap-(1→2)]-[Gro-(2→P→3)]-β-D-Galp-(1→4)]-β-L-Rhap-(1→. This structure differs from polysaccharide 23F as it features a disaccharide backbone and the di-substituted β-Gal is linked to β-Rha as a side chain. This is due to the different polymerization position catalysed by the unusually divergent repeat unit polymerase Wzy in the 23A cps biosynthesis locus. Steric crowding in 23A, confirmed by molecular models, causes the NMR signal for H-1 of the di-substituted 2,3-β-Gal to resonate in the α-anomeric region. The structure of the serotype 23B capsular polysaccharide is the same as 23F, but without the terminal α-Rha: →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→. The immunodominant terminal α-Rha of 23F is more sterically crowded in 23A and absent in 23B. This may explain the reported typing cross reactions for serotype 23F: slight with 23A and none with 23B. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phosphoproteomics of Klebsiella pneumoniae NTUH-K2044 Reveals a Tight Link between Tyrosine Phosphorylation and Virulence*

PubMed Central

Lin, Miao-Hsia; Hsu, Tung-Li; Lin, Shu-Yu; Pan, Yi-Jiun; Jan, Jia-Tsrong; Wang, Jin-Town; Khoo, Kay-Hooi; Wu, Shih-Hsiung

2009-01-01

Encapsulated Klebsiella pneumoniae is the predominant causative agent of pyogenic liver abscess, an emerging infectious disease that often complicates metastatic meningitis or endophthalmitis. The capsular polysaccharide on K. pneumoniae surface was determined as the key to virulence. Although the regulation of capsular polysaccharide biosynthesis is largely unclear, it was found that protein-tyrosine kinases and phosphatases are involved. Therefore, the identification and characterization of such kinases, phosphatases, and their substrates would advance our knowledge of the underlying mechanism in capsule formation and could contribute to the development of new therapeutic strategies. Here, we analyzed the phosphoproteome of K. pneumoniae NTUH-K2044 with a shotgun approach and identified 117 unique phosphopeptides along with 93 in vivo phosphorylated sites corresponding to 81 proteins. Interestingly, three of the identified tyrosine phosphorylated proteins, namely protein-tyrosine kinase (Wzc), phosphomannomutase (ManB), and undecaprenyl-phosphate glycosyltransferase (WcaJ), were found to be distributed in the cps locus and thus were speculated to be involved in the converging signal transduction of capsule biosynthesis. Consequently, we decided to focus on the lesser studied ManB and WcaJ for mutation analysis. The capsular polysaccharides of WcaJ mutant (WcaJY5F) were dramatically reduced quantitatively, and the LD50 increased by 200-fold in a mouse peritonitis model compared with the wild-type strain. However, the capsular polysaccharides of ManB mutant (ManBY26F) showed no difference in quantity, and the LD50 increased by merely 6-fold in mice test. Our study provided a clear trend that WcaJ tyrosine phosphorylation can regulate the biosynthesis of capsular polysaccharides and result in the pathogenicity of K. pneumoniae NTUH-K2044. PMID:19696081

The Vi Capsular Polysaccharide Enables Salmonella enterica Serovar Typhi to Evade Microbe-Guided Neutrophil Chemotaxis

PubMed Central

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

2014-01-01

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. PMID:25101794

Structural and Biological Characterization of a Capsular Polysaccharide Produced by Staphylococcus haemolyticus▿

PubMed Central

Flahaut, Sigrid; Vinogradov, Evgeny; Kelley, Kathryn A.; Brennan, Shannon; Hiramatsu, Keiichi; Lee, Jean C.

2008-01-01

The DNA sequence of the genome of Staphylococcus haemolyticus JCSC1435 revealed a putative capsule operon composed of 13 genes in tandem. The first seven genes (capABCDEFGSh) showed ≥57% similarity with the Staphylococcus aureus cap5 or cap8 locus. However, the capHIJKLMSh genes are unique to S. haemolyticus and include genes encoding a putative flippase, an aminotransferase, two glycosyltransferases, and a transcriptional regulator. Capsule-like material was readily apparent by immunoelectron microscopy on bacteria harvested in the postexponential phase of growth. Electron micrographs of a JCSC1435 mutant with a deleted cap region lacked the capsule-like material. Both strains produced small amounts of surface-associated material that reacted with antibodies to polyglutamic acid. S. haemolyticus cap genes were amplified from four of seven clinical isolates of S. haemolyticus from humans, and three of these strains produced a serologically cross-reactive capsular polysaccharide. In vitro assays demonstrated that the acapsular mutant strain showed greater biofilm formation but was more susceptible to complement-mediated opsonophagocytic killing than the parent strain. Structural characterization of capsule purified from S. haemolyticus strain JCSC1435 showed a trisaccharide repeating unit: −3-α-l-FucNAc-3-(2-NAc-4-N-Asp-2,4,6-trideoxy-β-d-Glc)-4-α-d-GlcNAc-. This structure is unique among staphylococcal polysaccharides in that its composition includes a trideoxy sugar residue with aspartic acid as an N-acyl substituent. PMID:18165309

Structural and biological characterization of a capsular polysaccharide produced by Staphylococcus haemolyticus.

PubMed

Flahaut, Sigrid; Vinogradov, Evgeny; Kelley, Kathryn A; Brennan, Shannon; Hiramatsu, Keiichi; Lee, Jean C

2008-03-01

The DNA sequence of the genome of Staphylococcus haemolyticus JCSC1435 revealed a putative capsule operon composed of 13 genes in tandem. The first seven genes (capABCDEFG(Sh)) showed > or = 57% similarity with the Staphylococcus aureus cap5 or cap8 locus. However, the capHIJKLM(Sh) genes are unique to S. haemolyticus and include genes encoding a putative flippase, an aminotransferase, two glycosyltransferases, and a transcriptional regulator. Capsule-like material was readily apparent by immunoelectron microscopy on bacteria harvested in the postexponential phase of growth. Electron micrographs of a JCSC1435 mutant with a deleted cap region lacked the capsule-like material. Both strains produced small amounts of surface-associated material that reacted with antibodies to polyglutamic acid. S. haemolyticus cap genes were amplified from four of seven clinical isolates of S. haemolyticus from humans, and three of these strains produced a serologically cross-reactive capsular polysaccharide. In vitro assays demonstrated that the acapsular mutant strain showed greater biofilm formation but was more susceptible to complement-mediated opsonophagocytic killing than the parent strain. Structural characterization of capsule purified from S. haemolyticus strain JCSC1435 showed a trisaccharide repeating unit: -3-alpha-L-FucNAc-3-(2-NAc-4-N-Asp-2,4,6-trideoxy-beta-D-Glc)-4-alpha-D-GlcNAc-. This structure is unique among staphylococcal polysaccharides in that its composition includes a trideoxy sugar residue with aspartic acid as an N-acyl substituent.

Antibodies to Staphylococcus aureus Serotype 8 Capsular Polysaccharide React with and Protect against Serotype 5 and 8 Isolates

PubMed Central

Park, Saeyoung; Gerber, Sabina

2014-01-01

Most Staphylococcus aureus isolates produce either a serotype 5 (CP5) or 8 (CP8) capsular polysaccharide, and the CP antigens are targets for vaccine development. Since CP5 and CP8 have similar trisaccharide repeating units, it is important to identify an epitope shared by both CP5 and CP8. To characterize cross-reactivity between CP5 and CP8, the immunogenicity of CP5 and CP8 conjugate vaccines in mice and rabbits was evaluated by serological assays. Immune sera were also tested for functional activity by in vitro opsonophagocytic-killing assays and a murine bacteremia model. Antibodies to the CP5-cross-reactive material 197 (CRM197) conjugate vaccine bound only to purified CP5. In contrast, antibodies to the CP8-CRM conjugate vaccine reacted with CP8 and (to a lesser extent) CP5. De-O-acetylation of CP5 increased its reactivity with CP8 antibodies. Moreover, CP8 antibodies bound to Pseudomonas aeruginosa O11 lipopolysaccharide, which has a trisaccharide repeating unit similar to that of the S. aureus CPs. CP8-CRM antibodies mediated in vitro opsonophagocytic killing of S. aureus expressing CP5 or CP8, whereas CP5-CRM antibodies were serotype specific. Passive immunization with antiserum to CP5-CRM or CP8-CRM protected mice against bacteremia induced by a serotype 5 S. aureus isolate, suggesting that CP8-CRM elicits antibodies cross-reactive to CP5. The identification of epitopes shared by CP5 and CP8 may inform the rational design of a vaccine to protect against infections caused by CP5- or CP8-producing strains of S. aureus. PMID:25245803

Peptidoglycan Association of Murein Lipoprotein Is Required for KpsD-Dependent Group 2 Capsular Polysaccharide Expression and Serum Resistance in a Uropathogenic Escherichia coli Isolate.

PubMed

Diao, Jingyu; Bouwman, Catrien; Yan, Donghong; Kang, Jing; Katakam, Anand K; Liu, Peter; Pantua, Homer; Abbas, Alexander R; Nickerson, Nicholas N; Austin, Cary; Reichelt, Mike; Sandoval, Wendy; Xu, Min; Whitfield, Chris; Kapadia, Sharookh B

2017-05-23

Murein lipoprotein (Lpp) and peptidoglycan-associated lipoprotein (Pal) are major outer membrane lipoproteins in Escherichia coli Their roles in cell-envelope integrity have been documented in E. coli laboratory strains, and while Lpp has been linked to serum resistance in vitro , the underlying mechanism has not been established. Here, lpp and pal mutants of uropathogenic E. coli strain CFT073 showed reduced survival in a mouse bacteremia model, but only the lpp mutant was sensitive to serum killing in vitro The peptidoglycan-bound Lpp form was specifically required for preventing complement-mediated bacterial lysis in vitro and complement-mediated clearance in vivo Compared to the wild-type strain, the lpp mutant had impaired K2 capsular polysaccharide production and was unable to respond to exposure to serum by elevating capsular polysaccharide amounts. These properties correlated with altered cellular distribution of KpsD, the predicted outer membrane translocon for "group 2" capsular polysaccharides. We identified a novel Lpp-dependent association between functional KpsD and peptidoglycan, highlighting important interplay between cell envelope components required for resistance to complement-mediated lysis in uropathogenic E. coli isolates. IMPORTANCE Uropathogenic E. coli (UPEC) isolates represent a significant cause of nosocomial urinary tract and bloodstream infections. Many UPEC isolates are resistant to serum killing. Here, we show that a major cell-envelope lipoprotein (murein lipoprotein) is required for serum resistance in vitro and for complement-mediated bacterial clearance in vivo This is mediated, in part, through a novel mechanism by which murein lipoprotein affects the proper assembly of a key component of the machinery involved in production of "group 2" capsules. The absence of murein lipoprotein results in impaired production of the capsule layer, a known participant in complement resistance. These results demonstrate an important role for

The form variation of the capsular polysaccharide K1 is not a critical virulence factor of Escherichia coli in a neonatal mouse model of infection.

PubMed

Colino, J; Outschoorn, I

1999-10-01

Escherichia coli K1 is a prevalent cause of Gram-negative neonatal bacteraemia and meningitis in humans. Its capsular polysaccharide K1 (CpsK1) has been identified as an important virulence factor. Nevertheless, the biological and pathogenic implications of its O-acetylated and non-O-acetylated forms are poorly understood. In an attempt to address this, we monitored the expression of both CpsK1 form variants in a neonatal mouse infection model. In the absence of anti-CpsK1 antibodies, no CpsK1 form variant selection was observed during the course of infection. The administration of monoclonal antibodies specific for CpsK1 provided a high level of protection. The monoclonal antibodies that recognized both CpsK1 forms (MGB12) provided protection from up to 850 LD(50). By contrast, the administration of the monoclonal antibodies (MGB15) specific for non-O-acetylated CpsK1 cleared only bacteria expressing this CpsK1 form; a few mouse pups remained bacteraemic, and the bacteria in the blood had O-acetylated CpsK1. In those pups, the infection progressed in a similar fashion to that in mice not treated with monoclonal antibody. Moreover, when the number of bacteria expressing the O-acetylated CpsK1 in the inoculated dose is considered independently, the LD(50)was similar to that for the original strain in pups that had not been treated with monoclonal antibodies (35 CFU). These results suggest that whereas variation in acetylation form per se does not reinforce virulence, it could enable E. coli to avoid immune defenses. This highlights the importance of using highly specific monoclonal antibodies in immunotherapeutic approaches to E. coli K1 neonatal meningitis. Copyright 1999 Academic Press.

Development of a Colloidal Gold-Based Immunochromatographic Strip for Rapid Detection of Klebsiella pneumoniae Serotypes K1 and K2.

PubMed

Siu, L Kristopher; Tsai, Yu-Kuo; Lin, Jung-Chung; Chen, Te-Li; Fung, Chang-Phone; Chang, Feng-Yee

2016-12-01

In this study, a novel colloidal gold-based immunochromatographic strip (ICS) containing anti-Klebsiella pneumoniae capsular polysaccharide polyclonal antibodies was developed to specifically detect K. pneumoniae serotypes K1 and K2. Capsular polysaccharide K1 and K2 antigens were first used to produce polyclonal anti-K1 and anti-K2 antibodies. Reference strains with different serotypes, nontypeable K. pneumoniae strains, and other bacterial species were then used to assess the sensitivity and specificity of these test strips. The detection limit was found to be 10 5 CFU, and the ICSs were stable for 6 months when stored at room temperature. No false-positive or false-negative results were observed, and equivalent results were obtained compared to those of more conventional test methods, such as PCR or serum agglutination. In conclusion, the ICS developed here requires no technical expertise and allows for the specific, rapid, and simultaneous detection of K. pneumoniae serotypes K1 and K2. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

M-Ficolin Binds Selectively to the Capsular Polysaccharides of Streptococcus pneumoniae Serotypes 19B and 19C and of a Streptococcus mitis Strain

PubMed Central

Kjaer, Troels R.; Hansen, Annette G.; Sørensen, Uffe B. S.; Holm, Anne T.; Sørensen, Grith L.; Jensenius, Jens C.

2013-01-01

The three human ficolins (H-, L-, and M-ficolins) and mannan-binding lectin are pattern recognition molecules of the innate immune system mediating activation of the lectin pathway of the complement system. These four human proteins bind to some microorganisms and may be involved in the resolution of infections. We investigated binding selectivity by examining the binding of M-ficolin to a panel of more than 100 different streptococcal strains (Streptococcus pneumoniae and Streptococcus mitis), each expressing distinct polysaccharide structures. M-ficolin binding was observed for three strains only: strains of the pneumococcal serotypes 19B and 19C and a single S. mitis strain expressing a similar polysaccharide structure. The bound M-ficolin, in association with MASP-2, mediated the cleavage of complement factor C4. Binding to the bacteria was inhibitable by N-acetylglucosamine, indicating that the interaction with the bacterial surface takes place via the fibrinogen-like domain. The common N-acetylmannosamine residue present in the structures of the four capsular polysaccharides of group 19 is linked via a phosphodiester bond. This residue is apparently not a ligand for M-ficolin, since the lectin binds to two of the group 19 polysaccharides only. M-ficolin bound strongly to serotype 19B and 19C polysaccharides. In contrast to those of serotypes 19A and 19F, serotype 19B and 19C polysaccharides contain an extra N-acetylmannosamine residue linked via glycoside linkage only. Thus, this extra residue seems to be the M-ficolin ligand. In conclusion, we were able to demonstrate specific binding of M-ficolin to some capsular polysaccharides of the opportunistic pathogen S. pneumoniae and of the commensal bacterium S. mitis. PMID:23184524

Current status of meningococcal group B vaccine candidates: capsular or noncapsular?

PubMed

Diaz Romero, J; Outschoorn, I M

1994-10-01

Meningococcal meningitis is a severe, life-threatening infection for which no adequate vaccine exists. Current vaccines, based on the group-specific capsular polysaccharides, provide short-term protection in adults against serogroups A and C but are ineffective in infants and do not induce protection against group B strains, the predominant cause of infection in western countries, because the purified serogroup B polysaccharide fails to elicit human bactericidal antibodies. Because of the poor immunogenicity of group B capsular polysaccharide, different noncapsular antigens have been considered for inclusion in a vaccine against this serogroup: outer membrane proteins, lipooligosaccharides, iron-regulated proteins, Lip, pili, CtrA, and the immunoglobulin A proteases. Alternatively, attempts to increase the immunogenicity of the capsular polysaccharide have been made by using noncovalent complexes with outer membrane proteins, chemical modifications, and structural analogs. Here, we review the strategies employed for the development of a vaccine for Neisseria meningitidis serogroup B; the difficulties associated with the different approaches are discussed.

Current status of meningococcal group B vaccine candidates: capsular or noncapsular?

PubMed Central

Diaz Romero, J; Outschoorn, I M

1994-01-01

Meningococcal meningitis is a severe, life-threatening infection for which no adequate vaccine exists. Current vaccines, based on the group-specific capsular polysaccharides, provide short-term protection in adults against serogroups A and C but are ineffective in infants and do not induce protection against group B strains, the predominant cause of infection in western countries, because the purified serogroup B polysaccharide fails to elicit human bactericidal antibodies. Because of the poor immunogenicity of group B capsular polysaccharide, different noncapsular antigens have been considered for inclusion in a vaccine against this serogroup: outer membrane proteins, lipooligosaccharides, iron-regulated proteins, Lip, pili, CtrA, and the immunoglobulin A proteases. Alternatively, attempts to increase the immunogenicity of the capsular polysaccharide have been made by using noncovalent complexes with outer membrane proteins, chemical modifications, and structural analogs. Here, we review the strategies employed for the development of a vaccine for Neisseria meningitidis serogroup B; the difficulties associated with the different approaches are discussed. PMID:7834605

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.

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

PubMed

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

2016-10-26

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 M w 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.

Determination of the chemical structure of the capsular polysaccharide of strain B33, a fast-growing soya bean-nodulating bacterium isolated from an arid region of China.

PubMed Central

Rodríguez-Carvajal, M A; Tejero-Mateo, P; Espartero, J L; Ruiz-Sainz, J E; Buendía-Clavería, A M; Ollero, F J; Yang, S S; Gil-Serrano, A M

2001-01-01

We have determined the structure of a polysaccharide from strain B33, a fast-growing bacterium that forms nitrogen-fixing nodules with Asiatic and American soya bean cultivars. On the basis of monosaccharide analysis, methylation analysis, one-dimensional 1H- and 13C-NMR and two-dimensional NMR experiments, the structure was shown to consist of a polymer having the repeating unit -->6)-4-O-methyl-alpha-D-Glcp-(1-->4)-3-O-methyl-beta-D-GlcpA-(1--> (where GlcpA is glucopyranuronic acid and Glcp is glucopyranose). Strain B33 produces a K-antigen polysaccharide repeating unit that does not have the structural motif sugar-Kdx [where Kdx is 3-deoxy-D-manno-2-octulosonic acid (Kdo) or a Kdo-related acid] proposed for different Sinorhizobium fredii strains, all of them being effective with Asiatic soya bean cultivars but unable to form nitrogen-fixing nodules with American soya bean cultivars. Instead, it resembles the K-antigen of S. fredii strain HH303 (rhamnose, galacturonic acid)n, which is also effective with both groups of soya bean cultivars. Only the capsular polysaccharide from strains B33 and HH303 have monosaccharide components that are also present in the surface polysaccharide of Bradyrhizobium elkanii strains, which consists of a 4-O-methyl-D-glucurono-L-rhamnan. PMID:11439101

Effect of growth conditions on production of rhamnose-containing cell wall and capsular polysaccharides by strains of Lactobacillus casei subsp. rhamnosus.

PubMed

Wicken, A J; Ayres, A; Campbell, L K; Knox, K W

1983-01-01

Strains of Lactobacillus casei subsp. rhamnosus possessing two cell wall polysaccharides, a hexosamine-containing H-polysaccharide and a rhamnose-containing R-polysaccharide, were examined for the effect of growth conditions on the production of these two components. In strain NCTC 6375, R- and H-polysaccharides accounted for an estimated 44 and 20%, respectively, of the cell wall for organisms grown in batch culture with glucose as the carbohydrate source. Growth on fructose-containing media reduced the amount of R-polysaccharide by approximately 50% without affecting the amount of H-polysaccharide. Subculture of fructose-grown organisms in glucose restored the original proportions of the two polysaccharides. Galactose- and sucrose-grown cells behaved similarly to glucose-grown cells with respect to polysaccharide production, whereas growth in rhamnose or ribose showed values close to those for fructose-grown cells. Continuous culture of strain NCTC 6375 for more than 100 generations showed a gradual and irreversible reduction of the R-polysaccharide to less than 5% of the cell wall and an increase of the H-polysaccharide to 40% of the cell wall. Other type culture strains of L. casei subsp. rhamnosus, NCIB 7473 and ATCC 7469, behaved similarly in batch and continuous culture. In contrast, strains of L. casei subsp. rhamnosus isolated at the Institute of Dental Research showed phenotypic stability with respect to the relative proportions of R- and H-polysaccharides in both batch and continuous culture. Changes in polysaccharide composition of type culture strains were also mirrored in changes in the immunogenicity of the two components and resistance to the rate of enzymic lysis of whole organisms. For L. casei subsp. rhamnosus strain NCTC 10302 the R-polysaccharide is present entirely as capsular material. The amount of R-polysaccharide produced was also markedly dependent on the carbohydrate component of the medium in batch culture and both dilution rate and

Effect of growth conditions on production of rhamnose-containing cell wall and capsular polysaccharides by strains of Lactobacillus casei subsp. rhamnosus.

PubMed Central

Wicken, A J; Ayres, A; Campbell, L K; Knox, K W

1983-01-01

Strains of Lactobacillus casei subsp. rhamnosus possessing two cell wall polysaccharides, a hexosamine-containing H-polysaccharide and a rhamnose-containing R-polysaccharide, were examined for the effect of growth conditions on the production of these two components. In strain NCTC 6375, R- and H-polysaccharides accounted for an estimated 44 and 20%, respectively, of the cell wall for organisms grown in batch culture with glucose as the carbohydrate source. Growth on fructose-containing media reduced the amount of R-polysaccharide by approximately 50% without affecting the amount of H-polysaccharide. Subculture of fructose-grown organisms in glucose restored the original proportions of the two polysaccharides. Galactose- and sucrose-grown cells behaved similarly to glucose-grown cells with respect to polysaccharide production, whereas growth in rhamnose or ribose showed values close to those for fructose-grown cells. Continuous culture of strain NCTC 6375 for more than 100 generations showed a gradual and irreversible reduction of the R-polysaccharide to less than 5% of the cell wall and an increase of the H-polysaccharide to 40% of the cell wall. Other type culture strains of L. casei subsp. rhamnosus, NCIB 7473 and ATCC 7469, behaved similarly in batch and continuous culture. In contrast, strains of L. casei subsp. rhamnosus isolated at the Institute of Dental Research showed phenotypic stability with respect to the relative proportions of R- and H-polysaccharides in both batch and continuous culture. Changes in polysaccharide composition of type culture strains were also mirrored in changes in the immunogenicity of the two components and resistance to the rate of enzymic lysis of whole organisms. For L. casei subsp. rhamnosus strain NCTC 10302 the R-polysaccharide is present entirely as capsular material. The amount of R-polysaccharide produced was also markedly dependent on the carbohydrate component of the medium in batch culture and both dilution rate and

Capsular profiling of the Cronobacter genus and the association of specific Cronobacter sakazakii and C. malonaticus capsule types with neonatal meningitis and necrotizing enterocolitis.

PubMed

Ogrodzki, P; Forsythe, S

2015-10-08

Cronobacter sakazakii and C. malonaticus can cause serious diseases especially in infants where they are associated with rare but fatal neonatal infections such as meningitis and necrotising enterocolitis. This study used 104 whole genome sequenced strains, covering all seven species in the genus, to analyse capsule associated clusters of genes involved in the biosynthesis of the O-antigen, colanic acid, bacterial cellulose, enterobacterial common antigen (ECA), and a previously uncharacterised K-antigen. Phylogeny of the gnd and galF genes flanking the O-antigen region enabled the defining of 38 subgroups which are potential serotypes. Two variants of the colanic acid synthesis gene cluster (CA1 and CA2) were found which differed with the absence of galE in CA2. Cellulose (bcs genes) were present in all species, but were absent in C. sakazakii sequence type (ST) 13 and clonal complex (CC) 100 strains. The ECA locus was found in all strains. The K-antigen capsular polysaccharide Region 1 (kpsEDCS) and Region 3 (kpsMT) genes were found in all Cronobacter strains. The highly variable Region 2 genes were assigned to 2 homology groups (K1 and K2). C. sakazakii and C. malonaticus isolates with capsular type [K2:CA2:Cell(+)] were associated with neonatal meningitis and necrotizing enterocolitis. Other capsular types were less associated with clinical infections. This study proposes a new capsular typing scheme which identifies a possible important virulence trait associated with severe neonatal infections. The various capsular polysaccharide structures warrant further investigation as they could be relevant to macrophage survival, desiccation resistance, environmental survival, and biofilm formation in the hospital environment, including neonatal enteral feeding tubes.

Solution properties of the capsular polysaccharide produced by Klebsiella pneumoniae SK1.

PubMed

Cescutti, P; Paoletti, S; Navarini, L; Flaibani, A

1993-08-01

The solution properties of the capsular polysaccharide produced by Klebsiella pneumoniae SK1, SK1-CPS, were investigated by various methods. The SK1-CPS repeating unit is a branched pentasaccharide containing one glucuronic acid as single unit side chain; acetyl groups are present as non-carbohydrate substituents on the uronic acid residue in non-stoichiometric amounts. Chiro-optical, potentiometric, viscometric and rheological measurements have been performed in order to characterize the conformational behaviour of the polymer in water and in aqueous salt solutions. Under the investigated experimental conditions, changes of temperature, ionic strength and pH were shown not to induce any cooperative conformational transition. All the results obtained suggest that the solution conformation of SK1-CPS is a random coil with a certain degree of chain flexibility. The removal of the acetyl substituents apparently does not modify the overall conclusions drawn for the native polymer, except for an incipient tendency to aggregation revealed for high salt conditions.

Evidence for rare capsular switching in Streptococcus agalactiae.

PubMed

Martins, Elisabete Raquel; Melo-Cristino, José; Ramirez, Mário

2010-03-01

The polysaccharide capsule is a major antigenic factor in Streptococcus agalactiae (Lancefield group B streptococcus [GBS]). Previous observations suggest that exchange of capsular loci is likely to occur rather frequently in GBS, even though GBS is not known to be naturally transformable. We sought to identify and characterize putative capsular switching events, by means of a combination of phenotypic and genotypic methods, including pulsed-field gel electrophoretic profiling, multilocus sequence typing, and surface protein and pilus gene profiling. We show that capsular switching by horizontal gene transfer is not as frequent as previously suggested. Serotyping errors may be the main reason behind the overestimation of capsule switching, since phenotypic techniques are prone to errors of interpretation. The identified putative capsular transformants involved the acquisition of the entire capsular locus and were not restricted to the serotype-specific central genes, the previously suggested main mechanism underlying capsular switching. Our data, while questioning the frequency of capsular switching, provide clear evidence for in vivo capsular transformation in S. agalactiae, which may be of critical importance in planning future vaccination strategies against this pathogen.

Evidence for Rare Capsular Switching in Streptococcus agalactiae▿

PubMed Central

Martins, Elisabete Raquel; Melo-Cristino, José; Ramirez, Mário

2010-01-01

The polysaccharide capsule is a major antigenic factor in Streptococcus agalactiae (Lancefield group B streptococcus [GBS]). Previous observations suggest that exchange of capsular loci is likely to occur rather frequently in GBS, even though GBS is not known to be naturally transformable. We sought to identify and characterize putative capsular switching events, by means of a combination of phenotypic and genotypic methods, including pulsed-field gel electrophoretic profiling, multilocus sequence typing, and surface protein and pilus gene profiling. We show that capsular switching by horizontal gene transfer is not as frequent as previously suggested. Serotyping errors may be the main reason behind the overestimation of capsule switching, since phenotypic techniques are prone to errors of interpretation. The identified putative capsular transformants involved the acquisition of the entire capsular locus and were not restricted to the serotype-specific central genes, the previously suggested main mechanism underlying capsular switching. Our data, while questioning the frequency of capsular switching, provide clear evidence for in vivo capsular transformation in S. agalactiae, which may be of critical importance in planning future vaccination strategies against this pathogen. PMID:20023016

Development of a Colloidal Gold-Based Immunochromatographic Strip for Rapid Detection of Klebsiella pneumoniae Serotypes K1 and K2

PubMed Central

Siu, L. Kristopher; Tsai, Yu-Kuo; Lin, Jung-Chung; Chen, Te-Li; Fung, Chang-Phone

2016-01-01

In this study, a novel colloidal gold-based immunochromatographic strip (ICS) containing anti-Klebsiella pneumoniae capsular polysaccharide polyclonal antibodies was developed to specifically detect K. pneumoniae serotypes K1 and K2. Capsular polysaccharide K1 and K2 antigens were first used to produce polyclonal anti-K1 and anti-K2 antibodies. Reference strains with different serotypes, nontypeable K. pneumoniae strains, and other bacterial species were then used to assess the sensitivity and specificity of these test strips. The detection limit was found to be 105 CFU, and the ICSs were stable for 6 months when stored at room temperature. No false-positive or false-negative results were observed, and equivalent results were obtained compared to those of more conventional test methods, such as PCR or serum agglutination. In conclusion, the ICS developed here requires no technical expertise and allows for the specific, rapid, and simultaneous detection of K. pneumoniae serotypes K1 and K2. PMID:27707941

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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, andmore » 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.« less

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

PubMed Central

Small, J M; Mitchell, T G

1986-01-01

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 125I, 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. PMID:3536747

The genetic organization of the capsular polysaccharide biosynthesis region of Actinobacillus pleuropneumoniae serotype 15

PubMed Central

ITO, Hiroya; SUEYOSHI, Masuo

2014-01-01

Nucleotide sequence determination and analysis of the cps gene involved in the capsular polysaccharide biosynthesis of Actinobacillus pleuropneumoniae serotype 15 revealed the presence of three open reading frames, designated as cps15ABC genes. At the protein level, Cps15A and Cps15B showed considerably high homology to CpsA (67.0 to 68.7%) and CpsB (31.7 to 36.8%), respectively, of A. pleuropneumoniae serotypes 1, 4 and 12, revealing the common genetic organization of the cps among serotypes 1, 4, 12 and 15. However, Cps15C showed no homology to any proteins of A. pleuropneumoniae serotypes, indicating that cps15C may be specific to serotype 15. This study will provide the basic molecular knowledge necessary for the development of diagnostics and a vaccine for A. pleuropneumoniae serotype 15. PMID:25502540

Development of capsular polysaccharide-based glycoconjugates for immunization against melioidosis and glanders.

PubMed

Burtnick, Mary N; Heiss, Christian; Roberts, Rosemary A; Schweizer, Herbert P; Azadi, Parastoo; Brett, Paul J

2012-01-01

Burkholderia pseudomallei and Burkholderia mallei, the etiologic agents of melioidosis and glanders, respectively, cause severe disease in humans and animals and are considered potential agents of biological warfare and terrorism. Diagnosis and treatment of infections caused by these pathogens can be challenging and, in the absence of chemotherapeutic intervention, acute disease is frequently fatal. At present, there are no human or veterinary vaccines available for immunization against these emerging/re-emerging infectious diseases. One of the long term objectives of our research, therefore, is to identify and characterize protective antigens expressed by B. pseudomallei and B. mallei and use them to develop efficacious vaccine candidates. Previous studies have demonstrated that the 6-deoxy-heptan capsular polysaccharide (CPS) expressed by these bacterial pathogens is both a virulence determinant and a protective antigen. Consequently, this carbohydrate moiety has become an important component of the various subunit vaccines that we are currently developing in our laboratory. In the present study, we describe a reliable method for isolating CPS antigens from O-polysaccharide (OPS) deficient strains of B. pseudomallei; including a derivative of the select agent excluded strain Bp82. Utilizing these purified CPS samples, we also describe a simple procedure for covalently linking these T-cell independent antigens to carrier proteins. In addition, we demonstrate that high titer IgG responses can be raised against the CPS component of such constructs. Collectively, these approaches provide a tangible starting point for the development of novel CPS-based glycoconjugates for immunization against melioidosis and glanders.

Environmentally triggered genomic plasticity and capsular polysaccharide formation are involved in increased ethanol and acetic acid tolerance in Kozakia baliensis NBRC 16680.

PubMed

Brandt, Julia U; Born, Friederike-Leonie; Jakob, Frank; Vogel, Rudi F

2017-08-10

tolerance. The polE gene turned out to be involved in the formation of a cell-associated, capsular polysaccharide, which seems to be essential for increased ethanol/acetic tolerance in contrast to the secreted gum-cluster derived heteropolysaccharide. The genetic and morphological switch could represent an adaptive evolutionary step during the development of K. baliensis NBRC 16680 in course of changing environmental conditions.

Cryptococcus neoformans inhibits nitric oxide synthesis caused by CpG-oligodeoxynucleotide-stimulated macrophages in a fashion independent of capsular polysaccharides.

PubMed

Xiao, Gang; Miyazato, Akiko; Inden, Ken; Nakamura, Kiwamu; Shiratori, Kohei; Nakagawa, Kiyotaka; Miyazawa, Teruo; Suzuki, Kazuo; Kaku, Mitsuo; Kawakami, Kazuyoshi

2008-03-01

Cryptococcus neoformans is eradicated by macrophages via production of NO. Unmethylated CpG-ODN protect mice from infection with this fungal pathogen by inducing IFN-gamma. The present study was designed to elucidate the effect of C. neoformans on the synthesis of NO by alveolar macrophages. For this purpose, MH-S, an alveolar macrophage cell line, was stimulated with CpG-ODN in the presence of IFN-gamma. A highly virulent strain of C. neoformans with thick capsule suppressed the production of NO. Capsular polysaccharides were not essential for this suppression, because there was no difference between acapsular mutant (Cap67) and its parent strain. Physical or close interaction of Cap67 with MH-S was necessary, as shown by the loss of such effect when direct contact was interfered by nitrocellulose membrane. Similar effects were observed by disrupted as well as intact Cap67. Whereas the inhibitory effect of intact Cap67 was completely abrogated by heat treatment, disrupted Cap67 did not receive such influence. Finally, disrupted Cap67 did not show any inhibitory effect on the TLR9-mediated activation of NF-kappaB in a luciferase reporter assay with HEK293T cells, although the TLR4-mediated activation was suppressed. These results revealed that C. neoformans suppressed the synthesis of NO by CpG-ODN and IFN-gamma-stimulated macrophages in a fashion independent of capsular polysaccharides, although the precise mechanism remains to be elucidated.

Dynamics of the Murine Humoral Immune Response to Neisseria meningitidis Group B Capsular Polysaccharide

PubMed Central

Colino, Jesús; Outschoorn, Ingrid

1998-01-01

Immunization with Neisseria meningitidis group B capsular polysaccharide (CpsB) elicited responses in adult mice that showed the typical dynamic characteristics of the response to a thymus-independent antigen, in contrast to the thymus-dependent behavior of antibody responses to CpsC. The former had a short latent period and showed a rapid increase in serum antibodies that peaked at day 5, and immunoglobulin M (IgM) was the major isotype even though IgG (mainly IgG2a and IgG2b) was also detectable. This response was of short duration, and the specific antibodies were rapidly cleared from the circulation. The secondary responses were similar in magnitude, kinetics, IgM predominance, and IgG distribution. Nevertheless, a threefold IgG increase, a correlation between IgM and IgG levels, and dose-dependent secondary responses were observed. Hyperimmunization considerably reinforced these responses: 10-fold for IgM and 300-fold for IgG. This favored isotype switch was accompanied by a progressive change in the subclass distribution to IgG3 (62%) and IgG1 (28%), along with the possible generation of B-cell memory. The results indicate that CpsB is being strictly thymus independent and suggest that unresponsiveness to purified CpsB is due to tolerance. PMID:9453603

Dynamics of the murine humoral immune response to Neisseria meningitis group B capsular polysaccharide.

PubMed

Colino, J; Outschoorn, I

1998-02-01

Immunization with Neisseria meningitidis group B capsular polysaccharide (CpsB) elicited responses in adult mice that showed the typical dynamic characteristics of the response to a thymus-independent antigen, in contrast to the thymus-dependent behavior of antibody responses to CpsC. The former had a short latent period and showed a rapid increase in serum antibodies that peaked at day 5, and immunoglobulin M (IgM) was the major isotype even though IgG (mainly IgG2a and IgG2b) was also detectable. This response was of short duration, and the specific antibodies were rapidly cleared from the circulation. The secondary responses were similar in magnitude, kinetics, IgM predominance, and IgG distribution. Nevertheless, a threefold IgG increase, a correlation between IgM and IgG levels, and dose-dependent secondary responses were observed. Hyperimmunization considerably reinforced these responses: 10-fold for IgM and 300-fold for IgG. This favored isotype switch was accompanied by a progressive change in the subclass distribution to IgG3 (62%) and IgG1 (28%), along with the possible generation of B-cell memory. The results indicate that CpsB is being strictly thymus independent and suggest that unresponsiveness to purified CpsB is due to tolerance.

Nucleotide sequence analysis of a DNA region involved in capsular polysaccharide biosynthesis reveals the molecular basis of the nontypeability of two Actinobacillus pleuropneumoniae isolates.

PubMed

Ito, Hiroya; Ogawa, Torata; Fukamizu, Dai; Morinaga, Yuiko; Kusumoto, Masahiro

2016-11-01

The aim of our study was to reveal the molecular basis of the serologic nontypeability of 2 Actinobacillus pleuropneumoniae field isolates. Nine field strains of A. pleuropneumoniae, the causative agent of porcine pleuropneumonia, were isolated from pigs raised on the same farm and sent to our diagnostic laboratory for serotyping. Seven of the 9 strains were identified as serovar 15 strains by immunodiffusion tests. However, 2 strains, designated FH24-2 and FH24-5, could not be serotyped with antiserum prepared against serovars 1-15. Strain FH24-5 showed positive results in 2 serovar 15-specific PCR tests, whereas strain FH24-2 was only positive in 1 of the 2 PCR tests. The nucleotide sequence analysis of gene clusters involved in capsular polysaccharide biosynthesis of the 2 nontypeable strains revealed that both had been rendered nontypeable by the action of ISApl1, a transposable element of A. pleuropneumoniae belonging to the IS30 family. The results showed that ISApl1 of A. pleuropneumoniae can interfere with both the serologic and molecular typing methods, and that nucleotide sequence analysis across the capsular gene clusters is the best means of determining the cause of serologic nontypeability in A. pleuropneumoniae. © 2016 The Author(s).

Multicenter comparison of levels of antibody to the Neisseria meningitidis group A capsular polysaccharide measured by using an enzyme-linked immunosorbent assay.

PubMed Central

Carlone, G M; Frasch, C E; Siber, G R; Quataert, S; Gheesling, L L; Turner, S H; Plikaytis, B D; Helsel, L O; DeWitt, W E; Bibb, W F

1992-01-01

There is no standard immunoassay for evaluating immune responses to meningococcal vaccines. We developed an enzyme-linked immunosorbent assay to measure total levels of antibody to Neisseria meningitidis group A capsular polysaccharide. Five laboratories measured the antibody levels in six paired pre- and postvaccination serum samples by using the enzyme-linked immunosorbent assay. Methylated human serum albumin was used to bind native group A polysaccharide to microtiter plate surfaces. The between-laboratory coefficients of variation for pre- and postvaccination sera had ranges of 31 to 91 and 17 to 31, respectively. The mean laboratory coefficients of variation for pre- and postvaccination sera, respectively, were 17 and 11 (Molecular Biology Laboratory, Centers for Disease Control), 12 and 15 (Immunodiagnostic Methods Laboratory, Centers for Disease Control), 22 and 19 (Dana-Farber Cancer Institute), 38 and 38 (Bacterial Polysaccharide Laboratory, U.S. Food and Drug Administration), and 11 and 10 (Praxis Biologics, Inc.). Standardization of this enzyme-linked immunosorbent assay should allow interlaboratory comparison of meningococcal vaccine immunogenicity, thus providing a laboratory-based assessment tool for evaluating meningococcal vaccines. PMID:1734048

Conjugate-like immunogens produced as protein capsular matrix vaccines.

PubMed

Thanawastien, Ann; Cartee, Robert T; Griffin, Thomas J; Killeen, Kevin P; Mekalanos, John J

2015-03-10

Capsular polysaccharides are the primary antigenic components involved in protective immunity against encapsulated bacterial pathogens. Although immunization of adolescents and adults with polysaccharide antigens has reduced pathogen disease burden, pure polysaccharide vaccines have proved ineffective at conferring protective immunity to infants and the elderly, age cohorts that are deficient in their adaptive immune responses to such antigens. However, T-cell-independent polysaccharide antigens can be converted into more potent immunogens by chemically coupling to a "carrier protein" antigen. Such "conjugate vaccines" efficiently induce antibody avidity maturation, isotype switching, and immunological memory in immunized neonates. These immune responses have been attributed to T-cell recognition of peptides derived from the coupled carrier protein. The covalent attachment of polysaccharide antigens to the carrier protein is thought to be imperative to the immunological properties of conjugate vaccines. Here we provide evidence that covalent attachment to carrier proteins is not required for conversion of T-independent antigens into T-dependent immunogens. Simple entrapment of polysaccharides or a d-amino acid polymer antigen in a cross-linked protein matrix was shown to be sufficient to produce potent immunogens that possess the key characteristics of conventional conjugate vaccines. The versatility and ease of manufacture of these antigen preparations, termed protein capsular matrix vaccines (PCMVs), will likely provide improvements in the manufacture of vaccines designed to protect against encapsulated microorganisms. This in turn could improve the availability of such vaccines to the developing world, which has shown only a limited capacity to afford the cost of conventional conjugate vaccines.

Immunochemical characterization of the "native" type III polysaccharide of group B Streptococcus

PubMed Central

1976-01-01

The type III polysaccharide of -roup B Streptococcus has been isolated and purified by a method that employs washing of intact cells at neutral pH. That the polysaccharide prepared by this procedure is the "native" type III antigen is suggested by its molecular size in excess of 10(6) daltons, its degradation by acid and heat treatment to a fragment with immunologic characteristics of the classical HCl antigen, and its type-specific serologic activity. The type III polysaccharide in native form contains sialic acid, galactose, glucose, glucosamine, heptose, and mannose. It is acidic in nature, is resistant to neuramindiase degradation, contains no O-acetyl groups, and does not share antigenic determinants with capsular type K1 antigen of Escherichia coli or Group B polysaccharide antigen of Neiserria meningitidis. PMID:55450

High mortality among patients infected with hypervirulent antimicrobial-resistant capsular type K1 Klebsiella pneumoniae strains in Taiwan.

PubMed

Lin, Yi-Tsung; Cheng, Yi-Hsiang; Juan, Chih-Han; Wu, Ping-Feng; Huang, Yi-Wei; Chou, Sheng-Hua; Yang, Tsuey-Ching; Wang, Fu-Der

2018-06-12

Capsular type K1 Klebsiella pneumoniae, highly virulent strains which are common in Asian countries, can cause pyogenic infections. These hypervirulent strains are usually susceptible to most antimicrobials, except for ampicillin. Little is known regarding the clinical and molecular characteristics of antimicrobial-resistant K1 K. pneumoniae strains. This retrospective study evaluated patients infected with capsular type K1 K. pneumoniae strains in a Taiwanese medical centre between April 2013 and March 2016. Antimicrobial-resistant strains were defined based on non-susceptibility to antimicrobial agents except ampicillin. We compared the clinical outcome of patients infected with and without antimicrobial-resistant strains. The in vivo virulence, genetic relatedness, and resistance mechanisms of these hypervirulent antimicrobial-resistant strains were also investigated. A total of 182 capsular type K1 K. pneumoniae strains were identified, including 18 antimicrobial-resistant strains. The 28-day mortality rate among the 18 cases caused by antimicrobial-resistant strains was significantly higher than that among 164 cases caused by antimicrobial-sensitive strains (50% vs. 10.4%, p < 0.001). Infection with antimicrobial-resistant strain independently increased the 28-day mortality risk. Most antimicrobial -resistant strains were not clonally related, and they exhibited high in vivo virulence in a mouse lethality experiment. The major resistance mechanisms involved the presence of β-lactamases and the overexpression of efflux pumps. In conclusion, hypervirulent antimicrobial-resistant capsular type K1 K. pneumoniae strains can predispose to a fatal outcome. These strains may represent an emerging threat to public health in Taiwan. Copyright © 2018. Published by Elsevier B.V.

The genetic organization of the capsular polysaccharide biosynthesis region of Actinobacillus pleuropneumoniae serotype 14

PubMed Central

ITO, Hiroya

2015-01-01

The genetic organization of the gene involved in the capsular polysaccharide (CPS) biosynthesis of Actinobacillus pleuropneumoniae serotype 14 has been determined. The DNA region for the CPS biosynthesis of serotype 14 (cps14) comprised 9 open reading frames, designated as cps14AB1B2B3CDEFG genes, encoding Cps14A to Cps14G protein, respectively. Cps14A was similar to CpsA of A. pleuropneumoniae serotypes 1, 4 and 12; the Cps14B1 and Cps14B2 were similar to CpsB of A. pleuropneumoniae serotypes 1, 4 and 12, suggesting that CPS structure of A. pleuropneumoniae serotype 14 would belong to Group I including A. pleuropneumoniae serotypes 1, 4, 12 and 15. Surprisingly, the overall nucleotide sequence, deduced amino acid sequence, and the genetic organization of the cps14 were nearly identical to those of Actinobacillus suis. This study will provide the molecular basic knowledge for development of diagnostics and vaccine of A. pleuropneumoniae serotype 14. PMID:25648373

Preservation of capsular material of streptococcal cells by specific lectins determined by immunoelectron microscopy.

PubMed

Molinari, A; Orefici, G; Donelli, G; Von Hunolstein, C; Paradisi, S; Arancia, G

1988-09-01

We describe the use of lectins as specific stabilizing agents for the polysaccharide capsular components of two Gram-positive bacteria, Streptococcus agalactiae and Streptococcus bovis. Treatment of bacterial suspensions with wheatgerm agglutinin and concanavalin A allowed better morphological preservation as well as immunoelectron microscopic localization of a capsular component (lipoteichoic acid) by employing specific antibodies and the protein A-gold technique. Data obtained indicate that lectins are useful agents in preserving highly water-soluble capsular components during the electron microscopy procedures for both unembedded and embedded samples.

Reevaluating the serotype II capsular locus of Streptococcus agalactiae.

PubMed

Martins, E R; Melo-Cristino, J; Ramirez, M

2007-10-01

We report a novel sequence of the serotype II capsular locus of group B streptococcus that resolves inconsistencies among the results of various groups and the sequence in GenBank. This locus was found in diverse lineages and presents genes consistent with the complete synthesis of the type II polysaccharide.

Antiangiogenic activity of semisynthetic biotechnological heparins: low-molecular-weight-sulfated Escherichia coli K5 polysaccharide derivatives as fibroblast growth factor antagonists.

PubMed

Presta, Marco; Oreste, Pasqua; Zoppetti, Giorgio; Belleri, Mirella; Tanghetti, Elena; Leali, Daria; Urbinati, Chiara; Bugatti, Antonella; Ronca, Roberto; Nicoli, Stefania; Moroni, Emanuela; Stabile, Helena; Camozzi, Maura; Hernandez, German Andrés; Mitola, Stefania; Dell'Era, Patrizia; Rusnati, Marco; Ribatti, Domenico

2005-01-01

Low-molecular-weight heparin (LMWH) exerts antitumor activity in clinical trials. The K5 polysaccharide from Escherichia coli has the same structure as the heparin precursor. Chemical and enzymatic modifications of K5 polysaccharide lead to the production of biotechnological heparin-like compounds. We investigated the fibroblast growth factor-2 (FGF2) antagonist and antiangiogenic activity of a series of LMW N,O-sulfated K5 derivatives. Surface plasmon resonance analysis showed that LMW-K5 derivatives bind FGF2, thus inhibiting its interaction with heparin immobilized to a BIAcore sensor chip. Interaction of FGF2 with tyrosine-kinase receptors (FGFRs), heparan sulfate proteoglycans (HSPGs), and alpha(v)beta3 integrin is required for biological response in endothelial cells. Similar to LMWH, LMW-K5 derivatives abrogate the formation of HSPG/FGF2/FGFR ternary complexes by preventing FGF2-mediated attachment of FGFR1-overexpressing cells to HSPG-bearing cells and inhibit FGF2-mediated endothelial cell proliferation. However, LMW-K5 derivatives, but not LMWH, also inhibit FGF2/alpha(v)beta3 integrin interaction and consequent FGF2-mediated endothelial cell sprouting in vitro and angiogenesis in vivo in the chick embryo chorioallantoic membrane. LMW N,O-sulfated K5 derivatives affect both HSPG/FGF2/FGFR and FGF2/alpha(v)beta3 interactions and are endowed with FGF2 antagonist and antiangiogenic activity. These compounds may provide the basis for the design of novel LMW heparin-like angiostatic compounds.

Capsular Polysaccharide Interferes with Biofilm Formation by Pasteurella multocida Serogroup A

PubMed Central

Petruzzi, Briana; Briggs, Robert E.; Swords, W. Edward; De Castro, Cristina; Molinaro, Antonio

2017-01-01

ABSTRACT Pasteurella multocida is an important multihost animal and zoonotic pathogen that is capable of causing respiratory and multisystemic diseases, bacteremia, and bite wound infections. The glycosaminoglycan capsule of P. multocida is an essential virulence factor that protects the bacterium from host defenses. However, chronic infections (such as swine atrophic rhinitis and the carrier state in birds and other animals) may be associated with biofilm formation, which has not been characterized in P. multocida. Biofilm formation by clinical isolates was inversely related to capsule production and was confirmed with capsule-deficient mutants of highly encapsulated strains. Capsule-deficient mutants formed biofilms with a larger biomass that was thicker and smoother than the biofilm of encapsulated strains. Passage of a highly encapsulated, poor-biofilm-forming strain under conditions that favored biofilm formation resulted in the production of less capsular polysaccharide and a more robust biofilm, as did addition of hyaluronidase to the growth medium of all of the strains tested. The matrix material of the biofilm was composed predominately of a glycogen exopolysaccharide (EPS), as determined by gas chromatography-mass spectrometry, nuclear magnetic resonance, and enzymatic digestion. However, a putative glycogen synthesis locus was not differentially regulated when the bacteria were grown as a biofilm or planktonically, as determined by quantitative reverse transcriptase PCR. Therefore, the negatively charged capsule may interfere with biofilm formation by blocking adherence to a surface or by preventing the EPS matrix from encasing large numbers of bacterial cells. This is the first detailed description of biofilm formation and a glycogen EPS by P. multocida. PMID:29162713

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.

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. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

The Opportunistic Pathogen Vibrio vulnificus Produces Outer Membrane Vesicles in a Spatially Distinct Manner Related to Capsular Polysaccharide

PubMed Central

Hampton, Cheri M.; Guerrero-Ferreira, Ricardo C.; Storms, Rachel E.; Taylor, Jeannette V.; Yi, Hong; Gulig, Paul A.; Wright, Elizabeth R.

2017-01-01

Vibrio vulnificus, a bacterial species that inhabits brackish waters, is an opportunistic pathogen of humans. V. vulnificus infections can cause acute gastroenteritis, invasive septicemia, tissue necrosis, and potentially death. Virulence factors associated with V. vulnificus include the capsular polysaccharide (CPS), lipopolysaccharide, flagellum, pili, and outer membrane vesicles (OMVs). The aims of this study were to characterize the morphology of V. vulnificus cells and the formation and arrangement of OMVs using cryo-electron microscopy (cryo-EM). cryo-EM and cryo-electron tomography imaging of V. vulnificus strains grown in liquid cultures revealed the presence of OMVs (diameters of ∼45 nm for wild-type, ∼30 nm for the unencapsulated mutant, and ∼50 nm for the non-motile mutant) in log-phase growth. Production of OMVs in the stationary growth phase was limited and irregular. The spacing of the OMVs around the wild-type cells was in regular, concentric rings. In wild-type cells and a non-motile mutant, the spacing between the cell envelope and the first ring of OMVs was ∼200 nm; this spacing was maintained between subsequent OMV layers. The size, arrangement, and spacing of OMVs in an unencapsulated mutant was irregular and indicated that the polysaccharide chains of the capsule regulate aspects of OMV production and order. Together, our results revealed the distinctive organization of V. vulnificus OMVs that is affected by expression of the CPS. PMID:29163452

Cytidine Diphosphoramidate Kinase: An Enzyme Required for the Biosynthesis of the O-Methyl Phosphoramidate Modification in the Capsular Polysaccharides of Campylobacter jejuni.

PubMed

Taylor, Zane W; Raushel, Frank M

2018-04-17

Campylobacter jejuni, a leading cause of gastroenteritis, produces a capsular polysaccharide that is derivatized with a unique O-methyl phosphoramidate (MeOPN) modification. This modification contributes to serum resistance and invasion of epithelial cells. Previously, the first three biosynthetic steps for the formation of MeOPN were elucidated. The first step is catalyzed by a novel glutamine kinase (Cj1418), which catalyzes the adenosine triphosphate (ATP)-dependent phosphorylation of the amide nitrogen of l-glutamine. l-Glutamine phosphate is used by cytidine triphosphate (CTP):phosphoglutamine cytidylyltransferase (Cj1416) to displace pyrophosphate from CTP to generate cytidine diphosphate (CDP)-l-glutamine, which is then hydrolyzed by γ-glutamyl-CDP-amidate hydrolase (Cj1417) to form cytidine diphosphoramidate (CDP-NH 2 ). Here, we show that Cj1415 catalyzes the ATP-dependent phosphorylation of CDP-NH 2 to form 3'-phospho-cytidine-5'-diphosphoramidate. Cj1415 will also catalyze the phosphorylation of adenosine diphosphoramidate (ADP-NH 2 ) and uridine diphosphoramidate (UDP-NH 2 ) but at significantly reduced rates. It is proposed that Cj1415 be named cytidine diphosphoramidate kinase.

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

Clinical and serological responses following primary and booster immunization with Salmonella typhi Vi capsular polysaccharide vaccines.

PubMed

Keitel, W A; Bond, N L; Zahradnik, J M; Cramton, T A; Robbins, J B

1994-01-01

Clinical and serum antibody responses following intramuscular injection of two formulations of Salmonella typhi Vi capsular polysaccharide (Vi) were assessed in a double-blind evaluation. Healthy adults were randomly assigned to receive a 25 micrograms dose of liquid (Vi-Liq; n = 182) or freeze-dried Vi vaccine (Vi-Lyoph; n = 55), or placebo (n = 86). Erythema and/or induration > or = 1 cm in diameter at the injection site developed in 13/182 (7%) of Vi-Liq and 3/55 (5%) of Vi-Lyoph recipients (not significant, n.s.). Fever (oral temperature > or = 100 degrees F (37.8 degrees C)) occurred in < 2% of vaccinees. The frequencies of rises of fourfold or greater and of maximal Vi antibody levels were similar in the two vaccine groups. Fourfold or greater rises in serum Vi antibody levels (RIA) developed in 53% of Vi-Lyoph and 60% of Vi-Liq recipients by 1 week (n.s.), and 98 and 93%, respectively, by 1 month (n.s.). The frequencies of adverse reactions and mean Vi antibody levels following booster immunization with Vi-Liq 27 to 34 months after primary immunization (n = 55) were similar to those observed following primary immunization, although subjects given a booster dose were more likely to develop local reactions > or = 1 cm in diameter than those given a first dose (10/55 versus 13/182, p = 0.013 by the chi 2 test). Primary and booster immunizations with the Vi vaccines are well tolerated in healthy adults; mean Vi antibody levels remain significantly elevated for up to 34 months after primary immunization.

Cross-protection in Neisseria meningitidis serogroups Y and W polysaccharides: A comparative conformational analysis.

PubMed

Kuttel, Michelle M; Timol, Zaheer; Ravenscroft, Neil

2017-06-29

The capsular polysaccharide is the main virulence factor in meningococcus. The capsular polysaccharides for meningococcal serogroups Y and W are almost identical polymers of hexose-sialic acid, suggesting the possibility of cross-protection between group Y and W vaccines. However, early studies indicated that they elicit different levels of cross-protection. Here we explore the conformations of the meningococcal Y and W polysaccharides with molecular dynamics simulations of three repeating unit oligosaccharide strands. We find differences in Y and W antigen conformation: the Y polysaccharide has a single dominant conformation, whereas W exhibits a family of conformations including the Y conformation. This result is supported by our NMR NOESY analysis, which indicates key close contacts for W that are not present in Y. These conformational differences provide an explanation for the different levels of cross-protection measured for the Y and W monovalent vaccines and the high group W responses observed in HibMenCY-TT vaccinees. Copyright © 2017 Elsevier Ltd. All rights reserved.

Visualization of bacterial polysaccharides by scanning transmission electron microscopy.

PubMed

Wolanski, B S; McAleer, W J; Hilleman, M R

1983-04-01

Highly purified capsular polysaccharides of Neisseria meningitidis groups A, B, and C have been visualized by high resolution Scanning Transmission Electron Microscopy (STEM). Spheroidal macromolecules approximately 200 A in diameter are characteristic of the Meningococcus A and C polysaccharides whereas filaments that are 400-600 A in length are found in Meningococcus B polysaccharide preparations. Filaments are occasionally found associated with the spheroidal Meningococcus A and C polysaccharides and it is proposed that these structures are composed of a long (1-4 microns) filament or filaments that are arranged in spheroidal molecules or micelles of high molecular weight. The Meningococcus B polysaccharide, by contrast, is a short flexuous filament or strand of relatively low molecular weight. A relationship between morphology and antigenicity is proposed.

The elevation effect on water-soluble polysaccharides and DPPH free radical scavenging activity of Ganoderma lucidum K

NASA Astrophysics Data System (ADS)

Darsih, C.; Apriyana, W.; Nur Hayati, S.; Taufika Rosyida, V.; Hernawan; Dewi Poeloengasih, C.

2017-02-01

Water soluble polysaccharide is one of the important phytochemical in Ganoderma lucidum K. Phytochemicals in the plants, microorganisms, and plants were affected by internal and external factors. The objective of the research was to evaluate the effect of elevation on the water-soluble polysaccharides and its DPPH radical scavenging activity. We found that the water-polysaccharides in mushroom from Godean (elevation <100 mamsl) (35.28 ± 0.31%) higher than Kaliurang (elevation 800 mamsl) (25.17 ± 1.85%). The DPPH free radical scavenging activity of Ganoderma lucidum K from Godean (IC50 11.5 ± 0.29 mg/mL) higher than Kaliurang (IC50 14.4 ± 0.27%).

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

The structure of the acidic exopolysaccharide produced by Pseudomonas "gingeri" strain Pf9.

PubMed

Cescutti, P; Osman, S F; Fett, W F; Weisleder, D

1995-10-02

The structure of the acidic exopolysaccharide produced by the mushroom pathogen Pseudomonas "gingeri" strain Pf9, a bacterium which causes ginger blotch, was investigated by chemical analysis, mass spectrometry and 1D and 2D NMR spectroscopy. The polysaccharide consists of the linear trisaccharide repeating unit [formula: see text] where the cyclic pyruvic acetal groups at O-4 and O-6 of the mannopyranosyl residues have the S-configuration. Methylation analysis under neutral conditions and NMR data showed that the mannose residues are acetylated at O-2. This exopolysaccharide has the same structure as the E. coli K55 capsular polysaccharide and differs from the Klebsiella K5 capsular polysaccharide only in the position of acetylation (C-2 of the glucopyranose residue).

