Xylella fastidiosa Afimbrial Adhesins Mediate Cell Transmission to Plants by Leafhopper Vectors▿

PubMed Central

Killiny, Nabil; Almeida, Rodrigo P. P.

2009-01-01

The interactions between the economically important plant-pathogenic bacterium Xylella fastidiosa and its leafhopper vectors are poorly characterized. We used different approaches to determine how X. fastidiosa cells interact with the cuticular surface of the foreguts of vectors. We demonstrate that X. fastidiosa binds to different polysaccharides with various affinities and that these interactions are mediated by cell surface carbohydrate-binding proteins. In addition, competition assays showed that N-acetylglucosamine inhibits bacterial adhesion to vector foregut extracts and intact wings, demonstrating that attachment to leafhopper surfaces is affected in the presence of specific polysaccharides. In vitro experiments with several X. fastidiosa knockout mutants indicated that hemagglutinin-like proteins are associated with cell adhesion to polysaccharides. These results were confirmed with biological experiments in which hemagglutinin-like protein mutants were transmitted to plants by vectors at lower rates than that of the wild type. Furthermore, although these mutants were defective in adhesion to the cuticle of vectors, their growth rate once attached to leafhoppers was similar to that of the wild type, suggesting that these proteins are important for initial adhesion of X. fastidiosa to leafhoppers. We propose that X. fastidiosa colonization of leafhopper vectors is a complex, stepwise process similar to the formation of biofilms on surfaces. PMID:19011051

Aqueous extracts and polysaccharides from Marshmallow roots (Althea officinalis L.): cellular internalisation and stimulation of cell physiology of human epithelial cells in vitro.

PubMed

Deters, Alexandra; Zippel, Janina; Hellenbrand, Nils; Pappai, Dirk; Possemeyer, Cathleen; Hensel, Andreas

2010-01-08

Aqueous extracts from the roots of Althea officinalis L. (Malvaceae) are widely used for treatment of irritated mucosa. The clinical proven effects are related to the presence of bioadhesive and mucilaginous polysaccharides from the rhamnogalacturonan type, leading to the physical formation of mucin-like on top of the irritated tissues. No data are available if the extracts or the polysaccharides from these extract exert an active influence on mucosal or connective tissue cells, in order to initiated changes in cell physiology, useful for better tissue regeneration. In vitro investigations of aqueous A. officinalis extract AE and raw polysaccharides (RPS) on epithelial KB cells and primary dermal human fibroblasts (pNHF) using WST1 vitality test and BrdU proliferation ELISA. Gene expression analysis by microarray from KB cells. Internalisation studies of polysaccharides were performed by laser scanning microscopy. AE (1, 10 microg/mL) had stimulating effect on cell viability and proliferation of epithelial KB cells. RPS (1, 10 microg/mL) stimulated cell vitality of epithelial cells significantly without triggering the cells into higher proliferation status. Neither AE nor RPS had any effect on fibroblasts. FITC-labeled RPS was shown to be internalised into epithelial cells, but not into fibroblasts. FITC-RPS was shown to form bioadhesive layers on the cell surface of dermal fibroblasts. Microarray analysis indicated an up-regulation of genes related to cell adhesion proteins, growth regulators, extracellular matrix, cytokine release and apoptosis. Aqueous extracts and polysaccharides from the roots of A. officinalis are effective stimulators of cell physiology of epithelial cells which can prove the traditional use of Marshmallow preparations for treatment of irritated mucous membranes within tissue regeneration. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Bioactivities and extraction optimization of crude polysaccharides from the fruits and leaves of Rubus chingii Hu.

PubMed

Zhang, Tian-Tian; Lu, Chuan-Li; Jiang, Jian-Guo; Wang, Min; Wang, Dong-Mei; Zhu, Wei

2015-10-05

Polysaccharides of Rubus chingii Hu fruit and leaf were extracted to compare their antioxidant, anti-inflammatory, and anticancer activities against breast cancer cells MCF-7 and liver cancer cells Bel-7402. Results showed that all the tested bioactivities of polysaccharides from leaf (L-Ps) were better than those of polysaccharides from fruit (F-Ps). Response surface methodology was then used to optimize the extraction conditions of polysaccharides from leaf. Additionally, polysaccharides from fruit and leaf were characterized and their contents of total sugars, proteins and uronic acid were compared. It was found that polysaccharides from fruit and leaf were similar in IR and UV absorption, but significantly different in contents of total sugars, protein and uronic acid. Their elution profiles of DEAE-Sepharose fast flow column were different too. The main peak of polysaccharides from fruit was eluted with 0.3 mol/l NaCl solution and the main peak of polysaccharides from leaf was eluted with deionized water. The differences between the two polysaccharides may be responsible for their differences in bioactivities. Further studies are required to explore their complete structural characteristics, structure-activity relationship and the mechanism of their activities. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

Structure, cell wall elasticity and polysaccharide properties of living yeast cells, as probed by AFM

NASA Astrophysics Data System (ADS)

Alsteens, David; Dupres, Vincent; McEvoy, Kevin; Wildling, Linda; Gruber, Hermann J.; Dufrêne, Yves F.

2008-09-01

Although the chemical composition of yeast cell walls is known, the organization, assembly, and interactions of the various macromolecules remain poorly understood. Here, we used in situ atomic force microscopy (AFM) in three different modes to probe the ultrastructure, cell wall elasticity and polymer properties of two brewing yeast strains, i.e. Saccharomyces carlsbergensis and S. cerevisiae. Topographic images of the two strains revealed smooth and homogeneous cell surfaces, and the presence of circular bud scars on dividing cells. Nanomechanical measurements demonstrated that the cell wall elasticity of S. carlsbergensis is homogeneous. By contrast, the bud scar of S. cerevisiae was found to be stiffer than the cell wall, presumably due to the accumulation of chitin. Notably, single molecule force spectroscopy with lectin-modified tips revealed major differences in polysaccharide properties of the two strains. Polysaccharides were clearly more extended on S. cerevisiae, suggesting that not only oligosaccharides, but also polypeptide chains of the mannoproteins were stretched. Consistent with earlier cell surface analyses, these findings may explain the very different aggregation properties of the two organisms. This study demonstrates the power of using multiple complementary AFM modalities for probing the organization and interactions of the various macromolecules of microbial cell walls.

The Cryptococcus neoformans Capsule: a Sword and a Shield

PubMed Central

O'Meara, Teresa R.

2012-01-01

Summary: The human fungal pathogen Cryptococcus neoformans is characterized by its ability to induce a distinct polysaccharide capsule in response to a number of host-specific environmental stimuli. The induction of capsule is a complex biological process encompassing regulation at multiple steps, including the biosynthesis, transport, and maintenance of the polysaccharide at the cell surface. By precisely regulating the composition of its cell surface and secreted polysaccharides, C. neoformans has developed intricate ways to establish chronic infection and dormancy in the human host. The plasticity of the capsule structure in response to various host conditions also underscores the complex relationship between host and parasite. Much of this precise regulation of capsule is achieved through the transcriptional responses of multiple conserved signaling pathways that have been coopted to regulate this C. neoformans-specific virulence-associated phenotype. This review focuses on specific host stimuli that trigger the activation of the signal transduction cascades and on the downstream transcriptional responses that are required for robust encapsulation around the cell. PMID:22763631

Selective reactivity of monochloramine with extracellular matrix components affects the disinfection of biofilm and detached clusters.

PubMed

Xue, Zheng; Lee, Woo Hyoung; Coburn, Kimberly M; Seo, Youngwoo

2014-04-01

The efficiency of monochloramine disinfection was dependent on the quantity and composition of extracellular polymeric substances (EPS) in biofilms, as monochloramine has a selective reactivity with proteins over polysaccharides. Biofilms with protein-based (Pseudomonas putida) and polysaccharide based EPS (Pseudomonas aeruginosa), as well as biofilms with varied amount of polysaccharide EPS (wild-type and mutant P. aeruginosa), were compared. The different reactivity of EPS components with monochloramine influenced disinfectant penetration, biofilm inactivation, as well as the viability of detached clusters. Monochloramine transport profiling measured by a chloramine-sensitive microelectrode revealed a broader diffusion boundary layer between bulk and biofilm surface in the P. putida biofilm compared to those of P. aeruginosa biofilms. The reaction with proteins in P. putida EPS multiplied both the time and the monochloramine mass required to achieve a full biofilm penetration. Cell viability in biofilms was also spatially influenced by monochloramine diffusion and reaction within biofilms, showing a lower survival in the surface section and a higher persistence in the middle section of the P. putida biofilm compared to the P. aeruginosa biofilms. While polysaccharide EPS promoted biofilm cell viability by obstructing monochloramine reactive sites on bacterial cells, protein EPS hindered monochloramine penetration by reacting with monochloramine and reduced its concentration within biofilms. Furthermore, the persistence of bacterial cells detached from biofilm (over 70% for P. putida and ∼40% for polysaccharide producing P. aeruginosa) suggested that currently recommended monochloramine residual levels may underestimate the risk of water quality deterioration caused by biofilm detachment.

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

An in vitro assessment of titanium functionalized with polysaccharides conjugated with vascular endothelial growth factor for enhanced osseointegration and inhibition of bacterial adhesion.

PubMed

Hu, Xuefeng; Neoh, Koon-Gee; Shi, Zhilong; Kang, En-Tang; Poh, Chyekhoon; Wang, Wilson

2010-12-01

The long-term success of orthopedic implants may be compromised by defective osseointegration and bacterial infection. An effective approach to minimize implant failure would be to modify the surface of the implant to make it habitable for bone-forming cells and anti-infective at the same time. In this in vitro study, the surfaces of titanium (Ti) substrates were functionalized by first covalently grafting either dopamine followed by carboxymethyl chitosan (CMCS) or hyaluronic acid-catechol (HAC). Vascular endothelial growth factor (VEGF) was then conjugated to the polysaccharide-grafted surface. Antibacterial assay with Staphylococcus aureus (S. aureus) showed that the polysaccharide-modified substrates significantly decrease bacterial adhesion. The CMCS-functionalized Ti demonstrated better antibacterial property than the HAC-functionalized Ti since CMCS is bactericidal while HA only inhibits the adhesion of bacteria without killing them. Osteoblast attachment, as well as alkaline phosphatase (ALP) activity and calcium deposition were enhanced by the immobilized VEGF on the polysaccharide-grafted Ti. Thus, Ti substrates modified with polysaccharides conjugated with VEGF can promote osteoblast functions and concurrently reduce bacterial adhesion. Since VEGF is also known to enhance angiogenesis, the VEGF-polysaccharide functionalized substrates will have promising applications in the orthopedic field. Copyright © 2010 Elsevier Ltd. All rights reserved.

The pgaABCD Locus of Escherichia coli Promotes the Synthesis of a Polysaccharide Adhesin Required for Biofilm Formation

PubMed Central

Wang, Xin; Preston, James F.; Romeo, Tony

2004-01-01

Production of a polysaccharide matrix is a hallmark of bacterial biofilms, but the composition of matrix polysaccharides and their functions are not widely understood. Previous studies of the regulation of Escherichia coli biofilm formation suggested the involvement of an unknown adhesin. We now establish that the pgaABCD (formerly ycdSRQP) locus affects biofilm development by promoting abiotic surface binding and intercellular adhesion. All of the pga genes are required for optimal biofilm formation under a variety of growth conditions. A pga-dependent cell-bound polysaccharide was isolated and determined by nuclear magnetic resonance analyses to consist of unbranched β-1,6-N-acetyl-d-glucosamine, a polymer previously unknown from the gram-negative bacteria but involved in adhesion by staphylococci. The pga genes are predicted to encode envelope proteins involved in synthesis, translocation, and possibly surface docking of this polysaccharide. As predicted, if poly-β-1,6-GlcNAc (PGA) mediates cohesion, metaperiodate caused biofilm dispersal and the release of intact cells, whereas treatment with protease or other lytic enzymes had no effect. The pgaABCD operon exhibits features of a horizontally transferred locus and is present in a variety of eubacteria. Therefore, we propose that PGA serves as an adhesin that stabilizes biofilms of E. coli and other bacteria. PMID:15090514

Nanoscale biophysical properties of the cell surface galactosaminogalactan from the fungal pathogen Aspergillus fumigatus

NASA Astrophysics Data System (ADS)

Beaussart, Audrey; El-Kirat-Chatel, Sofiane; Fontaine, Thierry; Latgé, Jean-Paul; Dufrêne, Yves F.

2015-09-01

Many fungal pathogens produce cell surface polysaccharides that play essential roles in host-pathogen interactions. In Aspergillus fumigatus, the newly discovered polysaccharide galactosaminogalactan (GAG) mediates adherence to a variety of substrates through molecular mechanisms that are poorly understood. Here we use atomic force microscopy to unravel the localization and adhesion of GAG on living fungal cells. Using single-molecule imaging with tips bearing anti-GAG antibodies, we found that GAG is massively exposed on wild-type (WT) germ tubes, consistent with the notion that this glycopolymer is secreted by the mycelium of A. fumigatus, while it is lacking on WT resting conidia and on germ tubes from a mutant (Δuge3) deficient in GAG. Imaging germ tubes with tips bearing anti-β-glucan antibodies shows that exposure of β-glucan is strongly increased in the Δuge3 mutant, indicating that this polysaccharide is masked by GAG during hyphal growth. Single-cell force measurements show that expression of GAG on germ tubes promotes specific adhesion to pneumocytes and non-specific adhesion to hydrophobic substrates. These results provide a molecular foundation for the multifunctional adhesion properties of GAG, thus suggesting it could be used as a potential target in anti-adhesion therapy and immunotherapy. Our methodology represents a powerful approach for characterizing the nanoscale organization and adhesion of cell wall polysaccharides during fungal morphogenesis, thereby contributing to increase our understanding of their role in biofilm formation and immune responses.

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.

Structural analysis of cell wall polysaccharides using PACE

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

Mortimer, Jennifer C.

The plant cell wall is composed of many complex polysaccharides. The composition and structure of the polysaccharides affect various cell properties including cell shape, cell function and cell adhesion. Many techniques to characterize polysaccharide structure are complicated, requiring expensive equipment and specialized operators e.g. NMR, MALDI-MS. PACE (Polysaccharide Analysis using Carbohydrate gel Electrophoresis) uses a simple, rapid technique to analyze polysaccharide quantity and structure (Goubet et al. 2002). Whilst the method here describes xylan analysis, it can be applied (by use of the appropriate glycosyl hydrolase) to any cell wall polysaccharide.

Microbially induced separation of quartz from hematite using sulfate reducing bacteria.

PubMed

Prakasan, M R Sabari; Natarajan, K A

2010-07-01

Cells and metabolic products of Desulfovibrio desulfuricans were successfully used to separate quartz from hematite through environmentally benign microbially induced flotation. Bacterial metabolic products such as extracellular proteins and polysaccharides were isolated from both unadapted and mineral-adapted bacterial metabolite and their basic characteristics were studied in order to get insight into the changes brought about on bioreagents during adaptation. Interaction between bacterial cells and metabolites with minerals like hematite and quartz brought about significant surface-chemical changes on both the minerals. Quartz was rendered more hydrophobic, while hematite became more hydrophilic after biotreatment. The predominance of bacterial polysaccharides on interacted hematite and of proteins on quartz was responsible for the above surface-chemical changes, as attested through adsorption studies. Surface-chemical changes were also observed on bacterial cells after adaptation to the above minerals. Selective separation of quartz from hematite was achieved through interaction with quartz-adapted bacterial cells and metabolite. Mineral-specific proteins secreted by quartz-adapted cells were responsible for conferment of hydrophobicity on quartz resulting in enhanced separation from hematite through flotation. 2010 Elsevier B.V. All rights reserved.

Electro-optical study of the exposure of Azospirillum brasilense carbohydrate epitopes.

PubMed

Guliy, Olga I; Matora, Larisa Yu; Dykman, Lev A; Staroverov, Sergey A; Burygin, Gennady L; Bunin, Viktor D; Burov, Andrei M; Ignatov, Oleg V

2015-01-01

The exposure of Azospirillum brasilense carbohydrate epitopes was investigated by electro-optical analysis of bacterial cell suspensions. To study changes in the electro-optical (EO) properties of the suspensions, we used antibodies generated to the complete lipopolysaccharide of A. brasilense type strain Sp7 and also antibodies to the smooth and rough O polysaccharides of Sp7. After 18 hr of culture growth, the EO signal of the suspension treated with antibodies to smooth O polysaccharide was approximately 20% lower than that of the suspension treated with antibodies to complete lipopolysaccharide (control). After 72 hr of culture growth, the strongest EO signal was observed for the cells treated with antibodies to rough O polysaccharide (approximately 46% greater than the control), whereas for the cells treated with antibodies to smooth O polysaccharide, it was much lower (approximately 23% of the control). These data were confirmed by electron microscopy. The results of the study may have importance for the rapid evaluation of changes in lipopolysaccharide form in microbial biotechnology, when the antigenic composition of the bacterial surface requires close control.

The Pseudomonas aeruginosa PSL Polysaccharide Is a Social but Noncheatable Trait in Biofilms

PubMed Central

Roberts, Aled E. L.; Kragh, Kasper N.; Gordon, Vernita D.; Hutchison, Jaime; Allen, Rosalind J.; Melaugh, Gavin; Bjarnsholt, Thomas; West, Stuart A.

2017-01-01

ABSTRACT Extracellular polysaccharides are compounds secreted by microorganisms into the surrounding environment, and they are important for surface attachment and maintaining structural integrity within biofilms. The social nature of many extracellular polysaccharides remains unclear, and it has been suggested that they could function as either cooperative public goods or as traits that provide a competitive advantage. Here, we empirically tested the cooperative nature of the PSL polysaccharide, which is crucial for the formation of biofilms in Pseudomonas aeruginosa. We show that (i) PSL is not metabolically costly to produce; (ii) PSL provides population-level benefits in biofilms, for both growth and antibiotic tolerance; (iii) the benefits of PSL production are social and are shared with other cells; (iv) the benefits of PSL production appear to be preferentially directed toward cells which produce PSL; (v) cells which do not produce PSL are unable to successfully exploit cells which produce PSL. Taken together, this suggests that PSL is a social but relatively nonexploitable trait and that growth within biofilms selects for PSL-producing strains, even when multiple strains are on a patch (low relatedness at the patch level). PMID:28634237

Structure and genetics of the O-specific polysaccharide of Escherichia coli O27.

PubMed

Perepelov, Andrei V; Chen, Tingting; Senchenkova, Sofya N; Filatov, Andrei V; Song, Jingjie; Shashkov, Alexander S; Liu, Bin; Knirel, Yuriy A

2018-02-01

The O-specific polysaccharide (O-antigen) is a part of the lipopolysaccharide on the cell surface of Gram-negative bacteria. The O-polysaccharide was obtained by mild acid hydrolysis of the lipopolysaccharide of Escherichia coli O27 and studied by sugar analysis and Smith degradation along with 1 H and 13 C NMR spectroscopy. The following structure of the branched hexasaccharide repeating unit was established, which is unique among known structures of bacterial polysaccharides:where GlcA is non-stoichiometrically O-acetylated at position 3 (∼22%) or 4 (∼37%). Functions of genes in the O-antigen gene cluster of E. coli O27 were tentatively assigned by comparison with sequences in the available databases and found to be consistent with the O-polysaccharide structure. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Mycoplasma agalactiae Secretion of β-(1→6)-Glucan, a Rare Polysaccharide in Prokaryotes, Is Governed by High-Frequency Phase Variation

PubMed Central

Baranowski, E.; Pau-Roblot, C.; Sagné, E.; Citti, C.

2016-01-01

ABSTRACT Mycoplasmas are minimal, wall-less bacteria but have retained the ability to secrete complex carbohydrate polymers that constitute a glycocalyx. In members of the Mycoplasma mycoides cluster, which are important ruminant pathogens, the glycocalyx includes both cell-attached and cell-free polysaccharides. This report explores the potential secretion of polysaccharides by M. agalactiae, another ruminant pathogen that belongs to a distant phylogenetic group. Comparative genomic analyses showed that M. agalactiae possesses all the genes required for polysaccharide secretion. Notably, a putative synthase gene (gsmA) was identified, by in silico reconstruction of the biosynthetic pathway, that could be involved in both polymerization and export of the carbohydrate polymers. M. agalactiae polysaccharides were then purified in vitro and found to be mainly cell attached, with a linear β-(1→6)-glucopyranose structure [β-(1→6)-glucan]. Secretion of β-(1→6)-glucan was further shown to rely on the presence of a functional gsmA gene, whose expression is subjected to high-frequency phase variation. This event is governed by the spontaneous intraclonal variation in length of a poly(G) tract located in the gsmA coding sequence and was shown to occur in most of the M. agalactiae clinical isolates tested in this study. M. agalactiae susceptibility to serum-killing activity appeared to be dictated by ON/OFF switching of β-(1→6)-glucan secretion, suggesting a role of this phenomenon in survival of the pathogen when it invades the host bloodstream. Finally, β-(1→6)-glucan secretion was not restricted to M. agalactiae but was detected also in M. mycoides subsp. capri PG3T, another pathogen of small ruminants. IMPORTANCE Many if not all bacteria are able to secrete polysaccharides, either attached to the cell surface or exported unbound into the extracellular environment. Both types of polysaccharides can play a role in bacterium-host interactions. Mycoplasmas are 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

Complete structure of the cell surface polysaccharide of Streptococcus oralis ATCC 10557: A receptor for lectin-mediated interbacterial adherence

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

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

1991-07-02

Lectin-carbohydrate binding is known to play an important role in a number of different cell-cell interactions including those between certain species of oral streptococci and actinomyces that colonize teeth. The cell wall polysaccharides of Streptococcus oralis ATCC 10557, S. oralis 34, and Streptococcus mitis J22, although not identical antigenically, each function as a receptor molecule for the galactose and N-acetylgalactosamine reactive fimbrial lectins of Actinomyces viscosus and Actinomyces naeslundii. Carbohydrate analysis of the receptor polysaccharide isolated from S. oralis ATCC 10557 shows galactose (3 mol), glucose (1 mol), GalNAc (1 mol), and rhamnose (1 mol). {sup 1}H NMR spectra ofmore » the polysaccharide show that is partially O-acetylated. Analysis of the {sup 1}H NMR spectrum of the de-O-acetylated polysaccharide shows that it is composed of repeating subunits containing six monosaccharides and that the subunits are joined by a phosphodiester linkage. The {sup 1}H and {sup 13}C NMR spectra were completely assigned by two-dimensional homonuclear correlation methods and by {sup 1}H-detected heteronuclear multiple-quantum correlation ({sup 1}H({sup 13}C)HMQC). The complete {sup 1}H and {sup 13}C assignment of the native polysaccharide was carried out by the same techniques augmented by a {sup 13}C-coupled hybrid HMQC-COSY method, which is shown to be especially useful for carbohydrates in which strong coupling and overlapping peaks in the {sup 1}H spectrum pose difficulties.« less

Solid-State (13)C NMR Delineates the Architectural Design of Biopolymers in Native and Genetically Altered Tomato Fruit Cuticles.

PubMed

Chatterjee, Subhasish; Matas, Antonio J; Isaacson, Tal; Kehlet, Cindie; Rose, Jocelyn K C; Stark, Ruth E

2016-01-11

Plant cuticles on outer fruit and leaf surfaces are natural macromolecular composites of waxes and polyesters that ensure mechanical integrity and mitigate environmental challenges. They also provide renewable raw materials for cosmetics, packaging, and coatings. To delineate the structural framework and flexibility underlying the versatile functions of cutin biopolymers associated with polysaccharide-rich cell-wall matrices, solid-state NMR spectra and spin relaxation times were measured in a tomato fruit model system, including different developmental stages and surface phenotypes. The hydrophilic-hydrophobic balance of the cutin ensures compatibility with the underlying polysaccharide cell walls; the hydroxy fatty acid structures of outer epidermal cutin also support deposition of hydrophobic waxes and aromatic moieties while promoting the formation of cell-wall cross-links that rigidify and strengthen the cuticle composite during fruit development. Fruit cutin-deficient tomato mutants with compromised microbial resistance exhibit less efficient local and collective biopolymer motions, stiffening their cuticular surfaces and increasing their susceptibility to fracture.

Enhanced Differentiation of Human Preosteoblasts on Electrospun Blend Fiber Mats of Polydioxanone and Anionic Sulfated Polysaccharides

PubMed Central

2017-01-01

The viability and differentiation of SaOS-2 preosteoblasts on fiber mats of blends comprising of the biodegradable poly(ester-ether) polydioxanone (PDX) and the sulfate-containing anionic polysaccharides kappa-carrageenan (KCG) and fucoidan (FUC) were investigated for a range of different blend compositions. The detailed analysis of the blend nanofiber properties revealed a different degree of miscibility of PDX and the polysaccharide leading to a different enrichment at the surface of the blend nanofibers, which were observed to be stable in phosphate buffer solution (PBS) for up to 5 weeks. The fibrous mats of PDX/FUC led to the highest osteogenic differentiation with very good cell viability. The electrospun blend fibers also supported human-induced pluripotent stem (iPS) cells and iPS cell-derived embryoid bodies with high cell viability, which underlines the potential of these novel blend fiber systems for optimized performance in bone tissue engineering applications. PMID:29285521

Attachment of Salmonella strains to a plant cell wall model is modulated by surface characteristics and not by specific carbohydrate interactions.