EDTA Inhibits Biofilm Formation, Extracellular Vesicular Secretion, and Shedding of the Capsular Polysaccharide Glucuronoxylomannan by Cryptococcus neoformans

PubMed Central

Robertson, Emma J.; Wolf, Julie M.

2012-01-01

The fungal pathogen Cryptococcus neoformans can grow as a biofilm on a range of synthetic and prosthetic materials. Cryptococcal biofilm formation can complicate the placement of shunts used to relieve increased intracranial pressure in cryptococcal meningitis and can serve as a nidus for chronic infection. Biofilms are generally advantageous to pathogens in vivo, as they can confer resistance to antimicrobial compounds, including fluconazole and voriconazole in the case of C. neoformans. EDTA can inhibit biofilm formation by several microbes and enhances the susceptibility of biofilms to antifungal drugs. In this study, we evaluated the effect of sublethal concentrations of EDTA on the growth of cryptococcal biofilms. EDTA inhibited biofilm growth by C. neoformans, and the inhibition could be reversed by the addition of magnesium or calcium, implying that the inhibitory effect was by divalent cation starvation. EDTA also reduced the amount of the capsular polysaccharide glucuronoxylomannan shed into the biofilm matrix and decreased vesicular secretion from the cell, thus providing a potential mechanism for the inhibitory effect of this cation-chelating compound. Our data imply that the growth of C. neoformans biofilms requires the presence of divalent metals in the growth medium and suggest that cations are required for the export of materials needed for biofilm formation, possibly including extracellular vesicles. PMID:22941091

Streptococcus suis capsular polysaccharide inhibits phagocytosis through destabilization of lipid microdomains and prevents lactosylceramide-dependent recognition.

PubMed

Houde, Mathieu; Gottschalk, Marcelo; Gagnon, Fleur; Van Calsteren, Marie-Rose; Segura, Mariela

2012-02-01

Streptococcus suis type 2 is a major swine pathogen and a zoonotic agent, causing meningitis in both swine and humans. S. suis infects the host through the respiratory route, reaches the bloodstream, and persists until breaching into the central nervous system. The capsular polysaccharide (CPS) of S. suis type 2 is considered a key virulence factor of the bacteria. Though CPS allows S. suis to adhere to the membrane of cells of the immune system, it provides protection against phagocytosis. In fact, nonencapsulated mutants are easily internalized and killed by macrophages and dendritic cells. The objective of this work was to study the molecular mechanisms by which the CPS of S. suis prevents phagocytosis. By using latex beads covalently linked with purified CPS, it was shown that CPS itself was sufficient to inhibit entry of both latex beads and bystander fluorescent beads into macrophages. Upon contact with macrophages, encapsulated S. suis was shown to destabilize lipid microdomains at the cell surface, to block nitric oxide (NO) production during infection, and to prevent lactosylceramide accumulation at the phagocytic cup during infection. In contrast, the nonencapsulated mutant was easily internalized via lipid rafts, in a filipin-sensitive manner, leading to lactosylceramide recruitment and strong NO production. This is the first report to identify a role for CPS in lipid microdomain stability and to recognize an interaction between S. suis and lactosylceramide in phagocytes.

Fine Specificity and Cross-Reactions of Monoclonal Antibodies to Group B Streptococcal Capsular Polysaccharide Type III

PubMed Central

Pincus, Seth H.; Moran, Emily; Maresh, Grace; Jennings, Harold J.; Pritchard, David G.; Egan, Marianne L.; Blixt, Ola

2012-01-01

Group B streptococcus (GBS) is a major cause of neonatal sepsis and meningitis. Despite aggressive campaigns using antenatal prophylactic antibiotic therapy, infections continue. Developing an effective maternal vaccine is a public health priority. Antibody (Ab) to the capsular polysaccharide (CPS) is considered the dominant “protective” immune mediator. Here we study the fine specificity and potential host reactivity of a panel of well-characterized murine monoclonal Abs against the type III CPS by examining the binding of the Abs to intact and neuraminidase-digested GBS, purified CPS, synthetic carbohydrate structures, and cells. The results showed marked differences in the fine specificity among these mAbs to a single carbohydrate structure. Cross-reactions with synthetic GD3 and GT3 carbohydrates, representing structures found on surfaces of neural and developing cells, were demonstrated using carbohydrate array technology. The anti-CPSIII mAbs did not react with cells expressing GD3 and GT3, nor did mAbs specific for the host carbohydrates cross-react with GBS, raising questions about the physiological relevance of this cross-reaction. But in the process of these investigations, we serendipitously demonstrated cross-reactions of some anti-CPSIII mAbs with antigens, likely carbohydrates, found on human leukocytes. These studies suggest caution in the development of a maternal vaccine to prevent infection by this important human pathogen. PMID:22634296

Fine specificity and cross-reactions of monoclonal antibodies to group B streptococcal capsular polysaccharide type III.

PubMed

Pincus, Seth H; Moran, Emily; Maresh, Grace; Jennings, Harold J; Pritchard, David G; Egan, Marianne L; Blixt, Ola

2012-07-06

Group B streptococcus (GBS) is a major cause of neonatal sepsis and meningitis. Despite aggressive campaigns using antenatal prophylactic antibiotic therapy, infections continue. Developing an effective maternal vaccine is a public health priority. Antibody (Ab) to the capsular polysaccharide (CPS) is considered the dominant "protective" immune mediator. Here we study the fine specificity and potential host reactivity of a panel of well-characterized murine monoclonal Abs against the type III CPS by examining the binding of the Abs to intact and neuraminidase-digested GBS, purified CPS, synthetic carbohydrate structures, and cells. The results showed marked differences in the fine specificity among these mAbs to a single carbohydrate structure. Cross-reactions with synthetic GD3 and GT3 carbohydrates, representing structures found on surfaces of neural and developing cells, were demonstrated using carbohydrate array technology. The anti-CPS(III) mAbs did not react with cells expressing GD3 and GT3, nor did mAbs specific for the host carbohydrates cross-react with GBS, raising questions about the physiological relevance of this cross-reaction. But in the process of these investigations, we serendipitously demonstrated cross-reactions of some anti-CPS(III) mAbs with antigens, likely carbohydrates, found on human leukocytes. These studies suggest caution in the development of a maternal vaccine to prevent infection by this important human pathogen. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

Chemical polyglycosylation and nanolitre detection enables single-molecule recapitulation of bacterial sugar export

NASA Astrophysics Data System (ADS)

Kong, Lingbing; Almond, Andrew; Bayley, Hagan; Davis, Benjamin G.

2016-05-01

The outermost protective layer of both Gram-positive and Gram-negative bacteria is composed of bacterial capsular polysaccharides. Insights into the interactions between the capsular polysaccharide and its transporter and the mechanism of sugar export would not only increase our understanding of this key process, but would also help in the design of novel therapeutics to block capsular polysaccharide export. Here, we report a nanolitre detection system that makes use of the bilayer interface between two droplets, and we use this system to study single-molecule recapitulation of sugar export. A synthetic strategy of polyglycosylation based on tetrasaccharide monomers enables ready synthetic access to extended fragments of K30 oligosaccharides and polysaccharides. Examination of the interactions between the Escherichia coli sugar transporter Wza and very small amounts of fragments of the K30 capsular polysaccharide substrate reveal the translocation of smaller but not larger fragments. We also observe capture events that occur only on the intracellular side of Wza, which would complement coordinated feeding by adjunct biosynthetic machinery.

Effects of lipopolysaccharide biosynthesis mutations on K1 polysaccharide association with the Escherichia coli cell surface.

PubMed

Jiménez, Natalia; Senchenkova, Sofya N; Knirel, Yuriy A; Pieretti, Giuseppina; Corsaro, Maria M; Aquilini, Eleonora; Regué, Miguel; Merino, Susana; Tomás, Juan M

2012-07-01

The presence of cell-bound K1 capsule and K1 polysaccharide in culture supernatants was determined in a series of in-frame nonpolar core biosynthetic mutants from Escherichia coli KT1094 (K1, R1 core lipopolysaccharide [LPS] type) for which the major core oligosaccharide structures were determined. Cell-bound K1 capsule was absent from mutants devoid of phosphoryl modifications on L-glycero-D-manno-heptose residues (HepI and HepII) of the inner-core LPS and reduced in mutants devoid of phosphoryl modification on HepII or devoid of HepIII. In contrast, in all of the mutants, K1 polysaccharide was found in culture supernatants. These results were confirmed by using a mutant with a deletion spanning from the hldD to waaQ genes of the waa gene cluster to which individual genes were reintroduced. A nuclear magnetic resonance (NMR) analysis of core LPS from HepIII-deficient mutants showed an alteration in the pattern of phosphoryl modifications. A cell extract containing both K1 capsule polysaccharide and LPS obtained from an O-antigen-deficient mutant could be resolved into K1 polysaccharide and core LPS by column chromatography only when EDTA and deoxycholate (DOC) buffer were used. These results suggest that the K1 polysaccharide remains cell associated by ionically interacting with the phosphate-negative charges of the core LPS.

Effects of Lipopolysaccharide Biosynthesis Mutations on K1 Polysaccharide Association with the Escherichia coli Cell Surface

PubMed Central

Jiménez, Natalia; Senchenkova, Sofya N.; Knirel, Yuriy A.; Pieretti, Giuseppina; Corsaro, Maria M.; Aquilini, Eleonora; Regué, Miguel; Merino, Susana

2012-01-01

The presence of cell-bound K1 capsule and K1 polysaccharide in culture supernatants was determined in a series of in-frame nonpolar core biosynthetic mutants from Escherichia coli KT1094 (K1, R1 core lipopolysaccharide [LPS] type) for which the major core oligosaccharide structures were determined. Cell-bound K1 capsule was absent from mutants devoid of phosphoryl modifications on l-glycero-d-manno-heptose residues (HepI and HepII) of the inner-core LPS and reduced in mutants devoid of phosphoryl modification on HepII or devoid of HepIII. In contrast, in all of the mutants, K1 polysaccharide was found in culture supernatants. These results were confirmed by using a mutant with a deletion spanning from the hldD to waaQ genes of the waa gene cluster to which individual genes were reintroduced. A nuclear magnetic resonance (NMR) analysis of core LPS from HepIII-deficient mutants showed an alteration in the pattern of phosphoryl modifications. A cell extract containing both K1 capsule polysaccharide and LPS obtained from an O-antigen-deficient mutant could be resolved into K1 polysaccharide and core LPS by column chromatography only when EDTA and deoxycholate (DOC) buffer were used. These results suggest that the K1 polysaccharide remains cell associated by ionically interacting with the phosphate-negative charges of the core LPS. PMID:22522903

Evaluation of the Immunomodulatory Properties of Streptococcus suis and Group B Streptococcus Capsular Polysaccharides on the Humoral Response

PubMed Central

Calzas, Cynthia; Taillardet, Morgan; Fourati, Insaf Salem; Roy, David; Gottschalk, Marcelo; Soudeyns, Hugo; Defrance, Thierry; Segura, Mariela

2017-01-01

Streptococcus suis and group B Streptococcus (GBS) are encapsulated streptococci causing septicemia and meningitis. Antibodies (Abs) against capsular polysaccharides (CPSs) have a crucial protective role, but the structure/composition of the CPS, including the presence of sialic acid, may interfere with the generation of anti-CPS Ab responses. We investigated the features of the CPS-specific Ab response directed against S. suis serotypes 2 and 14 and GBS serotypes III and V after infection or immunization with purified native or desialylated CPSs in mice. Whereas S. suis-infected mice developed a very low/undetectable CPS-specific IgM response, significant anti-CPS IgM titers were measured in GBS-infected animals (especially for type III GBS). No isotype switching was detected in S. suis- or GBS-infected mice. While the expression of sialic acid was essential for the immunogenicity of purified GBS type III CPS, this sugar was not responsible for the inability of purified S. suis types 2, 14 and GBS type V CPSs to induce a specific Ab response. Thus, other biochemical criteria unrelated to the presence of sialic acid may be responsible for the inaptitude of the host immune system to mount an effective response against certain S. suis and GBS CPS types. PMID:28425925

Vi Capsular Polysaccharide Produced by Recombinant Salmonella enterica Serovar Paratyphi A Confers Immunoprotection against Infection by Salmonella enterica Serovar Typhi

PubMed Central

Xiong, Kun; Zhu, Chunyue; Chen, Zhijin; Zheng, Chunping; Tan, Yong; Rao, Xiancai; Cong, Yanguang

2017-01-01

Enteric fever is predominantly caused by Salmonella enterica serovar Typhi and Salmonella enterica serovar Paratyphi A, and accounts for an annual global incidence of 26.9 millions. In recent years, the rate of S. Paratyphi A infection has progressively increased. Currently licensed vaccines for typhoid fever, live Ty21a vaccine, Vi subunit vaccine, and Vi-conjugate vaccine, confer inadequate cross immunoprotection against enteric fever caused by S. Paratyphi A. Therefore, development of bivalent vaccines against enteric fever is urgently required. The immunogenic Vi capsular polysaccharide is characteristically produced in S. Typhi, but it is absent in S. Paratyphi A. We propose that engineering synthesis of Vi in S. Paratyphi A live-attenuated vaccine may expand its protection range to cover S. Typhi. In this study, we cloned the viaB locus, which contains 10 genes responsible for Vi biosynthesis, and integrated into the chromosome of S. Paratyphi A CMCC 50093. Two virulence loci, htrA and phoPQ, were subsequently deleted to achieve a Vi-producing attenuated vaccine candidate. Our data showed that, despite more than 200 passages, the viaB locus was stably maintained in the chromosome of S. Paratyphi A and produced the Vi polysaccharide. Nasal immunization of the vaccine candidate stimulated high levels of Vi-specific and S. Paratyphi A-specific antibodies in mice sera as well as total sIgA in intestinal contents, and showed significant protection against wild-type challenge of S. Paratyphi A or S. Typhi. Our study show that the Vi-producing attenuated S. Paratyphi A is a promising bivalent vaccine candidate for the prevention of enteric fever. PMID:28484685

Streptococcus suis Capsular Polysaccharide Inhibits Phagocytosis through Destabilization of Lipid Microdomains and Prevents Lactosylceramide-Dependent Recognition

PubMed Central

Houde, Mathieu; Gottschalk, Marcelo; Gagnon, Fleur; Van Calsteren, Marie-Rose

2012-01-01

Streptococcus suis type 2 is a major swine pathogen and a zoonotic agent, causing meningitis in both swine and humans. S. suis infects the host through the respiratory route, reaches the bloodstream, and persists until breaching into the central nervous system. The capsular polysaccharide (CPS) of S. suis type 2 is considered a key virulence factor of the bacteria. Though CPS allows S. suis to adhere to the membrane of cells of the immune system, it provides protection against phagocytosis. In fact, nonencapsulated mutants are easily internalized and killed by macrophages and dendritic cells. The objective of this work was to study the molecular mechanisms by which the CPS of S. suis prevents phagocytosis. By using latex beads covalently linked with purified CPS, it was shown that CPS itself was sufficient to inhibit entry of both latex beads and bystander fluorescent beads into macrophages. Upon contact with macrophages, encapsulated S. suis was shown to destabilize lipid microdomains at the cell surface, to block nitric oxide (NO) production during infection, and to prevent lactosylceramide accumulation at the phagocytic cup during infection. In contrast, the nonencapsulated mutant was easily internalized via lipid rafts, in a filipin-sensitive manner, leading to lactosylceramide recruitment and strong NO production. This is the first report to identify a role for CPS in lipid microdomain stability and to recognize an interaction between S. suis and lactosylceramide in phagocytes. PMID:22124659

Whiplash causes increased laxity of cervical capsular ligament

PubMed Central

Ivancic, Paul C.; Ito, Shigeki; Tominaga, Yasuhiro; Rubin, Wolfgang; Coe, Marcus P.; Ndu, Anthony B.; Carlson, Erik J.; Panjabi, Manohar M.

2009-01-01

Background Previous clinical studies have identified the cervical facet joint, including the capsular ligaments, as sources of pain in whiplash patients. The goal of this study was to determine whether whiplash caused increased capsular ligament laxity by applying quasi-static loading to whiplash-exposed and control capsular ligaments. Methods A total of 66 capsular ligament specimens (C2/3 to C7/T1) were prepared from 12 cervical spines (6 whiplash-exposed and 6 control). The whiplash-exposed spines had been previously rear impacted at a maximum peak T1 horizontal acceleration of 8 g. Capsular ligaments were elongated at 1 mm/s in increments of 0.05 mm until a tensile force of 5 N was achieved and subsequently returned to neutral position. Four pre-conditioning cycles were performed and data from the load phase of the fifth cycle were used for subsequent analyses. Ligament elongation was computed at tensile forces of 0, 0.25, 0.5, 0.75, 1.0, 2.5, and 5.0 N. Two factor, non-repeated measures ANOVA (P<0.05) was performed to determine significant differences in the average ligament elongation at tensile forces of 0 and 5 N between the whiplash-exposed and control groups and between spinal levels. Findings Average elongation of the whiplash-exposed capsular ligaments was significantly greater than that of the control ligaments at tensile forces of 0 and 5 N. No significant differences between spinal levels were observed. Interpretation Capsular ligament injuries, in the form of increased laxity, may be one component perpetuating chronic pain and clinical instability in whiplash patients. PMID:17959284

Therapeutic properties in Tunisian hot springs: first evidence of phenolic compounds in the cyanobacterium Leptolyngbya sp. biomass, capsular polysaccharides and releasing polysaccharides.

PubMed

Trabelsi, Lamia; Mnari, Amira; Abdel-Daim, Mohamed M; Abid-Essafi, Salwa; Aleya, Lotfi

2016-12-13

In Tunisia, the use of hot spring waters for both health and recreation is a tradition dating back to Roman times. In fact, thermal baths, usually called "Hammam" are recommended as a therapeutic and prophylactic measure against many types of illness and toxicity. While the chemical concentration of thermal water is admittedly associated with its therapeutic effects, the inclusion in spa waters of efficient bioproduct additives produced by photosynthetic microorganisms and that act against oxidative stress may comprise a significant supplementary value for thermal centers. The aim of this study was to investigate the antioxidant potential of the Tunisian thermophilic cyanobacterium Leptolyngbya sp. and to determine its phytochemical constituents and phenolic profile. BME (Biomass Methanolic Extract), CME (Capsular polysaccharides Methanolic Extract) and RME (Releasing polysaccharides Methanolic Extract) of Leptolyngbya sp. were examined for their antioxidant activities by means of DPPH, hydroxyl radical scavenging and ferrous ion chelating assays. Their total phenols, flavonoids, carotenoids, Mycosporine-like amino acids (MAAs) and vitamin C contents, as well as their phenolic profiles were also determined. BME has the highest content of phenols (139 ± 1.2 mg/g), flavonoids (34.9 ± 0.32 mg CEQ/g), carotenoids (2.03 ± 0.56 mg/g) and vitamin C (15.7 ± 1.55 mg/g), while the highest MAAs content (0.42 ± 0.03 mg/g) was observed in CME. BME presented both the highest DPPH and hydroxyl radical scavenging ability with an IC 50 of 0.07 and 0.38 mg/ml, respectively. The highest ferrous chelating capacity was detected in CME with an IC 50  = 0.59 mg/ml. Phenolic profiles revealed the presence of 25 phenolic compounds with the existence of hydroxytyrosol, oleuropein, resveratrol and pinoresinol. The study demonstrated that the cyanobacterium Leptolyngbya sp. possesses abundant natural antioxidant products which may have prophylactic and

Analysis of the ontogeny of the murine humoral response to Neisseria meningitidis B capsular polysaccharide reveals levels of complexity relevant to vaccine development.

PubMed

Colino, J; Outschoorn, I

2001-12-15

Although purified capsular polysaccharide of Neisseria meningitidis group B (CpsB) is not immunogenic at any age, CpsB on the bacterial surface elicits antibody responses late in ontogeny. Therefore, a detailed analysis of the ontogeny of the murine anti-CpsB response to N. meningitidis could determine key parameters regarding the poor immunogenicity of CpsB. The effects of bacterial dose, hyperimmunization, age, and sex on the induction of primary and secondary anti-CpsB immunoglobulin isotype profiles were studied. It was demonstrated that the timing and repetition of immunization and of the bacterial dose have a marked differential effect on the primary induction of anti-CpsB immunoglobulin isotypes and on the ability to induce anti-CpsB antibody responses after subsequent rechallenge. It is noteworthy that the ontogeny of the response is related to the appearance of natural anti-CpsB antibodies, but this is not associated with the presence of CpsB cross-reactive antigens in the microflora.

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

PubMed

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

2016-07-08

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.

Effect of polysaccharide admixtures on expression of multiple polysaccharide-degrading enzymes in Microbulbifer strain CMC-5.

PubMed

Jonnadula, RaviChand; Imran, Md; Poduval, Preethi B; Ghadi, Sanjeev C

2018-03-01

Microbulbifer strain CMC-5 produces agarase, alginate lyase, xylanase, carboxymethyl cellulase and carrageenase. The extracellular production of the above carbohydrases was investigated by growing Microbulbifer strain CMC-5 in a sea water based medium containing homologous/heterologous polysaccharides as a single substrate or as a combination of mixed assorted substrate. Presence of singular homologous polysaccharides in the growth medium induces respective carbohydrase at high levels. Any two polysaccharides in various combinations produced high level of homologous carbohydrase and low level of other heterologous carbohydrase. All five carbohydrases were consistently produced by strain CMC-5, when carboxymethyl cellulose was included as one of the substrate in dual substrate combination, or in presence of mix blends of all five polysaccharides. Interestingly, thalli of Gracilaria sp. that contain agar and cellulose predominantly in their cell wall induces only agarase expression in strain CMC-5.

Presence of B. thailandensis and B. thailandensis expressing B. pseudomallei-like capsular polysaccharide in Thailand, and their associations with serological response to B. pseudomallei.

PubMed

Hantrakun, Viriya; Thaipadungpanit, Janjira; Rongkard, Patpong; Srilohasin, Prapaporn; Amornchai, Premjit; Langla, Sayan; Mukaka, Mavuto; Chantratita, Narisara; Wuthiekanun, Vanaporn; Dance, David A B; Day, Nicholas P J; Peacock, Sharon J; Limmathurotsakul, Direk

2018-01-01

Burkholderia pseudomallei is an environmental Gram-negative bacillus and the cause of melioidosis. B. thailandensis, some strains of which express a B. pseudomallei-like capsular polysaccharide (BTCV), is also commonly found in the environment in Southeast Asia but is considered non-pathogenic. The aim of the study was to determine the distribution of B. thailandensis and its capsular variant in Thailand and investigate whether its presence is associated with a serological response to B. pseudomallei. We evaluated the presence of B. pseudomallei and B. thailandensis in 61 rice fields in Northeast (n = 21), East (n = 19) and Central (n = 21) Thailand. We found BTCV in rice fields in East and Central but not Northeast Thailand. Fourteen fields were culture positive for B. pseudomallei alone, 8 for B. thailandensis alone, 11 for both B. pseudomallei and B. thailandensis, 6 for both B. thailandensis and BTCV, and 5 for B. pseudomallei, B. thailandensis and BTCV. Serological testing using the indirect hemagglutination assay (IHA) of 96 farmers who worked in the study fields demonstrated that farmers who worked in B. pseudomallei-positive fields had higher IHA titers than those who worked in B. pseudomallei-negative fields (median 1:40 [range: <1:10-1:640] vs. <1:10 [range: <1:10-1:320], p = 0.002). In a multivariable ordered logistic regression model, IHA titers were significantly associated with the presence of B. pseudomallei (aOR = 3.7; 95% CI 1.8-7.8, p = 0.001) but were not associated with presence of B. thailandensis (p = 0.32) or BTCV (p = 0.32). One sequence type (696) was identified for the 27 BTCV isolates tested. This is the first report of BTCV in Thailand. The presence of B. pseudomallei and B. thailandensis in the same field was not uncommon. Our findings suggest that IHA positivity of healthy rice farmers in Thailand is associated with the presence of B. pseudomallei in rice fields rather than B. thailandensis or BTCV.

Measurement of the IgG2 response to Pneumococcal capsular polysaccharides may identify an antibody deficiency in individuals referred for immunological investigation.

PubMed

Parker, Antony; Irure Ventura, Juan; Sims, Dawn; Echeverría de Carlos, Ainara; Gómez de la Torre, Ricardo; Tricas Aizpún, Lourdes; Ocejo-Vinyals, J Gonzalo; López-Hoyos, Marcos; Wallis, Gregg; Harding, Stephen

2017-01-01

IgG2 is the most efficient subclass for providing protection against pneumococcal pathogens. We hypothesised that some individuals may be unable to mount an effective pneumococcal capsular polysaccharide (PCP) IgG2 response despite having a normal PCP IgG concentration (PCP IgG2 deficient). The median pre-vaccination PCP IgG2 concentration was significantly lower in individuals referred for immunological investigation compared to healthy controls (2.8 mg/L range, 95% CI 1.1-88 vs. 29.5mg/L, 95% CI 13.5-90, p = 0.0002). PCP IgG:IgG2 ratios were significantly higher for the referral population than for healthy controls suggesting the increased production of PCP specific subclasses other than IgG2. The percentage of individuals with PCP IgG2 deficiency was significantly higher in referral groups compared to controls (31% vs. 5%; p = 0.0009) and in an individual with PCP IgG2 deficiency, the balance of PCP specific IgG subclass antibodies post vaccination changed from IgG2>IgG1>IgG3>IgG4 to IgG1>IgG3>IgG2>IgG4. The median PCP IgG2 concentration in those with PCP IgG2 deficiency was significantly lower in the referral groups compared to controls (7.8 mg/L, 95% CI 1.1-12 vs. 12.7 mg/L, 95% CI 11.8-13.1; p = 0.006). The data suggests a defect in the production PCP IgG2 may be present in individuals with normal PCP IgG referred for immunological investigation.

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.

Spleen deposition of Cryptococcus neoformans capsular glucuronoxylomannan in rodents occurs in red pulp macrophages and not marginal zone macrophages expressing the C-type lectin SIGN-R1.

PubMed

De Jesus, Magdia; Park, Chae Gyu; Su, Ya; Goldman, David L; Steinman, Ralph M; Casadevall, Arturo

2008-03-01

The fate of microbial polysaccharides in host tissues is an important consideration because these compounds are often immune modulators. Splenic marginal zone macrophages that express the C-type lectin receptor SIGN-R1, take up neutral polysaccharides such as dextran and the capsular polysaccharide of Streptococcus pneumoniae. Given that the major component of Cryptococcus neoformans capsular polysaccharide, glucuronoxylomannan (GXM), localizes in the spleen when injected intravenously, we investigated whether GXM uptake was mediated by splenic macrophages expressing the SIGN-R1 receptor in mice. No significant differences in the amount and location of GXM deposition were detected in the spleens of mice treated with a SIGN-R1 blocking antibody when compared to controls. Similarly, a blocking antibody to Dectin-1, a co-receptor of -SIGN-R1, had no effects on GXM distribution within the spleen. Histological examination of spleens from mice and rats injected with FITC-Dextran and GXM revealed no significant co-localization, with Dextran and GXM being found in marginal and red pulp macrophages, respectively. Hence we conclude that GXM was not deposited in marginal zone macrophages. However, GXM deposition was found in the red pulp. These results indicate that there is a selective localization of these polysaccharides to different receptors such as SIGN-R1 for FITC dextran in marginal zone and a to-be-identified receptor selectively expressed by red pulp macrophages for GXM.

Generalized Joint Hypermobility Is Predictive of Hip Capsular Thickness.

PubMed

Devitt, Brian M; Smith, Bjorn N; Stapf, Robert; Tacey, Mark; O'Donnell, John M

2017-04-01

The pathomechanics of hip microinstability are not clearly defined but are thought to involve anatomical abnormalities, repetitive forces across the hip, and ligamentous laxity. The purpose of this study was to explore the relationship between generalized joint hypermobility (GJH) and hip capsular thickness. The hypothesis was that GJH would be predictive of a thin hip capsule. Cross-sectional study; Level of evidence, 3. A prospective study was performed on 100 consecutive patients undergoing primary hip arthroscopy for the treatment of hip pain. A Beighton test score (BTS) was obtained prior to each procedure. The maximum score was 9, and a score of ≥4 was defined as hypermobile. Capsular thickness at the level of the anterior portal, corresponding to the location of the iliofemoral ligament, was measured arthroscopically using a calibrated probe. The presence of ligamentum teres (LT) pathology was also recorded. Fifty-five women and 45 men were included in the study. The mean age was 32 years (range, 18-45 years). The median hip capsule thickness was statistically greater in men than women (12.5 and 7.5 mm, respectively). The median BTS for men was 1 compared with 4 for women ( P < .001). A statistically significant association was found between BTS and capsular thickness; a BTS of <4 is strongly predictive of having a capsular thickness of ≥10 mm, while a BTS ≥4 correlates with a capsular thickness of <10 mm. There was a statistically greater incidence of LT tears in patients with a capsular thickness of ≤7.5 mm and a BTS of ≥4 ( P < .001). Measurement of the GJH is highly predictive of hip capsular thickness. A BTS of <4 correlates significantly with a capsular thickness of ≥10 mm, while a BTS ≥4 correlates significantly with a thickness of <10 mm.

Analysis of the K1 capsule biosynthesis genes of Escherichia coli: definition of three functional regions for capsule production.

PubMed

Boulnois, G J; Roberts, I S; Hodge, R; Hardy, K R; Jann, K B; Timmis, K N

1987-06-01

Transposon and deletion analysis of the cloned K1 capsule biosynthesis genes of Escherichia coli revealed that approximately 17 kb of DNA, split into three functional regions, is required for capsule production. One block (region 1) is required for translocation of polysaccharide to the cell surface and mutations in this region result in the intracellular appearance of polymer indistinguishable on immunoelectrophoresis to that found on the surface of K1 encapsulated bacteria. This material was released from the cell by osmotic shock indicating that the polysaccharide was probably present in the periplasmic space. Insertions in a second block (region 2) completely abolished polymer production and this second region is believed to encode the enzymes for the biosynthesis and polymerisation of the K1 antigen. Addition of exogenous N-acetylneuraminic acid to one insertion mutant in this region restored its ability to express surface polymer as judged by K1 phage sensitivity. This insertion probably defines genes involved in biosynthesis of N-acetylneuraminic acid. Insertions in a third block (region 3) result in the intracellular appearance of polysaccharide with a very low electrophoretic mobility. The presence of the cloned K1 capsule biosynthesis genes on a multicopy plasmid in an E. coli K-12 strain did not increase the yields of capsular polysaccharide produced compared to the K1+ isolate from which the genes were cloned.

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

Polysaccharide production by lactic acid bacteria: from genes to industrial applications.

PubMed

Zeidan, Ahmad A; Poulsen, Vera Kuzina; Janzen, Thomas; Buldo, Patrizia; Derkx, Patrick M F; Øregaard, Gunnar; Neves, Ana Rute

2017-08-01

The ability to produce polysaccharides with diverse biological functions is widespread in bacteria. In lactic acid bacteria (LAB), production of polysaccharides has long been associated with the technological, functional and health-promoting benefits of these microorganisms. In particular, the capsular polysaccharides and exopolysaccharides have been implicated in modulation of the rheological properties of fermented products. For this reason, screening and selection of exocellular polysaccharide-producing LAB has been extensively carried out by academia and industry. To further exploit the ability of LAB to produce polysaccharides, an in-depth understanding of their biochemistry, genetics, biosynthetic pathways, regulation and structure-function relationships is mandatory. Here, we provide a critical overview of the latest advances in the field of glycosciences in LAB. Surprisingly, the understanding of the molecular processes involved in polysaccharide synthesis is lagging behind, and has not accompanied the increasing commercial value and application potential of these polymers. Seizing the natural diversity of polysaccharides for exciting new applications will require a concerted effort encompassing in-depth physiological characterization of LAB at the systems level. Combining high-throughput experimentation with computational approaches, biochemical and structural characterization of the polysaccharides and understanding of the structure-function-application relationships is essential to achieve this ambitious goal. © FEMS 2017.

Decoration of Chondroitin Polysaccharide with Threonine: Synthesis, Conformational Study, and Ice-Recrystallization Inhibition Activity.

PubMed

Laezza, Antonio; Casillo, Angela; Cosconati, Sandro; Biggs, Caroline I; Fabozzi, Antonio; Paduano, Luigi; Iadonisi, Alfonso; Novellino, Ettore; Gibson, Matthew I; Randazzo, Antonio; Corsaro, Maria M; Bedini, Emiliano

2017-08-14

Several threonine (Thr)- and alanine (Ala)-rich antifreeze glycoproteins (AFGPs) and polysaccharides act in nature as ice recrystallization inhibitors. Among them, the Thr-decorated capsular polysaccharide (CPS) from the cold-adapted Colwellia psychrerythraea 34H bacterium was recently investigated for its cryoprotectant activity. A semisynthetic mimic thereof was here prepared from microbial sourced chondroitin through a four-step strategy, involving a partial protection of the chondroitin polysaccharide as a key step for gaining an unprecedented quantitative amidation of its glucuronic acid units. In-depth NMR and computational analysis suggested a fairly linear conformation for the semisynthetic polysaccharide, for which the antifreeze activity by a quantitative ice recrystallization inhibition assay was measured. We compared the structure-activity relationships for the Thr-derivatized chondroitin and the natural Thr-decorated CPS from C. psychrerythraea.

Antibody Response Specific to the Capsular Polysaccharide Is Impaired in Streptococcus suis Serotype 2-Infected Animals

PubMed Central

Calzas, Cynthia; Lemire, Paul; Auray, Gael; Gerdts, Volker; Gottschalk, Marcelo

2014-01-01

Streptococcus suis serotype 2 is an extracellular encapsulated bacterium that causes severe septicemia and meningitis in swine and humans. Albeit crucial in the fight against encapsulated bacteria, the nature of the capsular polysaccharide (CPS)-specific antibody (Ab) response during S. suis type 2 infection is unknown. We compared for the first time the features of CPS-specific versus protein-specific Ab responses during experimental infections with live virulent S. suis type 2 in mice. The primary protein-specific Ab response was dominated by both type 1 and 2 IgG subclasses, whereas IgM titers were more modest. The secondary protein-specific Ab response showed all of the features of a memory response with faster kinetics and boosted the titers of all Ig isotypes. In contrast, the primary CPS-specific Ab response was either inexistent or had titers only slightly higher than those in noninfected animals and was essentially composed of IgM. A poor CPS-specific memory response was observed, with only a moderate boost in IgM titers and no IgG. Both protein- and CPS-specific Ab responses were Toll-like receptor 2 independent. By using S. suis type 2 strains of European or North American origin, the poor CPS-specific Ab response was demonstrated to be independent of the genotypic/phenotypic diversity of the strain within serotype 2. Finally, the CPS-specific Ab response was also impaired and lacked isotype switching in S. suis-infected pigs, the natural host of the bacterium. The better resistance of preinfected animals to reinfection with the same strain of S. suis type 2 might thus more likely be related to the development of a protein rather than CPS Ab response. PMID:25385801

Generalized Joint Hypermobility Is Predictive of Hip Capsular Thickness

PubMed Central

Devitt, Brian M.; Smith, Bjorn N.; Stapf, Robert; Tacey, Mark; O’Donnell, John M.

2017-01-01

Background: The pathomechanics of hip microinstability are not clearly defined but are thought to involve anatomical abnormalities, repetitive forces across the hip, and ligamentous laxity. Purpose/Hypothesis: The purpose of this study was to explore the relationship between generalized joint hypermobility (GJH) and hip capsular thickness. The hypothesis was that GJH would be predictive of a thin hip capsule. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A prospective study was performed on 100 consecutive patients undergoing primary hip arthroscopy for the treatment of hip pain. A Beighton test score (BTS) was obtained prior to each procedure. The maximum score was 9, and a score of ≥4 was defined as hypermobile. Capsular thickness at the level of the anterior portal, corresponding to the location of the iliofemoral ligament, was measured arthroscopically using a calibrated probe. The presence of ligamentum teres (LT) pathology was also recorded. Results: Fifty-five women and 45 men were included in the study. The mean age was 32 years (range, 18-45 years). The median hip capsule thickness was statistically greater in men than women (12.5 and 7.5 mm, respectively). The median BTS for men was 1 compared with 4 for women (P < .001). A statistically significant association was found between BTS and capsular thickness; a BTS of <4 is strongly predictive of having a capsular thickness of ≥10 mm, while a BTS ≥4 correlates with a capsular thickness of <10 mm. There was a statistically greater incidence of LT tears in patients with a capsular thickness of ≤7.5 mm and a BTS of ≥4 (P < .001). Conclusion: Measurement of the GJH is highly predictive of hip capsular thickness. A BTS of <4 correlates significantly with a capsular thickness of ≥10 mm, while a BTS ≥4 correlates significantly with a thickness of <10 mm. PMID:28451620

Key Role of Capsular Polysaccharide in the Induction of Systemic Infection and Abortion by Hypervirulent Campylobacter jejuni

PubMed Central

Sahin, Orhan; Terhorst, Samantha A.; Burrough, Eric R.; Shen, Zhangqi; Wu, Zuowei; Dai, Lei; Tang, Yizhi; Plummer, Paul J.; Ji, Ju; Yaeger, Michael J.

2017-01-01

ABSTRACT Campylobacter jejuni is a zoonotic pathogen, and a hypervirulent clone, named clone SA, has recently emerged as the predominant cause of ovine abortion in the United States. To induce abortion, orally ingested Campylobacter must translocate across the intestinal epithelium, spread systemically in the circulation, and reach the fetoplacental tissue. Bacterial factors involved in these steps are not well understood. C. jejuni is known to produce capsular polysaccharide (CPS), but the specific role that CPS plays in systemic infection and particularly abortion in animals remains to be determined. In this study, we evaluated the role of CPS in bacteremia using a mouse model and in abortion using a pregnant guinea pig model following oral challenge. Compared with C. jejuni NCTC 11168 and 81-176, a clone SA isolate (IA3902) resulted in significantly higher bacterial counts and a significantly longer duration of bacteremia in mice. The loss of capsule production via gene-specific mutagenesis in IA3902 led to the complete abolishment of bacteremia in mice and abortion in pregnant guinea pigs, while complementation of capsule expression almost fully restored these phenotypes. The capsule mutant strain was also impaired for survival in guinea pig sera and sheep blood. Sequence-based analyses revealed that clone SA possesses a unique CPS locus with a mosaic structure, which has been stably maintained in all clone SA isolates derived from various hosts and times. These findings establish CPS as a key virulence factor for the induction of systemic infection and abortion in pregnant animals and provide a viable candidate for the development of vaccines against hypervirulent C. jejuni. PMID:28373351

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

Serotyping of Streptococcus pneumoniae Based on Capsular Genes Polymorphisms

PubMed Central

Raymond, Frédéric; Boucher, Nancy; Allary, Robin; Robitaille, Lynda; Lefebvre, Brigitte; Tremblay, Cécile

2013-01-01

Streptococcus pneumoniae serotype epidemiology is essential since serotype replacement is a concern when introducing new polysaccharide-conjugate vaccines. A novel PCR-based automated microarray assay was developed to assist in the tracking of the serotypes. Autolysin, pneumolysin and eight genes located in the capsular operon were amplified using multiplex PCR. This step was followed by a tagged fluorescent primer extension step targeting serotype-specific polymorphisms. The tagged primers were then hybridized to a microarray. Results were exported to an expert system to identify capsular serotypes. The assay was validated on 166 cultured S. pneumoniae samples from 63 different serotypes as determined by the Quellung method. We show that typing only 12 polymorphisms located in the capsular operon allows the identification at the serotype level of 22 serotypes and the assignation of 24 other serotypes to a subgroup of serotypes. Overall, 126 samples (75.9%) were correctly serotyped, 14 were assigned to a member of the same serogroup, 8 rare serotypes were erroneously serotyped, and 18 gave negative serotyping results. Most of the discrepancies involved rare serotypes or serotypes that are difficult to discriminate using a DNA-based approach, for example 6A and 6B. The assay was also tested on clinical specimens including 43 cerebrospinal fluid samples from patients with meningitis and 59 nasopharyngeal aspirates from bacterial pneumonia patients. Overall, 89% of specimens positive for pneumolysin were serotyped, demonstrating that this method does not require culture to serotype clinical specimens. The assay showed no cross-reactivity for 24 relevant bacterial species found in these types of samples. The limit of detection for serotyping and S. pneumoniae detection was 100 genome equivalent per reaction. This automated assay is amenable to clinical testing and does not require any culturing of the samples. The assay will be useful for the evaluation of serotype

Separation of water-soluble polysaccharides from Cyclocarya paliurus by ultrafiltration process.

PubMed

Xie, Jian-Hua; Shen, Ming-Yue; Nie, Shao-Ping; Zhao, Qiang; Li, Chang; Xie, Ming-Yong

2014-01-30

In this study, ultrafiltration membrane process was employed to separate polysaccharides from Cyclocarya paliurus (Batal.) Iljinskaja (C. paliurus) to simulate industrial production. Meanwhile, the molecular weight distribution of C. paliurus polysaccharides was investigated by gel permeation chromatography. Four fractions were obtained and named as CPPS-A, CPPS-B, CPPS-C and CPPS-D, respectively. CPPS-A and CPPS-B contained approximately 69.5% and 12.7% of polysaccharides, whose molecular weight were in the range of 100-300 kDa and 120 kDa, respectively. CPPS-C was comprised of two polysaccharides with average molecular weight of 40 kDa and 15 kDa. Results showed that ultrafiltration resulted in the removal of parts of small molecule weight polysaccharides, the increase of proportion of high molecule weight ones and the obvious improvement of quality of products. Compared with ethanol precipitation and gel permeation chromatography techniques, ultrafiltration showed many advantages, and also provided theoretical support for industrial manufacturing of C. paliurus polysaccharides in separation. Copyright © 2013 Elsevier Ltd. All rights reserved.

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. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Differential regulation of polysaccharide-specific antibody responses to isolated polysaccharides, conjugate vaccines, and intact Gram-positive versus Gram-negative extracellular bacteria.

PubMed

Snapper, Clifford M

2016-06-24

Bacterial capsular polysaccharides are major virulence factors and are key targets in a number of licensed anti-bacterial vaccines. Their major characteristics are their large molecular weight and expression of repeating antigenic epitopes that mediate multivalent B cell receptor cross-linking. In addition, since the majority of these antigens cannot associate with MHC-II they fail to recruit CD4+ T cell help and are referred to as T cell-independent antigens. In this review I will discuss a series of studies from my laboratory that have underscored the importance of understanding polysaccharide-specific antibody responses within the context in which the PS is expressed (i.e. in isolation, as a component of conjugate vaccines, and expressed naturally by intact bacteria). We have shown that multivalent B cell receptor crosslinking, as mediated by polysaccharides, uniquely determines the qualitative response of the B cell to subsequent stimuli, but by itself is insufficient to induce antibody secretion or class switching. For these latter events to occur, second signals must act in concert with primary signals derived from the B cell receptor. The co-expression of polysaccharide and protein within intact bacteria promotes recruitment of CD4+ T cell help for the associated PS-specific IgG response, in contrast to isolated polysaccharides. Further, the particulate nature of extracellular bacteria confers properties to the polysaccharide-specific IgG response that makes it distinct immunologically from soluble conjugate vaccines. Finally, the underlying biochemical and/or structural differences that distinguish Gram-positive and Gram-negative bacteria appear to play critical roles in differentially regulating the associated polysaccharide-specific IgG responses to these groups of pathogens. These studies have a number of implications for the understanding and future design of polysaccharide-based vaccines. Published by Elsevier Ltd.

Preferential use of lambda light chains is associated with defective mouse antibody responses to the capsular polysaccharide of Neisseria meningitidis group B.

PubMed

Colino, Jesus; Outschoorn, Ingrid

2004-01-01

The capsular polysaccharide of Neisseria meningitidis group B (CpsB) is a very poor immunogen in mammals; this has been considered to be due to the induction of tolerance to cross-reactive host glycoconjugates. It has hampered the development of an effective vaccine against this meningococcal group for many years. Syngeneic populations have a similar tolerogenic background. Thus, we used the variability in ability to mount CpsB-specific immunoglobulin (Ig) responses of individuals from these populations to reveal underlying mechanisms to tolerance contributing to the poor immunogenicity of CpsB. Here we analyze by ELISA, the individual CpsB-specific Ig response of BALB/c and other syngeneic mice to immunization with intact bacteria, using the distribution of light chains as a direct indicator of the repertoire dynamics of the response. Although approximately 96% of anti-CpsB Ig bear kappa-light chains, BALB/c mouse populations were heterogeneous in the light chain composition of their individual anti-CpsB Ig responses. The proportion of kappa and lambda-light chains used for anti-CpsB Ig was a private characteristic that remained relatively constant, for each individual, through repetitive immunizations regardless of the bacterial stimuli size. Despite the prevalence of individual use of kappa-light chains, 5% of BALB/c mice showed restricted usage of lambda-light chains in their CpsB-specific Ig responses, and an additional 11% use them significantly. The preferential use of lambda-light chains in these mice was strongly associated with defective IgM, and absent or barely detectable IgG anti-CpsB responses even after repetitive bacterial immunization. We conclude that differences in the private repertoire of specific Ig also contribute to mouse unresponsiveness to CpsB.

Isolation and genetic characterization of an Actinobacillus pleuropneumoniae serovar K12:O3 strain.

PubMed

Ito, Hiroya; Matsumoto, Atsuko

2015-01-01

An atypical Actinobacillus pleuropneumoniae serovar 12 strain, termed QAS106, was isolated from a clinical case of porcine pleuropneumonia in Japan. An immunodiffusion (ID) test identified the strain as serovar 12. However, the ID test also demonstrated that strain QAS106 shared antigenic determinants with both the serovar 3 and 15 reference strains. Strain QAS106 was positive in the capsular serovar 12-specific polymerase chain reaction (PCR) assay, while the PCR toxin gene profiling and omlA PCR typing assays indicated that strain QAS106 was similar to serovar 3. The nucleotide sequence of the 16S ribosomal DNA (rDNA) of strain QAS106 was identical with that of serovars 3 and 12, but it showed 99.7% identity with that of serovar 15. Nucleotide sequence analysis revealed that genes involved in biosynthesis of the capsular polysaccharide (CPS) of strain QAS106 were identical to those of serovar 12 at the amino acid level. On the other hand, strain QAS106 would express putative proteins involved in the biosynthesis of lipopolysaccharide (LPS) O-polysaccharide (O-PS), the amino acid sequences of which were identical or nearly identical to those of serovars 3 and 15. In conclusion, strain QAS106 should be recognized as K12:O3, even though typical serovar 12 strains are K12:O12. The emergence of an atypical A. pleuropneumoniae serovar 12 strain expressing a rare combination of CPS and O-PS antigens would hamper precise serodiagnosis by the use of either CPS- or LPS-based serodiagnostic methodology alone. © 2014 The Author(s).

Antibody against Surface-Bound C5a Peptidase Is Opsonic and Initiates Macrophage Killing of Group B Streptococci

PubMed Central

Cheng, Qi; Carlson, Brian; Pillai, Sub; Eby, Ron; Edwards, Lorri; Olmsted, Stephen B.; Cleary, Patrick

2001-01-01

The capsular polysaccharides of group B streptococci (GBS) are a primary focus of vaccine development. Immunogenicity and long-lasting protection are best achieved by conjugating polysaccharides to a T-cell-dependent protein antigen. Streptococcal C5a peptidase (SCPB) is a conserved surface protein that is expressed by all streptococcal serotypes tested to date, and it is a possible carrier protein that could itself induce a protective immune response. Clearance of GBS from lungs, mucosal surfaces, or blood probably depends on the opsonophagocytic response of tissue-specific macrophages and polymorphonuclear leukocytes (PMNs). In this study, we examined the potential of antibody directed against SCPB from a serotype II strain to enhance the capacity of mouse bone marrow macrophages (from primary cultures) and human PMNs in whole blood to kill GBS in vitro. Our experiments demonstrated that Streptococcus serotypes Ia, Ib, II, III, and V, preopsonized with anti-SCPB antibody, were killed more rapidly by cultured macrophages and PMNs in whole blood than were nonopsonized GBS. The increased rate of killing was accompanied by an increased macrophage oxidative burst. Furthermore, opsonization was serotype transparent. Immunization with SCPB conjugated to capsular polysaccharide type III produced polysaccharide-specific antibodies. It is interesting that this antiserum promoted serotype-independent killing of streptococci. These data support the use of SCPB in a GBS polysaccharide conjugate vaccine. SCPB not only enhanced the immunogenicity of polysaccharide components of the vaccine, but it might also induce additional serotype-independent protective antibodies. PMID:11254587

Antibody against surface-bound C5a peptidase is opsonic and initiates macrophage killing of group B streptococci.

PubMed

Cheng, Q; Carlson, B; Pillai, S; Eby, R; Edwards, L; Olmsted, S B; Cleary, P

2001-04-01

The capsular polysaccharides of group B streptococci (GBS) are a primary focus of vaccine development. Immunogenicity and long-lasting protection are best achieved by conjugating polysaccharides to a T-cell-dependent protein antigen. Streptococcal C5a peptidase (SCPB) is a conserved surface protein that is expressed by all streptococcal serotypes tested to date, and it is a possible carrier protein that could itself induce a protective immune response. Clearance of GBS from lungs, mucosal surfaces, or blood probably depends on the opsonophagocytic response of tissue-specific macrophages and polymorphonuclear leukocytes (PMNs). In this study, we examined the potential of antibody directed against SCPB from a serotype II strain to enhance the capacity of mouse bone marrow macrophages (from primary cultures) and human PMNs in whole blood to kill GBS in vitro. Our experiments demonstrated that Streptococcus serotypes Ia, Ib, II, III, and V, preopsonized with anti-SCPB antibody, were killed more rapidly by cultured macrophages and PMNs in whole blood than were nonopsonized GBS. The increased rate of killing was accompanied by an increased macrophage oxidative burst. Furthermore, opsonization was serotype transparent. Immunization with SCPB conjugated to capsular polysaccharide type III produced polysaccharide-specific antibodies. It is interesting that this antiserum promoted serotype-independent killing of streptococci. These data support the use of SCPB in a GBS polysaccharide conjugate vaccine. SCPB not only enhanced the immunogenicity of polysaccharide components of the vaccine, but it might also induce additional serotype-independent protective antibodies.

Whole-Genome-Sequencing characterization of bloodstream infection-causing hypervirulent Klebsiella pneumoniae of capsular serotype K2 and ST374.

PubMed

Wang, Xiaoli; Xie, Yingzhou; Li, Gang; Liu, Jialin; Li, Xiaobin; Tian, Lijun; Sun, Jingyong; Ou, Hong-Yu; Qu, Hongping

2018-01-01

Hypervirulent K. pneumoniae variants (hvKP) have been increasingly reported worldwide, causing metastasis of severe infections such as liver abscesses and bacteremia. The capsular serotype K2 hvKP strains show diverse multi-locus sequence types (MLSTs), but with limited genetics and virulence information. In this study, we report a hypermucoviscous K. pneumoniae strain, RJF293, isolated from a human bloodstream sample in a Chinese hospital. It caused a metastatic infection and fatal septic shock in a critical patient. The microbiological features and genetic background were investigated with multiple approaches. The Strain RJF293 was determined to be multilocis sequence type (ST) 374 and serotype K2, displayed a median lethal dose (LD50) of 1.5 × 10 2 CFU in BALB/c mice and was as virulent as the ST23 K1 serotype hvKP strain NTUH-K2044 in a mouse lethality assay. Whole genome sequencing revealed that the RJF293 genome codes for 32 putative virulence factors and exhibits a unique presence/absence pattern in comparison to the other 105 completely sequenced K. pneumoniae genomes. Whole genome SNP-based phylogenetic analysis revealed that strain RJF293 formed a single clade, distant from those containing either ST66 or ST86 hvKP. Compared to the other sequenced hvKP chromosomes, RJF293 contains several strain-variable regions, including one prophage, one ICEKp1 family integrative and conjugative element and six large genomic islands. The sequencing of the first complete genome of an ST374 K2 hvKP clinical strain should reinforce our understanding of the epidemiology and virulence mechanisms of this bloodstream infection-causing hvKP with clinical significance.

Whole-Genome-Sequencing characterization of bloodstream infection-causing hypervirulent Klebsiella pneumoniae of capsular serotype K2 and ST374

PubMed Central

Wang, Xiaoli; Xie, Yingzhou; Li, Gang; Liu, Jialin; Li, Xiaobin; Tian, Lijun; Sun, Jingyong; Qu, Hongping

2018-01-01

ABSTRACT Hypervirulent K. pneumoniae variants (hvKP) have been increasingly reported worldwide, causing metastasis of severe infections such as liver abscesses and bacteremia. The capsular serotype K2 hvKP strains show diverse multi-locus sequence types (MLSTs), but with limited genetics and virulence information. In this study, we report a hypermucoviscous K. pneumoniae strain, RJF293, isolated from a human bloodstream sample in a Chinese hospital. It caused a metastatic infection and fatal septic shock in a critical patient. The microbiological features and genetic background were investigated with multiple approaches. The Strain RJF293 was determined to be multilocis sequence type (ST) 374 and serotype K2, displayed a median lethal dose (LD50) of 1.5 × 102 CFU in BALB/c mice and was as virulent as the ST23 K1 serotype hvKP strain NTUH-K2044 in a mouse lethality assay. Whole genome sequencing revealed that the RJF293 genome codes for 32 putative virulence factors and exhibits a unique presence/absence pattern in comparison to the other 105 completely sequenced K. pneumoniae genomes. Whole genome SNP-based phylogenetic analysis revealed that strain RJF293 formed a single clade, distant from those containing either ST66 or ST86 hvKP. Compared to the other sequenced hvKP chromosomes, RJF293 contains several strain-variable regions, including one prophage, one ICEKp1 family integrative and conjugative element and six large genomic islands. The sequencing of the first complete genome of an ST374 K2 hvKP clinical strain should reinforce our understanding of the epidemiology and virulence mechanisms of this bloodstream infection-causing hvKP with clinical significance. PMID:29338592

Understanding Microbial Sensing in Inflammatory Bowel Disease Using Click Chemistry

DTIC Science & Technology

2016-10-01

lipopolysaccharide, capsular polysaccharide , and peptidoglycan simultaneously in live anaerobic commensal bacteria. This technology enabled us to track the...endotoxin, capsular polysaccharide , inflammatory bowel disease,microbiome microbiota, carbohydrate chemistry, fluorescent microscopy, 2-photon...lipopolysaccharide, endotoxin, capsular polysaccharide , inflammatory bowel disease, microbiome, microbiota, carbohydrate chemistry, fluorescent microscopy

Understanding Mircrobial Sensing in Inflammatory Bowel Disease Using Click Chemistry

DTIC Science & Technology

2016-10-01

limitation, we have developed an expanded metabolic labeling approach that chemically tags lipopolysaccharide, capsular polysaccharide , and peptidoglycan...click-chemistry, bacterial cell wall, bacterial outer membrane, peptidoglycan, lipopolysaccharide, endotoxin, capsular polysaccharide , inflammatory...bacterial outer membrane, peptidoglycan, lipopolysaccharide, endotoxin, capsular polysaccharide , inflammatory bowel disease, microbiome, microbiota

A Predicted Mannoprotein Participates in Cryptococcus gattii Capsular Structure

PubMed Central

Reuwsaat, Julia Catarina Vieira; Motta, Heryk; Garcia, Ane Wichine Acosta; Vasconcelos, Carolina Bettker; Marques, Bárbara Machado; Oliveira, Natália Kronbauer; Rodrigues, Jéssica; Ferrareze, Patrícia Aline Gröhns; Frases, Susana; Barcellos, Vanessa Abreu; Squizani, Eamim Daidrê; Horta, Jorge André; Schrank, Augusto; Staats, Charley Christian; Vainstein, Marilene Henning

2018-01-01

ABSTRACT The yeast-like pathogen Cryptococcus gattii is an etiological agent of cryptococcosis. The major cryptococcal virulence factor is the polysaccharide capsule, which is composed of glucuronoxylomannan (GXM), galactoxylomannan (GalXM), and mannoproteins (MPs). The GXM and GalXM polysaccharides have been extensively characterized; however, there is little information about the role of mannoproteins in capsule assembly and their participation in yeast pathogenicity. The present study characterized the function of a predicted mannoprotein from C. gattii, designated Krp1. Loss-of-function and gain-of-function mutants were generated, and phenotypes associated with the capsular architecture were evaluated. The null mutant cells were more sensitive to a cell wall stressor that disrupts beta-glucan synthesis. Also, these cells displayed increased GXM release to the culture supernatant than the wild-type strain did. The loss of Krp1 influenced cell-associated cryptococcal polysaccharide thickness and phagocytosis by J774.A1 macrophages in the early hours of interaction, but no difference in virulence in a murine model of cryptococcosis was observed. In addition, recombinant Krp1 was antigenic and differentially recognized by serum from an individual with cryptococcosis, but not with serum from an individual with candidiasis. Taken together, these results indicate that C. gattii Krp1 is important for the cell wall structure, thereby influencing capsule assembly, but is not essential for virulence in vivo. IMPORTANCE Cryptococcus gattii has the ability to escape from the host’s immune system through poorly understood mechanisms and can lead to the death of healthy individuals. The role of mannoproteins in C. gattii pathogenicity is not completely understood. The present work characterized a protein, Kpr1, that is essential for the maintenance of C. gattii main virulence factor, the polysaccharide capsule. Our data contribute to the understanding of the role of Kpr

Mobile contingency locus controlling Escherichia coli K1 polysialic acid capsule acetylation.

PubMed

Vimr, Eric R; Steenbergen, Susan M

2006-05-01

Escherichia coli K1 is part of a reservoir of adherent, invasive facultative pathogens responsible for a wide range of human and animal disease including sepsis, meningitis, urinary tract infection and inflammatory bowel syndrome. A prominent virulence factor in these diseases is the polysialic acid capsular polysaccharide (K1 antigen), which is encoded by the kps/neu accretion domain inserted near pheV at 67 map units. Some E. coli K1 strains undergo form (phase) variation involving loss or gain of O-acetyl esters at carbon positions 7 or 9 of the individual sialic acid residues of the polysialic acid chains. Acetylation is catalysed by the receptor-modifying acetyl coenzyme-A-dependent O-acetyltransferase encoded by neuO, a phase variable locus mapping near the integrase gene of the K1-specific prophage, CUS-3, which is inserted in argW at 53.1 map units. As the first E. coli contingency locus shown to operate by a translational switch, further investigation of neuO should provide a better understanding of the invasive K1 pathotype. Minimal estimates of morbidity and economic costs associated with human infections caused by extraintestinal pathogenic E. coli strains such as K1 indicate at least 6.5 million cases with attendant medical costs exceeding 2.5 billion US dollars annually in the United States alone.

Therapeutic Application of Phage Capsule Depolymerases against K1, K5, and K30 Capsulated E. coli in Mice.

PubMed

Lin, Han; Paff, Matthew L; Molineux, Ian J; Bull, James J

2017-01-01

Capsule depolymerase enzymes offer a promising class of new antibiotics. In vivo studies are encouraging but it is unclear how well this type of phage product will generalize in therapeutics, or whether different depolymerases against the same capsule function similarly. Here, in vivo efficacy was tested using cloned bacteriophage depolymerases against Escherichia coli strains with three different capsule types: K1, K5, and K30. When treating infections with the cognate capsule type in a mouse thigh model, the previously studied K1E depolymerase rescued poorly, whereas K1F, K1H, K5, and K30 depolymerases rescued well. K30 gp41 was identified as the catalytically active protein. In contrast to the in vivo studies, K1E enzyme actively degraded K1 capsule polysaccharide in vitro and sensitized K1 bacteria to serum killing. The only in vitro correlate of poor K1E performance in vivo was that the purified enzyme did not form the expected trimer. K1E appeared as an 18-mer which might limit its in vivo distribution. Overall, depolymerases were easily identified, cloned from phage genomes, and as purified proteins they proved generally effective.

The Staphylococcus aureus polysaccharide capsule and Efb-dependent fibrinogen shield act in concert to protect against phagocytosis

PubMed Central

Kuipers, Annemarie; Stapels, Daphne A. C.; Weerwind, Lleroy T.; Ko, Ya-Ping; Ruyken, Maartje; Lee, Jean C.; van Kessel, Kok P. M.

2016-01-01

Staphylococcus aureus has developed many mechanisms to escape from human immune responses. To resist phagocytic clearance, S. aureus expresses a polysaccharide capsule, which effectively masks the bacterial surface and surface-associated proteins, such as opsonins, from recognition by phagocytic cells. Additionally, secretion of the extracellular fibrinogen binding protein (Efb) potently blocks phagocytic uptake of the pathogen. Efb creates a fibrinogen shield surrounding the bacteria by simultaneously binding complement C3b and fibrinogen at the bacterial surface. By means of neutrophil phagocytosis assays with fluorescently labelled encapsulated serotype 5 (CP5) and serotype 8 (CP8) strains we compare the immune-modulating function of these shielding mechanisms. The data indicate that, in highly encapsulated S. aureus strains, the polysaccharide capsule is able to prevent phagocytic uptake at plasma concentrations <10 %, but loses its protective ability at higher concentrations of plasma. Interestingly, Efb shows a strong inhibitory effect on both capsule-negative and encapsulated strains at all tested plasma concentrations. Furthermore, the results suggest that both shielding mechanisms can exist simultaneously and collaborate to provide optimal protection against phagocytosis at a broad range of plasma concentrations. As opsonizing antibodies will be shielded from recognition by either mechanism, incorporating both capsular polysaccharides and Efb in future vaccines could be of great importance. PMID:27112346

The Staphylococcus aureus polysaccharide capsule and Efb-dependent fibrinogen shield act in concert to protect against phagocytosis.

PubMed

Kuipers, Annemarie; Stapels, Daphne A C; Weerwind, Lleroy T; Ko, Ya-Ping; Ruyken, Maartje; Lee, Jean C; van Kessel, Kok P M; Rooijakkers, Suzan H M

2016-07-01

Staphylococcus aureus has developed many mechanisms to escape from human immune responses. To resist phagocytic clearance, S. aureus expresses a polysaccharide capsule, which effectively masks the bacterial surface and surface-associated proteins, such as opsonins, from recognition by phagocytic cells. Additionally, secretion of the extracellular fibrinogen binding protein (Efb) potently blocks phagocytic uptake of the pathogen. Efb creates a fibrinogen shield surrounding the bacteria by simultaneously binding complement C3b and fibrinogen at the bacterial surface. By means of neutrophil phagocytosis assays with fluorescently labelled encapsulated serotype 5 (CP5) and serotype 8 (CP8) strains we compare the immune-modulating function of these shielding mechanisms. The data indicate that, in highly encapsulated S. aureus strains, the polysaccharide capsule is able to prevent phagocytic uptake at plasma concentrations <10 %, but loses its protective ability at higher concentrations of plasma. Interestingly, Efb shows a strong inhibitory effect on both capsule-negative and encapsulated strains at all tested plasma concentrations. Furthermore, the results suggest that both shielding mechanisms can exist simultaneously and collaborate to provide optimal protection against phagocytosis at a broad range of plasma concentrations. As opsonizing antibodies will be shielded from recognition by either mechanism, incorporating both capsular polysaccharides and Efb in future vaccines could be of great importance.

Rapid preparation of functional polysaccharides from Pyropia yezoensis by microwave-assistant rapid enzyme digest system.

PubMed

Lee, Ji-Hyeok; Kim, Hyung-Ho; Ko, Ju-Young; Jang, Jun-Ho; Kim, Gwang-Hoon; Lee, Jung-Suck; Nah, Jae-Woon; Jeon, You-Jin

2016-11-20

This study describes a simple preparation of functional polysaccharides from Pyropia yezoensis using a microwave-assistant rapid enzyme digest system (MAREDS) with various carbohydrases, and evaluates their antioxidative effects. Polysaccharide hydrolysates were prepared using MAREDS under different hydrolytic conditions of the carbohydrases and microwave powers. Polysaccharides less than 10kDa (Low molecular weight polysaccharides, LMWP, ≤10kDa) were efficiently obtained using an ultrafiltration (molecular weight cut-off of 10kDa). MAREDS increases AMG activation via an increased degree of hydrolysis; the best AMG hydrolysate was prepared using a 10:1 ratio of substrate to enzyme for 2h in MAREDS with 400W. LMWP consisted of galactose (27.3%), glucose (64.5%), and mannose (8.3%) from the AMG hydrolysate had stronger antioxidant effects than the high molecular weight polysaccharides (>10kDa). We rapidly prepared functional LMWPs by using MAREDS with carbohydrases, and suggest that LMWP might be potentially a valuable algal polysaccharide antioxidant. Copyright © 2016 Elsevier Ltd. All rights reserved.

Determination of free polysaccharide in Vi glycoconjugate vaccine against typhoid fever.

PubMed

Giannelli, C; Cappelletti, E; Di Benedetto, R; Pippi, F; Arcuri, M; Di Cioccio, V; Martin, L B; Saul, A; Micoli, F

2017-05-30

Glycoconjugate vaccines based on the Vi capsular polysaccharide directed against Salmonella enterica serovar Typhi are licensed or in development against typhoid fever, an important cause of morbidity and mortality in developing countries. Quantification of free polysaccharide in conjugate vaccines is an important quality control for release, to monitor vaccine stability and to ensure appropriate immune response. However, we found that existing separation methods based on size are not appropriate as free Vi non-specifically binds to unconjugated and conjugated protein. We developed a method based on free Vi separation by Capto Adhere resin and quantification by HPAEC-PAD. The method has been tested for conjugates of Vi derived from Citrobacter freundii with different carrier proteins such as CRM 197 , Tetanus Toxoid and Diphtheria Toxoid. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Immunoregulatory activities of polysaccharides from mung bean.

PubMed

Yao, Yang; Zhu, Yingying; Ren, Guixing

2016-03-30

Ultrasonic treatment was performed on water-extractable polysaccharides from the seed of mung beans. Purified by anion-exchange and gel filtration chromatography, MWP-1' and MWP-2' were obtained. Average molecular weights (Mws) of MWP-1' and MWP-2' were 68.4 kDa, and 52.4 kDa, respectively. Monosaccharides components analysis indicated that MWP-1' was composed of Rha, Ara, Man and Gal in a molar percent of 0.4:2.6:5.3:0.7. MWP-2' was composed of Ara, Man, Gal and Glc in a molar percent of 0.5:1.4:2.1:0.4. In vitro study showed that both polysaccharides samples were able to stimulate the production of secretory molecules (NO, TNF-α and IL-6) of RAW264.7 murine macrophages in a dosage dependent manner. MWP-2' seemed to be the most potent and induced significantly higher the NO production. These findings suggest that the ultrasonic treatment polysaccharides isolated in our study have immune potentiation effects on macrophages. Copyright © 2015 Elsevier Ltd. All rights reserved.

Capsular Polysaccharide is a Main Component of Mycoplasma ovipneumoniae in the Pathogen-Induced Toll-Like Receptor-Mediated Inflammatory Responses in Sheep Airway Epithelial Cells

PubMed Central

Jiang, Zhongjia; Song, Fuyang; Li, Yanan; Xue, Di; Deng, Guangcun; Li, Min

2017-01-01

Mycoplasma ovipneumoniae (M. ovipneumoniae) is characterized as an etiological agent of primary atypical pneumonia that specifically infects sheep and goat. In an attempt to better understand the pathogen-host interaction between the invading M. ovipneumoniae and airway epithelial cells, we investigated the host inflammatory responses against capsular polysaccharide (designated as CPS) of M. ovipneumoniae using sheep bronchial epithelial cells cultured in an air-liquid interface (ALI) model. Results showed that CPS derived from M. ovipneumoniae could activate toll-like receptor- (TLR-) mediated inflammatory responses, along with an elevated expression of nuclear factor kappa B (NF-κB), activator protein-1 (AP-1), and interferon regulatory factor 3 (IRF3) as well as various inflammatory-associated mediators, representatively including proinflammatory cytokines, such as IL1β, TNFα, and IL8, and anti-inflammatory cytokines such as IL10 and TGFβ of TLR signaling cascade. Mechanistically, the CPS-induced inflammation was TLR initiated and was mediated by activations of both MyD88-dependent and MyD88-independent signaling pathways. Of importance, a blockage of CPS with specific antibody led a significant reduction of M. ovipneumoniae-induced inflammatory responses in sheep bronchial epithelial cells. These results suggested that CPS is a key virulent component of M. ovipneumoniae, which may play a crucial role in the inflammatory response induced by M. ovipneumoniae infections. PMID:28553017

Induction of tumor necrosis factor alpha by the group- and type-specific polysaccharides from type III group B streptococci.

PubMed Central

Mancuso, G; Tomasello, F; von Hunolstein, C; Orefici, G; Teti, G

1994-01-01

Previous studies suggested that circulating tumor necrosis factor alpha (TNF-alpha) may have a pathophysiologic role in experimental neonatal sepsis induced by group B streptococci (GBS). This study was undertaken to investigate the ability of the type III and group-specific polysaccharides of GBS to induce TNF-alpha production and TNF-alpha-dependent lethality in neonatal rats. The cytokine was detected in plasma samples by the L929 cytotoxicity assay. Intracardiac injections of either polysaccharide induced dose-dependent, transient elevations in plasma TNF-alpha levels that returned to baseline values after 5 h. The group-specific antigen induced significantly higher mean peak TNF-alpha levels than the type III antigen (125 +/- 47 versus 44 +/- 15 U/ml with 70 mg/kg of body weight). Glycogen (70 mg/kg), used as a negative control, did not induce TNF-alpha. The lipopolysaccharide-neutralizing agent polymyxin B did not decrease TNF-alpha levels induced by either polysaccharide, ruling out contamination with endotoxin as a possible cause of TNF-alpha induction. Fifty percent lethal doses of the type III and group-specific antigens given as intracardiac injections were 105 and 16 mg/kg, respectively. Salmonella endotoxin, used as a positive control, had a 50% lethal dose of 0.1 mg/kg. The lethal activities of GBS polysaccharides, as well as endotoxin, were completely prevented by pretreatment of neonatal rats with the respective specific antibodies or anti-murine TNF-alpha serum. To assess the relative importance of the type-specific substance in TNF-alpha induction by whole bacteria, two unrelated GBS transposon mutants devoid of only the type-specific capsular polysaccharide (COH1-13 and COH31-15) were employed. Each of the heat-killed unencapsulated mutants was able to produce plasma TNF-alpha level elevations or TNF-alpha-dependent lethality but was significantly less efficient in these activities than the corresponding encapsulated wild-type strain. These data

Molecular analysis of the genes involved in the biosynthesis of serotype specific polysaccharide in the novel serotype k strains of Streptococcus mutans.

PubMed

Nomura, R; Nakano, K; Ooshima, T

2005-10-01

We previously reported the new serotype k of Streptococcus mutans, which, compared to serotypes c, e, and f, features a drastic reduction in the length of the glucose side chain linked to the rhamnose backbone of the serotype specific polysaccharide. The 5' region of the rgpF gene of serotype k strains contains a distinctive nucleotide sequence, which suggests that an alteration of the rgpF gene in serotype k strains may explain the shortened glucose side chain. However, in the present study, expression of the rgpF gene of MT8148 (serotype c) in serotype k isolates was not found to lead to serotype conversion. Furthermore, mRNA expression of rgpE, known to be associated with glucose side chain formation, was not detected in any of the tested serotype k isolates with an RT-PCR method. The nucleotide alignment of all genes known to be involved in the biosynthesis of serotype specific polysaccharide in serotype k strains was shown to be quite similar to that of serotype c strains, as compared to serotype e and f strains, especially in the region downstream of rgpF. Our results indicate that the common characteristics of serotype k isolates may be caused by a lack of expression of the gene involved in glucose side chain formation.

Causes of hepatic capsular retraction: a pictorial essay.

PubMed

Tan, Gary Xia Vern; Miranda, Rhian; Sutherland, Tom

2016-12-01

Hepatic capsular retraction refers to the loss of the normal convex hepatic contour, with the formation of an area of flattening or concavity. This can result from myriad causes, including intrinsic hepatic conditions such as cirrhosis, biliary obstruction, benign tumours, malignancy and infections, as well as extrahepatic causes such as trauma. This article aims to provide familiarity with this wide spectrum of conditions, including mimics of hepatic capsular retraction, by highlighting the anatomic, pathologic and imaging features that help distinguish these entities from one another. • Hepatic capsular retraction can occur due to various intrinsic or extrinsic hepatic causes. • Hepatic capsular retraction is observed in both benign and malignant conditions. • Recognising associated imaging features can help elicit causes of hepatic capsular retraction.

Escherichia coli K1-specific bacteriophage CUS-3 distribution and function in phase-variable capsular polysialic acid O acetylation.

PubMed

King, Michael R; Vimr, Ross P; Steenbergen, Susan M; Spanjaard, Lodewijk; Plunkett, Guy; Blattner, Frederick R; Vimr, Eric R

2007-09-01

Escherichia coli K1 is the leading cause of human neonatal sepsis and meningitis and is important in other clinical syndromes of both humans and domestic animals; in this strain the polysialic acid capsule (K1 antigen) functions by inhibiting innate immunity. Recent discovery of the phase-variable capsular O acetylation mechanism indicated that the O-acetyltransferase gene, neuO, is carried on a putative K1-specific prophage designated CUS-3 (E. L. Deszo, S. M. Steenbergen, D. I. Freedberg, and E. R. Vimr, Proc. Natl. Acad. Sci. USA 102:5564-5569, 2005). Here we describe the isolation and characterization of a CUS-3 derivative (CUS-3a), demonstrating its morphology, lysogenization of a sensitive host, and the distribution of CUS-3 among a collection of 111 different K1 strains. The 40,207-bp CUS-3 genome was annotated from the strain RS218 genomic DNA sequence, indicating that most of the 63 phage open reading frames have their closest homologues in one of seven different lambdoid phages. Translational fusion of a reporter lacZ fragment to the hypervariable poly-Psi domain facilitated measurement of phase variation frequencies, indicating no significant differences between switch rates or effects on rates of the methyl-directed mismatch repair system. PCR analysis of poly-Psi domain length indicated preferential loss or gain of single 5'-AAGACTC-3' nucleotide repeats. Analysis of a K1 strain previously reported as "locked on" indicated a poly-Psi region with the least number of heptad repeats compatible with in-frame neuO expression. The combined results establish CUS-3 as an active mobile contingency locus in E. coli K1, indicating its capacity to mediate population-wide capsule variation.

Arthroscopic capsular plication for microtraumatic anterior shoulder instability in overhead athletes.

PubMed

Jones, Kristofer J; Kahlenberg, Cynthia A; Dodson, Christopher C; Nam, Denis; Williams, Riley J; Altchek, David W

2012-09-01

Extreme loading conditions at the glenohumeral joint during overhead athletic activities can result in both soft tissue and osseous adaptative changes at the shoulder. Subtle alterations in the stabilizing structures may lead to anterior instability and debilitating shoulder pain with subsequent inability to participate in athletics. There is currently a paucity of data documenting clinical outcomes after arthroscopic capsular plication in overhead athletes who demonstrate objective findings of pain and anterior instability on physical examination. To evaluate outcomes after arthroscopic capsular plication for anterior instability in overhead athletes with an emphasis on postoperative range of motion, postoperative shoulder function, and return to sport. Case series; Level of evidence, 4. The authors identified 20 overhead athletes with debilitating shoulder pain and a failed trial of nonoperative management who underwent arthroscopic capsular plication (12 suture plication, 8 suture anchor plication) for anterior instability related to isolated capsular redundancy. Patients were evaluated with the Single Assessment Numerical Evaluation (SANE) and Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow Score, and they were interviewed to determine the rate of return to athletic activity. Failures of treatment included patients who demonstrated debilitating pain that precluded return to sport. At a mean follow-up of 3.6 years (range, 2.0-5.5 years), 18 (90%) patients returned to overhead sports, with 17 (85%) at their preinjury level. The mean (SD) SANE score was 86 (17.5%; range, 30%-100%), and the mean (SD) KJOC score was 82 (18.2; range, 28-100). When compared with the contralateral extremity, there were no significant differences in glenohumeral range of motion. Two patients with associated rotator cuff injury experienced persistent pain with overhead activity and were unable to return to sport, representing a 10% failure rate. Arthroscopic capsular plication

Granulocyte colony-stimulating factor enhances protection by anti-K1 capsular IgM antibody in murine Escherichia coli sepsis.

PubMed

Hustinx, W; Benaissa-Trouw, B; Van Kessel, K; Kuenen, J; Tavares, L; Kraaijeveld, K; Verhoef, J; Hoepelman, A

1997-12-01

Combined prophylactic treatment with recombinant murine granulocyte colony-stimulating factor (G-CSF) and a suboptimal dose of anti-K1 capsular IgM monoclonal antibody (MAb) significantly enhanced survival in an experimental mouse Escherichia coli O7:K1 peritonitis model compared with untreated animals (67% vs. 11% survival; P < 0.001) and with either treatment alone (67 vs. 29% and 27% survival, respectively; P < 0.01), which suggests synergism between these agents. Enhanced survival by combined treatment was associated with increased neutrophil counts in blood and peritoneal lavage fluid, lower systemic and higher levels of local tumour necrosis factor (TNF) and lower bacterial counts in blood cultures. Mouse neutrophils treated with G-CSF but not infected with E. coli showed enhanced phagocytic and respiratory burst capacity, down-regulation of L-selectin receptors and enhanced expression of Fc RII-III receptors but not of complement receptors.

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

USDA-ARS?s Scientific Manuscript database

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...

Escherichia coli K1-Specific Bacteriophage CUS-3 Distribution and Function in Phase-Variable Capsular Polysialic Acid O Acetylation▿ †

PubMed Central

King, Michael R.; Vimr, Ross P.; Steenbergen, Susan M.; Spanjaard, Lodewijk; Plunkett, Guy; Blattner, Frederick R.; Vimr, Eric R.

2007-01-01

Escherichia coli K1 is the leading cause of human neonatal sepsis and meningitis and is important in other clinical syndromes of both humans and domestic animals; in this strain the polysialic acid capsule (K1 antigen) functions by inhibiting innate immunity. Recent discovery of the phase-variable capsular O acetylation mechanism indicated that the O-acetyltransferase gene, neuO, is carried on a putative K1-specific prophage designated CUS-3 (E. L. Deszo, S. M. Steenbergen, D. I. Freedberg, and E. R. Vimr, Proc. Natl. Acad. Sci. USA 102:5564-5569, 2005). Here we describe the isolation and characterization of a CUS-3 derivative (CUS-3a), demonstrating its morphology, lysogenization of a sensitive host, and the distribution of CUS-3 among a collection of 111 different K1 strains. The 40,207-bp CUS-3 genome was annotated from the strain RS218 genomic DNA sequence, indicating that most of the 63 phage open reading frames have their closest homologues in one of seven different lambdoid phages. Translational fusion of a reporter lacZ fragment to the hypervariable poly-Ψ domain facilitated measurement of phase variation frequencies, indicating no significant differences between switch rates or effects on rates of the methyl-directed mismatch repair system. PCR analysis of poly-Ψ domain length indicated preferential loss or gain of single 5′-AAGACTC-3′ nucleotide repeats. Analysis of a K1 strain previously reported as “locked on” indicated a poly-Ψ region with the least number of heptad repeats compatible with in-frame neuO expression. The combined results establish CUS-3 as an active mobile contingency locus in E. coli K1, indicating its capacity to mediate population-wide capsule variation. PMID:17601779

Efficacy of hemostatic matrix and microporous polysaccharide hemospheres.

PubMed

Lewis, Kevin M; Atlee, Holly; Mannone, Angela; Lin, Lawrence; Goppelt, Andreas

2015-02-01

Microporous Polysaccharide Hemospheres (MPH) are a new plant-derived polysaccharide powder hemostat. Previous studies investigated MPH as a replacement to nonflowable hemostatic agents of different application techniques (e.g., oxidized cellulose, collagen); therefore, the purpose of this study was to determine if MPH is a surrogate for flowable hemostatic agents of similar handling and application techniques, specifically a flowable thrombin-gelatin hemostatic matrix. Hemostatic efficacy was compared using a heparinized porcine abrasion model mimicking a capsular tear of a parenchymal organ. MPH (ARISTA, 1 g) and hemostatic matrix (Floseal, 1 mL) were applied, according to a randomized scheme, to paired hepatic abrasions (40 lesions per group). Hemostatic success, control of bleeding, and blood loss were assessed 2, 5, and 10 min after treatment. Hemostatic success and control of bleeding were analyzed using odds ratios and blood loss using mean differences. Hemostatic matrix provided superior hemostatic success relative to MPH at 5 (odds ratio: 0.035, 95% confidence interval: 0.004-0.278) and 10 min (0.032, 0.007-0.150), provided superior control of bleeding at 5 (0.006, <0.001-0.037) and 10 min (0.009, 0.001-0.051), and had significantly less blood loss at 5 (mean difference: 0.3118 mL/min, 95% confidence interval: 0.0939-0.5296) and 10 min (0.5025, 0.2489-0.7561). These findings corroborate other MPH investigations regarding its low-level efficacy and suggest that MPH is not an appropriate surrogate for hemostatic matrix despite similar application techniques. The lack of a procoagulant within MPH may likely be the reason for its lower efficacy and need for multiple applications. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

An IgaA/UmoB Family Protein from Serratia marcescens Regulates Motility, Capsular Polysaccharide Biosynthesis, and Secondary Metabolite Production.

PubMed

Stella, Nicholas A; Brothers, Kimberly M; Callaghan, Jake D; Passerini, Angelina M; Sigindere, Cihad; Hill, Preston J; Liu, Xinyu; Wozniak, Daniel J; Shanks, Robert M Q

2018-03-15

Secondary metabolites are an important source of pharmaceuticals and key modulators of microbe-microbe interactions. The bacterium Serratia marcescens is part of the Enterobacteriaceae family of eubacteria and produces a number of biologically active secondary metabolites. In this study, we screened for novel regulators of secondary metabolites synthesized by a clinical isolate of S. marcescens and found mutations in a gene for an uncharacterized UmoB/IgaA family member here named gumB Mutation of gumB conferred a severe loss of the secondary metabolites prodigiosin and serratamolide. The gumB mutation conferred pleiotropic phenotypes, including altered biofilm formation, highly increased capsular polysaccharide production, and loss of swimming and swarming motility. These phenotypes corresponded to transcriptional changes in fimA , wecA , and flhD Unlike other UmoB/IgaA family members, gumB was found to be not essential for growth in S. marcescens , yet igaA from Salmonella enterica , yrfF from Escherichia coli , and an uncharacterized predicted ortholog from Klebsiella pneumoniae complemented the gumB mutant secondary metabolite defects, suggesting highly conserved function. These data support the idea that UmoB/IgaA family proteins are functionally conserved and extend the known regulatory influence of UmoB/IgaA family proteins to the control of competition-associated secondary metabolites and biofilm formation. IMPORTANCE IgaA/UmoB family proteins are found in members of the Enterobacteriaceae family of bacteria, which are of environmental and public health importance. IgaA/UmoB family proteins are thought to be inner membrane proteins that report extracellular stresses to intracellular signaling pathways that respond to environmental challenge. This study introduces a new member of the IgaA/UmoB family and demonstrates a high degree of functional similarity between IgaA/UmoB family proteins. Moreover, this study extends the phenomena controlled by Iga

The ESX-5 System of Pathogenic Mycobacteria Is Involved In Capsule Integrity and Virulence through Its Substrate PPE10

PubMed Central

Ates, Louis S.; van der Woude, Aniek D.; Bestebroer, Jovanka; van Stempvoort, Gunny; Musters, René J. P.; Garcia-Vallejo, Juan J.; Picavet, Daisy I.; van de Weerd, Robert; Maletta, Massimiliano; Kuijl, Coenraad P.; van der Wel, Nicole N.; Bitter, Wilbert

2016-01-01

Mycobacteria produce a capsule layer, which consists of glycan-like polysaccharides and a number of specific proteins. In this study, we show that, in slow-growing mycobacteria, the type VII secretion system ESX-5 plays a major role in the integrity and stability of the capsule. We have identified PPE10 as the ESX-5 substrate responsible for this effect. Mutants in esx-5 and ppe10 both have impaired capsule integrity as well as reduced surface hydrophobicity. Electron microscopy, immunoblot and flow cytometry analyses demonstrated reduced amounts of surface localized proteins and glycolipids, and morphological differences in the capsular layer. Since capsular proteins secreted by the ESX-1 system are important virulence factors, we tested the effect of the mutations that cause capsular defects on virulence mechanisms. Both esx-5 and ppe10 mutants of Mycobacterium marinum were shown to be impaired in ESX-1-dependent hemolysis. In agreement with this, the ppe10 and esx5 mutants showed reduced recruitment of ubiquitin in early macrophage infection and intermediate attenuation in zebrafish embryos. These results provide a pivotal role for the ESX-5 secretion system and its substrate PPE10, in the capsular integrity of pathogenic mycobacteria. These findings open up new roads for research on the mycobacterial capsule and its role in virulence and immune modulation. PMID:27280885

[Enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to Salmonella Typhi lipopolysaccharide O and capsular polysaccharide Vi antigens in persons from outbreak of typhoid fever].

PubMed

Rastawicki, Waldemar; Kałużewski, Stanisław

2015-01-01

The laboratory diagnosis of typhoid fever is dependent upon either isolation of S. Typhi from a clinical sample or the detection of raised titers of serum antibodies in the Widal test or the passive hemagglutination assay (PHA). In this study we evaluated the usefulness of ELISA for detection of antibodies to S. Typhi lipopolysaccharide O and capsular polysaccharide Vi antigens in the sera of persons from outbreak of typhoid fever. Fifteen serum samples from patients with laboratory confirmed typhoid fever and 140 sera from persons suspected for contact with typhoid fever patients from outbreak in 1974/75 in Poland were tested by ELISA. Additionally, as the control group, we tested 115 sera from blood donors for the presence of S. Typhi anti-LPS and anti-Vi antibodies. Anti-LPS and anti-Vi antibodies were detected in 80% and 53.3% of sera obtained from patients with laboratory confirmed typhoid fever, respectively. The high percentages of positive results in ELISA were also noted in the group of persons suspected for contact with typhoid fever patients (51.4% and 45%) but not in the group of blood donors (7.8% and 6.1%, respectively). The ELISA could be a useful tool for the serological diagnosis of typhoid fever in patients who have clinical symptoms but are culture negative, especially during massive outbreaks of typhoid fever.

[Etiopathogenesis and treatment of breast capsular contracture].

PubMed

Pereira Leite, Luis; Correia Sá, Inês; Marques, Marisa

2013-01-01

Capsular contracture is a chronic and the most frequent complication of augmentation mammoplasty with breast implants and the main cause of patient's and surgeon's dissatisfaction. The mammary capsule consists of a fibrous tissue that surrounds the implant that may contract, changing the shape and consistency of the breast. In its advanced stage is accompanied by pronounced deformity, hardness and pain, being indicated for surgical treatment. All the articles indexed on PubMed through the search 'capsular contracture' (2000 - January 2012) were reviewed and were included the articles of greater interest in terms of etiology, prophylaxis and treatment. Articles referred in relevant publications were also examined. Everything indicates that its etiology is multifactorial; the etiopathology of breast capsular contracture continues being subject of multiple pre-clinical investigations. There are many studies performed in order to prevent the onset of capsular contracture but, although promising results, little is set for its application on clinical practice. The capsulectomy/capsulotomy continues being the gold standard treatment although the future may undergo non invasive techniques, at least in mild stages of disease. Although the surgical techniques and the quality of breast implants have been improving drastically in recent years, capsular contracture remains a real complication with great incidence and that continues affecting thousands of women all over the world.

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.

In Vivo Healing after Capsular Plication in an Ovine Shoulder Model

PubMed Central

Kelly, BT; Turner, AS; Bansal, M; Terry, M; Wolf, BR; Warren, RF; Altchek, DW; Allen, AA

2005-01-01

Traditionally, arthroscopic management of shoulder instability has been reserved for patients with isolated Bankart lesions without any capsular laxity or injury. To date, there are no animal studies evaluating the healing potential of capsular plication and/or capsulo-labral repair. The purpose of this in vivo animal study was to determine if the histological capsular healing of an open capsular plication simulating an arthroscopic plication is equivalent to the more traditional open capsular shift involving cutting and advancing the capsule. Twenty-six skeletally mature sheep were randomized to either an open capsular plication simulating arthroscopic plication (n=13), or an open traditional capsular shift (n=13). A sham operation (n=4) was also performed involving exposure to visualize the capsule. Normal non-operated control shoulders were also analyzed. A pathologist blinded to the treatment evaluated both hematoxylin and eosin (H&E) sections and polarized light microscopy. Qualitative scoring evaluated fibrosis, mucinous degeneration, fat necrosis, granuloma formation, vascularity, inflammatory infiltrate and hemosiderin (0 to 3 points). Both the capsular plication and open shift groups demonstrated healing by fibrosis at the site of surgical manipulation. There were no statistical differences in the capsular healing responses between the two groups with regard to fibrosis, granuloma formation and vascularity. The open shift group demonstrated significantly more mucinous degeneration (p=0.038). Fat necrosis was present in 4/13 specimens in the open shift group and none in the capsular plication specimens. Both groups demonstrated disorganized collagen formation under polarized light microscopy. There were no differences between non-operated control specimens and sham surgery specimens. Our findings support the hypothesis that histologic capsular healing is equivalent between the plication group and the open shift group. In addition, the open shift group

[Insertional mutation in the AZOBR_p60120 gene is accompanied by defects in the synthesis of lipopolysaccharide and calcofluor-binding polysaccharides in the bacterium Azospirillum brasilense Sp245].

PubMed

Katsy, E I; Prilipov, A G

2015-03-01

In the bacterium Azospirillum brasilense Sp245, extracellular calcofluor-binding polysaccharides (Cal+ phenotype) and two types of lipopolysaccharides, LPSI and LPSII, were previously identified. These lipopolysaccharides share the same repeating O-polysaccharide unit but have different antigenic structures and different charges of their O-polysaccharides and/or core oligosaccharides. Several dozens of predicted genes involved in the biosynthesis of polysaccharides have been localized in the AZOBR_p6 plasmid of strain Sp245 (GenBank accession no. HE577333). In the present work, it was demonstrated that an artificial transposon Omegon-Km had inserted into the central region of the AZOBR_p60120 gene in the A. brasilense Sp245 LPSI- Cal- KM252 mutant. In A. brasilense strain Sp245, this plasmid gene encodes a putative glycosyltransferase containing conserved domains characteristic of the enzymes participating in the synthesis of O-polysaccharides and capsular polysaccharides (accession no. YP004987664). In mutant KM252, a respective predicted protein is expected to be completely inactivated. As a result of the analysis of the EcoRI fragment of the AZOBR_p6 plasmid, encompassing the AZOBR_p60120 gene and a number of other loci, novel data on the structure of AZOBR_p6 were obtained: an approximately 5-kb gap (GenBank accession no. KM189439) was closed in the nucleotide sequence of this plasmid.

[Detection of putative polysaccharide biosynthesis genes in Azospirillum brasilense strains from serogroups I and II].

PubMed

Petrova, L P; Prilipov, A G; Katsy, E I

2017-01-01

It is known that in Azospirillum brasilense strains Sp245 and SR75 included in serogroup I, the repeat units of their O-polysaccharides consist of five residues of D-rhamnose, and in strain SR15, of four; and the heteropolymeric O-polysaccharide of A. brasilense type strain Sp7 from serogroup II contains not less than five types of repeat units. In the present work, a complex of nondegenerate primers to the genes of A. brasilense Sp245 plasmids AZOBR_p6, AZOBR_p3, and AZOBR_p2, which encode putative enzymes for the biosynthesis of core oligosaccharide and O-polysaccharide of lipopolysaccharide, capsular polysaccharides, and exopolysaccharides, was proposed. By using the designed primers, products of the expected sizes were synthesized in polymerase chain reactions on genomic DNA of A. brasilense Sp245, SR75, SR15, and Sp7 in 36, 29, 23, and 12 cases, respectively. As a result of sequencing of a number of amplicons, a high (86–99%) level of identity of the corresponding putative polysaccharide biosynthesis genes in three A. brasilense strains from serogroup I was detected. In a blotting-hybridization reaction with the biotin-labeled DNA of the A. brasilense gene AZOBR_p60122 coding for putative permease of the ABC transporter of polysaccharides, localization of the homologous gene in ~120-MDa plasmids of the bacteria A. brasilense SR15 and SR75 was revealed.

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

Phagocytic resistance of Escherichia coli K-1 isolates and relationship to virulence.

PubMed Central

Weinstein, R; Young, L S

1978-01-01

Blood culture isolates from 133 episodes of Escherichia coli bacteremia were typed for K-1 capsular antigen by immunodiffusion, utilizing equine antiserum raised against meningococcal group B polysaccharide. Twenty-six percent (34 of 133) of these isolates were positive for K-1 antigen. These 133 strains, 34 K-1 and 99 non-K-1, were tested for susceptibility to phagocytosis. K-1 strains were found to be more resistant to clearance (27%) than non-K-1 strains (71%) when tested in an in vitro opsonophagocytic/killing assay containing normal human granulocytes and plasma. Additional studies demonstrated that resistance was due to decreased phagocytosis rather than diminished intraleukocytic killing. K-1 strains obtained from stool showed a similar degree of resistance to phagocytosis when compared with K-1 blood isolates. A comparison of clinical data on non-neonatal patients with E. coli K-1 and non-K-1 bacteremia showed no significant differences in mortality for these two groups. The incidence of shock for patients bacteremic with K-1 strains (74%) was significantly greater than that for patients bacteremic with non-K-1 strains (33%). These differences are attributed to the increased resistance to phagocytosis observed for K-1 versus non-K-1 E. coli isolates. Images PMID:370149

Actinobacillus actinomycetemcomitans Y4 capsular polysaccharide induces IL-1β mRNA expression through the JNK pathway in differentiated THP-1 cells

PubMed Central

Iwata, T; Mitani, A; Ishihara, Y; Tanaka, S; Yamamoto, G; Kikuchi, T; Naganawa, T; Matsumura, Y; Suga, T; Koide, M; Sobue, T; Suzuki, T; Noguchi, T

2005-01-01

Capsular polysaccharide from Actinobacillus actinomycetemcomitans Y4 (Y4 CP) induces bone resorption in a mouse organ culture system and osteoclast formation in mouse bone marrow cultures, as reported in previous studies. We also found that Y4 CP inhibits the release of interleukin (IL)-6 and IL-8 from human gingival fibroblast (HGF). Thus Y4 CP induces various responses in localized tissue and leads to the secretion of several cytokines. However, the effects of Y4 CP on human monocytes/macrophages are still unclear. In this study, THP-1 cells, which are a human monocytic cell line, were stimulated with Y4 CP, and we measured gene expression in inflammatory cytokine and signal transduction pathways. IL-1β and tumour necrosis factor (TNF)-α mRNA were induced from Y4 CP-treated THP-1 cells. IL-1β mRNA expression was increased according to the dose of Y4 CP, and in a time-dependent manner. IL-1β mRNA expression induced by Y4 CP (100 µg/ml) was approximately 7- to 10-fold greater than that in the control by real-time PCR analysis. Furthermore, neither PD98059, a specific inhibitor of extracellular signal-regulated kinase nor SB203580, a specific inhibitor of p38 kinase prevented the IL-1β expression induced by Y4 CP. However, JNK Inhibitor II, a specific inhibitor of c-Jun N-terminal kinase (JNK) prevented the IL-1β mRNA expression induced by Y4 CP in a concentration-dependent manner. These results indicate that Y4 CP-mediated JNK pathways play an important role in the regulation of IL-1β mRNA. Therefore, Y4 CP-transduced signals for IL-1β induction in the antibacterial action of macrophages may provide a therapeutic strategy for periodontitis. PMID:15996190

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. Copyright © 2014 Elsevier B.V. All rights reserved.

H-NS Nucleoid Protein Controls Virulence Features of Klebsiella pneumoniae by Regulating the Expression of Type 3 Pili and the Capsule Polysaccharide.

PubMed

Ares, Miguel A; Fernández-Vázquez, José L; Rosales-Reyes, Roberto; Jarillo-Quijada, Ma Dolores; von Bargen, Kristine; Torres, Javier; González-y-Merchand, Jorge A; Alcántar-Curiel, María D; De la Cruz, Miguel A

2016-01-01

Klebsiella pneumoniae is an opportunistic pathogen causing nosocomial infections. Main virulence determinants of K. pneumoniae are pili, capsular polysaccharide, lipopolysaccharide, and siderophores. The histone-like nucleoid-structuring protein (H-NS) is a pleiotropic regulator found in several gram-negative pathogens. It has functions both as an architectural component of the nucleoid and as a global regulator of gene expression. We generated a Δhns mutant and evaluated the role of the H-NS nucleoid protein on the virulence features of K. pneumoniae. A Δhns mutant down-regulated the mrkA pilin gene and biofilm formation was affected. In contrast, capsule expression was derepressed in the absence of H-NS conferring a hypermucoviscous phenotype. Moreover, H-NS deficiency affected the K. pneumoniae adherence to epithelial cells such as A549 and HeLa cells. In infection experiments using RAW264.7 and THP-1 differentiated macrophages, the Δhns mutant was less phagocytized than the wild-type strain. This phenotype was likely due to the low adherence to these phagocytic cells. Taken together, our data indicate that H-NS nucleoid protein is a crucial regulator of both T3P and CPS of K. pneumoniae.

Comparative characterization of physicochemical properties and bioactivities of polysaccharides from selected medicinal mushrooms.

PubMed

Su, Chun-Han; Lai, Min-Nan; Lin, Ching-Chuan; Ng, Lean-Teik

2016-05-01

Mushroom polysaccharides have been known to possess various pharmacological activities. However, information on their chemical and biological differences between mushrooms remains limited. In this study, we aimed to examine the differences in physicochemical characteristics of polysaccharides prepared from Antrodia cinnamomea (AC-P), Coriolus versicolor (CV-P), Grifola frondosa (GF-P), Ganoderma lucidum (GL-P), and Phellinus linteus (PL-P), followed by evaluating their inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Results showed that under similar conditions of preparation, the monosaccharide composition of polysaccharides varied between different mushrooms, and glucose was the predominant monosaccharide, followed by galactose and mannose. AC-P and GF-P contained the highest amount of (1,3;1,6)-β-D-glucans. The degree of branching of (1,3;1,6)-β-D-glucans in all polysaccharides ranged from 0.21 to 0.26, with the exception of GF-P (0.38). The molecular weights of different polysaccharides showed diverse distributions; AC-P, CV-P, and GF-P contained two major macromolecular populations (< 30 and >200 kDa) and possessed triple-helix conformation, whereas GL-P (10.2 kDa) and PL-P (15.5 kDa) only had a low molecular weight population without triple-helix structure. These polysaccharides showed different inhibitory potency on NO production in LPS-stimulated RAW264.7 cells.

Survey of potential factors involved in the low frequency of CP5 and CP8 expression in Staphylococcus aureus isolates from mastitis of dairy cattle from Argentina, Chile, and Uruguay.

PubMed

Ambroggio, Maria Belen; Perrig, Melina Soledad; Camussone, Cecilia; Pujato, Nazarena; Bertón, Alicia; Gianneechini, Edgardo; Alvarez, Silvia; Marcipar, Ivan Sergio; Calvinho, Luis Fernando; Barbagelata, Maria Sol

2018-05-03

Staphylococcus aureus produces capsular polysaccharides (CPs) both in vivo and under defined culture conditions being serotypes 5 and 8 the most prevalent. S. aureus isolates that fail to produce CP5 or CP8 are defined as non-typeable (NT). Loss of capsule expression, however, may lead to S. aureus persistence in a chronically infected host. The prevalence of NT strains of S. aureus isolated from bovine mastitis varies according to the geographic origin of the strain. The aims of this work were to detect phenotypically and genotypically the capsular profile of 144 S. aureus isolated from bovine mastitis in Argentina, Chile, and Uruguay and explore the factors that are considered to be associated with capsule expression as presence of IS257, IScap, and agr typing of non-related collection. The detection of the IS257, IScap, cap genes, and agr typing was performed using PCR. The detection and quantification of capsular polysaccharide production were performed by ELISA assays. We found that 96% of the S. aureus isolates investigated carried cap5(8) genes but over 75% of strains do not express capsule in the three countries studied. However, only 6 isolates from Argentina carried the IScap element that totally suppressed the expression of the capsule, suggesting that other factors could influence on CP expression. Moreover, the agrI/NT association was statistically significant suggesting that this profile is a phenomenon observed not only in other parts of the world but also in our region.

Capsular Sialyltransferase Specificity Mediates Different Phenotypes in Streptococcus suis and Group B Streptococcus

PubMed Central

Roy, David; Takamatsu, Daisuke; Okura, Masatoshi; Goyette-Desjardins, Guillaume; Van Calsteren, Marie-Rose; Dumesnil, Audrey; Gottschalk, Marcelo; Segura, Mariela

2018-01-01

The capsular polysaccharide (CPS) represents a key virulence factor for most encapsulated streptococci. Streptococcus suis and Group B Streptococcus (GBS) are both well-encapsulated pathogens of clinical importance in veterinary and/or human medicine and responsible for invasive systemic diseases. S. suis and GBS are the only Gram-positive bacteria which express a sialylated CPS at their surface. An important difference between these two sialylated CPSs is the linkage between the side-chain terminal galactose and sialic acid, being α-2,6 for S. suis but α-2,3 for GBS. It is still unclear how sialic acid may affect CPS production and, consequently, the pathogenesis of the disease caused by these two bacterial pathogens. Here, we investigated the role of sialic acid and the putative effect of sialic acid linkage modification in CPS synthesis using inter-species allelic exchange mutagenesis. To this aim, a new molecular biogenetic approach to express CPS with modified sialic acid linkage was developed. We showed that sialic acid (and its α-2,6 linkage) is crucial for S. suis CPS synthesis, whereas for GBS, CPS synthesis may occur in presence of an α-2,6 sialyltransferase or in absence of sialic acid moiety. To evaluate the effect of the CPS composition/structure on sialyltransferase activity, two distinct capsular serotypes within each bacterial species were compared (S. suis serotypes 2 and 14 and GBS serotypes III and V). It was demonstrated that the observed differences in sialyltransferase activity and specificity between S. suis and GBS were serotype unrestricted. This is the first time that a study investigates the interspecies exchange of capsular sialyltransferase genes in Gram-positive bacteria. The obtained mutants represent novel tools that could be used to further investigate the immunomodulatory properties of sialylated CPSs. Finally, in spite of common CPS structural characteristics and similarities in the cps loci, sialic acid exerts differential

CT arthrography of capsular structures of the shoulder.

PubMed

Rafii, M; Firooznia, H; Golimbu, C; Minkoff, J; Bonamo, J

1986-02-01

The capsular mechanism of the shoulder joint consists of the joint capsule, which is strengthened by the glenohumeral ligaments and the rotator cuff, the glenoid labrum, and a variable number of synovial recesses. Although the fibrous capsule is a lax structure, the normal function of the capsular mechanism makes it an effective barrier against anterior dislocation, particularly in external rotation. There has been a tendency in the past to overestimate the role of the glenoid labrum in stability of the shoulder joint. In patients with instability, the significance of the capsular attachment or its anomalous insertions to the glenoid has not been adequately recognized. Labral tears may develop as secondary lesions due to repeated dislocations and subluxations rather than representing the primary lesion responsible for instability. Operative visualization of capsular defects or detachments is often difficult. Prior knowledge of these lesions can effectively help the choice of an appropriate surgical procedure and reduce operating time. The results of computed tomographic (CT) arthrography of the shoulder joint in 45 patients are reported and the normal and pathologic variations of the joint capsule and particularly the capsular insertions are described. Configuration of the joint recesses and the glenoid labrum are also evaluated. These CT findings were correlated and verified by surgery or arthroscopy in 26 cases.

Isolation and structural features of an antiradical polysaccharide of Capsicum annuum that interacts with BSA.

PubMed

Majee, Sujay Kumar; Ray, Sayani; Ghosh, Kanika; Micard, Valérie; Ray, Bimalendu

2015-04-01

Red peppers, Capsicum annuum, are used worldwide as spices, foods and medicines. Herein, we have analyzed an antiradical polysaccharide isolated from red peppers through successive acetate buffer extraction. This macromolecule was purified using graded precipitation with ethanol, α-amylase treatment, deproteination and anion-exchange chromatography. This highly-branched polysaccharide (360 kDa) was esterified with phenolic acids and contained a (1,3)-linked-β-Galp chain substituted at O-6 by (1,6)-linked-β-Galp residues. The latter was substituted at O-3 by (1,5)- and (1,3,5)-linked-α-Araf residues, and non-reducing end-units of α-Araf and β-Galp. The antiradical potential of this polysaccharide was comparable to standard antioxidants. The phenolic acid residues were the functional sites. This polysaccharide could form complex with bovine serum albumin having binding constant K = 5.24 × 10(6)/M and change its microenvironment. Thus, aqueous extraction method provides a macromolecule that stimulates biological responses; this emphasizes the significance of red pepper as dietary antioxidant. Copyright © 2015 Elsevier B.V. All rights reserved.

Sulfated Polysaccharides in Marine Sponges: Extraction Methods and Anti-HIV Activity

PubMed Central

Esteves, Ana I. S.; Nicolai, Marisa; Humanes, Madalena; Goncalves, Joao

2011-01-01

The extraction, fractionation and HIV-1 inhibition potential of polysaccharides extracted from three species of marine sponges, Erylus discophorus, Cliona celata and Stelletta sp., collected in the Northeastern Atlantic, is presented in this work. The anti-HIV activity of 23 polysaccharide pellets and three crude extracts was tested. Crude extracts prepared from Erylus discophorus specimens were all highly active against HIV-1 (90 to 95% inhibition). Cliona celata pellets showed low polysaccharide content (bellow 38.5%) and almost no anti-HIV activity (<10% inhibition). Stelletta sp. pellets, although quite rich in polysaccharide (up to 97.3%), showed only modest bioactivity (<36% HIV-1 inhibition). Erylus discophorus pellets were among the richest in terms of polysaccharide content (up to 98%) and the most active against HIV-1 (up to 95% inhibition). Chromatographic fractionation of the polysaccharide pellet obtained from a specimen of Erylus discophorus (B161) yielded only modestly active fractions. However, we could infer that the active molecule is most probably a high molecular weight sulfated polysaccharide (>2000 kDa), whose mechanism is possibly preventing viral attachment and entry (fusion inhibitor). PMID:21339952

The Pneumococcal Serotype 15C Capsule Is Partially O-Acetylated and Allows for Limited Evasion of 23-Valent Pneumococcal Polysaccharide Vaccine-Elicited Anti-Serotype 15B Antibodies

PubMed Central

Spencer, Brady L.; Shenoy, Anukul T.; Orihuela, Carlos J.

2017-01-01

ABSTRACT As a species, Streptococcus pneumoniae (the pneumococcus) utilizes a diverse array of capsular polysaccharides to evade the host. In contrast to large variations in sugar composition and linkage formation, O-acetylation is a subtle capsular modification that nonetheless has a large impact on capsular shielding and recognition of the capsule by vaccine-elicited antibodies. Serotype 15B, which is included in the 23-valent pneumococcal polysaccharide vaccine (PPV23), carries the putative O-acetyltransferase gene wciZ. The coding sequence of wciZ contains eight consecutive TA repeats [(TA)8]. Replication slippage is thought to result in the addition or loss of TA repeats, subsequently causing frameshift and truncation of WciZ to yield a nonacetylated serotype, 15C. Using sensitive serological tools, we show that serotype 15C isolates whose wciZ contains seven or nine TA repeats retain partial O-acetylation, while serotype 15C isolates whose wciZ contains six TA repeats have barely detectable O-acetylation. We confirmed by inhibition enzyme-linked immunosorbent assay that (TA)7 serotype 15C is ∼0.1% as acetylated as serotype 15B, while serotype 15X is nonacetylated. To eliminate the impact of genetic background, we created isogenic serotype 15B, (TA)7 serotype 15C, and 15BΔwciZ (15X) strains and found that reduction or absence of WciZ-mediated O-acetylation did not affect capsular shielding from phagocytes, biofilm formation, adhesion to nasopharyngeal cells, desiccation tolerance, or murine colonization. Sera from PPV23-immunized persons opsonized serotype 15B significantly but only slightly better than serotypes 15C and 15X; thus, PPV23 may not result in expansion of serotype 15C. PMID:28637806

The Pneumococcal Serotype 15C Capsule Is Partially O-Acetylated and Allows for Limited Evasion of 23-Valent Pneumococcal Polysaccharide Vaccine-Elicited Anti-Serotype 15B Antibodies.

PubMed

Spencer, Brady L; Shenoy, Anukul T; Orihuela, Carlos J; Nahm, Moon H

2017-08-01

As a species, Streptococcus pneumoniae (the pneumococcus) utilizes a diverse array of capsular polysaccharides to evade the host. In contrast to large variations in sugar composition and linkage formation, O-acetylation is a subtle capsular modification that nonetheless has a large impact on capsular shielding and recognition of the capsule by vaccine-elicited antibodies. Serotype 15B, which is included in the 23-valent pneumococcal polysaccharide vaccine (PPV23), carries the putative O-acetyltransferase gene wciZ The coding sequence of wciZ contains eight consecutive TA repeats [(TA) 8 ]. Replication slippage is thought to result in the addition or loss of TA repeats, subsequently causing frameshift and truncation of WciZ to yield a nonacetylated serotype, 15C. Using sensitive serological tools, we show that serotype 15C isolates whose wciZ contains seven or nine TA repeats retain partial O-acetylation, while serotype 15C isolates whose wciZ contains six TA repeats have barely detectable O-acetylation. We confirmed by inhibition enzyme-linked immunosorbent assay that (TA) 7 serotype 15C is ∼0.1% as acetylated as serotype 15B, while serotype 15X is nonacetylated. To eliminate the impact of genetic background, we created isogenic serotype 15B, (TA) 7 serotype 15C, and 15BΔ wciZ (15X) strains and found that reduction or absence of WciZ-mediated O-acetylation did not affect capsular shielding from phagocytes, biofilm formation, adhesion to nasopharyngeal cells, desiccation tolerance, or murine colonization. Sera from PPV23-immunized persons opsonized serotype 15B significantly but only slightly better than serotypes 15C and 15X; thus, PPV23 may not result in expansion of serotype 15C. Copyright © 2017 American Society for Microbiology.

Navicula sp. Sulfated Polysaccharide Gels Induced by Fe(III): Rheology and Microstructure

PubMed Central

Fimbres-Olivarría, Diana; López-Elías, José Antonio; Carvajal-Millán, Elizabeth; Márquez-Escalante, Jorge Alberto; Martínez-Córdova, Luis Rafael; Miranda-Baeza, Anselmo; Enríquez-Ocaña, Fernando; Valdéz-Holguín, José Eduardo; Brown-Bojórquez, Francisco

2016-01-01

A sulfated polysaccharide extracted from Navicula sp. presented a yield of 4.4 (% w/w dry biomass basis). Analysis of the polysaccharide using gas chromatography showed that this polysaccharide contained glucose (29%), galactose (21%), rhamnose (10%), xylose (5%) and mannose (4%). This polysaccharide presented an average molecular weight of 107 kDa. Scanning electron microscopy (SEM) micrographs showed that the lyophilized Navicula sp. polysaccharide is an amorphous solid with particles of irregular shapes and sharp angles. The polysaccharide at 1% (w/v) solution in water formed gels in the presence of 0.4% (w/v) FeCl3, showing elastic and viscous moduli of 1 and 0.7 Pa, respectively. SEM analysis performed on the lyophilized gel showed a compact pore structure, with a pore size of approximately 150 nm. Very few studies on the gelation of sulfated polysaccharides using trivalent ions exist in the literature, and, to the best of our knowledge, this study is the first to describe the gelation of sulfated polysaccharides extracted from Navicula sp. PMID:27483255

Navicula sp. Sulfated Polysaccharide Gels Induced by Fe(III): Rheology and Microstructure.

PubMed

Fimbres-Olivarría, Diana; López-Elías, José Antonio; Carvajal-Millán, Elizabeth; Márquez-Escalante, Jorge Alberto; Martínez-Córdova, Luis Rafael; Miranda-Baeza, Anselmo; Enríquez-Ocaña, Fernando; Valdéz-Holguín, José Eduardo; Brown-Bojórquez, Francisco

2016-07-30

A sulfated polysaccharide extracted from Navicula sp. presented a yield of 4.4 (% w/w dry biomass basis). Analysis of the polysaccharide using gas chromatography showed that this polysaccharide contained glucose (29%), galactose (21%), rhamnose (10%), xylose (5%) and mannose (4%). This polysaccharide presented an average molecular weight of 107 kDa. Scanning electron microscopy (SEM) micrographs showed that the lyophilized Navicula sp. polysaccharide is an amorphous solid with particles of irregular shapes and sharp angles. The polysaccharide at 1% (w/v) solution in water formed gels in the presence of 0.4% (w/v) FeCl₃, showing elastic and viscous moduli of 1 and 0.7 Pa, respectively. SEM analysis performed on the lyophilized gel showed a compact pore structure, with a pore size of approximately 150 nm. Very few studies on the gelation of sulfated polysaccharides using trivalent ions exist in the literature, and, to the best of our knowledge, this study is the first to describe the gelation of sulfated polysaccharides extracted from Navicula sp.

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

Biomechanical Effects of Capsular Shift in the Treatment of Hip Microinstability: Creation and Testing of a Novel Hip Instability Model.

PubMed

Jackson, Timothy J; Peterson, Alexander B; Akeda, Masaki; Estess, Allyson; McGarry, Michelle H; Adamson, Gregory J; Lee, Thay Q

2016-03-01

A capsular shift procedure has been described for the treatment of hip instability; however, the biomechanical effects of such a shift are unknown. To create a cadaveric model of hip capsule laxity and evaluate the biomechanical effects of a capsular shift used to treat hip instability on this model. Controlled laboratory study. Eight cadaveric hips with an average age of 58.5 years were tested with a custom hip testing system in 6 conditions: intact, vented, instability, capsulotomy, side-to-side repair, and capsular shift. To create the hip model, the capsule was stretched in extension under 35 N·m of torque for 1 hour in neutral rotation. Measurements included internal and external rotation with 1.5 N·m of torque at 5 positions: 5° of extension and 0°, 15°, 30°, and 45° of flexion for each of the above conditions. The degree of maximum extension with 5 N·m of torque and the amount of femoral distraction with 40 N and 80 N of force were measured. Statistical analysis was performed by use of repeated-measures analysis of variance with Tukey post hoc analysis. The instability state significantly increased internal rotation at all flexion angles and increased distraction compared with the intact state. The capsulotomy condition resulted in significantly increased external rotation and internal rotation at all positions, increased distraction, and maximum extension compared with the intact state. The side-to-side repair condition restored internal rotation back to the instability state but not to the intact state at 5° of extension and 0° of flexion. The capsular shift state significantly decreased internal rotation compared with the instability state at 5° of extension and 0° and 15° of flexion. The capsular shift and side-to-side repair conditions had similar effects on external rotation at all flexion-extension positions. The capsular shift state decreased distraction and maximum extension compared with the instability state, but the side

Antibody response of swine to outer membrane components of Haemophilus pleuropneumoniae during infection.

PubMed Central

Rapp, V J; Ross, R F

1986-01-01

Sera from pigs infected with Haemophilus (Actinobacillus) pleuropneumoniae were tested for antibodies to outer membrane proteins (OMPs) of the organism by immunoblotting. Convalescent sera were produced in naturally born, colostrum-fed pigs and in cesarean-derived, colostrum-deprived pigs given H. pleuropneumoniae serotype 5 intranasally twice at 5-week intervals. Sera, collected at weekly intervals, were reacted with Sarkosyl-insoluble, OMP-enriched preparations of H. pleuropneumoniae which had been separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electrophoretically transferred to nitrocellulose. Antibodies were detected to OMPs with an apparent molecular weight of 16,500 (16.5K OMP); to 29K, 38.5K, 43.5K, 45K, 49.5K, and 66.5K OMPs; and to several high-molecular-weight (greater than or equal to 94,000) OMPs, but not to the major 42K OMP. Antibodies to the heat-modifiable OMP (29K/43.5K) and the 38.5K OMP were detected in sera from noninfected pigs. Antibodies were also detected to two broad 54,000- and 95,000-molecular-weight bands which did not stain with Coomassie blue, stained with silver nitrate, resisted proteinase K digestion, and were eliminated by oxidation with sodium metaperiodate. This indicates that the 54,000- and 95,000-molecular-weight bands represent polysaccharide, possibly capsular or lipopolysaccharide immunogens. Adsorption of sera with cells from the homologous serotype 5 strain removed antibodies to the 45K, 49.5K, 66.5K, and greater than or equal to 94K OMPs and to the two polysaccharide bands, indicating that these antibodies were directed primarily to surface-exposed epitopes. When tested with OMP preparations from other serotype 5 strains, heterogeneity was apparent, both in the reactions with OMPs and with the polysaccharide bands. Silver staining of proteinase K-treated, whole-cell lysates from serotype 5 strains also indicated variable expression of the polysaccharide bands. Sera also reacted with OMPs from

Analysis of compositional monosaccharides in fungus polysaccharides by capillary zone electrophoresis.

PubMed

Hu, Yuanyuan; Wang, Tong; Yang, Xingbin; Zhao, Yan

2014-02-15

A rapid analytical method of capillary zone electrophoresis (CZE) was established for the simultaneous separation and determination of 10 monosaccharides (aldoses and uronic acids). The monosaccharides were labeled with 1-phenyl-3-methyl-5-pyrazolone (PMP), and subsequently separated using an uncoated capillary (50 μm i.d. × 58.5 cm) and detected by UV at 245 nm with pH 11.0, 175 mM borate buffer at voltage 20 kV and capillary temperature 25 °C by CZE. The 10 PMP-labeled monosaccharides were rapidly baseline separated within 20 min. The optimized CZE method was successfully applied to the simultaneous separation and identification of the monosaccharide composition in Termitomyces albuminosus polysaccharides (TAPs) and Panus giganteus polysaccharides (PGPs). The quantitative recovery of the component monosaccharides in the fungus polysaccharides was in the range of 92.0-101.0% and the CV value was lower than 3.5%. The results demonstrate that the proposed CZE method is precise and practical for the monosaccharide analysis of fungus polysaccharides. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hericium erinaceus polysaccharide-protein HEG-5 inhibits SGC-7901 cell growth via cell cycle arrest and apoptosis.