PubMed

Tan, Michelle Sze-Fan; Moore, Sean C; Tabor, Rico F; Fegan, Narelle; Rahman, Sadequr; Dykes, Gary A

2016-09-15

Processing of fresh produce exposes cut surfaces of plant cell walls that then become vulnerable to human foodborne pathogen attachment and contamination, particularly by Salmonella enterica. Plant cell walls are mainly composed of the polysaccharides cellulose, pectin and hemicelluloses (predominantly xyloglucan). Our previous work used bacterial cellulose-based plant cell wall models to study the interaction between Salmonella and the various plant cell wall components. We demonstrated that Salmonella attachment was favoured in the presence of pectin while xyloglucan had no effect on its attachment. Xyloglucan significantly increased the attachment of Salmonella cells to the plant cell wall model only when it was in association with pectin. In this study, we investigate whether the plant cell wall polysaccharides mediate Salmonella attachment to the bacterial cellulose-based plant cell wall models through specific carbohydrate interactions or through the effects of carbohydrates on the physical characteristics of the attachment surface. We found that none of the monosaccharides that make up the plant cell wall polysaccharides specifically inhibit Salmonella attachment to the bacterial cellulose-based plant cell wall models. Confocal laser scanning microscopy showed that Salmonella cells can penetrate and attach within the tightly arranged bacterial cellulose network. Analysis of images obtained from atomic force microscopy revealed that the bacterial cellulose-pectin-xyloglucan composite with 0.3 % (w/v) xyloglucan, previously shown to have the highest number of Salmonella cells attached to it, had significantly thicker cellulose fibrils compared to other composites. Scanning electron microscopy images also showed that the bacterial cellulose and bacterial cellulose-xyloglucan composites were more porous when compared to the other composites containing pectin. Our study found that the attachment of Salmonella cells to cut plant cell walls was not mediated by specific carbohydrate interactions. This suggests that the attachment of Salmonella strains to the plant cell wall models were more dependent on the structural characteristics of the attachment surface. Pectin reduces the porosity and space between cellulose fibrils, which then forms a matrix that is able to retain Salmonella cells within the bacterial cellulose network. When present with pectin, xyloglucan provides a greater surface for Salmonella cells to attach through the thickening of cellulose fibrils.

Immunogold scanning electron microscopy can reveal the polysaccharide architecture of xylem cell walls

PubMed Central

Sun, Yuliang; Juzenas, Kevin

2017-01-01

Abstract Immunofluorescence microscopy (IFM) and immunogold transmission electron microscopy (TEM) are the two main techniques commonly used to detect polysaccharides in plant cell walls. Both are important in localizing cell wall polysaccharides, but both have major limitations, such as low resolution in IFM and restricted sample size for immunogold TEM. In this study, we have developed a robust technique that combines immunocytochemistry with scanning electron microscopy (SEM) to study cell wall polysaccharide architecture in xylem cells at high resolution over large areas of sample. Using multiple cell wall monoclonal antibodies (mAbs), this immunogold SEM technique reliably localized groups of hemicellulosic and pectic polysaccharides in the cell walls of five different xylem structures (vessel elements, fibers, axial and ray parenchyma cells, and tyloses). This demonstrates its important advantages over the other two methods for studying cell wall polysaccharide composition and distribution in these structures. In addition, it can show the three-dimensional distribution of a polysaccharide group in the vessel lateral wall and the polysaccharide components in the cell wall of developing tyloses. This technique, therefore, should be valuable for understanding the cell wall polysaccharide composition, architecture and functions of diverse cell types. PMID:28398585

Exploring the Role of Cell Wall-Related Genes and Polysaccharides during Plant Development.

PubMed

Tucker, Matthew R; Lou, Haoyu; Aubert, Matthew K; Wilkinson, Laura G; Little, Alan; Houston, Kelly; Pinto, Sara C; Shirley, Neil J

2018-05-31

The majority of organs in plants are not established until after germination, when pluripotent stem cells in the growing apices give rise to daughter cells that proliferate and subsequently differentiate into new tissues and organ primordia. This remarkable capacity is not only restricted to the meristem, since maturing cells in many organs can also rapidly alter their identity depending on the cues they receive. One general feature of plant cell differentiation is a change in cell wall composition at the cell surface. Historically, this has been viewed as a downstream response to primary cues controlling differentiation, but a closer inspection of the wall suggests that it may play a much more active role. Specific polymers within the wall can act as substrates for modifications that impact receptor binding, signal mobility, and cell flexibility. Therefore, far from being a static barrier, the cell wall and its constituent polysaccharides can dictate signal transmission and perception, and directly contribute to a cell's capacity to differentiate. In this review, we re-visit the role of plant cell wall-related genes and polysaccharides during various stages of development, with a particular focus on how changes in cell wall machinery accompany the exit of cells from the stem cell niche.

Oral Administration of N-Acetyl-D-Glucosamine Polymer Particles Down-Regulates Airway Allergic Responses

DTIC Science & Technology

2007-03-01

deoxygalactose and galactose, respectively. Relatively less mITLN-1 was eluted by these monosaccharides . The oligomeric Hu/Mo chimeric ITLN-1 had...Abeygunawardana, C., Bush, C. A. and Cisar, J. O. (1991) Complete structure of the cell surface polysaccharide of Streptococcus oralis C104: a 600-MHz NMR...Hoogerhout, P. and van Boom, J. H. (1988) (1-5)-linked beta-D-galactofuranosides are immunodominant in extracellular polysaccharides of

Chitin: a cell-surface component of Phytomonas françai.

PubMed

Nakamura, C V; Esteves, M J; Andrade, A F; Alviano, C S; de Souza, W; Angluster, J

1993-01-01

The occurrence of chitin as a structural component of the surface of the phytopathogenic protozoan Phytomonas françai was demonstrated by paper and gas-liquid chromatographic analysis of the products of enzymatic and chemical hydrolysis of alkali-resistant polysaccharides, lectin binding, glycosidase digestion, and infrared spectra. Chitin was characterized by its insolubility in hot alkali and chromatographic immobility as well as by the release of glucosamine on hydrolysis with strong acid and of N-acetylglucosamine (GlcNAc) on hydrolysis with chitinase. The presence of chitin was also shown directly by binding of wheat-germ agglutinin (WGA), which recognizes GlcNAc units, to the parasite surface. Fluorescein-labeled WGA binding was completely abolished by treatment with chitinase. This effect was specific since it could be prevented by incubating the enzyme with chitin before treatment of the phytomonads. These findings indicate that chitin is an exposed cell-surface polysaccharide in Phytomonas françai. The data were confirmed by the infrared spectrum of an alkali-insoluble residue, which showed a pattern typical of chitin.

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 structures in pathogenic Cryptococcus species and environmental species share similar features, but also manifest significant difference that could influence their potential to virulence.

Layer-by-layer buildup of polysaccharide-containing films: Physico-chemical properties and mesenchymal stem cells adhesion.

PubMed

Kulikouskaya, Viktoryia I; Pinchuk, Sergei V; Hileuskaya, Kseniya S; Kraskouski, Aliaksandr N; Vasilevich, Irina B; Matievski, Kirill A; Agabekov, Vladimir E; Volotovski, Igor D

2018-03-22

Layer-by-Layer assembled polyelectrolyte films offer the opportunity to control cell attachment and behavior on solid surfaces. In the present study, multilayer films based on negatively charged biopolymers (pectin, dextran sulfate, carboxymethylcellulose) and positively charged polysaccharide chitosan or synthetic polyelectrolyte polyethyleneimine has been prepared and evaluated. Physico-chemical properties of the formed multilayer films, including their growth, morphology, wettability, stability, and mechanical properties, have been studied. We demonstrated that chitosan-containing films are characterized by the linear growth, the defect-free surface, and predominantly viscoelastic properties. When chitosan is substituted for the polyethyleneimine in the multilayer system, the properties of the formed films are significantly altered: the rigidity and surface roughness increases, the film growth acquires the exponential character. The multilayer films were subsequently used for culturing mesenchymal stem cells. It has been determined that stem cells effectively adhered to chitosan-containing films and formed on them the monolayer culture of fibroblast-like cells with high viability. Our results show that cell attachment is a complex process which is not only governed by the surface functionality because one of the key parameter effects on cell adhesion is the stiffness of polyelectrolyte multilayer films. We therefore propose our Layer-by-Layer films for applications in tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2018. © 2018 Wiley Periodicals, Inc.

Strain-Specific Features of Extracellular Polysaccharides and Their Impact on Lactobacillus plantarum-Host Interactions.

PubMed

Lee, I-Chiao; Caggianiello, Graziano; van Swam, Iris I; Taverne, Nico; Meijerink, Marjolein; Bron, Peter A; Spano, Giuseppe; Kleerebezem, Michiel

2016-07-01

Lactobacilli are found in diverse environments and are widely applied as probiotic, health-promoting food supplements. Polysaccharides are ubiquitously present on the cell surface of lactobacilli and are considered to contribute to the species- and strain-specific probiotic effects that are typically observed. Two Lactobacillus plantarum strains, SF2A35B and Lp90, have an obvious ropy phenotype, implying high extracellular polysaccharide (EPS) production levels. In this work, we set out to identify the genes involved in EPS production in these L. plantarum strains and to demonstrate their role in EPS production by gene deletion analysis. A model L. plantarum strain, WCFS1, and its previously constructed derivative that produced reduced levels of EPS were included as reference strains. The constructed EPS-reduced derivatives were analyzed for the abundance and sugar compositions of their EPS, revealing cps2-like gene clusters in SF2A35B and Lp90 responsible for major EPS production. Moreover, these mutant strains were tested for phenotypic characteristics that are of relevance for their capacity to interact with the host epithelium in the intestinal tract, including bacterial surface properties as well as survival under the stress conditions encountered in the gastrointestinal tract (acid and bile stress). In addition, the Toll-like receptor 2 (TLR2) signaling and immunomodulatory capacities of the EPS-negative derivatives and their respective wild-type strains were compared, revealing strain-specific impacts of EPS on the immunomodulatory properties. Taken together, these experiments illustrate the importance of EPS in L. plantarum strains as a strain-specific determinant in host interaction. This study evaluates the role of extracellular polysaccharides that are produced by different strains of Lactobacillus plantarum in the determination of the cell surface properties of these bacteria and their capacity to interact with their environment, including their signaling to human host cells. The results clearly show that the consequences of removal of these polysaccharides are very strain specific, illustrating the diverse and unpredictable roles of these polysaccharides in the environmental interactions of these bacterial strains. In the context of the use of lactobacilli as health-promoting probiotic organisms, this study exemplifies the importance of strain specificity. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Strain-Specific Features of Extracellular Polysaccharides and Their Impact on Lactobacillus plantarum-Host Interactions

PubMed Central

Lee, I-Chiao; Caggianiello, Graziano; van Swam, Iris I.; Taverne, Nico; Meijerink, Marjolein; Bron, Peter A.; Spano, Giuseppe

2016-01-01

ABSTRACT Lactobacilli are found in diverse environments and are widely applied as probiotic, health-promoting food supplements. Polysaccharides are ubiquitously present on the cell surface of lactobacilli and are considered to contribute to the species- and strain-specific probiotic effects that are typically observed. Two Lactobacillus plantarum strains, SF2A35B and Lp90, have an obvious ropy phenotype, implying high extracellular polysaccharide (EPS) production levels. In this work, we set out to identify the genes involved in EPS production in these L. plantarum strains and to demonstrate their role in EPS production by gene deletion analysis. A model L. plantarum strain, WCFS1, and its previously constructed derivative that produced reduced levels of EPS were included as reference strains. The constructed EPS-reduced derivatives were analyzed for the abundance and sugar compositions of their EPS, revealing cps2-like gene clusters in SF2A35B and Lp90 responsible for major EPS production. Moreover, these mutant strains were tested for phenotypic characteristics that are of relevance for their capacity to interact with the host epithelium in the intestinal tract, including bacterial surface properties as well as survival under the stress conditions encountered in the gastrointestinal tract (acid and bile stress). In addition, the Toll-like receptor 2 (TLR2) signaling and immunomodulatory capacities of the EPS-negative derivatives and their respective wild-type strains were compared, revealing strain-specific impacts of EPS on the immunomodulatory properties. Taken together, these experiments illustrate the importance of EPS in L. plantarum strains as a strain-specific determinant in host interaction. IMPORTANCE This study evaluates the role of extracellular polysaccharides that are produced by different strains of Lactobacillus plantarum in the determination of the cell surface properties of these bacteria and their capacity to interact with their environment, including their signaling to human host cells. The results clearly show that the consequences of removal of these polysaccharides are very strain specific, illustrating the diverse and unpredictable roles of these polysaccharides in the environmental interactions of these bacterial strains. In the context of the use of lactobacilli as health-promoting probiotic organisms, this study exemplifies the importance of strain specificity. PMID:27107126

Morphological Heterogeneity and Attachment of Phaeobacter inhibens.

PubMed

Segev, Einat; Tellez, Adèle; Vlamakis, Hera; Kolter, Roberto

2015-01-01

The Roseobacter clade is a key group of bacteria in the ocean exhibiting diverse metabolic repertoires and a wide range of symbiotic life-styles. Many Roseobacters possess remarkable capabilities of attachment to both biotic and abiotic surfaces. When attached to each other, these bacteria form multi-cellular structures called rosettes. Phaeobacter inhibens, a well-studied Roseobacter, exhibits various cell sizes and morphologies that are either associated with rosettes or occur as single cells. Here we describe the distribution of P. inhibens morphologies and rosettes within a population. We detect an N-acetylglucosamine-containing polysaccharide on the poles of some cells and at the center of all rosettes. We demonstrate that rosettes are formed by the attachment of individual cells at the polysaccharide-containing pole rather than by cell division. Finally, we show that P. inhibens attachment to abiotic surfaces is hindered by the presence of DNA from itself, but not from other bacteria. Taken together, our findings demonstrate that cell adhesiveness is likely to play a significant role in the life cycle of P. inhibens as well as other Roseobacters.

Morphological Heterogeneity and Attachment of Phaeobacter inhibens

PubMed Central

Segev, Einat; Tellez, Adèle; Vlamakis, Hera; Kolter, Roberto

2015-01-01

The Roseobacter clade is a key group of bacteria in the ocean exhibiting diverse metabolic repertoires and a wide range of symbiotic life-styles. Many Roseobacters possess remarkable capabilities of attachment to both biotic and abiotic surfaces. When attached to each other, these bacteria form multi-cellular structures called rosettes. Phaeobacter inhibens, a well-studied Roseobacter, exhibits various cell sizes and morphologies that are either associated with rosettes or occur as single cells. Here we describe the distribution of P. inhibens morphologies and rosettes within a population. We detect an N-acetylglucosamine-containing polysaccharide on the poles of some cells and at the center of all rosettes. We demonstrate that rosettes are formed by the attachment of individual cells at the polysaccharide-containing pole rather than by cell division. Finally, we show that P. inhibens attachment to abiotic surfaces is hindered by the presence of DNA from itself, but not from other bacteria. Taken together, our findings demonstrate that cell adhesiveness is likely to play a significant role in the life cycle of P. inhibens as well as other Roseobacters. PMID:26560130

Surfaceome and Proteosurfaceome in Parietal Monoderm Bacteria: Focus on Protein Cell-Surface Display

PubMed Central

Desvaux, Mickaël; Candela, Thomas; Serror, Pascale

2018-01-01

The cell envelope of parietal monoderm bacteria (archetypal Gram-positive bacteria) is formed of a cytoplasmic membrane (CM) and a cell wall (CW). While the CM is composed of phospholipids, the CW is composed at least of peptidoglycan (PG) covalently linked to other biopolymers, such as teichoic acids, polysaccharides, and/or polyglutamate. Considering the CW is a porous structure with low selective permeability contrary to the CM, the bacterial cell surface hugs the molecular figure of the CW components as a well of the external side of the CM. While the surfaceome corresponds to the totality of the molecules found at the bacterial cell surface, the proteinaceous complement of the surfaceome is the proteosurfaceome. Once translocated across the CM, secreted proteins can either be released in the extracellular milieu or exposed at the cell surface by associating to the CM or the CW. Following the gene ontology (GO) for cellular components, cell-surface proteins at the CM can either be integral (GO: 0031226), i.e., the integral membrane proteins, or anchored to the membrane (GO: 0046658), i.e., the lipoproteins. At the CW (GO: 0009275), cell-surface proteins can be covalently bound, i.e., the LPXTG-proteins, or bound through weak interactions to the PG or wall polysaccharides, i.e., the cell wall binding proteins. Besides monopolypeptides, some proteins can associate to each other to form supramolecular protein structures of high molecular weight, namely the S-layer, pili, flagella, and cellulosomes. After reviewing the cell envelope components and the different molecular mechanisms involved in protein attachment to the cell envelope, perspectives in investigating the proteosurfaceome in parietal monoderm bacteria are further discussed. PMID:29491848

The Potential of Brittle Star Extracted Polysaccharide in Promoting Apoptosis via Intrinsic Signaling Pathway.

PubMed

Baharara, Javad; Amini, Elaheh

2015-01-01

Anti-cancer potential of marine natural products such as polysaccharides represented therapeutic potential in oncological researches. In this study, total polysaccharide from brittle star [Ophiocoma erinaceus (O. erinaceus)] was extracted and chemopreventive efficacy of Persian Gulf brittle star polysaccharide was investigated in HeLa human cervical cancer cells. To extract polysaccharide, dried brittle stars were ground and extracted mechanically. Then, detection of polysaccharide was performed by phenol sulfuric acid, Ultra Violet (UV)-sulfuric acid method and FTIR. The anti proliferative activity of isolated polysaccharide was examined by MTT assay and evaluation of cell death was done through morphological cell changes; Propodium Iodide staining, fluorescence microscopy and caspase-3, -9 enzymatic measurements. To assess its underlying mechanism, expression of Bax, Bcl-2 was evaluated. The polysaccharide detection methods demonstrated isolation of crude polysaccharide from Persian Gulf brittle star. The results revealed that O. erinaceus polysaccharide suppressed the proliferation of HeLa cells in a dose and time dependent manner. Morphological observation of DAPI and Acridine Orange/Propodium Iodide staining was documented by typical characteristics of apoptotic cell death. Flow cytometry analyses exhibited the accumulation of treated cells in sub-G1 region. Additionally, polysaccharide extracted induced intrinsic apoptosis via up-regulation of caspase-3, caspase-9 and Bax along with down-regulation of Bcl-2 in HeLa cells. Taken together, the apoptosis inducing effect of brittle star polysaccharide via intrinsic pathway confirmed the anti tumor potential of marine polysaccharide. Therefore, these findings proposed new insight into anti cancer properties of brittle star polysaccharide as a promising agent in cervical cancer treatment.

Probing the influence of cell surface polysaccharides on nanodendrimer binding to Gram-negative and Gram-positive bacteria using single-nanoparticle force spectroscopy.

PubMed

Beaussart, Audrey; Beloin, Christophe; Ghigo, Jean-Marc; Chapot-Chartier, Marie-Pierre; Kulakauskas, Saulius; Duval, Jérôme F L

2018-06-27

The safe use and design of nanoparticles (NPs) ask for a comprehensive interpretation of their potentially adverse effects on (micro)organisms. In this respect, the prior assessment of the interactions experienced by NPs in the vicinity of - and in contact with - complex biological surfaces is mandatory. It requires the development of suitable techniques for deciphering the processes that govern nano-bio interactions when a single organism is exposed to an extremely low dose of NPs. Here, we used atomic force spectroscopy (AFM)-based force measurements to investigate at the nanoscale the interactions between carboxylate-terminated polyamidoamine (PAMAM) nanodendrimers (radius ca. 4.5 nm) and two bacteria with very distinct surface properties, Escherichia coli and Lactococcus lactis. The zwitterionic nanodendrimers exhibit a negative peripheral surface charge and/or a positive intraparticulate core depending on the solution pH and salt concentration. Following an original strategy according to which a single dendrimer NP is grafted at the very apex of the AFM tip, the density and localization of NP binding sites are probed at the surface of E. coli and L. lactis mutants expressing different cell surface structures (presence/absence of the O-antigen of the lipopolysaccharides (LPS) or of a polysaccharide pellicle). In line with electrokinetic analysis, AFM force measurements evidence that adhesion of NPs onto pellicle-decorated L. lactis is governed by their underlying electrostatic interactions as controlled by the pH-dependent charge of the peripheral and internal NP components, and the negatively-charged cell surface. In contrast, the presence of the O-antigen on E. coli systematically suppresses the adhesion of nanodendrimers onto cells, may the apparent NP surface charge be determined by the peripheral carboxylate groups or by the internal amine functions. Altogether, this work highlights the differentiated roles played by surface polysaccharides in mediating NP attachment to Gram-positive and Gram-negative bacteria. It further demonstrates that the assessment of NP bioadhesion features requires a critical analysis of the electrostatic contributions stemming from the various structures composing the stratified cell envelope, and those originating from the bulk and surface NP components. The joint use of electrokinetics and AFM provides a valuable option for rapidly addressing the binding propensity of NPs to microorganisms, as urgently needed in NP risk assessments.

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 nature of the limiting carbohydrate in continuous culture, varying over a 10-fold range, whereas the cell wall H-polysaccharide remained constant.

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 nature of the limiting carbohydrate in continuous culture, varying over a 10-fold range, whereas the cell wall H-polysaccharide remained constant. PMID:6401290

Solanum Nigrum polysaccharide (SNL) extract effects in transplanted tumor-bearing mice--erythrocyte membrane fluidity and blocking of functions.

PubMed

Yuan, Hong-Liang; Liu, Xiao-Lei; Liu, Ying-Jie

2014-01-01

Solanum nigrum L. has been used in traditional Chinese medicine because of its diuretic and antipyretic effects. The present research concerned effects of crude polysaccharides isolated from Solanum nigrum L. on erythrocyte membranes of tumor-bearing S180 and H22 in mice. Fluorescence- labeled red blood cell membranes were used with DPH fluorescence spectrophotometry to examine erythrocyte membrane fluidity, and colorimetry to determine degree of erythrocyte surface membrane blocking. Extent of reaction by tumor-bearing mice with the enzyme erythrocyte membrane bubble shadow detection of red cell membrane variation in the degree of closure before and after administration. Solanum nigrum polysaccharide could significantly improve the S180 and H22 tumor-bearing mice erythrocyte membrane fluidity, compared with the control group, the difference was significant (p<0.01), SNL can significantly improve the red blood cell membrane and then S180 tumor-bearing mice sealing ability, compared with the negative control group, the difference was significant(p<0.05, p<0.01). H22 tumor-bearing mice can increase red cell membrane and then sealing ability, the difference was significant (p<0.05). Solanum nigrum polysaccharide degree of fluidity and blocking two transplanted tumors in mice restored the ability to raise the red cell membrane has a significant effect. Solanum nigrum L.-type mice transplanted tumor can affect the red blood cell membrane fluidity and re-closed, through the red cell membrane of red blood cells to enhance the immune function of the possibility of erythrocyte immunity against tumor formation garland provide experimental basis.

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.

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.

Characterization of pectic polysaccharides extracted from apple pomace by hot-compressed water.

PubMed

Wang, Xin; Lü, Xin

2014-02-15

Response surface methodology (RSM) was used to optimize the extraction of pectic polysaccharides from apple pomace by hot-compressed water, by which the optimum levels of the parameters were obtained as follows: extraction temperature 140 °C, extraction time 5 min, S:W ratio 1:14. Compared with commercial pectin, the Mw, galacturonic acid content, DM and protein of the extracted pectic polysaccharides were lower while ash content and neutral sugars were higher. The endothermic transition temperature and fusion heat of the extracted pectic polysaccharides was lower than commercial one according to DSC analysis. For its rheological properties, it was found that the viscosity of the extracted pectic polysaccharides solution was slightly lower than commercial pectin at lower shear rate region while it decreased sharply when the shear rate increased. Besides, both G' and G" moduli of the extracted pectic polysaccharides were lower than the commercial pectin's possibly because of weaker polymer chain interaction, which was also reflected in gel textural properties. However, the extracted pectic polysaccharides showed higher in vitro antioxidant capability and inhibitory effect on HT-29 colon adenocarcinoma cells than commercial pectin. Copyright © 2013 Elsevier Ltd. All rights reserved.

Surface decoration by Spirulina polysaccharide enhances the cellular uptake and anticancer efficacy of selenium nanoparticles.

PubMed

Yang, Fang; Tang, Quanming; Zhong, Xueyun; Bai, Yan; Chen, Tianfeng; Zhang, Yibo; Li, Yinghua; Zheng, Wenjie

2012-01-01

A simple and solution-phase method for functionalization of selenium nanoparticles (SeNPs) with Spirulina polysaccharides (SPS) has been developed in the present study. The cellular uptake and anticancer activity of SPS-SeNPs were also evaluated. Monodisperse and homogeneous spherical SPS-SeNPs with diameters ranging from 20 nm to 50 nm were achieved under optimized conditions, which were stable in the solution phase for at least 3 months. SPS surface decoration significantly enhanced the cellular uptake and cytotoxicity of SeNPs toward several human cancer cell lines. A375 human melanoma cells were found extremely susceptible to SPS-SeNPs with half maximal (50%) inhibitory concentration value of 7.94 μM. Investigation of the underlying mechanisms revealed that SPS-SeNPs inhibited cancer cell growth through induction of apoptosis, as evidenced by an increase in sub-G(1) cell population, deoxyribonucleic acid fragmentation, chromatin condensation, and phosphatidylserine translocation. Results suggest that the strategy to use SPS as a surface decorator could be an effective way to enhance the cellular uptake and anticancer efficacy of nanomaterials. SPS-SeNPs may be a potential candidate for further evaluation as a chemopreventive and chemotherapeutic agent against human cancers.