PubMed

Zan, Xinyi; Cui, Fengjie; Li, Yunhong; Yang, Yan; Wu, Di; Sun, Wenjing; Ping, Lifeng

2015-05-01

HEG-5 is a novel polysaccharide-protein purified from the fermented mycelia of Hericium erinaceus CZ-2. The present study aims to investigate the effects of HEG-5 on proliferation, cell cycle and apoptosis of human gastric cancer cells SGC-7901. Here, we first uncover that HEG-5 significantly inhibited the proliferation and colony formation of SGC-7901 cells by promoting apoptosis and cell cycle arrest at S phase. RT-PCR and Western blot analysis suggested that HEG-5 could decrease the expressions of Bcl2, PI3K and AKT1, while increase the expressions of Caspase-8, Caspase-3, p53, CDK4, Bax and Bad. These findings indicated that the Caspase-8/-3-dependent, p53-dependent mitochondrial-mediated and PI3k/Akt signaling pathways involved in the molecular events of HEG-5 induced apoptosis and cell cycle arrest. Thus, our study provides in vitro evidence that HEG-5 may be taken as a potential candidate for treating gastric cancer. Copyright © 2015 Elsevier B.V. All rights reserved.

Pneumococcal LytR Protein Is Required for the Surface Attachment of Both Capsular Polysaccharide and Teichoic Acids: Essential for Pneumococcal Virulence.

PubMed

Ye, Weijie; Zhang, Jinghui; Shu, Zhaoche; Yin, Yibing; Zhang, Xuemei; Wu, Kaifeng

2018-01-01

The LytR-Cps-Psr family proteins are commonly present in Gram-positive bacteria, which have been shown to implicate in anchoring cell wall-related glycopolymers to the peptidoglycan. Here, we report the cellular function of SPD_1741 (LytR) in Streptococcus pneumoniae and its role in virulence of pneumococci. Pneumococcal Δ lytR mutants have been successfully constructed by replacing the lytR gene with erm cassette. The role of LytR in pneumococcal growth was determined by growth experiments, and surface accessibility of the LytR protein was analyzed using flow cytometry. Transmission electron microscopy (TEM) and immunoblotting were used to reveal the changes in capsular polysaccharide (CPS). Dot blot and ELISA were used to quantify the amount of teichoic acids (TAs). The contribution of LytR on bacterial virulence was assessed using in vitro phagocytosis assays and infection experiments. Compared to the wild-type strain, the Δ lytR mutant showed a defect in growth which merely grew to a maximal OD 620 of 0.2 in the liquid medium. The growth of the Δ lytR mutant could be restored by addition of recombinant ΔTM-LytR protein in culture medium in a dose-dependent manner. TEM results showed that the D39Δ lytR mutant was impaired in the surface attachment of CPS. Deletion of lytR gene also impaired the retention of TAs on the surface of pneumococci. The reduction of CPS and TAs on the pneumocccal cells were confirmed using Dot blot and ELISA assays. Compared to wild-type D39, the Δ lytR mutant was more susceptible to the phagocytosis. Animal studies showed that the ability to colonize the nasophaynx and virulence of pneumococci were affected by impairment of the lytR gene. Collectively, these results suggest that pneumococcal LytR is involved in anchoring both the CPS and TAs to cell wall, which is important for virulence of pneumococci.

Effects of Ultrasound-guided intra-articular ketorolac injection with capsular distension.

PubMed

Ahn, Jae Ki; Kim, Jongwoo; Lee, Sang Jae; Park, Yongbum; Bae, Byung; Lee, Woo

2015-01-01

Frozen shoulder is a painful condition with gradual onset and loss of range of motion in the glenohumeral joint. To investigate the efficacy of ultrasound(US)-guided intra-articular (IA) ketorolac injection with capsular distension compared with steroid injection alone in patients with frozen shoulder by assessing pain relief, functional improvements, and range of motion at 1,3 and 6 months after the last injections. Between January 2009 and December 2012, 121 patient were treated with US-guided IA steroid injection or IA ketorolac injection with capsular distension for frozen shoulder. Patients (n= 57) of US-guided IA steroid injection group were administered with a mixture of 0.5% lidocaine (4 ml) plus triamcinolone (40 mg/ml; 1 ml) and patients (n= 64) of US-guided IA ketorolac injection with capsular distension group were administered by using 0.5% lidocaine (19 mL) plus ketorolac (30 mg/ml; 1 mL) for capsular distension. Outcome measurement was assessed by Shoulder Pain and Disability Index (SPADI), Verbal Numeric pain Scale (VNS) and passive range of motion (ROM) before injections and at 1, 3 and 6 months after the last injections. We regarded the outcomes as a success if patients obtained significant pain relief (as measured by > 50% improvement in the VNS score and 20 point improvement in the SPASI) at 1, 3 and 6 months after the last injections. SPADI, VNS and passive ROM were improved 1, 3 and 6 months after the last injections in both groups. The statistical differences were not observed in SPADI, VNS between groups (p< 0.05). Successful treatment rate were not significantly different between the groups as well as in 1, 3 and 6 month outcomes. However, greater improvement was found in a matter of range of motion in patients receiving IA ketorolac injection with capsular distension than participants receiving US-guided IA steroid injection alone. Significant differences in improvement at 3 and 6 months were observed for shoulder passive abduction and

Posterior capsular rent: Prevention and management.

PubMed

Chakrabarti, Arup; Nazm, Nazneen

2017-12-01

This review article deals with a potentially sight threatening complication - rupture of the posterior capsule - during cataract surgery. Cataract surgery is the most commonly performed surgical procedure in ophthalmology and despite tremendous technical and technological advancements, posterior capsular rent (PCR) still occurs. PCR occurs both in the hands of experienced senior surgeons and the neophyte surgeons, although with a higher frequency in the latter group. Additionally, certain types of cataracts are prone to this development. If managed properly in a timely manner the eventual outcome may be no different from that of an uncomplicated case. However, improper management may lead to serious complications with a higher incidence of permanent visual disability. The article covers the management of posterior capsular rent from two perspectives: 1. Identifying patients at higher risk and measures to manage such patients by surgical discipline, and 2. Intraoperative management of posterior capsular rent and various case scenarios to minimize long-term complications.This review is written for experienced and not-so-experienced eye surgeons alike to understand and manage PCR.

Polysaccharides from Tricholoma matsutake and Lentinus edodes enhance 5-fluorouracil-mediated H22 cell growth inhibition.

PubMed

Ren, Ming; Ye, Lingyan; Hao, Xiaoshi; Ren, Zhixing; Ren, Shuping; Xu, Kun; Li, Juan

2014-06-01

Few studies have investigated the effects produced by combinations of polysaccharides and chemotherapeutic drugs in cancer treatment. We hypothesized that a combination of polysaccharides (COP) from Lentinus edodes and Tricholoma matsutake would improve the efficacy of 5-fluorouracil (5-FU)-mediated inhibition of H22 cell growth. Mice were injected H22 cells and then treated with either 5-FU, polysaccharides from Tricholoma matsutake (PTM), polysaccharides from Lentinus edodes (PL), PTM+PL, 5-FU+PTM, 5-FU+ PL, or 5-FU + COP. The tumor weight and volume, and splenic CD4 + and CD8 + T cell frequencies, were determined. Additionally, splenic natural killer (NK) cell and cytotoxic T lymphocyte (CTL) activities were assessed and the serum levels of tumor necrosis factor-alpha (TNF-alpha), Interleukin-2 (IL-2), and Interferon-gamma (IFN-gamma) were measured. Compared with mice from the control, 5-FU, PL, PTM, PTM + PL, 5-FU + PL, and 5-FU + PTM groups, mice treated with 5-FU + COP showed: (a) significantly reduced tumor weight and volume (P < 0.05); (b) significantly higher serum levels of TNF-alpha, IL-2, and IFN-gamma (P < 0.05); (c) significantly increased CD4+ and CD8+ T cell frequencies in the spleen (P < 0.05); and (d) significantly increased splenic NK cell and CTL activities (P < 0.05). The tumor weight and volume in mice treated with 5-FU+PL or 5-FU+PTM were significantly reduced compared with mice treated with 5-FU alone (P < 0.05). Serum levels of TNF-alpha, IL-2, and IFN-gamma, frequencies of CD4 + and CD8+ T cells in the spleen, and splenic NK and CTL activities were also significantly increased in mice treated with 5-FU+PL or 5-FU+PTM compared with mice treated with 5-FU alone (P < 0.05). Polysaccharides from Lentinus edodes and Tricholoma matsutake could enhance the efficacy of 5-FU-mediated H22 cell growth inhibition.

Selenizing astragalus polysaccharide attenuates PCV2 replication promotion caused by oxidative stress through autophagy inhibition via PI3K/AKT activation.

PubMed

Liu, Dandan; Xu, Jing; Qian, Gang; Hamid, Mohammed; Gan, Fang; Chen, Xingxiang; Huang, Kehe

2018-03-01

Our previous studies have shown that oxidative stress could promote the porcine circovirus type 2 (PCV2) replication, and astragalus polysaccharide (APS)/selenium could suppress PCV2 replication. However, whether selenizing astragalus polysaccharide (sAPS) provides protection against oxidative stress-induced PCV2 replication promotion and the mechanism involved remain unclear. The present study aimed to explore the mechanism of the PCV2 replication promotion induced by oxidative stress and a novel pharmacotherapeutic approach involving the regulation of autophagy of sAPS. Our results showed that H 2 O 2 promoted PCV2 replication via enhancing autophagy by using 3-methyladenine (3-MA) and autophagy-related gene 5 (ATG5) knockdown. Sodium selenite, APS, the mixture of sodium selenite and APS, and sAPS significantly inhibited H 2 O 2 -induced PCV2 replication promotion, respectively. Among these, sAPS exerted maximal inhibitory effect. sAPS could also significantly inhibit autophagy activated by H 2 O 2 and increase the Akt and mTOR phosphorylation. Moreover, LY294002, the specific phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) inhibitor, significantly alleviated the effects of sAPS on autophagy and PCV2 replication. Taken together, we conclude that H 2 O 2 promotes PCV2 replication by inducing autophagy and sAPS attenuates the PCV2 replication promotion through autophagy inhibition via PI3K/AKT activation. Copyright © 2017 Elsevier B.V. All rights reserved.

Hepatic capsular retraction: spectrum of diagnosis at MRI

PubMed Central

Mons, Antoine; Braidy, Chadi; Montoriol, Pierre François; Garcier, Jean-Marc; Vilgrain, Valérie

2014-01-01

Hepatic capsular retraction is an imaging feature that deserves the attention of the radiologist. Hepatic capsular retraction is associated with a number of hepatic lesions, benign or malignant, treated or untreated. The purpose of this pictorial review is to discuss the most common benign and malignant hepatic lesions associated with this feature with an emphasis on magnetic resonance imaging (MRI). PMID:25535571

[Capsular retensioning in anterior unidirectional glenohumeral instability].

PubMed

Benítez Pozos, Leonel; Martínez Molina, Oscar; Castañeda Landa, Ezequiel

2007-01-01

To present the experience of the Orthopedics Service PEMEX South Central Hospital in the management of anterior unidirectional shoulder instability with an arthroscopic technique consisting of capsular retensioning either combined with other anatomical repair procedures or alone. Thirty-one patients with anterior unidirectional shoulder instability operated-on between January 1999 and December 2005 were included. Fourteen patients underwent capsular retensioning and radiofrequency, and in 17 patients, capsular retensioning was combined with suture anchors. Patients with a history of relapsing glenohumeral dislocations and subluxations, with anterior instability with or without associated Bankart lesions were selected; all of them were young. The results were assessed considering basically the occurrence of instability during the postoperative follow-up. No cases of recurring instability occurred. Two cases had neuroma and one experienced irritation of the suture site. Six patients had residual limitation of combined lateral rotation and abduction movements, of a mean of 10 degrees compared with the healthy contralateral side. The most frequent incident was the leak of solutions to the soft tissues. Capsular retensioning, whether combined or not with other anatomical repair techniques, has proven to result in a highly satisfactory rate of glenohumeral stabilization in cases of anterior unidirectional instabilities. The arthroscopic approach offers the well-known advantages of causing less damage to the soft tissues, and a shorter time to starting rehabilitation therapy and exercises.

Forces on intraocular lens haptics induced by capsular fibrosis. An experimental study.

PubMed

Guthoff, R; Abramo, F; Draeger, J; Chumbley, L C; Lang, G K; Neumann, W

1990-01-01

Electronic dynamometry measurements, performed upon intraocular lens (IOL) haptics of prototype one-piece three-loop silicone lenses, accurately defined the relationships between elastic force and haptic displacement. Lens implantations in the capsular bag of dogs (loop span equal to capsular bag diameter, loops underformed immediately after the operation) were evaluated macrophotographically 5-8 months postoperatively. The highly constant elastic property of silicon rubber permitted quantitative correlation of subsequent in vivo haptic displacement with the resultant force vectors responsible for tissue contraction. The lens optics were well centered in 17 (85%) and slightly offcenter in 3 (15%) of 20 implanted eyes. Of the 60 supporting loops, 28 could be visualized sufficiently well to permit reliable haptic measurement. Of these 28, 20 (71%) were clearly displaced, ranging from 0.45 mm away from to 1.4 mm towards the lens' optic center. These extremes represented resultant vector forces of 0.20 and 1.23 mN respectively. Quantitative vector analysis permits better understanding of IOL-capsular interactions.

Carboxymethylated degraded polysaccharides from Enteromorpha prolifera: Preparation and in vitro antioxidant activity.

PubMed

Shi, Mei-Jia; Wei, Xiaoyi; Xu, Jie; Chen, Bing-Jie; Zhao, De-Yin; Cui, Shuai; Zhou, Tao

2017-01-15

In order to improve the bioactivities of the polysaccharide from Enteromorpha prolifera (PE), crude PE (Mw 1400kDa) was degraded to low molecular weight polysaccharide (44kDa) in the presence of hydrogen peroxide/ascorbic acid, followed by carboxymethylation. The reaction conditions for carboxymethylation of degraded polysaccharide (DPE) were optimized by Response Surface Methodology. The carboxymethyled degraded polysaccharide (CDPE) obtained under optimized conditions, with a degree of carboxymethylation of 0.849, was characterized by FT-IR and (13)C NMR. The molecular weight of CDPE was measured to be 53.7kDa. CDPE was evaluated for its antioxidant activity by determining the ability to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide anion radicals, and by determining the ferric reducing power. The antioxidant activity of CDPE was found to be greatly improved in comparison with degraded polysaccharide (DPE) and crude polysaccharide from Enteromorpha prolifera (PE). Copyright © 2016 Elsevier Ltd. All rights reserved.

Structural characterization and in vitro antitumor activity of a novel polysaccharide from Taxus yunnanensis.

PubMed

Yan, Chunyan; Yin, Yin; Zhang, Dawei; Yang, Wei; Yu, Rongmin

2013-07-25

The shrub, Taxus yunnanensis is famed as the source of the important anticancer drug, paclitaxel. But research on its polysaccharides contents has been scarce. The present research aimed to investigate the polysaccharide content of T. yunnanensis leaves and study the antitumor activities of isolated polysaccharide(s) using human tumor cells (K-562 and MCF). A novel heteropolysaccharide (TMP70W) was isolated and purified by anion-exchange and gel-permeation chromatography. Its molecular weight was 36.94 kDa and structural features were elucidated by partial acid hydrolysis, periodate oxidation-Smith degradation, methylation analysis, GC-MS, HPAEC-PAD, FT-IR, and NMR. The repeating unit of TMP70W had a backbone composed of (1→5)-linked-α-l-Araf, (1→2,5)-linked-α-l-Araf, and (1→6)-linked-β-d-Galp with a branch of α-d-Glcp-(1→2)-α-d-Galp-(1→ at the position of C-2 of arabinose. TMP70W displayed mild cytotoxicity against K562 cells with the IC50 value of 39.63 ± 2.37 μg/mL and inhibitory activity against MCF-7 cells (32.08 ± 0.39% at the concentration of 400 μg/mL) in a concentration-dependent manner. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of ultrasonic treatment on immunological activities of polysaccharides from adlay.

PubMed

Yao, Yang; Zhu, Yingying; Gao, Yue; Ren, Guixing

2015-09-01

Alkali-extractable polysaccharides from the seed of adlay and their two polysaccharide sub-fractions (AAP-1 and AAP-2) were isolated and purified by anion-exchange and gel filtration chromatography. Ultrasonic treatment was put in place to obtain AAP-1' and AAP-2'. Average molecular weights (Mws) of AAP-1, AAP-1', AAP-2, and AAP-2' were 94.2 kDa, 63.1 kDa, 82.3 kDa, and 60.4 kDa, respectively. Monosaccharides composition analysis indicated that AAP-1 and AAP-1' were composed of Rha, Ara, Glc, and Gal in a molar ratio of 1.1:0.4:0.7:0.5 and 1.4:1.6:0.4:0.7. AAP-2 and AAP-2' were composed of Xyl, Rha, Gal and Glc in a molar percent of 0.4:1.4:1.6:0.5 and 0.3:1.6:1.1:0.7. In vitro study showed that AAP-1, AAP-1', AAP-2, and AAP-2' were all able to encourage the production of secretory molecules (NO, TNF-α and IL-6) of RAW264.7 murine macrophages in concentrations determines manner. AAP-2' seemed to be the most potent and induced significantly higher the NO production. These findings suggest that the ultrasonic polysaccharides isolated in our study have immune potentiation effects on macrophages and should serve as a beneficial health food. Copyright © 2015 Elsevier B.V. All rights reserved.

The diversity of Klebsiella pneumoniae surface polysaccharides.

PubMed

Follador, Rainer; Heinz, Eva; Wyres, Kelly L; Ellington, Matthew J; Kowarik, Michael; Holt, Kathryn E; Thomson, Nicholas R

2016-08-01

Klebsiella pneumoniae is considered an urgent health concern due to the emergence of multi-drug-resistant strains for which vaccination offers a potential remedy. Vaccines based on surface polysaccharides are highly promising but need to address the high diversity of surface-exposed polysaccharides, synthesized as O-antigens (lipopolysaccharide, LPS) and K-antigens (capsule polysaccharide, CPS), present in K. pneumoniae . We present a comprehensive and clinically relevant study of the diversity of O- and K-antigen biosynthesis gene clusters across a global collection of over 500 K. pneumoniae whole-genome sequences and the seroepidemiology of human isolates from different infection types. Our study defines the genetic diversity of O- and K-antigen biosynthesis cluster sequences across this collection, identifying sequences for known serotypes as well as identifying novel LPS and CPS gene clusters found in circulating contemporary isolates. Serotypes O1, O2 and O3 were most prevalent in our sample set, accounting for approximately 80 % of all infections. In contrast, K serotypes showed an order of magnitude higher diversity and differ among infection types. In addition we investigated a potential association of O or K serotypes with phylogenetic lineage, infection type and the presence of known virulence genes. K1 and K2 serotypes, which are associated with hypervirulent K. pneumoniae , were associated with a higher abundance of virulence genes and more diverse O serotypes compared to other common K serotypes.

The diversity of Klebsiella pneumoniae surface polysaccharides

PubMed Central

Heinz, Eva; Wyres, Kelly L.; Ellington, Matthew J.; Kowarik, Michael; Holt, Kathryn E.; Thomson, Nicholas R.

2016-01-01

Klebsiella pneumoniae is considered an urgent health concern due to the emergence of multi-drug-resistant strains for which vaccination offers a potential remedy. Vaccines based on surface polysaccharides are highly promising but need to address the high diversity of surface-exposed polysaccharides, synthesized as O-antigens (lipopolysaccharide, LPS) and K-antigens (capsule polysaccharide, CPS), present in K. pneumoniae. We present a comprehensive and clinically relevant study of the diversity of O- and K-antigen biosynthesis gene clusters across a global collection of over 500 K. pneumoniae whole-genome sequences and the seroepidemiology of human isolates from different infection types. Our study defines the genetic diversity of O- and K-antigen biosynthesis cluster sequences across this collection, identifying sequences for known serotypes as well as identifying novel LPS and CPS gene clusters found in circulating contemporary isolates. Serotypes O1, O2 and O3 were most prevalent in our sample set, accounting for approximately 80 % of all infections. In contrast, K serotypes showed an order of magnitude higher diversity and differ among infection types. In addition we investigated a potential association of O or K serotypes with phylogenetic lineage, infection type and the presence of known virulence genes. K1 and K2 serotypes, which are associated with hypervirulent K. pneumoniae, were associated with a higher abundance of virulence genes and more diverse O serotypes compared to other common K serotypes. PMID:28348868

Noninvasive Shock Wave Treatment for Capsular Contractures After Breast Augmentation: A Rabbit Study.

PubMed

Chen, Po Chou; Kuo, Shyh Ming; Jao, Jo Chi; Yang, Shiou Wen; Hsu, Ching Wen; Wu, Yu Chiuan

2016-06-01

Capsular contracture is the most common complication of breast augmentation. Although numerous procedures are intended to prevent capsular contracture, their efficacy does not satisfy surgeons or patients. In the present study, we used shock waves to develop innovative protocols to treat capsular contracture in rabbits. We used shock waves to treat capsular contracture in a rabbit model. Six clinical parameters were evaluated to determine the treatment efficacy of shock waves on the pathological histology of capsular contracture. Dual-flip-angle T1-mapping magnetic resonance imaging was used to confirm the pathological findings. Among the parameters, myxoid change, vascular proliferation, and lymphoplasma cell infiltration around the capsule increased more after treatment than they did in a control group. Capsular thickness, inner thinner collagen layer, and capsule wall collagen deposition decreased after shock wave treatment; only the inner thinner collagen layer and capsule wall collagen deposition changed significantly. The MRI findings for both scar thickness and water content were consistent with pathological biology findings. This was the first pilot study and trial to treat capsular contractures using shock waves. We found that shock waves can cause changes in the structure or the composition of capsular contracture. We conclude that the treatment could decrease water content, loosen structure, decrease collagen deposition, and might alleviate scar formation from capsular contracture. We believe that the treatment could be a viable remedy for capsular contractures. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Excessive radiofrequency application: effects on capsular tissue in an animal model.

PubMed

Wolf, Brian R; Heiner, Anneliese D; Albright, John P; Nepola, James V

2005-01-01

Capsular attenuation has been seen after thermal capsulorrhaphy surgery. The purpose of this study was to evaluate the mechanical, histologic, and morphologic effects on capsular tissue after cumulative applications of radiofrequency energy. Ovine patellofemoral capsular tissue was treated with 1, 2, 4, or 8 applications of bipolar radiofrequency energy and then analyzed. No acute capsular ablation or destruction was seen grossly, even in the 8-application group. No definitive visual clues that excessive radiofrequency energy had been applied were seen. There was significant shrinkage and loss of tensile stiffness for all thermal application groups. Given the small sample sizes, post-application failure load, percent relaxation, and stiffness were not observed to be significantly different among the groups. Cumulative applications produced minimal further tissue shrinkage but were accompanied by larger, though not statistically significant, mechanical property losses and increased depth of tissue penetration. These findings suggest that there is no benefit to repeated applications of radiofrequency energy to capsular tissue.

Population-based study of capsular warning syndrome and prognosis after early recurrent TIA.

PubMed

Paul, Nicola L M; Simoni, Michela; Chandratheva, Arvind; Rothwell, Peter M

2012-09-25

Many guidelines recommend emergency assessment for patients with ≥2 TIAs within 7 days, perhaps in recognition of the capsular warning syndrome. However, it is unclear whether all patients with multiple TIAs are at high early risk of stroke and whether treatable underlying pathologies are more prevalent in this group. We studied clinical characteristics, Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification, and risk of stroke in 1,000 consecutive patients with incident and recurrent TIAs in a prospective, population-based study (Oxford Vascular Study). Of 1,000 patients with TIAs, 170 had a further TIA within 7 days (105 within 24 hours). Multiple TIAs were not associated with carotid stenosis or atrial fibrillation, and much of the 10.6 (95% confidence interval [CI] 6.5-15.9) risk of stroke during the 7 days after the first TIA was due to patients with small-vessel disease (SVD) etiology (10 of 24 vs 8 of 146, odds ratio [OR] = 12.3, 95% CI 3.7-41.9, p < 0.0001), particularly those with motor weakness (i.e., capsular warning syndrome) compared with hemisensory events (9 of 15 [60%], 95% CI 35.3-84.7 vs 1 of 9 [11.1%], 95% CI 0-31.7, p = 0.03). The 7-day risk of stroke after a recurrent TIA was similar to the risk after a single TIA in patients with non-SVD TIA (8 of 146 [5.5%] vs 76 of 830 [9.2%], OR = 0.58, 95% CI 0.25-1.3, p = 0.20). Of the 9 patients with stroke after a capsular warning syndrome, all had the recurrent TIA within 24 hours after the first TIA, and the subsequent stroke occurred within 72 hours of the second TIA in 8. The ABCD2 scores of all preceding TIAs were ≥4 in all 9 patients with capsular warning syndrome before stroke. Capsular warning syndrome is rare (1.5% of TIA presentations) but has a poor prognosis (7-day stroke risk of 60%). Otherwise, recurrent TIA within 7 days is not associated with a greater stroke risk than that after a single TIA.

Medial capsular interpositional arthroplasty for severe hallux rigidus.

PubMed

Hahn, Michael Patrick; Gerhardt, Nels; Thordarson, David B

2009-06-01

Multiple surgical options have been described for severe hallux rigidus. One option is capsular interpositional arthroplasty. We report our initial results with a technique using the thicker medial capsule as our interpositional material instead of the dorsal capsule and extensor hallucis brevis (EHB). Twenty-two patients with grade IV hallux rigidus underwent minimal proximal phalanx resection (modified Keller) with preservation of the flexor hallucis brevis (FHB) insertion and medial capsular interpositional arthroplasty. Postoperative AOFAS hallux MTP-IP scores (mean 77.8), and SF-36 scores (mean 68.7 on physical function, 79.5 role limitations) demonstrated clinical improvement compared to historical controls. Alignment and stability were well maintained (mean preoperative HV angle of 11.8 degrees, mean postoperative HV angle of 13.0 degrees). Dorsiflexion/plantarflexion arc of motion showed sustained improvement (mean 38.4 degrees preoperative, mean 62.3 degrees postoperative). These results are comparable to other forms of interpositional arthroplasty and arthrodesis for end stage arthritis of the hallux MTPJ.

Surface antigens contribute differently to the pathophysiological features in serotype K1 and K2 Klebsiella pneumoniae strains isolated from liver abscesses.

PubMed

Yeh, Kuo-Ming; Chiu, Sheng-Kung; Lin, Chii-Lan; Huang, Li-Yueh; Tsai, Yu-Kuo; Chang, Jen-Chang; Lin, Jung-Chung; Chang, Feng-Yee; Siu, Leung-Kei

2016-01-01

The virulence role of surface antigens in a single serotype of Klebsiella pneumoniae strain have been studied, but little is known about whether their contribution will vary with serotype. To investigate the role of K and O antigen in hyper-virulent strains, we constructed O and K antigen deficient mutants from serotype K1 STL43 and K2 TSGH strains from patients with liver abscess, and characterized their virulence in according to the abscess formation and resistance to neutrophil phagocytosis, serum, and bacterial clearance in liver. Both of K1 and K2-antigen mutants lost their wildtype resistance to neutrophil phagocytosis and hepatic clearance, and failed to cause abscess formation. K2-antigen mutant became serum susceptible while K1-antigen mutant maintained its resistance to serum killing. The amount of glucuronic acid, indicating the amount of capsular polysaccharide (CPS, K antigen), was inversed proportional to the rate of phagocytosis. O-antigen mutant of serotype K1 strains had significantly more amount of CPS, and more resistant to neutrophil phagocytosis than its wildtype counterpart. O-antigen mutants of serotype K1 and K2 strains lost their wildtype serum resistance, and kept resistant to neutrophil phagocytosis. While both mutants lacked the same O1 antigen, O-antigen mutant of serotype K1 became susceptible to liver clearance and cause mild abscess formation, but its serotype K2 counterpart maintained these wildtype virulence. We conclude that the contribution of surface antigens to virulence of K. pneumoniae strains varies with serotypes.

Vancomycin tolerance in clinical and laboratory Streptococcus pneumoniae isolates depends on reduced enzyme activity of the major LytA autolysin or cooperation between CiaH histidine kinase and capsular polysaccharide.

PubMed

Moscoso, Miriam; Domenech, Mirian; García, Ernesto

2010-08-01

Vancomycin is frequently added to standard therapy for pneumococcal meningitis. Although vancomycin-resistant Streptococcus pneumoniae strains have not been isolated, reports on the emergence of vancomycin-tolerant pneumococci are a cause of concern. To date, the molecular basis of vancomycin tolerance in S. pneumoniae is essentially unknown. We examined two vancomycin-tolerant clinical isolates, i.e. a purported autolysin negative (LytA(-)), serotype 23F isolate (strain S3) and the serotype 14 strain 'Tupelo', which is considered a paradigm of vancomycin tolerance. S3 was characterized here as carrying a frameshift mutation in the lytA gene encoding the main pneumococcal autolysin. The vancomycin tolerance of strain S3 was abolished by transformation to the autolysin-proficient phenotype. The original Tupelo strain was discovered to be a mixture: a strain showing a vancomycin-tolerant phenotype (Tupelo_VT) and a vancomycin-nontolerant strain (Tupelo_VNT). The two strains differed only in terms of a single mutation in the ciaH gene present in the VT strain. Most interestingly, although the vancomycin tolerance of Tupelo_VT could be overcome by increasing the LytA dosage upon transformation by a multicopy plasmid or by externally adding the autolysin, we show that vancomycin tolerance in S. pneumoniae requires the simultaneous presence of a mutated CiaH histidine kinase and capsular polysaccharide. © 2010 Blackwell Publishing Ltd.

Relationship between Cell Surface Carbohydrates and Intrastrain Variation on Opsonophagocytosis of Streptococcus pneumoniae

PubMed Central

Kim, Jean O.; Romero-Steiner, Sandra; Sørensen, Uffe B. Skov; Blom, Jens; Carvalho, M.; Barnard, S.; Carlone, George; Weiser, Jeffrey N.

1999-01-01

Streptococcus pneumoniae undergoes spontaneous phase variation between a transparent and an opaque colony phenotype, the latter being more virulent in a murine model of sepsis. Opaque pneumococci have previously been shown to express lower amounts of C polysaccharide (cell wall teichoic acid) and in this study were shown to have a higher content of capsular polysaccharide by immunoelectron microscopy. This report then examined the relationship between expression of these two cell surface carbohydrate structures and their relative contribution to the increased virulence of opaque variants. Comparison of genetically related strains showed that the differential content of capsular polysaccharide did not affect the amount of teichoic acid as measured by a capture enzyme-linked immunosorbent assay (ELISA). In contrast, when the teichoic acid structure was altered by replacing choline in the growth medium with structural analogs, the quantity of capsular polysaccharide as measured by a capture ELISA was decreased, demonstrating a linkage in the expression of the two surface carbohydrate structures. A standardized assay was used to assess the relative contribution of cell surface carbohydrates to opsonophagocytosis. The opaque variants required 1.2- to 30-fold more immune human serum to achieve 50% opsonophagocytic killing than did related transparent variants (types 6B and 9V). The opsonophagocytic titer was proportional to the quantity of capsular polysaccharide rather than teichoic acid. The major factor in binding of the opsonin, C-reactive protein (CRP), was also the amount of capsular polysaccharide rather than the teichoic acid ligand. Only for the transparent variant (type 6B), which bound more CRP, was there enhanced opsonophagocytic killing in the presence of this serum protein. Increased expression of capsular polysaccharide, therefore, appeared to be the major factor in the decreased opsonophagocytic killing of opaque pneumococci. PMID:10225891

[Posterior capsule opacification, capsular bag distension syndrome, and anterior capsular phimosis: A retrospective cohort study].

PubMed

González-Martín-Moro, J; González-López, J J; Gómez-Sanz, F; Zarallo-Gallardo, J; Cobo-Soriano, R

2015-02-01

To determine the incidence and the risk factors involved in the development of the three main postoperative capsular complications: posterior capsule opacification (PCO), capsular bag distension syndrome (CBDS), and anterior capsular phimosis syndrome (ACP). A retrospective cohort study was conducted on 801 patients submitted to cataract surgery in the ophthalmology unit of Hospital del Henares (Madrid) from March 2, 2009 to February 28, 2010. Computerized clinical charts were reviewed during July 2012. PCO was studied using the Kaplan-Meier method (log rank test). A total of 167 patients developed PCO. No association could be demonstrated between PCO and age, sex, diabetes mellitus, phaco technique, IOL model, tamsulosin intake, glaucoma, and age-related macular degeneration. Three patients developed CBDS, all of them have received and Akreos Adapt AO(®) (Bausch & Lomb). Two of them were young men who had received surgery for posterior subcapsular cataracts. Three patients developed ACP, 2 of whom had received a MicroSlim(®) IOL (PhysIOL). No association was found between PCO and any of the studied variables. Male gender, young age, subcapsular cataract and large non-angulated lens such as Akreos Adapt AO(®) could be associated with CBDS. ACP could be more frequent when microincision IOLs (like MicroSlim(®)) are implanted. Copyright © 2013 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Structure features and in vitro hypoglycemic activities of polysaccharides from different species of Maidong.

PubMed

Gong, Yajun; Zhang, Jie; Gao, Fei; Zhou, Jiewen; Xiang, Zhinan; Zhou, Chenggao; Wan, Luosheng; Chen, Jiachun

2017-10-01

Structures and in vitro hypoglycemic activities of polysaccharides from different species of Maidong were studied. The primary structures of polysaccharides were elucidated on the basis of GC, GC-MS, infrared, NMR and periodate oxidation-Smith degradation. Liriope spicata polysaccharide (LSP), Ophiopogon japonicus polysaccharide (OJP) and Liriope muscari polysaccharide (LMP) were composed of β-fructose and α-glucose. The average molecular weights of LSP, OJP and LMP were 4742, 4925 and 4138Da with polydispersity indexes of 1.1, 1.2 and 1.1, respectively. The backbones of polysaccharides were formed by Fruf-(2→, →2)-Fruf-(6→, →6)-Glcp-(1→ and →1, 2)-Fruf-(6→ with a molar ratio of 5.0:18.2:1.0:5.3 (LSP), 6.8:15.8:1.0:5.8 (OJP), 8.3:12.3:1.0:3.9 (LMP), respectively. The RT-PCR and western blot analysis indicated that LSP, LMP and OJP increased the expression of PI3K, AKT, InsR, PPARγ and decreased the expression of PTP1B in mRNA level and protein level in IR HepG2 cells. Furthermore, glucose consumption was increased after treated with polysaccharides. These results revealed that LSP, OJP and LMP had potential anti-diabetic effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biotechnological engineering of heparin/heparan sulphate: a novel area of multi-target drug discovery.

PubMed

Rusnati, Marco; Oreste, Pasqua; Zoppetti, Giorgio; Presta, Marco

2005-01-01

Heparin is a sulphated glycosaminoglycan currently used as an anticoagulant and antithrombotic drug. It consists largely of 2-O-sulphated IdoA not l&r arrow N, 6-O-disulphated GlcN disaccharide units. Other disaccharides containing unsulphated IdoA or GlcA and N-sulphated or N-acetylated GlcN are also present as minor components. This heterogeneity is more pronounced in heparan sulphate (HS), where the low-sulphated disaccharides are the most abundant. Heparin/HS bind to a variety of biologically active polypeptides, including enzymes, growth factors and cytokines, and viral proteins. This capacity can be exploited to design multi-target heparin/HS-derived drugs for pharmacological interventions in a variety of pathologic conditions besides coagulation and thrombosis, including neoplasia and viral infection. The capsular K5 polysaccharide from Escherichia coli has the same structure as the heparin precursor N-acetyl heparosan. The possibility of producing K5 polysaccharide derivatives by chemical and enzymatic modifications, thus generating heparin/HS-like compounds, has been demonstrated. These K5 polysaccharide derivatives are endowed with different biological properties, including anticoagulant/antithrombotic, antineoplastic, and anti-AIDS activities. Here, the literature data are discussed and the possible therapeutic implications for this novel class of multi-target "biotechnological heparin/HS" molecules are outlined.

Group B Streptococcus and Streptococcus suis Capsular Polysaccharides Induce Chemokine Production by Dendritic Cells via Toll-Like Receptor 2- and MyD88-Dependent and -Independent Pathways

PubMed Central

Calzas, Cynthia; Goyette-Desjardins, Guillaume; Lemire, Paul; Gagnon, Fleur; Lachance, Claude; Van Calsteren, Marie-Rose

2013-01-01

Streptococcus agalactiae (also known as group B Streptococcus [GBS]) and Streptococcus suis are encapsulated streptococci causing severe septicemia and meningitis. Bacterial capsular polysaccharides (CPSs) are poorly immunogenic, but anti-CPS antibodies are essential to the host defense against encapsulated bacteria. The mechanisms underlying anti-CPS antibody responses are not fully elucidated, but the biochemistry of CPSs, particularly the presence of sialic acid, may have an immunosuppressive effect. We investigated the ability of highly purified S. suis and GBS native (sialylated) CPSs to activate dendritic cells (DCs), which are crucial actors in the initiation of humoral immunity. The influence of CPS biochemistry was studied using CPSs extracted from different serotypes within these two streptococcal species, as well as desialylated CPSs. No interleukin-1β (IL-1β), IL-6, IL-12p70, tumor necrosis factor alpha (TNF-α), or IL-10 production was observed in S. suis or GBS CPS-stimulated DCs. Moreover, these CPSs exerted immunosuppressive effects on DC activation, as a diminution of gamma interferon (IFN-γ)-induced B cell-activating factor of the tumor necrosis factor family (BAFF) expression was observed in CPS-pretreated cells. However, S. suis and GBS CPSs induced significant production of CCL3, via partially Toll-like receptor 2 (TLR2)- and myeloid differentiation factor 88 (MyD88)-dependent pathways, and CCL2, via TLR-independent mechanisms. No major influence of CPS biochemistry was observed on the capacity to induce chemokine production by DCs, indicating that DCs respond to these CPSs in a patterned way rather than a structure-dedicated manner. PMID:23774593

Development of Vaccines to Prevent Wound Infections due to Anaerobic Bacteria

DTIC Science & Technology

1982-08-01

monosaccharides are common to both. To define further these interestir.g results, we studied cross-protection of these two polysaccharides in the B. fragilis...and abscess formation. We have found that vmmunization of rats with a purified capsular polysaccharide (CP) of a B. fragilis ýtrain protects against...which protection is afforded to animals after immunization "with the capsular polysaccharide (CP) of B. fragilis. The decision to proceed along these

Genetic diversity of K-antigen gene clusters of Escherichia coli and their molecular typing using a suspension array.

PubMed

Yang, Shuang; Xi, Daoyi; Jing, Fuyi; Kong, Deju; Wu, Junli; Feng, Lu; Cao, Boyang; Wang, Lei

2018-04-01

Capsular polysaccharides (CPSs), or K-antigens, are the major surface antigens of Escherichia coli. More than 80 serologically unique K-antigens are classified into 4 groups (Groups 1-4) of capsules. Groups 1 and 4 contain the Wzy-dependent polymerization pathway and the gene clusters are in the order galF to gnd; Groups 2 and 3 contain the ABC-transporter-dependent pathway and the gene clusters consist of 3 regions, regions 1, 2 and 3. Little is known about the variations among the gene clusters. In this study, 9 serotypes of K-antigen gene clusters (K2ab, K11, K20, K24, K38, K84, K92, K96, and K102) were sequenced and correlated with their CPS chemical structures. On the basis of sequence data, a K-antigen-specific suspension array that detects 10 distinct CPSs, including the above 9 CPSs plus K30, was developed. This is the first report to catalog the genetic features of E. coli K-antigen variations and to develop a suspension array for their molecular typing. The method has a number of advantages over traditional bacteriophage and serum agglutination methods and lays the foundation for straightforward identification and detection of additional K-antigens in the future.

Central nervous system demyelinating disease protection by the human commensal Bacteroides fragilis depends on polysaccharide A expression.

PubMed

Ochoa-Repáraz, Javier; Mielcarz, Daniel W; Ditrio, Lauren E; Burroughs, Ashley R; Begum-Haque, Sakhina; Dasgupta, Suryasarathi; Kasper, Dennis L; Kasper, Lloyd H

2010-10-01

The importance of gut commensal bacteria in maintaining immune homeostasis is increasingly understood. We recently described that alteration of the gut microflora can affect a population of Foxp3(+)T(reg) cells that regulate demyelination in experimental autoimmune encephalomyelitis (EAE), the experimental model of human multiple sclerosis. We now extend our previous observations on the role of commensal bacteria in CNS demyelination, and we demonstrate that Bacteroides fragilis producing a bacterial capsular polysaccharide Ag can protect against EAE. Recolonization with wild type B. fragilis maintained resistance to EAE, whereas reconstitution with polysaccharide A-deficient B. fragilis restored EAE susceptibility. Enhanced numbers of Foxp3(+)T(reg) cells in the cervical lymph nodes were observed after intestinal recolonization with either strain of B. fragilis. Ex vivo, CD4(+)T cells obtained from mice reconstituted with wild type B. fragilis had significantly enhanced rates of conversion into IL-10-producing Foxp3(+)T(reg) cells and offered greater protection against disease. Our results suggest an important role for commensal bacterial Ags, in particular B. fragilis expressing polysaccharide A, in protecting against CNS demyelination in EAE and perhaps human multiple sclerosis.

Mycelium and polysaccharide production of Agaricus blazei Murrill by submerged fermentation.

PubMed

Lin, Jr-Hui; Yang, Shang-Shyng

2006-04-01

Over the last decade, Agaricus blazei Murrill has been studied and developed as a novel functional food in Japan, Korea, China, and Taiwan. Due to the low yields, the fruiting bodies of A. blazei Murrill are relatively expensive, and a cheap and stable source of A. blazei Murrill mycelium for commercial purposes is highly desirable. Culture media and conditions were investigated with a view to reducing the cost and improving the mycelium and polysaccharide production of A. blazei Murrill by submerged fermentation. Thirty six isolates of A. blazei Murrill were isolated from 22 fruiting bodies produced in Taiwan, and 16 of them could be successfully cultivated on mannitol-egg yolk-polymyxin medium. The isolates were identified by species-specific polymerase chain reaction (PCR) and optimized for the culture media and conditions by submerged fermentation for mycelium and polysaccharide production. Some properties of polysaccharide extract were also investigated. All of the PCR products with species-specific primers showed high identity and matched the internal transcribed spacer 1 sequences of A. blazei Murrill. The phylogenic tree of A. blazei Murrill isolates generated from random amplified polymorphic DNAs arranged all samples into 3 groups and 2 independent cases. The optimal culture media of mycelium production in submerged fermentation were 5% malt extract, 0.1% yeast extract, and 0.5% peptone at pH 6.0, while the optimal culture conditions were 200 mL medium in 500 mL Hinton flask, shaking at 90 rpm for 3 days and then shifting to 105 rpm for 5 days at 27 degrees C. Each liter of A. blazei Murrill M72 yielded 10.83 +/- 0.24 g dried mycelia weight and each liter of A. blazei Murrill M152 produced 0.251 +/- 0.004 g crude polysaccharide (3.03 +/- 0.05% of dried mycelia weight). Crude polysaccharide of A. blazei Murrill M162 contained 82.27-99.14% of total sugar and less than 1.63% of protein; it had 4 major molecular weight components (274.1, 32.7, 7.5, and 2.1 k

Inhibition of B16-BL6 melanoma lung colonies by semisynthetic sulfaminoheparosan sulfates from E. coli K5 polysaccharide.

PubMed

Poggi, Andreina; Rossi, Cosmo; Casella, Nicola; Bruno, Cristiana; Sturiale, Luisella; Dossi, Carla; Naggi, Annamaria

2002-08-01

Heparin (H), heparan sulfate (HS), and related glycosaminoglycans can inhibit cancer cell invasion, possibly due to their ability to interact with vascular growth factors, adhesion molecules, endoglycosidases, and signaling proteins, in addition to the well-known effects on the clotting system. We evaluated the antitumor activity of a series of semisynthetic sulfaminoheparosan sulfates (SAHSs) with different degree and distribution of sulfates, obtained by chemical modifications of the E. coli K5 polysaccharide, namely type A, B, and C compounds. B16-BL6 melanoma cells (10 5 cells/mouse) were injected intravenously (i.v.) in a lateral tail vein of C57BL6 mice at a dose of 0.5 mg/ mouse together with test compounds. Tumor lung nodules were significantly reduced as compared with controls only by H (95.5 +/- 1.0% inhibition), SAHS-2 (84.2 +/- 5.0% inhibition), and SAHS-4 (91.1 +/- 4.2% inhibition), among compounds tested. SAHS-2 and SAHS-4 are type B compounds, with a sulfate/carboxylate ratio similar to that of H. A typical mammalian HS showed only 54.8% inhibition. Supersulfated low-molecular-weight heparin and heparan sulfate (ssLMWH and ssLMWHS) showed an activity similar to that of unfractionated compounds. H and SAHS-4 inhibited dose dependently B16-BL6 lung colonies, with IC-50 values of 0.05 and 0.1 mg/mouse, respectively. The relationship with ex vivo anticoagulant potency was evaluated by activated partial thromboplastin time (aPTT) on mouse plasma at different time intervals after i.v. injection (0.1 to 0.5 mg/mouse) of the compound. H showed a dose-dependent anticoagulant activity lasting up to 2 hours, whereas SAHS-4 showed a potent anticoagulant effect only at a dose of 0.5 mg/mouse. Accordingly, H but not SAHS-4 consistently inhibited B16-BL6 lung colonies when given 1 hour before tumor cells. SAHS-4 derivatives, with different size and/or affinity depleted of AT binding sites, showed an inhibitory effect on B16-BL6 melanoma similar to that of SAHS-4

Prevention and cure of systemic Escherichia coli K1 infection by modification of the bacterial phenotype.

PubMed

Mushtaq, Naseem; Redpath, Maria B; Luzio, J Paul; Taylor, Peter W

2004-05-01

Escherichia coli is a common cause of meningitis and sepsis in the newborn infant, and the large majority of isolates from these infections produce a polysialic acid (PSA) capsular polysaccharide, the K1 antigen, that protects the bacterial cell from immune attack. We determined whether a capsule-depolymerizing enzyme, by removing this protective barrier, could alter the outcome of systemic infection in an animal model. Bacteriophage-derived endosialidase E (endoE) selectively degrades the PSA capsule on the surface of E. coli K1 strains. Intraperitoneal administration of small quantities of recombinant endoE (20 micro g) to 3-day-old rats, colonized with a virulent strain of K1, prevented bacteremia and death from systemic infection. The enzyme had no effect on the viability of E. coli strains but sensitized strains expressing PSA to killing by the complement system. This study demonstrates the potential therapeutic efficacy of agents that cure infections by modification of the bacterial phenotype rather than by killing or inhibition of growth of the pathogen.

Preoperative and postoperative size and movements of the lens capsular bag: ultrasound biomicroscopy analysis.

PubMed

Modesti, Marina; Pasqualitto, Giacomo; Appolloni, Rossella; Pecorella, Irene; Sourdille, Philippe

2011-10-01

To evaluate capsular bag size and accommodative movement before and after cataract surgery using ultrasound biomicroscopy (UBM) and anterior segment optical coherence tomography (AS-OCT). Ophthalmology Unit, Fabia Mater Clinic, Rome, Italy. Cohort study. Eyes having cataract surgery and monofocal intraocular lens (IOL) implantation were studied using UBM. The following parameters were measured preoperatively and 1, 2, and 12 months postoperatively: anterior chamber depth (ACD) (also by AS-OCT), capsular bag thickness, capsular bag diameter, ciliary ring diameter, sulcus-to-sulcus (STS) diameter, ciliary process-capsular bag distance, ciliary apex-capsular bag plane, and IOL tilting. The preoperative and postoperative capsular bag volumes were calculated at 12 months. The results were compared with the changes during accommodation. The study comprised 24 eyes. With the exception of the ciliary apex-capsular bag plane, which appeared to be unmodified postoperatively, all measured parameters showed significant variation after IOL implantation. Only the ACD did not change significantly during accommodation. After cataract surgery, the capsular bag stretched horizontally and with reduced vertical diameter as a result of adaptation to the implanted IOL. The capsular bag-IOL complex filled all available space, compressing the zonular fibers and almost abolishing the space between the ciliary apex and the capsular bag. There was anterior chamber deepening and a decrease in the ciliary ring diameter and STS diameter. In the absence of zonular fiber tension, the shape of the ciliary processes may be modified. No author has a financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

[Physiological response to acetic acid stress of Acetobacter pasteuranus during vinegar fermentation].

PubMed

Qi, Zhengliang; Yang, Hailin; Xia, Xiaole; Wang, Wu; Leng, Yunwei; Yu, Xiaobin; Quan, Wu

2014-03-04

The aim of the study is to propose a dynamic acetic acid resistance mechanism through analysis on response of cellular morphology, physiology and metabolism of A. pasteurianus CICIM B7003 during vinegar fermentation. Vinegar fermentation was carried out in a Frings 9 L acetator by strain B7003 and cultures were sampled at different cellular growth phases. Simultaneously, percentage of capsular polysaccharide versus dry cells weight, ratio of unsaturated fatty acids to saturated fatty acids, transcription of acetic acid resistance genes, activity of alcohol respiratory chain enzymes and ATPase were detected for these samples to assay the responses of bacterial morphology, physiology and metabolism. When acetic acid was existed, no obvious capsular polysaccharide was secreted by cells. As vinegar fermentation proceeding, percentage of capsular polysaccharide versus dry cells weight was reduced from 2.5% to 0.89%. Ratio of unsaturated fatty acids to saturated fatty acids was increased obviously which can improve membrane fluidity. Also transcription level of acetic acid resistance genes was promoted. Interestingly, activity of alcohol respiratory chain and ATPase was not inhibited but promoted obviously with acetic acid accumulation which could provide enough energy for acetic acid resistance mechanism. On the basis of the results obtained from the experiment, A. pasteurianus CICIM B7003 relies mainly on the cooperation of changes of extracellular capsular polysaccharide and membrane fatty acids, activation of acid resistance genes transcription, enhancement of activity of alcohol respiratory chain and rapid energy production to tolerate acidic environment.

Imaging late capsular block syndrome: ultrasound biomicroscopy versus Scheimpflug camera.

PubMed

Kucukevcilioglu, Murat; Hurmeric, Volkan; Erdurman, Fazıl Cuneyt; Ceylan, Osman Melih

2011-11-01

We describe 2 patients with late capsular block syndrome whose anterior chamber morphology was evaluated with ultrasound biomicroscopy and Scheimpflug imaging before and after neodymium:YAG laser capsulotomy. Pretreatment ultrasound biomicroscopy examination showed significant capsular bag distension in both patients. Scheimpflug imaging failed to capture the posterior capsule displaced far behind the intraocular lens. Automatic anterior chamber depth measurements were incorrect with Scheimpflug imaging in 1 patient. Ultrasound biomicroscopy seems to be superior to Scheimpflug imaging in eyes with extremely distended capsular bags. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Antioxidant and immunoregulatory activity of alkali-extractable polysaccharides from mung bean.

PubMed

Yao, Yang; Zhu, Yingying; Ren, Guixing

2016-03-01

Alkali-extractable polysaccharides from the seeds of mung beans and two polysaccharide sub-fractions (MAP-1 and MAP-2) were isolated and purified by anion-exchange and gel filtration chromatography. The average molecular weights (Mws) of MAP-1 and MAP-2 were 94.2 kDa and 60.4 kDa, respectively. Monosaccharide component analysis indicated that MAP-1 was composed of Rha, Ara, Glu, Gal, and GalA in a molar ratio of 1.1:0.4:0.7:0.5:0.3. MAP-2 consisted of Xyl, Rha, Gal, Glu and GalA with a relative molar ratio of 0.4:1.4:1.6:0.5:0.2. Antioxidant assays indicated that both MAP-1 and MAP-2 exhibit significant antioxidant activity in a dose-dependent manner. An in vitro study further showed that MAP-1 and MAP-2 were both able to stimulate the production of secretory molecules (NO, TNF-α and IL-6) by RAW 264.7 murine macrophages in a concentration-dependent manner. These findings suggest that the polysaccharides isolated in our study have immunoregulatory effects on macrophages and can be used as a beneficial health food. Copyright © 2015. Published by Elsevier B.V.

Assessment of the adhesive properties of the bacterial polysaccharide FucoPol.

PubMed

Araújo, Diana; Alves, Vitor D; Campos, Joana; Coelhoso, Isabel; Sevrin, Chantal; Grandfils, Christian; Freitas, Filomena; Reis, Maria A M

2016-11-01

To address the industry's interest in finding novel biobased glues, the adhesive properties of the bacterial polysaccharide FucoPol were evaluated through shear bond strength tests. A FucoPol solution was used to bond different materials, namely, wood, glass, cardboard and cellulose acetate film. The shear strength was compared to that of the same adherends bonded with commercial synthetic glues. Wood-wood joints bonded with FucoPol formulation withstood 742.2±9.8kPa shear strength without detachment. FucoPol adhesive capacity for cardboard was comparable to that of the tested commercial glues (425±8.9kPa), yielding similar shear strength values (416.0±12.9kPa), while improved performance was shown for glass (115.1±26.2kPa) and cellulose acetate film (153.7±11.3kPa) comparing to the commercial glues (67.7-97.5kPa and 79.4-92.7kPa, respectively). This study demonstrates the adhesive properties of FucoPol, opening up the opportunity of using this bacterial polysaccharide for the development of new natural water-based glues, suitable to bond different materials. Copyright © 2016 Elsevier B.V. All rights reserved.

Sucrose fed-batch strategy enhanced biomass, polysaccharide, and ganoderic acids production in fermentation of Ganoderma lucidum 5.26.

PubMed

Wei, Zhen-hua; Liu, Lianliang; Guo, Xiao-feng; Li, Yan-jun; Hou, Bao-chao; Fan, Qiu-ling; Wang, Kai-xiang; Luo, Yingdi; Zhong, Jian-jiang

2016-01-01

Ganoderma, as a Chinese traditional medicine, has multiple bioactivities. However, industrial production was limited due to low yield during Ganoderma fermentation. In this work, sucrose was found to greatly enhance intracellular polysaccharide (IPS) content and specific extracellular polysaccharide (EPS) production rate. The mechanism was studied by analyzing the activities of enzymes related to polysaccharide biosynthesis. The results revealed that sucrose regulated the activities of phosphoglucomutase and phosphoglucose isomerase. When glucose and sucrose mixture was used as carbon source, biomass, polysaccharide and ganoderic acids (GAs) production was greatly enhanced. A sucrose fed-batch strategy was developed in 10-L bioreactor, and was scaled up to 300-L bioreactor. The biomass, EPS and IPS production was 25.5, 2.9 and 4.8 g/L, respectively, which was the highest biomass and IPS production in pilot scale. This study provides information for further understanding the regulation mechanism of Ganoderma polysaccharide biosynthesis. It demonstrates that sucrose fed-batch is a useful strategy for enhancing Ganoderma biomass, polysaccharide and GAs production.

Structure analysis and anti-fatigue activity of a polysaccharide from Lepidium meyenii Walp.

PubMed

Tang, Yun; Zhu, Zhen-Yuan; Pan, Li-Chao; Sun, Huiqing; Song, Qiao-Ying; Zhang, Yongmin

2018-03-16

A polysaccharide was obtained from Lepidium meyenii Walp by hot water extraction and purification by Millipore (100 kD) and Sephadex G-200. The content of polysaccharide was examined to be 89.9% with phenol-sulfuric acid method. Its average molecular weight was estimated to be 2.213 × 10 6  Da by High Performance Gel Permeation Chromatography (HPGPC). Monosaccharide analysis showed that the polysaccharide was composed of arabinose, mannose, glucose and galactose with the molar ratio of 2.134: 1: 2.78: 2.82. After Smith degradation, methylation, infrared spectroscopy and NMR, the primary structure of the polysaccharide was identified. The backbone of the polysaccharide was composed of →4)-β-D-Galp-(1→ and →4)-α-D-Galp-(1→, while the branches were comprised of →6)-β-D-Glup-(1→, →5)- β-D-Araf-(1→, →3,6)-α-D-Manp-(1→, →3)-α-D-Galp-(1→, and α-D-Glup-(1→. The anti-fatigue effect of the polysaccharide was evaluated using exhaustive swimming test and biochemical indexes. The results indicated the polysaccharide has anti-fatigue effect.

Thickening of the inferior glenohumeral capsule: an ultrasound sign for shoulder capsular contracture.

PubMed

Michelin, Paul; Delarue, Yohann; Duparc, Fabrice; Dacher, Jean Nicolas

2013-10-01

The aim of this retrospective study was to measure the inferior glenohumeral capsule thickness of shoulders clinically affected by capsular contracture by comparison to the contralateral asymptomatic side. Bilateral shoulder ultrasound (US) examinations of 20 patients with clinically or MRI proven unilateral capsular contracture were retrospectively assessed. Inferior capsule evaluation was performed with a transducer placed within the axilla in maximally abducted shoulders. Measurements were symmetrically performed orthogonally to the inferior glenohumeral ligament (IGHL) in the axial plane; the coronal plane was used to ensure the tension of the IGHL. The significance of any difference in thickening was assessed with the Mann-Whitney test. The average thickness was 4.0 mm in shoulders with capsular contracture vs. 1.3 mm in asymptomatic contralateral shoulders (P < 0.0001). Twenty per cent of patients with capsular contracture and inferior capsule thickness increase showed US features of other painful diseases of the rotator cuff. The thickness of the inferior capsule is measurable through ultrasound examination and appears to be increased in shoulders with capsular contracture. Exploration of the inferior aspect of the shoulder joint could be added to shoulder US examination protocols for capsular contracture assessment even if other rotator cuff abnormalities are diagnosed by US. • Ultrasound is increasingly used to diagnose shoulder problems. • The thickness of the inferior glenohumeral ligament is measurable in the axilla. • The inferior glenohumeral ligament appears thickened in shoulders with capsular contracture. • Capsular contracture ultrasound features can be associated with other rotator cuff problems.

Deletion of a 77-base-pair inverted repeat element alters the synthesis of surface polysaccharides in Porphyromonas gingivalis.