Surface decoration by Spirulina polysaccharide enhances the cellular uptake and anticancer efficacy of selenium nanoparticles

PubMed Central

Yang, Fang; Tang, Quanming; Zhong, Xueyun; Bai, Yan; Chen, Tianfeng; Zhang, Yibo; Li, Yinghua; Zheng, Wenjie

2012-01-01

A simple and solution-phase method for functionalization of selenium nanoparticles (SeNPs) with Spirulina polysaccharides (SPS) has been developed in the present study. The cellular uptake and anticancer activity of SPS-SeNPs were also evaluated. Monodisperse and homogeneous spherical SPS-SeNPs with diameters ranging from 20 nm to 50 nm were achieved under optimized conditions, which were stable in the solution phase for at least 3 months. SPS surface decoration significantly enhanced the cellular uptake and cytotoxicity of SeNPs toward several human cancer cell lines. A375 human melanoma cells were found extremely susceptible to SPS-SeNPs with half maximal (50%) inhibitory concentration value of 7.94 μM. Investigation of the underlying mechanisms revealed that SPS-SeNPs inhibited cancer cell growth through induction of apoptosis, as evidenced by an increase in sub-G1 cell population, deoxyribonucleic acid fragmentation, chromatin condensation, and phosphatidylserine translocation. Results suggest that the strategy to use SPS as a surface decorator could be an effective way to enhance the cellular uptake and anticancer efficacy of nanomaterials. SPS-SeNPs may be a potential candidate for further evaluation as a chemopreventive and chemotherapeutic agent against human cancers. PMID:22359460

Crystal structure of bacterial cell-surface alginate-binding protein with an M75 peptidase motif

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

Maruyama, Yukie; Ochiai, Akihito; Mikami, Bunzo

Research highlights: {yields} Bacterial alginate-binding Algp7 is similar to component EfeO of Fe{sup 2+} transporter. {yields} We determined the crystal structure of Algp7 with a metal-binding motif. {yields} Algp7 consists of two helical bundles formed through duplication of a single bundle. {yields} A deep cleft involved in alginate binding locates around the metal-binding site. {yields} Algp7 may function as a Fe{sup 2+}-chelated alginate-binding protein. -- Abstract: A gram-negative Sphingomonas sp. A1 directly incorporates alginate polysaccharide into the cytoplasm via the cell-surface pit and ABC transporter. A cell-surface alginate-binding protein, Algp7, functions as a concentrator of the polysaccharide in the pit.more » Based on the primary structure and genetic organization in the bacterial genome, Algp7 was found to be homologous to an M75 peptidase motif-containing EfeO, a component of a ferrous ion transporter. Despite the presence of an M75 peptidase motif with high similarity, the Algp7 protein purified from recombinant Escherichia coli cells was inert on insulin B chain and N-benzoyl-Phe-Val-Arg-p-nitroanilide, both of which are substrates for a typical M75 peptidase, imelysin, from Pseudomonas aeruginosa. The X-ray crystallographic structure of Algp7 was determined at 2.10 A resolution by single-wavelength anomalous diffraction. Although a metal-binding motif, HxxE, conserved in zinc ion-dependent M75 peptidases is also found in Algp7, the crystal structure of Algp7 contains no metal even at the motif. The protein consists of two structurally similar up-and-down helical bundles as the basic scaffold. A deep cleft between the bundles is sufficiently large to accommodate macromolecules such as alginate polysaccharide. This is the first structural report on a bacterial cell-surface alginate-binding protein with an M75 peptidase motif.« less

Potential targets for next generation antimicrobial glycoconjugate vaccines

PubMed Central

Micoli, Francesca; Costantino, Paolo; Adamo, Roberto

2018-01-01

Abstract Cell surface carbohydrates have been proven optimal targets for vaccine development. Conjugation of polysaccharides to a carrier protein triggers a T-cell-dependent immune response to the glycan moiety. Licensed glycoconjugate vaccines are produced by chemical conjugation of capsular polysaccharides to prevent meningitis caused by meningococcus, pneumococcus and Haemophilus influenzae type b. However, other classes of carbohydrates (O-antigens, exopolysaccharides, wall/teichoic acids) represent attractive targets for developing vaccines. Recent analysis from WHO/CHO underpins alarming concern toward antibiotic-resistant bacteria, such as the so called ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.) and additional pathogens such as Clostridium difficile and Group A Streptococcus. Fungal infections are also becoming increasingly invasive for immunocompromised patients or hospitalized individuals. Other emergencies could derive from bacteria which spread during environmental calamities (Vibrio cholerae) or with potential as bioterrorism weapons (Burkholderia pseudomallei and mallei, Francisella tularensis). Vaccination could aid reducing the use of broad-spectrum antibiotics and provide protection by herd immunity also to individuals who are not vaccinated. This review analyzes structural and functional differences of the polysaccharides exposed on the surface of emerging pathogenic bacteria, combined with medical need and technological feasibility of corresponding glycoconjugate vaccines. PMID:29547971

Bacterial supersystem for alginate import/metabolism and its environmental and bioenergy applications.

PubMed

Hashimoto, Wataru; Kawai, Shigeyuki; Murata, Kousaku

2010-01-01

Distinct from most alginate-assimilating bacteria that secrete polysaccharide lyases extracellularly, a gram-negative bacterium, Sphingomonas sp. A1 (strain A1), can directly incorporate alginate into its cytoplasm, without degradation, through a "superchannel" consisting of a mouth-like pit on the cell surface, periplasmic binding proteins, and a cytoplasmic membrane-bound ATP-binding cassette transporter. Flagellin homologues function as cell surface alginate receptors essential for expressing the superchannel. Cytoplasmic alginate lyases with different substrate specificities and action modes degrade the polysaccharide to its constituent monosaccharides. The resultant monosaccharides, α-keto acids, are converted to a reduced form by NADPH-dependent reductase, and are finally metabolized in the TCA cycle. Transplantation of the strain A1 superchannel to xenobiotic-degrading sphingomonads enhances bioremediation through the propagation of bacteria with an elevated transport activity. Furthermore, strain A1 cells transformed with Zymomonas mobilis genes for pyruvate decarboxylase and alcohol dehydrogenase II produce considerable amounts of biofuel ethanol from alginate when grown statically. © 2010 Landes Bioscience

Bacterial lipopolysaccharide binding enhances virion stability and promotes environmental fitness of an enteric virus

PubMed Central

Robinson, Christopher M.; Jesudhasan, Palmy R.; Pfeiffer, Julie K.

2014-01-01

Summary Enteric viruses, including poliovirus and reovirus, encounter a vast microbial community in the mammalian gastrointestinal tract, which has been shown to promote virus replication and pathogenesis. Investigating the underlying mechanisms, we find that poliovirus binds bacterial surface polysaccharides, which enhances virion stability and cell attachment by increasing binding to the viral receptor. Additionally, we identified a poliovirus mutant, VP1-T99K, with reduced lipopolysaccharide (LPS) binding. Although T99K and WT poliovirus cell attachment, replication and pathogenesis in mice are equivalent, following peroral inoculation of mice, VP1-T99K poliovirus was unstable in feces. Consequently, the ratio of mutant virus in feces is reduced following additional cycles of infection in mice. Thus, the mutant virus incurs a fitness cost when environmental stability is a factor. These data suggest that poliovirus binds bacterial surface polysaccharides, enhancing cell attachment and environmental stability, potentially promoting transmission to a new host. PMID:24439896

Modulating surface rheology by electrostatic protein/polysaccharide interactions.

PubMed

Ganzevles, Renate A; Zinoviadou, Kyriaki; van Vliet, Ton; Cohen, Martien A; de Jongh, Harmen H

2006-11-21

There is a large interest in mixed protein/polysaccharide layers at air-water and oil-water interfaces because of their ability to stabilize foams and emulsions. Mixed protein/polysaccharide adsorbed layers at air-water interfaces can be prepared either by adsorption of soluble protein/polysaccharide complexes or by sequential adsorption of complexes or polysaccharides to a previously formed protein layer. Even though the final protein and polysaccharide bulk concentrations are the same, the behavior of the adsorbed layers can be very different, depending on the method of preparation. The surface shear modulus of a sequentially formed beta-lactoglobulin/pectin layer can be up to a factor of 6 higher than that of a layer made by simultaneous adsorption. Furthermore, the surface dilatational modulus and surface shear modulus strongly (up to factors of 2 and 7, respectively) depend on the bulk -lactoglobulin/pectin mixing ratio. On the basis of the surface rheological behavior, a mechanistic understanding of how the structure of the adsorbed layers depends on the protein/polysaccharide interaction in bulk solution, mixing ratio, ionic strength, and order of adsorption to the interface (simultaneous or sequential) is derived. Insight into the effect of protein/polysaccharide interactions on the properties of adsorbed layers provides a solid basis to modulate surface rheological behavior.

Protective effect of Dendrobium officinale polysaccharides on H2O2-induced injury in H9c2 cardiomyocytes.

PubMed

Zhao, Xiaoyan; Dou, Mengmeng; Zhang, Zhihao; Zhang, Duoduo; Huang, Chengzhi

2017-10-01

The preliminary studies have shown that Dendrobium officinale possessed therapeutic effects on hypertension and atherosclerosis. Studies also reported that Dendrobium officinale polysaccharides showed antioxidant capabilities. However, little is known about its effects on myocardial cells under oxidative stress. The present study was designed to study the protective effect of Dendrobium officinale polysaccharides against H 2 O 2 -induced oxidative stress in H9c2 cells. MTT assay was carried out to determine the cell viability of H9c2 cells when pretreated with Dendrobium officinale polysaccharides. Fluorescent microscopy measurements were performed for evaluating the apoptosis in H9c2 cells. Furthermore, effects of Dendrobium officinale polysaccharides on the activities of antioxidative indicators (malondialdehyde, superoxide dismutase), reactive oxygen species (ROS) production and mitochondrial membrane potential (MMP) levels were analyzed. Dendrobium officinale polysaccharides attenuated H 2 O 2 -induced cell death, as determined by the MTT assay. Dendrobium officinale polysaccharides decreased malondialdehyde levels, increased superoxide dismutase activities, and inhibited the generation of intracellular ROS. Moreover, pretreatment with Dendrobium officinale polysaccharides also inhibited apoptosis and increased the MMP levels in H9c2 cells. These results suggested the protective effects of Dendrobium officinale polysaccharides against H 2 O 2 -induced injury in H9c2 cells. The results also indicated the anti-oxidative capability of Dendrobium officinale polysaccharides. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Comparison of antioxidant and antiproliferation activities of polysaccharides from eight species of medicinal mushrooms.

PubMed

Chen, Peiying; Yong, Yangyang; Gu, Yifan; Wang, Zeliang; Zhang, Shizhu; Lu, Ling

2015-01-01

Polysaccharides from mushrooms including Pleurotus eryngii, P. ostreatus, P. nebrodensis, Lentinus edodes, Hypsizygus marmoreus, Flammulina velutipes, Ganoderma lucidum, and Hericium erinaceus were isolated by water extraction and alcohol precipitation. Our results suggest that all tested polysaccharides have the significant antioxidant capacities of scavenging free radicals (1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals). Among them, the H. erinaceus polysaccharide exhibits the highest 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity, whereas the L. edodes polysaccharide shows the strongest scavenging ability for hydroxyl radicals. Furthermore, using the MCF-7 breast cancer cell line and HeLa cells, all 8 selected polysaccharides are able to inhibit the proliferation of tumor cells, but the strength of inhibition varied depending on the mushroom species and the concentration used. Notably, G. lucidum polysaccharide shows the highest inhibition activity on MCF-7 cells. By comparison, H. erinaceus polysaccharide has the strongest inhibitory effect on HeLa cells. Moreover, high-performance liquid chromatography with a carbohydrate analysis column showed significant differences in polysaccharide components among these mushrooms. Thus our data suggest that the different species of mushrooms have the variable functions because of their own specific polysaccharide components. The 8 mushroom polysaccharides have the potential to be used as valuable functional food additives or sources of therapeutic agents for antioxidant and cancer treatments, especially polysaccharides from H. erinaceus, L. edodes, and G. lucidum.

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.

Identification, structure, and characterization of an exopolysaccharide produced by Histophilus somni during biofilm formation.

PubMed

Sandal, Indra; Inzana, Thomas J; Molinaro, Antonio; De Castro, Christina; Shao, Jian Q; Apicella, Michael A; Cox, Andrew D; St Michael, Frank; Berg, Gretchen

2011-08-19

Histophilus somni, a gram-negative coccobacillus, is an obligate inhabitant of bovine and ovine mucosal surfaces, and an opportunistic pathogen responsible for respiratory disease and other systemic infections in cattle and sheep. Capsules are important virulence factors for many pathogenic bacteria, but a capsule has not been identified on H. somni. However, H. somni does form a biofilm in vitro and in vivo, and the biofilm matrix of most bacteria consists of a polysaccharide. Following incubation of H. somni under growth-restricting stress conditions, such as during anaerobiosis, stationary phase, or in hypertonic salt, a polysaccharide could be isolated from washed cells or culture supernatant. The polysaccharide was present in large amounts in broth culture sediment after H. somni was grown under low oxygen tension for 4-5 days (conditions favorable to biofilm formation), but not from planktonic cells during log phase growth. Immuno-transmission electron microscopy showed that the polysaccharide was not closely associated with the cell surface, and was of heterogeneous high molecular size by gel electrophoresis, indicating it was an exopolysaccharide (EPS). The EPS was a branched mannose polymer containing some galactose, as determined by structural analysis. The mannose-specific Moringa M lectin and antibodies to the EPS bound to the biofilm matrix, demonstrating that the EPS was a component of the biofilm. The addition of N-acetylneuraminic acid to the growth medium resulted in sialylation of the EPS, and increased biofilm formation. Real-time quantitative reverse transcription-polymerase chain reaction analyses indicated that genes previously identified in a putative polysaccharide locus were upregulated when the bacteria were grown under conditions favorable to a biofilm, compared to planktonic cells. H. somni is capable of producing a branching, mannose-galactose EPS polymer under growth conditions favorable to the biofilm phase of growth, and the EPS is a component of the biofilm matrix. The EPS can be sialylated in strains with sialyltransferase activity, resulting in enhanced density of the biofilm, and suggesting that EPS and biofilm formation may be important to persistence in the bovine host. The EPS may be critical to virulence if the biofilm state is required for H. somni to persist in systemic sites.

Bacterial surface adaptation

NASA Astrophysics Data System (ADS)

Utada, Andrew

2014-03-01

Biofilms are structured multi-cellular communities that are fundamental to the biology and ecology of bacteria. Parasitic bacterial biofilms can cause lethal infections and biofouling, but commensal bacterial biofilms, such as those found in the gut, can break down otherwise indigestible plant polysaccharides and allow us to enjoy vegetables. The first step in biofilm formation, adaptation to life on a surface, requires a working knowledge of low Reynolds number fluid physics, and the coordination of biochemical signaling, polysaccharide production, and molecular motility motors. These crucial early stages of biofilm formation are at present poorly understood. By adapting methods from soft matter physics, we dissect bacterial social behavior at the single cell level for several prototypical bacterial species, including Pseudomonas aeruginosa and Vibrio cholerae.

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.

A Polysaccharide Isolated from Mycelia of the Lion's Mane Medicinal Mushroom Hericium erinaceus (Agaricomycetes) Induced Apoptosis in Precancerous Human Gastric Cells.

PubMed

Wang, Mingxing; Zhang, Yanqiu; Xiao, Xulang; Xu, Duoduo; Gao, Yang; Gao, Qipin

2017-01-01

Hericium erinaceus is typically used in traditional Chinese medicine for mucosal protection, healing of gastric ulcers, and treatment of gastritis. We purified from the cultured mycelia of H. erinaceus a polysaccharide with anti-gastric ulcer and antigastritis activity, but its effects on gastric malignancy have not been elucidated. We examined the differential effects of this purified polysaccharide, named EP-1, on the human gastric (GES-1) cell line and a precancerous cell line (MC) that was transformed from GES-1 using N-methyl-N'-nitro-N-nitrosoguanidine. We observed that the polysaccharide potently induced cell apoptosis and cell cycle arrest at the G0/G1 phase in the MC cell line but did not have any effect on the GES-1 cell line at the same doses. Further mechanistic studies revealed that the polysaccharide exerted its activity through an apoptosis-associated pathway by modulating the expression of Bax, Bcl-2, and caspase-3. Differential effects of the polysaccharide on the GES-1 and MC cell lines indicate that the polysaccharide was effective in preventing gastric cancer progression.

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.

Spatial Periodicity of Escherichia coli K-12 Biofilm Microstructure Initiates during a Reversible, Polar Attachment Phase of Development and Requires the Polysaccharide Adhesin PGA

PubMed Central

Agladze, Konstantin; Wang, Xin; Romeo, Tony

2005-01-01

Using fast Fourier transform (FFT) analysis, we previously observed that cells within Escherichia coli biofilm are organized in nonrandom or periodic spatial patterns (K. Agladze et al., J. Bacteriol. 185:5632-5638, 2003). Here, we developed a gravity displacement assay for examining cell adherence and used it to quantitatively monitor the formation of two distinct forms of cell attachment, temporary and permanent, during early biofilm development. Temporarily attached cells were mainly surface associated by a cell pole; permanent attachments were via the lateral cell surface. While temporary attachment precedes permanent attachment, both forms can coexist in a population. Exposure of attached cells to gravity liberated an unattached population capable of rapidly reassembling a new monolayer, composed of temporarily attached cells, and possessing periodicity. A csrA mutant, which forms biofilm more vigorously than its wild-type parent, exhibited an increased proportion of permanently attached cells and a form of attachment that was not apparent in the parent strain, permanent polar attachment. Nevertheless, it formed periodic attachment patterns. In contrast, biofilm mutants with altered lipopolysaccharide synthesis (waaG) exhibited increased cell-cell interactions, bypassed the polar attachment step, and produced FFT spectra characteristic of aperiodic cell distribution. Mutants lacking the polysaccharide adhesin β-1,6-N-acetyl-d-glucosamine (ΔpgaC) also exhibited aperiodic cell distribution, but without apparent cell-cell interactions, and were defective in forming permanent attachments. Thus, spatial periodicity of biofilm microstructure is genetically determined and evident during the formation of temporary cell surface attachments. PMID:16321928

Changes in polysaccharide and protein composition of cell walls in grape berry skin (Cv. Shiraz) during ripening and over-ripening.

PubMed

Vicens, Anysia; Fournand, David; Williams, Pascale; Sidhoum, Louise; Moutounet, Michel; Doco, Thierry

2009-04-08

Polysaccharide modification is the most fundamental factor that affects firmness of fruit during ripening. In grape, because of the lack of information on the modifications occurring in cell wall polysaccharides in skins, but also because this tissue contains large amounts of organoleptic compounds for winemaking, a study was performed on the evolution and extractability of polysaccharides from grape skins of Shiraz cultivar throughout ripening. A HEPES/phenol extraction technique was used to analyze Shiraz grape cell wall material isolated from skins of berries harvested from one to ten weeks after veraison. Total amounts in cell wall polysaccharides remained constant during ripening (4.2 mg/berry). A slight decrease in galactose content of insoluble polysaccharides was observed, as well as a significant de-esterification of methoxylated uronic acids, indicating that some modifications occur in cell wall polysaccharides. The water-soluble fraction represented a very small fraction of the whole polysaccharides, but its amounts increased more than 2-fold between the first and the last sample. Isolated cell walls were also analyzed for their protein composition. Last, hydroalcoholic extractions in model-wine solution were also performed on fresh skins. This extracted fraction was very similar to the water-soluble one, and increased during the entire period. By comparison with polysaccharide modifications described in flesh cell wall in previous works, it can be assumed that the moderate skin polysaccharide degradation highlights the protective role of that tissue.

Activation of intrinsic apoptotic signaling pathway in cancer cells by Cymbopogon citratus polysaccharide fractions.

PubMed

Thangam, Ramar; Sathuvan, Malairaj; Poongodi, Arasu; Suresh, Veeraperumal; Pazhanichamy, Kalailingam; Sivasubramanian, Srinivasan; Kanipandian, Nagarajan; Ganesan, Nalini; Rengasamy, Ramasamy; Thirumurugan, Ramasamy; Kannan, Soundarapandian

2014-07-17

Essential oils of Cymbopogon citratus were already reported to have wide ranging medical and industrial applications. However, information on polysaccharides from the plant and their anticancer activities are limited. In the present study, polysaccharides from C. citratus were extracted and fractionated by anion exchange and gel filtration chromatography. Two different polysaccharide fractions such as F1 and F2 were obtained, and these fractions were found to have distinct acidic polysaccharides as characterized by their molecular weight and sugar content. NMR spectral analysis revealed the presence of (1→4) linked b-d-Xylofuranose moiety in these polysaccharides. Using these polysaccharide fractions F1 and F2, anti-inflammatory and anticancer activities were evaluated against cancer cells in vitro and the mechanism of action of the polysaccharides in inducing apoptosis in cancer cells via intrinsic pathway was also proposed. Two different reproductive cancer cells such as Siha and LNCap were employed for in vitro studies on cytotoxicity, induction of apoptosis and apoptotic DNA fragmentation, changes in mitochondrial membrane potential, and profiles of gene and protein expression in response to treatment of cells by the polysaccharide fractions. These polysaccharide fractions exhibited potential cytotoxic and apoptotic effects on carcinoma cells, and they induced apoptosis in these cells through the events of up-regulation of caspase 3, down-regulation of bcl-2 family genes followed by cytochrome c release. Copyright © 2014 Elsevier Ltd. All rights reserved.

IMMUNE DIFFUSION ANALYSIS OF THE EXTRACELLULAR SOLUBLE ANTIGENS OF TWO STRAINS OF RHIZOBIUM MELILOTI

PubMed Central

Dudman, W. F.

1964-01-01

Dudman, W. F. (Commonwealth Scientific and Industrial Research Organization, Canberra, Australia). Immune diffusion analysis of the extracellular soluble antigens of two strains of Rhizobium meliloti. J. Bacteriol. 88:782–794. 1964.—Immune diffusion techniques applied to cultures of two strains of Rhizobium meliloti grown in liquid defined medium showed the presence of multiple antigens. Improved resolution of precipitin patterns was obtained with concentrated antigens separated from the cultures as the extracellular soluble fraction or as suspensions of washed cells. The extracellular fraction contained the same diffusible antigens as the washed cells, but additional antigens were found in the cells after ultrasonic disruption. The extracellular soluble antigens were shown by analysis to contain polysaccharide and protein components. In immune diffusion systems, they gave rise to three groups of precipitin bands, two of which were characterized as polysaccharides by their susceptibility to periodate oxidation, and the third as protein by its lability to heat. All the extracellular antigens of both strains were shared except a fast-diffusing polysaccharide, which was specific for each strain. Despite the sharing of all but one of their antigens, cells of these strains showed only a low degree of cross-agglutination, suggesting that their surfaces are dominated by the specific polysaccharide. No differences could be found in the composition of the polysaccharides in the unfractionated extracellular antigens of the two strains, the main components of which were glucose (66%) and galactose (12%) in the presence of several other unidentified sugars in smaller amounts. The pattern of precipitin bands produced in immune diffusion systems by the extracellular soluble fraction could be changed by altering the cultural conditions. Images PMID:14208519

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.

Polysaccharides Isolated from Açaí Fruit Induce Innate Immune Responses

PubMed Central

Holderness, Jeff; Schepetkin, Igor A.; Freedman, Brett; Kirpotina, Liliya N.; Quinn, Mark T.; Hedges, Jodi F.; Jutila, Mark A.

2011-01-01

The Açaí (Acai) fruit is a popular nutritional supplement that purportedly enhances immune system function. These anecdotal claims are supported by limited studies describing immune responses to the Acai polyphenol fraction. Previously, we characterized γδ T cell responses to both polyphenol and polysaccharide fractions from several plant-derived nutritional supplements. Similar polyphenol and polysaccharide fractions are found in Acai fruit. Thus, we hypothesized that one or both of these fractions could activate γδ T cells. Contrary to previous reports, we did not identify agonist activity in the polyphenol fraction; however, the Acai polysaccharide fraction induced robust γδ T cell stimulatory activity in human, mouse, and bovine PBMC cultures. To characterize the immune response to Acai polysaccharides, we fractionated the crude polysaccharide preparation and tested these fractions for activity in human PBMC cultures. The largest Acai polysaccharides were the most active in vitro as indicated by activation of myeloid and γδ T cells. When delivered in vivo, Acai polysaccharide induced myeloid cell recruitment and IL-12 production. These results define innate immune responses induced by the polysaccharide component of Acai and have implications for the treatment of asthma and infectious disease. PMID:21386979

Microwave-assisted extraction of polysaccharides from Cyphomandra betacea and its biological activities.

PubMed

C, Senthil Kumar; M, Sivakumar; K, Ruckmani

2016-11-01

Response Surface Methodology (RSM) was used to optimize the parameters for microwave-assisted extraction of polysaccharides from Cyphomandra betacea. The results showed a good fit with a second-order polynomial equation that was statistically acceptable at P<0.05. Optimal conditions for the extraction of polysaccharides were: extraction time, 2h; microwave power, 400W; extraction temperature, 60°C; and ratio of raw material to water 1:40 (g/mL). Under the optimized conditions, the yield of polysaccharides was found to be relatively high (about 36.52%). The in vitro biological activities of antioxidant and antitumor were evaluated. The IC 50 value of polysaccharides was found to be 3mg/mL. The percentage of Cell viability was determined by MTT assay. Our results showed that polysaccharides inhibited proliferation of MCF-7 (Breast carcinoma), A549 (Human lung carcinoma) and HepG2 (Liver carcinoma) with an IC 50 of 0.23mg/mL, 0.17mg/mL and 0.62mg/mL respectively after 48h incubation. Polysaccharides were shown to promote apoptosis as seen in the nuclear morphological examination study using acridine orange (AO) and ethidium bromide (EB) staining. This is the first report on the effects of polysaccharides extracted from Cyphomandra betacea which exhibited stronger antioxidant and antitumor activities. Copyright © 2016 Elsevier B.V. All rights reserved.

Cytoprotective effect of polysaccharide isolated from different mushrooms against 7-ketocholesterol induced damage in mouse liver cell line (BNL CL. 2).

PubMed

Kim, Joo-Shin; Chung, Hau Yin; Na, Keun

2007-01-01

Cytoprotective ability of polysaccharides isolated from different edible mushrooms was investigated on the 7-ketocholesterol-induced damaged cell line. Polysaccharide extracts from six different edible mushrooms-Flammulina velutipes, Peurotus ostreatus, Lentinus edodes, Agrocybe aegerita, Agaricus blazei, and Cordyceps militaris- were prepared by hot water extraction and alcohol precipitation. Cytoprotective ability was evaluated by measuring the viable cells of the normal embryonic liver cell line (BNL CL. 2) in the presence of 7-ketocholesterol. At 80 microg/mL of 7-ketocholesterol, cytotoxicity was very high with a loss of 98% of viable cells after 20 h of incubation. With the addition of 200 microg/mL of each polysaccharide isolate to the cell line containing 80 microg/mL of 7-ketocholesterol, polysaccharide isolates from both Flammulina velutipes and Peurotus ostreatus could significantly inhibit the 7-ketochoelsterol-induced cytotoxicity in the cells. But other polysaccharide isolates were not effective in inhibiting cell damage caused by the oxLDL-induced cytotoxicity.

Cytoprotective effect of polysaccharide isolated from different mushrooms against 7-ketocholesterol induced damage in mouse liver cell line (BNL CL. 2)

PubMed Central

Chung, Hau Yin; Na, Keun

2007-01-01

Cytoprotective ability of polysaccharides isolated from different edible mushrooms was investigated on the 7-ketocholesterol-induced damaged cell line. Polysaccharide extracts from six different edible mushrooms-Flammulina velutipes, Peurotus ostreatus, Lentinus edodes, Agrocybe aegerita, Agaricus blazei, and Cordyceps militaris- were prepared by hot water extraction and alcohol precipitation. Cytoprotective ability was evaluated by measuring the viable cells of the normal embryonic liver cell line (BNL CL. 2) in the presence of 7-ketocholesterol. At 80 µg/mL of 7-ketocholesterol, cytotoxicity was very high with a loss of 98% of viable cells after 20 h of incubation. With the addition of 200 µg/mL of each polysaccharide isolate to the cell line containing 80 µg/mL of 7-ketocholesterol, polysaccharide isolates from both Flammulina velutipes and Peurotus ostreatus could significantly inhibit the 7-ketochoelsterol-induced cytotoxicity in the cells. But other polysaccharide isolates were not effective in inhibiting cell damage caused by the oxLDL-induced cytotoxicity. PMID:20368935

Structural investigation of cell wall polysaccharides of Lactobacillus delbrueckii subsp. bulgaricus 17.