PubMed

Bainbridge, Brian W; Hirano, Takanori; Grieshaber, Nicole; Davey, Mary E

2015-04-01

Bacterial cell surface glycans, such as capsular polysaccharides and lipopolysaccharides (LPS), influence host recognition and are considered key virulence determinants. The periodontal pathogen Porphyromonas gingivalis is known to display at least three different types of surface glycans: O-LPS, A-LPS, and K-antigen capsule. We have shown that PG0121 (in strain W83) encodes a DNABII histone-like protein and that this gene is transcriptionally linked to the K-antigen capsule synthesis genes, generating a large ∼19.4-kb transcript (PG0104-PG0121). Furthermore, production of capsule is deficient in a PG0121 mutant strain. In this study, we report on the identification of an antisense RNA (asRNA) molecule located within a 77-bp inverted repeat (77bpIR) element located near the 5' end of the locus. We show that overexpression of this asRNA decreases the amount of capsule produced, indicating that this asRNA can impact capsule synthesis in trans. We also demonstrate that deletion of the 77bpIR element and thereby synthesis of the large 19.4-kb transcript also diminishes, but does not eliminate, capsule synthesis. Surprisingly, LPS structures were also altered by deletion of the 77bpIR element, and reactivity to monoclonal antibodies specific to both O-LPS and A-LPS was eliminated. Additionally, reduced reactivity to these antibodies was also observed in a PG0106 mutant, indicating that this putative glycosyltransferase, which is required for capsule synthesis, is also involved in LPS synthesis in strain W83. We discuss our finding in the context of how DNABII proteins, an antisense RNA molecule, and the 77bpIR element may modulate expression of surface polysaccharides in P. gingivalis. The periodontal pathogen Porphyromonas gingivalis displays at least three different types of cell surface glycans: O-LPS, A-LPS, and K-antigen capsule. We have shown using Northern analysis that the K-antigen capsule locus encodes a large transcript (∼19.4 kb), encompassing a 77-bp

Deletion of a 77-Base-Pair Inverted Repeat Element Alters the Synthesis of Surface Polysaccharides in Porphyromonas gingivalis

PubMed Central

Bainbridge, Brian W.; Hirano, Takanori; Grieshaber, Nicole

2015-01-01

ABSTRACT Bacterial cell surface glycans, such as capsular polysaccharides and lipopolysaccharides (LPS), influence host recognition and are considered key virulence determinants. The periodontal pathogen Porphyromonas gingivalis is known to display at least three different types of surface glycans: O-LPS, A-LPS, and K-antigen capsule. We have shown that PG0121 (in strain W83) encodes a DNABII histone-like protein and that this gene is transcriptionally linked to the K-antigen capsule synthesis genes, generating a large ∼19.4-kb transcript (PG0104-PG0121). Furthermore, production of capsule is deficient in a PG0121 mutant strain. In this study, we report on the identification of an antisense RNA (asRNA) molecule located within a 77-bp inverted repeat (77bpIR) element located near the 5′ end of the locus. We show that overexpression of this asRNA decreases the amount of capsule produced, indicating that this asRNA can impact capsule synthesis in trans. We also demonstrate that deletion of the 77bpIR element and thereby synthesis of the large 19.4-kb transcript also diminishes, but does not eliminate, capsule synthesis. Surprisingly, LPS structures were also altered by deletion of the 77bpIR element, and reactivity to monoclonal antibodies specific to both O-LPS and A-LPS was eliminated. Additionally, reduced reactivity to these antibodies was also observed in a PG0106 mutant, indicating that this putative glycosyltransferase, which is required for capsule synthesis, is also involved in LPS synthesis in strain W83. We discuss our finding in the context of how DNABII proteins, an antisense RNA molecule, and the 77bpIR element may modulate expression of surface polysaccharides in P. gingivalis. IMPORTANCE The periodontal pathogen Porphyromonas gingivalis displays at least three different types of cell surface glycans: O-LPS, A-LPS, and K-antigen capsule. We have shown using Northern analysis that the K-antigen capsule locus encodes a large transcript (∼19.4 kb

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

Arabinan-rich pectic polysaccharides from buriti (Mauritia flexuosa): an Amazonian edible palm fruit.

PubMed

Cantu-Jungles, Thaisa Moro; Almeida, Carolina Pierobom de; Iacomini, Marcello; Cipriani, Thales R; Cordeiro, Lucimara M C

2015-05-20

Primary cell wall polysaccharides from aqueous extract of buriti fruit pulp (Mauritia flexuosa, an exotic tropical palm) were isolated and characterized. After freeze-thaw and α-amylase treatments, extracted polysaccharides were purified by sequential ultrafiltration through membranes. Two homogeneous fractions were obtained, SBW-100R and SBW-30R (Mw of 126 kDa and 20 kDa, respectively). Monosaccharide composition, methylation and (13)C NMR analysis showed that fraction SBW-100R contained a (1 → 5)-linked arabinan, branched at O-3 and O-2 positions, linked to a type I rhamnogalacturonan. Low amounts of these polymers were also present in fraction SBW-30R according to (13)C NMR analysis and monosaccharide composition. However, a high methyl esterified homogalacturonan (HG) was present in higher proportions. These results reinforce previous findings present in literature data which indicate that pectic polysaccharides are found in high amounts in primary cell walls of palms, which are commelinid monocotyledons. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Klebsiella pneumoniae wabG Gene: Role in Biosynthesis of the Core Lipopolysaccharide and Virulence

PubMed Central

Izquierdo, Luis; Coderch, Núria; Piqué, Nuria; Bedini, Emiliano; Michela Corsaro, Maria; Merino, Susana; Fresno, Sandra; Tomás, Juan M.; Regué, Miguel

2003-01-01

To determine the function of the wabG gene in the biosynthesis of the core lipopolysaccharide (LPS) of Klebsiella pneumoniae, we constructed wabG nonpolar mutants. Data obtained from the comparative chemical and structural analysis of LPS samples obtained from the wild type, the mutant strain, and the complemented mutant demonstrated that the wabG gene is involved in attachment to α-l-glycero-d-manno-heptopyranose II (l,d-HeppII) at the O-3 position of an α-d-galactopyranosyluronic acid (α-d-GalAp) residue. K. pneumoniae nonpolar wabG mutants were devoid of the cell-attached capsular polysaccharide but were still able to produce capsular polysaccharide. Similar results were obtained with K. pneumoniae nonpolar waaC and waaF mutants, which produce shorter LPS core molecules than do wabG mutants. Other outer core K. pneumoniae nonpolar mutants in the waa gene cluster were encapsulated. K. pneumoniae waaC, waaF, and wabG mutants were avirulent when tested in different animal models. Furthermore, these mutants were more sensitive to some hydrophobic compounds than the wild-type strains. All these characteristics were rescued by reintroduction of the waaC, waaF, and wabG genes from K. pneumoniae. PMID:14645282

Hip capsular thickness correlates with range of motion limitations in femoroacetabular impingement.

PubMed

Zhang, Kailai; de Sa, Darren; Yu, Hang; Choudur, Hema Nalini; Simunovic, Nicole; Ayeni, Olufemi Rolland

2018-03-24

Femoroacetabular impingement (FAI) is a clinical entity of the hip causing derangements in range of motion, pain, gait, and function. Computer-assisted modeling and clinical studies suggest that patients with FAI have increased capsular thickness compared to those without.A retrospective chart review was performed to assess relationships between capsular thickness, hip range of motion, and demographic factors in patients with FAI. Local Research Ethics Board approval was obtained to extract electronic medical records for 188 patients at a single institution who had undergone hip arthroscopy. Procedures were performed from 2009 to 2017 by a single, fellowship-trained, board-certified sports medicine orthopaedic surgeon. Inclusion criteria were preoperative hip range of motion testing, positive clinical impingement testing, and magnetic resonance imaging (MRI) of the affected hip. Patient demographics, hip range of motion, and time to surgery were recorded. MRIs were reviewed by a board-certified musculoskeletal radiologist blinded to clinical data. Maximum thickness of the anterior hip capsule was measured in axial, axial oblique, and sagittal oblique sequences. Anterior capsular thickness was also measured at the level of the femoral head-neck junction in axial sequences (axial midline). Axial midline capsular thickness was negatively correlated with hip flexion (r = - 0.196, p = 0.0042) and internal rotation (r = - 0.143, p = 0.0278). Significant differences were seen between genders in axial midline thickness (5.3 ± 1.4 mm males/4.8 ± 1.3 mm females, p = 0.0079), flexion (113° ± 18° males/120° ± 17° females, p = 0.0029), and internal rotation (23° ± 13° males/29° ± 12° females, p = 0.0155). Significant differences also existed between side affected in flexion (116° ± 17° right/119° ± 17° left, p = 0.0396) and internal rotation (26° ± 12° right/29° ± 13° left

Anticancer properties of polysaccharides isolated from fungi of the Basidiomycetes class.

PubMed

Lemieszek, Marta; Rzeski, Wojciech

2012-01-01

Basidiomycete mushrooms represent a valuable source of biologically active compounds with anticancer properties. This feature is primarily attributed to polysaccharides and their derivatives. The anticancer potential of polysaccharides is linked to their origin, composition and chemical structure, solubility and method of isolation. Moreover, their activity can be significantly increased by chemical modifications. Anticancer effects of polysaccharides can be expressed indirectly (immunostimulation) or directly (cell proliferation inhibition and/or apoptosis induction). Among the wide range of polysaccharides with documented anticancer properties, lentinan, polysaccharide-K (PSK) and schizophyllan deserve special attention. These polysaccharides for many years have been successfully applied in cancer treatment and their mechanism of action is the best known.

Inhibition of hydrogen peroxide induced injuring on human skin fibroblast by Ulva prolifera polysaccharide.

PubMed

Cai, Chuner; Guo, Ziye; Yang, Yayun; Geng, Zhonglei; Tang, Langlang; Zhao, Minglin; Qiu, Yuyan; Chen, Yifan; He, Peimin

2016-10-01

Ulva prolifera can protect human skin fibroblast from being injured by hydrogen peroxide. This work studied the composition of Ulva prolifera polysaccharide and identified its physicochemical properties. The results showed that the cell proliferation of 0.5mg/mL crude polysaccharide was 154.4% of that in negative control group. Moreover, ROS detection indices, including DCFH-DA, GSH-PX, MDA and CAT, indicated that crude polysaccharide could improve cellular ability to scavenge free radical and decrease the injury on human skin fibroblast by hydrogen peroxide. In purified polysaccharide, the activity of fraction P1-1 was the highest, with 174.6% of that in negative control group. The average molecular weight of P1-1 was 137kD with 18.0% of sulfate content. This work showed the inhibition of hydrogen peroxide induced injuries on human skin fibroblast by Ulva prolifera polysaccharide, which may further evaluate the application of U. prolifera on cosmetics. Copyright © 2016 Elsevier B.V. All rights reserved.

Molecular weight distribution of polysaccharides from edible seaweeds by high-performance size-exclusion chromatography (HPSEC).

PubMed

Gómez-Ordóñez, Eva; Jiménez-Escrig, Antonio; Rupérez, Pilar

2012-05-15

Biological properties of polysaccharides from seaweeds are related to their composition and structure. Many factors such as the kind of sugar, type of linkage or sulfate content of algal biopolymers exert an influence in the relationship between structure and function. Besides, the molecular weight (MW) also plays an important role. Thus, a simple, reliable and fast HPSEC method with refractive index detection was developed and optimized for the MW estimation of soluble algal polysaccharides. Chromatogram shape and repeatability of retention time was considerably improved when sodium nitrate was used instead of ultrapure water as mobile phase. Pullulan and dextran standards of different MW were used for method calibration and validation. Also, main polysaccharide standards from brown (alginate, fucoidan, laminaran) and red seaweeds (kappa- and iota-carrageenan) were used for quantification and method precision and accuracy. Relative standard deviation (RSD) of repeatability for retention time, peak areas and inter-day precision was below 0.7%, 2.5% and 2.6%, respectively, which indicated good repeatability and precision. Recoveries (96.3-109.8%) also showed its fairly good accuracy. Regarding linearity, main polysaccharide standards from brown or red seaweeds showed a highly satisfactory correlation coefficient (r>0.999). Moreover, a good sensitivity was shown, with corresponding limits of detection and quantitation in mg/mL of 0.05-0.21 and 0.16-0.31, respectively. The method was applied to the MW estimation of standard algal polysaccharides, as well as to the soluble polysaccharide fractions from the brown seaweed Saccharina latissima and the red Mastocarpus stellatus, respectively. Although distribution of molecular weight was broad, the good repeatability for retention time provided a good precision in MW estimation of polysaccharides. Water- and alkali-soluble fractions from S. latissima ranged from very high (>2400 kDa) to low MW compounds (<6 kDa); this high

Breast Massage, Implant Displacement, and Prevention of Capsular Contracture After Breast Augmentation With Implants: A Review of the Literature.

PubMed

Sood, Aditya; Xue, Erica Y; Sangiovanni, Christopher; Therattil, Paul J; Lee, Edward S

2017-01-01

Objective: Capsular contracture, the most common complication following breast augmentation with implants, is a complex inflammatory reaction that ultimately leads to fibrosis at the contact site between the implant and tissue. A number of peri-, pre-, and postoperative techniques have been postulated and implemented by many surgeons to reduce the incidence of capsular contracture. Breast massage and implant displacement technique is a commonly recommended practice that has not been well studied in regard to capsular contracture prevention. The authors present a review of the literature addressing methods and efficacy of massage and implant displacement techniques after breast augmentation. Methods: A literature review was performed using PubMed and the Cochrane Collaboration Library for primary research articles on breast massage or implant displacement after breast augmentation with implants for breast contracture prevention between January 1975 and March 2017. Exclusion criteria were studies that were focused on the treatment rather than prevention of breast contracture, addressed other strategies of preventing contracture as the main focus, or did not report the number of patients studied. Information related to massage technique and capsular contracture outcomes was extracted. Results: The literature search yielded 4 relevant studies, with a total of 587 patients. Outcomes evaluated included massage technique, onset of massage, frequency of massage, and incidence of capsular contracture. Breast massage was introduced between 2 days and 2 weeks postoperatively, performed twice daily, and lasted from 2 to 5 minutes for each breast. Final postoperative follow-up concluded between 6 and 36 months. The average capsular contracture rate was similar, 31% (range, 0-35) in the massage group versus 40% (range, 30-90) in the nonmassage group. Conclusions: While multiple techniques have been proposed and practiced in the prevention of capsular contracture, breast massage

Antioxidant and anticoagulant activity of sulfated polysaccharide from Gracilaria debilis (Forsskal).

PubMed

Sudharsan, Sadhasivam; Subhapradha, Namasivayam; Seedevi, Palaniappan; Shanmugam, Vairamani; Madeswaran, Perumal; Shanmugam, Annaian; Srinivasan, Alagiri

2015-11-01

Sulfated polysaccharide was isolated from Gracilaria debilis and purified through gel chromatography and their molecular weight was determined through AGE and PAGE. The total sugars in the crude, fractionated and purified polysaccharide were estimated as 52.65%, 59.70% and 67.60%, respectively. The ash and moisture content of crude and purified polysaccharide was found to be 14.2% and 23.5% and the polysaccharide was free from protein contamination. The sulfate and uronic acid contents in the crude, fractionated and purified were estimated as 14.08%, 15.33% and 16.01% and 10.12%, 13.56%, 16.70%. The elemental composition including carbon (crude - 23.12%, purified - 21.05%), hydrogen (crude - 3.4%, purified - 4.13%) and nitrogen (crude - 1.22%, purified - 0.56%) were also analyzed. The anticoagulant activity of the sulfated polysaccharide through APTT and PT was estimated at 14.11 and 8.23IU/mg. The purified polysaccharide with the molecular mass of 20kDa showed highest antioxidant activity (38.57%, 43.48% and 38.88%) in all the assays tested such as DPPH hydroxyl radical, superoxide radical, hydroxyl radical scavenging activities and the structural property was analyzed through FT-IR and (1)H NMR spectrum. The results together suggest that the isolated low molecular weight sulfated polysaccharide will demonstrate as a enormously available alternative natural source of antioxidant for industrial uses. Copyright © 2015 Elsevier B.V. All rights reserved.

Genomic Diversity of Burkholderia pseudomallei Clinical Isolates: Subtractive Hybridization Reveals a Burkholderia mallei-Specific Propage in B. pseudomallei 1026b

DTIC Science & Technology

2004-06-01

identification of several new virulence gene candidates. In particular, K96243 harbors multiple genomic islands with relatively low GC contents, suggesting...coli, Streptococcus pyogenes, Staphylococcus aureus, S. enterica, and Xylella fastidiosa (11, 16, 17). The genomic sequencing results for multiple... virulence genes by subtractive hybridization: identifica- tion of capsular polysaccharide of Burkholderia pseudomallei as a major virulence determinant

Role of natural polysaccharides in radiation formation of PVA hydrogel wound dressing

NASA Astrophysics Data System (ADS)

Varshney, Lalit

2007-02-01

Radiation processed PVA-polysaccharides hydrogels have been observed to be suitable for producing transparent, flexible, mechanically strong, biocompatible, effective and economical hydrogel dressings. The dressings were formed in single stage irradiation process achieving gel formation and sterilization at 25-30 kGy gamma radiation dose. No synthetic plasticizers and additives were used. Different formulations containing poly-vinylalcohol (PVA) and polysaccharides selected from combinations of agar and carrageenan were used to make the dressings. The selected polysaccharides themselves form thermo-reversible gels and degrade on irradiation. Using concentration of polysaccharides as low as 0.5-2% resulted in increase of tensile strength from 45 g/cm 2 to 411 g/cm 2, elongation from 30% to 410% and water uptake from 25% to 157% with respect to PVA gel without polysaccharides. Besides improving mechanical strength, agar contributes more to elongation and carrageenan to mechanical strength of the gel dressing. PVA formulations containing the polysaccharides show significantly different pre-gel viscosities behaviour. Increasing the concentration of agar in the formulation to about 2% converts the sheet gel to paste gel useful for filling wound cavities. The results indicate that pre irradiation network structure of the formulation plays an important role in determining mechanical properties of the irradiated gel dressing. Formulations containing 7-9% PVA, 0.5-1.5% carrageenan and 0.5-1% agar gave highly effective usable hydrogel dressings. Scanning electron micrographs show highly porous structure of the gel. Clinical trials of wound dressing on human patients established safety and efficacy of the dressing. The dressing has been observed to be useful in treating burns, non-healing ulcers of diabetes, leprosy and other external wounds. The dressings are now being marketed in India under different brand names.

The Selenylation Modification of Epimedium Polysaccharide and Isatis Root Polysaccharide and the Immune-enhancing Activity Comparison of Their Modifiers.

PubMed

Li, Xiuping; Hou, Ranran; Yue, Chanjuan; Liu, Jie; Gao, Zhenzhen; Chen, Jin; Lu, Yu; Wang, Deyun; Liu, Cui; Hu, Yuanliang

2016-05-01

Epimedium polysaccharide (EPS) and isatis root polysaccharide (IRPS) were extracted, purified, and selenizingly modified by nitric acid-sodium selenite method to obtain nine selenizing EPSs (sEPSs), sEPS1-sEPS9 and nine selenizing IRPSs (sIRPSs), sIRPS1-sIRPS9, respectively. Their effects on chicken peripheral lymphocyte proliferation in vitro were compared by MTT assay. The results showed that selenium polysaccharides at appropriate concentration could promote lymphocyte proliferation more significantly than unmodified polysaccharides, sEPS5 and sIRPS5 with stronger actions were picked out and injected into the chickens vaccinated with Newcastle disease vaccine in vivo tests. The peripheral lymphocyte proliferation and serum antibody titer were determined. The results showed that sEPS5 and sIRPS5 could elevate serum antibody titer and promote lymphocyte proliferation more significantly than unmodified polysaccharides, sEPS5 possessed the strongest efficacy. These results indicate that selenylation modification can significantly enhance the immune-enhancing activity of EPS and IRPS, and sEPS5 can be as a new-type immunopotentiator of chickens.

Combined Therapy with Rheum tanguticum Polysaccharide and Low-dose 5-ASA Ameliorates TNBS-Induced Colitis in Rats by Suppression of NF-κB.

PubMed

Liu, Linna; Liu, Zhenxiong; Zhang, Tian; Shi, Lei; Zhang, Wenjuan; Zhang, Yan

2015-06-01

The most common conventional therapy for inflammatory bowel disease in clinical practice involves the use of nonsteroidal anti-inflammatory drugs, such as 5-amino salicylic acid. However, a high dose of 5-amino salicylic acid may bring about severe side effects. Chinese people have used Rheum tanguticum as a folk remedy for gastrointestinal disease for two thousand years. Our group has isolated R. tanguticum polysaccharide 1 from R. tanguticum and verified that it can attenuate 2,4,6-trinitrobenzene sulfonic acid-induced colitis in murines/rats. The present study aims to evaluate whether the addition of R. tanguticum polysaccharide 1 can improve efficacy and limit subsequent side effects of conventional treatment (5-amino salicylic acid) in rats with 2,4,6-trinitrobenzene sulfonic acid-induced colitis. Sixty Sprague-Dawley male rats were randomized into five groups and treated with (1) saline (saline, 0.2 mL/day × 5, p. o.), (2) 2,4,6-trinitrobenzene sulfonic acid alone (saline, 0.2 mL/day × 5, p. o.), (3) 2,4,6-trinitrobenzene sulfonic acid + 5-amino salicylic acid (5-amino salicylic acid, 75 mg/kg/day × 5, p.o), (4) 2,4,6-trinitrobenzene sulfonic acid + R. tanguticum polysaccharide 1 (R. tanguticum polysaccharide 1, 200 mg/kg/day × 5, p. o.), and (5) 2,4,6-trinitrobenzene sulfonic acid + 5-amino salicylic acid + R. tanguticum polysaccharide 1 (5-amino salicylic acid, 25 mg/kg/day × 5, p.o; R. tanguticum polysaccharide 1, 200 mg/kg/day × 5, p. o.). All the rats were sacrificed on the 6th day after treatment using an overdose of anesthesia. A histological assessment was performed using semiquantitative scores; nuclear factor-kappa B and tumor necrosis factor-α were measured with Western blot, cyclooxygenase 1 and cyclooxygenase 2 protein expressions were investigated by RT-polymerase chain reaction, and prostoglandin E2 and inducible nitric oxide synthase productions were investigated by ELISA. The extent and

Preparation of low molecular weight Sargassum fusiforme polysaccharide and its anticoagulant activity

NASA Astrophysics Data System (ADS)

Sun, Yuhao; Chen, Xiaolin; Liu, Song; Yu, Huahua; Li, Rongfeng; Wang, Xueqin; Qin, Yukun; Li, Pengcheng

2017-10-01

Heparin has been used as an anticoagulant drug for many years, but it has significant side effects. In the search for good substitutes, low molecular weight (MW) polysaccharides from Sargassum fusiforme have been examined and confirmed to possess biological activities. Here, S. fusiforme polysaccharides (SFP) were extracted and subjected to a hydrogen peroxide (H2O2) oxidation method for the preparation of low-MW SFP (LSFP). The effects of temperature, pH, and H2O2 concentration on the degradation process were also examined. Several LSFP of 36, 9, 5.7, and 2.7 kDa were obtained under different conditions, and their anticoagulant activities studied in vitro. The results showed that SFP and LSFP prolonged activated partial thromboplastin (APTT), prothrombin (PT) and thrombin times (TT) significantly, indicating that these low MW polysaccharides possessed anticoagulant activity in the intrinsic, extrinsic, and common coagulation pathways. As these effects were related to the MW of the polysaccharides in APTT and TT but not in PT, the contents of the monosaccharide fucose and sulfate and the polysaccharide MW could have exerted combined effects. The details of this mechanism require further verification.

Phospholipids Trigger Cryptococcus neoformans Capsular Enlargement during Interactions with Amoebae and Macrophages

PubMed Central

Chrisman, Cara J.; Albuquerque, Patricia; Guimaraes, Allan J.; Nieves, Edward; Casadevall, Arturo

2011-01-01

A remarkable aspect of the interaction of Cryptococcus neoformans with mammalian hosts is a consistent increase in capsule volume. Given that many aspects of the interaction of C. neoformans with macrophages are also observed with amoebae, we hypothesized that the capsule enlargement phenomenon also had a protozoan parallel. Incubation of C. neoformans with Acanthamoeba castellanii resulted in C. neoformans capsular enlargement. The phenomenon required contact between fungal and protozoan cells but did not require amoeba viability. Analysis of amoebae extracts showed that the likely stimuli for capsule enlargement were protozoan polar lipids. Extracts from macrophages and mammalian serum also triggered cryptococcal capsular enlargement. C. neoformans capsule enlargement required expression of fungal phospholipase B, but not phospholipase C. Purified phospholipids, in particular, phosphatidylcholine, and derived molecules triggered capsular enlargement with the subsequent formation of giant cells. These results implicate phospholipids as a trigger for both C. neoformans capsule enlargement in vivo and exopolysaccharide production. The observation that the incubation of C. neoformans with phospholipids led to the formation of giant cells provides the means to generate these enigmatic cells in vitro. Protozoan- or mammalian-derived polar lipids could represent a danger signal for C. neoformans that triggers capsular enlargement as a non-specific defense mechanism against potential predatory cells. Hence, phospholipids are the first host-derived molecules identified to trigger capsular enlargement. The parallels apparent in the capsular response of C. neoformans to both amoebae and macrophages provide additional support for the notion that certain aspects of cryptococcal virulence emerged as a consequence of environmental interactions with other microorganisms such as protists. PMID:21637814

Macrophage immunomodulatory activity of polysaccharides isolated from Opuntia polyacantha

PubMed Central

Schepetkin, Igor A.; Xie, Gang; Kirpotina, Liliya N.; Klein, Robyn A.; Jutila, Mark A.; Quinn, Mark T.

2008-01-01

Opuntia polyacantha (prickly pear cactus) has been used extensively for its nutritional properties; however, less is known regarding medicinal properties of Opuntia tissues. In the present study, we extracted polysaccharides from O. polyacantha and used size-exclusion chromatography to fractionate the crude polysaccharides into four polysaccharide fractions (designated as Opuntia polysaccharides C-I to C-IV). The average Mr of fractions C-I through C-IV was estimated to be 733, 550, 310, and 168 kDa, respectively, and sugar composition analysis revealed that Opuntia polysaccharides consisted primarily of galactose, galacturonic acid, xylose, arabinose, and rhamnose. Analysis of the effects of Opuntia polysaccharides on human and murine macrophages demonstrated that all four fractions had potent immunomodulatory activity, inducing production of reactive oxygen species, nitric oxide, tumor necrosis factor α, and interleukin 6. Furthermore, modulation of macrophage function by Opuntia polysaccharides was mediated, at least in part, through activation of nuclear factor κB. Together, our results provide a molecular basis to explain a portion of the beneficial therapeutic properties of extracts from O. polyacantha and support the concept of using Opuntia polysaccharides as an immunotherapeutic adjuvant. PMID:18597716

A Salmonella Typhimurium-Typhi Genomic Chimera: A Model to Study Vi Polysaccharide Capsule Function In Vivo

PubMed Central

Clare, Simon; Goulding, David; Holt, Kathryn E.; Grant, Andrew J.; Mastroeni, Piero; Dougan, Gordon; Kingsley, Robert A.

2011-01-01

The Vi capsular polysaccharide is a virulence-associated factor expressed by Salmonella enterica serotype Typhi but absent from virtually all other Salmonella serotypes. In order to study this determinant in vivo, we characterised a Vi-positive S. Typhimurium (C5.507 Vi+), harbouring the Salmonella pathogenicity island (SPI)-7, which encodes the Vi locus. S. Typhimurium C5.507 Vi+ colonised and persisted in mice at similar levels compared to the parent strain, S. Typhimurium C5. However, the innate immune response to infection with C5.507 Vi+ and SGB1, an isogenic derivative not expressing Vi, differed markedly. Infection with C5.507 Vi+ resulted in a significant reduction in cellular trafficking of innate immune cells, including PMN and NK cells, compared to SGB1 Vi− infected animals. C5.507 Vi+ infection stimulated reduced numbers of TNF-α, MIP-2 and perforin producing cells compared to SGB1 Vi−. The modulating effect associated with Vi was not observed in MyD88−/− and was reduced in TLR4−/− mice. The presence of the Vi capsule also correlated with induction of the anti-inflammatory cytokine IL-10 in vivo, a factor that impacted on chemotaxis and the activation of immune cells in vitro. PMID:21829346

Klebsiella capsular type versus site of isolation.

PubMed Central

Riser, E; Noone, P

1981-01-01

More than 1750 clinical isolates of klebsiella were collected over a period of six years from two different hospitals and capsular typed by the fluorescent antibody technique. A correlation was made between type and site of isolation. Many types were found to be associated more frequently with one site, which suggested a predilection of some capsular types for certain sites of infection. The site may also be a factor contributing to the virulence of a particular type. A greater antibiotic resistance was often noted in types isolated from their predominant sites; however, antibiograms were not consistent for a type from a given site. The combination of site specificity, resistance, and another 'virulence factor' may all be involved in the determination of a pathogenic strain. PMID:7251896

Survival and interaction of Escherichia coli O104:H4 on Arabidopsis thaliana and lettuce (Lactuca sativa) in comparison to E. coli O157:H7: Influence of plant defense response and bacterial capsular polysaccharide.

PubMed

Jang, Hyein; Matthews, Karl R

2018-06-01

Shiga toxin-producing Escherichia coli (STEC) has been associated with illnesses and outbreaks linked to fresh vegetables, prompting a growing public health concern. Most studies regarding interactions of STEC on fresh produce focused on E. coli O157:H7. Limited information is available about survival or fitness of E. coli O104:H4, non-O157 pathogen that was linked to one of the largest outbreaks of hemolytic uremic syndrome in 2011. In this study, survival of E. coli O104:H4 was evaluated on Arabidopsis thaliana plant and lettuce for 5 days compared with E. coli O157:H7, and expression of pathogenesis-realted gene (PR1; induction of plant defense response) was examined by reverse transcription quantitative PCR, and potential influence of capsular polysaccharide (CPS) on the bacterial fitness on plant was investigated. Populations of E. coli O104:H4 strains (RG1, C3493, and LpfA) on Arabidopsis and lettuce were significantly (P < 0.05) greater than those of E. coli O157:H7 strains (7386 and sakai) at day 5 post-inoculation, indicating E. coli O104:H4 may have better survival ability on the plants. In addition, the E. coli O104:H4 strains produced significantly (P < 0.05) higher amounts of CPS compared with the E. coli O157:H7 strains. RG1 strain (1.5-fold) initiated significantly (P < 0.05) lower expression of PR1 gene indicating induction of plant defense response compared with E. coli O157:H7 strains 7386 (2.9-fold) and sakai (2.7-fold). Collectively, the results in this study suggests that different level of CPS production and plant defense response initiated by each STEC strain might influence the bacterial survival or persistence on plants. The present study provides better understanding of survival behavior of STEC, particularly E. coli O104:H4, using a model plant and vegetable under pre-harvest conditions with plant defense response. Copyright © 2018 Elsevier Ltd. All rights reserved.

Interaction of antimicrobial peptides with bacterial polysaccharides from lung pathogens.

PubMed

Herasimenka, Yury; Benincasa, Monica; Mattiuzzo, Maura; Cescutti, Paola; Gennaro, Renato; Rizzo, Roberto

2005-07-01

The interaction of two cathelicidin antimicrobial peptides, LL-37 and SMAP-29, with three bacterial polysaccharides, respectively, produced by Pseudomonas aeruginosa, Burkholderia cepacia and Klebsiella pneumoniae, was investigated to identify possible mechanisms adopted by lung pathogens to escape the action of innate immunity effectors. In vitro assays indicated that the antibacterial activity of both peptides was inhibited to a variable extent by the three polysaccharides. Circular dichroism experiments showed that these induced an alpha-helical conformation in the two peptides, with the polysaccharides from K. pneumoniae and B. cepacia showing, respectively, the highest and the lowest effect. Fluorescence measurements also indicated the presence of peptide-polysaccharide interactions. A model is proposed in which the binding of peptides to the polysaccharide molecules induces, at low polysaccharide to peptide ratios, a higher order of aggregation, due to peptide-peptide interactions. Overall, these results suggest that binding of the peptides by the polysaccharides produced by lung pathogens can contribute to the impairment of peptide-based innate defenses of airway surface.

Pectic polysaccharides from Panax ginseng as the antirotavirus principals in ginseng.

PubMed

Baek, Seung-Hoon; Lee, Jin Gyun; Park, Seo Young; Bae, Ok Nam; Kim, Dong-Hyun; Park, Jeong Hill

2010-08-09

To evaluate the antidiarrheal effect of ginseng, the active principals of ginseng were studied in vitro model of rotavirus infection, the leading cause of severe diarrhea. Two pectic polysaccharides, named as GP50-dHR (56.0 kDa) and GP50-eHR (77.0 kDa), were purified from hot water extract of ginseng by bioassay-linked fractionation. Both polysaccharides rescued cell viability from rotavirus infection dose-dependently (IC50 are 15 and 10 microg/mL, respectively). Both polysaccharides had common structural features of homogalacturonan backbone with hairy regions of rhamnogalacturonan type I. Arabinose-rich side chains with abundant branch points were unique in GP50-eHR and may contribute to a greater antirotavirus effect of GP50-eHR than GP50-dHR. Because homogalacturonan itself did not show an antirotavirus effect, hairy regions might be functional sites. Of note, the antirotavirus effect of both polysaccharides resulted from inhibiting rotavirus attachment to cells. Together with a wide range of noncytotoxicity, these findings suggest that ginseng polysaccharides are viable therapeutic options for rotavirus diarrhea.

A Monoclonal Antibody to Cryptococcus neoformans Glucuronoxylomannan Manifests Hydrolytic Activity for Both Peptides and Polysaccharides*

PubMed Central

Wear, Maggie P.; Cordero, Radames J. B.; Oscarson, Stefan

2017-01-01

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. PMID:27872188

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. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Capture of intraocular lens optic by residual capsular opening in secondary implantation: long-term follow-up.

PubMed

Tian, Tian; Chen, Chunli; Jin, Haiying; Jiao, Lyu; Zhang, Qi; Zhao, Peiquan

2018-04-02

To introduce a novel surgical technique for optic capture by residual capsular opening in secondary intraocular lens (IOL) implantation and to report the outcomes of a long follow-up. Twenty patients (20 eyes) who had received secondary IOL implantation with the optic capture technique were retrospectively reviewed. We used the residual capsular opening for capturing the optic and inserted the haptics in the sulcus during surgery. Baseline clinical characteristics and surgical outcomes, including best-corrected visual acuity (BCVA), refractive status, and IOL position were recorded. The postoperative location and stability of IOL were evaluated using the ultrasound biomicroscopy. Optic capture technique was successfully performed in all cases, including 5 cases with large area of posterior capsular opacity, 6 cases with posterior capsular tear or rupture,and 9 cases with adhesive capsules. BCVA improved from 0.60 logMAR at baseline to 0.36 logMAR at the last follow-up (P < 0.001). Spherical equivalent changed from 10.67 ± 4.59 D at baseline to 0.12 ± 1.35 D at 6 months postoperatively (P < 0.001). Centered IOLs were observed in all cases and remained captured through residual capsular opening in 19 (95%) eyes at the last follow-up. In one case, the captured optic of IOL slid into ciliary sulcus at 7 months postoperatively. No other postoperative complications were observed in any cases. This optic capture technique by using residual capsule opening is an efficacious and safe technique and can achieve IOL stability in the long follow-up.

Capsules from pathogenic and non-pathogenic Cryptococcus spp. manifest significant differences in structure and ability to protect against phagocytic cells.

PubMed

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; Souza, Wanderley de; 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

Characterization and hypoglycemic activity of a β-pyran polysaccharides from bamboo shoot (Leleba oldhami Nakal) shells.

PubMed

Zheng, Yafeng; Zhang, Shuai; Wang, Qi; Lu, Xu; Lin, Liangmei; Tian, Yuting; Xiao, Jianbo; Zheng, Baodong

2016-06-25

The bamboo shoot (Leleba oldhami Nakal) shell is a by-product during bamboo shoot processing. It is a cheap and available resource for dietary polysaccharides. Herein, a novel polysaccharide BSSP2a was isolated and characterized from the bamboo shoot shell polysaccharides, and it was identified as a homogeneous highly-branched beta type pyran polysaccharide with a molecular weight of 1.63×10(4)kDa, which consisted of arabinose, xylose, mannose, glucose and galactose at a molar ratio of 20.4:4.9:1:3.4:20.6. The crude polysaccharides (BSSP) from the bamboo shoots shell showed hypoglycemic activity on the high fat diet and streptozotocin induced diabetic mice in a dose-dependent manner. The administration of high dose BSSP (400mg/kg) improved body weight loss and serum insulin loss, and significantly decreased the blood glucose level, serum triglycerides as well as total cholesterol levels by 48.7%, 34.8% and 26.5%, respectively. The results highlight the potential of the bamboo shoot shell polysaccharides as a natural anti-diabetic agent. Copyright © 2016 Elsevier Ltd. All rights reserved.

In vitro fermentation of sulfated polysaccharides from E. prolifera and L. japonica by human fecal microbiota.

PubMed

Kong, Qing; Dong, Shiyuan; Gao, Jian; Jiang, Chaoyu

2016-10-01

In vitro fermentation of the sulfated polysaccharides from seaweeds Enteromorpha prolifera and Laminaria japonica and their prebiotic effects on human fecal microbiota were investigated in this study. The sulfated polysaccharides were fermented in vitro for 48h by human fecal cultures. When 0.8g MWCOL (polysaccharides MWCO<30kD) from L. japonica was fermented, the pH in fecal cultures decreased from 6.5 to 5.1 and the levels of short chain fatty acids, such as acetic, butyric and lactic acids all significantly increased. After 48h fermentation, 0.8g MWCOL showed good effect on modulating the gut microflora balance, because the beneficial strains (Lactobacillus and Bifidobacterium) were both significantly higher than those in control group (p<0.05). As far as we know, this is the first report that consumption of sulfated polysaccharides from E. prolifera and L. japonica is beneficial to the ecosystem of the intestinal tract by increasing the populations of probiotics and short chain fatty acids. Furthermore, our reports indicated that molecular weight of sulfated polysaccharide from marine algae is related to its prebiotic effects. Copyright © 2016 Elsevier B.V. All rights reserved.

FT-IR study of the polysaccharides isolated from the skin juice, gel juice, and flower of Aloe vera tissues affected by fertilizer treatment

PubMed Central

2012-01-01

Background This experiment was conducted to evaluate the effect of different amounts of fertilizers on the polysaccharides of Aloe vera plant. There were four different treatments, viz. T1 = 150% N, T2 = 150% P, T3 = 150% K, and T4 = 150% NPK (50% N + 50% P + 50% K) soil. Crude water-soluble polysaccharides were isolated from the gel juice, skin juice, and flowers of A. vera planted in these soils. Results Result indicates that skin juice contained 2.4 times the level of polysaccharides in gel juice from one plant, suggesting the potential industrial application of A. vera skin rather than discarding it. After anion-exchange chromatography, neutral polysaccharides accounted for 58.1% and 78.5% of the total recovered neutral and acidic polysaccharide preparations from the gel juice and skin juice, respectively, whereas the crude flower polysaccharides were largely composed of weakly acidic polysaccharides (84.2%). Sugar analysis of the polysaccharides after gel permeation chromatography revealed that glucose and galactose were the most abundant monosaccharide in the neutral polysaccharides from the gel juice and skin juice, respectively. The acidic polysaccharides from the two juices consisted of glucuronic acid, galactose, glucose, mannose, and xylose with variable proportions. Conclusions Except glucuronic acid (15.4%) in flower acidic polysaccharide, the flower neutral and acidic polysaccharides contained galactose, glucose, and mannose as the main sugar components. Glucuronic acid was the major uronic acid in all acidic polysaccharides from different tissues. PMID:23095284

Capsular Outcomes After Pediatric Cataract Surgery Without Intraocular Lens Implantation

PubMed Central

Tan, Xuhua; Lin, Haotian; Lin, Zhuoling; Chen, Jingjing; Tang, Xiangchen; Luo, Lixia; Chen, Weirong; Liu, Yizhi

2016-01-01

Abstract The objective of this study was to investigate capsular outcomes 12 months after pediatric cataract surgery without intraocular lens implantation via qualitative classification and quantitative measurement. This study is a cross-sectional study that was approved by the institutional review board of Zhongshan Ophthalmic Center of Sun Yat-sen University in Guangzhou, China. Digital coaxial retro-illumination photographs of 329 aphakic pediatric eyes were obtained 12 months after pediatric cataract surgery without intraocular lens implantation. Capsule digital coaxial retro-illumination photographs were divided as follows: anterior capsule opening area (ACOA), posterior capsule opening area (PCOA), and posterior capsule opening opacity (PCOO). Capsular outcomes were qualitatively classified into 3 types based on the PCOO: Type I—capsule with mild opacification but no invasion into the capsule opening; Type II—capsule with moderate opacification accompanied by contraction of the ACOA and invasion to the occluding part of the PCOA; and Type III—capsule with severe opacification accompanied by total occlusion of the PCOA. Software was developed to quantitatively measure the ACOA, PCOA, and PCOO using standardized DCRPs. The relationships between the accurate intraoperative anterior and posterior capsulorhexis sizes and the qualitative capsular types were statistically analyzed. The DCRPs of 315 aphakic eyes (95.8%) of 191 children were included. Capsular outcomes were classified into 3 types: Type I—120 eyes (38.1%); Type II—157 eyes (49.8%); Type III—38 eyes (12.1%). The scores of the capsular outcomes were negatively correlated with intraoperative anterior capsulorhexis size (R = −0.572, P < 0.001), but no significant correlation with intraoperative posterior capsulorhexis size (R = −0.16, P = 0.122) was observed. The ACOA significantly decreased from Type I to Type II to Type III, the PCOA increased in size from Type I to Type

On the chemical dynamics of extracellular polysaccharides in the high Arctic surface microlayer

NASA Astrophysics Data System (ADS)

Gao, Q.; Leck, C.; Rauschenberg, C.; Matrai, P. A.

2012-07-01

The surface microlayer (SML) represents a unique system of which the physicochemical characteristics may differ from those of the underlying subsurface seawater (SSW). Within the Arctic pack ice area, the SML has been characterized as enriched in small colloids of biological origin, resulting from extracellular polymeric secretions (EPS). During the Arctic Summer Cloud Ocean Study (ASCOS) in August 2008, particulate organic matter (POM, with size range > 0.22 μm) and dissolved organic matter (DOM, < 0.22 μm, obtained after filtration) samples were collected and chemically characterized from the SML and the corresponding SSW at an open lead centered at 87.5° N and 5° E. Total organic carbon was persistently enriched in the SML with a mean enrichment factor (EF) of 1.45 ± 0.41, whereas sporadic depletions of dissolved carbohydrates and amino acids were observed. Monosaccharide compositional analysis reveals that EPS in the Arctic lead was formed mainly of distinctive heteropolysaccharides, enriched in xylose, fucose and glucose. The mean concentrations of total hydrolysable neutral sugars in SSW were 94.9 ± 37.5 nM in high molecular weight (HMW) DOM (> 5 kDa) and 64.4 ± 14.5 nM in POM. The enrichment of polysaccharides in the SML appeared to be a common feature, with EFs ranging from 1.7 to 7.0 for particulate polysaccharides and 3.5 to 12.1 for polysaccharides in the HMW DOM fraction. A calculated monosaccharide yield suggests that polymers in the HMW DOM fraction were scavenged, without substantial degradation, into the SML. Bubble scavenging experiments showed that newly aggregated particles could be formed abiotically by coagulation of low molecular weight nanometer-sized gels. Aerosol particles, artificially generated by bubbling experiments, were enriched in polysaccharides by factors of 22-70, relative to the source seawater. We propose that bubble scavenging of surface-active polysaccharides could be one of the possible mechanisms for the enrichment of

The UDP-glucose dehydrogenase of Escherichia coli K-12 displays substrate inhibition by NAD that is relieved by nucleotide triphosphates.

PubMed

Mainprize, Iain L; Bean, Jordan D; Bouwman, Catrien; Kimber, Matthew S; Whitfield, Chris

2013-08-09

UDP-glucose dehydrogenase (Ugd) generates UDP-glucuronic acid, an important precursor for the production of many hexuronic acid-containing bacterial surface glycostructures. In Escherichia coli K-12, Ugd is important for biosynthesis of the environmentally regulated exopolysaccharide known as colanic acid, whereas in other E. coli isolates, the same enzyme is required for production of the constitutive group 1 capsular polysaccharides, which act as virulence determinants. Recent studies have implicated tyrosine phosphorylation in the activation of Ugd from E. coli K-12, although it is not known if this is a feature shared by bacterial Ugd proteins. The activities of Ugd from E. coli K-12 and from the group 1 capsule prototype (serotype K30) were compared. Surprisingly, for both enzymes, site-directed Tyr → Phe mutants affecting the previously proposed phosphorylation site retained similar kinetic properties to the wild-type protein. Purified Ugd from E. coli K-12 had significant levels of NAD substrate inhibition, which could be alleviated by the addition of ATP and several other nucleotide triphosphates. Mutations in a previously identified UDP-glucuronic acid allosteric binding site decreased the binding affinity of the nucleotide triphosphate. Ugd from E. coli serotype K30 was not inhibited by NAD, but its activity still increased in the presence of ATP.

Organization of the Escherichia coli K-12 gene cluster responsible for production of the extracellular polysaccharide colanic acid.

PubMed Central

Stevenson, G; Andrianopoulos, K; Hobbs, M; Reeves, P R

1996-01-01

Colanic acid (CA) is an extracellular polysaccharide produced by most Escherichia coli strains as well as by other species of the family Enterobacteriaceae. We have determined the sequence of a 23-kb segment of the E. coli K-12 chromosome which includes the cluster of genes necessary for production of CA. The CA cluster comprises 19 genes. Two other sequenced genes (orf1.3 and galF), which are situated between the CA cluster and the O-antigen cluster, were shown to be unnecessary for CA production. The CA cluster includes genes for synthesis of GDP-L-fucose, one of the precursors of CA, and the gene for one of the enzymes in this pathway (GDP-D-mannose 4,6-dehydratase) was identified by biochemical assay. Six of the inferred proteins show sequence similarity to glycosyl transferases, and two others have sequence similarity to acetyl transferases. Another gene (wzx) is predicted to encode a protein with multiple transmembrane segments and may function in export of the CA repeat unit from the cytoplasm into the periplasm in a process analogous to O-unit export. The first three genes of the cluster are predicted to encode an outer membrane lipoprotein, a phosphatase, and an inner membrane protein with an ATP-binding domain. Since homologs of these genes are found in other extracellular polysaccharide gene clusters, they may have a common function, such as export of polysaccharide from the cell. PMID:8759852

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.

Extraction Optimization, Purification and Physicochemical Properties of Polysaccharides from Gynura medica.

PubMed

Li, Fengwei; Gao, Jian; Xue, Feng; Yu, Xiaohong; Shao, Tao

2016-03-23

Extraction of polysaccharides from Gynura medica (GMPs) was optimized by response surface methodology (RSM). A central composition design including three parameters, namely extraction temperature (X₁), ratio of water to raw material (X₂) and extraction time (X₃), was used. The best conditions were extraction temperature of 91.7 °C, extraction time of 4.06 h and ratio of water to raw material of 29.1 mL/g. Under the optimized conditions, the yield of GMPs was 5.56%, which was similar to the predicted polysaccharides yield of 5.66%. A fraction named GMP-1 was obtained after isolation and purification by DEAE-52 and Sephadex G-100 gel chromatography, respectively. GMP-1, with a molecular weight of 401 kDa, mainly consisted of galacturonic acid (GalA), xylose (Xyl), glucose (Glu). Infrared spectroscopy was used to characterize the major functional groups of GMP-1 and the results indicated that it was an acidic polysaccharide. The antioxidant and α-glucosidase inhibitory activities of GMPs and GMP-1 were determined in vitro. The results indicated that GMPs and GMP-1 show potential for use in functional foods or medicines.

Treatment of experimental Escherichia coli infection with recombinant bacteriophage-derived capsule depolymerase.

PubMed

Mushtaq, Naseem; Redpath, Maria B; Luzio, J Paul; Taylor, Peter W

2005-07-01

The aim of this study was to investigate the effect of single doses of the capsule depolymerizing enzyme endosialidase E (endoE) on the course of systemic infection due to Escherichia coli K1 strains in neonatal rats. We also determined the capacity of the enzyme to increase the sensitivity of K1 strains to rat peritoneal macrophages. Bacteraemia was established in Wistar rats by induction of gastrointestinal colonization with the virulent K1 strain A192PP; colonization preceded a lethal bacteraemia. Decreasing single doses of endoE were administered intraperitoneally. Macrophage engulfment of K1 strain A192PP was evaluated by staining and microscopy in the presence and absence of endoE. A192PP colonized the gastrointestinal tract of all 2-day-old animals and produced bacteraemia in over 90%. A single endoE dose of 0.25 microg curtailed bacteraemia and prevented death in at least 80% of infected animals. Older animals (up to 5 days of age) were less susceptible to systemic infection following intestinal colonization. EndoE-mediated removal of K1 capsular polysaccharide led to increased ingestion by macrophages. A small single dose of capsule-depolymerizing enzyme has therapeutic utility in lethal systemic infection in a non-invasive model that has characteristics of the infectious process in humans. We propose that the enzyme reduces the virulence of E. coli K1 by rapid removal of the protective capsular polysaccharide, sensitizing the pathogen to host defences such as phagocytosis by macrophages. Thus, whilst endoE-mediated therapy may not be a viable approach to the treatment of systemic infection in humans, it does support the concept that alteration of the cell wall phenotype is a valid therapeutic strategy.

Screening and comparison of antioxidant activities of polysaccharides from Coriolus versicolor.

PubMed

Sun, Xiaowen; Sun, Yanping; Zhang, Qingbo; Zhang, Hongwei; Yang, Bingyou; Wang, Zhibin; Zhu, Weiguo; Li, Bin; Wang, Qiuhong; Kuang, Haixue

2014-08-01

Six polysaccharide fractions (Coriolus versicolor polysaccharides: CVPS-1, CVPS-2, CVPS-3, CVPS-4, CVPS-5 and CVPS-6) were isolated and purified from the fruiting bodies of C. versicolor by ion exchange chromatography and gel chromatography. Their chemical and physical characteristics were determined by chemical methods, high performance liquid chromatography, and high-performance gel-permeation chromatography. Finally, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assay, superoxide radical assay, and hydroxyl radical assay were carried out to test the antioxidant activities of CVPS in vitro. The results indicated that the six CVPS fractions were acidic heteropolysaccharides, composed of mannose, rhamnose, glucuronic acid, glucose and fructose with different ratios. The molecular weights of CVPS-1, CVPS-2, CVPS-3, CVPS-4, CVPS-5 and CVPS-6 were 1740, 1480, 568, 880, 1260 and 1840kDa and the protein contents were 4.2%, 6.4%, 8.5%, 7.8%, 6.5% and 3.9%, respectively. Among the six fractions, CVPS with lower molecular weight, higher protein content and larger uronic acid amount, basically exhibited higher radical scavenging effects at the same concentration. Compared with other fractions, CVPS-3 exhibited the highest antioxidant activities. The effects of the molecular weight, protein content and uronic acid amount of the polysaccharides appeared to be significant on the improvement of the bioactivities. Copyright © 2014 Elsevier B.V. All rights reserved.

Immunomodulatory activity of polysaccharides isolated from Alchornea cordifolia

PubMed Central

Kouakou, Koffi; Schepetkin, Igor A.; Yapi, Ahoua; Kirpotina, Liliya N.; Jutila, Mark A.; Quinn, Mark T.

2013-01-01

Ethnopharmacological relevance Extracts of leaves from different species of the genus Alchornea have been used for centuries to treat a variety of medicinal problems in tropical Africa. However, little is known about the high-molecular weight active components conferring therapeutic properties to these extracts. Objective The aim of this study was to evaluate the immunomodulatory activity of polysaccharides isolated from the leaves of Alchornea cordifolia. Materials and methods Water-soluble polysaccharides from leaves of A. cordifolia were extracted and fractionated by DEAE-cellulose, Diaion HP-20, and size-exclusion chromatography. Molecular weight, sugar analysis, and other physical and chemical characterization of the fractions were performed. Immunomodulatory activity of the polysaccharide fractions was evaluated by determining their ability to induce monocyte/macrophage nitric oxide (NO) and cytokine production. Activation of mitogen activated protein kinases (MAPK) was also assessed using a phospho-MAPK array. Activation of nuclear factor κB (NF-κB) was measured using an alkaline phosphatase reporter gene assay in THP1-Blue monocytic cells. Results Six polysaccharide fractions from A. cordifolia were isolated. Fractions containing type II arabinogalactan had potent immunomodulatory activity. Particularly, the parent fraction AP-AU and its high-molecular weight sub-fraction AP-AU1 (average Mr was estimated to be 39.5 kDa) induced production of NO and cytokines [interleukin (IL)-1β, -6, -10, tumor necrosis factor (TNF)-α, and granulocyte macrophage-colony stimulating factor (GM-CSF)] in human peripheral blood mononuclear cells and human and murine monocyte/macrophages cell lines in vitro. Furthermore, treatment with AP-AU1 induced phosphorylation of Akt2, p38δ/p38γ, p70S6K1, RSK2, and mTOR, as well as stimulation of NF-κB transcriptional activity. Conclusion Our results provide a molecular basis to explain a portion of the beneficial therapeutic

Immunomodulatory activity of polysaccharides isolated from Alchornea cordifolia.

PubMed

Kouakou, Koffi; Schepetkin, Igor A; Yapi, Ahoua; Kirpotina, Liliya N; Jutila, Mark A; Quinn, Mark T

2013-03-07

Extracts of leaves from different species of the genus Alchornea have been used for centuries to treat a variety of medicinal problems in tropical Africa. However, little is known about the high-molecular weight active components conferring therapeutic properties to these extracts. The aim of this study was to evaluate the immunomodulatory activity of polysaccharides isolated from the leaves of Alchornea cordifolia. Water-soluble polysaccharides from leaves of Alchornea cordifolia were extracted and fractionated by DEAE-cellulose, Diaion HP-20, and size-exclusion chromatography. Molecular weight, sugar analysis, and other physical and chemical characterization of the fractions were performed. Immunomodulatory activity of the polysaccharide fractions was evaluated by determining their ability to induce monocyte/macrophage nitric oxide (NO) and cytokine production. Activation of mitogen activated protein kinases (MAPK) was also assessed using a phospho-MAPK array. Activation of nuclear factor κB (NF-κB) was measured using an alkaline phosphatase reporter gene assay in THP1-Blue monocytic cells. Six polysaccharide fractions from Alchornea cordifolia were isolated. Fractions containing type II arabinogalactan had potent immunomodulatory activity. Particularly, the parent fraction AP-AU and its high-molecular weight sub-fraction AP-AU1 (average M(r) was estimated to be 39.5kDa) induced production of NO and cytokines [interleukin (IL)-1β, -6, -10, tumor necrosis factor (TNF)-α, and granulocyte-macrophage-colony stimulating factor (GM-CSF)] in human peripheral blood mononuclear cells and human and murine monocyte/macrophages cell lines in vitro. Furthermore, treatment with AP-AU1 induced phosphorylation of Akt2, p38δ/p38γ, p70S6K1, RSK2, and mTOR, as well as stimulation of NF-κB transcriptional activity. Our results provide a molecular basis to explain a portion of the beneficial therapeutic properties of water extracts from Alchornea cordifolia leaves in

Extraction, characterization and antioxidant activities of Se-enriched tea polysaccharides.

PubMed

Wang, Yuanfeng; Li, Yongfu; Liu, Yangyang; Chen, Xueqing; Wei, Xinlin

2015-01-01

Se-polysaccharides from Se-enriched tea leaves were purified by DEAE-sepharose fast flow gel column (2.5×60cm) and three polysaccharide fractions (Se-TPS1, Se-TPS2, and Se-TPS3) were isolated and purified with yields of 6.5, 37.14, and 8.57%, respectively. The average sizes of Se-TPS1 and Se-TPS2 were determined by HPGPC system, with molecular weights of 1.1×10(5) and 2.4×10(5)Da, respectively. Se-TPS3 was a polysaccharide polymer with two peaks with molecular weights of 9.2×10(5) and 2.5×10(5)Da. Monosaccharide components analysis by ion chromatography revealed Se-polysaccharides were acidic polysaccharoses and different from each other in monosaccharide kinds and molar ratio. Elements of Se, C, H, N, S, and 14 kinds of mineral elements were analyzed by AFS, EA, and ICP-AES, respectively. Spectral analysis (IR and UV) indicated Se-polysaccharides were typical glycoproteins. Morphological analyses of the samples were determined by SEM and AFM. In addition, the DPPH and superoxide radicals scavenging activities were also discussed to assess antioxidant activities of the samples, and Se-polysaccharides showed higher antioxidant activities compared to the ordinary polysaccharides. Copyright © 2015 Elsevier B.V. All rights reserved.

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. Copyright © 2016 Elsevier Ltd. All rights reserved.

A comparative study of mucilage and pulp polysaccharides from tamarillo fruit (Solanum betaceum Cav.).

PubMed

do Nascimento, Georgia Erdmann; Iacomini, Marcello; Cordeiro, Lucimara M C

2016-07-01

A comparative study of mucilage (locular tissue) and pulp polysaccharides from ripe tamarillo fruits (Solanum betaceum Cav.) was carried out. After aqueous and alkaline extractions and various purification steps (freeze-thaw and α-amylase - EC 3.2.1.1 treatments, Fehling precipitation and ultrafiltration through 50 kDa cut-off membrane), the obtained fractions from mucilage were analyzed by sugar composition, HPSEC, and NMR spectroscopy analyses. The results showed that the mucilage of tamarillo contains a highly methoxylated homogalacturonans mixed with type I arabinogalactans, a linear (1 → 5)-linked α-L-arabinan, and a linear (1 → 4)-β-D-xylan. A comparison with polysaccharides extracted from the pulp revealed that differences were observed in the yield and in the ratio of extracted polysaccharides. Moreover, structural differences between pulp and mucilage polysaccharides were also observed, such as in the length of side chains of the pectins, and in the degree of branching of the xylans. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Transverse musculocutaneous gracilis flap for treatment of capsular contracture in tertiary breast reconstruction.

PubMed

Pülzl, Petra; Huemer, Georg M; Schoeller, Thomas

2015-02-01

Capsular contracture is a common complication associated with implant-based breast reconstruction and augmentation leading to pain, displacement, and rupture. After capsulectomy and implant exchange, the problem often reappears. We performed 52 deepithelialized free transverse musculocutaneous gracilis (TMG) flaps in 33 patients for tertiary breast reconstruction or augmentation of small- and medium-sized breasts. The indications for implant removal were unnatural feel and emotion of their breasts with foreign body feel, asymmetry, pain, and sensation of cold. Anyway, most of the patients did not have a severe capsular contracture deformity. The TMG flap is formed into a cone shape by bringing the tips of the ellipse together. Depending on the contralateral breast, the muscle can also be shaped in an S-form to get more projection if needed. The operating time for unilateral TMG flap breast reconstruction or augmentation was on average 3 hours and for bilateral procedure 5 hours. One patient had a secondary revision of the donor site due to disruption of the normal gluteal fold. Eighty percent of the unilateral TMG flap reconstructions had a lipofilling procedure afterward to correct small irregularities or asymmetry. The advantages of the TMG flap such as short harvesting time, inconspicuous donor site, and the possibility of having a natural breast shape make it our first choice to treat capsular contracture after breast reconstruction and augmentation.

Primary iris claw IOL retrofixation with intravitreal triamcinolone acetonide in cases of inadequate capsular support.

PubMed

Kelkar, Aditya; Shah, Rachana; Vasavda, Viraj; Kelkar, Jai; Kelkar, Shreekant

2018-02-01

To assess the outcomes and analyze complication rates following primary iris claw IOL retrofixation with intravitreal triamcinolone acetonide. This is a retrospective interventional case series. Patients with poor capsular support-diagnosed preoperatively or owing to intraoperative complications-were treated with iris claw IOL retrofixation with intravitreal triamcinolone acetonide. The data were retrospectively analyzed. 104 eyes of 102 patients with poor capsular support who underwent the procedure between 2010 and 2013 were analyzed. The minimum follow-up period was 12 months (ranging from 12 to 36 months). Iris claw IOL was implanted in-traumatic subluxated cataracts-24 cases (23.07%), non-traumatic subluxated cataracts in 16 cases (15.38%), or as a complication of cataract surgery-intraoperative posterior capsular rent in 48 cases (46.15%) and intraoperative nucleus drop in 16 cases (15.38%). The final mean best-corrected logMAR visual acuity improved from 1.36 ± 0.64 preoperatively to 0.36 ± 0.32 at 1-year follow-up. Complications included pupil ovalization in 11 cases (10.57%), transient elevation in intraocular pressure in 7 eyes (6.73%), postoperative hypotony in 5 eyes (4.80%), cystoid macular edema in 2 eyes (1.92%), retinal detachment in 1 eye (0.96%), vitreous hemorrhage in 1 eye (0.96%), and hyphema in 1 eye (0.96%). Primary iris claw IOL retrofixation provided excellent alternative in patients with inadequate capsular support. The visual outcomes were good along with favorable rates of complications. The addition of triamcinolone acetonide helps in reducing the chances of cystoid macular edema.

Surface Polysaccharide Mutants Reveal that Absence of O Antigen Reduces Biofilm Formation of Actinobacillus pleuropneumoniae

PubMed Central

Hathroubi, S.; Hancock, M. A.; Langford, P. R.; Tremblay, Y. D. N.; Labrie, J.

2015-01-01

Actinobacillus pleuropneumoniae is a Gram-negative bacterium belonging to the Pasteurellaceae family and the causative agent of porcine pleuropneumonia, a highly contagious lung disease causing important economic losses. Surface polysaccharides, including lipopolysaccharides (LPS) and capsular polysaccharides (CPS), are implicated in the adhesion and virulence of A. pleuropneumoniae, but their role in biofilm formation is still unclear. In this study, we investigated the requirement for these surface polysaccharides in biofilm formation by A. pleuropneumoniae serotype 1. Well-characterized mutants were used: an O-antigen LPS mutant, a truncated core LPS mutant with an intact O antigen, a capsule mutant, and a poly-N-acetylglucosamine (PGA) mutant. We compared the amount of biofilm produced by the parental strain and the isogenic mutants using static and dynamic systems. Compared to the findings for the biofilm of the parental or other strains, the biofilm of the O antigen and the PGA mutants was dramatically reduced, and it had less cell-associated PGA. Real-time PCR analyses revealed a significant reduction in the level of pgaA, cpxR, and cpxA mRNA in the biofilm cells of the O-antigen mutant compared to that in the biofilm cells of the parental strain. Specific binding between PGA and LPS was consistently detected by surface plasmon resonance, but the lack of O antigen did not abolish these interactions. In conclusion, the absence of the O antigen reduces the ability of A. pleuropneumoniae to form a biofilm, and this is associated with the reduced expression and production of PGA. PMID:26483403

Hypoglycemic Effect of Chinese Yam (Dioscorea opposita rhizoma) Polysaccharide in Different Structure and Molecular Weight.

PubMed

Li, Qian; Li, Wenzhi; Gao, Qunyu; Zou, Yuxiao

2017-10-01

Three new Chinese yam polysaccharides (namely HSY, huaishanyao in Chinese) were isolated using the methods of boiled water extraction and stepwise ethanolic precipitation, combined with the tangential flow ultrafiltration membrane system. Their molecular weights were determined by high performance gel permeation chromatography. Three type yam polysaccharides in different molecular weight were isolated: HSY-I (>50 kDa), HSY-II (10 to 50 kDa), HSY-III (<10 kDa). The monosaccharide and glycosidic bond links composition were analyzed with GC and Smith degradation. The structure characteristics were further discussed combined with infrared spectrophotometry. Dexamethasone-induced insulin resistance glucose/lipid metabolism diabetic mice model was established to evaluate the hypoglycemic effect of different concentration of HSY and different molecular weights polysaccharide HSY-I, HSY-II, and HSY-III. The results indicated that the HSY polysaccharide mixture, HSY-I and HSY-II had hypoglycemic effect. Three polysaccharides from Chinese yam tuber were isolated in this study. Their structures were characterized and hypoglycemic effects were evaluated. The result clearly identified the benefits of this plant as a healthy functional food. © 2017 Institute of Food Technologists®.

Fermentation optimization for the production of bioactive polysaccharides from Cordyceps sinensis fungus UM01.

PubMed

Wang, Lan-Ying; Cheong, Kit-Leong; Wu, Ding-Tao; Meng, Lan-Zhen; Zhao, Jing; Li, Shao-Ping

2015-08-01

The optimal fermentation conditions and medium for the production of bioactive polysaccharides from the mycelium of Cordyceps sinensis fungus UM01 were investigated by using orthogonal design and high performance size exclusion chromatography coupled with multi-angel laser light scattering and refractive index detector (HPSEC-MALLS-RID). Results showed that the optimal temperature, initial pH, rotation speed, medium capacity (ratio of medium volume to the volume of flask bottle) and inoculums volume for the mycelium growth were 15 °C, pH 6.0, 150 rpm, 2/5 (v/v), and 3% (v/v), respectively. Furthermore, bioactive polysaccharides from the mycelium of C. sinensis fungus UM01 were determined as polysaccharide fractions with the molecular weight above 10 kDa. The optimal fermentation medium was determined as a composition of glucose 30.0 g/L, sucrose 30.0 g/L, KH2PO4 1.0 g/L, CaCl2 0.5 g/L, yeast extract 3.0 g/L, and MgCl2 0.1g/L according to the maximum amount of the bioactive polysaccharides (486.16±19.60 mg/L) measured by HPSEC-MALLS/RID. Results are helpful to establish an efficient and controllable fermentation process for the industrial production of bioactive polysaccharides from C. sinensis UM01, and beneficial to develop a unique health and functional product in future. Copyright © 2015 Elsevier B.V. All rights reserved.

Protection by meningococcal outer membrane protein PorA-specific antibodies and a serogroup B capsular polysaccharide-specific antibody in complement-sufficient and C6-deficient infant rats.

PubMed

Toropainen, Maija; Saarinen, Leena; Vidarsson, Gestur; Käyhty, Helena

2006-05-01

The relative contributions of antibody-induced complement-mediated bacterial lysis and antibody/complement-mediated phagocytosis to host immunity against meningococcal infections are currently unclear. Further, the in vivo effector functions of antibodies may vary depending on their specificity and Fc heavy-chain isotype. In this study, a mouse immunoglobulin G2a (mIgG2a) monoclonal antibody (MN12H2) to meningococcal outer membrane protein PorA (P1.16), its human IgG subclass derivatives (hIgG1 to hIgG4), and an mIgG2a monoclonal antibody (Nmb735) to serogroup B capsular polysaccharide (B-PS) were evaluated for passive protection against meningococcal serogroup B strain 44/76-SL (B:15:P1.7,16) in an infant rat infection model. Complement component C6-deficient (PVG/c-) rats were used to assess the importance of complement-mediated bacterial lysis for protection. The PorA-specific parental mIgG2a and the hIgG1 to hIgG3 derivatives all induced efficient bactericidal activity in vitro in the presence of human or infant rat complement and augmented bacterial clearance in complement-sufficient HsdBrlHan:WIST rats, while the hIgG4 was unable to do so. In C6-deficient PVG/c- rats, lacking complement-mediated bacterial lysis, the augmentation of bacterial clearance by PorA-specific mIgG2a and hIgG1 antibodies was impaired compared to that in the syngeneic complement-sufficient PVG/c+ rat strain. This was in contrast to the case for B-PS-specific mIgG2a, which conferred similar protective activity in both rat strains. These data suggest that while anti-B-PS antibody can provide protection in the infant rats without membrane attack complex formation, the protection afforded by anti-PorA antibody is more dependent on the activation of the whole complement pathway and subsequent bacterial lysis.

[Separation, purification and primary reverse cholesterol transport study of Cordyceps militaris polysaccharide].

PubMed

Guo, Shou-Dong; Cui, Ying-Jie; Wang, Ren-Zhong; Wang, Ren-Yuan; Wu, Wen-Xue; Ma, Teng

2014-09-01

The authors designed to separate, purify and determine the monosaccharide composition of the polysaccharide from Cordyceps militaris, and study its effect on reverse cholesterol transport in vivo by isotope tracing assay. Polysaccharides were separate and purify by ion exchange column Q-sepharose Fast Flow and size exclusion column Sephacryl S200HR; the molecular weight and monosaccharide composition of the polysaccharides were determined by high performance gel permeation chromatography and high performance liquid chromatography coming with pre-column derivation, respectively. Finally, three purified polysaccharides CMBW1, CMBW2 and CMYW1 were obtained, their total carbohydrate contents were 87%, 89%, 95%, respectively; their protein contents were 6.5%, 1.3%, 2.8%, respectively; their molecular weights were 772.1, 20.9, 13.2 kDa, respectively; CMBW1 was composed of mannose, glucosamine, rhamnose, glucuronic acid, glucose, galactose and arabinose with a molar ratio of 7.25: 0.17: 1.29: 0.23: 6.30: 11.08: 0.79; CMBW2 was composed of mannose, glucosamine, galactose and arabinose with a molar ratio of 2.40: 0.16: 2.92: 0.24; CMYW1 was composed of mannose, glucosamine, glucuronic acid and glucose with a molar ratio of 0.59: 0.57: 0.45: 25.61. Polysaccharide at 50 mg x kg(-1) could significantly improve the transport of 3H- cholesterol to blood and excretion from feces. All of the three purified polysaccharides CMBW1, CMBW2 and CMYW1 were heteropolysaccharide; and they could improve reverse cholesterol transport in vivo, the underlying mechanisms are being studied.

Improved antimelanogenesis and antioxidant effects of polysaccharide from Cuscuta chinensis Lam seeds after enzymatic hydrolysis.

PubMed

Liu, Zi-Jun; Wang, Ya-Lan; Li, Qi-Ling; Yang, Liu

2018-01-01

Cuscuta chinensis polysaccharide (CPS) was extracted using hot water and enzymatically hydrolyzed C. chinensis polysaccharide (ECPS) was produced by the mannase enzymatic hydrolysis process. The purpose of this research was to investigate the antimelanogenic activity of ECPS and CPS in B16F10 melanoma cells. The in vitro antioxidant activity was assessed by their ferric iron reducing power and DPPH free radical scavenging activities. The molecular mass distribution of polysaccharides was determined using SEC-MALLS-RI. CPS was successfully enzymatically degraded using mannase and the weighted average molecular weights of CPS and ECPS were 434.6 kDa and 211.7 kDa. The results of biological activity assays suggested that the enzymatically hydrolyzed polysaccharide had superior antimelanogenic activity and antioxidant effect than the original polysaccharide. ECPS exhibited antimelanogenic activity by down-regulating the expression of tyrosinase, MITF, and TRP-1 without cytotoxic effects in B16F10 melanoma cells. In conclusion, ECPS have the potential to become a skin whitening product.

Characterization and immunomodulatory activity of polysaccharides derived from Dendrobium tosaense.

PubMed

Yang, Li-Chan; Lu, Ting-Jang; Hsieh, Chang-Chi; Lin, Wen-Chuan

2014-10-13

Dendrobium tosaense is a medicinal Dendrobium species widely used in traditional medicine. This study demonstrated some structural characterizations and immunomodulatory activity of the water-soluble polysaccharides derived from the stem of D. tosaense (DTP). DTP was fractioned using DEAE-650 M anion-exchange gel filtration chromatography, producing one neutral polysaccharide fraction (DTP-N), which was investigated for its structural characteristics, using HPAEC-PAD, HP-SEC, GC-MS, and NMR spectroscopy. DTP and DTP-N consisted of galactose, glucose, and mannose in ratios of 1:9.1:150.7 and 1:12.2:262.5, respectively. DTP-N comprised (1 → 4)Man as its main backbone, and its average molecular weight was 220 kDa. We also investigated the immunomodulatory effects of DTP administered orally to BALB/c mice for 3 weeks. DTP substantially boosted the population of splenic natural killer (NK) cells, NK cytotoxicity, macrophage phagocytosis, and cytokine induction in splenocytes. This is the first study to demonstrate the structural characteristics of an active polysaccharide derived from D. tosaense and its immunopharmacological effects in vivo. Copyright © 2014 Elsevier Ltd. All rights reserved.

Polysaccharides from Smilax glabra inhibit the pro-inflammatory mediators via ERK1/2 and JNK pathways in LPS-induced RAW264.7 cells.

PubMed

Lu, Chuan-li; Wei, Zhu; Min, Wang; Hu, Meng-mei; Chen, Wen-long; Xu, Xiao-jie; Lu, Chuan-jian

2015-05-20

The rhizomes of Smilax glabra have been used as both food and folk medicine in many countries for a long time. However, little research has been reported on polysaccharides of S. glabra. In the present study, two polysaccharide fractions, SGP-1 and SGP-2, were isolated from the rhizomes of S. glabra with the number average molecular weights of 1.72 × 10(2)kDa and 1.31 × 10(2)kDa, and the weight average molecular weights of 1.31 × 10(5)kDa and 1.18 × 10(5)kDa, respectively, and their mainly monosaccharide compositions were both galactose and rhamnose (2.5:1). Both SGP-1 and SGP-2 significantly suppressed the release of nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) from LPS-induced RAW 264.7 cells, as well as the mRNA expression of inducible nitric oxide synthase (iNOS), TNF-α and IL-6. Additionally, SGP-1 and SGP-2 repressed the extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK). These findings strongly suggested polysaccharides were also the anti-inflammatory active ingredient for S. glabra, and the potential of SGP-1 and SGP-2 as the anti-inflammatory agents. Copyright © 2015. Published by Elsevier Ltd.

Characterization of polysaccharides with marked inhibitory effect on lipid accumulation in Pleurotus eryngii.

PubMed

Chen, Jingjing; Yong, Yangyang; Xing, Meichun; Gu, Yifan; Zhang, Zhao; Zhang, Shizhu; Lu, Ling

2013-09-12

Mushrooms have a great potential for the production of useful bioactive metabolites. To explore the bioactive compounds from edible mushrooms for interfering with the development of macrophage-derived foam cells, which is recognized as the hallmark of early atherosclerosis, eight types of mushrooms polysaccharides had been selected to be tested. Consequently, different mushrooms polysaccharides displayed diverse component profiles. Of polysaccharides that we tested, the Pleurotus eryngii polysaccharide had the strongest inhibitory effect on lipid accumulation. Furthermore, through fractionation of DEAE-52 and Sephadex G-100, the polysaccharide from P. eryngii had been successfully purified and identified. By the analysis of IR, GC, and HPLC, the purified polysaccharide was estimated to be 30-38 kDa for the average molecular weight with the monosaccharide composition mainly composed of D-types of mannose, glucose and galactose. Findings presented in this report firstly provide direct evidence, which links the purified polysaccharide moiety with the biological function in foam-cell model. Copyright © 2013 Elsevier Ltd. All rights reserved.

Physicochemical properties, immunomodulation and antitumor activities of polysaccharide from Pavlova viridis.

PubMed

Sun, Liqin; Chu, Jinling; Sun, Zhongliang; Chen, Lihong

2016-01-01

Polysaccharides synthesized by microalgae can be used as the functional ingredients of food or drugs. Here, we investigated the physicochemical properties and bioactivities of the polysaccharide from microalgae Pavlova viridis, and indicated the structure-activity relationship. The polysaccharides (PPS0) were degraded with H2O2-vitamin C assisted by ultrasonic waves. The functional group content, monosaccharide composition, and average molecular weight (avg-MW) were detected by chemical or chromatographic method. The immunomodulatory activities were evaluated in vitro by detecting nitric oxide (NO) emission, neutral red uptake and macrophage proliferation. Antitumor activities of degraded fragments were detected using S180-tumor-bearing mouse model by intragastric administration. Degraded polysaccharides PPS1 and PPS2 were obtained at avg-MW of 386.96 and 54.99 kDa. The sulfate group content of polysaccharide was 16%, and the uronic acid content was 5.88 and 8.48%. PPS mainly consisted of fructose, glucose and mannose. All the degraded PPSs could increase phagocytosis and proliferation of macrophages, and stimulated NO emission in a dose-dependently way. PPS2 in Low-MW fragments had the strongest immunoenhancing activities. Different doses of PPS all could inhibit the growth of implanted S180 tumor. At dose of 200 mg/kg/day, the tumor inhibition rate of PPS2 was 57.06%, about 23.6% less than that of CTX-treated group. Different-MW PPS significantly increased lymphocyte proliferation. At 200 mg/L, the proliferation index of PPS2 was 1.37, 2.03 times higher than that of CTX-treated group. The polysaccharides of Pavlova viridis had potential antitumor activities by improving immune response. Moreover, the bioactivities depend on their molecular weight. Copyright © 2015 Elsevier Inc. All rights reserved.

Does the Hip Capsule Remain Closed After Hip Arthroscopy With Routine Capsular Closure for Femoroacetabular Impingement? A Magnetic Resonance Imaging Analysis in Symptomatic Postoperative Patients.

PubMed

Weber, Alexander E; Kuhns, Benjamin D; Cvetanovich, Gregory L; Lewis, Paul B; Mather, Richard C; Salata, Michael J; Nho, Shane J

2017-01-01

The purpose of this study was to examine the hip capsule in a subset of symptomatic patients who underwent capsular closure during hip arthroscopy. All patients undergoing primary hip arthroscopy for femoroacetabular impingement (FAI) with routine capsular closure between January 1, 2012, and December 31, 2015, were eligible. Only patients with unilateral surgery and a postoperative magnetic resonance imaging (MRI; ordered for persistent symptoms) were included. Four independent reviewers evaluated each hip capsule for thickness and the absence or presence of defects. During the study, 1,463 patients had hip arthroscopy for FAI with routine capsular closure, and 53 (3.6%) underwent a postoperative MRI. Fourteen of the 53 were excluded owing to revision status or additional procedures. The final study population included 39 patients (23 female patients and 16 male patients), with an average patient age of 31.7 ± 11.4 years and an average body mass index of 23.3 ± 2.9. There were 3 (7.5%) capsular defects, and the intraclass correlation coefficient (ICC) was 0.82. The operative hip capsule was significantly thicker in the zone of capsulotomy, and subsequent repair as compared with the unaffected, contralateral hip capsule (5.0 ± 1.2 mm vs 4.6 ± 1.4 mm; P = .02), ICC 0.83. Additionally, males had thicker hip capsules as compared with their female counterparts, on the operative side (5.4 ± 1.1 mm vs 4.5 ± 1.2 mm; P = .02) and the nonoperative side (4.8 ± 1.6 mm vs 4.1 ± 0.9 mm; P = .08). In a subset of symptomatic patients after hip arthroscopy for FAI, the majority (92.5%) of the repaired hip capsules remained closed at greater than 1 year of follow-up. The hip capsule adjacent to the capsulotomy and subsequent repair is thickened compared with the same location on the contralateral, nonoperative hip. Aside from gender, patient-related and FAI-related factors do not correlate with capsular thickness nor do they seem to correlate with the propensity

Hypolipidemic effects of crude green tea polysaccharide on rats, and structural features of tea polysaccharides isolated from the crude polysaccharide.

PubMed

Nakamura, Michiko; Miura, Sayaka; Takagaki, Akiko; Nanjo, Fumio

2017-05-01

Crude tea polysaccharide (crude TPS) was prepared from instant green tea by ethanol precipitation followed by ultrafiltration membrane treatment and its effects on blood lipid, liver lipid, and fecal lipid levels were examined with Sprague-Dawley rats fed a high-fat diet. Although crude TPS showed no effects on the serum lipid levels, it suppressed the liver lipid accumulation and increased the fecal excretion of dietary fat. Then, the structural features of crude TPS were investigated. After separation of crude TPS by DEAE-cellulose and gel-filtration column chromatography, two kinds of neutral tea polysaccharides (NTPS-LP and NTPS-HH) and an acidic polysaccharide (ATPS-MH) were obtained. According to monosaccharide composition, methylation, and NMR analyses, NTPS-LP, NPTS-HH, and ATPS-MH were presumed to be starch, arabinogalactan with β-1,3-linked galactosyl backbone blanched at position 6 and with 1,5-linked arabinofuranosyl residues, and α-1,4-linked galacturonic acid backbone with arabinogalactan region, respectively.

Distribution of capsular types and antimicrobial susceptibility of invasive isolates of Streptococcus pneumoniae in Colombian children. Pneumococcal Study Group in Colombia.

PubMed

Castañeda, E; Leal, A L; Castillo, O; De La Hoz, F; Vela, M C; Arango, M; Trujillo, H; Levy, A; Gama, M E; Calle, M; Valencia, M L; Parra, W; Agudelo, N; Mejía, G I; Jaramillo, S; Montoya, F; Porras, H; Sánchez, A; Saa, D; Di Fabio, J L; Homma, A

1997-01-01

Streptococcus pneumoniae is the leading bacterial cause of childhood pneumonia in the developing world. This study describes the type distribution and antimicrobial susceptibility of invasive pneumococcal isolates from Colombian children and is part of the Sistema Regional de Vacunas (SIREVA), a PAHO regional initiative designed to determine the ideal serotype composition of a protein polysaccharide pneumococcal conjugate vaccine for use in children less than 5 years old in Latin America. In Colombia, during the study period, centres in Bogota, Medellin, and Cali collected 324 S. pneumoniae isolates from invasive diseases, 238 (73.5%) from children under the age of 2. Pneumonia was the clinical diagnosis in 41.3% cases, meningitis in 41%, and sepsis in 11.2%. The seven most frequent types included 14(21.9%), 5(10.5%), 23F(9.6%), 1(9%), 6B(9%), 19F(7.1%), and 6A(6.2%). The frequency of diminished susceptibility to penicillin (DSP) was 12%, with 8.9% of isolates showing intermediate level resistance and 3.1% showing high level resistance. Among DSP isolates, 23% were also resistant to cefotaxime, 33.3% to erythromycin, 48.7% to chloramphenicol, and 74.3% to trimethoprim/sulfamethoxazole. Multiple resistance was detected in 59% of the isolates that have DSP. Penicillin resistance was associated with types 23F (53.8%) and 14 (25.6%). These data provides information on capsular types prevalent in Colombia that will not only allow the formulation of an ideal vaccine for the region but also reinforce the need for ongoing regional surveillance.

Chemical characteristics and anti-proliferation activities of Ganoderma tsugae polysaccharides.

PubMed

Chien, Rao-Chi; Yen, Ming-Tsung; Tseng, Yu-Hsiu; Mau, Jeng-Leun

2015-09-05

Polysaccharides were extracted by hot-water and hot-alkali from four forms of Ganoderma tsugae including mature and baby Ling chih, mycelium and filtrate. Different profiles of proximate composition and monosaccharide constituents, and element contents were found in the extracted polysaccharides from different extractions and different forms. The molecular weight distributions of polysaccharides were 2.8×10(4)-6.5×10(5)Da and their infrared spectra were comparable. The hot-alkali extracted polysaccharides exhibited better anti-proliferation on IMR32 cells than the hot-water extracted polysaccharides, which were in turn more effective than the hot-water extracts. Besides, most hot-water extracts and both extracted polysaccharides exhibited an anti-proliferation effect on Hep G2 cells. However, the hot-water extracts showed less effective in anti-proliferation of IMR32 and Hep G2 cells. Based on the anti-tumor effects, both polysaccharides could be prepared for use in the formulation of nutraceuticals and functional foods. Copyright © 2015 Elsevier Ltd. All rights reserved.

A novel enzyme-linked immuno-sorbent assay (ELISA) for the quantification of total and free polysaccharide in Haemophilus influenzae b-Tetanus toxoid conjugate vaccines in monovalent and combined vaccine formulations.

PubMed

Saydam, Manolya; Rigsby, Peter; Mawas, Fatme

2014-01-01

Current Haemophilus influenzae b conjugate vaccines (Hib), which are made of purified capsular polysaccharide (poly-ribosyl-ribitol-phosphate; PRP) conjugated to a carrier protein, are almost completely evaluated by physico-chemical methods to ensure the integrity and stability of the vaccine and consistency of manufacture of batches. The absence of a potency assay makes the quantification of total PRP content (in SI units) and of % free polysaccharide in final fills or bulk components of Hib vaccines critical release tests for both manufacturers and national control authorities. Here we describe a simple and sensitive Enzyme-Linked Immuno-sorbent Assay (ELISA) which has been developed to quantify total and free PRP content in Hib-TT vaccine alone or when in combination with other vaccines. The assay is robust, specific and highly sensitive. Copyright © 2013 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

Anterior capsular rupture following blunt ocular injury

PubMed Central

Gremida, Anas; Kassem, Iris; Traish, Aisha

2011-01-01

Summary A 10-year-old boy suffered a large, oblique anterior capsular tear following blunt injury to his right eye. The boy was followed daily for hyphema resolution and progressive traumatic cataract formation. After the hyphema had resolved, the lens was removed using an anterior approach and an intraocular lens was placed with excellent visual outcome. PMID:23362402

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

Polysaccharide K and Coriolus versicolor extracts for lung cancer: a systematic review.

PubMed

Fritz, Heidi; Kennedy, Deborah A; Ishii, Mami; Fergusson, Dean; Fernandes, Rochelle; Cooley, Kieran; Seely, Dugald

2015-05-01

Polysaccharide K, also known as PSK or Krestin, is derived from the Coriolus versicolor mushroom and is widely used in Japan as an adjuvant immunotherapy for a variety of cancer including lung cancer. Despite reported benefits, there has been no English language synthesis of PSK for lung cancer. To address this knowledge gap, we conducted a systematic review of PSK for the treatment of lung cancer. We searched PubMed, EMBASE, CINAHL, the Cochrane Library, AltHealth Watch, and the Library of Science and Technology from inception to August 2014 for clinical and preclinical evidence pertaining to the safety and efficacy of PSK or other Coriolus versicolor extracts for lung cancer. Thirty-one reports of 28 studies were included for full review and analysis. Six studies were randomized controlled trials, 5 were nonrandomized controlled trials, and 17 were preclinical studies. Nine of the reports were Japanese language publications. Fifteen of 17 preclinical studies supported anticancer effects for PSK through immunomodulation and potentiation of immune surveillance, as well as through direct tumor inhibiting actions in vivo that resulted in reduced tumor growth and antimetastatic effects. Nonrandomized controlled trials showed improvement of various survival measures including median survival and 1-, 2-, and 5-year survival. Randomized controlled trials showed benefits on a range of endpoints, including immune parameters and hematological function, performance status and body weight, tumor-related symptoms such as fatigue and anorexia, as well as survival. Although there were conflicting results for impact on some of the tumor-related symptoms and median survival, overall most randomized controlled trials supported a positive impact for PSK on these endpoints. PSK was safely administered following and in conjunction with standard radiation and chemotherapy. PSK may improve immune function, reduce tumor-associated symptoms, and extend survival in lung cancer patients

Studies on water soluble polysaccharides from Pithecellobium dulce (Roxb.) Benth. seeds.

PubMed

Bagchi, S; Kumar, K Jayaram

2016-03-15

In this existing experimental work, water soluble PDP polysaccharides were secluded from Pithecellobium dulce (Roxb.) Benth. seeds. The physicochemical properties were analyzed in terms of swelling power, solubility, pH and water holding capacity. Micromeretic studies proved the polysaccharide may be used a potential pharmaceutical adjuvant. The polysaccharide was characterized by FT-IR, SEM, TGA and NMR techniques. Methylation analysis confirmed that the polysaccharide is composed of Arabinose (Araf) units. The chemical shifts of anomeric proton region were found in the region of 4.4-5.5ppm. Thermogravimetric analysis showed that PDP polysaccharide was thermally stable. The in vitro antioxidant capacities of the polysaccharide were investigated in terms of scavenging of hydroxyl radicals, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radicals, hydrogen peroxide (H2O2) and reducing power assay. The polysaccharide fractions showed activity in a concentration dependent manner which was comparable to the standard, ascorbic acid. Copyright © 2015 Elsevier Ltd. All rights reserved.

Fermentation of polysaccharides by Klebsiella and other facultative bacilli

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ochuba, G.U.; Von Riesen, V.L.

1980-05-01

Fermentations of 10 polysaccharides by species of the family Enterobacteriaceae were examined. Algin, guar, karaya, xanthan, and xylan were not fermented by any of the strains tested. Most of the activity was found in the tribe Klebsielleae. Klebseilla oxytoca fermented amylopectin (97% of the strains studied), carrageenan (100%), inulin (68%), polypectate (100%), and tragacanth (100%). Klebsiella pneumoniae fermented amylopectin (91%), carrageenan (100%), and tragacanth (86%). Carraggeenan was also fermented by Enterobacter aerogenes (100%), Enterobacter agglomerans (63%), Enterobacter cloacae (95%), and pectobacterium (38%). pectobacterium shared polypectate fermentation (100%) with K. oxytoca. With one exception, Serratia strains were negative on all polysaccharides.more » These results, along with other evidence, indicate that (i) the genus Klebsiella is biochemically the most versatile genus of the tribe, (ii) because of its distinct characteristics, K. oxytoca warrants species designation separate from K. pneumoniae, and (iii) some food additives generally considered indigestible can be metabolized by a few species of facultative bacilli, whereas others appear to be resistant.« less

Short-term evaluation of arthroscopic management of tennis elbow; including resection of radio-capitellar capsular complex.

PubMed

Babaqi, AbdulRahman A; Kotb, Mohammed M; Said, Hatem G; AbdelHamid, Mohamed M; ElKady, Hesham A; ElAssal, Maher A

2014-06-01

There has been controversy regarding the pathogenesis and treatment of lateral epicondylitis. Different surgical techniques for the treatment of lateral epicondylitis prescribed. The purpose of this study was to evaluate the short-term outcomes of arthroscopic management including resection of the radio-capitellar capsular complex, using different validated scores. In this study, arthroscopic resection of a capsular fringe complex was done beside debridement of the undersurface of Extensor Carpi Radialis Brevis (ECRB). Thirty-one patients with recalcitrant lateral epicondylitis for a minimum of 6 months had surgery. In all patients, a collar-like band of radio-capitellar capsular complex was found to impinge on the radial head and subluxate into the radio-capitellar joint with manipulation under direct vision. Outcomes were assessed using Mayo Elbow Performance Index (MEPI), the Patient-Rated Tennis Elbow Evaluation (PRTEE), and the Disability of the Arm, Shoulder, and Hand (DASH), beside visual analog scale (VAS) for pain and satisfaction criteria. After arthroscopic surgery, overall satisfaction was extremely positive, over the 31 patients, 93.5% of the patients are satisfied. The mean score for pain improved from 8.64 to 1.48 points. The total PRTEE improved from 55.53 to 10.39 points. The mean MEPI score was improved from 61.82 to 94.10 points. DASH score also improved from 24.46 to 4.81 points. All improvements are statistically significant (P < 0.05). Arthroscopic release of ECRB in patients with chronic lateral epicondylitis is a reproducible method with a marked improvement in function within a short period, with special consideration for resection of radio-capitellar capsular complex.

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. Copyright © 2014 Elsevier B.V. All rights reserved.

STUDIES ON NON-HEMOLYTIC STREPTOCOCCI ISOLATED FROM THE RESPIRATORY TRACT OF MAN

PubMed Central

Horsfall, Frank L.

1951-01-01

The type specific immunological properties of certain non-hemolytic streptococci, including Str. salivarius type I and type II, present in the respiratory tract of human beings appear to be dependent upon the presence of capsular polysaccharides. The levans formed from sucrose by Str. salivarius (encapsulated S cells or non-encapsulated R variants), or by cell-free enzymes derived from these microorganisms, are indistinguishable immunologically and show no evidence of type specificity. Such levans appear to be immunologically distinct from and unrelated to the capsular polysaccharides of the microorganisms which produce them. PMID:14824398

In vitro prebiotic effects of seaweed polysaccharides

NASA Astrophysics Data System (ADS)

Chen, Xiaolin; Sun, Yuhao; Hu, Linfeng; Liu, Song; Yu, Huahua; Xing, Rong'e.; Li, Rongfeng; Wang, Xueqin; Li, Pengcheng

2017-09-01

Although prebiotic activities of alginate and agar oligosaccharides isolated from seaweeds have been reported, it remains unknown whether seaweed polysaccharides have prebiotic activity. In this study, we isolated polysaccharides from four species of seaweeds, such as Grateloupia filicina (GFP), Eucheuma spinosum (ESP), Ulva pertusa (UPP), and Ascophyllum nodosum (ANP), and characterized their structures and prebiotic effects in vitro. The results showed that these polysaccharides were different in total sugar and sulfate contents as well as monosaccharide composition. GFP and ESP significantly promoted bifidobacterium proliferation and 0.1% ESP and 0.4% GFP resulted in the highest proliferation rates of beneficial bacteria, whereas UPP and ANP inhibited the growth of beneficial bacteria at all tested concentrations (0.1%-0.5%). The different behaviors of the four seaweed-originated polysaccharides might be reflected by differences in monosaccharide composition and structure. Therefore, polysaccharides isolated from GFP and ESP could be utilized as prebiotics. However, more studies must be carried out in vivo.

Genomic Investigation Reveals Highly Conserved, Mosaic, Recombination Events Associated with Capsular Switching among Invasive Neisseria meningitidis Serogroup W Sequence Type (ST)-11 Strains.

PubMed

Mustapha, Mustapha M; Marsh, Jane W; Krauland, Mary G; Fernandez, Jorge O; de Lemos, Ana Paula S; Dunning Hotopp, Julie C; Wang, Xin; Mayer, Leonard W; Lawrence, Jeffrey G; Hiller, N Luisa; Harrison, Lee H

2016-07-03

Neisseria meningitidis is an important cause of meningococcal disease globally. Sequence type (ST)-11 clonal complex (cc11) is a hypervirulent meningococcal lineage historically associated with serogroup C capsule and is believed to have acquired the W capsule through a C to W capsular switching event. We studied the sequence of capsule gene cluster (cps) and adjoining genomic regions of 524 invasive W cc11 strains isolated globally. We identified recombination breakpoints corresponding to two distinct recombination events within W cc11: A 8.4-kb recombinant region likely acquired from W cc22 including the sialic acid/glycosyl-transferase gene, csw resulted in a C→W change in capsular phenotype and a 13.7-kb recombinant segment likely acquired from Y cc23 lineage includes 4.5 kb of cps genes and 8.2 kb downstream of the cps cluster resulting in allelic changes in capsule translocation genes. A vast majority of W cc11 strains (497/524, 94.8%) retain both recombination events as evidenced by sharing identical or very closely related capsular allelic profiles. These data suggest that the W cc11 capsular switch involved two separate recombination events and that current global W cc11 meningococcal disease is caused by strains bearing this mosaic capsular switch. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

The Effect of Capsulotomy and Capsular Repair on Hip Distraction: A Cadaveric Investigation.

PubMed

Khair, M Michael; Grzybowski, Jeffrey S; Kuhns, Benjamin D; Wuerz, Thomas H; Shewman, Elizabeth; Nho, Shane J

2017-03-01

To quantify how increasing interportal capsulotomy size affects the force required to distract the hip and to biomechanically compare simple side-to-side suture repair to acetabular-based suture anchors as capsular repair techniques. Twelve fresh-frozen cadaveric hip specimens were dissected to the capsuloligamentous complex of the hip joint and fixed in a material testing system, such that a pure axial distraction of the iliofemoral ligament could be achieved. After each hip in was tested an intact state, sequential distraction was tested with 2, 4, 6, and 8 cm capsulotomies. Specimens were assigned randomly to be repaired with either 4 side-to-side suture repair (n = 6) or 2 double-loaded all-suture anchors (n = 6). The distraction force as well as the relative distraction force percentage normalized to the intact capsule were compared between suture repair and suture anchor repair groups. Increasing the size of the capsulotomy resulted in less force required to distract the hip to 6 mm. The force decreased as the capsulotomy was extended with statistical significance in distraction force seen between the intact state and the 4 cm (P = .003), 6 cm (P < .001), and 8 cm (P ≤ .001) capsulotomy but not for the intact state compared to the 2 cm capsulotomy (P = .28). Statistical significance in relative distraction force was seen for each of the capsulotomy conditions (P < .001 for all conditions compared with the intact state). The side-to-side suture repair construct (104.3% of intact force) required greater force to distraction to 6 mm compared with the suture anchor repair (87.1% of intact force) (P = .008). An interportal capsulotomy significantly affected the force required to distract the hip in a cadaveric model, with the larger the size of capsulotomy resulting in less force required to distract the hip. When we performed an interportal capsulotomy, the iliofemoral ligament strength was altered significantly but capsular repair with either

Simultaneous analysis of 18 mineral elements in Cyclocarya paliurus polysaccharide by ICP-AES.

PubMed

Xie, Jian-Hua; Shen, Ming-Yue; Nie, Shao-Ping; Liu, Xin; Yin, Jun-Yi; Huang, Dan-Fei; Zhang, Hui; Xie, Ming-Yong

2013-04-15

The contents of 18 kinds of mineral elements in Cyclocarya paliurus polysaccharide samples were determined by ICP-AES. The limits of detection (LOD) of the method for 18 elements were in the range of 0.01-3.80 mg/kg. The average recoveries obtained by the standard addition method were found between 94.34% and 105.69% (RSD, 1.01-4.23%). The results showed that C. paliurus polysaccharides were abundant in major and trace elements which are healthy for human body. The contents of Ca, Al, Mg, K, Fe, Mn and P were very high, ranging from 274.5±10.3 to 5980.0±102.7 mg/kg, while the contents of Zn, Na, Se, Cr, Pb, Cu and As ranged from 0.9±0.1 to 37.1±4.2 mg/kg. Finally, the levels of Ni, Cd, V and Co were not detected in the samples. ICP-AES is a simple, precise and efficient method for the determination of many mineral elements in polysaccharide samples simultaneously. Copyright © 2013 Elsevier Ltd. All rights reserved.

Improved Extraction and Quality Characterization of Water-Soluble Polysaccharide from Gamma-Irradiated Lentinus edodes.

PubMed

Akram, Kashif; Shahbaz, Hafiz Muhammad; Kim, Gui-Ran; Farooq, Umar; Kwon, Joong-Ho

2017-02-01

Gamma irradiation was applied to the improved extraction of water-soluble polysaccharides (WSPs) from dried Lentinus edodes. Irradiation provided a dose-dependent increase in extraction yield (0 kGy, 2.01%; 7.5 kGy, 4.03%; 15 kGy, 7.17%) and purity (0 kGy, 78.8%; 7.5 kGy, 83.1%; 15 kGy, 85.6%) of the WSPs from hot-water extraction. The effect of irradiation was evident in the degraded microstructures and reduced molecular weights of the WSPs. However, nuclear magnetic resonance, Fourier-transform infrared, and X-ray diffraction spectroscopic analyses provided comparable structures of WSPs from nonirradiated and irradiated samples. UV-visible spectra showed a dose-dependent decline in intensity, but an improvement in thermal properties of the WSPs from the irradiated mushroom samples was observed. © 2017 Institute of Food Technologists®.

Influence of surface polysaccharides of Escherichia coli O157:H7 on plant defense response and survival of the human enteric pathogen on Arabidopsis thaliana and lettuce (Lactuca sativa).

PubMed

Jang, Hyein; Matthews, Karl R

2018-04-01

This study aimed to determine the influence of bacterial surface polysaccharides (cellulose, colanic acid, and lipopolysaccharide; LPS) on the colonization or survival of Escherichia coli O157:H7 on plants and the plant defense response. Survival of E. coli O157:H7 were evaluated on Arabidopsis thaliana and romaine lettuce as a model plant and an edible crop (leafy vegetable), respectively. The population of the wild-type strain of E. coli O157:H7 on Arabidopsis plants and lettuce was significantly (P < 0.05) greater compared with the colanic acid-deficient and LPS-truncated mutants on day 1 and day 5 post-inoculation. This result indicates that colanic acid and LPS structures may contribute to the ability of bacterial survival or persistence on plants. The wild-type strain of E. coli O157:H7 produced approximately twice the amount (P < 0.05) of capsular polysaccharide (CPS) than the colanic acid and LPS-truncated mutants. The significantly lower production of CPS was associated with significantly greater (2-fold) expression of pathogenesis-related gene (PR1) compared with the wild-type and cellulose-deficient mutant (P < 0.05). Collectively, the results of this study may suggest that specific surface polysaccharides of E. coli O157:H7 differentially induce the plant defense response, consequently affecting the survival of the human pathogen on plants. The survival and persistence of E. coli O157:H7 was similar on Arabidopsis and lettuce regardless of day post-inoculation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Capsulorhexis ovaling and capsular bag stretch after rigid and foldable intraocular lens implantation: experimental study in pediatric human eyes.

PubMed

Pandey, Suresh K; Werner, Liliana; Wilson, M Edward; Izak, Andrea M; Apple, David J

2004-10-01

To compare the amount of capsulorhexis ovaling and capsular bag stretch produced by various intraocular lenses (IOLs) implanted in pediatric human eyes obtained post-mortem. David J. Apple, MD Laboratories for Ophthalmic Devices Research, John A. Moran Eye Center, Salt Lake City, Utah, USA. In this nonrandomized comparative study, 16 pediatric human eyes obtained postmortem were divided into 2 groups: Eight eyes were obtained from children younger than 2 years (Group A), and 8 eyes were obtained from children older than 2 years (Group B). All eyes were prepared according to the Miyake-Apple posterior video technique. Six types of rigid and foldable posterior chamber IOLs manufactured from poly(methyl methacrylate) (single-piece), silicone (plate and loop haptics), and hydrophobic acrylic (single-piece and 3-piece AcrySof, Alcon Laboratories) biomaterials were implanted. The capsulorhexis opening and capsular bag diameters were measured before IOL implantation and after in-the-bag IOL fixation with the haptics (or the main axis) at the 3 to 9 o'clock meridian. The percentage of ovaling of the capsulorhexis opening was calculated by noting the difference in the opening's horizontal diameter before and after IOL implantation. The percentage of capsular bag stretch was also calculated by noting the difference in the horizontal capsular bag diameter before and after IOL implantation. All IOLs produced ovaling of the capsulorhexis opening and stretching of the capsular bag parallel to the IOL haptics. There were significant differences in capsulorhexis ovaling and capsular bag stretch (P<.001, analysis of variance) between the 6 IOL types in each group of eyes. The postimplantation difference was significant only between the single-piece hydrophobic acrylic IOL (AcrySof) and the other IOLs. The single-piece hydrophobic acrylic IOL was associated with significantly less capsulorhexis ovaling and capsular bag stretch in both groups (mean 12.06% +/- 0.59% [SD] and 7

Fishtail on a line technique for capsular tension ring insertion.

PubMed

Rixen, Jordan J; Oetting, Thomas A

2014-07-01

We describe a capsular tension ring (CTR) insertion technique that is a modification of the previously described fishtail technique. A suture line is used to pull the leading eyelet out through the main incision to form the fish configuration. Similar to the fishtail technique, this insertion technique minimizes the risk for zonular damage or a capsule tear because the CTR is not dialed into the capsular bag. The advantage of the suture line is that it prevents over bending of the CTR during insertion through the main incision, which can occur using the traditional fishtail technique. Neither author has a financial or proprietary interest in any material or method mentioned. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Characteristics of fucose-containing polysaccharides from submerged fermentation of Agaricus blazei Murill.

PubMed

Wang, Hsueh-Ting; Yang, Li-Chan; Yu, Hui-Ching; Chen, Miaw-Ling; Wang, Huei-Ju; Lu, Ting-Jang

2018-04-01

Fucose is one of important residues of recognition pattern for many immune cells. In this study, we characterized bioactive fucose-containing acidic polysaccharides from submerged fermentation of Agaricus blazei Murill. We obtained the polysaccharides through a cell-based activity-guided strategy, and used carbohydrate recognition monoclonal antibodies based Enzyme-Linked Immuno Sorbent Assay (ELISA) along with methylation and NMR analyses to investigate the structural characteristics of the polysaccharides. The polysaccharides had Mw of 3.5 × 10 5  Da. The major sugars were l-fucose, l-arabinose, d-galactose, d-xylose, and d-galacturonic acid in the molar ratio of 6.4, 15.5, 28.5, 14.7, and 25.0% with a small amount of d-glucose, d-mannose, l-rhamnose, and d-glucuronic acid. Results indicated that the bioactive polysaccharides consisted of a (1,4)-Galp and (1,4)-GalAp back bone; (1,2)-Xyl and (1,2)-Rha might also comprise backbone or constitute side chain; linkage (1,5)-Ara and terminal fucosyl residues were also involved in the polysaccharides. Regarding bioactivity, removal of the terminal l-fucosyl residues reduced the TNF-α cytokine stimulating activity of the polysaccharides in a RAW 264.7 macrophage cell-line test, whereas NF-κB and TLR4 affected the polysaccharide-induced TNF-α production. Copyright © 2017. Published by Elsevier B.V.

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. Copyright © 2013 Elsevier B.V. All rights reserved.

Protective Immunity Against a Lethal Respiratory Yersinia pestis Challenge Induced by V Antigen or the F1 Capsular Antigen Incorporated into Adenovirus Capsid

PubMed Central

Boyer, Julie L.; Sofer-Podesta, Carolina; Ang, John; Hackett, Neil R.; Chiuchiolo, Maria J.; Senina, Svetlana; Perlin, David

2010-01-01

Abstract The aerosol form of the bacterium Yersinia pestis causes pneumonic plague, a rapidly fatal disease that is a biothreat if deliberately released. At present, no plague vaccines are available for use in the United States, but subunit vaccines based on the Y. pestis V antigen and F1 capsular protein show promise when administered with adjuvants. In the context that adenovirus (Ad) gene transfer vectors have a strong adjuvant potential related to the ability to directly infect dendritic cells, we hypothesized that modification of the Ad5 capsid to display either the Y. pestis V antigen or the F1 capsular antigen on the virion surface would elicit high V antigen- or F1-specific antibody titers, permit boosting with the same Ad serotype, and provide better protection against a lethal Y. pestis challenge than immunization with equivalent amounts of V or F1 recombinant protein plus conventional adjuvant. We constructed AdYFP-pIX/V and AdLacZ-pIX/F1, E1–, E3– serotype 5 Ad gene transfer vectors containing a fusion of the sequence for either the Y. pestis V antigen or the F1 capsular antigen to the carboxy-terminal sequence of pIX, a capsid protein that can accommodate the entire V antigen (37 kDa) or F1 protein (15 kDa) without disturbing Ad function. Immunization with AdYFP-pIX/V followed by a single repeat administration of the same vector at the same dose resulted in significantly better protection of immunized animals compared with immunization with a molar equivalent amount of purified recombinant V antigen plus Alhydrogel adjuvant. Similarly, immunization with AdLacZ-pIX/F1 in a prime–boost regimen resulted in significantly enhanced protection of immunized animals compared with immunization with a molar-equivalent amount of purified recombinant F1 protein plus adjuvant. These observations demonstrate that Ad vaccine vectors containing pathogen-specific antigens fused to the pIX capsid protein have strong adjuvant properties and stimulate more robust

Cryptococcus neoformans responds to mannitol by increasing capsule size in vitro and in vivo

PubMed Central

Guimarães, Allan Jefferson; Frases, Susana; Cordero, Radamés J. B.; Nimrichter, Leonardo; Casadevall, Arturo; Nosanchuk, Joshua D.

2010-01-01

The polysaccharide capsule of the fungus Cryptococcus neoformans is its main virulence factor. In this study, we determined the effects of mannitol and glucose on the capsule and exopolysaccharide production. Growth in mannitol significantly increased capsular volume compared to cultivation in glucose. However, cells grown in glucose concentrations higher than 62.5mM produced more exopolysaccharide than cells grown in mannitol. The fiber lengths and glycosyl composition of capsular polysaccharide from yeast grown in mannitol was structurally different from that of yeast grown in glucose. Furthermore, mannitol treatment of mice infected intratracheally with C. neoformans resulted in fungal cells with significantly larger capsules and the mice had reduced fungal dissemination to the brain. Our results demonstrate the capacity of carbohydrate source and concentration to modify the expression of a major virulence factor of C. neoformans. These findings may impact the clinical management of cryptococcosis. PMID:20070311

Anatomic and Histological Investigation of the Anterolateral Capsular Complex in the Fetal Knee.

PubMed

Sabzevari, Soheil; Rahnemai-Azar, Amir Ata; Albers, Marcio; Linde, Monica; Smolinski, Patrick; Fu, Freddie H

2017-05-01

There is currently disagreement with regard to the presence of a distinct ligament in the anterolateral capsular complex of the knee and its role in the pivot-shift mechanism and rotatory laxity of the knee. To investigate the anatomic and histological properties of the anterolateral capsular complex of the fetal knee to determine whether there exists a distinct ligamentous structure running from the lateral femoral epicondyle inserting into the anterolateral tibia. Descriptive laboratory study. Twenty-one unpaired, fresh fetal lower limbs, gestational age 18 to 22 weeks, were used for anatomic investigation. Two experienced orthopaedic surgeons performed the anatomic dissection using loupes (magnification ×3.5). Attention was focused on the anterolateral and lateral structures of the knee. After the skin and superficial fascia were removed, the iliotibial band was carefully separated from underlying structures. The anterolateral capsule was then examined under internal and external rotation and varus-valgus manual loading and at different knee flexion angles for the presence of any ligamentous structures. Eight additional unpaired, fetal lower limbs, gestational age 11 to 23 weeks, were used for histological analysis. This study was not able to prove the presence of a distinct capsular or extracapsular ligamentous structure in the anterolateral capsular complex area. The presence of the fibular collateral ligament, a distal attachment of the biceps femoris, the entire lateral capsule, the iliotibial band, and the popliteus tendon in the anterolateral and lateral area of the knee was confirmed in all the samples. Histological analysis of the anterolateral capsule revealed a loose, hypocellular connective tissue with less organized collagen fibers compared with ligament and tendinous structures. The main finding of this study was that the presence of a distinct ligamentous structure in the anterolateral complex is not supported from a developmental point of view

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

[Pneumococcal vaccine: protection of adults and reduction of antibiotic resistence by vaccination of children with a conjugated vaccine].

PubMed

Pletz, Mathias W

2011-06-01

Pneumococcal infections (pneumonia, otitis media, sinusitis, meningitis) are common and usually involve toddlers, immunocompromised and the elderly. Main reservoir of pneumococci is the nasopharyngeal zone of healthy carriers, especially of toddlers. Currently, two types of pneumococcal vaccines are in clinical use, which induce production of antibodies against capsular polysaccharides. The older vaccine consists of pure capsular polysaccharides. It induces a limited immunity, because polysaccharides are poor antigens that stimulate mainly B-cells. In children under two years of age this vaccine is not used, because it does not induce a sufficient immunologic response, presumably because of the immaturity of their immune system. In 2000, a vaccination program with a novel pneumococcal vaccine was launched in the USA. This vaccine contains capsular polysaccharides, that are conjugated with a highly immunogenic protein. It induces both a T cell and B cell response that results in specific humoral and mucosal immunity. U.S. data demonstrate, that serotypes covered by the conjugated vaccine can be reduced in the whole population by vaccination of children being the main reservoir of pneumococci. This so called ,,herd protection" results in a decrease in invasive pneumococcal diseases in vaccinees and non-vaccinees as well as in a reduction of antibiotic resistance rates by reducing resistant pneumococcal cones.

Isolation and structure elucidation of pectic polysaccharide from rose hip fruits (Rosa canina L.).

PubMed

Ognyanov, Manol; Remoroza, Connie; Schols, Henk A; Georgiev, Yordan; Kratchanova, Maria; Kratchanov, Christo

2016-10-20

A pectic polysaccharide from rose hip (RH) fruits has been obtained by extraction with 1% aqueous citric acid. It was found that the polysaccharide fraction mainly consisted of galacturonic acid (45.5%) next to galactose (5.5%) and arabinose (4.7%). RH pectin is having a relatively high degree of methylesterification (62%) and acetylation (10%) and consists of different molecular weight populations in the range of 10-100kDa. Enzymatic fingerprinting was performed using a combination of pectin lyase (PL) and endo-polygalacturonase. Detailed information about the structure and level of galacturonic acid oligomers released was obtained using LC-HILIC-MS/ELSD and HPAEC. Predominantly, unsaturated and methyl-esterified oligomers (DP 3-5) were released indicating that high proportions of methylesterified 'PL degradable' areas were present within the pectin. The data revealed that homogalacturonan is the main building block of the extracted pectin and consists of long methylesterified/acetylated GalA sequences interspersed with small blocks of non-methyl-esterified GalA units. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

PubMed

Kiho, T; Hui, J; Yamane, A; Ukai, S

1993-12-01

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

Understanding the bacterial polysaccharide antigenicity of Streptococcus agalactiae versus Streptococcus pneumoniae.

PubMed

Kadirvelraj, Renuka; Gonzalez-Outeiriño, Jorge; Foley, B Lachele; Beckham, Meredith L; Jennings, Harold J; Foote, Simon; Ford, Michael G; Woods, Robert J

2006-05-23

Bacterial surface capsular polysaccharides (CPS) that are similar in carbohydrate sequence may differ markedly in immunogenicity and antigenicity. The structural origin of these phenomena is poorly understood. Such a case is presented by the Gram-positive bacteria Streptococcus agalactiae (Group B Streptococcus; GBS) type III (GBSIII) and Streptococcus pneumoniae (Pn) type 14 (Pn14), which share closely related CPS sequences. Nevertheless, antibodies (Abs) against GBSIII rarely cross-react with the CPS from Pn14. To establish the origin for the variation in CPS antigenicity, models for the immune complexes of CPS fragments from GBSIII and Pn14, with the variable fragment (Fv) of a GBS-specific mAb (mAb 1B1), are presented. The complexes are generated through a combination of comparative Ab modeling and automated ligand docking, followed by explicitly solvated 10-ns molecular dynamics simulations. The relationship between carbohydrate sequence and antigenicity is further quantified through the computation of interaction energies using the Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) method, augmented by conformational entropy estimates. Despite the electrostatic differences between Pn14 and GBSIII CPS, analysis indicates that entropic penalties are primarily responsible for the loss of affinity of the highly flexible Pn14 CPS for mAb 1B1. The similarity of the solution conformation of the relatively rigid GBSIII CPS with that in the immune complex characterizes the previously undescribed 3D structure of the conformational epitope. The analysis provides a comprehensive interpretation for a large body of biochemical and immunological data related to Ab recognition of bacterial polysaccharides and should be applicable to other Ab-carbohydrate interactions.

Relatedness of the O-polysaccharide structures of Escherichia coli O123 and Salmonella enterica O58, both containing 4,6-dideoxy-4-{N-[(S)-3-hydroxybutanoyl]-D-alanyl}amino-D-glucose; revision of the E. coli O123 O-polysaccharide structure.

PubMed

Perepelov, Andrei V; Liu, Bin; Shevelev, Sergei D; Senchenkova, Sof'ya N; Shashkov, Alexander S; Feng, Lu; Knirel, Yuriy A; Wang, Lei

2010-04-19

O-Polysaccharides were isolated by mild acid degradation of the lipopolysaccharides of Escherichia coli O123 and Salmonella enterica O58 and studied by chemical methods and 2D (1)H and (13)C NMR spectroscopy, including experiments in a H(2)O/D(2)O mixture, which enabled observation of correlations for nitrogen-linked protons. The following structure of the O-polysaccharide of E. coli O123 was established: -->3)-beta-D-Quip4NAlaHb-(1-->6)-alpha-D-GlcpNAc-(1-->3)-alpha-L-QuipNAc-(1-->3)-alpha-D-Glcp (6)(approx. 30% OAc)NAc-(1--> where L-QuipNAc stands for 2-acetamido-2,6-dideoxy-L-glucose and D-Qui4NAlaHb for 4-{N-[(S)-3-hydroxybutanoyl]-D-alanyl}amino-4,6-dideoxy-D-glucose. The latter was isolated as an ethylene glycol glycoside by three sequential Smith degradations of the O-deacetylated O-polysaccharide. The structure established in this work is at variance with the E. coli O123-polysaccharide structure reported earlier [Clark, C. G.; Kropinski, A. M.; Parolis, H.; Grant, C. C.; Trout-Yakel, K. M.; Franklin, K.; Ng, L. K.; Paramonov, N. A.; Parolis, L. A.; Rahn, K.; Tabor, H. J. Med. Microbiol.2009, 58, 884-894]. In accordance with the genetic data, the O-polysaccharide of S. enterica O58 has the same structure, except for it lacks the O-acetylation. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Polysaccharide capsule and sialic acid-mediated regulation promote biofilm-like intracellular bacterial communities during cystitis.

PubMed

Anderson, Gregory G; Goller, Carlos C; Justice, Sheryl; Hultgren, Scott J; Seed, Patrick C

2010-03-01

Uropathogenic Escherichia coli (UPEC) is the leading cause of urinary tract infections (UTIs). A murine UTI model has revealed an infection cascade whereby UPEC undergoes cycles of invasion of the bladder epithelium, intracellular proliferation in polysaccharide-containing biofilm-like masses called intracellular bacterial communities (IBC), and then dispersal into the bladder lumen to initiate further rounds of epithelial colonization and invasion. We predicted that the UPEC K1 polysaccharide capsule is a key constituent of the IBC matrix. Compared to prototypic E. coli K1 strain UTI89, a capsule assembly mutant had a fitness defect in functionally TLR4(+) and TLR4(-) mice, suggesting a protective role of capsule in inflamed and noninflamed hosts. K1 capsule assembly and synthesis mutants had dramatically reduced IBC formation, demonstrating the common requirement for K1 polysaccharide in IBC development. The capsule assembly mutant appeared dispersed in the cytoplasm of the bladder epithelial cells and failed to undergo high-density intracellular replication during later stages of infection, when the wild-type strain continued to form serial generations of IBC. Deletion of the sialic acid regulator gene nanR partially restored IBC formation in the capsule assembly mutant. These data suggest that capsule is necessary for efficient IBC formation and that aberrant sialic acid accumulation, resulting from disruption of K1 capsule assembly, produces a NanR-mediated defect in intracellular proliferation and IBC development. Together, these data demonstrate the complex but important roles of UPEC polysaccharide encapsulation and sialic acid signaling in multiple stages of UTI pathogenesis.

Arthroscopic therapy of recurrent anterior luxation of the shoulder by capsular repair.

PubMed

Landsiedl, F

1992-01-01

Sixty-five cases of recurrent anterior unidirectional dislocation of the shoulder were treated by arthroscopic capsular repair. In this approach, the arthroscope is inserted through a posterior portal. Using mostly an anterior portal, a 5-mm hole is drilled across the neck of the glenoid, between the 3 and 4 o'clock positions. A 5-mm working cannula is passed from the posterior portal into the joint. Mostly through the anterior portal, four to six retention U-sutures are placed in the labrum, the middle and inferior glenohumeral ligament, and the subscapularis tendon. A 25-cm-long, 2.0-mm K-wire with an eye is used. The sutures are pulled out posteriorly through the cannula and tied on the fascia of the infraspinatus muscle. The goal of the procedure is to reattach the detached labrum-ligament complex (LLC) and achieve a capsulorrhaphy in a medial-lateral and superior-inferior direction. There were nine redislocations during a follow-up period of 24-60 months (average, 35.3 months). Reasons for redislocation were (a) fewer than four sutures; (b) no sutures of the LLC; (c) placement of the drill hole in the top third of the glenoid; (d) nontraumatic dislocation; (e) no Bankart or Hill-Sachs lesion; (f) transverse tear of the LLC; or (g) technical errors. Redislocation was more common in male patients.

Capsular Outcomes After Pediatric Cataract Surgery Without Intraocular Lens Implantation: Qualitative Classification and Quantitative Measurement.