PubMed

Vinogradov, E; Sadovskaya, I; Cornelissen, A; van Sinderen, D

2015-09-02

Lactobacilli are valuable strains for commercial (functional) food fermentations. Their cell surface-associated polysaccharides (sPSs) possess important functional properties, such as acting as receptors for bacteriophages (bacterial viruses), influencing autolytic characteristics and providing protection against antimicrobial peptides. The current report provides an elaborate molecular description of several surface carbohydrates of Lactobacillus delbrueckii subsp. bulgaricus strain 17. The cell surface of this strain was shown to contain short chain poly(glycerophosphate) teichoic acids and at least two different sPSs, designated here as sPS1 and sPS2, whose chemical structures were examined by 2D nuclear magnetic resonance spectroscopy and methylation analysis. Neutral branched sPS1, extracted with n-butanol, was shown to be composed of hexasaccharide repeating units (-[α-d-Glcp-(1-3)-]-4-β-l-Rhap2OAc-4-β-d-Glcp-[α-d-Galp-(1-3)]-4-α-Rhap-3-α-d-Galp-), while the major component of the TCA-extracted sPS2 was demonstrated to be a linear d-galactan with the repeating unit structure being (-[Gro-3P-(1-6)-]-3-β-Galf-3-α-Galp-2-β-Galf-6-β-Galf-3-β-Galp-). Copyright © 2015 Elsevier Ltd. All rights reserved.

Two Variants of a High-Throughput Fluorescent Microplate Assay of Polysaccharide Endotransglycosylases.

PubMed

Kováčová, Kristína; Farkaš, Vladimír

2016-04-01

Polysaccharide endotransglycosylases (PETs) are the cell wall-modifying enzymes of fungi and plants. They catalyze random endo-splitting of the polysaccharide donor molecule and transfer of the newly formed reducing sugar residue to the nonreducing end of an acceptor molecule which can be a polysaccharide or an oligosaccharide. Owing to their important role in the cell wall formation, the inhibition of PETs represents an attractive strategy in the fight against fungal infections. We have elaborated two variants of a versatile high-throughput microplate fluorimetric assay that could be used for effective identification of PETs and screening of their inhibitors. Both assays use the respective polysaccharides as the donors and sulforhodamine-labeled oligosaccharides as the acceptors but differ from each other by mode of how the labeled polysaccharide products of transglycosylation are separated from the unreacted oligosaccharide acceptors. In the first variant, the reactions take place in a layer of agar gel laid on the bottoms of the wells of a microtitration plate. After the reaction, the high-Mr transglycosylation products are precipitated with 66 % ethanol and retained within the gel while the low-Mr products and the unreacted acceptors are washed out. In the second variant, the donor polysaccharides are adsorbed to the surface of a microplate well and remain adsorbed there also after becoming labeled in the course of the transglycosylation reaction whereas the unused low-Mr acceptors are washed out. As a proof of versatility, assays of heterologously expressed transglycosylases ScGas1, ScCrh1, and ScCrh2 from the yeast Saccharomyces cerevisiae, CaPhr1 and CaPhr2 from Candida albicans, and of a plant xyloglucan endotransglycosylase (XET) are demonstrated.

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

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

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

1991-09-03

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

Inorganic Phosphate Limitation Modulates Capsular Polysaccharide Composition in Mycobacteria.

PubMed

van de Weerd, Robert; Boot, Maikel; Maaskant, Janneke; Sparrius, Marion; Verboom, Theo; van Leeuwen, Lisanne M; Burggraaf, Maroeska J; Paauw, Nanne J; Dainese, Elisa; Manganelli, Riccardo; Bitter, Wilbert; Appelmelk, Ben J; Geurtsen, Jeroen

2016-05-27

Mycobacterium tuberculosis is protected by an unusual and highly impermeable cell envelope that is critically important for the successful colonization of the host. The outermost surface of this cell envelope is formed by capsular polysaccharides that play an important role in modulating the initial interactions once the bacillus enters the body. Although the bioenzymatic steps involved in the production of the capsular polysaccharides are emerging, information regarding the ability of the bacterium to modulate the composition of the capsule is still unknown. Here, we study the mechanisms involved in regulation of mycobacterial capsule biosynthesis using a high throughput screen for gene products involved in capsular α-glucan production. Utilizing this approach we identified a group of mutants that all carried mutations in the ATP-binding cassette phosphate transport locus pst These mutants collectively exhibited a strong overproduction of capsular polysaccharides, including α-glucan and arabinomannan, suggestive of a role for inorganic phosphate (Pi) metabolism in modulating capsular polysaccharide production. These findings were corroborated by the observation that growth under low Pi conditions as well as chemical activation of the stringent response induces capsule production in a number of mycobacterial species. This induction is, in part, dependent on σ factor E. Finally, we show that Mycobacterium marinum, a model organism for M. tuberculosis, encounters Pi stress during infection, which shows the relevance of our findings in vivo. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Extraction of Polysaccharide from Spirulina and Evaluation of Its Activities.

PubMed

Wang, Bingyue; Liu, Qian; Huang, Yinghong; Yuan, Yueling; Ma, Qianqian; Du, Manling; Cai, Tiange; Cai, Yu

2018-01-01

Polysaccharide of Spirulina platensis (PSP) is a kind of water-soluble polysaccharide extracted from Spirulina platensis . It has been proved to have antitumor, antioxidation, antiaging, and antivirus properties. And it has a promising prospect for wide application. This study aims to identify an extraction process for high-purity polysaccharide in Spirulina (PSP) through a series of optimization methods and then evaluates its initial antiaging activities. Four kinds of extraction methods-hot-water extraction, alkali extraction, ultrasonic-assisted extraction, and freeze-thaw extraction-were compared to find the optimal one, which was further optimized by response surface methodology. PSP was obtained after the crude PSP was deproteinized and depigmented. The antiaging effects of PSP were preliminarily evaluated through in vitro cell experiments. The alkali extraction method was determined as the optimal method, with the optimized extraction process consisting of a solid-liquid ratio of 1 : 50, a pH value of 10.25, a temperature of 89.24°C, and a time of 9.99 h. The final PSP contained 71.65% of polysaccharide and 8.54% of protein. At a concentration of 50  μ g/mL, PSP exerted a significant promoting effect on the proliferation and traumatic fusion of human immortalized epidermal cells HaCaT. An extraction method for high-purity PSP with a high extraction rate was established, and in vitro results suggest antioxidation and antiaging activities.

Jellyfish skin polysaccharides: extraction and inhibitory activity on macrophage-derived foam cell formation.

PubMed

Zhang, Hai-Lin; Cui, Shao-Hua; Zha, Xue-Qiang; Bansal, Vibha; Xue, Lei; Li, Xiao-Long; Hao, Ran; Pan, Li-Hua; Luo, Jian-Ping

2014-06-15

In this work, response surface methodology was used to determine optimum conditions for extraction of polysaccharides from jellyfish skin (JSP). The optimum parameters were found to be raw material to water ratio 1:7.5 (w/v), extraction temperature 100°C and extraction time 4h. Under these conditions, the JSP yield reached 1.007 mg/g. Papain (15 U/mL) in combination with Sevag reagent was beneficial in removing proteins from JSP. After precipitation with ethanol at final concentration of 40%, 60% and 80% in turn, three polysaccharide fractions of JSP1, JSP2 and JSP3 were obtained from JSP, respectively. The three fractions exhibited different physicochemical properties with respect to molecular weight distribution, monosaccharide composition, infrared absorption spectra, and glycosyl bond composition. In addition, JSP3 showed strong inhibitory effects on oxidized low-density lipoprotein (oxLDL) induced conversion of macrophages into foam cells, which possibly attributed to the down-regulation of some atherogenesis-related gene expressions. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Stimuli sensitive changes in electrical surface properties of soft membranes: from a synthesized polymer to a biological system].

PubMed

Makino, K

1997-01-01

The electrical surface properties of biological cells have been studied, which provided us with the fundamental knowledge about the cell surface. The change in shape or biological functions of cells may affect the surface properties and can be detected by electrokinetic measurements. Biological cell surfaces are covered with polysaccharide chains, some are charged and some are not. Some polysaccharides produce a hydrogel matrixes under a proper condition. We thus consider it reasonable that cell surface is approximated by a hydrogel surface. Electrophoretic mobility measurements are useful for studying the surface properties of biological cells suspended as colloidal particles in an electrolyte solution. The electro-osmotic velocity measurements on the other hand are advantageous to the study of the surface properties of slab-shaped biological systems such as membranes. This work was started with a hydrogel, as a model material. As a hydrogel, poly(N-isopropylacrylamide) poly(NIPAAm), abbreviated as hereafter, was chosen, because this hydrogel changes its volume depending on temperature. The dependence of the electrophoretic mobility of latex particles covered with poly(NIPAAm) hydrogel layer or of the electro-osmotic mobility on poly(NIPAAm) plate upon temperature and ionic strength of the dispersing medium was well explained with an electrophoretic mobility formula for "soft particles" developed by Ohshima. The electrokinetic measurements and the explanation of data with an electrophoretic mobility formula for "soft particles" give us information about the surface charge density and the "softness" of soft surfaces. On the basis of the findings with hydrogels, we have discussed the relationship between the changes in shape or function of the biological cells and the change in physicochemical surface properties using these measurements. To study the change in physicochemical properties of the cell surface caused by apoptosis, we have measured the electrophoretic mobilities of intact and apoptotic human promyelocytic leukemia cell lines, HL-60RG cells. We have also studied the differences observed in surface properties of malignant lymphosarcoma cell line, RAW117-P, and its variant, RAW117-H10, with a high metastatic property to the liver. In both cases, the cell surfaces became softer by the changes of biological functions. We have applied electrophoresis and electro-osmosis measurements to the study of the electrokinetic surface properties of rat basophilic leukemia cells, RBL cells. It was also found that the surface of Human umbilical vein endothelial cells, HUVEC, is considerably soft as compared with those of other biological cells we have studied before.

ABC Transporters Involved in Export of Cell Surface Glycoconjugates

PubMed Central

Cuthbertson, Leslie; Kos, Veronica; Whitfield, Chris

2010-01-01

Summary: Complex glycoconjugates play critical roles in the biology of microorganisms. Despite the remarkable diversity in glycan structures and the bacteria that produce them, conserved themes are evident in the biosynthesis-export pathways. One of the primary pathways involves representatives of the ATP-binding cassette (ABC) transporter superfamily. These proteins are responsible for the export of a wide variety of cell surface oligo- and polysaccharides in both Gram-positive and Gram-negative bacteria. Recent investigations of the structure and function of ABC transporters involved in the export of lipopolysaccharide O antigens have revealed two fundamentally different strategies for coupling glycan polymerization to export. These mechanisms are distinguished by the presence (or absence) of characteristic nonreducing terminal modifications on the export substrates, which serve as chain termination and/or export signals, and by the presence (or absence) of a discrete substrate-binding domain in the nucleotide-binding domain polypeptide of the ABC transporter. A bioinformatic survey examining ABC exporters from known oligo- and polysaccharide biosynthesis loci identifies conserved nucleotide-binding domain protein families that correlate well with themes in the structures and assembly of glycans. The familial relationships among the ABC exporters generate hypotheses concerning the biosynthesis of structurally diverse oligo- and polysaccharides, which play important roles in the biology of bacteria with different lifestyles. PMID:20805402

Herpes Simplex Virus Type 2 Glycoprotein G Is Targeted by the Sulfated Oligo- and Polysaccharide Inhibitors of Virus Attachment to Cells▿

PubMed Central

Adamiak, Beata; Ekblad, Maria; Bergström, Tomas; Ferro, Vito; Trybala, Edward

2007-01-01

Variants of herpes simplex virus type 2 (HSV-2) generated by virus passage in GMK-AH1 cells in the presence of the sulfated oligosaccharide PI-88 were analyzed. Many of these variants were substantially resistant to PI-88 in their initial infection of cells and/or their cell-to-cell spread. The major alteration detected in all variants resistant to PI-88 in the initial infection of cells was a frameshift mutation(s) in the glycoprotein G (gG) gene that resulted in the lack of protein expression. Molecular transfer of the altered gG gene into the wild-type background confirmed that the gG-deficient recombinants were resistant to PI-88. In addition to PI-88, all gG-deficient variants of HSV-2 were resistant to the sulfated polysaccharide heparin. The gG-deficient virions were capable of attaching to cells, and this activity was relatively resistant to PI-88. In addition to having a drug-resistant phenotype, the gG-deficient variants were inefficiently released from infected cells. Purified gG bound to heparin and showed the cell-binding activity which was inhibited by PI-88. Many PI-88 variants produced syncytia in cultured cells and contained alterations in gB, including the syncytium-inducing L792P amino acid substitution. Although this phenotype can enhance the lateral spread of HSV in cells, it conferred no virus resistance to PI-88. Some PI-88 variants also contained occasional alterations in gC, gD, gE, gK, and UL24. In conclusion, we found that glycoprotein gG, a mucin-like component of the HSV-2 envelope, was targeted by sulfated oligo- and polysaccharides. This is a novel finding that suggests the involvement of HSV-2 gG in interactions with sulfated polysaccharides, including cell surface glycosaminoglycans. PMID:17928351

A glycosylphosphatidylinositol anchor is required for membrane localization but dispensable for cell wall association of chitin deacetylase 2 in Cryptococcus neoformans.

PubMed

Gilbert, Nicole M; Baker, Lorina G; Specht, Charles A; Lodge, Jennifer K

2012-01-01

Cell wall proteins (CWPs) mediate important cellular processes in fungi, including adhesion, invasion, biofilm formation, and flocculation. The current model of fungal cell wall organization includes a major class of CWPs covalently bound to β-1,6-glucan via a remnant of a glycosylphosphatidylinositol (GPI) anchor. This model was established by studies of ascomycetes more than a decade ago, and relatively little work has been done with other fungi, although the presumption has been that proteins identified in the cell wall which contain a predicted GPI anchor are covalently linked to cell wall glucans. The pathogenic basidiomycete Cryptococcus neoformans encodes >50 putatively GPI-anchored proteins, some of which have been identified in the cell wall. One of these proteins is chitin deacetylase 2 (Cda2), an enzyme responsible for converting chitin to chitosan, a cell wall polymer recently established as a virulence factor for C. neoformans infection of mammalian hosts. Using a combination of biochemistry, molecular biology, and genetics, we show that Cda2 is GPI anchored to membranes but noncovalently associated with the cell wall by means independent of both its GPI anchor and β-1,6-glucan. We also show that Cda2 produces chitosan when localized to the plasma membrane, but association with the cell wall is not essential for this process, thereby providing insight into the mechanism of chitosan biosynthesis. These results increase our understanding of the surface of C. neoformans and provide models of cell walls likely applicable to other undercharacterized basidiomycete pathogenic fungi. The surface of a pathogenic microbe is a major interface with its host. In fungi, the outer surface consists of a complex matrix known as the cell wall, which includes polysaccharides, proteins, and other molecules. The mammalian host recognizes many of these surface molecules and mounts appropriate responses to combat the microbial infection. Cryptococcus neoformans is a serious fungal pathogen that kills over 600,000 people annually. It converts most of its chitin, a cell wall polysaccharide, to chitosan, which is necessary for virulence. Chitin deacetylase enzymes have been identified in the cell wall, and our studies were undertaken to understand how the deacetylase is linked to the wall and where it has activity. Our results have implications for the current model of chitosan biosynthesis and further challenge the paradigm of covalent linkages between cell wall proteins and polysaccharides through a lipid modification of the protein.

Flocculation of colloidal clay by bacterial polysaccharides: effect of macromolecule charge and structure.

PubMed

Labille, J; Thomas, F; Milas, M; Vanhaverbeke, C

2005-04-01

The molecular mechanism of montmorillonite flocculation by bacterial polysaccharides was investigated, with special emphasis on the effect of carboxylic charges in the macromolecules on the mechanisms of interaction with the clay surface. An indirect way to quantify the energy of interaction was used, by comparing the flocculation ability of variously acidic polysaccharides. Data on tensile strength of aggregates in diluted suspension were collected by timed size measurements in the domain 0.1-600 microm, using laser diffraction. The flow behavior of settled aggregates was studied by rheology measurements. Flocculation of colloidal clay suspension by polysaccharides requires cancelling of the electrostatic repulsions by salts, which allows approach of clay surfaces close enough to be bridged by adsorbing macromolecules. The amount of acidic charges of the polysaccharides, and especially their location in the molecular structure, governs the bridging mechanism and the resulting tensile strength of the aggregates. The exposure of carboxylate groups located on side chains strongly promotes flocculation. In turn, charges located on the backbone of the polysaccharide are less accessible to interaction, and the flocculation ability of such polysaccharides is lowered. Measurements at different pH indicate that adsorption of acidic polysaccharides occurs via electrostatic interactions on the amphoteric edge surface of clay platelets, whereas neutral polysaccharides rather adsorb via weak interactions. Increased tensile strength in diluted aggregates due to strong surface interactions results in proportionally increased viscosity of the concentrated aggregates.

Combined use of atomic force microscopy, X-ray photoelectron spectroscopy, and secondary ion mass spectrometry for cell surface analysis.

PubMed

Dague, Etienne; Delcorte, Arnaud; Latgé, Jean-Paul; Dufrêne, Yves F

2008-04-01

Understanding the surface properties of microbial cells is a major challenge of current microbiological research and a key to efficiently exploit them in biotechnology. Here, we used three advanced surface analysis techniques with different sensitivity, probing depth, and lateral resolution, that is, in situ atomic force microscopy, X-ray photoelectron spectroscopy, and secondary ion mass spectrometry, to gain insight into the surface properties of the conidia of the human fungal pathogen Aspergillus fumigatus. We show that the native ultrastructure, surface protein and polysaccharide concentrations, and amino acid composition of three mutants affected in hydrophobin production are markedly different from those of the wild-type, thereby providing novel insight into the cell wall architecture of A. fumigatus. The results demonstrate the power of using multiple complementary techniques for probing microbial cell surfaces.

Interfacing nanostructures to biological cells

DOEpatents

Chen, Xing; Bertozzi, Carolyn R.; Zettl, Alexander K.

2012-09-04

Disclosed herein are methods and materials by which nanostructures such as carbon nanotubes, nanorods, etc. are bound to lectins and/or polysaccharides and prepared for administration to cells. Also disclosed are complexes comprising glycosylated nanostructures, which bind selectively to cells expressing glycosylated surface molecules recognized by the lectin. Exemplified is a complex comprising a carbon nanotube functionalized with a lipid-like alkane, linked to a polymer bearing repeated .alpha.-N-acetylgalactosamine sugar groups. This complex is shown to selectively adhere to the surface of living cells, without toxicity. In the exemplified embodiment, adherence is mediated by a multivalent lectin, which binds both to the cells and the .alpha.-N-acetylgalactosamine groups on the nanostructure.

Purification, characterization and anticancer activity of a polysaccharide from Panax ginseng.

PubMed

Li, Cong; Cai, Jianping; Geng, Jingshu; Li, Yinghong; Wang, Zhenyu; Li, Rui

2012-12-01

In this study, we purified a homogeneous polysaccharide (PGPW1) from the root of Panax ginseng. Its molecular weight was estimated to be 3.5×10(5) Da by high performance liquid chromatography (HPLC) and Gas chromatography (GC) analysis identified that PGPW1 contained Glc, Gal, Man and Ara in the molar ratio of 3.3:1.2:0.5:1.1. Furthermore the antitumor potential of PGPW1 on human bladder T24 cells was evaluated in vitro by MTT, lactate dehydrogenase (LDH), wound scratch and transwell motility assays. PGPW1 dose-dependently displayed potent anti-proliferation and anti-metastatic activities. Moreover the modulating effect of PGPW1 on the binding of (3)H-NMS to M3 muscarinic receptors on the surface of T24 cells was evaluated. In muscarinic receptor binding assay, the attenuated expression of M3 muscarinic receptor on the surface of T24 cells by PGPW1 would contribute to its antitumor functions. All the data indicated the potential of its clinical application for the prevention and treatment of bladder cancer metastasis. Copyright © 2012 Elsevier B.V. All rights reserved.

[Gravity resistance, another graviresponse in plants--function of anti-gravitational polysaccharides].

PubMed

Hoson, Takayuki; Wakabayashi, Kazuyuki; Soga, Kouichi

2003-08-01

The involvement of anti-gravitational polysaccharides in gravity resistance, one of two major gravity responses in plants, was discussed. In dicotyledons, xyloglucans are the only cell wall polysaccharides, whose level, molecular size, and metabolic turnover were modified under both hypergravity and microgravity conditions, suggesting that xyloglucans act as anti-gravitational polysaccharides. In monocotyledonous Poaceae, (1-->3),(1-->4)-beta glucans, instead of xyloglucans, were shown to play a role as anti-gravitational polysaccharides. These polysaccharides are also involved in plant responses to other environmental factors, such as light and temperature, and to some phytohormones, such as auxin and ethylene. Thus, the type of anti-gravitational polysaccharides is different between dicotyledons and Poaceae, but such polysaccharides are universally involved in plant responses to environmental and hormonal signals. In gravity resistance, the gravity signal may be received by the plasma membrane mechanoreceptors, transformed and transduced within each cell, and then may modify the processes of synthesis and secretion of the anti-gravitational polysaccharides and the cell wall enzymes responsible for their degradation, as well as the apoplastic pH, leading to the cell wall reinforcement. A series of events inducing gravity resistance are quite independent of those leading to gravitropism.

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.

Gracilaria lemaneiformis polysaccharide as integrin-targeting surface decorator of selenium nanoparticles to achieve enhanced anticancer efficacy.

PubMed

Jiang, Wenting; Fu, Yuanting; Yang, Fang; Yang, Yufeng; Liu, Ting; Zheng, Wenjie; Zeng, Lilan; Chen, Tianfeng

2014-08-27

The poor permeability of glioma parenchyma represents a major limit for antiglioblastoma drug delivery. Gracilaria lemaneiformis polysaccharide (GLP), which has a high binding affinity to αvβ3 integrin overexpressed in glioma cells, was employed in the present study to functionalize selenium nanoparticles (SeNPs) to achieve antiglioblastoma efficacy. GLP-SeNPs showed satisfactory size distribution, high stability, and selectivity between cancer and normal cells. In U87 glioma cell membrane, which has a high integrin expression level, GLP-SeNPs exhibited significantly higher cellular uptake than unmodified SeNPs. As expected, U87 cells exhibited a greater uptake of GLP-SeNPs than C6 cells with low integrin expression level. Furthermore, the internalization of GLP-SeNPs was inhibited by cyclo-(Arg-Gly-Asp-Phe-Lys) peptides, suggesting that cellular uptake into U87 cells and C6 cells occurred via αvβ3 integrin-mediated endocytosis. For U87 cells, the cytotoxicity of SeNPs decorated by GLP was enhanced significantly because of the induction of various apoptosis signaling pathways. Internalized GLP-SeNPs triggered intracellular reactive oxygen species downregulation. Therefore, p53, MAPKs, and AKT pathways were activated to advance cell apoptosis. These findings suggest that surface decoration of nanomaterials with GLP could be an efficient strategy for design and preparation of glioblastoma targeting nanodrugs.

Ultrasound-Assisted Extraction, Antioxidant and Anticancer Activities of the Polysaccharides from Rhynchosia minima Root.

PubMed

Jia, Xuejing; Zhang, Chao; Hu, Jie; He, Muxue; Bao, Jiaolin; Wang, Kai; Li, Peng; Chen, Meiwan; Wan, Jianbo; Su, Huanxing; Zhang, Qingwen; He, Chengwei

2015-11-23

Box-Behnken design (BBD), one of the most common response surface methodology (RSM) methods, was used to optimize the experimental conditions for ultrasound-assisted extraction of polysaccharides from Rhynchosia minima root (PRM). The antioxidant abilities and anticancer activity of purified polysaccharide fractions were also measured. The results showed that optimal extraction parameters were as follows: ultrasound exposure time, 21 min; ratio of water to material, 46 mL/g; ultrasound extraction temperature, 63 °C. Under these conditions, the maximum yield of PRM was 16.95%±0.07%. Furthermore, the main monosaccharides of purified fractions were Ara and Gal. PRM3 and PRM5 exhibited remarkable DPPH radical scavenging activities and reducing power in vitro. PRM3 showed strong inhibitory activities on the growth of MCF-7 cells in vitro. The above results indicate that polysaccharides from R. minima root have the potential to be developed as natural antioxidants and anticancer ingredients for the food and pharmaceutical industries.

Apoptosis of Hepatocellular Carcinoma Cells Induced by Nanoencapsulated Polysaccharides Extracted from Antrodia Camphorata

PubMed Central

Chang, Ke Liang B.; Kong, Zwe-Ling

2015-01-01

Antrodia camphorata is a well-known medicinal mushroom in Taiwan and has been studied for decades, especially with focus on anti-cancer activity. Polysaccharides are the major bioactive compounds reported with anti-cancer activity, but the debates on how they target cells still remain. Research addressing the encapsulation of polysaccharides from A. camphorata extract (ACE) to enhance anti-cancer activity is rare. In this study, ACE polysaccharides were nano-encapsulated in chitosan-silica and silica (expressed as ACE/CS and ACE/S, respectively) to evaluate the apoptosis effect on a hepatoma cell line (Hep G2). The results showed that ACE polysaccharides, ACE/CS and ACE/S all could damage the Hep G2 cell membrane and cause cell death, especially in the ACE/CS group. In apoptosis assays, DNA fragmentation and sub-G1 phase populations were increased, and the mitochondrial membrane potential decreased significantly after treatments. ACE/CS and ACE/S could also increase reactive oxygen species (ROS) generation, induce Fas/APO-1 (apoptosis antigen 1) expression and elevate the proteolytic activities of caspase-3, caspase-8 and caspase-9 in Hep G2 cells. Unsurprisingly, ACE/CS induced a similar apoptosis mechanism at a lower dosage (ACE polysaccharides = 13.2 μg/mL) than those of ACE/S (ACE polysaccharides = 21.2 μg/mL) and ACE polysaccharides (25 μg/mL). Therefore, the encapsulation of ACE polysaccharides by chitosan-silica nanoparticles may provide a viable approach for enhancing anti-tumor efficacy in liver cancer cells. PMID:26327534

Inhibitory effect of saponins and polysaccharides from Radix ranunculi ternati on human gastric cancer BGC823 cells.

PubMed

Niu, Lidan; Zhou, Yingfeng; Sun, Bing; Hu, Junling; Kong, Lingyu; Duan, Sufang

2013-01-01

The effects of different Radix ranunculi ternati extracts on human gastric cancer BGC823 cells were investigated, different methods were used to extract the saponins and polysaccharides from Radix ranunculi ternati, and MTT assay and colony formation assay were used to observe the effects of saponins and polysaccharides from Radix ranunculi ternati on in-vitro cultured human gastric cancer BGC823 cells. The results found that the saponins and polysaccharides from Radix Ranunculi Ternati had certain effects on both the growth and colony formation of human gastric cancer BGC823 cells, while improving the immune function of normal mice, of which saponins had more significant effects than polysaccharides.

Identification, structure, and characterization of an exopolysaccharide produced by Histophilus somni during biofilm formation

PubMed Central

2011-01-01

Background Histophilus somni, a gram-negative coccobacillus, is an obligate inhabitant of bovine and ovine mucosal surfaces, and an opportunistic pathogen responsible for respiratory disease and other systemic infections in cattle and sheep. Capsules are important virulence factors for many pathogenic bacteria, but a capsule has not been identified on H. somni. However, H. somni does form a biofilm in vitro and in vivo, and the biofilm matrix of most bacteria consists of a polysaccharide. Results Following incubation of H. somni under growth-restricting stress conditions, such as during anaerobiosis, stationary phase, or in hypertonic salt, a polysaccharide could be isolated from washed cells or culture supernatant. The polysaccharide was present in large amounts in broth culture sediment after H. somni was grown under low oxygen tension for 4-5 days (conditions favorable to biofilm formation), but not from planktonic cells during log phase growth. Immuno-transmission electron microscopy showed that the polysaccharide was not closely associated with the cell surface, and was of heterogeneous high molecular size by gel electrophoresis, indicating it was an exopolysaccharide (EPS). The EPS was a branched mannose polymer containing some galactose, as determined by structural analysis. The mannose-specific Moringa M lectin and antibodies to the EPS bound to the biofilm matrix, demonstrating that the EPS was a component of the biofilm. The addition of N-acetylneuraminic acid to the growth medium resulted in sialylation of the EPS, and increased biofilm formation. Real-time quantitative reverse transcription-polymerase chain reaction analyses indicated that genes previously identified in a putative polysaccharide locus were upregulated when the bacteria were grown under conditions favorable to a biofilm, compared to planktonic cells. Conclusions H. somni is capable of producing a branching, mannose-galactose EPS polymer under growth conditions favorable to the biofilm phase of growth, and the EPS is a component of the biofilm matrix. The EPS can be sialylated in strains with sialyltransferase activity, resulting in enhanced density of the biofilm, and suggesting that EPS and biofilm formation may be important to persistence in the bovine host. The EPS may be critical to virulence if the biofilm state is required for H. somni to persist in systemic sites. PMID:21854629

Outer membrane proteins related to SusC and SusD are not required for Cytophaga hutchinsonii cellulose utilization.

PubMed

Zhu, Yongtao; Kwiatkowski, Kurt J; Yang, Tengteng; Kharade, Sampada S; Bahr, Constance M; Koropatkin, Nicole M; Liu, Weifeng; McBride, Mark J

2015-08-01

Cytophaga hutchinsonii, a member of the phylum Bacteroidetes, employs a novel collection of cell-associated proteins to digest crystalline cellulose. Other Bacteroidetes rely on cell surface proteins related to the starch utilization system (Sus) proteins SusC and SusD to bind oligosaccharides and import them across the outer membrane for further digestion. These bacteria typically produce dozens of SusC-like porins and SusD-like oligosaccharide-binding proteins to facilitate utilization of diverse polysaccharides. C. hutchinsonii specializes in cellulose digestion and its genome has only two susC-like genes and two susD-like genes. Single and multiple gene deletions were constructed to determine if the susC-like and susD-like genes have roles in cellulose utilization. A mutant lacking all susC-like and all susD-like genes digested cellulose and grew on cellulose as well as wild-type cells. Further, recombinantly expressed SusD-like proteins CHU_0547 and CHU_0554 failed to bind cellulose or β-glucan hemicellulosic polysaccharides. The results suggest that the Bacteroidetes Sus paradigm for polysaccharide utilization may not apply to the cellulolytic bacterium C. hutchinsonii.

[Sorption properties of various polysaccharide matrixes to Lactobacillus plantarum 8RA-3 bacteria].

PubMed

Bondarenko, V M; Larionov, I V; Rybal'chenko, O V; Potokin, I L; Ryzhankova, A V

2011-01-01

Study of sorption properties of various spherical polysaccharide matrixes designated as Spherocell to probiotic Lactobacillus plantarum 8RA-3 bacteria. Industrial strain of L. plantarum 8PA-3 was used. The process of immobilization of lactobacilli on 3 variants of spherical sorbents was studied. The first sorbent - neutral, composed of nonpolar cellulose matrix with ("0") charge, the second--DEAE obtained by modification of cellulose by diethylaminoethyl groups with positive ("+") charge and the third--CM (carboxymethyl) with negative ("-") charge. Cellulose matrixes were designated by us by the term Spherocell. Immobilization of bacterial cells on Spherocell was performed by addition of suspension containing 1.0 x 10(9) CFU/ml. The effect of bacterial immobilization was evaluated by CFU/ ml titration and by electron microscopy. The dependence on matrix charge of adsorption immobilization on sorbent granules of lactobacilli cells was shown. At certain equal parameters (granule size, surface characteristics, charge value) the positively charged matrix sorbed 3-10 times more cells than neutral and 20-25 times more than negatively charged matrix. Each 100-180 microm Spherocell DEAE particle could sorb more than 1000 viable bacterial cells. Positively charged polysaccharide matrix Spherocell DEAE obtained by modification of cellulose by diethylaminoethyl groups is promising for creation of immobilized probiotic preparations.

Functional duality of the cell wall.

PubMed

Latgé, Jean-Paul; Beauvais, Anne

2014-08-01

The polysaccharide cell wall is the extracellular armour of the fungal cell. Although essential in the protection of the fungal cell against aggressive external stresses, the biosynthesis of the polysaccharide core is poorly understood. For a long time it was considered that this cell wall skeleton was a fixed structure whose role was only to be sensed as non-self by the host and consequently trigger the defence response. It is now known that the cell wall polysaccharide composition and localization continuously change to adapt to their environment and that these modifications help the fungus to escape from the immune system. Moreover, cell wall polysaccharides could function as true virulence factors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Both Leukotoxin and Poly-N-Acetylglucosamine Surface Polysaccharide Protect Aggregatibacter actinomycetemcomitans Cells from Macrophage Killing

PubMed Central

Venketaraman, Vishwanath; Lin, Albert K.; Le, Amy; Kachlany, Scott C.; Connell, Nancy D.; Kaplan, Jeffrey B.

2008-01-01

Two virulence factors produced by the periodontopathogen Aggregatibacter actinomycetemcomitans are leukotoxin, a secreted lipoprotein that kills human polymorphonuclear leukocytes and macrophages, and poly-N-acetylglucosamine (PGA), a surface polysaccharide that mediates intercellular adhesion, biofilm formation and detergent resistance. In this study we examined the roles of leukotoxin and PGA in protecting A. actinomycetemcomitans cells from killing by the human macrophage cell line THP-1. Monolayers of THP-1 cells were infected with single-cell suspensions of a wild-type A. actinomycetemcomitans strain, or of isogenic leukotoxin or PGA mutant strains. After 48 h, viable bacteria were enumerated by dilution plating, macrophage morphology was evaluated microscopically, and macrophage viability was measured by a Trypan blue dye exclusion assay. The number of A. actinomycetemcomitans CFUs increased approximately 2-fold in wells infected with the wild-type strain, but decreased by approximately 70–90% in wells infected with the leukotoxin and PGA mutant strains. Infection with the wild-type or leukotoxin mutant strain caused a significant decrease in THP-1 cell viability, whereas infection with the PGA mutant strain did not result in any detectable changes in THP-1 viability. Pre-treatment of wild-type A. actinomycetemcomitans cells with the PGA-hydrolyzing enzyme dispersin B rendered them sensitive to killing by THP-1 cells. We concluded that both leukotoxin and PGA are necessary for evasion of macrophage killing by A. actinomycetemcomitans. PMID:18573331

Histochemistry and ultrastructure of urocytes in the pupae of the stingless bee Melipona quadrifasciata (Hymenoptera: Meliponini).

PubMed

Furtado, Waléria C A; Azevedo, Dihego O; Martins, Gustavo F; Zanuncio, José C; Serrão, José Eduardo

2013-12-01

The main cell types of the adult bee fat body are trophocytes and oenocytes; however, in pupae of some newly emerged bees, trophocytes are modified into cells called urocytes, which possibly function as a substitute for Malpighian tubules during metamorphosis when larval tubules are not functional and/or storage of urate salts is required. This study evaluated the morphology of urocytes in the stingless bee Melipona quadrifasciata and the possibility of maintaining these cells in primary culture. The urocytes M. quadrifasciata are white spherical cells with an irregular surface as observed by stereomicroscopy. They may be found individually or in groups associated with tracheae. Urocytes have a single, small, and spherical nucleus and cytoplasm rich in neutral polysaccharides, lipid droplets, protein, and granules containing calcium and urate salts. Our findings suggest that urocytes play a role in storage of neutral polysaccharides and calcium in M. quadrifasciata pupae and that these cells can be cultured for 72 h.

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.

Inhibitory effects of thymus-independent type 2 antigens on MHC class II-restricted antigen presentation: comparative analysis of carbohydrate structures and the antigen presenting cell.

PubMed

González-Fernández, M; Carrasco-Marín, E; Alvarez-Domínguez, C; Outschoorn, I M; Leyva-Cobián, F

1997-02-25

The role of thymus-independent type 2 (TI-2) antigens (polysaccharides) on the MHC-II-restricted processing of protein antigens was studied in vitro. In general, antigen presentation is inhibited when both peritoneal and splenic macrophages (M phi) as well as Küpffer cells (KC) are preincubated with acidic polysaccharides or branched dextrans. However, the inhibitory effect of neutral polysaccharides was minimal when KC were used as antigen presenting cells (APC). Morphological evaluation of the uptake of fluoresceinated polysaccharides clearly correlates with this selective and differential interference. Polysaccharides do not block MHC-I-restricted antigen presentation. Some chemical characteristics shared by different saccharides seem to be specially related to their potential inhibitory abilities: (i) those where two anomeric carbon atoms of two interlinked sugars and (ii) those containing several sulfate groups per disaccharide repeating unit. No polysaccharide being inhibitory in M phi abrogated antigen processing in other APC: lipopolysaccharide-activated B cells, B lymphoma cells, or dendritic cells (DC). Using radiolabeled polysaccharides it was observed that DC and B cells incorporated less radioactivity as a function of time than M phi. Morphological evaluation of these different APC incubated for extended periods of time with inhibitory concentrations of polysaccharides revealed intense cytoplasmic vacuolization in M phi but not in B cells or DC. The large majority of M phi lysosomes containing polysaccharides fail to fuse with incoming endocytic vesicles and delivery of fluid-phase tracers was reduced, suggesting that indigestible carbohydrates reduced the fusion of these loaded lysosomes with endosomes containing recently internalized tracers. It is suggested that the main causes of this antigen presentation blockade are (i) the chemical characteristics of certain carbohydrates and whether the specific enzymatic machinery for their intracellular degradation exists; and (ii) the different phagocytic abilities of distinct APC populations, fluid-phase pinocytosis and receptor-mediated saccharide uptake, and existence of a differential antigen-processing pathway in M phi and DC or B cells, which could be based on a polysaccharide-inhibited step present in M phi but unaffected or irrelevant in both B cells and DC.

Effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans during chalcopyrite bioleaching

NASA Astrophysics Data System (ADS)

Yu, Run-lan; Liu, Jing; Tan, Jian-xi; Zeng, Wei-min; Shi, Li-juan; Gu, Guo-hua; Qin, Wen-qing; Qiu, Guan-zhou

2014-04-01

The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleaching. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.

Surface chemical studies on selective separation of pyrite and galena in the presence of bacterial cells and metabolic products of Paenibacillus polymyxa.

PubMed

Patra, Partha; Natarajan, K A

2006-06-15

Selective separation of pyrite and galena from mixture of the two minerals was achieved through interaction with cells and metabolic products from a culture of Paenibacillus polymyxa. Adsorption of cells and metabolic products onto minerals and electrokinetic studies of minerals after interaction with cells and metabolic products were carried out to examine the resulting surface modification on the mineral surfaces. Flocculation and flotation techniques were successfully applied in the selective separation of minerals after bacterial interaction. The effect of varying conditions for production of extracellular polysaccharides and protein provided an insight into the possible mechanism involved in microbially induced flocculation and flotation of pyrite and galena.

Polysaccharides from Epimedium koreanum Nakai with immunomodulatory activity and inhibitory effect on tumor growth in LLC-bearing mice.

PubMed

Wang, Chengcheng; Feng, Liang; Su, Jiayan; Cui, Li; Dan Liu; Yan, Jun; Ding, Chuanlin; Tan, Xiaobin; Jia, Xiaobin

2017-07-31

Epimedium koreanum Nakai is documented as tonic herbal in China for over a thousand years and has the potential to enhance the body's immunity according to the theory of traditional Chinese medicine. Polysaccharides are one of the most important effective compounds in Epimedium koreanum Nakai. Accumulating evidence indicated polysaccharides derived from traditional Chinese medicine have potent immune-enhancing properties and relatively nontoxic effects in cancer treatment. However, information about immunological regulation in tumor of Epimedium koreanum Nakai polysaccharides is limited and the reports of purification, characterization of polysaccharides have remained less. The purpose of our study was to further investigate the active polysaccharides from Epimedium koreanum Nakai by evaluating the immune-regulation activities in tumor-bearing mice and provide reasonable explanation for traditional application. We firstly purified Epimedium koreanum polysaccharide (EPS) from crude extracts and evaluated EPS in vitro using immunological experiments including maturation and Ag presentation function of DCs, CD4 T-cell differentiation and secretion of anti-cancer cytokines. In LLC-bearing mice model, we investigated its antitumor activities through evaluation of tumor cell proliferative activity, calculation of immune organ indexes and relative host immune system function tests. Results showed that EPS (180 × 10 4 Da) was composed of mannose (Man), rhamnose (Rha), glucuronic acid (GlcUA), galactosamine (GalN), glucose (Glc), galactose (Gal), arabinose (Ara) and fructose (Fuc). Chemical composition assay indicated EPS was a fraction with 28.20% uronic acid content. FT-IR suggested the presence of pyraoid ring in EPS and SEM displayed smooth surface embedded by several pores. Moreover, Our study suggested EPS could remarkably stimulate macrophages to secrete substantial anti-cancer cytokines and promote maturation as well as Ag presentation function of DCs. Strikingly, CD4 T-cell differentiation and increased INF-γ production stimulated by EPS-activated macrophages were observed in the research. Furthermore, EPS exhibited prominent antitumor activities through regulating host immune system function in LLC-bearing mice. Taken together, experimental findings suggested EPS could be regarded as a potential immune-stimulating modifier for cancer therapy. Our studies demonstrated the polysaccharide (180 × 10 4 Da) purified from Epimedium koreanum Nakai could promote maturation and Ag presentation function of DCs, increase the level of immunomodulatory cytokines and activate CD4 T-cell differentiation. Furthermore, it may inhibit the tumor growth in LLC-bearing mice through regulating host immune system function. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Environmental and Biofilm-dependent Changes in a Bacillus cereus Secondary Cell Wall Polysaccharide*

PubMed Central

Candela, Thomas; Maes, Emmanuel; Garénaux, Estelle; Rombouts, Yoann; Krzewinski, Frédéric; Gohar, Michel; Guérardel, Yann

2011-01-01

Bacterial species from the Bacillus genus, including Bacillus cereus and Bacillus anthracis, synthesize secondary cell wall polymers (SCWP) covalently associated to the peptidoglycan through a phospho-diester linkage. Although such components were observed in a wide panel of B. cereus and B. anthracis strains, the effect of culture conditions or of bacterial growth state on their synthesis has never been addressed. Herein we show that B. cereus ATCC 14579 can synthesize not only one, as previously reported, but two structurally unrelated secondary cell wall polymers (SCWP) polysaccharides. The first of these SCWP, →4)[GlcNAc(β1–3)]GlcNAc(β1–6)[Glc(β1-3)][ManNAc(α1–4)]GalNAc(α1–4)ManNAc(β1→, although presenting an original sequence, fits to the already described the canonical sequence motif of SCWP. In contrast, the second polysaccharide was made up by a totally original sequence, →6)Gal(α1–2)(2-R-hydroxyglutar-5-ylamido)Fuc2NAc4N(α1-6)GlcNAc(β1→, which no equivalent has ever been identified in the Bacillus genus. In addition, we established that the syntheses of these two polysaccharides were differently regulated. The first one is constantly expressed at the surface of the bacteria, whereas the expression of the second is tightly regulated by culture conditions and growth states, planktonic, or biofilm. PMID:21784857

Genomic analysis of Bacteroides fragilis reveals extensive DNA inversions regulating cell surface adaptation

PubMed Central

Kuwahara, Tomomi; Yamashita, Atsushi; Hirakawa, Hideki; Nakayama, Haruyuki; Toh, Hidehiro; Okada, Natsumi; Kuhara, Satoru; Hattori, Masahira; Hayashi, Tetsuya; Ohnishi, Yoshinari

2004-01-01

Bacteroides are predominant human colonic commensals, but the principal pathogenic species, Bacteroides fragilis (BF), lives closely associated with the mucosal surface, whereas a second major species, Bacteroides thetaiotaomicron (BT), concentrates within the colon. We find corresponding differences in their genomes, based on determination of the genome sequence of BF and comparative analysis with BT. Both species have acquired two mechanisms that contribute to their dominance among the colonic microbiota: an exceptional capability to use a wide range of dietary polysaccharides by gene amplification and the capacity to create variable surface antigenicities by multiple DNA inversion systems. However, the gene amplification for polysaccharide assimilation is more developed in BT, in keeping with its internal localization. In contrast, external antigenic structures can be changed more systematically in BF. Thereby, at the mucosal surface, where microbes encounter continuous attack by host defenses, BF evasion of the immune system is favored, and its colonization and infectious potential are increased. PMID:15466707

Ultrasonic-assisted extraction, structure and antitumor activity of polysaccharide from Polygonum multiflorum.

PubMed

Zhu, Weili; Xue, Xiaoping; Zhang, Zhanjun

2016-10-01

Polygonum multiflorum is a popular Chinese herbal medicine with various pharmacological functions. In this study, the ultrasonic-assisted extraction condition, structural characterization and antitumor activity of a polysaccharide from roots of P. multiflorum were investigated. The ultrasonic-assisted extraction condition was optimized by single-factor experiments and response surface methodology. Results showed that the maximum extraction yield (5.49%) was obtained at ultrasonic power 158W, extraction temperature 62°C, extraction time 80min and ratio of water to material 20mL/g. The obtained crude polysaccharides were further purified to afford a neutral and an acidic fraction. The structure of the main neutral polysaccharide (named PPS with molecular weight of 3.26×10(5)Da) was characterized as a linear (1→6)-α-d-glucan by gas chromatography, Fourier transform-infrared spectroscopy, methylation analysis, 1D and 2D nuclear magnetic resonance. At the concentration of 400μg/mL, the inhibitory ratios of PPS on HepG-2 and BGC-823 cells were 53.35% and 38.58%, respectively. Results suggested this polysaccharide could be a potential natural antitumor agent. Copyright © 2016 Elsevier B.V. All rights reserved.

Chondroitin Sulfate Is Indispensable for Pluripotency and Differentiation of Mouse Embryonic Stem Cells

NASA Astrophysics Data System (ADS)

Izumikawa, Tomomi; Sato, Ban; Kitagawa, Hiroshi

2014-01-01

Chondroitin sulfate (CS) proteoglycans are present on the surfaces of virtually all cells and in the extracellular matrix and are required for cytokinesis at early developmental stages. Studies have shown that heparan sulfate (HS) is essential for maintaining mouse embryonic stem cells (ESCs) that are primed for differentiation, whereas the function of CS has not yet been elucidated. To clarify the role of CS, we generated glucuronyltransferase-I-knockout ESCs lacking CS. We found that CS was required to maintain the pluripotency of ESCs and promoted initial ESC commitment to differentiation compared with HS. In addition, CS-A and CS-E polysaccharides, but not CS-C polysaccharides, bound to E-cadherin and enhanced ESC differentiation. Multiple-lineage differentiation was inhibited in chondroitinase ABC-digested wild-type ESCs. Collectively, these results suggest that CS is a novel determinant in controlling the functional integrity of ESCs via binding to E-cadherin.

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.

A Rhizobium leguminosarum CHDL- (Cadherin-Like-) Lectin Participates in Assembly and Remodeling of the Biofilm Matrix

PubMed Central

Vozza, Nicolás F.; Abdian, Patricia L.; Russo, Daniela M.; Mongiardini, Elías J.; Lodeiro, Aníbal R.; Molin, Søren; Zorreguieta, Angeles

2016-01-01

In natural environments most bacteria live in multicellular structures called biofilms. These cell aggregates are enclosed in a self-produced polymeric extracellular matrix, which protects the cells, provides mechanical stability and mediates cellular cohesion and adhesion to surfaces. Although important advances were made in the identification of the genetic and extracellular factors required for biofilm formation, the mechanisms leading to biofilm matrix assembly, and the roles of extracellular proteins in these processes are still poorly understood. The symbiont Rhizobium leguminosarum requires the synthesis of the acidic exopolysaccharide and the PrsDE secretion system to develop a mature biofilm. PrsDE is responsible for the secretion of the Rap family of proteins that share one or two Ra/CHDL (cadherin-like-) domains. RapA2 is a calcium-dependent lectin with a cadherin-like β sheet structure that specifically recognizes the exopolysaccharide, either as a capsular polysaccharide (CPS) or in its released form [extracellular polysaccharide (EPS)]. In this study, using gain and loss of function approaches combined with phenotypic and microscopic studies we demonstrated that RapA lectins are involved in biofilm matrix development and cellular cohesion. While the absence of any RapA protein increased the compactness of bacterial aggregates, high levels of RapA1 expanded distances between cells and favored the production of a dense matrix network. Whereas endogenous RapA(s) are predominantly located at one bacterial pole, we found that under overproduction conditions, RapA1 surrounded the cell in a way that was reminiscent of the capsule. Accordingly, polysaccharide analyses showed that the RapA lectins promote CPS formation at the expense of lower EPS production. Besides, polysaccharide analysis suggests that RapA modulates the EPS size profile. Collectively, these results show that the interaction of RapA lectins with the polysaccharide is involved in rhizobial biofilm matrix assembly and remodeling. PMID:27790205

Immunomodulatory and anticancer potential of Gan cao (Glycyrrhiza uralensis Fisch.) polysaccharides by CT-26 colon carcinoma cell growth inhibition and cytokine IL-7 upregulation in vitro.

PubMed

Ayeka, Peter Amwoga; Bian, Yuhong; Mwitari, Peter Githaiga; Chu, Xiaoqian; Zhang, Yanjun; Uzayisenga, Rosette; Otachi, Elick Onyango

2016-07-11

Chinese licorice, (Glycyrrhiza uralensis Fisch.) is one of the commonly prescribed herbs in Traditional Chinese Medicine (TCM). Gancao, as commonly known in China, is associated with immune-modulating and anti-tumor potential though the mechanism of action is not well known. In this study, we investigated the in vitro immunomodulatory and antitumor potential of Glycyrrhiza uralensis polysaccharides fractions of high molecular weight (fraction A), low molecular weight (fraction B) and crude extract (fraction C). Cell proliferation and cytotoxicity was investigated using Cell Counting kit 8 (CCK-8) on Intestinal epithelial cell line (IEC-6) and Colon carcinoma cell line (CT-26). IL-7 gene expression relative to GAPDH was analysed using Real time PCR. The stimulation and viability of T lymphocytes was determined by Trypan blue exclusion assay. G.uralensis polysaccharides did not inhibit proliferation of IEC-6 cells even at high concentration. The ED50 was found to be 100 μg/ml. On the other hand, the polysaccharides inhibited the proliferation of cancer cells (CT-26) at a concentration of ≤50 μg/ml. Within 72 h of treatment with the polysaccharides, expression of IL-7 gene was up-regulated over 2 times. It was also noted that, IEC-6 cells secrete IL-7 cytokine into media when treated with G.uralensis polysaccharides. The secreted IL-7 stimulated proliferation of freshly isolated T lymphocytes within 6 h. The effect of the polysaccharides were found to be molecular weight depended, with low molecular weight having a profound effect compared to high molecular weight and total crude extract. Our findings indicate that G.uralensis polysaccharides especially those of low molecular weight have a potential as anticancer agents. Of great importance, is the ability of the polysaccharides to up-regulate anticancer cytokine IL-7, which is important in proliferation and maturation of immune cells and it is associated with better prognosis in cancer. Therefore, immunomodulation is a possible mode of action of the polysaccharides in cancer therapy.

Molecular Dissection of Xyloglucan Recognition in a Prominent Human Gut Symbiont

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

Tauzin, Alexandra S.; Kwiatkowski, Kurt J.; Orlovsky, Nicole I.