PubMed

Tan, Xuhua; Lin, Haotian; Lin, Zhuoling; Chen, Jingjing; Tang, Xiangchen; Luo, Lixia; Chen, Weirong; Liu, Yizhi

2016-03-01

The objective of this study was to investigate capsular outcomes 12 months after pediatric cataract surgery without intraocular lens implantation via qualitative classification and quantitative measurement.This study is a cross-sectional study that was approved by the institutional review board of Zhongshan Ophthalmic Center of Sun Yat-sen University in Guangzhou, China.Digital coaxial retro-illumination photographs of 329 aphakic pediatric eyes were obtained 12 months after pediatric cataract surgery without intraocular lens implantation. Capsule digital coaxial retro-illumination photographs were divided as follows: anterior capsule opening area (ACOA), posterior capsule opening area (PCOA), and posterior capsule opening opacity (PCOO). Capsular outcomes were qualitatively classified into 3 types based on the PCOO: Type I-capsule with mild opacification but no invasion into the capsule opening; Type II-capsule with moderate opacification accompanied by contraction of the ACOA and invasion to the occluding part of the PCOA; and Type III-capsule with severe opacification accompanied by total occlusion of the PCOA. Software was developed to quantitatively measure the ACOA, PCOA, and PCOO using standardized DCRPs. The relationships between the accurate intraoperative anterior and posterior capsulorhexis sizes and the qualitative capsular types were statistically analyzed.The DCRPs of 315 aphakic eyes (95.8%) of 191 children were included. Capsular outcomes were classified into 3 types: Type I-120 eyes (38.1%); Type II-157 eyes (49.8%); Type III-38 eyes (12.1%). The scores of the capsular outcomes were negatively correlated with intraoperative anterior capsulorhexis size (R = -0.572, P < 0.001), but no significant correlation with intraoperative posterior capsulorhexis size (R = -0.16, P = 0.122) was observed. The ACOA significantly decreased from Type I to Type II to Type III, the PCOA increased in size from Type I to Type II, and the PCOO increased

5-Acetamido-3,5-dideoxy-L-glycero-L-manno-non-2-ulosonic acid-containing O-polysaccharide from marine bacterium Pseudomonas glareae KMM 9500T.

PubMed

Kokoulin, Maxim S; Kalinovsky, Anatoly I; Romanenko, Lyudmila A; Mikhailov, Valery V

2018-05-22

The O-polysaccharide was isolated from the lipopolysaccharide of a marine bacterium Pseudomonas glareae KMM 9500 T and studied by chemical methods along with 1D and 2D 1 H and 13 C NMR spectroscopy including 1 H, 1 H-TOCSY, 1 H, 1 H-COSY, 1 H, 1 H-ROESY, 1 H, 13 C-HSQC and 1 H, 13 C-HMBC experiments. The O-polysaccharide was found to consist of linear tetrasaccharide repeating units constituted by D-glucuronic acid (D-GlcA), L-rhamnose (L-Rha), D-glucose (D-Glc) and 5-acetamido-7,9-O-[(S)-1-carboxyethylidene]-3,5-dideoxy-L-glycero-L-manno-non-2-ulosonic acid (Sug7,9(S-Pyr)), partially O-acetylated at position 8 (∼70%): →4)-α-D-GlcpA-(1→3)-β-L-Rhap-(1→4)-β-D-Glcp-(1→4)-β-Sugp8Ac(∼70%)7,9(S-Pyr)-(2→. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

Isolation, characterization and investigation of Plantago ovata husk polysaccharide as superdisintegrant.

PubMed

Pawar, Harshal; Varkhade, Chhaya

2014-08-01

Psyllium husk (Plantago ovata, Family: Plantaginaceae) contains a high proportion of hemicellulose, composed of a xylan backbone linked with arabinose, rhamnose, and galacturonic acid units (arabinoxylans). Polysaccharide was isolated from Psyllium husk using solvent precipitation method. The isolated polysaccharide was evaluated for various physicochemical parameters. The rheological behavior of polysaccharide (1% w/v in water) was studied using Brookfield viscometer. Polysaccharide derived from the husk of P. ovata was investigated as superdisintegrant in the fast dissolving tablets. Valsartan, an antihypertensive drug, was selected as a model drug. The tablets of Valsartan were prepared separately using different concentrations (1, 2.5, 5, 7.5% w/w) of isolated Plantago ovata (P. ovata) husk polysaccharide (Natural) and crospovidone as a synthetic superdisintegrant by direct compression method. The prepared tablets were evaluated for various pre-compression and post-compression parameters. The drug excipient interactions were characterized by FTIR studies. The formulation F4 containing7.5% polysaccharide showed rapid wetting time and disintegration time as compared to formulation prepared using synthetic superdisintegrant at the same concentration level. Hence batch F4 was considered as optimized formulation. The stability studies were performed on formulation F4. The disintegration time and in vitro drug release of the optimized formulation was compared with the marketed formulation (Conventional tablets). Copyright © 2014 Elsevier B.V. All rights reserved.

First two cases of severe multifocal infections caused by Klebsiella pneumoniae in Switzerland: characterization of an atypical non-K1/K2-serotype strain causing liver abscess and endocarditis.

PubMed

Babouee Flury, Baharak; Donà, Valentina; Buetti, Niccolò; Furrer, Hansjakob; Endimiani, Andrea

2017-09-01

We describe the first two multifocal invasive infections due to Klebsiella pneumoniae recently observed in Switzerland. Phenotypic (MIC assays and string test) and molecular analyses (PCR/Sequencing for bla, virulence factor genes and whole genome sequencing for one strain) were performed to characterize the causative K. pneumoniae isolates. Both K. pneumoniae isolates (Kp1 and Kp2) were pan-susceptible to antibiotics and produced narrow-spectrum SHV β-lactamases. However, only Kp1 was string test positive. Kp1 was of ST380 and caused liver abscess as well as pneumonia and orbital phlegmon in an Eritrean patient. It belonged to the hypervirulent capsular serotype K2 and harboured the classic virulence-associated rmpA and aerobactin genes, fulfilling both the clinical and microbiological definitions for an invasive K. pneumoniae syndrome. Kp2 was of ST1043 and caused both liver abscess and endocarditis in a Swiss patient. Moreover, it did not possess the classic virulence-associated genes. Whole genome sequencing identified less well-known virulence factors in Kp2 that might have contributed to its virulence. Among these there were genes important for intestinal colonization and/or invasion, such as genes involved in adhesion (e.g., fimABCD and mrkABCD), regulation of capsule polysaccharide biosynthesis (e.g., evgS-evgA), as well as iron uptake (iroN), energy conversion, and metabolism. This report confirms the continuous dissemination of hypervirulent K. pneumoniae strains among patients of non-Asian descent in Europe. Moreover, it highlights the genetic background of an atypical hypervirulent K. pneumoniae causing a severe invasive infection despite not possessing the classical virulence characteristics of hypermucoviscous strains. Copyright © 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

Anticancer polysaccharides from natural resources: a review of recent research.

PubMed

Zong, Aizhen; Cao, Hongzhi; Wang, Fengshan

2012-11-06

Taking into account the rising trend of the incidence of cancers of various organs, effective therapies are urgently needed to control human malignancies. However, almost all of the chemotherapy drugs currently on the market cause serious side effects. Fortunately, several previous studies have shown that some non-toxic biological macromolecules, including polysaccharides and polysaccharide-protein complexes, possess anti-cancer activities or can increase the efficacy of conventional chemotherapy drugs. Based on these encouraging observations, a great deal of effort has been focused on discovering anti-cancer polysaccharides and complexes for the development of effective therapeutics for various human cancers. This review focuses on the advancements in the anti-cancer efficacy of various natural polysaccharides and polysaccharide complexes in the past 5 years. Most polysaccharides were tested using model systems, while several involved clinical trials. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of Vaccines to Prevent Wound Infections Due to Anerobic Bacteria

DTIC Science & Technology

1981-09-01

lot variability of the monosaccharide constituents 4 IV. Safety and toxicity testing of Lot 1 of polysaccharide antigens from B. fragilis strains 9343...the polysaccharide into monosac- charides followed by conversion of these to alditol acetates demonstrates several interesting monosaccharides present...rats with the capsular polysaccharide of B. fragilis iniuces protection to subsequent challenge with this organism. We have prpviously shown that in

Human monoclonal macroglobulins with specificity for Klebsiella K polysaccharides that contain 3,4-pyruvylated-D-galactose and 4,6- pyruvylated-D-galactose

PubMed Central

1980-01-01

Two human IgM myeloma proteins, IgMWEA and IgMMAY, were found to react with agar and Klebsiella polysaccharides that contain pyruvylated D- galactose (DGal). Quantitative precipitin data and precipitin inhibition studies with methyl alpha- and beta-glycosides of 4,6- pyruvylated-D-galactose showed their combining sites to be different, although each was directed against the pyruvylated-D-Gal, one reacting most specifically with Klebsiella polysaccharides with terminal nonreducing beta-linked 2,4 pyruvylated-D-Gal, whereas the other reacted equally well with Klebsiella polysaccharides that contain 3,4 beta-linked and 4,6 alpha-linked terminal nonreducing pyruvylated-DGal. Inhibition studies showed that both sites are directed toward one of the two space isomers of 3,4- or 4,6-pyruvylated DGal, the form in which the methyl group of the pyruvate is equatorial, or endo, and its carboxyl group axial, or exo, to the plane of the acetal ring. Coprecipitation studies showed the combining site of IgMWEA to be located on an (Fab')2 fragment and not on the (Fc)5mu fragment. The monoclonal peak in the serum of IgMMAY was specifically precipitated by Klebsiella polysaccharide. Myeloma proteins with specificities of this type may occur with reasonable frequency in humans and may be a consequence of clonal expansion from inapparent infection, carrier states, or disease produced by various Klebsiella organisms. PMID:6158553

Extraction, purification, characterization and antioxidant activities of polysaccharides from Cistanche tubulosa.

PubMed

Zhang, Wiejie; Huang, Jing; Wang, Wei; Li, Qian; Chen, Yao; Feng, Weiwei; Zheng, Daheng; Zhao, Ting; Mao, Guanghua; Yang, Liuqing; Wu, Xiangyang

2016-12-01

An efficient ultrasonic-cellulase-assisted extraction (UCE) of Cistanche tubulosa polysaccharide (CTP) was established. The response surface methodology based on Box-Behnken Design was employed to further optimize extraction conditions. After quaternary ammonium salt precipitation, the polysaccharide of C. tubulosa was characterized by different techniques. The results showed that a maximum polysaccharide yield of 22.31±0.45% was achieved at a pH of 5.2 for 31.5min at 54.1°C. Compared to hot water extraction, the yield of CTP in UCE and polysaccharide content increased to 44.96% and 70.13±2.19%, respectively. There was no marked difference among polysaccharides extracted using different methods from the infrared spectrum. Ultrasonic-cellulase-assisted extraction polysaccharide showed a fibrous structure from scanning electron microscopy and was composed of rhamnose, mannose, glucose, and galactose in a molar ratio of 2.18:1:28.29:1.43 by gas chromatography. The circular dichroism results indicated that polysaccharides had a maximum positive peak around 210nm with different peak values. The thermogravimetric analysis and differential scanning calorimetry were used to test the thermostability of CTP. Besides, CTP demonstrated appreciable antioxidant potential on antioxidant experiments in vitro. The results suggested that UCE is an effective method for CTP extraction and its polysaccharide showed appreciable antioxidant activity. Copyright © 2016 Elsevier B.V. All rights reserved.

Surgical management of spontaneous in-the-bag intraocular lens and capsular tension ring complex dislocation.

PubMed

Gunenc, Uzeyir; Kocak, Nilufer; Ozturk, A Taylan; Arikan, Gul

2014-08-01

We describe a technique to manage late spontaneous intraocular lens (IOL) and capsular tension ring (CTR) dislocation within the intact capsular bag. The subluxated IOL and CTR complex can be positioned in a closed chamber and fixed to the pars plana at both 3 and 9 o'clock quadrants with the presented ab externo direct scleral suturation technique which provides an easy, safe and effective surgical option for such cases.

In vitro and in vivo anti-inflammatory activities of high molecular weight sulfated polysaccharide; containing fucose separated from Sargassum horneri: Short communication.

PubMed

Sanjeewa, K K Asanka; Fernando, I P S; Kim, Seo-Young; Kim, Hyun-Soo; Ahn, Ginnae; Jee, Youngheun; Jeon, You-Jin

2018-02-01

Recent studies on crude and pure compounds from Sargassum horneri have shown promising bioactive properties. However, anti-inflammatory potentials of fucose-rich sulfated polysaccharides from S. horneri have not yet been discovered. In the present study, we evaluated the in vitro and in vivo anti-inflammatory activities of four polysaccharide fractions separated from membrane filters according to their molecular weights (<5kDa (f1), 5-10kDa (f2), 10-30kDa (f3), and >30kDa (f4)). According to the results, F4 fraction inhibited the lipopolysaccharides (LPS)-induced nitric oxide (NO) (IC 50 =87.12μg/mL) and prostaglandin E 2 production as well as pro-inflammatory cytokine production in RAW 264.7 cells through down-regulating nuclear factor-κB signaling cascade. According to the results, f4 has a potential to down-regulate LPS-induced toxicity, cell death and NO production levels in LPS-induced in vivo zebrafish embryo model. These results suggest that f4 fraction has the potential to develop functional materials or drugs to treat inflammatory diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

The influence of injection volume and capsular bag contraction on the refractive power of polymer refilled lenses - a finite element modelling simulation study.

PubMed

Martin, Heiner; Guthoff, Rudolf; Schmitz, Klaus-Peter

2011-09-01

Polymer injection into the capsular bag after phakoemulsification is an interesting and promising approach to lens surgery. Safe clinical application of this technique will require an appropriate estimate of the effect of implantation variables on the lens power. This article details the results of finite element investigations into the effects of the injected polymer volume and capsular bag contraction on the resultant lens power and accommodation amplitude. An axisymmetric finite element model was created from literature sources. Polymer injection and the capsular contraction were simulated, and their effect on the lens power was calculated. The simulations show that overfilling during polymer injection leads to a refractive power increase of the lens. Capsular bag contraction also results in a power increase. The calculated accommodative amplitude of the lens is minimally affected by capsular bag contraction but decreases significantly with increased capsular bag stiffness as a result of fibrosis. © 2010 The Authors. Journal compilation © 2010 Acta Ophthalmol.

Value of allohaemagglutinins in the diagnosis of a polysaccharide antibody deficiency

PubMed Central

Schaballie, H; Vermeulen, F; Verbinnen, B; Frans, G; Vermeulen, E; Proesmans, M; De Vreese, K; Emonds, MP; De Boeck, K; Moens, L; Picard, C; Bossuyt, X; Meyts, I

2015-01-01

Polysaccharide antibody deficiency is characterized by a poor or absent antibody response after vaccination with an unconjugated pneumococcal polysaccharide vaccine. Allohaemagglutinins (AHA) are antibodies to A or B polysaccharide antigens on the red blood cells, and are often used as an additional or alternative measure to assess the polysaccharide antibody response. However, few studies have been conducted to establish the clinical significance of AHA. To investigate the value of AHA to diagnose a polysaccharide antibody deficiency, pneumococcal polysaccharide antibody titres and AHA were studied retrospectively in 180 subjects in whom both tests had been performed. Receiver operating characteristic curves for AHA versus the pneumococcal vaccine response as a marker for the anti-polysaccharide immune response revealed an area under the curve between 0·5 and 0·573. Sensitivity and specificity of AHA to detect a polysaccharide antibody deficiency, as diagnosed by vaccination response, were low (calculated for cut-off 1/4–1/32). In subjects with only low pneumococcal antibody response, the prevalence of bronchiectasis was significantly higher than in subjects with only low AHA (45·5 and 1·3%, respectively) or normal pneumococcal antibody response and AHA (2·4%). A logistic regression model showed that low pneumococcal antibody response but not AHA was associated with bronchiectasis (odds ratio 46·2). The results of this study do not support the routine use of AHA to assess the polysaccharide antibody response in patients with suspected immunodeficiency, but more studies are warranted to clarify the subject further. PMID:25516411

Peptide mimotopes of complex carbohydrates in Salmonella enterica serovar typhi which react with both carbohydrate-specific monoclonal antibody and polyclonal sera from typhoid patients.

PubMed

Thong, Kwai-Lin; Tang, Swee-Seong; Tan, Wen-Siang; Devi, Shamala

2007-01-01

Polyclonal sera from typhoid patients and a monoclonal antibody, mAb ATVi, which recognizes the capsular polysaccharide Vi antigen (ViCPS), were used to select for peptides that mimic the ViCPS by using a phage-displayed random 12-mer peptide library. Two major common mimotopes selected from the library carried the amino acid sequences TSHHDSHGLHRV and ENHSPVNIAHKL. Enzyme-linked immunosorbent assays (ELISAs) showed that these peptides carry mimotopes to ViCPS. Phage clones that contained the 12-mer peptides were also tested against pooled/individual typhoid patients' sera and found to have 3 to 5 times higher binding compared to normal sera. By using Phage-ELISA assays, the derived synthetic peptides, TSHHDSHGLHRV and ENHSPVNIAHKL, were tested against a monoclonal antibody mAb ATVi and over 2-fold difference in binding was found between these peptides and a control unrelated peptide, CTLTTKLYC. Inhibition of the mAb's binding to ViCPS indicated that the synthetic peptides successfully competed with the capsular polysaccharide for antibody binding.

DNA-Sequence Based Typing of the Cronobacter Genus Using MLST, CRISPR-cas Array and Capsular Profiling

PubMed Central

Ogrodzki, Pauline; Forsythe, Stephen J.

2017-01-01

The Cronobacter genus is composed of seven species, within which a number of pathovars have been described. The most notable infections by Cronobacter spp. are of infants through the consumption of contaminated infant formula. The description of the genus has greatly improved in recent years through DNA sequencing techniques, and this has led to a robust means of identification. However some species are highly clonal and this limits the ability to discriminate between unrelated strains by some methods of genotyping. This article updates the application of three genotyping methods across the Cronobacter genus. The three genotyping methods were multilocus sequence typing (MLST), capsular profiling of the K-antigen and colanic acid (CA) biosynthesis regions, and CRISPR-cas array profiling. A total of 1654 MLST profiled and 286 whole genome sequenced strains, available by open access at the PubMLST Cronobacter database, were used this analysis. The predominance of C. sakazakii and C. malonaticus in clinical infections was confirmed. The majority of clinical strains being in the C. sakazakii clonal complexes (CC) 1 and 4, sequence types (ST) 8 and 12 and C. malonaticus ST7. The capsular profile K2:CA2, previously proposed as being strongly associated with C. sakazakii and C. malonaticus isolates from severe neonatal infections, was also found in C. turicensis, C. dublinensis and C. universalis. The majority of CRISPR-cas types across the genus was the I-E (Ecoli) type. Some strains of C. dublinensis and C. muytjensii encoded the I-F (Ypseudo) type, and others lacked the cas gene loci. The significance of the expanding profiling will be of benefit to researchers as well as governmental and industrial risk assessors. PMID:29033918

Rotationally asymmetric multifocal IOL implantation with and without capsular tension ring: refractive and visual outcomes and intraocular optical performance.

PubMed

Alió, Jorge L; Plaza-Puche, Ana B; Piñero, David P

2012-04-01

To ascertain whether the refractive, visual, and intraocular optical quality outcomes of a rotationally asymmetric multifocal intraocular lens (IOL) are enhanced by the use of a capsular tension ring. Ninety consecutive eyes from 53 patients (age range: 36 to 82 years) were divided into two groups: the no ring group comprised 43 eyes implanted with the multifocal rotationally asymmetric Lentis Mplus LS-312 (Oculentis GmbH) without a capsular tension ring; and the ring group comprised 47 eyes with the same IOL with a capsular tension ring. Distance and near visual acuity and refractive outcomes were evaluated pre- and postoperatively. Contrast sensitivity, intraocular aberrations, and defocus curve were evaluated postoperatively. Significant postoperative differences between groups were found in sphere, spherical equivalent refraction, and near addition (P<.02). Regarding defocus curve, significantly better visual acuity was present in eyes with the capsular tension ring for intermediate vision conditions (P<.05). Intraocular aberrometry did not differ significantly between groups (P<.09). Refractive predictability and intermediate visual outcomes with the Lentis Mplus LS-312 IOL improved significantly when implanted in combination with a capsular tension ring. Copyright 2012, SLACK Incorporated.

Mediating chemical reactions using polysaccharides

NASA Astrophysics Data System (ADS)

Tyler, Lauren E.

We have studied the NaBH4-mediated hydrogenation of select alkenes catalyzed by polysaccharide-stabilized nanoparticles. We compared the catalytic properties of Ni-based nanoparticles or Au/Co-based nanoparticles on the hydrogenation of cinnamic acid, cinnamide, cinnamyl alcohol, and ethyl cinnamate. We evaluated the possibility that the type of stabilizing polysaccharide surrounding the nanoparticle may affect the selectivity towards the alkene compounds that undergo the hydrogenation reaction. We found that the hydrogenation of cinnamide or ethyl cinnamate proceeded readily to 100% completion independent of the type of polysaccharide stabilizing the nanoparticle. However, the extent of the hydrogenation of cinnamyl alcohol and cinnamic acid varied greatly depending on the type of polysaccharide stabilizing the nanoparticle. In the course of these studies, we observed that some polysaccharides by themselves promoted the hydrolysis of ethyl cinnamate. Thus, we have raised the hypothesis that some polysaccharides may act as "esterases" and explored the interaction between select polysaccharides and a variety of ester compounds.

Methyl 3-O-α-l-fucopyranosyl β-d-glucopyran­oside tetra­hydrate

PubMed Central

Eriksson, Lars; Widmalm, Göran

2012-01-01

The title compound, C13H24O10·4H2O, is the methyl glycoside of a disaccharide structural element present in the backbone of the capsular polysaccharide from Klebsiella K1, which contains only three sugars and a substituent in the polysaccharide repeating unit. The conformation of the title disaccharide is described by the glycosidic torsion angles ϕH = 51.1 (1)° and ψH = 25.8 (1)°. In the crystal, a number of O—H⋯O hydrogen bonds link the methyl glycoside and water mol­ecules, forming a three-dimensional network. One water mol­ecule is disordered over two positions with occupancies of 0.748 (4) and 0.252 (4). PMID:23284493

USSR Report, Life Sciences, Biomedical and Behavioral Sciences

DTIC Science & Technology

1985-02-13

characterizing the geometry of the main polysaccharide chain were close to 180°, indicating that the C-C and C-0 bonds of adjacent monosaccharide moieties...Containing Copolymers With Streptococcus Pneumoniae Type 3 Capsular Polysaccharide Specificity (A. Ya. Chernyak, et al.; BIOORGANICHESKAYA KHIMIYA, No... Polysaccharides (N.■ F. Yankina, et al.; BIOORGANICHESKAYA KHIMIYA, No 10, Oct 84) .. 26 LASER EFFECTS Effects of Laser irradiation on Inflammation and

Polysaccharide-Modified Synthetic Polymeric Biomaterials

PubMed Central

Baldwin, Aaron D.; Kiick, Kristi L.

2010-01-01

This review presents an overview of polysaccharide-conjugated synthetic polymers and their use in tissue-engineered scaffolds and drug-delivery applications. This topic will be divided into four categories: (1) polymeric materials modified with non-mammalian polysaccharides such as alginate, chitin, and dextran; (2) polymers modified with mammalian polysaccharides such as hyaluronan, chondroitin sulfate, and heparin; (3) multi-polysaccharide-derivatized polymer conjugate systems; and (4) polymers containing polysaccharide-mimetic molecules. Each section will discuss relevant conjugation techniques, analysis, and the impact of these materials as micelles, particles, or hydrogels used in in-vitro and in-vivo biomaterial applications. PMID:20091875

Pneumococcal Capsules and Their Types: Past, Present, and Future

PubMed Central

Geno, K. Aaron; Gilbert, Gwendolyn L.; Song, Joon Young; Skovsted, Ian C.; Klugman, Keith P.; Jones, Christopher; Konradsen, Helle B.

2015-01-01

SUMMARY Streptococcus pneumoniae (the pneumococcus) is an important human pathogen. Its virulence is largely due to its polysaccharide capsule, which shields it from the host immune system, and because of this, the capsule has been extensively studied. Studies of the capsule led to the identification of DNA as the genetic material, identification of many different capsular serotypes, and identification of the serotype-specific nature of protection by adaptive immunity. Recent studies have led to the determination of capsular polysaccharide structures for many serotypes using advanced analytical technologies, complete elucidation of genetic basis for the capsular types, and the development of highly effective pneumococcal conjugate vaccines. Conjugate vaccine use has altered the serotype distribution by either serotype replacement or switching, and this has increased the need to serotype pneumococci. Due to great advances in molecular technologies and our understanding of the pneumococcal genome, molecular approaches have become powerful tools to predict pneumococcal serotypes. In addition, more-precise and -efficient serotyping methods that directly detect polysaccharide structures are emerging. These improvements in our capabilities will greatly enhance future investigations of pneumococcal epidemiology and diseases and the biology of colonization and innate immunity to pneumococcal capsules. PMID:26085553

Production of a unique pneumococcal capsule serotype belonging to serogroup 6

PubMed Central

Bratcher, Preston E.; Park, In H.; Hollingshead, Susan K.; Nahm, Moon H.

2013-01-01

Serogroup 6 of Streptococcus pneumoniae contains three serotypes named 6A, 6B and 6C with highly homologous capsule gene loci. The 6A and 6B capsule gene loci consistently differ from each other by only one nucleotide in the wciP gene. The 6A capsule gene locus has a galactosyl transferase, which has been replaced with a glucosyl transferase in the 6C capsule gene locus. We considered that a new serotype named “6X1” would be possible if the galactosyl transferase of the 6B capsule gene locus is replaced with the glucosyl transferase of 6C. We demonstrate that this gene transfer yields a viable pneumococcal strain and the capsular polysaccharide from this strain has the predicted chemical structure and serologic similarity to the capsular polysaccharide of the 6B serotype. The new strain (i.e., serotype 6X1) is typed as 6B by the quellung reaction but it can be distinguished from 6B strains with monoclonal antibodies to 6B polysaccharide. Reexamination of 264 pneumococcal isolates that were previously typed as 6B with classical typing methods revealed no isolates expressing serotype 6X1. Nevertheless, this study shows this capsular polysaccharide is biochemically possible and could exist/emerge in nature. PMID:19202106

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.

Gastroresistant capsular device prepared by injection molding.

PubMed

Zema, Lucia; Loreti, Giulia; Melocchi, Alice; Maroni, Alessandra; Palugan, Luca; Gazzaniga, Andrea

2013-01-20

In the present work, the possibility of manufacturing by injection molding (IM) a gastro-resistant capsular device based on hydroxypropyl methyl cellulose acetate succinate (HPMCAS) was investigated. By performing as an enteric soluble container, such a device may provide a basis for the development of advantageous alternatives to coated dosage forms. Preliminarily, the processability of the selected thermoplastic polymer was evaluated, and the need for a plasticizer (polyethylene glycol 1500) in order to counterbalance the glassy nature of the molded items was assessed. However, some critical issues related to the physical/mechanical stability (shrinkage and warpage) and opening time of the device after the pH change were highlighted. Accordingly, an in-depth formulation study was carried out taking into account differing release modifiers potentially useful for enhancing the dissolution/disintegration rate of the capsular device at intestinal pH values. Capsule prototypes with thickness of 600 and 900 μm containing Kollicoat(®) IR and/or Explotab(®) CLV could be manufactured, and a promising performance was achieved with appropriate gastric resistance in pH 1.2 medium and break-up in pH 6.8 within 1h. These results would support the design of a dedicated mold for the development of a scalable manufacturing process. Copyright © 2012 Elsevier B.V. All rights reserved.

Structural characterization of alkali-soluble polysaccharides from Panax ginseng C. A. Meyer

PubMed Central

Ji, Li; Jie, Zhenjing; Ying, Xin; Yue, Qi; Zhou, Yifa

2018-01-01

Panax ginseng C. A. Meyer (ginseng) has been widely used as a herb and functional food in the world. Polysaccharides are the main active components of ginseng. In this paper, the polysaccharides were sequentially extracted by 50 mM Na2CO3, 1 M KOH and 4 M KOH from ginseng roots treated sequentially with hot water, α-amylase and ethylenediaminetetraacetic acid extraction. Na2CO3-soluble ginseng polysaccharide (NGP) was fractionated into one neutral and three acidic fractions by anion exchange and gel permeation chromatography. Fourier transform infrared, NMR and methylation analysis indicated acidic fractions in NGP were highly branched rhamnogalacturonan-I domains, with  → 4)-α-GalpA-(1 → 2)-α-Rhap-(1 → disaccharide repeating units as backbone and β-1,4-galactan, α-1,5/1,3,5-arabinan and type II arabinogalactan as side chains. 1-KGP (1 M KOH-soluble ginseng polysaccharide) and 4-KGP (4 M KOH-soluble ginseng polysaccharide) were mainly composed of hemicellulose besides starch-like polysaccharides and minor pectin. Antibody detection, enzymic hydrolysis, high performance anion exchange chromatography and methylation analysis demonstrated xylan was the major component in 1-KGP, while xyloglucan was predominant in 4-KGP. Comparing the polysaccharides obtained by different solvent extractions, we have a comprehensive understanding about total ginseng polysaccharides. PMID:29657770

Molecular epidemiology of Klebsiella pneumoniae K1 and K2 isolates in Japan.

PubMed

Harada, Sohei; Ishii, Yoshikazu; Saga, Tomoo; Aoki, Kotaro; Tateda, Kazuhiro

2018-03-20

Although severe infections caused by hypervirulent Klebsiella pneumoniae isolates, such as K1 isolates belonging to sequence type (ST) 23, have been a significant problem in Asian countries, epidemiology of these isolates in Japan remains unclear. We performed a nationwide molecular epidemiological study of K. pneumoniae K1 and K2 isolates in Japan. Of the 259K. pneumoniae isolates collected, 14 and 16 isolates were identified as capsular genotypes K1 and K2, respectively. All K1 isolates were ST23 or its closely related clones and showed high genetic similarity by pulsed-field gel electrophoresis (PFGE) and the DiversiLab system (DL). K2 isolates, belonging to ST14, ST25, ST65, ST86, and ST110, were more genetically diverse than K1 isolates. Isolates belonging to a specific ST showed identical virulence gene profiles with a few exceptions. PFGE and DL results using K1 and K2 isolates were generally in agreement. Copyright © 2018. Published by Elsevier Inc.

Optimized Extraction of Polysaccharides from Grateloupia livida (Harv.) Yamada and Biological Activities.

PubMed

Ye, Danyan; Jiang, Zebin; Zheng, Fuchun; Wang, Hongmei; Zhang, Yanmei; Gao, Fenfei; Chen, Peihong; Chen, Yicun; Shi, Ganggang

2015-09-16

Polysaccharides from Grateloupia livida (Harv.) Yamada (GL) were extracted by a heating circumfluence method. Single-factor experiments were performed for the three parameters: extraction time (X₁), extraction temperature (X₂) and the ratio of water to raw material (X₃) and their test range. From preliminary experimental results, one type of the response surface methodology, the Box-Behnken design was applied for the optimizing polysaccharide extraction conditions. The experimental data obtained were fitted to a second-order polynomial equation. The optimal conditions were extraction time 5 h, extraction temperature 100 °C and ratio of water to raw material 70 mL/g. Under these conditions, the experimental yield was 39.22% ± 0.09%, which well matched the predicted value (39.25%), with 0.9774 coefficient of determination (R²). GL polysaccharides had scavenging activities for DPPH and hydroxyl radicals in vitro. The scavenging rates for both radicals peaked at 20 mg/mL GL concentration. However, the positive standard, VC (ascorbic acid), possessed stronger antioxidant activities than GL polysaccharides. Furthermore, the anticancer activity of GL polysaccharides on HepG2 cell proliferation increased dose- and time-dependently, but the positive standard, 5-fluorouracil (5-fu) showed more significant anticancer activity in this study. Overall, GL polysaccharides may have potential applications in the medical and food industries.

HPAEC-PAD quantification of Haemophilus influenzae type b polysaccharide in upstream and downstream samples.

PubMed

van der Put, Robert M F; de Haan, Alex; van den IJssel, Jan G M; Hamidi, Ahd; Beurret, Michel

2015-11-27

Due to the rapidly increasing introduction of Haemophilus influenzae type b (Hib) and other conjugate vaccines worldwide during the last decade, reliable and robust analytical methods are needed for the quantitative monitoring of intermediate samples generated during fermentation (upstream processing, USP) and purification (downstream processing, DSP) of polysaccharide vaccine components. This study describes the quantitative characterization of in-process control (IPC) samples generated during the fermentation and purification of the capsular polysaccharide (CPS), polyribosyl-ribitol-phosphate (PRP), derived from Hib. Reliable quantitative methods are necessary for all stages of production; otherwise accurate process monitoring and validation is not possible. Prior to the availability of high performance anion exchange chromatography methods, this polysaccharide was predominantly quantified either with immunochemical methods, or with the colorimetric orcinol method, which shows interference from fermentation medium components and reagents used during purification. Next to an improved high performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD) method, using a modified gradient elution, both the orcinol assay and high performance size exclusion chromatography (HPSEC) analyses were evaluated. For DSP samples, it was found that the correlation between the results obtained by HPAEC-PAD specific quantification of the PRP monomeric repeat unit released by alkaline hydrolysis, and those from the orcinol method was high (R(2)=0.8762), and that it was lower between HPAEC-PAD and HPSEC results. Additionally, HPSEC analysis of USP samples yielded surprisingly comparable results to those obtained by HPAEC-PAD. In the early part of the fermentation, medium components interfered with the different types of analysis, but quantitative HPSEC data could still be obtained, although lacking the specificity of the HPAEC-PAD method. Thus, the HPAEC

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

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 ( M W ) 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 ( M W ) 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

Delayed splenic rupture: dating the sub-capsular hemorrhage as a useful task to evaluate causal relationships with trauma.

PubMed

Riezzo, Irene; Di Battista, Benedetta; De Salvia, Alessandra; Cantatore, Santina; Neri, Margherita; Pomara, Cristoforo; Turillazzi, Emanuela; Fineschi, Vittorio

2014-01-01

The aim of the paper was to perform a chronological assessment of the phenomenon of delayed rupture of the spleen, to assess the phenomenological order about the sub-capsular hematoma transformation to determine the causal relationship with trauma as hypothetical cause of death. 80 cases of blunt trauma with splenic capsular hematoma and subsequent rupture of the spleen were evaluated: 38 had an acute rupture of the spleen, 42 presented a break in days or weeks after the traumatic injury. Time between the traumatic event and delayed rupture of the spleen is within a range of time from one day to more than one month. Data recorded included age, sex, type of trauma, injury severity score, grade of splenic injury, associated intra-abdominal injuries, pathologic specimen evaluation. Immunohistochemical investigation of perisplenic hematoma or laceration was performed utilizing polyclonal antibodies anti-fibrinogen, CD61 and CD68, and showed structural chronological differences of sub-capsular hematoma. Expression of modification and organization of erythrocytes, fibrinogen, platelets and macrophages provides an informative picture of the progression of reparative phenomena associated with sub-capsular hematoma and subsequent delayed splenic rupture. Sub-capsular splenic hematoma dating, which we divided into 4 phases, is representing a task in both clinical practice and forensic pathology. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Polysaccharides as Alternative Moisture Retention Agents for Shrimp.

PubMed

Torti, Michael J; Sims, Charles A; Adams, Charles M; Sarnoski, Paul J

2016-03-01

Phosphates are used as moisture retention agents (MRAs) by the shrimp industry. Although they are effective, phosphates are expensive, need to be listed on a food label, and overuse can often lead to a higher product cost for consumers. Polysaccharides were researched as alternative MRAs. Polysaccharides are usually inexpensive, are considered natural, and can have nutritional benefits. Research was conducted to determine whether polysaccharides yielded similar functional impacts as phosphates. Treatments included a 0.5% fibercolloid solution isolated from citrus peel, an 8% pectin solution, a 0.5% xanthan gum (XG) solution, a 1% carboxymethyl cellulose solution, and conventionally used 4% sodium tripolyphosphate (STP). Experimental treatments were compared to a distilled water control to gauge effectiveness. Freezing, boiling, and oven drying studies were performed to determine how moisture retention in shrimp differed using these different treatments. Water activity was measured to determine any potential differences in shelf life. Solution uptake was also determined to understand how well the treatments enhanced water binding. For moisture loss by freezing, 4% STP and the 0.5% fibercolloid solution functioned the best. The 4% STP treated shrimp lost the least amount of moisture during boiling. The 0.5% fibercolloid and 0.5% XG treatment outperformed phosphates in respect to moisture uptake ability. None of the treatments had a major effect on water activity. All treatments were rated similar in consumer sensory acceptability tests except for pectin, which was rated lower by the sensory panel. Overall, polysaccharides were found to be viable alternatives to phosphates. © 2016 Institute of Food Technologists®

Investigation of vesicle-capsular plague antigen complex formation by elastic laser radiation scattering

NASA Astrophysics Data System (ADS)

Guseva, N. P.; Maximova, Irina S.; Romanov, Sergey V.; Shubochkin, L. P.; Tatarintsev, Sergey N.

1991-05-01

Recently a great deal of attention has been given to the investigation artificial lipid liposomes, due to their application as "containers" for directed transport of biologically active compounds into particular cells, organs and tissues for prophylaxis and therapy of infectious diseases. The use of traditional methods of liposome investigation, such as sedimentation, electrophoresis and chromatography is impeded by low liposome resistivity to different deformations. In conjunction with this, optical methods of laser light scattering are promising as they allow nondisturbing, precise and quick investigations. This paper describes the investigation of vesicle systems prepared from egg lecithin of Serva Corporation and their complexes with the capsular antigen of the plague microbe. The capsular antigen Fl was obtained from EV plague microbe grown at 37° C on Huttinger agar. Fl was isolated by gel-filtration on ASA-22 followed by freeze drying of the preparation. Angular dependences of polarized radiation scattering were measured for several liposome suspension samples in a saline solution before and after the interaction with the plague microbe capsular antigen. The aim of the investigation was to analyze the nature of mutual antigen arrangement in a liposome and to develop methods for measuring its inclusion percentage.

A quantitative ELISA for antigen-specific IgG subclasses using equivalence dilutions of anti-kappa and anti-subclass specific secondary reagents. Application to the study of the murine immune response against the capsular polysaccharide of Neisseria meningitidis serogroup B.

PubMed

Colino, J; Diez, M; Outschoorn, I

1996-04-19

We have developed an enzyme-linked immunosorbent assay (ELISA) to measure murine antigen-specific IgG antibodies of defined subclass using precalibrated equivalence dilutions of anti-kappa (in the standard) and each anti-IgG subclass-specific polyclonal secondary antibody (in the test sample). The calibration of secondary reagents could be carried out easily with a set of monoclonal antibodies (MoAbs) specific for all IgG subclasses. These MoAbs do not require purification or standardization. In addition the MoAbs can be of different antigenic specificity. Once the equivalence dilutions have been determined, they can be applied in a quantitative ELISA using the same antigen in the standard and sample, and using only one IgG subclass standard for the determination of all the IgG subclasses. The method is easy to standardize for many antigenic systems. It is particularly useful when the only standard available is one standardized MoAb of the appropriate specificity, and it could be adapted to use with standard polyclonal antibodies having a known content of total antigen-specific IgG bearing kappa chains but unknown IgG subclass composition. The use of this method to quantitate IgG specific for the capsular polysaccharide of Neisseria meningitidis serogroup B (CpsB) gave highly reproducible measures with an interbatch CV of 5-6% similar for all IgG subclasses and low detection limits ranging from 0.3 ng/well for IgG3 to 0.8 ng/well for IgG2a. The IgG subclass response observed after immunization with live meningococci was mainly IgG2a (74%) and IgG2b (18%). Hyperimmunization modified this IgG distribution to one of mainly IgG3 (62%) and IgG1 (28%) which was maintained in the response to a single immunization 4 weeks later, possibly indicating the generation of resting B cells during continuous stimulation.

Structural features of the exocellular polysaccharides of Mycobacterium tuberculosis.

PubMed Central

Lemassu, A; Daffé, M

1994-01-01

The cell envelope which surrounds pathogenic mycobacteria is postulated to be a defence barrier against phagocytic cells and its outermost constituents have a tendency to accumulate in the culture medium. The present work demonstrates that the exocellular material of Mycobacterium tuberculosis contains large amounts of polysaccharides with only traces, if any at all, of lipids. Three types of polysaccharides were purified by anion-exchange and gel-filtration chromatography; all were found to be neutral compounds devoid of acyl substituents. They consisted of D-glucan, D-arabino-D-mannan and D-mannan, which were eluted from gel-filtration columns in positions corresponding to molecular masses of 123, 13 and 4 kDa respectively. Their predominant structural features were determined by the characterization of the per-O-methyl derivatives of enzymic, acetolysis and Smith-degradation products and by 1H- and 13C-n.m.r. spectroscopy of the purified polysaccharides, using mono- and two-dimensional homonuclear chemical-shift correlated spectroscopy and two-dimensional heteronuclear (1H/13C) spectroscopy. The glucan which represented up to 90% of the polysaccharides was composed of repeating units of five or six-->4-alpha-D-Glcp-1--> residues and a -->4-alpha-D-Glcp substituted at position 6 with an alpha-D-Glcp, indicating a glycogen-like highly branched structure not related to the so-called polysaccharide-II previously identified in tuberculin. The arabinomannan consisted of a mannan segment composed of a -->6-alpha-D-Man-1--> core substituted at some positions 2 with an alpha-D-Manp. The arabinan termini of the arabinomannan were found to be extensively capped with mannosyl residues. The possibility that these polysaccharides contribute to the persistence of the tubercle bacillus in the macrophage by molecular mimicry is discussed. PMID:8297342

Structural features of the exocellular polysaccharides of Mycobacterium tuberculosis.

PubMed

Lemassu, A; Daffé, M

1994-01-15

The cell envelope which surrounds pathogenic mycobacteria is postulated to be a defence barrier against phagocytic cells and its outermost constituents have a tendency to accumulate in the culture medium. The present work demonstrates that the exocellular material of Mycobacterium tuberculosis contains large amounts of polysaccharides with only traces, if any at all, of lipids. Three types of polysaccharides were purified by anion-exchange and gel-filtration chromatography; all were found to be neutral compounds devoid of acyl substituents. They consisted of D-glucan, D-arabino-D-mannan and D-mannan, which were eluted from gel-filtration columns in positions corresponding to molecular masses of 123, 13 and 4 kDa respectively. Their predominant structural features were determined by the characterization of the per-O-methyl derivatives of enzymic, acetolysis and Smith-degradation products and by 1H- and 13C-n.m.r. spectroscopy of the purified polysaccharides, using mono- and two-dimensional homonuclear chemical-shift correlated spectroscopy and two-dimensional heteronuclear (1H/13C) spectroscopy. The glucan which represented up to 90% of the polysaccharides was composed of repeating units of five or six-->4-alpha-D-Glcp-1--> residues and a -->4-alpha-D-Glcp substituted at position 6 with an alpha-D-Glcp, indicating a glycogen-like highly branched structure not related to the so-called polysaccharide-II previously identified in tuberculin. The arabinomannan consisted of a mannan segment composed of a -->6-alpha-D-Man-1--> core substituted at some positions 2 with an alpha-D-Manp. The arabinan termini of the arabinomannan were found to be extensively capped with mannosyl residues. The possibility that these polysaccharides contribute to the persistence of the tubercle bacillus in the macrophage by molecular mimicry is discussed.

Boreal pollen contain ice-nucleating as well as ice-binding ‘antifreeze’ polysaccharides

NASA Astrophysics Data System (ADS)

Dreischmeier, Katharina; Budke, Carsten; Wiehemeier, Lars; Kottke, Tilman; Koop, Thomas

2017-02-01

Ice nucleation and growth is an important and widespread environmental process. Accordingly, nature has developed means to either promote or inhibit ice crystal formation, for example ice-nucleating proteins in bacteria or ice-binding antifreeze proteins in polar fish. Recently, it was found that birch pollen release ice-nucleating macromolecules when suspended in water. Here we show that birch pollen washing water exhibits also ice-binding properties such as ice shaping and ice recrystallization inhibition, similar to antifreeze proteins. We present spectroscopic evidence that both the ice-nucleating as well as the ice-binding molecules are polysaccharides bearing carboxylate groups. The spectra suggest that both polysaccharides consist of very similar chemical moieties, but centrifugal filtration indicates differences in molecular size: ice nucleation occurs only in the supernatant of a 100 kDa filter, while ice shaping is strongly enhanced in the filtrate. This finding may suggest that the larger ice-nucleating polysaccharides consist of clusters of the smaller ice-binding polysaccharides, or that the latter are fragments of the ice-nucleating polysaccharides. Finally, similar polysaccharides released from pine and alder pollen also display both ice-nucleating as well as ice-binding ability, suggesting a common mechanism of interaction with ice among several boreal pollen with implications for atmospheric processes and antifreeze protection.

Boreal pollen contain ice-nucleating as well as ice-binding ‘antifreeze’ polysaccharides

PubMed Central

Dreischmeier, Katharina; Budke, Carsten; Wiehemeier, Lars; Kottke, Tilman; Koop, Thomas

2017-01-01

Ice nucleation and growth is an important and widespread environmental process. Accordingly, nature has developed means to either promote or inhibit ice crystal formation, for example ice-nucleating proteins in bacteria or ice-binding antifreeze proteins in polar fish. Recently, it was found that birch pollen release ice-nucleating macromolecules when suspended in water. Here we show that birch pollen washing water exhibits also ice-binding properties such as ice shaping and ice recrystallization inhibition, similar to antifreeze proteins. We present spectroscopic evidence that both the ice-nucleating as well as the ice-binding molecules are polysaccharides bearing carboxylate groups. The spectra suggest that both polysaccharides consist of very similar chemical moieties, but centrifugal filtration indicates differences in molecular size: ice nucleation occurs only in the supernatant of a 100 kDa filter, while ice shaping is strongly enhanced in the filtrate. This finding may suggest that the larger ice-nucleating polysaccharides consist of clusters of the smaller ice-binding polysaccharides, or that the latter are fragments of the ice-nucleating polysaccharides. Finally, similar polysaccharides released from pine and alder pollen also display both ice-nucleating as well as ice-binding ability, suggesting a common mechanism of interaction with ice among several boreal pollen with implications for atmospheric processes and antifreeze protection. PMID:28157236

Sealing effect of a polysaccharide nanosheet for murine cecal puncture.

PubMed

Fujie, Toshinori; Kinoshita, Manabu; Shono, Satoshi; Saito, Akihiro; Okamura, Yosuke; Saitoh, Daizoh; Takeoka, Shinji

2010-07-01

Recent developments in nanobiotechnology have led us to develop a method of producing a free-standing polymer nanosheet composed of polysaccharides (ie, polysaccharide nanosheet) with a thickness of tens of nanometers. Owing to its enormous aspect ratio, the polysaccharide nanosheet is semi-absorbent and has a physical adhesive strength 7.5-fold greater than that of conventional films of >1 microm thickness. Herein, we have investigated the therapeutic sealing effect of this polysaccharide nanosheet on murine cecal puncture as a wound dressing material. Murine cecum was punctured and then overlapped with the polysaccharide nanosheet. Thereafter, we evaluated its sealing effect on bacterial peritonitis as well as the protection offered by the polysaccharide nanosheet against bacterial permeability using an in vitro transmembrane assay. The 39-nm-thick polysaccharide nanosheet overlapped tightly the perforated cecum. No adhering agents were required because of the ability of the polysaccharide nanosheet to adhere to the tissue surface by physical adsorption (eg, van der Waals interaction). Sealing the perforated cecum with the polysaccharide nanosheet increased survival rate without postoperative adhesion by comparison with untreated mice (90 vs 30%; P < .01). These data were supported by the improvement in peritonitis related to bacterial counts, white blood cell counts, and the serum tumor necrosis factor level. Moreover, using an in vitro transmembrane assay, we showed that the polysaccharide nanosheet inhibited effectively bacterial penetration. We have demonstrated the potential clinical benefits of the nanosheet-type biomaterial that can be used for repairing a cecal colotomy without chemical bonding agents. Copyright 2010 Mosby, Inc. All rights reserved.

Do textured breast implants decrease the rate of capsular contracture compared to smooth implants?

PubMed

Cifuentes, Ignacio; Dagnino, Bruno; Rada, Gabriel

2017-08-31

The use of breast implants for aesthetic and reconstructive purposes has become one of the most common procedures performed by plastic surgeons. Several breast implants models exist. They differ in their size, filling, shape and characteristic of the shell, which can be smooth or textured. Capsular contracture is one of the main complications of breast implants. It has been suggested that the use of textured implants could reduce the incidence of capsular contracture. To answer this question, we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We identified 15 studies overall, of which 13 were randomized trials relevant for the question of interest. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. We concluded the use of textured breast implants probably decreases the risk of capsular contracture, however, they might be associated to an increased risk of anaplastic large cell lymphoma.

Analysis of periprosthetic capsular tissue from women with silicone breast implants by magic-angle spinning NMR.

PubMed

Garrido, L; Young, V L

1999-09-01

The amount of silicone (polydimethylsiloxane [PDMS]) in capsular tissue surgically removed from women with breast implants was measured by using (29)Si and (1)H magic-angle spinning solid-state NMR spectroscopy. Twelve women having smooth surface silicone gel-filled implants, including a subject with "low-bleed" double-lumen implants, had detectable levels of PDMS ranging from 0. 05 to 9.8% silicon in wet tissue (w/w). No silicon-containing compounds other than PDMS were detected. No correlation was found between the amount of PDMS measured in the capsular tissue and the length of implantation time (Pearson correlation coefficient, r = 0. 22). The results showed no relationship between higher amounts of PDMS and capsular contracture (p = 0.74) or other symptoms (p = 0. 53). Magn Reson Med 42:436-441, 1999. Copyright 1999 Wiley-Liss, Inc.

Isolation of a polysaccharide with anticancer activity from Auricularia polytricha using high-speed countercurrent chromatography with an aqueous two-phase system.

PubMed

Song, Guanglei; Du, Qizhen

2010-09-17

Polysaccharides from a crude extract of Auricularia polytricha were separated by high-speed countercurrent chromatography (HSCCC). The separation was performed with an aqueous two-phase system of PEG1000-K2HPO4-KH2PO4-H2O (0.5:1.25:1.25:7.0, w/w). The crude sample (2.0 g) was successfully separated into three polysaccharide components of AAPS-1 (192 mg), AAPS-2 (137 mg), and AAPS-3 (98 mg) with molecular weights of 162, 259, and 483 kDa, respectively. These compounds were tested for growth inhibition of transplanted S180 sarcoma in mice. AAPS-2 had an inhibition rate of 40.4%. The structure of AAPS-2 was elucidated from partial hydrolysis, periodate oxidation, acetylation, methylation analysis, and NMR spectroscopy (1H, 13C). These results showed AAPS-2 is a polysaccharide with a backbone of (1-->3)-linked-beta-d-glucopyranosyl and (1-->3, 6)-linked-beta-D-glucopyranosyl residues in a 2:1 ratio, and has one terminal (1-->)-beta-D-glucopyranosyl at the O-6 position of (1-->3, 6)-linked-beta-D-glucopyranosyl of the main chain. 2010 Elsevier B.V. All rights reserved.

Lewis Y Antigen as a Target for Breast Cancer Therapy

DTIC Science & Technology

1996-09-01

have shown that a synthetic peptide can mimic the capsular polysaccharide of N. meningitis serogroup C (MCP) in that it induces an anti-MCP immune...intervening residue. All these sequences resemble the peptide we have identified as a mimic of the group C meningococcal polysaccharide . The immunological...Group C Polysaccharide ct(2-9)sialic acid The sequence similarities among the putative motifs suggest that antibodies raised to this peptide set might

Polysaccharides and food processing.

PubMed

Pilnik, W; Rombouts, F M

1985-10-01

The rôle of polysaccharides during processing and for the quality of foods is discussed. Starch is the most important energy source for man. Most other polysaccharides are not metabolized for energy, but play an important rôle as dietary fibres. Pectins, alginates, carrageenans, and galactomannans are discussed as functional food additives in relation to their structure and their rheological behaviour, stability and interactions. Endogenous polysaccharides of fruits and vegetables and in products derived from them are responsible for such phenomena as texture (changes), press yields, ease of filtration and clarification, cloud stability, and mouth feel. To achieve desirable properties, the action of endogenous enzymes on polysaccharides must be inactivated and/or exogenous enzymes added as processing aids. This is also true for overcoming haze phenomena in clear juices or to break down undesirable microbial polysaccharides. Dough properties for bread baking can be improved by enzymic breakdown of a restrictive pentoglycan network. Network formation may come about by oxidative coupling of phenol rings of ferulic acid bound to hemicelluloses by ester links. Gels may be made by inducing oxidative coupling in natural or synthetic systems. Stagnation in development of new polysaccharide food additives is ascribed to difficulties in obtaining government approval for food use.

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. Copyright © 2014 Elsevier Ltd. All rights reserved.

Structural analysis of a homogeneous polysaccharide from Achatina fulica.

PubMed

Liu, Jie; Shang, Feineng; Yang, Zengming; Wu, Mingyi; Zhao, Jinhua

2017-05-01

Edible snails have been widely used as a health food and medicine in many countries. In our study, a water-soluble polysaccharide (AF-1) was isolated and purified from Achatina fulica by papain enzymolysis, alcohol precipitation and strong anion exchange chromatography. Structureof the polysaccharide was analyzed and characterized by chemical and instrumental methods, such as Fourier transform infrared spectroscopy, high performance liquid chromatography, analysis of monosaccharide composition, methylation analysis, and nuclear magnetic resonance (NMR) spectroscopy ( 1 H, 13 C, COSY, TOCSY, NOESY, HSQC and HMBC). Chemical composition analysis indicated that AF-1 is composed of glucose (Glc) and its average molecular weight is 1710kDa. Structural analysis suggested that AF-1 is mainly consisted of a linear repeating backbone of (1→4) linked α-d-Glc p residues with one branch, α-d-Glc p, attached to the main chain by (1→6) glycosidic bonds at every five main-chain units. Further studies on biological activities of the polysaccharide are currently in progress. Copyright © 2017 Elsevier B.V. All rights reserved.

Polysaccharide-based antibiofilm surfaces.

PubMed

Junter, Guy-Alain; Thébault, Pascal; Lebrun, Laurent

2016-01-01

Surface treatment by natural or modified polysaccharide polymers is a promising means to fight against implant-associated biofilm infections. The present review focuses on polysaccharide-based coatings that have been proposed over the last ten years to impede biofilm formation on material surfaces exposed to bacterial contamination. Anti-adhesive and bactericidal coatings are considered. Besides classical hydrophilic coatings based on hyaluronic acid and heparin, the promising anti-adhesive properties of the algal polysaccharide ulvan are underlined. Surface functionalization by antimicrobial chitosan and derivatives is extensively surveyed, in particular chitosan association with other polysaccharides in layer-by-layer assemblies to form both anti-adhesive and bactericidal coatings. Bacterial contamination of surfaces, leading to biofilm formation, is a major problem in fields as diverse as medicine, first, but also food and cosmetics. Many prophylactic strategies have emerged to try to eliminate or reduce bacterial adhesion and biofilm formation on surfaces of materials exposed to bacterial contamination, in particular implant materials. Polysaccharides are widely distributed in nature. A number of these natural polymers display antibiofilm properties. Hence, surface treatment by natural or modified polysaccharides is a promising means to fight against implant-associated biofilm infections. The present manuscript is an in-depth look at polysaccharide-based antibiofilm surfaces that have been proposed over the last ten years. This review, which is a novelty compared to published literature, will bring well documented and updated information to readers of Acta Biomaterialia. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Naturally Acquired and Conjugate Vaccine-Induced Antibody to Haemophilus influenzae Type b (Hib) Polysaccharide in Malian Children: Serological Assessment of the Hib Immunization Program in Mali

PubMed Central

Hutter, Julia; Pasetti, Marcela F.; Sanogo, Doh; Tapia, Milagritos D.; Sow, Samba O.; Levine, Myron M.

2012-01-01

Haemophilus influenzae type b (Hib) conjugate vaccine for infants (6, 10, and 14 weeks of age) was introduced into the Malian Expanded Program on Immunization in July 2005, to diminish invasive Hib disease in young children. Antibodies to Hib capsular polysaccharide (PRP) were measured in infants and toddlers from an area already served by the Hib immunization program (Bamako) and in unimmunized children of the same age in a district (Kangaba) where Hib immunization had not yet begun. Among vaccinated Bamako children 6–23 months of age, 77–93% exhibited PRP titers ≥ 1.0 μg/mL, indicating long-term protection, versus only 10–23% of Kangaba children of that age. High PRP antibody titers in immunized children persisted through 2 years of age. Moreover, ∼50% of Bamako children exhibited anti-PRP titers ≥ 5.0 μg/mL; a level that impedes Hib upper respiratory carriage, and may thereby diminish the Hib transmission to the unimmunized susceptible population (i.e., providing indirect protection). PMID:22665612

Antiviral activity of polysaccharide extract from Laminaria japonica against respiratory syncytial virus.

PubMed

Cao, Yin-Guang; Hao, Yu; Li, Zhi-Hui; Liu, Shun-Tao; Wang, Le-Xin

2016-12-01

This study was designed to investigate the inhibition activity of polysaccharide extract from Laminaria japonica against RSV. The polysaccharide from Laminaria japonica was isolated by ethanol precipitation. HEK293 cells were infected with RVS, and the antiviral activity of polysaccharide extract against RSV in host cells was tested. By using ELISA and western blot assay, the expression level of IFN-α and IRF3 and their functional roles in polysaccharide-mediated antiviral activity against RSV were investigated. The polysaccharide extract from Laminaria japonica had low toxicity to HEK293 cell. The TC50 to HEK293 cells was up to 1.76mg/mL. Furthermore, the EC50 of polysaccharide extract to RSV was 5.27μg/mL, and TI was 334. The polysaccharide extract improved IRF-3 expression which promoted the level of IFN-α. Polysaccharide extract from Laminaria japonica elicits antiviral activity against RSV by up-regulation of IRF3 signaling-mediated IFN-α production. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Optimization of antioxidant and antiglycated activities of polysaccharides from Arthrocnemum indicum leaves.

PubMed

Mzoughi, Zeineb; Chaouch, Mohamed Aymen; Hammi, Khaoula Mkadmini; Hafsa, Jawhar; Le Cerf, Didier; Ksouri, Riadh; Majdoub, Hatem

2018-07-01

Central composite design was performed to optimize uronic acid rate, esterification degree, total antioxidant ability and antiglycation capacity of carbohydrates from Arthrocnemum indicum leaves. Three independent variables were opted: extraction temperature, time and ratio (solvent/material). The optimal settings were: extraction temperature of 80°C, time of 288min and (solvent/solid) ratio of 40mL/g. Under these settings, uronic acid rate and esterification degree were 49.29%, 30.24%, respectively, whereas total antioxidant activity and antiglycation capacity was 35.81mg ascorbic acid equivalents/g matter and 69.81%, respectively. Colorimetric assays showed that total sugar and uronic acid contents for polysaccharide were 71.78% and 49.24%, respectively. Furthermore, Preliminary structure study was performed via various methods including FT-IR, NMR and UV-vis analysis. SEC analyzes revealed that polysaccharide had an average molecular weight of 2179kDa. Moreover, GC-MS analyzes showed that extracted polysaccharide was a pectic polysaccharide which formed of arabinose, mannose, galactose, rhamnose, glucose and xylose in the molar percentage of 66.68%, 3.93%, 12.71%, 6.31%, 6.08% and 4.29%, respectively. This results revealed that extracted polysaccharide can be employed as source of natural antioxidants and as possible antiglycated agents. Copyright © 2018 Elsevier B.V. All rights reserved.

Endorectal MR imaging of prostate cancer: Evaluation of tumor capsular contact length as a sign of extracapsular extension.