Polysaccharide utilization loci (PUL) within the genomes of resident human gutBacteroidetesare central to the metabolism of the otherwise indigestible complex carbohydrates known as “dietary fiber.” However, functional characterization of PUL lags significantly behind sequencing efforts, which limits physiological understanding of the human-bacterial symbiosis. In particular, the molecular basis of complex polysaccharide recognition, an essential prerequisite to hydrolysis by cell surface glycosidases and subsequent metabolism, is generally poorly understood. Here, we present the biochemical, structural, and reverse genetic characterization of two unique cell surface glycan-binding proteins (SGBPs) encoded by a xyloglucan utilization locus (XyGUL) fromBacteroides ovatus, which are integral to growthmore » on this key dietary vegetable polysaccharide. Biochemical analysis reveals that these outer membrane-anchored proteins are in fact exquisitely specific for the highly branched xyloglucan (XyG) polysaccharide. The crystal structure of SGBP-A, a SusD homolog, with a bound XyG tetradecasaccharide reveals an extended carbohydrate-binding platform that primarily relies on recognition of the β-glucan backbone. The unique, tetra-modular structure of SGBP-B is comprised of tandem Ig-like folds, with XyG binding mediated at the distal C-terminal domain. Despite displaying similar affinities for XyG, reverse-genetic analysis reveals that SGBP-B is only required for the efficient capture of smaller oligosaccharides, whereas the presence of SGBP-A is more critical than its carbohydrate-binding ability for growth on XyG. Finally, together, these data demonstrate that SGBP-A and SGBP-B play complementary, specialized roles in carbohydrate capture byB. ovatusand elaborate a model of how vegetable xyloglucans are accessed by theBacteroidetes.« less

Molecular Dissection of Xyloglucan Recognition in a Prominent Human Gut Symbiont

DOE PAGES

Tauzin, Alexandra S.; Kwiatkowski, Kurt J.; Orlovsky, Nicole I.; ...

2016-04-26

Polysaccharide utilization loci (PUL) within the genomes of resident human gutBacteroidetesare central to the metabolism of the otherwise indigestible complex carbohydrates known as “dietary fiber.” However, functional characterization of PUL lags significantly behind sequencing efforts, which limits physiological understanding of the human-bacterial symbiosis. In particular, the molecular basis of complex polysaccharide recognition, an essential prerequisite to hydrolysis by cell surface glycosidases and subsequent metabolism, is generally poorly understood. Here, we present the biochemical, structural, and reverse genetic characterization of two unique cell surface glycan-binding proteins (SGBPs) encoded by a xyloglucan utilization locus (XyGUL) fromBacteroides ovatus, which are integral to growthmore » on this key dietary vegetable polysaccharide. Biochemical analysis reveals that these outer membrane-anchored proteins are in fact exquisitely specific for the highly branched xyloglucan (XyG) polysaccharide. The crystal structure of SGBP-A, a SusD homolog, with a bound XyG tetradecasaccharide reveals an extended carbohydrate-binding platform that primarily relies on recognition of the β-glucan backbone. The unique, tetra-modular structure of SGBP-B is comprised of tandem Ig-like folds, with XyG binding mediated at the distal C-terminal domain. Despite displaying similar affinities for XyG, reverse-genetic analysis reveals that SGBP-B is only required for the efficient capture of smaller oligosaccharides, whereas the presence of SGBP-A is more critical than its carbohydrate-binding ability for growth on XyG. Finally, together, these data demonstrate that SGBP-A and SGBP-B play complementary, specialized roles in carbohydrate capture byB. ovatusand elaborate a model of how vegetable xyloglucans are accessed by theBacteroidetes.« less

Molecular Dissection of Xyloglucan Recognition in a Prominent Human Gut Symbiont

PubMed Central

Tauzin, Alexandra S.; Kwiatkowski, Kurt J.; Orlovsky, Nicole I.; Smith, Christopher J.; Creagh, A. Louise; Haynes, Charles A.; Wawrzak, Zdzislaw

2016-01-01

ABSTRACT Polysaccharide utilization loci (PUL) within the genomes of resident human gut Bacteroidetes are central to the metabolism of the otherwise indigestible complex carbohydrates known as “dietary fiber.” However, functional characterization of PUL lags significantly behind sequencing efforts, which limits physiological understanding of the human-bacterial symbiosis. In particular, the molecular basis of complex polysaccharide recognition, an essential prerequisite to hydrolysis by cell surface glycosidases and subsequent metabolism, is generally poorly understood. Here, we present the biochemical, structural, and reverse genetic characterization of two unique cell surface glycan-binding proteins (SGBPs) encoded by a xyloglucan utilization locus (XyGUL) from Bacteroides ovatus, which are integral to growth on this key dietary vegetable polysaccharide. Biochemical analysis reveals that these outer membrane-anchored proteins are in fact exquisitely specific for the highly branched xyloglucan (XyG) polysaccharide. The crystal structure of SGBP-A, a SusD homolog, with a bound XyG tetradecasaccharide reveals an extended carbohydrate-binding platform that primarily relies on recognition of the β-glucan backbone. The unique, tetra-modular structure of SGBP-B is comprised of tandem Ig-like folds, with XyG binding mediated at the distal C-terminal domain. Despite displaying similar affinities for XyG, reverse-genetic analysis reveals that SGBP-B is only required for the efficient capture of smaller oligosaccharides, whereas the presence of SGBP-A is more critical than its carbohydrate-binding ability for growth on XyG. Together, these data demonstrate that SGBP-A and SGBP-B play complementary, specialized roles in carbohydrate capture by B. ovatus and elaborate a model of how vegetable xyloglucans are accessed by the Bacteroidetes. PMID:27118585

The Modulation of Adaptive Immune Responses by Bacterial Zwitterionic Polysaccharides

PubMed Central

Stephen, Tom Li; Groneck, Laura; Kalka-Moll, Wiltrud Maria

2010-01-01

The detection of pathogen-derived molecules as foreign particles by adaptive immune cells triggers T and B lymphocytes to mount protective cellular and humoral responses, respectively. Recent immunological advances elucidated that proteins and some lipids are the principle biological molecules that induce protective T cell responses during microbial infections. Polysaccharides are important components of microbial pathogens and many vaccines. However, research concerning the activation of the adaptive immune system by polysaccharides gained interest only recently. Traditionally, polysaccharides were considered to be T cell-independent antigens that did not directly activate T cells or induce protective immune responses. Here, we review several recent advances in “carbohydrate immunobiology”. A group of bacterial polysaccharides that are known as “zwitterionic polysaccharides (ZPSs)” were recently identified as potent immune modulators. The immunomodulatory effect of ZPSs required antigen processing and presentation by antigen presenting cells, the activation of CD4 T cells and subpopulations of CD8 T cells and the modulation of host cytokine responses. In this review, we also discuss the potential use of these unique immunomodulatory ZPSs in new vaccination strategies against chronic inflammatory conditions, autoimmunity, infectious diseases, allergies and asthmatic conditions. PMID:21234388

Isolation and antiviral activity of water-soluble Cynomorium songaricum Rupr. polysaccharides.

PubMed

Tuvaanjav, Suvdmaa; Shuqin, Han; Komata, Masashi; Ma, Chunjie; Kanamoto, Taisei; Nakashima, Hideki; Yoshida, Takashi

2016-01-01

The plant, Cynomorium songaricum Rupr., is used as a traditional medicine in China and Mongolia. In the present study, two new water-soluble polysaccharides isolated from C. songaricum Rupr. were purified by successive Sephadex G-75 and G-50 column chromatographies and then characterized by high resolution NMR and IR spectroscopies. The molecular weights of two polysaccharides were determined by an aqueous GPC to be [Formula: see text] = 3.7 × 10(4) and 1.0 × 10(4), respectively. In addition, it was found that the polysaccharide with the larger molecular weight was an acidic polysaccharide. It was found that the iodine-starch reaction of both isolated polysaccharides was negative and the methylation analysis gave 2, 4, 6-tri-O-methyl alditol acetate as a main product. NMR and IR measurements and sugar analysis revealed that both polysaccharides had a (1 → 3)-α-d-glucopyranosidic main chain with a small number of branches. After sulfation, the sulfated C. songaricum Rupr. polysaccharides were found to have a potent inhibitory effect on HIV infection of MT-4 cells at a 50% effective concentration of 0.3-0.4 μg/ml, a concentration that has almost the same high activity as standard dextran and curdlan sulfates, EC50 = 0.35 and 0.14 μg/ml, respectively. The 50% cytotoxic concentration was low, CC50>1000 μg/ml. In addition, the interaction between the sulfated polysaccharides and poly-l-lysine as a model protein compound was investigated by a surface plasmon resonance to reveal the anti-HIV mechanism.

7-Day Biodefense: Engineered Nanoparticle for Virus Elimination by Opsonization (ENVELOP)

DTIC Science & Technology

2013-12-10

spectrum for LSTc, specifically the identity of the four distinct monosaccharides and the presence of 2→6 sialic acid at stoichimetric levels. 7-Day...A. Previous studies definitively demonstrated that cell surface heparan sulfate, a complex highly charged polysaccharide , plays an important role in

The Pseudomonas aeruginosa PSL Polysaccharide Is a Social but Noncheatable Trait in Biofilms.

PubMed

Irie, Yasuhiko; Roberts, Aled E L; Kragh, Kasper N; Gordon, Vernita D; Hutchison, Jaime; Allen, Rosalind J; Melaugh, Gavin; Bjarnsholt, Thomas; West, Stuart A; Diggle, Stephen P

2017-06-20

Extracellular polysaccharides are compounds secreted by microorganisms into the surrounding environment, and they are important for surface attachment and maintaining structural integrity within biofilms. The social nature of many extracellular polysaccharides remains unclear, and it has been suggested that they could function as either cooperative public goods or as traits that provide a competitive advantage. Here, we empirically tested the cooperative nature of the PSL polysaccharide, which is crucial for the formation of biofilms in Pseudomonas aeruginosa We show that (i) PSL is not metabolically costly to produce; (ii) PSL provides population-level benefits in biofilms, for both growth and antibiotic tolerance; (iii) the benefits of PSL production are social and are shared with other cells; (iv) the benefits of PSL production appear to be preferentially directed toward cells which produce PSL; (v) cells which do not produce PSL are unable to successfully exploit cells which produce PSL. Taken together, this suggests that PSL is a social but relatively nonexploitable trait and that growth within biofilms selects for PSL-producing strains, even when multiple strains are on a patch (low relatedness at the patch level). IMPORTANCE Many studies have shown that bacterial traits, such as siderophores and quorum sensing, are social in nature. This has led to an impression that secreted traits act as public goods, which are costly to produce but benefit both the producing cell and its surrounding neighbors. Theories and subsequent experiments have shown that such traits are exploitable by asocial cheats, but we show here that this does not always hold true. We demonstrate that the Pseudomonas aeruginosa exopolysaccharide PSL provides social benefits to populations but that it is nonexploitable, because most of the fitness benefits accrue to PSL-producing cells. Our work builds on an increasing body of work showing that secreted traits can have both private and public benefits to cells. Copyright © 2017 Irie et al.

Assembly and development of the Pseudomonas aeruginosa biofilm matrix.

PubMed

Ma, Luyan; Conover, Matthew; Lu, Haiping; Parsek, Matthew R; Bayles, Kenneth; Wozniak, Daniel J

2009-03-01

Virtually all cells living in multicellular structures such as tissues and organs are encased in an extracellular matrix. One of the most important features of a biofilm is the extracellular polymeric substance that functions as a matrix, holding bacterial cells together. Yet very little is known about how the matrix forms or how matrix components encase bacteria during biofilm development. Pseudomonas aeruginosa forms environmentally and clinically relevant biofilms and is a paradigm organism for the study of biofilms. The extracellular polymeric substance of P. aeruginosa biofilms is an ill-defined mix of polysaccharides, nucleic acids, and proteins. Here, we directly visualize the product of the polysaccharide synthesis locus (Psl exopolysaccharide) at different stages of biofilm development. During attachment, Psl is anchored on the cell surface in a helical pattern. This promotes cell-cell interactions and assembly of a matrix, which holds bacteria in the biofilm and on the surface. Chemical dissociation of Psl from the bacterial surface disrupted the Psl matrix as well as the biofilm structure. During biofilm maturation, Psl accumulates on the periphery of 3-D-structured microcolonies, resulting in a Psl matrix-free cavity in the microcolony center. At the dispersion stage, swimming cells appear in this matrix cavity. Dead cells and extracellular DNA (eDNA) are also concentrated in the Psl matrix-free area. Deletion of genes that control cell death and autolysis affects the formation of the matrix cavity and microcolony dispersion. These data provide a mechanism for how P. aeruginosa builds a matrix and subsequently a cavity to free a portion of cells for seeding dispersal. Direct visualization reveals that Psl is a key scaffolding matrix component and opens up avenues for therapeutics of biofilm-related complications.

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

Structural Characterization of Mannan Cell Wall Polysaccharides in Plants Using PACE

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

Pidatala, Venkataramana R.; Mahboubi, Amir; Mortimer, Jenny C.

Plant cell wall polysaccharides are notoriously difficult to analyze, and most methods require expensive equipment, skilled operators, and large amounts of purified material. Here, we describe a simple method for gaining detailed polysaccharide structural information, including resolution of structural isomers. For polysaccharide analysis by gel electrophoresis (PACE), plant cell wall material is hydrolyzed with glycosyl hydrolases specific to the polysaccharide of interest (e.g., mannanases for mannan). Large format polyacrylamide gels are then used to separate the released oligosaccharides, which have been fluorescently labeled. Gels can be visualized with a modified gel imaging system (see Table of Materials). The resulting oligosaccharidemore » fingerprint can either be compared qualitatively or, with replication, quantitatively. Linkage and branching information can be established using additional glycosyl hydrolases (e.g., mannosidases and galactosidases). Whilst this protocol describes a method for analyzing glucomannan structure, it can be applied to any polysaccharide for which characterized glycosyl hydrolases exist. Alternatively, it can be used to characterize novel glycosyl hydrolases using defined polysaccharide substrates.« less

Structural Characterization of Mannan Cell Wall Polysaccharides in Plants Using PACE.

PubMed

Pidatala, Venkataramana R; Mahboubi, Amir; Mortimer, Jenny C

2017-10-16

Plant cell wall polysaccharides are notoriously difficult to analyze, and most methods require expensive equipment, skilled operators, and large amounts of purified material. Here, we describe a simple method for gaining detailed polysaccharide structural information, including resolution of structural isomers. For polysaccharide analysis by gel electrophoresis (PACE), plant cell wall material is hydrolyzed with glycosyl hydrolases specific to the polysaccharide of interest (e.g., mannanases for mannan). Large format polyacrylamide gels are then used to separate the released oligosaccharides, which have been fluorescently labeled. Gels can be visualized with a modified gel imaging system (see Table of Materials). The resulting oligosaccharide fingerprint can either be compared qualitatively or, with replication, quantitatively. Linkage and branching information can be established using additional glycosyl hydrolases (e.g., mannosidases and galactosidases). Whilst this protocol describes a method for analyzing glucomannan structure, it can be applied to any polysaccharide for which characterized glycosyl hydrolases exist. Alternatively, it can be used to characterize novel glycosyl hydrolases using defined polysaccharide substrates.

Structural Characterization of Mannan Cell Wall Polysaccharides in Plants Using PACE

DOE PAGES

Pidatala, Venkataramana R.; Mahboubi, Amir; Mortimer, Jenny C.

2017-10-16

Plant cell wall polysaccharides are notoriously difficult to analyze, and most methods require expensive equipment, skilled operators, and large amounts of purified material. Here, we describe a simple method for gaining detailed polysaccharide structural information, including resolution of structural isomers. For polysaccharide analysis by gel electrophoresis (PACE), plant cell wall material is hydrolyzed with glycosyl hydrolases specific to the polysaccharide of interest (e.g., mannanases for mannan). Large format polyacrylamide gels are then used to separate the released oligosaccharides, which have been fluorescently labeled. Gels can be visualized with a modified gel imaging system (see Table of Materials). The resulting oligosaccharidemore » fingerprint can either be compared qualitatively or, with replication, quantitatively. Linkage and branching information can be established using additional glycosyl hydrolases (e.g., mannosidases and galactosidases). Whilst this protocol describes a method for analyzing glucomannan structure, it can be applied to any polysaccharide for which characterized glycosyl hydrolases exist. Alternatively, it can be used to characterize novel glycosyl hydrolases using defined polysaccharide substrates.« less

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

Natural Poly- and Oligosaccharides as Novel Delivery Systems for Plant Protection Compounds.

PubMed

Selyutina, O Yu; Apanasenko, I E; Khalikov, S S; Polyakov, N E

2017-08-09

To increase the bioavailability of plant protection products, we have applied a new approach based on noncovalent association with natural water-soluble polysaccharides and oligosaccharides as delivery systems (DSs). The mechanochemical technique has been applied to prepare the solid-state nanodispersed compositions of antidote 1,8-naphthalic anhydride (NA) with arabinogalactan, sodium salt of carboxymethylcellulose, and glycyrrhizin as DSs. The effect of DSs on the solubility and the penetration of NA into the seeds of barley and wheat has been investigated by various physicochemical techniques. All DSs considerably enhance the solubility of NA and improve its penetration into the grain. The influence of polysaccharides and oligosaccharides on artificial lipid membranes was studied by the NMR relaxation method. It was concluded that the effect of polysaccharides and oligosaccharides on the penetration efficacy of plant protection products might be associated with the detected solubility enhancement and the affinity of DSs to the surface of cell membranes.

Assembly and Development of the Pseudomonas aeruginosa Biofilm Matrix

PubMed Central

Ma, Luyan; Conover, Matthew; Lu, Haiping; Parsek, Matthew R.; Bayles, Kenneth; Wozniak, Daniel J.

2009-01-01

Virtually all cells living in multicellular structures such as tissues and organs are encased in an extracellular matrix. One of the most important features of a biofilm is the extracellular polymeric substance that functions as a matrix, holding bacterial cells together. Yet very little is known about how the matrix forms or how matrix components encase bacteria during biofilm development. Pseudomonas aeruginosa forms environmentally and clinically relevant biofilms and is a paradigm organism for the study of biofilms. The extracellular polymeric substance of P. aeruginosa biofilms is an ill-defined mix of polysaccharides, nucleic acids, and proteins. Here, we directly visualize the product of the polysaccharide synthesis locus (Psl exopolysaccharide) at different stages of biofilm development. During attachment, Psl is anchored on the cell surface in a helical pattern. This promotes cell–cell interactions and assembly of a matrix, which holds bacteria in the biofilm and on the surface. Chemical dissociation of Psl from the bacterial surface disrupted the Psl matrix as well as the biofilm structure. During biofilm maturation, Psl accumulates on the periphery of 3-D-structured microcolonies, resulting in a Psl matrix-free cavity in the microcolony center. At the dispersion stage, swimming cells appear in this matrix cavity. Dead cells and extracellular DNA (eDNA) are also concentrated in the Psl matrix-free area. Deletion of genes that control cell death and autolysis affects the formation of the matrix cavity and microcolony dispersion. These data provide a mechanism for how P. aeruginosa builds a matrix and subsequently a cavity to free a portion of cells for seeding dispersal. Direct visualization reveals that Psl is a key scaffolding matrix component and opens up avenues for therapeutics of biofilm-related complications. PMID:19325879

Biofilm Matrix Proteins.

PubMed

Fong, Jiunn N C; Yildiz, Fitnat H

2015-04-01

Proteinaceous components of the biofilm matrix include secreted extracellular proteins, cell surface adhesins, and protein subunits of cell appendages such as flagella and pili. Biofilm matrix proteins play diverse roles in biofilm formation and dissolution. They are involved in attaching cells to surfaces, stabilizing the biofilm matrix via interactions with exopolysaccharide and nucleic acid components, developing three-dimensional biofilm architectures, and dissolving biofilm matrix via enzymatic degradation of polysaccharides, proteins, and nucleic acids. In this article, we will review functions of matrix proteins in a selected set of microorganisms, studies of the matrix proteomes of Vibrio cholerae and Pseudomonas aeruginosa, and roles of outer membrane vesicles and of nucleoid-binding proteins in biofilm formation.

Anticancer effects of deproteinized asparagus polysaccharide on hepatocellular carcinoma in vitro and in vivo.

PubMed

Xiang, Jianfeng; Xiang, Yanjie; Lin, Shengming; Xin, Dongwei; Liu, Xiaoyu; Weng, Lingling; Chen, Tao; Zhang, Minguang

2014-04-01

Hepatocellular carcinoma (HCC) is one of the most aggressive malignancies in the world whose chemoprevention became increasingly important in HCC treatment. Although the anticancer effects of asparagus constituents have been investigated in several cancers, its effects on hepatocellular carcinoma have not been fully studied. In this study, we investigated the anticancer effects of the deproteinized asparagus polysaccharide on the hepatocellular carcinoma cells using the in vitro and in vivo experimental model. Our data showed that deproteinized asparagus polysaccharide might act as an effective inhibitor on cell growth in vitro and in vivo and exert potent selective cytotoxicity against human hepatocellular carcinoma Hep3B and HepG2 cells. Further study showed that it could potently induce cell apoptosis and G2/M cell cycle arrest in the more sensitive Hep3B and HepG2 cell lines. Moreover, deproteinized asparagus polysaccharide potentiated the effects of mitomycin both in vitro and in vivo. Mechanistic studies revealed that deproteinized asparagus polysaccharide might exert its activity through an apoptosis-associated pathway by modulating the expression of Bax, Bcl-2, and caspase-3. In conclusion, deproteinized asparagus polysaccharide exhibited significant anticancer activity against hepatocellular carcinoma cells and could sensitize the tumoricidal effects of mitomycin, indicating that it is a potential therapeutic agent (or chemosensitizer) for liver cancer therapy.

Surface Structure Characterization of Aspergillus fumigatus Conidia Mutated in the Melanin Synthesis Pathway and Their Human Cellular Immune Response

PubMed Central

Bayry, Jagadeesh; Beaussart, Audrey; Dufrêne, Yves F.; Sharma, Meenu; Bansal, Kushagra; Kniemeyer, Olaf; Aimanianda, Vishukumar; Brakhage, Axel A.; Kaveri, Srini V.; Kwon-Chung, Kyung J.

2014-01-01

In Aspergillus fumigatus, the conidial surface contains dihydroxynaphthalene (DHN)-melanin. Six-clustered gene products have been identified that mediate sequential catalysis of DHN-melanin biosynthesis. Melanin thus produced is known to be a virulence factor, protecting the fungus from the host defense mechanisms. In the present study, individual deletion of the genes involved in the initial three steps of melanin biosynthesis resulted in an altered conidial surface with masked surface rodlet layer, leaky cell wall allowing the deposition of proteins on the cell surface and exposing the otherwise-masked cell wall polysaccharides at the surface. Melanin as such was immunologically inert; however, deletion mutant conidia with modified surfaces could activate human dendritic cells and the subsequent cytokine production in contrast to the wild-type conidia. Cell surface defects were rectified in the conidia mutated in downstream melanin biosynthetic pathway, and maximum immune inertness was observed upon synthesis of vermelone onward. These observations suggest that although melanin as such is an immunologically inert material, it confers virulence by facilitating proper formation of the A. fumigatus conidial surface. PMID:24818666

Extracellular vesicles from Paracoccidioides pathogenic species transport polysaccharide and expose ligands for DC-SIGN receptors

DOE PAGES

da Silva, Roberta Peres; Heiss, Christian; Black, Ian; ...

2015-09-21

Extracellular vesicles (EVs) mediate non-conventional transport of molecules across the fungal cell wall. We aimed at describing the carbohydrate composition and surface carbohydrate epitopes of EVs isolated from the pathogenic fungi Paracoccidioides brasiliensis and P. lutzii using standard procedures. Total EV carbohydrates were ethanol-precipitated from preparations depleted of lipids and proteins, then analyzed by chemical degradation, gas chromatography-mass spectrometry, nuclear magnetic resonance and size-exclusion chromatography. EV glycosyl residues of Glc, Man, and Gal comprised most probably two major components: a high molecular mass 4,6-α-glucan and a galactofuranosylmannan, possibly an oligomer, bearing a 2-α-Manp main chain linked to β-Galf (1,3) andmore » α-Manp (1,6) end units. The results also suggested the presence of small amounts of a (1→6)- Manp polymer, (1→3)-glucan and (1→6)-glucan. Glycan microarrays allowed identification of EV surface lectin(s), while plant lectin microarray profiling revealed terminal Man and GlcNAc residues exposed at the EVs surface. Mammalian lectin microarray profiling showed that DC-SIGN receptors recognized surface carbohydrate in Paracoccidioides EVs. Our results suggest that oligosaccharides, cytoplasmic storage, and cell wall polysaccharides can be exported in fungal EVs, which also expose surface PAMPs and lectins. As a result, the role of these newly identified components in the interaction with the host remains to be unraveled.« less

Extracellular vesicles from Paracoccidioides pathogenic species transport polysaccharide and expose ligands for DC-SIGN receptors

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

da Silva, Roberta Peres; Heiss, Christian; Black, Ian

Extracellular vesicles (EVs) mediate non-conventional transport of molecules across the fungal cell wall. We aimed at describing the carbohydrate composition and surface carbohydrate epitopes of EVs isolated from the pathogenic fungi Paracoccidioides brasiliensis and P. lutzii using standard procedures. Total EV carbohydrates were ethanol-precipitated from preparations depleted of lipids and proteins, then analyzed by chemical degradation, gas chromatography-mass spectrometry, nuclear magnetic resonance and size-exclusion chromatography. EV glycosyl residues of Glc, Man, and Gal comprised most probably two major components: a high molecular mass 4,6-α-glucan and a galactofuranosylmannan, possibly an oligomer, bearing a 2-α-Manp main chain linked to β-Galf (1,3) andmore » α-Manp (1,6) end units. The results also suggested the presence of small amounts of a (1→6)- Manp polymer, (1→3)-glucan and (1→6)-glucan. Glycan microarrays allowed identification of EV surface lectin(s), while plant lectin microarray profiling revealed terminal Man and GlcNAc residues exposed at the EVs surface. Mammalian lectin microarray profiling showed that DC-SIGN receptors recognized surface carbohydrate in Paracoccidioides EVs. Our results suggest that oligosaccharides, cytoplasmic storage, and cell wall polysaccharides can be exported in fungal EVs, which also expose surface PAMPs and lectins. As a result, the role of these newly identified components in the interaction with the host remains to be unraveled.« less

Molecular characteristics of sulfated polysaccharides from Monostroma nitidum and their in vitro anticancer and immunomodulatory activities.

PubMed

Karnjanapratum, Supatra; You, SangGuan

2011-03-01

We investigated water-soluble sulfated polysaccharides isolated from Monostroma nitidum using ion-exchange chromatography to determine their molecular characteristics and biological activities. The crude and fractionated polysaccharides (F(1), F(2), and F(3)) consisted mostly of carbohydrates (58.3-91.9%), uronic acids (0-21.8%) and sulfates (1.8-17.7%) as well as varying amounts of proteins (1.6-9.4%). Their monosaccharide levels were significantly different including rhamnose (0-95.7%) and glucose (0-98.6%) content with small amounts of xylose (0.8-4.3%). These polysaccharides contained one or two subfractions with average molecular weights (M(w)) ranging from 94.4 to 1387×10(3) g/mol. The in vitro inhibitory activity (≤75%) of the polysaccharides on a human cancer cell line (AGS) suggested that the polysaccharides had direct cytotoxic effects on the cancer cells. In addition, these hetero-polysaccharides (from the crude and F(1) and F(2) fractions) stimulated a macrophage cell line, Raw 264.7 cells, inducing considerable NO and PGE(2), production, which suggested that they could be strong immunomodulators. Copyright © 2010 Elsevier B.V. All rights reserved.

Human Infant Memory B Cell and CD4+ T Cell Responses to HibMenCY-TT Glyco-Conjugate Vaccine

PubMed Central

Fuery, Angela; Richmond, Peter C.; Currie, Andrew J.

2015-01-01

Carrier-specific T cell and polysaccharide-specific B cell memory responses are not well characterised in infants following glyco-conjugate vaccination. We aimed to determine if the number of Meningococcal (Men) C- and Y- specific memory B cells and; number and quality of Tetanus Toxoid (TT) carrier-specific memory CD4+ T cells are associated with polysaccharide-specific IgG post HibMenCY-TT vaccination. Healthy infants received HibMenCY-TT vaccine at 2, 4 and 6 months with a booster at 12 months. Peripheral blood mononuclear cells were isolated and polysaccharide-specific memory B cells enumerated using ELISpot. TT-specific memory CD4+ T cells were detected and phenotyped based on CD154 expression and intracellular TNF-α, IL-2 and IFN-γ expression following stimulation. Functional polysaccharide-specific IgG titres were measured using the serum bactericidal activity (SBA) assay. Polysaccharide-specific Men C- but not Men Y- specific memory B cell frequencies pre-boost (12 months) were significantly associated with post-boost (13 months) SBA titres. Regression analysis showed no association between memory B cell frequencies post-priming (at 6 or 7 months) and SBA at 12 months or 13 months. TT-specific CD4+ T cells were detected at frequencies between 0.001 and 0.112 as a percentage of CD3+ T cells, but their numbers were not associated with SBA titres. There were significant negative associations between SBA titres at M13 and cytokine expression at M7 and M12. Conclusion: Induction of persistent polysaccharide-specific memory B cells prior to boosting is an important determinant of secondary IgG responses in infants. However, polysaccharide-specific functional IgG responses appear to be independent of the number and quality of circulating carrier-specific CD4+ T cells after priming. PMID:26191794

Mucilage processing and secretion in the green alga closterium. I. Cytology and biochemistry

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

Domozych, C.R.; Plante, K.; Blais, P.

1993-10-01

Placoderm desmids (Conjugales, Chlorophyta) such as Closterium exhibit a gliding locomotory behavior. This results from the forceful extrusion of an acidic polysaccharide from one pole of the cell causing the cell to glide in the opposite direction. A biochemical and cytological analysis of gliding behavior was performed. The mucilage is a high molecular weight polysaccharide rich in glucuronic acid and fucose. Under normal growth conditions, 3 [mu]g of mucilage is produced per cell in 30 days. Mucilage production increased 3-4 fold in cells challenged with low phosphate or nitrate conditions. A polyclonal antibody was raised against the mucilage and usedmore » in immunofluorescence studies. These results show that upon contact with another object Closterium aligns itself parallel to that object by a [open quotes]jack-knife[close quotes] motion. Subsequently, large amounts of mucilage are released to form elongate tubes enmeshing the cell with that object. In post-cytokinetic phases of the cell cycle, mucilage is extruded only through the pole of the developing semi-cell. Chlorotetracyclene-labeling of mucilage-secreting cells show a correlation between calcium-rich loci on the cell surface and sites of mucilage release. 20 refs., 25 figs., 1 tab.« less

[Optimization of Polysaccharide Extraction from Spirodela polyrrhiza by Plackett-Burman Design Combined with Box-Behnken Response Surface Methodology].

PubMed

Jiang, Zheng; Wang, Hong; Wu, Qi-nan

2015-06-01

To optimize the processing of polysaccharide extraction from Spirodela polyrrhiza. Five factors related to extraction rate of polysaccharide were optimized by the Plackett-Burman design. Based on this study, three factors, including alcohol volume fraction, extraction temperature and ratio of material to liquid, were regarded as investigation factors by Box-Behnken response surface methodology. The effect order of three factors on the extraction rate of polysaccharide from Spirodela polyrrhiza were as follows: extraction temperature, alcohol volume fraction,ratio of material to liquid. According to Box-Behnken response, the best extraction conditions were: alcohol volume fraction of 81%, ratio of material to liquid of 1:42, extraction temperature of 100 degrees C, extraction time of 60 min for four times. Plackett-Burman design and Box-Behnken response surface methodology used to optimize the extraction process for the polysaccharide in this study is effective and stable.

Modulation of surgical fibrosis by microbial zwitterionic polysaccharides

NASA Astrophysics Data System (ADS)

Ruiz-Perez, Begonia; Chung, Doo R.; Sharpe, Arlene H.; Yagita, Hideo; Kalka-Moll, Wiltrud M.; Sayegh, Mohamed H.; Kasper, Dennis L.; Tzianabos, Arthur O.

2005-11-01

Bacterial carbohydrates have long been considered T cell-independent antigens that primarily induce humoral immune responses. Recently, it has been demonstrated that bacterial capsules that possess a zwitterionic charge motif can activate CD4+ T cells after processing and presentation by antigen-presenting cells. Here we show that these zwitterionic polysaccharides can prevent T helper 1-mediated fibrosis by signaling for the release of IL-10 from CD4+ T cells in vivo. IL-10 production by these T cells and their ability to prevent fibrosis is controlled by the inducible costimulator (ICOS)-ICOS ligand pathway. These data demonstrate that the interaction of the zwitterionic polysaccharides with T cells results in modulation of surgical fibrosis in vivo and suggest a previously undescribed approach to "harnessing" T cell function to prevent inflammatory tissue disorders in humans. IL-10 | microbial polysaccharides | inducible costimulator

Antiproliferative effect of Antrodia camphorata polysaccharides encapsulated in chitosan-silica nanoparticles strongly depends on the metabolic activity type of the cell line

NASA Astrophysics Data System (ADS)

Kong, Zwe-Ling; Chang, Jenq-Sheng; Chang, Ke Liang B.

2013-09-01

Chitosan molecules interact with silica and encapsulate the Antrodia camphorata extract (ACE) polysaccharides to form composite nanoparticles. The nanoparticle suspensions of ACE polysaccharides encapsulated in silica-chitosan and silica nanoparticles approach an average particle size of 210 and 294 nm in solution, respectively. The encapsulation efficiencies of ACE polysaccharides are 66 and 63.5 %, respectively. Scanning electron micrographs confirm the formation of near-spherical nanoparticles. ACE polysaccharides solution had better antioxidative capability than ACE polysaccharides encapsulated in silica or silica-chitosan nanoparticles suspensions. The antioxidant capacity of nanoparticles increases with increasing dissolution time. The antitumor effects of ACE polysaccharides, ACE polysaccharides encapsulated in silica, or silica-chitosan nanoparticles increased with increasing concentration of nanoparticles. This is the first report demonstrating the potential of ACE polysaccharides encapsulated in chitosan-silica nanoparticles for cancer chemoprevention. Furthermore, this study suggests that antiproliferative effect of nanoparticle-encapsulated bioactive could significantly depend on the metabolic activity type of the cell line.

Structural characterization and anticancer activity (MCF7 and MDA-MB-231) of polysaccharides fractionated from brown seaweed Sargassum wightii.

PubMed

Vaikundamoorthy, Ramalingam; Krishnamoorthy, Varunkumar; Vilwanathan, Ravikumar; Rajendran, Rajaram

2018-05-01

The purpose of this study was to investigate the anticancer activity of polysaccharides from brown seaweed Sargassum wightii (SWP) on human breast cancer cells. Initially, two polysaccharide fractions (SWP1 and SWP2) were isolated and purified from the crude polysaccharides using DEAE-52 cellulose and Sephadex G-100 column chromatography. As a result, SWP1 was obtained with the yield of 21.48% was characterized using chemical analysis, GC-MS, 1 H NMR and 13 C NMR. The chemical composition of the extracted polysaccharide contains a neutral polysaccharide with a high total sugar content and low protein, phenol and flavonoid content. GC-MS analysis revealed the presence of galactofuranose and arabinose and NMR spectra shows the presence of β-galactose signals. Anticancer activity shows that the polysaccharides significantly reduce the proliferation of breast cancer cells (MCF7 and MDA-MB-231) in a dose-dependent manner. Further, polysaccharides induced the apoptosis in the breast cancer cells by increasing ROS generation, cleaving mitochondrial membrane and nuclei damage. Finally, polysaccharides increased the activity of caspase 3/9, thus leads to apoptosis of breast cancer. Together, polysaccharides from S. wightii could be a new source of natural anticancer agent against breast cancer with potential value in the manufacturing supplements and drugs. Copyright © 2018 Elsevier B.V. All rights reserved.

Optimization of extraction of polysaccharides from fruiting body of Cordyceps militaris (L.) link using response surface methodology

NASA Astrophysics Data System (ADS)

Nguyen, Hoang Chinh; Thi, Dinh Huynh Mong; Pham, Dinh Chuong

2018-04-01

Polysaccharides from fruiting body of Cordyceps militaris (L.) Link possess various pharmaceutical activities. In this study, polysaccharides from the fruiting body of C. militaris were extracted with different solvents. Of those solvents tested, distilled water was identified as the most efficient solvent for the extraction, resulting in a significant increase in polysaccharides yield. Response surface methodology was then used to optimize the extraction conditions and establish a reliable mathematical model for prediction. A maximum polysaccharides yield of 11.07% was reached at a ratio of water to raw material of 23.2:1 mL/g, an extraction time of 76 min, and a temperature of 93.6°C. This study indicates that the obtained optimal extraction conditions are an efficient method for extraction of polysaccharides from the fruiting body of C. militaris.

Comparative evaluation of Chitosan, Cellulose Acetate, and Polyethersulfone Nanofiber Scaffolds for Neural Differentiation

PubMed Central

Du, Jian; Tan, Elaine; Kim, Hyo Jun; Zhang, Allen; Bhattacharya, Rahul; Yarema, Kevin J

2013-01-01

Based on accumulating evidence that the 3D topography and the chemical features of a growth surface influence neuronal differentiation, we combined these two features by evaluating the cytotoxicity, proliferation, and differentiation of the rat PC12 line and human neural stem cells (hNSCs) on chitosan (CS), cellulose acetate (CA), and polyethersulfone (PES)-derived electrospun nanofibers that had similar diameters, centered in the 200 to 500 nm range. None of the nanofibrous materials were cytotoxic compared to 2D (e.g., flat surface) controls; however, proliferation generally was inhibited on the nanofibrous scaffolds although to a lesser extent on the polysaccharide-derived materials compared to PES. In an exception to the trend towards slower growth on the 3D substrates, hNSCs differentiated on the CS nanofibers proliferated faster than the 2D controls and both cell types showed enhanced indication of neuronal differentiation on the CS scaffolds. Together, these results demonstrate beneficial attributes of CS for neural tissue engineering when this polysaccharide is used in the context of the defined 3D topography found in electrospun nanofibers. PMID:24274534

A polysaccharide fraction of adlay seed (Coixlachryma-jobi L.) induces apoptosis in human non-small cell lung cancer A549 cells

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

Lu, Xiangyi; Liu, Wei; Wu, Junhua

Highlights: Black-Right-Pointing-Pointer A polysaccharide from adlay seed, its molecular mass, optical rotation and sugars was determined. Black-Right-Pointing-Pointer We demonstrated that a polysaccharide from adlay can induce apoptosis in cancer cells. Black-Right-Pointing-Pointer The polysaccharide inhibited the metabolism and proliferation of NSCLC A549 cells. Black-Right-Pointing-Pointer The polysaccharide may trigger apoptosis via the mitochondria-dependent pathway. -- Abstract: Different seed extracts from Coix lachryma-jobi (adlay seed) have been used for the treatment of various cancers in China, and clinical data support the use of these extracts for cancer therapy; however, their underlying molecular mechanisms have not been well defined. A polysaccharide fraction, designated asmore » CP-1, was extracted from the C.lachryma-jobi L. var. using the ethanol subsiding method. CP-1 induced apoptosis in A549 cells in a dose-dependent manner, as determined by MTT assay. Apoptotic bodies were observed in the cells by scanning electronic microscopy. Apoptosis and DNA accumulation during S-phase of the cell cycle were determined by annexin V-FITC and PI staining, respectively, and measured by flow cytometry. CP-1 also extended the comet tail length on single cell gel electrophoresis, and disrupted the mitochondrial membrane potential. Further analysis by western blotting showed that the expression of caspase-3 and caspase-9 proteins was increased. Taken together, our results demonstrate that CP-1 is capable of inhibiting A549 cell proliferation and inducing apoptosis via a mechanism primarily involving the activation of the intrinsic mitochondrial pathway. The assay data suggest that in addition to its nutritional properties, CP-1 is a very promising candidate polysaccharide for the development of anti-cancer medicines.« less

Cell wall proteome of pathogenic fungi.

PubMed

Karkowska-Kuleta, Justyna; Kozik, Andrzej

2015-01-01

A fast development of a wide variety of proteomic techniques supported by mass spectrometry coupled with high performance liquid chromatography has been observed in recent years. It significantly contributes to the progress in research on the cell wall, very important part of the cells of pathogenic fungi. This complicated structure composed of different polysaccharides, proteins, lipids and melanin, plays a key role in interactions with the host during infection. Changes in the set of the surface-exposed proteins under different environmental conditions provide an effective way for pathogens to respond, adapt and survive in the new niches of infection. This work summarizes the current state of knowledge on proteins, studied both qualitatively and quantitatively, and found within the cell wall of fungal pathogens for humans, including Candida albicans, Candida glabrata, Aspergillus fumigatus, Cryptococcus neoformans and other medically important fungi. The described proteomic studies involved the isolation and fractionation of particular sets of proteins of interest with various techniques, often based on differences in their linkages to the polysaccharide scaffold. Furthermore, the proteinaceous contents of extracellular vesicles ("virulence bags") of C. albicans, C. neoformans, Histoplasma capsulatum and Paracoccidioides brasiliensis are compared, because their production can partially explain the problem of non-classical protein secretion by fungi. The role assigned to surface-exposed proteins in pathogenesis of fungal infections is enormously high, thus justifying the need for further investigation of cell wall proteomes.

Stimulatory Effects of Polysaccharide Fraction from Solanum nigrum on RAW 264.7 Murine Macrophage Cells

PubMed Central

Razali, Faizan Naeem; Ismail, Amirah; Abidin, Nurhayati Zainal; Shuib, Adawiyah Suriza

2014-01-01

The polysaccharide fraction from Solanum nigrum Linne has been shown to have antitumor activity by enhancing the CD4+/CD8+ ratio of the T-lymphocyte subpopulation. In this study, we analyzed a polysaccharide extract of S. nigrum to determine its modulating effects on RAW 264.7 murine macrophage cells since macrophages play a key role in inducing both innate and adaptive immune responses. Crude polysaccharide was extracted from the stem of S. nigrum and subjected to ion-exchange chromatography to partially purify the extract. Five polysaccharide fractions were then subjected to a cytotoxicity assay and a nitric oxide production assay. To further analyze the ability of the fractionated polysaccharide extract to activate macrophages, the phagocytosis activity and cytokine production were also measured. The polysaccharide fractions were not cytotoxic, but all of the fractions induced nitric oxide in RAW 264.7 cells. Of the five fractions tested, SN-ppF3 was the least toxic and also induced the greatest amount of nitric oxide, which was comparable to the inducible nitric oxide synthase expression detected in the cell lysate. This fraction also significantly induced phagocytosis activity and stimulated the production of tumor necrosis factor-α and interleukin-6. Our study showed that fraction SN-ppF3 could classically activate macrophages. Macrophage induction may be the manner in which polysaccharides from S. nigrum are able to prevent tumor growth. PMID:25299340

Enzymatic changes in pectic polysaccharides related to the beneficial effect of soaking on bean cooking time.

PubMed

Martínez-Manrique, Enrique; Jacinto-Hernández, Carmen; Garza-García, Ramón; Campos, Albino; Moreno, Ernesto; Bernal-Lugo, Irma

2011-10-01

Cooking time decreases when beans are soaked first. However, the molecular basis of this decrease remains unclear. To determine the mechanisms involved, changes in both pectic polysaccharides and cell wall enzymes were monitored during soaking. Two cultivars and one breeding line were studied. Soaking increased the activity of the cell wall enzymes rhamnogalacturonase, galactanase and polygalacturonase. Their activity in the cell wall was detected as changes in chemical composition of pectic polysaccharides. Rhamnose content decreased but galactose and uronic acid contents increased in the polysaccharides of soaked beans. A decrease in the average molecular weight of the pectin fraction was induced during soaking. The decrease in rhamnose and the polygalacturonase activity were associated (r = 0.933, P = 0.01, and r = 0.725, P = 0.01, respectively) with shorter cooking time after soaking. Pectic cell wall enzymes are responsible for the changes in rhamnogalacturonan I and polygalacturonan induced during soaking and constitute the biochemical factors that give bean cell walls new polysaccharide arrangements. Rhamnogalacturonan I is dispersed throughout the entire cell wall and interacts with cellulose and hemicellulose fibres, resulting in a higher rate of pectic polysaccharide thermosolubility and, therefore, a shorter cooking time. Copyright © 2011 Society of Chemical Industry.

The Specific Nature of Plant Cell Wall Polysaccharides 1

PubMed Central

Nevins, Donald J.; English, Patricia D.; Albersheim, Peter

1967-01-01

Polysaccharide compositions of cell walls were assessed by quantitative analyses of the component sugars. Cell walls were hydrolyzed in 2 n trifluoroacetic acid and the liberated sugars reduced to their respective alditols. The alditols were acetylated and the resulting alditol acetates separated by gas chromatography. Quantitative assay of the alditol acetates was accomplished by electronically integrating the detector output of the gas chromatograph. Myo-inositol, introduced into the sample prior to hydrolysis, served as an internal standard. The cell wall polysaccharide compositions of plant varieties within a given species are essentially identical. However, differences in the sugar composition were observed in cell walls prepared from different species of the same as well as of different genera. The fact that the wall compositions of different varieties of the same species are the same indicates that the biosynthesis of cell wall polysaccharides is genetically regulated. The cell walls of various morphological parts (roots, hypocotyls, first internodes and primary leaves) of bean plants were each found to have a characteristic sugar composition. It was found that the cell wall sugar composition of suspension-cultured sycamore cells could be altered by growing the cells on different carbon sources. This demonstrates that the biosynthesis of cell wall polysaccharides can be manipulated without fatal consequences. PMID:16656594

Biosynthesis of the fungal cell wall polysaccharide galactomannan requires intraluminal GDP-mannose.

PubMed

Engel, Jakob; Schmalhorst, Philipp S; Routier, Françoise H

2012-12-28

Fungal cell walls frequently contain a polymer of mannose and galactose called galactomannan. In the pathogenic filamentous fungus Aspergillus fumigatus, this polysaccharide is made of a linear mannan backbone with side chains of galactofuran and is anchored to the plasma membrane via a glycosylphosphatidylinositol or is covalently linked to the cell wall. To date, the biosynthesis and significance of this polysaccharide are unknown. The present data demonstrate that deletion of the Golgi UDP-galactofuranose transporter GlfB or the GDP-mannose transporter GmtA leads to the absence of galactofuran or galactomannan, respectively. This indicates that the biosynthesis of galactomannan probably occurs in the lumen of the Golgi apparatus and thus contrasts with the biosynthesis of other fungal cell wall polysaccharides studied to date that takes place at the plasma membrane. Transglycosylation of galactomannan from the membrane to the cell wall is hypothesized because both the cell wall-bound and membrane-bound polysaccharide forms are affected in the generated mutants. Considering the severe growth defect of the A. fumigatus GmtA-deficient mutant, proving this paradigm might provide new targets for antifungal therapy.

Isolation, Structural characterization, and antiproliferative activity of phycocolloids from the red seaweed Laurencia papillosa on MCF-7 human breast cancer cells.

PubMed

Ghannam, Ahmed; Murad, Hossam; Jazzara, Marie; Odeh, Adnan; Allaf, Abdul Wahab

2018-03-01

Hydrocolloids from seaweeds (phycocolloids) have interesting functional properties like antiproliferative activity. Marine algae consumptions are linked to law cancer incidences in countries that traditionally consume marine products. In this study, we have investigated water-soluble sulfated polysaccharides isolated from the red seaweed Laurencia papillosa and determined their chemical characteristics and biological activities on the human breast cancer cell line MCF-7. Total polysaccharides were extracted and fractionated from L. papillosa and characterized using FTIR-ATR and NMR spectrometry. In addition, their approximate molar mass was determined by GPC method. The chemical characterization of purified polysaccharides reveals the presence of sulfated polysaccharides differentially dispersed in the algal cell wall. They are the three types of carrageenan, kappa, iota and lambda carrageenans, named LP-W1, -W2 and -W3 respectively. Biological effects and cytotoxicity of the identified of the three sulfated polysaccharide fractions were evaluated in MCF-7 cell line. Our results showed a significant inhibition of MCF-7 cell viability by dose-dependent manner for cells exposed to LP-W2 and LP-W3 polysaccharides for 24h. The mechanistic of LP fractions-mediated apoptosis in MCF-7 cells was demonstrated. The biological effects of L. papillosa SPs indicate that it may be a promising candidate for breast cancer prevention and therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

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

Effect of Urtica dioica agglutinin and Arabidopsis thaliana Chia4 chitinase on the protozoan Phytomonas françai.

PubMed

Gomes Rocha, Graça Celeste; Nicolich, Rebecca; Romeiro, Alexandre; Margis-Pinheiro, Márcia; Attias, Márcia; Alves-Ferreira, Márcio

2003-09-12

The genus Phytomonas is responsible for many diseases in different crop plant species. The finding that chitin is an exposed cell surface polysaccharide in Phytomonas françai and the observation that chitinases can inhibit fungal growth raises expectations about the potential effect of plant chitinases on the P. françai cell membrane surface. The plant chitinases Urtica dioica agglutinin (UDA) and Arabidopsis thaliana Chia4 (ATCHIT4) proteins were over-expressed in bacteria and the interaction between these proteins and P. françai surface was analyzed by immunocytochemistry. We showed that UDA and ATCHIT4 proteins can interact with surface-exposed chitin from P. françai.

Bacterial Polysaccharide Co-Polymerases Share a Common Framework for Control of Polymer Length

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

Tocilj,A.; Munger, C.; Proteau, A.

2008-01-01

The chain length distribution of complex polysaccharides present on the bacterial surface is determined by polysaccharide co-polymerases (PCPs) anchored in the inner membrane. We report crystal structures of the periplasmic domains of three PCPs that impart substantially different chain length distributions to surface polysaccharides. Despite very low sequence similarities, they have a common protomer structure with a long central alpha-helix extending 100 Angstroms into the periplasm. The protomers self-assemble into bell-shaped oligomers of variable sizes, with a large internal cavity. Electron microscopy shows that one of the full-length PCPs has a similar organization as that observed in the crystal formore » its periplasmic domain alone. Functional studies suggest that the top of the PCP oligomers is an important region for determining polysaccharide modal length. These structures provide a detailed view of components of the bacterial polysaccharide assembly machinery.« less

Microengineering neocartilage scaffolds.

PubMed

Petersen, Erik F; Spencer, Richard G S; McFarland, Eric W

2002-06-30

Advances in micropatterning methodologies have made it possible to create structures with precise architecture on the surface of cell culture substrata. We applied these techniques to fabricate microfeatures (15-65 microm wide; 40 microm deep) on the surface of a flexible, biocompatible polysaccharide gel. The micropatterned polymer gels were subsequently applied as scaffolds for chondrocyte culture and proved effective in maintaining key aspects of the chondrogenic phenotype. These were rounded cell morphology and a positive and statistically significant (p < 0.0001) immunofluorescence assay for the production of type II collagen throughout the maximum culture time of 10 days after cell seeding. Further, cells housed within individual surface features were observed to proliferate, while serial application of chondrocytes resulted in the formation of cellular aggregates. These methods represent a novel approach to the problem of engineering reparative cartilage in vitro. Copyright 2002 Wiley Periodicals, Inc.

Interaction of Poly(l-lysine)/Polysaccharide Complex Nanoparticles with Human Vascular Endothelial Cells.

PubMed

Weber, Dominik; Torger, Bernhard; Richter, Karsten; Nessling, Michelle; Momburg, Frank; Woltmann, Beatrice; Müller, Martin; Schwartz-Albiez, Reinhard

2018-05-23

Angiogenesis plays an important role in both soft and hard tissue regeneration, which can be modulated by therapeutic drugs. If nanoparticles (NP) are used as vectors for drug delivery, they have to encounter endothelial cells (EC) lining the vascular lumen, if applied intravenously. Herein the interaction of unloaded polyelectrolyte complex nanoparticles (PECNP) composed of cationic poly(l-lysine) (PLL) and various anionic polysaccharides with human vascular endothelial cells (HUVEC) was analyzed. In particular PECNP were tested for their cell adhesive properties, their cellular uptake and intracellular localization considering composition and net charge. PECNP may form a platform for both cell coating and drug delivery. PECNP, composed of PLL in combination with the polysaccharides dextran sulfate (DS), cellulose sulfate (CS) or heparin (HEP), either unlabeled or labeled with fluorescein isothiocyanate (FITC) and either with positive or negative net charge were prepared. PECNP were applied to human umbilical cord vein endothelial cells (HUVEC) in both, the volume phase and immobilized phase at model substrates like tissue culture dishes. The attachment of PECNP to the cell surface, their intracellular uptake, and effects on cell proliferation and growth behavior were determined. Immobilized PECNP reduced attachment of HUVEC, most prominently the systems PLL/HEP and PLL/DS. A small percentage of immobilized PECNP was taken up by cells during adhesion. PECNP in the volume phase showed no effect of the net charge sign and only minor effects of the composition on the binding and uptake of PECNP at HUVEC. PECNP were stored in endosomal vesicles in a cumulative manner without apparent further processing. During mitosis, internalized PECNP were almost equally distributed among the dividing cells. Both, in the volume phase and immobilized at the surface, PECNP composed of PLL/HEP and PLL/DS clearly reduced cell proliferation of HUVEC, however without an apparent cytotoxic effect, while PLL/CS composition showed minor impairment. PECNP have an anti-adhesive effect on HUVEC and are taken up by endothelial cells which may negatively influence the proliferation rate of HUVEC. The negative effects were less obvious with the composition PLL/CS. Since uptake and binding for PLL/HEP was more efficient than for PLL/DS, PECNP of PLL/HEP may be used to deliver growth factors to endothelial cells during vascularization of bone reconstitution material, whereas those of PLL/CS may have an advantage for substituting biomimetic bone scaffold material.