PubMed

Mendez, Gustavo; Foster, Bryan R; Li, Xin; Shannon, Jackilen; Garzotto, Mark; Amling, Christopher L; Coakley, Fergus V

2018-04-25

To evaluate the length of contact between dominant tumor foci and the prostatic capsule as a sign of extracapsular extension at endorectal multiparametric MR imaging. We retrospectively identified 101 patients over a three-year interval who underwent endorectal multiparametric prostate MR imaging prior to radical prostatectomy for prostate cancer. Two readers identified the presence of dominant tumor focus (largest lesion with PI-RADS version 2 score of 4 or 5), and measured the length of tumor capsular contact and likelihood of extracapsular extension by standard criteria (1-5 Likert scale). Results were analyzed using histopathological review as reference standard. Extracapsular extension was found at histopathological review in 27 patients. Reader 1 (2) identified dominant tumor in 79 (73) patients, with mean tumor capsular contact length of 18.2 (14.0) mm. The area under the receiver operating characteristic curve for identification of extracapsular extension by tumor capsular contact length was 0.76 for reader 1 and 0.77 for reader 2, with optimal discrimination at values of 18 mm and 21 mm, respectively. In the subset of patients without obvious extracapsular extension by standard criteria (Likert scores 1-3), corresponding values were 0.74 and 0.66 with optimal thresholds of 24 and 21 mm. Length of contact between the dominant tumor focus and the capsule is a moderately useful sign of extracapsular extension at endorectal multiparametric prostate MR imaging, including the subset of patients without obvious extracapsular extension by standard criteria, with optimal discrimination at threshold values of 18 to 24 mm. Copyright © 2018 Elsevier Inc. All rights reserved.

Active Immunization with Pneumolysin versus 23-Valent Polysaccharide Vaccine for Streptococcus pneumoniae Keratitis

PubMed Central

Norcross, Erin W.; Sanders, Melissa E.; Moore, Quincy C.; Taylor, Sidney D.; Tullos, Nathan A.; Caston, Rhonda R.; Dixon, Sherrina N.; Nahm, Moon H.; Burton, Robert L.; Thompson, Hilary; McDaniel, Larry S.

2011-01-01

Purpose. The purpose of this study was to determine whether active immunization against pneumolysin (PLY), or polysaccharide capsule, protects against the corneal damage associated with Streptococcus pneumoniae keratitis. Methods. New Zealand White rabbits were actively immunized with Freund's adjuvant mixed with pneumolysin toxoid (ψPLY), Pneumovax 23 (PPSV23; Merck, Whitehouse Station, NJ), or phosphate-buffered saline (PBS), before corneal infection with 105 colony-forming units (CFU) of S. pneumoniae. Serotype-specific rabbit polyclonal antisera or mock antisera were passively administered to rabbits before either intravenous infection with 1011 CFU S. pneumoniae or corneal infection with 105 CFU of S. pneumoniae. Results. After active immunization, clinical scores of corneas of the rabbits immunized with ψPLY and Freund's adjuvant were significantly lower than scores of the rabbits that were mock immunized with PBS and Freund's adjuvant or with PPSV23 and Freund's adjuvant at 48 hours after infection (P ≤ 0.0010), whereas rabbits immunized with PPSV23 and Freund's adjuvant failed to show differences in clinical scores compared with those in mock-immunized rabbits (P = 1.00) at 24 and 48 hours after infection. Antisera from rabbits actively immunized with PPSV23 and Freund's adjuvant were nonopsonizing. Bacterial loads recovered from infected corneas were higher for the ψPLY- and PPSV23-immunized rabbits after infection with WU2, when compared with the mock-immunized rabbits (P ≤ 0.007). Conversely, after infection with K1443, the ψPLY-immunized rabbits had lower bacterial loads than the control rabbits (P = 0.0008). Quantitation of IgG, IgA, and IgM in the sera of ψPLY-immunized rabbits showed high concentrations of PLY-specific IgG. Furthermore, anti-PLY IgG purified from ψPLY-immunized rabbits neutralized the cytolytic effects of PLY on human corneal epithelial cells. Passive administration of serotype-specific antisera capable of opsonizing and

Synthesis, characterization and evaluation of thiolated tamarind seed polysaccharide as a mucoadhesive polymer.

PubMed

Kaur, Harmanmeet; Yadav, Shikha; Ahuja, Munish; Dilbaghi, Neeraj

2012-11-06

In the present study, thiol-functionalization of tamarind seed polysaccharide was carried out by esterification with thioglycolic acid. Thiol-functionalization was confirmed by SH stretch in Fourier-transformed infra-red spectra at 2586 cm(-1). It was found to possess 104.5 mM of thiol groups per gram. The results of differential scanning calorimetry and X-ray diffraction study indicate increase in crystallinity. Polymer compacts of thiolated tamarind seed polysaccharide required 6.85-fold greater force to detach from the mucin coated membrane than that of tamarind seed polysaccharide. Comparative evaluation of Carbopol-based metronidazole gels containing thiolated tamarind seed polysaccharide with gels containing tamarind seed polysaccharide for mucoadhesive strength using chicken ileum by modified balance method revealed higher mucoadhesion of gels containing thiolated tamarind seed polysaccharide. Further, the gels containing tamarind seed polysaccharide and thiolated tamarind seed polysaccharide released the drug by Fickian-diffusion following the first-order and Higuchi's-square root release kinetics, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

Computer simulation and experimental study of the polysaccharide-polysaccharide interaction in the bacteria Azospirillum brasilense Sp245

NASA Astrophysics Data System (ADS)

Arefeva, Oksana A.; Kuznetsov, Pavel E.; Tolmachev, Sergey A.; Kupadze, Machammad S.; Khlebtsov, Boris N.; Rogacheva, Svetlana M.

2003-09-01

We have studied the conformational properties and molecular dynamics of polysaccharides by using molecular modeling methods. Theoretical and experimental results of polysaccharide-polysaccharide interactions are described.

A polysaccharide of Dendrobium officinale ameliorates H2O2-induced apoptosis in H9c2 cardiomyocytes via PI3K/AKT and MAPK pathways.

PubMed

Zhang, Jing-Yi; Guo, Ying; Si, Jin-Ping; Sun, Xiao-Bo; Sun, Gui-Bo; Liu, Jing-Jing

2017-11-01

Dendrobium officinale is one valuable traditional Chinese medicine, which has skyscraping medicinal value. Polysaccharide is the main active ingredient in D. officinale; its antioxidant activity is a hot research topic nowadays. Oxidative stress plays an important role in the pathological progress of a variety of cardiovascular disease, as one of key factors of cardiomyocyte apoptosis. This research adopts a model of H 2 O 2 induction-H9c2 cardiomyocytes apoptosis, aiming to study the effect of Dendrobium officinale Polysaccharide (DOP-GY) for cardiomyocyte apoptosis caused by oxidative stress and its possible mechanism. Our results showed that pretreatment of DOP-GY (low dose: 6.25μg/mL, medium dose: 12.5μg/mL, high dose: 25μg/mL) followed by a 2h incubation with 200μM H 2 O 2 elevated the survival rate, cutted the LDH leakage, reduced lipid peroxidation damage, improved the activity of the endogenous antioxidant enzymes. In addition, the pretreatment of DOP-GY significantly inhibited the production of ROS, declined of the mitochondrial membrane potential, down-regulated pro-apoptosis protein and up-regulated anti-apoptosis protein. The protective effect was correlated with the PI3K/Akt and MAPK signal pathway. Collectively, these observations suggest that DOY-GY has the potential to exert cardioprotective effects against H 2 O 2 -induced H9c2 cardiomyocyte apoptosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Structural Characteristics of the Novel Polysaccharide FVPA1 from Winter Culinary-Medicinal Mushroom, Flammulina velutipes (Agaricomycetes), Capable of Enhancing Natural Killer Cell Activity against K562 Tumor Cells.

PubMed

Jia, Wei; Feng, Jie; Zhang, Jing-Song; Lin, Chi-Chung; Wang, Wen-Han; Chen, Hong-Ge

2017-01-01

FVPA1, a novel polysaccharide, has been isolated from fruiting bodies of the culinary-medicinal mushroom Flammulina velutipes, a historically popular, widely cultivated and consumed functional food with an attractive taste, beneficial nutraceutical properties such as antitumor and immunomodulatory effects, and a number of essential biological activities. The average molecular weight was estimated to be ~1.8 × 104 Da based on high-performance size exclusion chromatography. Sugar analyses, methylation analyses, and 1H, 13C, and 2-dimensional nuclear magnetic resonance spectroscopy revealed the following structure of the repeating units of the FVPA1 polysaccharide Identification of this structure would conceivably lead to better understanding of the nutraceutical functions of this very important edible fungus. Bioactivity tests in vitro indicated that FVPA1 could significantly enhance natural killer cell activity against K562 tumor cells.

Rational Design and Evaluation of an Artificial Escherichia coli K1 Protein Vaccine Candidate Based on the Structure of OmpA

PubMed Central

Gu, Hao; Liao, Yaling; Zhang, Jin; Wang, Ying; Liu, Zhiyong; Cheng, Ping; Wang, Xingyong; Zou, Quanming; Gu, Jiang

2018-01-01

Escherichia coli (E. coli) K1 causes meningitis and remains an unsolved problem in neonates, despite the application of antibiotics and supportive care. The cross-reactivity of bacterial capsular polysaccharides with human antigens hinders their application as vaccine candidates. Thus, protein antigens could be an alternative strategy for the development of an E. coli K1 vaccine. Outer membrane protein A (OmpA) of E. coli K1 is a potential vaccine candidate because of its predominant contribution to bacterial pathogenesis and sub-cellular localization. However, little progress has been made regarding the use of OmpA for this purpose due to difficulties in OmpA production. In the present study, we first investigated the immunogenicity of the four extracellular loops of OmpA. Using the structure of OmpA, we rationally designed and successfully generated the artificial protein OmpAVac, composed of connected loops from OmpA. Recombinant OmpAVac was successfully produced in E. coli BL21 and behaved as a soluble homogenous monomer in the aqueous phase. Vaccination with OmpAVac induced Th1, Th2, and Th17 immune responses and conferred effective protection in mice. In addition, OmpAVac-specific antibodies were able to mediate opsonophagocytosis and inhibit bacterial invasion, thereby conferring prophylactic protection in E. coli K1-challenged adult mice and neonatal mice. These results suggest that OmpAVac could be a good vaccine candidate for the control of E. coli K1 infection and provide an additional example of structure-based vaccine design. PMID:29876324

Rational Design and Evaluation of an Artificial Escherichia coli K1 Protein Vaccine Candidate Based on the Structure of OmpA.

PubMed

Gu, Hao; Liao, Yaling; Zhang, Jin; Wang, Ying; Liu, Zhiyong; Cheng, Ping; Wang, Xingyong; Zou, Quanming; Gu, Jiang

2018-01-01

Escherichia coli ( E. coli ) K1 causes meningitis and remains an unsolved problem in neonates, despite the application of antibiotics and supportive care. The cross-reactivity of bacterial capsular polysaccharides with human antigens hinders their application as vaccine candidates. Thus, protein antigens could be an alternative strategy for the development of an E. coli K1 vaccine. Outer membrane protein A (OmpA) of E. coli K1 is a potential vaccine candidate because of its predominant contribution to bacterial pathogenesis and sub-cellular localization. However, little progress has been made regarding the use of OmpA for this purpose due to difficulties in OmpA production. In the present study, we first investigated the immunogenicity of the four extracellular loops of OmpA. Using the structure of OmpA, we rationally designed and successfully generated the artificial protein OmpAVac, composed of connected loops from OmpA. Recombinant OmpAVac was successfully produced in E. coli BL21 and behaved as a soluble homogenous monomer in the aqueous phase. Vaccination with OmpAVac induced Th1, Th2, and Th17 immune responses and conferred effective protection in mice. In addition, OmpAVac-specific antibodies were able to mediate opsonophagocytosis and inhibit bacterial invasion, thereby conferring prophylactic protection in E. coli K1-challenged adult mice and neonatal mice. These results suggest that OmpAVac could be a good vaccine candidate for the control of E. coli K1 infection and provide an additional example of structure-based vaccine design.

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

Molecular mechanism of lytic polysaccharide monooxygenases.

PubMed

Hedegård, Erik Donovan; Ryde, Ulf

2018-04-21

The lytic polysaccharide monooxygenases (LPMOs) are copper metalloenzymes that can enhance polysaccharide depolymerization through an oxidative mechanism and hence boost generation of biofuel from e.g. cellulose. By employing density functional theory in a combination of quantum mechanics and molecular mechanics (QM/MM), we report a complete description of the molecular mechanism of LPMOs. The QM/MM scheme allows us to describe all reaction steps with a detailed protein environment and we show that this is necessary. Several active species capable of abstracting a hydrogen from the substrate have been proposed previously and starting from recent crystallographic work on a substrate-LPMO complex, we investigate previously suggested paths as well as new ones. We describe the generation of the reactive intermediates, the abstraction of a hydrogen atom from the polysaccharide substrate, as well as the final recombination step in which OH is transferred back to the substrate. We show that a superoxo [CuO 2 ] + complex can be protonated by a nearby histidine residue (suggested by recent mutagenesis studies and crystallographic work) and, provided an electron source is available, leads to formation of an oxyl-complex after cleavage of the O-O bond and dissociation of water. The oxyl complex either reacts with the substrate or is further protonated to a hydroxyl complex. Both the oxyl and hydroxyl complexes are also readily generated from a reaction with H 2 O 2 , which was recently suggested to be the true co-substrate, rather than O 2 . The C-H abstraction by the oxyl and hydroxy complexes is overall favorable with activation barriers of 69 and 94 kJ mol -1 , compared to the much higher barrier (156 kJ mol -1 ) obtained for the copper-superoxo species. We obtain good structural agreement for intermediates for which structural data are available and the estimated reaction energies agree with experimental rate constants. Thus, our suggested mechanism is the most complete

Structural characterization of an immunostimulating polysaccharide from the stems of a new medicinal Dendrobium species: Dendrobium Taiseed Tosnobile.

PubMed

Yang, Li-Chan; Hsieh, Chang-Chi; Wen, Chi-Luan; Chiu, Chun-Hui; Lin, Wen-Chuan

2017-10-01

Dendrobium Taiseed Tosnobile, a new Dendrobium species developed by crossbreeding Dendrobium tosaense and Dendrobium nobile, exhibits the characteristics of high mass production and high polysaccharide content. This study investigated the structural characterization and immunostimulating effects of a polysaccharide isolated from D. Taiseed Tosnobile (DTTPS). DTTPS was fractioned using a DEAE-650M column to obtain the major neutral polysaccharide (DTTPS-N). The structural characteristics of DTTPS-N were investigated through high-performance anion exchange chromatography, high-performance size exclusion chromatography, gas chromatography-mass spectrometry, and nuclear magnetic resonance spectroscopy. In the immunostimulating experiment, BALB/c mice were administered DTTPS (100 and 300mg/kg) daily for 3 weeks. The results revealed that DTTPS-N comprised arabinose, galactose, glucose, mannose, and xylose at a ratio of 1:1.5:3.0:29.9:1.3. DTTPS-N comprised (1→3; 1→4)-Man as the backbone, and its average molecular weight was 281kDa. Pharmacological experiments demonstrated that DTTPS substantially increased the population of splenic natural killer (NK) cells, NK cytotoxicity, macrophage phagocytosis, and cytokine induction. This is the first study to demonstrate the structural characteristics and immunopharmacological effects of an active polysaccharide derived from D. Taiseed Tosnobile. Copyright © 2017 Elsevier B.V. All rights reserved.

Structural, functional and pH sensitive release characteristics of water-soluble polysaccharide from the seeds of Albizia lebbeck L.

PubMed

Kumar Varma, Chekuri Ashok; Jayaram Kumar, K

2017-11-01

Plant polysaccharides, generally regarded as safe (GRAS), are gaining importance as excipients in drug delivery. Therefore, the current paper presents the studies on structural, functional and drug release study of water soluble polysaccharide (ALPS) from seeds of Albizia lebbeck L. High swelling, water holding capacity, foam stability and lower moisture content suggests its use as additive in food preparations. The apparent molecular weight of polysaccharide was found to be 1.98×10 2 kDa. Monosaccharide composition analysis indicated that ALPS consists of mannose (4.06%), rhamnose (22.79%), glucose (38.9%), galactose (17.84%) and xylose (16.42%). Micromeritic properties revealed that the polysaccharide possess potential for pharmaceutical applications. From the surface charge analysis, ALPS was found to be non-ionic polysaccharide. Morphological study reveals the polysaccharide with irregular particle shape and rough surface. Fourier transformed infrared spectroscopy (FTIR) study confirms the carbohydrate nature of polysaccharide. From the thermogravimetric analysis (TGA) data, the second mass loss (243-340°C) attributed to polysaccharide degradation. The drug release profile reveals the use of polysaccharide for the preparation of pH sensitive pharmaceutical dosage forms. Copyright © 2017 Elsevier Ltd. All rights reserved.

Description and Nomenclature of Neisseria meningitidis Capsule Locus

PubMed Central

Claus, Heike; Jiang, Ying; Bennett, Julia S.; Bratcher, Holly B.; Jolley, Keith A.; Corton, Craig; Care, Rory; Poolman, Jan T.; Zollinger, Wendell D.; Frasch, Carl E.; Stephens, David S.; Feavers, Ian; Frosch, Matthias; Parkhill, Julian; Vogel, Ulrich; Quail, Michael A.; Bentley, Stephen D.; Maiden, Martin C.J.

2013-01-01

Pathogenic Neisseria meningitidis isolates contain a polysaccharide capsule that is the main virulence determinant for this bacterium. Thirteen capsular polysaccharides have been described, and nuclear magnetic resonance spectroscopy has enabled determination of the structure of capsular polysaccharides responsible for serogroup specificity. Molecular mechanisms involved in N. meningitidis capsule biosynthesis have also been identified, and genes involved in this process and in cell surface translocation are clustered at a single chromosomal locus termed cps. The use of multiple names for some of the genes involved in capsule synthesis, combined with the need for rapid diagnosis of serogroups commonly associated with invasive meningococcal disease, prompted a requirement for a consistent approach to the nomenclature of capsule genes. In this report, a comprehensive description of all N. meningitidis serogroups is provided, along with a proposed nomenclature, which was presented at the 2012 XVIIIth International Pathogenic Neisseria Conference. PMID:23628376

[Conjugated vaccines].

PubMed

Fritzell, Bernard

2005-01-01

Encapsulated bacterial pathogens (e.g. Haemophilus influenzae type b [Hib], Neisseria meningitidis, or Streptococcus pneumoniae) target infants and young children who have lost any protective anti-capsular antibodies supplied maternally and whose immune systems are ineffective against T-independent antigens such as the polysaccharides of the capsule. The polysaccharide-protein conjugate vaccines overcome this limitation by converting the polysaccharide to a T-dependent antigen, which allows a vaccinated infant to mount a protective immune response. Where conjugated vaccines have been introduced into paediatric vaccination schedules, the incidence of invasive diseases caused by Hib, the group C meningococcus, or the pneumococcus has plummeted by at least 80%, a major public health success. Furthermore, surveillance has demonstrated that the conjugate vaccines provide 'herd protection' through their beneficial impact on nasopharyngeal colonisation among vaccinated children. Promising future approaches include enhancement of the number of capsular serogroups targeted by the meningococcal or pneumococcal conjugate vaccines.

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

no exception despite their poor overall metabolic capacity. We showed here that M. agalactiae secretes a capsular β-(1→6)-glucopyranose thanks to a specific glycosyltransferase with synthase activity. This secretion is governed by high-frequency ON/OFF phase variation that might be crucial in mycoplasma host dissemination, as cell-attached β-(1→6)-glucopyranose increases serum-killing susceptibility. Our results provide functional genetic data about mycoplasmal glycosyltransferases with dual functions, i.e., assembly and export of the sugar polymers across the cell membrane. Furthermore, we demonstrated that nonprotein epitopes can be subjected to surface antigenic variation in mycoplasmas. Finally, the present report contributes to unravel the role of secreted polysaccharides in the virulence and pathogenicity of these peculiar bacteria. PMID:27037120

The effect of nonablative laser energy on joint capsular properties. An in vitro histologic and biochemical study using a rabbit model

NASA Technical Reports Server (NTRS)

Hayashi, K.; Thabit, G. 3rd; Vailas, A. C.; Bogdanske, J. J.; Cooley, A. J.; Markel, M. D.

1996-01-01

The purpose of this study was to evaluate the effect of laser energy at nonablative levels on joint capsular histologic and biochemical properties in an in vitro rabbit model. The medial and lateral portions of the femoropatellar joint capsule from both stifles of 12 mature New Zealand White rabbits were used. Specimens were divided into three treatment groups (5 watts, 10 watts, and 15 watt) and one control group using a randomized block design. Specimens were placed in a 37 degrees bath of lactated Ringer's solution and laser energy was applied using a holmium:yttrium-aluminum-garnet laser in four transverse passes across the tissue at a velocity of 2 mm/sec with the handpiece set 1.5 mm from the synovial surface. Histologic analysis revealed thermal alteration of collagen (fusion) and fibroblasts (pyknosis) at all energy densities, with higher laser energy causing significantly greater morphologic changes over a larger area (P < 0.05). Application of laser energy did not significantly alter the biochemical parameters evaluated, including type I collagen content and nonreducible crosslinks (P > 0.05). This study demonstrated that nonablative laser energy caused significant thermal damage to the joint capsular tissue in an energy-dependent fashion, but type I collagen content and nonreducible crosslinks (P > 0.05). This study demonstrated that nonablative laser energy caused significant thermal damage to the joint capsular tissue in an energy-dependent fashion, but type I Collagen content and nonreducible corsslinks were not significantly altered.

Purification, characterization and immunomodulatory activity of polysaccharides from stem lettuce.

PubMed

Nie, Chenzhipeng; Zhu, Peilei; Ma, Shuping; Wang, Mingchun; Hu, Youdong

2018-05-15

Stem lettuce has a long history of cultivation in China and possesses high nutritional and medicinal value. In our previous studies, extraction optimization, characterization, and bioactivities of stem lettuce polysaccharides (SLP) were investigated. In this study, SLP were further separated into two purified polysaccharides, SLP-1 and SLP-2, by anion exchange chromatography followed by size exclusion chromatography. SLP-1, with a molecular weight of 90 KDa, was mainly composed of galacturonic acid, galactose and arabinose in a molar ratio of 17.6:41.7:33.9. SLP-2, with a molecular weight of 44 KDa, was mainly composed of mannose, galacturonic acid, galactose and arabinose in a molar ratio of 11.5:69.5:9.3:8.2. In addition, both purified polysaccharides contain sulphate radicals, have triple helical structures and can promote macrophage proliferation without cytotoxicity. SLP-2 was better able to stimulate phagocytic and nitric oxide production than SLP-1. The results suggest that polysaccharides from stem lettuce could be explored as immunomodulatory agents in the field of pharmaceuticals and functional foods. Copyright © 2018 Elsevier Ltd. All rights reserved.

THE ANTIBODY-FORMATION BY POLYSACCHARIDS

PubMed Central

Nishimura, Shoji

1929-01-01

1. By complement fixation tests, it has been clearly demonstrated that the sera of rabbits immunized with inulin, soluble starch and dextrine contain specific antibodies. 2. All these immune sera gave a negative precipitation reaction. 3. The kind of dextrine which has a construction very near to starch has an antigenic property, but those in a state of further decomposition do not give rise to antibodies. 4. All the three kinds of polysaccharids have power to produce antibodies without any vehicle. Dextrine is the only one of the three that gives rise to immune bodies more readily when pig serum is added to it. 5. Regarded as antigens, inulin stood first and soluble starch and dextrine next in order. 6. All three kinds of polysaccharids that were employed gave a negative protein color reaction. All of them, however, contained nitrogen. It has been proved that the large portion of the nitrogen contained in the soluble starch is derived from its protein contents. 7. It is suggested that in the production of immune bodies by these three kinds of polysaccharids, proteins might play the part of the vehicle. This is, however, still to be determined. PMID:19869634

THE ANTIBODY-FORMATION BY POLYSACCHARIDS.

PubMed

Nishimura, S

1929-09-30

1. By complement fixation tests, it has been clearly demonstrated that the sera of rabbits immunized with inulin, soluble starch and dextrine contain specific antibodies. 2. All these immune sera gave a negative precipitation reaction. 3. The kind of dextrine which has a construction very near to starch has an antigenic property, but those in a state of further decomposition do not give rise to antibodies. 4. All the three kinds of polysaccharids have power to produce antibodies without any vehicle. Dextrine is the only one of the three that gives rise to immune bodies more readily when pig serum is added to it. 5. Regarded as antigens, inulin stood first and soluble starch and dextrine next in order. 6. All three kinds of polysaccharids that were employed gave a negative protein color reaction. All of them, however, contained nitrogen. It has been proved that the large portion of the nitrogen contained in the soluble starch is derived from its protein contents. 7. It is suggested that in the production of immune bodies by these three kinds of polysaccharids, proteins might play the part of the vehicle. This is, however, still to be determined.

Characterization of Escherichia coli K1 colominic acid-specific murine antibodies that are cross-protective against Neisseria meningitidis groups B, C, and Y.

PubMed

Park, In Ho; Lin, Jisheng; Choi, Ji Eun; Shin, Jeon-Soo

2014-06-01

The capsular polysaccharide (PS) of Neisseria meningitidis serogroup B (NMGB) is α(2-8)-linked N-acetylneuraminic acid (Neu5Ac), which is almost identical to the O-acetylated colominic acid (CA) of Escherichia coli K1 Although E. coli K1 has long been known to elicit cross-protective antibodies against NMGB, limited information on these highly cross-reactive antibodies is available. In the present study, six new monoclonal antibodies (mAbs) specific to both E. coli K1 CA and NMGB PS were produced by immunizing Balb/c mice with E. coli K1, and their serological and molecular properties were characterized, together with 12 previously reported hybridoma mAbs. Among the bactericidal mAbs against NMGB, both HmenB5 and HmenB18, which are genetically identical though of different mouse origins, were able to kill serogroup C and Y meningococci. Based on SPR sensograms, the binding affinity of HmenB18 for PS was suggested to be associated with at least two different binding forces: the polyanionicity of Neu5Ac and an interaction with the O-acetyl groups of Neu5Ac. Molecular analysis showed that similar to most mAbs presenting a few restricted V region germline genes, the V region genes of HmenB18 were 979% and 986% identical to the closest IGHV1-1401 and IGLV15-10301 germline gene alleles, respectively, and V-D-J editing in this mAb generated an unusually long VH-CDR3 sequence (17 amino acid residues), containing one basic arginine, two hydrophobic isoleucine residues and a 'YAMDY' motif. Models of the mAb combining sites demonstrate that most of the mAbs exhibited a wide, shallow groove with a high overall positive charge, as seen in mAb735, which is specific for a polyanionic helical epitope. In contrast, the combining site of HmenB18 was shown to be wide but to present a relatively weak positive charge, consistent with the extensive recognition by HmenB18 of the various structural epitopes formed with the Neu5Ac residue and its O-acetylation. Copyright © 2014 Elsevier

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. Copyright © 2015 Elsevier B.V. All rights reserved.

Properties of the polysaccharide and mucopeptide components of the cell wall of Lactobacillus casei

PubMed Central

Hall, Elizabeth A.; Knox, K. W.

1965-01-01

1. The polysaccharide and mucopeptide components of the cell wall of Lactobacillus casei have been separated by mild conditions of acid hydrolysis. 2. Removal of the polysaccharide renders the mucopeptide susceptible to lysozyme. 3. The mucopeptide and polysaccharide components have been analysed and the results compared with those obtained previously. 4. The polysaccharides responsible for group specificity have a terminal reducing N-acetylgalactosamine residue substituted on C(3) by the adjacent sugar; estimation of this component gave an indication of the molecular weight of the polysaccharides. 5. Evidence has been obtained for the presence of rhamnosyl-(1→3)-N-acetylgalactosamine among the products of acid hydrolysis of the group B polysaccharide. ImagesFig. 2. PMID:5837778

Quantitation of antibodies to Haemophilus influenzae type b in humans by enzyme-linked immunosorbent assay.

PubMed Central

Dahlberg, T

1981-01-01

The enzyme-linked immunosorbent assay was adapted to detect serum immunoglobulin G, immunoglobulin M, immunoglobulin A, and secretory immunoglobulin A antibodies to Haemophilus influenzae type b capsular polysaccharide in humans. I studied serum samples from 92 healthy children of various ages, 50 healthy adults, 24 patients with various H. influenzae type b infections, and 16 patients with clinical signs of epiglottis and cellulitis suspected to be caused by H. influenzae type b. The mean antibody titers of the sera from healthy children increased with age and reached adult levels in children more than 6 years old. A significant antibody response to capsular polysaccharide was observed in serum samples from the majority of patients with infections due to H. influenzae type b and in 4 of 16 patients with clinical signs of epiglottis and cellulitis. In addition to the enzyme-linked immunosorbent assay, the antibody responses of patients were tested by a bactericidal assay. When the two methods were compared, there was no evident correlation (r, about 0.22). The enzyme-linked immunosorbent assay was further adapted to test secretory immunoglobulin A antibodies specific to capsular polysaccharide in nasopharynx secretions and in milk samples from lactating women. Antibodies were detected in 12 of 24 secretions and 9 of 11 milk samples. PMID:7019237

Pneumococcal Capsules and Their Types: Past, Present, and Future.

PubMed

Geno, K Aaron; Gilbert, Gwendolyn L; Song, Joon Young; Skovsted, Ian C; Klugman, Keith P; Jones, Christopher; Konradsen, Helle B; Nahm, Moon H

2015-07-01

Streptococcus pneumoniae (the pneumococcus) is an important human pathogen. Its virulence is largely due to its polysaccharide capsule, which shields it from the host immune system, and because of this, the capsule has been extensively studied. Studies of the capsule led to the identification of DNA as the genetic material, identification of many different capsular serotypes, and identification of the serotype-specific nature of protection by adaptive immunity. Recent studies have led to the determination of capsular polysaccharide structures for many serotypes using advanced analytical technologies, complete elucidation of genetic basis for the capsular types, and the development of highly effective pneumococcal conjugate vaccines. Conjugate vaccine use has altered the serotype distribution by either serotype replacement or switching, and this has increased the need to serotype pneumococci. Due to great advances in molecular technologies and our understanding of the pneumococcal genome, molecular approaches have become powerful tools to predict pneumococcal serotypes. In addition, more-precise and -efficient serotyping methods that directly detect polysaccharide structures are emerging. These improvements in our capabilities will greatly enhance future investigations of pneumococcal epidemiology and diseases and the biology of colonization and innate immunity to pneumococcal capsules. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Use of the chop hook to stabilize the capsular bag in patients with crystalline lens dislocations and cataracts.

PubMed

Zeng, Yanfeng; Fan, Licheng; Lu, Peirong

2017-04-01

Objective To observe the treatment effects of chop hook-assisted phacoemulsification surgery in patients with crystalline lens dislocation. Methods Thirty-seven eyes with cataracts and crystalline lens dislocations underwent cataract surgery. An L-shaped chop hook was introduced into the anterior chamber, and the tip was pushed or pulled to the centre of the anterior capsular edge of the zonular dialysis during the cataract operation. Postoperative follow-up was conducted for ≥ 1 month. Results All patients' postoperative visual abilities improved except one patient with glaucoma. One patient who underwent -5D intraocular lens implantation exhibited vision of 1/50. Visual acuity was less than 6/20 in 6 eyes, 6/20 to 10/20 in 7 eyes, and greater than 10/20 in 22 eyes. Conclusions L-shaped chop hooks can be used to push or pull the anterior capsular edge of the zonular dialysis for protection and avoidance of further zonular damage. This strategy provides satisfactory effects and reduces use of additional instruments.

Polysaccharide-Based Micelles for Drug Delivery

PubMed Central

Zhang, Nan; Wardwell, Patricia R.; Bader, Rebecca A.

2013-01-01

Delivery of hydrophobic molecules and proteins has been an issue due to poor bioavailability following administration. Thus, micelle carrier systems are being investigated to improve drug solubility and stability. Due to problems with toxicity and immunogenicity, natural polysaccharides are being explored as substitutes for synthetic polymers in the development of new micelle systems. By grafting hydrophobic moieties to the polysaccharide backbone, self-assembled micelles can be readily formed in aqueous solution. Many polysaccharides also possess inherent bioactivity that can facilitate mucoadhesion, enhanced targeting of specific tissues, and a reduction in the inflammatory response. Furthermore, the hydrophilic nature of some polysaccharides can be exploited to enhance circulatory stability. This review will highlight the advantages of polysaccharide use in the development of drug delivery systems and will provide an overview of the polysaccharide-based micelles that have been developed to date. PMID:24300453

Purification, structural characterization and anticancer activity of the novel polysaccharides from Rhynchosia minima root.

PubMed

Jia, Xuejing; Zhang, Chao; Qiu, Jianfeng; Wang, Lili; Bao, Jiaolin; Wang, Kai; Zhang, Yulin; Chen, Meiwan; Wan, Jianbo; Su, Huanxing; Han, Jianping; He, Chengwei

2015-11-05

Three novel acidic polysaccharides termed PRM1, PRM3 and PRM5 were purified from Rhynchosia minima root using DEAE-52 cellulose and sephadex G-150 column chromatography. Their structures were characterized by ultraviolet (UV) and Fourier transform infrared (FTIR) spectrometry, gel permeation chromatography (GPC), gas chromatography-mass spectrometry (GC-MS), and differential scanning colorimeter (DSC) analysis. The uronic acid contents of PRM1, PRM3 and PRM5 were 30.7%, 12.7% and 47.7%, respectively. PRM1 (143.2 kDa), PRM3 (105.3 kDa) and PRM5 (162.1 kDa) were heteropolysaccharides because they were composed of arabinose, mannose, glucose and galactose. Their enthalpy values were 201.0, 111.0 and 206.8 J/g, respectively. PRM3 and PRM1 exhibited strong in vitro anticancer activity against lung cancer A549 and liver cancer HepG2 cells in a dose-dependent manner. These findings suggested that PRM1 and PRM3 could be potentially developed as natural anticancer agents. Copyright © 2015 Elsevier Ltd. All rights reserved.

The risk of capsular breakage from phacoemulsification needle contact with the lens capsule: a laboratory study.

PubMed

Meyer, Jay J; Kuo, Annie F; Olson, Randall J

2010-06-01

To determine capsular breakage risk from contact by phacoemulsification needles by machine and tip type. Experimental laboratory investigation. Infiniti (Alcon, Inc.) with Intrepid cartridges and Signature (Abbott Medical Optics, Inc.) phacoemulsification machines were tested using 19- and 20-gauge sharp and rounded tips. Actual and unoccluded flow vacuum were determined at 550 mm Hg, bottle height of 75 cm, and machine-indicated flow rate of 60 mL/minute. Breakage from brief tip contact with a capsular surrogate and human cadaveric lenses was calculated. Nineteen-gauge tips had more flow and less unoccluded flow vacuum than 20-gauge tips for both machines, with highest unoccluded flow vacuum in the Infiniti. The 19-gauge sharp tip was more likely than the 20-gauge sharp tip to cause surrogate breakage for Signature with micropulse and Ellips (Abbott Medical Optics, Inc.) ultrasound at 100% power. For Infiniti using OZil (Alcon, Inc.) ultrasound, 20-gauge sharp tips were more likely than 19-gauge sharp tips to break the membrane. For cadaveric lenses, using rounded 20-gauge tips at 100% power, breakage rates were micropulse (2.3%), Ellips (2.3%), OZil (5.3%). Breakage rates for sharp 20-gauge Ellips tips were higher than for rounded tips. Factors influencing capsular breakage may include active vacuum at the tip, flow rate, needle gauge, and sharpness. Nineteen-gauge sharp tips were more likely than 20-gauge tips to cause breakage in lower vacuum methods. For higher-vacuum methods, breakage is more likely with 20-gauge than with 19-gauge tips. Rounded-edge tips are less likely than sharp-edged tips to cause breakage. Copyright 2010 Elsevier Inc. All rights reserved.

Discovery and characterization of sialic acid O-acetylation in group B Streptococcus.

PubMed

Lewis, Amanda L; Nizet, Victor; Varki, Ajit

2004-07-27

Group B Streptococcus (GBS) is the leading cause of human neonatal sepsis and meningitis. The GBS capsular polysaccharide is a major virulence factor and the active principle of vaccines in phase II trials. All GBS capsules have a terminal alpha 2-3-linked sialic acid [N-acetylneuraminic acid (Neu5Ac)], which interferes with complement-mediated killing. We show here that some of the Neu5Ac residues of the GBS type III capsule are O-acetylated at carbon position 7, 8, or 9, a major modification evidently missed in previous studies. Data are consistent with initial O-acetylation at position 7, and subsequent migration of the O-acetyl ester at positions 8 and 9. O-acetylation was also present on several other GBS serotypes (Ia, Ib, II, V, and VI). Deletion of the CMP-Neu5Ac synthase gene neuA by precise, in-frame allelic replacement gave intracellular accumulation of O-acetylated Neu5Ac, whereas overexpression markedly decreased O-acetylation. Given the known GBS Neu5Ac biosynthesis pathway, these data indicate that O-acetylation occurs on free Neu5Ac, competing with the CMP-Neu5Ac synthase. O-acetylation often generates immunogenic epitopes on bacterial capsular polysaccharides and can modulate human alternate pathway complement activation. Thus, our discovery has important implications for GBS pathogenicity, immunogenicity, and vaccine design.

Polysaccharides purified from wild Cordyceps activate FGF2/FGFR1c signaling

NASA Astrophysics Data System (ADS)

Zeng, Yangyang; Han, Zhangrun; Yu, Guangli; Hao, Jiejie; Zhang, Lijuan

2015-02-01

Land animals as well as all organisms in ocean synthesize sulfated polysaccharides. Fungi split from animals about 1.5 billion years ago. As fungi make the evolutionary journey from ocean to land, the biggest changes in their living environment may be a sharp decrease in salt concentration. It is established that sulfated polysaccharides interact with hundreds of signaling molecules and facilitate many signaling transduction pathways, including fibroblast growth factor (FGF) and FGF receptor signaling pathway. The disappearance of sulfated polysaccharides in fungi and plants on land might indicate that polysaccharides without sulfation might be sufficient in facilitating protein ligand/receptor interactions in low salinity land. Recently, it was reported that plants on land start to synthesize sulfated polysaccharides in high salt environment, suggesting that fungi might be able to do the same when exposed in such environment. Interestingly, Cordyceps, a fungus habituating inside caterpillar body, is the most valued traditional Chinese Medicine. One of the important pharmaceutical active ingredients in Cordyceps is polysaccharides. Therefore, we hypothesize that the salty environment inside caterpillar body might allow the fungi to synthesize sulfated polysaccharides. To test the hypothesis, we isolated polysaccharides from both lava and sporophore of wild Cordyceps and also from Cordyceps militaris cultured without or with added salts. We then measured the polysaccharide activity using a FGF2/FGFR1c signaling-dependent BaF3 cell proliferation assay and found that polysaccharides isolated from wild Cordyceps activated FGF2/FGFR signaling, indicating that the polysaccharides synthesized by wild Cordyceps are indeed different from those by the cultured mycelium.

Open inferior capsular shift for multidirectional shoulder instability in adolescents with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome.

PubMed

Vavken, Patrick; Tepolt, Frances A; Kocher, Mininder S

2016-06-01

The objective of this study was to assess the outcome of open inferior capsular shift for multidirectional shoulder instability in patients with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome. Data were obtained for 18 open inferior capsular shift surgeries in 15 adolescent patients with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome with a mean follow-up of 7.5 years. End points were subjective clinical outcome (pain, stability, satisfaction, return to sport), objective clinical outcome (recurrence, complications), and functional outcome scores (American Shoulder and Elbow Surgeons, 11-item version of the Disabilities of Arm, Shoulder and Hand). Thirteen patients (87%) reported improved pain and stability and were satisfied with the procedure. Nine patients (64%) were able to return to sports. One patient (7%) was dissatisfied with continuous pain and recurrent instability and considered a surgical failure. Seven patients (47%) reported no further episodes of instability. The mean American Shoulder and Elbow Surgeons score at a mean of 7.5 years of follow-up was 88 ± 10 points, and the mean score for the 11-item version of the Disabilities of Arm, Shoulder and Hand was 14 ± 14 points. The management of multidirectional shoulder instability in adolescent patients with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome is challenging. Open inferior capsular shift results in improvement in subjective and objective shoulder function and stability in adolescent patients with ligamentous hyperlaxity or Ehlers-Danlos who have failed nonoperative treatment. We found no effect of the recalled number of prior dislocations, laterality, and type of hyperlaxity on subjective and objective clinical outcomes. Level IV; Case Series; Treatment Study. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Predictors for perioperative blood transfusion in elderly patients with extra capsular hip fractures treated with cephalo-medullary nailing.

PubMed

Fazal, M Ali; Bagley, Caroline; Garg, Parag

2018-02-01

The aim of our study was to determine predictive factors and requirement for perioperative blood transfusion in elderly patients with extra capsular hip fractures treated with cephalo-medullary device. Seventy-nine patients with extra capsular hip fractures treated with cephalo-medullary nailing were included in the study. Age, sex, ASA grade, timing of surgery, preoperative and postoperative haemoglobin, length of hospital stay, fracture type, number of units transfused and 30-day mortality were recorded. The mean age was 82.3 years. Forty-seven patients underwent a short nail and 32 patients a long nail; 53.4% patients required blood transfusion postoperatively. Transfusion was required in 71.8% of the long nails (p < 0.05), 65.8% patients above the age of 80 (p < 0.05), 100% of the patients with hemoglobin below 90 g/L and 20 patients with a ASA grade of 3 (p < 0.05). 78.5% patients with A2 fracture and 75% of A3 fractures needed blood transfusion (p > 0.05). Length of hospital stay in non-transfusion group was 13 days and in transfusion group was 19 days (p < 0.05). 55.1% operated within 36 h and 47.6% operated after 36 h of admission needed transfusion (p > 0.05). Thirty-day mortality in patients needing blood transfusion was 5% and in non-transfusion group was 3.7% (p > 0.05). Patient age, ASA grade, preoperative haemoglobin and length of nail are reliable predictors for perioperative blood transfusion in extra capsular hip fractures in elderly patients treated with cephalo-medullary nailing and reinforce a selective transfusion policy. Copyright © 2017 Daping Hospital and the Research Institute of Surgery of the Third Military Medical University. Production and hosting by Elsevier B.V. All rights reserved.

Quorum sensing molecule-farnesol increased the production and biological activities of extracellular polysaccharide from Trametes versicolor.

PubMed

Wang, Ke-Feng; Sui, Kun-Yan; Guo, Chen; Liu, Chun-Zhao

2017-11-01

A novel strategy of exposing 2-day-old mycelia cultures to 0.8mM farnesol was developed to stimulate extracellular polysaccharide (EPS) production in Trametes versicolor submerged cultures. Farnesol, a quorum sensing molecule in fungi, could significantly increase EPS production by promoting polysaccharide biosynthesis and regulating mycelial morphology. EPS yield reached a maximum of 2.56g/L that was 2.7-fold greater than that of control cultures. Farnesol made T. versicolor develop into fluffy, loose and multi-hyphae morphology, which facilitated the excretion of intracellular polysaccharide into culture medium. Moreover, EPS from farnesol-induced cultures (EPS-F) with higher carbohydrate and uronic acid contents mainly contained high molecular weight polysaccharide (134kDa, 85%), and comprised glucose, mannose and galactose in a molar ratio of 34.2:2.1:1.0. These physicochemical properties led to stronger antioxidant and antitumor activities of EPS-F. This is the first report that farnesol can significantly improve the production of polysaccharide with higher biological activities. It provides a novel strategy to enhance the production and bioactivity of mushroom polysaccharide using microbial quorum sensing molecules. Copyright © 2017 Elsevier B.V. All rights reserved.

Extracellular proteins, polysaccharides and enzymes impact on sludge aerobic digestion after ultrasonic pretreatment.

PubMed

Yu, Guang-Hui; He, Pin-Jing; Shao, Li-Ming; Zhu, Yi-Shu

2008-04-01

Ultrasonic pretreatment of excess sludge can improve its aerobic digestibility, leading to enhanced sludge reduction. In order to understand the mechanisms of this improvement, sludge flocs were divided into four layers, i.e. (1) slime, (2) loosely bound extracellular polymeric substances (LB-EPS), (3) tightly bound EPS (TB-EPS) and (4) pellet. Extracellular proteins, polysaccharides and five types of hydrolytic enzymes (protease, alpha-amylase, alpha-glucosidase, alkaline-phosphatase and acid-phosphatase) from sludge flocs were investigated to determine their influence on sludge aerobic digestion after ultrasonic pretreatment. Results suggested that most of the extracellular enzymes (except alpha-amylase) were present in pellet and TB-EPS layers, with minor quantities detected in LB-EPS and slime layers, and almost none detected in bulk solution. As for alpha-amylase in sludge flocs, most of it (52.6%) was also mainly bound with pellet; however, the rest of it was dispersed nearly uniformly throughout the sludge flocs. Ultrasonic pretreatment enhances enzymatic activities and promotes the shifts of extracellular proteins, polysaccharides and enzymes from inner layers of sludge flocs, i.e., pellet and TB-EPS, to outer layers, i.e., slime, to increase the contact and interaction among extracellular proteins, polysaccharides and enzymes that were originally embedded in the sludge flocs, resulting in improved efficiency in aerobic digestion. The optimum ultrasonic pretreatment conditions had a lasting time of 10min and density of 3 kWL(-1) at the frequency of 20 kHz. With the optimum ultrasonic pretreatment, the sludge reduction for TSS in aerobic digestion was 42.7% in which the part of 11.8% was removed by the ultrasonic pretreatment, compared with 20.9% for control, after an aerobic digestion time of 10.5d.

Comparison of Capsular Genes of Streptococcus pneumoniae Serotype 6A, 6B, 6C, and 6D Isolates▿

PubMed Central

Song, Jae-Hoon; Baek, Jin Yang; Ko, Kwan Soo

2011-01-01

Recently, Streptococcus pneumoniae serotypes 6C and 6D have been identified. It is thought that they emerged by the replacement of wciNβ in the capsular loci of serotypes 6A and 6B, respectively. However, their evolution has not been unveiled yet. To investigate the evolution of four serotypes of S. pneumoniae serogroup 6, four genes of the capsular polysaccharide synthesis (cps) locus, wchA, wciN, wciO, and wciP, of isolates of S. pneumoniae serotypes 6A, 6B, 6C, and 6D were sequenced. Multilocus sequence typing (MLST) was performed to investigate their genetic backgrounds. The wchA gene of serotype 6C and 6D isolates was distinct from that of serotype 6A and 6B isolates, which may suggest cotransfer of wchA with wciNβ. Otherwise, serotypes 6C and 6D displayed different genetic backgrounds from serotypes 6A and 6B, which was suggested by MLST analysis. In addition, serotype 6C isolates showed distinct wciP polymorphisms from other serotypes, which also indicated that serotype 6C had not recently originated from serotype 6A. Although serotype 6D shared the same amino acid polymorphisms of wciO with serotype 6B, wciP of serotype 6D differed from that of serotype 6B. The data indicate the implausibility of the scenario of a recent emergence of the cps locus of serotype 6D by genetic recombination between serotypes 6B and 6C. In addition, five serotype 6A and 6B isolates (6X group) displayed cps loci distinct from those of other isolates. The cps locus homogeneity and similar sequence types in MLST analysis suggest that most of the 6X group of isolates originated from the same ancestor and that the entire cps locus might have recently been transferred from an unknown origin. Serotype 6B isolates showed two or more cps locus subtypes, indicating a recombination-mediated mosaic structure of the cps locus of serotype 6B. The collective data favor the emergence of cps loci of serotypes 6A, 6B, 6C, and 6D by complicated recombination. PMID:21411593

Vaccine potential of poly-1-6 beta-D-N-succinylglucosamine, an immunoprotective surface polysaccharide of Staphylococcus aureus and Staphylococcus epidermidis.

PubMed

Mckenney, D; Pouliot, K; Wang, Y; Murthy, V; Ulrich, M; Döring, G; Lee, J C; Goldmann, D A; Pier, G B

2000-09-29

Staphylococcus aureus and S. epidermidis are among the most common causes of nosocomial infection, and S. aureus is also of major concern to human health due to its occurrence in community-acquired infections. These staphylococcal species are also major pathogens for domesticated animals. We have previously identified poly-N-succinyl beta-1-6 glucosamine (PNSG) as the chemical form of the S. epidermidis capsular polysaccharide/adhesin (PS/A) which mediates adherence of coagulase-negative staphylococci (CoNS) to biomaterials, serves as the capsule for strains of CoNS that express PS/A, and is a target for protective antibodies. We have recently found that PNSG is made by S. aureus as well, where it is an environmentally regulated, in vivo-expressed surface polysaccharide and similarly serves as a target for protective immunity. Only a minority of fresh human clinical isolates of S. aureus elaborate PNSG in vitro but most could be induced to do so under specific in vitro growth conditions. However, by immunofluorescence microscopy, S. aureus cells in infected human sputa and lung elaborated PNSG. The ica genes, previously shown to encode proteins in CoNS that synthesize PNSG, were found by PCR in all S. aureus strains examined, and immunogenic and protective PNSG could be isolated from S. aureus. Active and passive immunization of mice with PNSG protected them against metastatic kidney infections after intravenous inoculation with eight phenotypically PNSG-negative S. aureus. Isolates recovered from kidneys expressed PNSG, but expression was lost with in vitro culture. Strong antibody responses to PNSG were elicited in S. aureus infected mice, and a PNSG-capsule was observed by electron microscopy on isolates directly plated from infected kidneys. PNSG represents a previously unidentified surface polysaccharide of S. aureus that is elaborated during human and animal infection and is a prominent target for protective antibodies.

Cytochemical Localization of Polysaccharides in Dendrobium officinale and the Involvement of DoCSLA6 in the Synthesis of Mannan Polysaccharides

PubMed Central

He, Chunmei; Wu, Kunlin; Zhang, Jianxia; Liu, Xuncheng; Zeng, Songjun; Yu, Zhenming; Zhang, Xinghua; Teixeira da Silva, Jaime A.; Deng, Rufang; Tan, Jianwen; Luo, Jianping; Duan, Jun

2017-01-01

Dendrobium officinale is a precious traditional Chinese medicinal plant because of its abundant polysaccharides found in stems. We determined the composition of water-soluble polysaccharides and starch content in D. officinale stems. The extracted water-soluble polysaccharide content was as high as 35% (w/w). Analysis of the composition of monosaccharides showed that the water-soluble polysaccharides were dominated by mannose, to a lesser extent glucose, and a small amount of galactose, in a molar ratio of 223:48:1. Although starch was also found, its content was less than 10%. This result indicated that the major polysaccharides in D. officinale stems were non-starch polysaccharides, which might be mannan polysaccharides. The polysaccharides formed granules and were stored in plastids similar to starch grains, were localized in D. officinale stems by semi-thin and ultrathin sections. CELLULOSE SYNTHASE-LIKE A (CSLA) family members encode mannan synthases that catalyze the formation of mannan polysaccharides. To determine whether the CSLA gene from D. officinale was responsible for the synthesis of mannan polysaccharides, 35S:DoCSLA6 transgenic lines were generated and characterized. Our results suggest that the CSLA family genes from D. officinale play an important role in the biosynthesis of mannan polysaccharides. PMID:28261235

Aging and the Immune Response to the Haemophilus influenzae Type b Capsular Polysaccharide: Retention of the Dominant Idiotype and Antibody Function in the Elderly

PubMed Central

Lucas, Alexander H.; Reason, Donald C.

1998-01-01

Anti-Haemophilus influenzae b polysaccharide (Hib PS) antibodies elicited in elderly subjects following conjugate vaccination expressed a light-chain variable-region (VL)-associated idiotype and had functional activities similar to those previously observed in children and younger adults. These findings indicate that advanced age is not accompanied by shifts in the major VL component of the Hib PS-specific repertoire or by diminution of the protective function of antibodies. PMID:9529108

Molecular mapping of the cell wall polysaccharides of the human pathogen Streptococcus agalactiae

NASA Astrophysics Data System (ADS)

Beaussart, Audrey; Péchoux, Christine; Trieu-Cuot, Patrick; Hols, Pascal; Mistou, Michel-Yves; Dufrêne, Yves F.

2014-11-01

The surface of many bacterial pathogens is covered with polysaccharides that play important roles in mediating pathogen-host interactions. In Streptococcus agalactiae, the capsular polysaccharide (CPS) is recognized as a major virulence factor while the group B carbohydrate (GBC) is crucial for peptidoglycan biosynthesis and cell division. Despite the important roles of CPS and GBC, there is little information available on the molecular organization of these glycopolymers on the cell surface. Here, we use atomic force microscopy (AFM) and transmission electron microscopy (TEM) to analyze the nanoscale distribution of CPS and GBC in wild-type (WT) and mutant strains of S. agalactiae. TEM analyses reveal that in WT bacteria, peptidoglycan is covered with a very thin (few nm) layer of GBC (the ``pellicle'') overlaid by a 15-45 nm thick layer of CPS (the ``capsule''). AFM-based single-molecule mapping with specific antibody probes shows that CPS is exposed on WT cells, while it is hardly detected on mutant cells impaired in CPS production (ΔcpsE mutant). By contrast, both TEM and AFM show that CPS is over-expressed in mutant cells altered in GBC expression (ΔgbcO mutant), indicating that the production of the two surface glycopolymers is coordinated in WT cells. In addition, AFM topographic imaging and molecular mapping with specific lectin probes demonstrate that removal of CPS (ΔcpsE), but not of GBC (ΔgbcO), leads to the exposure of peptidoglycan, organized into 25 nm wide bands running parallel to the septum. These results indicate that CPS forms a homogeneous barrier protecting the underlying peptidoglycan from environmental exposure, while the presence of GBC does not prevent peptidoglycan detection. This work shows that single-molecule AFM, combined with high-resolution TEM, represents a powerful platform for analysing the molecular arrangement of the cell wall polymers of bacterial pathogens.

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. Copyright © 2016 Elsevier B.V. All rights reserved.

[Imaging manifestations and pathologic basis for hepatic capsular retraction syndrome caused by benign and malignant liver tumors].

PubMed

Ou, Youkuan; Xiao, Enhua; Shang, Quanliang; Chen, Juan

2015-10-01

To investigate the imaging manifestations of CT, MRI and pathological basis for hepatic capsular retraction syndrome caused by benign and malignant liver tumors.
 CT or MRI images and pathological features for hepatic capsular retraction syndrome were retrospectively analyzed in 50 patients with benign and malignant liver tumors. Picture archive and communication system (PACS) was used to observe and compare the morphology, size, width, depth, edge of the capsular retraction and the status of liquid under the liver capsule. The structure, differentiation and proliferation of the tumor were analyzed under the microscope.
 There were malignant liver tumors in 44 patients and benign tumor in 6 patients. The smooth or rough for the edge of capsular retraction was significant difference between the benign tumors and the malignant tumors with three differentiated grades (all P<0.05). There were significant difference in the width and depth for capsule retraction with different amount of fibrous tissues (all P<0.05). The width and depth of capsule retraction were positively correlated to the size of the tumors (r=0.557, 0.309 respectively, both P<0.05).
 Benign and malignant hepatic tumors may appear capsule retraction syndrome, but there are morphological differences between them. The differences are closely related with the lesion size, differentiated degree of tumor and fibrous tissue proliferation.

Identification of a polysaccharide produced by the pyruvate overproducer Candida glabrata CCTCC M202019.

PubMed

Luo, Zhengshan; Liu, Song; Du, Guocheng; Zhou, Jingwen; Chen, Jian

2017-06-01

Candida glabrata has great potential for the accumulation of pyruvate as a preferred strain in pyruvate production by fermentation. However, its substrate conversion rate is relatively low. In this study, a novel polysaccharide containing α-1,4-glucosidic bonds was observed accidentally in screening a high-titer pyruvate strain by atmospheric and room temperature plasma mutagenesis of C. glabrata. Chemical analysis of the partially purified polysaccharide S 4-C10 showed the main components were 1.2% (w/w) protein and 94.2% (w/w) total sugar. Fourier transform infrared and molecular mass distribution analysis indicated that the main component (PSG-2) of S 4-C10 was a small molecular homogeneous protein-bound polysaccharide. Monosaccharide analysis of PSG-2 showed it consisted of glucose, mannose, and fructose. By optimizing the vitamin mix content, 77.6 g L -1 S 4-C10 polysaccharide could be obtained after 72 h fermentation at 30 °C in 500-mL flasks. RT-qPCR analysis showed that transcriptional level of some key genes related to polysaccharide biosynthesis was upregulated compared to that of wild-type strain. By knocking out two most significantly upregulated genes, CAGL0H02695g and CAGL0K10626g, in the wild-type strain, the pyruvate consumption rate was significantly reduced in late pyruvate fermentation phase, while the titer of polysaccharides was reduced by 18.0%. Besides the potential applications of the novel identified polysaccharide, this study provided clues for increasing the conversion ratio of glucose to pyruvate in C. glabrata by further decreasing the accumulation of polysaccharides.

Antibacterials: A sweet vaccine

NASA Astrophysics Data System (ADS)

Bundle, David

2016-03-01

Vaccination with a synthetic glycoconjugate, in combination with the administration of an inhibitor that blocks capsular polysaccharide synthesis in bacteria, could offer an alternative route to combat bacterial infections.

Characteristics and Antitumor Activity of Morchella esculenta Polysaccharide Extracted by Pulsed Electric Field

PubMed Central

Liu, Chao; Sun, Yonghai; Mao, Qian; Guo, Xiaolei; Li, Peng; Liu, Yang; Xu, Na

2016-01-01

Polysaccharides from Morchella esculenta have been proven to be functional and helpful for humans. The purpose of this study was to investigate the chemical structure and anti-proliferating and antitumor activities of a Morchella esculenta polysaccharide (MEP) extracted by pulsed electric field (PEF) in submerged fermentation. The endo-polysaccharide was separated and purified by column chromatography and Gel permeation chromatography, and analyzed by gas chromatography. The MEP with an average molecular weight of 81,835 Da consisted of xylose, glucose, mannose, rhamnose and galactose at the ratio of 5.4:5.0:6.5:7.8:72.3. Structure of MEP was further analyzed by Fourier-transform infrared spectroscopy and 1H and 13C liquid-state nuclear magnetic resonance spectroscopy. Apoptosis tests proved that MEP could inhibit the proliferation and growth of human colon cancer HT-29 cells in a time- and dose-dependent manner within 48 h. This study provides more information on chemical structure of anti-proliferating polysaccharides isolated from Morchella esculenta. PMID:27338370

Enzymatic method for improving the injectability of polysaccharides

DOEpatents

Griffith, William L.; Compere, Alicia L.; Holleman, James W.

1982-01-01

A method for enhancing the ability of polysaccharides in aqueous solution to flow through a porous medium comprises contacting the polysaccharides with an endoenzyme capable of hydrolyzing at least one of the linkages of the sugar units of the polysaccharides and maintaining the polysaccharides in contact with the enzyme under hydrolysis conditions for a time sufficient to decrease the tendency of the polysaccharides to plug the porous medium yet insufficient to decrease the viscosity of the aqueous polysaccharides by more than 25%. The partially hydrolyzed polysaccharides are useful as thickening agents for flooding water used to recover oil from oil-containing subterranean formations.

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.

Platinum concentration in silicone breast implant material and capsular tissue by ICP-MS.

PubMed

Maharaj, S V M

2004-09-01

Inductively coupled plasma-mass spectrometry (ICP-MS) was used to determine the concentration of platinum (Pt) in silicone breast implant gel (range, 0.26-48.90 microg g(-1) Pt; n=15), elastomer (range, 3.05-28.78 microg g(-1) Pt; n=7), double lumen (range, 5.79-125.27 microg g(-1) Pt; n=7), foam (range, 5.79-8.36 microg g(-1) Pt; n=2), and capsular tissue (range, 0.003-0.272 microg g(-1) Pt; n=15). The results show that very high levels of Pt are present in the encasing elastomer, double lumen, and foam envelope materials. Silicone breast implants can be a source of significant Pt exposure for individuals with these implants.