Structural characterization and anticancer activity of extracellular polysaccharides from ascidian symbiotic bacterium Bacillus thuringiensis.

PubMed

Ramamoorthy, Sathishkumar; Gnanakan, Ananthan; S Lakshmana, Senthil; Meivelu, Moovendhan; Jeganathan, Arun

2018-06-15

In the present study, extracellular polysaccharides (EPS) producing bacterium Bacillus thuringiensis RSK CAS4 was isolated from ascidian Didemnum granulatum and its production was optimized by response surface methodology. Fructose and galactose were found as the major monosaccharides in the EPS from the strain RSK CAS4. Functional groups and structural characteristics of the EPS were characterized with FT-IR and 1 HNMR. The purified EPS showed potent antioxidant properties in investigation against DPPH, hydroxyl, superoxide free radicals. In vitro anticancer activity of purified EPS was evaluated on HEp-2 cells, A549 and Vero cell lines. Growth of cancer cells was inhibited by the EPS in a dose-dependent manner and maximum anticancer activity was found to be 76% against liver cancer at 1000 μg/ml. The antioxidant and anticancer potentials of theEPS from marine bacterium Bacillusthuringiensis RSK CAS4 suggests it as a potential natural source and its scopeas an alternative to synthetics for pharmaceutical application. Copyright © 2018 Elsevier Ltd. All rights reserved.

Surface properties of the conidiospores of Phanerochaete chrysosporium and their relevance to pellet formation.

PubMed Central

Gerin, P A; Dufrene, Y; Bellon-Fontaine, M N; Asther, M; Rouxhet, P G

1993-01-01

The conidiospores of the white rot basidiomycete Phanerochaete chrysosporium tend to aggregate during swelling and germination in agitated liquid medium; as time passes, the initial aggregates tend to associate together and to capture conidiospores that remain isolated. The surface chemical compositions of the conidiospores and of developed hyphae were analyzed by X-ray photoelectron spectroscopy. The data were interpreted by modelling the surface in terms of proteins, polysaccharides and hydrocarbonlike compounds. The surface molecular composition of the dormant conidiospores was estimated to be about 45% proteins, 20% carbohydrates, and 35% hydrocarbonlike compounds. There was an increase in the polysaccharide content during germination. Later, when the hyphae were developed, the polysaccharide content became still higher, and the protein content dropped. The initial step of aggregation is attributed to polysaccharide bridging; its occurrence cannot be explained by a change of the overall hydrophobicity or electrical properties of the conidiospores. Images PMID:8349553

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.

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.

Ultrasound-assisted extraction of water-soluble polysaccharides from the roots of valerian (Valeriana officinalis L.).

PubMed

Hromádková, Z; Ebringerová, A; Valachovic, P

2002-01-01

The insoluble plant residues, obtained after preparation of medicinal tinctures from the roots of valerian (Valeriana officinalis L.) by classical and ultrasound-assisted extraction with aqueous ethanol in a pilot plant, were subsequently treated with hot water to isolate the accessible polysaccharide cell wall components. At almost equal amounts of the hot-water extractable material, the yields of the recovered polysaccharides were lower in the ultrasonical experiment. This is due to the fact that a part of accessible polysaccharides were already solubilised by the aqueous ethanol and recoverable from the medicinal tincture. Therefore, the net yield of extracted polysaccharides was enhanced in the ultrasonical procedure. This fact as well as the sugar composition and structural features of the isolated polysaccharides suggest that ultrasonication have attacked the integrity of cell walls, released and degraded its most accessible polysaccharides (pectic polysaccharides and starch) and increased also the extractibility of its less accessible components--xylan, mannan and glucan. The water-soluble polysaccharide fractions from both the conventional and ultrasonical experiments exhibit significant immunostimulatory activities in mitogenic and comitogenic thymocyte tests.

Saussurea tridactyla Sch. Bip.-derived polysaccharides and flavones reduce oxidative damage in ultraviolet B-irradiated HaCaT cells via a p38MAPK-independent mechanism

PubMed Central

Guo, Yan; Sun, Juan; Ye, Juan; Ma, Wenyu; Yan, Hualing; Wang, Gang

2016-01-01

Objective To investigate whether Saussurea tridactyla Sch. Bip.-derived polysaccharides and flavones exert apoptosis-inhibiting effects in ultraviolet B (UVB)-irradiated HaCaT cells. Methods We divided HaCaT cells into low radiation UVB and high radiation UVB groups. Low radiation UVB and high radiation UVB groups were further divided into a control group, UVB radiation group (UVB group), S. tridactyla Sch. Bip.-derived polysaccharides and flavones low-dose group, and S. tridactyla Sch. Bip.-derived polysaccharides and flavones high-dose group. Cell viability and morphology were assayed by MTT and trypan blue staining. Superoxide dismutase activity, glutathione content, malondialdehyde content, and catalase activity test kits were used to detect superoxide dismutase activity, glutathione content, malondialdehyde content, and catalase activity, respectively. Cell apoptosis, intracellular Ca2+ levels, and mitochondrial membrane potential (Δψ) were detected by flow cytometry. Protein levels were analyzed by Western blotting and immunofluorescence. Results S. tridactyla Sch. Bip.-derived polysaccharides and flavones were found to increase the absorbance of MTT, decrease cell death, alleviate the degree of cell edema, restore the cell morphology, reduce cell death fragments and chip phenomenon, increase superoxide dismutase activity, glutathione content, and catalase activity while decreasing the content of malondialdehyde, lowering the population of apoptotic cells, reducing the intracellular Ca2+ fluorescence, increasing the mitochondrial membrane potential (Δψ), increasing the expressions of p-38, p-53, Bcl-2, and decreasing the expressions of Bax and active-caspase-3. Conclusion S. tridactyla Sch. Bip.-derived polysaccharides and flavones can reduce cell apoptosis to protect HaCaT cells from oxidative damage after UVB irradiation; however, this effect does not occur via the p38MAPK pathway. PMID:26855564

Polysaccharide Hydrogel Combined with Mesenchymal Stem Cells Promotes the Healing of Corneal Alkali Burn in Rats

PubMed Central

Liu, Xun; Yu, Min; Yang, Chunbo; Li, Xiaorong

2015-01-01

Corneal chemical burns are common ophthalmic injuries that may result in permanent visual impairment. Although significant advances have been achieved on the treatment of such cases, the structural and functional restoration of a chemical burn-injured cornea remains challenging. The applications of polysaccharide hydrogel and subconjunctival injection of mesenchymal stem cells (MSCs) have been reported to promote the healing of corneal wounds. In this study, polysaccharide was extracted from Hardy Orchid and mesenchymal stem cells (MSCs) were derived from Sprague-Dawley rats. Supplementation of the polysaccharide significantly enhanced the migration rate of primarily cultured rat corneal epithelial cells. We examined the therapeutic effects of polysaccharide in conjunction with MSCs application on the healing of corneal alkali burns in rats. Compared with either treatment alone, the combination strategy resulted in significantly better recovery of corneal epithelium and reduction in inflammation, neovascularization and opacity of healed cornea. Polysaccharide and MSCs acted additively to increase the expression of anti-inflammatory cytokine (TGF-β), antiangiogenic cytokine (TSP-1) and decrease those promoting inflammation (TNF-α), chemotaxis (MIP-1α and MCP-1) and angiogenesis (VEGF and MMP-2). This study provided evidence that Hardy Orchid derived polysaccharide and MSCs are safe and effective treatments for corneal alkali burns and that their benefits are additive when used in combination. We concluded that combination therapy with polysaccharide and MSCs is a promising clinical treatment for corneal alkali burns and may be applicable for other types of corneal disorder. PMID:25789487

Biosorption of nickel by yeasts in an osmotically unsuitable environment.

PubMed

Breierová, Emilia; Certík, Milan; Kovárová, Annamaria; Gregor, Tomas

2008-01-01

The tolerance, sorption of nickel(II) ions, and changes in the production and composition of exopolymers of eight yeast strains grown under nickel presence with/without NaCl were studied. Strains of Pichia anomala and Candida maltosa known as the most resistant yeasts against nickel tolerated up to 3 mM Ni2+. NaCl addition decreased both the resistance of the yeast strains toward nickel ions and the sorption of metal ions into cells. All yeasts absorbed nickel predominantly into exopolymers (glycoproteins) and on the surface of cells. However, while the amount of polysaccharide moieties of exoglycoproteins of most of the resistant yeasts was induced by stress conditions, the ratio polysaccharide/protein in the exopolymers remained unchanged in the sensitive species Cystofilobasidium. The exopolymer composition might play a key role in yeast adaptation to stress conditions caused by heavy metal ions.

2-Fluoro-L-Fucose Is a Metabolically Incorporated Inhibitor of Plant Cell Wall Polysaccharide Fucosylation

PubMed Central

Wallace, Ian S.

2015-01-01

The monosaccharide L-fucose (L-Fuc) is a common component of plant cell wall polysaccharides and other plant glycans, including the hemicellulose xyloglucan, pectic rhamnogalacturonan-I (RG-I) and rhamnogalacturonan-II (RG-II), arabinogalactan proteins, and N-linked glycans. Mutations compromising the biosynthesis of many plant cell wall polysaccharides are lethal, and as a result, small molecule inhibitors of plant cell wall polysaccharide biosynthesis have been developed because these molecules can be applied at defined concentrations and developmental stages. In this study, we characterize novel small molecule inhibitors of plant fucosylation. 2-fluoro-L-fucose (2F-Fuc) analogs caused severe growth phenotypes when applied to Arabidopsis seedlings, including reduced root growth and altered root morphology. These phenotypic defects were dependent upon the L-Fuc salvage pathway enzyme L-Fucose Kinase/ GDP-L-Fucose Pyrophosphorylase (FKGP), suggesting that 2F-Fuc is metabolically converted to the sugar nucleotide GDP-2F-Fuc, which serves as the active inhibitory molecule. The L-Fuc content of cell wall matrix polysaccharides was reduced in plants treated with 2F-Fuc, suggesting that this molecule inhibits the incorporation of L-Fuc into these polysaccharides. Additionally, phenotypic defects induced by 2F-Fuc treatment could be partially relieved by the exogenous application of boric acid, suggesting that 2F-Fuc inhibits RG-II biosynthesis. Overall, the results presented here suggest that 2F-Fuc is a metabolically incorporated inhibitor of plant cellular fucosylation events, and potentially suggest that other 2-fluorinated monosaccharides could serve as useful chemical probes for the inhibition of cell wall polysaccharide biosynthesis. PMID:26414071

Inhibition of Human Metapneumovirus Binding to Heparan Sulfate Blocks Infection in Human Lung Cells and Airway Tissues

PubMed Central

Klimyte, Edita M.; Smith, Stacy E.; Oreste, Pasqua; Lembo, David

2016-01-01

ABSTRACT Human metapneumovirus (HMPV), a recently discovered paramyxovirus, infects nearly 100% of the world population and causes severe respiratory disease in infants, the elderly, and immunocompromised patients. We previously showed that HMPV binds heparan sulfate proteoglycans (HSPGs) and that HMPV binding requires only the viral fusion (F) protein. To characterize the features of this interaction critical for HMPV binding and the role of this interaction in infection in relevant models, we utilized sulfated polysaccharides, heparan sulfate mimetics, and occluding compounds. Iota-carrageenan demonstrated potent anti-HMPV activity by inhibiting binding to lung cells mediated by the F protein. Furthermore, analysis of a minilibrary of variably sulfated derivatives of Escherichia coli K5 polysaccharide mimicking the HS structure revealed that the highly O-sulfated K5 polysaccharides inhibited HMPV infection, identifying a potential feature of HS critical for HMPV binding. The peptide dendrimer SB105-A10, which binds HS, reduced binding and infection in an F-dependent manner, suggesting that occlusion of HS at the target cell surface is sufficient to prevent infection. HMPV infection was also inhibited by these compounds during apical infection of polarized airway tissues, suggesting that these interactions take place during HMPV infection in a physiologically relevant model. These results reveal key features of the interaction between HMPV and HS, supporting the hypothesis that apical HS in the airway serves as a binding factor during infection, and HS modulating compounds may serve as a platform for potential antiviral development. IMPORTANCE Human metapneumovirus (HMPV) is a paramyxovirus that causes respiratory disease worldwide. It has been previously shown that HMPV requires binding to heparan sulfate on the surfaces of target cells for attachment and infection. In this study, we characterize the key features of this binding interaction using heparan sulfate mimetics, identify an important sulfate modification, and demonstrate that these interactions occur at the apical surface of polarized airway tissues. These findings provide insights into the initial binding step of HMPV infection that has potential for antiviral development. PMID:27489270

Proton beam writing of microstructures in Agar gel for patterned cell growth

NASA Astrophysics Data System (ADS)

Larisch, Wolfgang; Koal, Torsten; Werner, Ronald; Hohlweg, Marcus; Reinert, Tilo; Butz, Tilman

2011-10-01

A rather useful prerequisite for many biological and biophysical studies, e.g., for cell-cell communication or neuronal networks, is confined cell growth on micro-structured surfaces. Solidified Agar layers have smooth surfaces which are electrically neutral and thus inhibit receptor binding and cell adhesion. For the first time, Agar microstructures have been manufactured using proton beam writing (PBW). In the irradiated Agar material the polysaccharides are split into oligosaccharides which can easily be washed off leaving Agar-free areas for cell adhesion. The beam diameter of 1 μm allows the fabrication of compartments accommodating single cells which are connected by micrometer-sized channels. Using the external beam the production process is very fast. Up to 50 Petri dishes can be produced per day which makes this technique very suitable for biological investigations which require large throughputs.

Temperature modulates the cell wall mechanical properties of rice coleoptiles by altering the molecular mass of hemicellulosic polysaccharides

NASA Technical Reports Server (NTRS)

Nakamura, Yukiko; Wakabayashi, Kazuyuki; Hoson, Takayuki

2003-01-01

The present study was conducted to investigate the mechanism inducing the difference in the cell wall extensibility of rice (Oryza sativa L. cv. Koshihikari) coleoptiles grown under various temperature (10-50 degrees C) conditions. The growth rate and the cell wall extensibility of rice coleoptiles exhibited the maximum value at 30-40 degrees C, and became smaller as the growth temperature rose or dropped from this temperature range. The amounts of cell wall polysaccharides per unit length of coleoptile increased in coleoptiles grown at 40 degrees C, but not at other temperature conditions. On the other hand, the molecular size of hemicellulosic polysaccharides was small at temperatures where the cell wall extensibility was high (30-40 degrees C). The autolytic activities of cell walls obtained from coleoptiles grown at 30 and 40 degrees C were substantially higher than those grown at 10, 20 and 50 degrees C. Furthermore, the activities of (1-->3),(1-->4)-beta-glucanases extracted from coleoptile cell walls showed a similar tendency. When oat (1-->3),(1-->4)-beta-glucans with high molecular mass were incubated with the cell wall enzyme preparations from coleoptiles grown at various temperature conditions, the extensive molecular mass downshifts were brought about only by the cell wall enzymes obtained from coleoptiles grown at 30-40 degrees C. There were close correlations between the cell wall extensibility and the molecular mass of hemicellulosic polysaccharides or the activity of beta -glucanases. These results suggest that the environmental temperature regulates the cell wall extensibility of rice coleoptiles by modifying mainly the molecular mass of hemicellulosic polysaccharides. Modulation of the activity of beta-glucanases under various temperature conditions may be involved in the alteration of the molecular size of hemicellulosic polysaccharides.

The Cryoprotectant Effect of Polysaccharides from Plants and Microalgae on Human White Blood Cells.

PubMed

Khudyakov, Andrey Nikolayevich; Polezhaeva, Tatyana Vitalyevna; Zaitseva, Oksana Olegovna; Gűnter, Elena Aleksandrovna; Solomina, Olga Nurzadinovna; Popeyko, Oksana Viktorovna; Shubakov, Anatolyi Aleksandrovich; Vetoshkin, Konstantin Aleksandrovich

2015-08-01

The use of carbohydrates as cryoprotectants is increasing. In this study the effects of incorporating polysaccharides extracted from plants and microalgae originating in northern Russia, into cryoprotectant solutions used to preserve human white blood cells were investigated. Cells in the presence of the polysaccharides were cooled to either -40°C or -80°C, using a two-step cooling process. The morphological and functional indicators of the cryopreserved leukocytes were assessed by light microscopy. When combined with glycerol, the pectin-polysaccharides Lemnan from common duckweed (Lemna minor L.) and Comaruman from marsh cinquefoil (Comarum palustre L), were capable of lowering the freezing point of the cryoprotectant solution and helped to preserve the integrity of the human white blood cell membranes at temperatures below zero. In addition, the increase in phagocytic activity of neutrophils was confirmed. In the context of the contemporary search for effective cell cryoprotectants, the results of this research demonstrate that the cryopreservation of biospecimens in a polysaccharide environment is a promising trend in applied medicine, which can be considered an alternative to traditional cryogenic nitrogen techniques.

Unique phagocytic properties of hemocytes of Pacific oyster Crassostrea gigas against yeast and yeast cell-wall derivatives.

PubMed

Takahashi, Keisuke G; Izumi-Nakajima, Nakako; Mori, Katsuyoshi

2017-11-01

For a marine bivalve mollusk such as Pacific oyster Crassostrea gigas, the elimination of foreign particles via hemocyte phagocytosis plays an important role in host defense mechanisms. The hemocytes of C. gigas have a high phagocytic ability for baker's yeast (Saccharomyces cerevisiae) and its cell-wall product zymosan. C. gigas hemocytes might phagocytose yeast cells after binding to polysaccharides on the cell-wall surface, but it is unknown how and what kinds of polysaccharide molecules are recognized. We conducted experiments to determine differences in the phagocytic ability of C. gigas hemocytes against heat-killed yeast (HK yeast), zymosan and zymocel, which are similarly sized and shaped but differ in the polysaccharide composition of their particle surface. We found that both the agranulocytes and granulocytes exerted strong phagocytic ability on all tested particles. The phagocytic index (PI) of granulocytes for zymosan was 9.4 ± 1.7, which significantly differed with that for HK yeast and zymocel (P < 0.05). To evaluate the PI for the three types of particles, and especially to understand the outcome of the much higher PI for zymosan, PI was gauged in increments of 5 (1-5, 6-10, 11-15, and ≥16), and the phagocytic frequencies were compared according to these increments. The results show that a markedly high PI of ≥16 was exhibited by 18.1% of granulocytes for zymosan, significantly higher than 1.7% and 3.9% shown for HK yeast and zymocel, respectively (P < 0.05). These findings indicate that the relatively high PI for zymosan could not be attributed to a situation wherein all phagocytic hemocytes shared a high mean PI, but rather to the ability of some hemocytes to phagocytose a larger portion of zymosan. To determine whether the phagocytosis of these respective particles depended on the recognition of specific polysaccharide receptors on the hemocyte surface, C. gigas hemocytes were pretreated with soluble α-mannan or β-laminarin and then allowed to phagocytose the three types of the particles. The percentage of phagocytic cells of β-laminarin-treated granulocytes decreased significantly for zymosan and zymocel, but not for yeast. These results suggest that C. gigas might possess at least two types of hemocytes, and that one type of the hemocytes (granulocytes) is more active for phagocytosis. The granulocytes were found to have multiple subtypes with different phagocytic abilities and multiple phagocytic receptors. Some of the granulocyte subtypes revealed a much stronger phagocytic ability, depending on the presence of β-glucan receptors for phagocytosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Surface structure characterization of Aspergillus fumigatus conidia mutated in the melanin synthesis pathway and their human cellular immune response.

PubMed

Bayry, Jagadeesh; Beaussart, Audrey; Dufrêne, Yves F; Sharma, Meenu; Bansal, Kushagra; Kniemeyer, Olaf; Aimanianda, Vishukumar; Brakhage, Axel A; Kaveri, Srini V; Kwon-Chung, Kyung J; Latgé, Jean-Paul; Beauvais, Anne

2014-08-01

In Aspergillus fumigatus, the conidial surface contains dihydroxynaphthalene (DHN)-melanin. Six-clustered gene products have been identified that mediate sequential catalysis of DHN-melanin biosynthesis. Melanin thus produced is known to be a virulence factor, protecting the fungus from the host defense mechanisms. In the present study, individual deletion of the genes involved in the initial three steps of melanin biosynthesis resulted in an altered conidial surface with masked surface rodlet layer, leaky cell wall allowing the deposition of proteins on the cell surface and exposing the otherwise-masked cell wall polysaccharides at the surface. Melanin as such was immunologically inert; however, deletion mutant conidia with modified surfaces could activate human dendritic cells and the subsequent cytokine production in contrast to the wild-type conidia. Cell surface defects were rectified in the conidia mutated in downstream melanin biosynthetic pathway, and maximum immune inertness was observed upon synthesis of vermelone onward. These observations suggest that although melanin as such is an immunologically inert material, it confers virulence by facilitating proper formation of the A. fumigatus conidial surface. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Sulfated Polysaccharides in the Freshwater Green Macroalga Cladophora surera Not Linked to Salinity Adaptation

PubMed Central

Arata, Paula X.; Alberghina, Josefina; Confalonieri, Viviana; Errea, María I.; Estevez, José M.; Ciancia, Marina

2017-01-01

The presence of sulfated polysaccharides in cell walls of seaweeds is considered to be a consequence of the physiological adaptation to the high salinity of the marine environment. Recently, it was found that sulfated polysaccharides were present in certain freshwater Cladophora species and some vascular plants. Cladophora (Ulvophyceae, Chlorophyta) is one of the largest genera of green algae that are able to grow in both, seas and freshwater courses. Previous studies carried out on the water-soluble polysaccharides of the marine species C. falklandica established the presence of sulfated xylogalactoarabinans constituted by a backbone of 4-linked β-L-arabinopyranose units partially sulfated mainly on C3 and also on C2 with partial glycosylation, mostly on C2, with terminal β-D-xylopyranose or β-D-galactofuranose units. Besides, minor amounts of 3-, 6- and/or 3,6-linked β-D-galactan structures, with galactose in the pyranosic form were detected. In this work, the main water soluble cell wall polysaccharides from the freshwater alga Cladophora surera were characterized. It was found that this green alga biosynthesizes sulfated polysaccharides, with a structure similar to those found in marine species of this genus. Calibration of molecular clock with fossil data suggests that colonization of freshwater environments occurred during the Miocene by its ancestor. Therefore, the presence of sulfated polysaccharides in the freshwater green macroalga C. surera could be, in this case, an adaptation to transient desiccation and changes in ionic strength. Retention of sulfated polysaccharides at the cell walls may represent a snapshot of an evolutionary event, and, thus constitutes an excellent model for further studies on the mechanisms of sulfation on cell wall polysaccharides and environmental stress co-evolution. PMID:29181012

Sulfated Polysaccharides in the Freshwater Green Macroalga Cladophora surera Not Linked to Salinity Adaptation.

PubMed

Arata, Paula X; Alberghina, Josefina; Confalonieri, Viviana; Errea, María I; Estevez, José M; Ciancia, Marina

2017-01-01

The presence of sulfated polysaccharides in cell walls of seaweeds is considered to be a consequence of the physiological adaptation to the high salinity of the marine environment. Recently, it was found that sulfated polysaccharides were present in certain freshwater Cladophora species and some vascular plants. Cladophora (Ulvophyceae, Chlorophyta) is one of the largest genera of green algae that are able to grow in both, seas and freshwater courses. Previous studies carried out on the water-soluble polysaccharides of the marine species C. falklandica established the presence of sulfated xylogalactoarabinans constituted by a backbone of 4-linked β-L-arabinopyranose units partially sulfated mainly on C3 and also on C2 with partial glycosylation, mostly on C2, with terminal β-D-xylopyranose or β-D-galactofuranose units. Besides, minor amounts of 3-, 6- and/or 3,6-linked β-D-galactan structures, with galactose in the pyranosic form were detected. In this work, the main water soluble cell wall polysaccharides from the freshwater alga Cladophora surera were characterized. It was found that this green alga biosynthesizes sulfated polysaccharides, with a structure similar to those found in marine species of this genus. Calibration of molecular clock with fossil data suggests that colonization of freshwater environments occurred during the Miocene by its ancestor. Therefore, the presence of sulfated polysaccharides in the freshwater green macroalga C. surera could be, in this case, an adaptation to transient desiccation and changes in ionic strength. Retention of sulfated polysaccharides at the cell walls may represent a snapshot of an evolutionary event, and, thus constitutes an excellent model for further studies on the mechanisms of sulfation on cell wall polysaccharides and environmental stress co-evolution.

Polysaccharide That May Serve as a Carbon and Energy Storage Compound for Sporulation in Bacillus cereus

PubMed Central

Slock, J. A.; Stahly, D. P.

1974-01-01

An intracellular, glucose-containing polysaccharide accumulates in Bacillus cereus early in sporulation and is degraded at the time of spore maturation. This pattern of accumulation and degradation occurred when growth was limited by glucose or a component of yeast extract. These data suggest that the polysaccharide may be serving as a carbon and energy storage compound for sporulation. A somewhat similar pattern of accumulation and degradation of poly-β-hydroxybutyric acid (PHB) was shown earlier by Kominek and Halvorson (1965) to occur in Bacillus cereus. When cells were grown in a medium buffered strongly at pH 7.4, however, very little accumulation of PHB occurred. We have found that polysaccharide accumulates in cells grown in both the strong and weakly buffered media. Perhaps polysaccharide is the major carbon and energy storage compound when cells are grown under conditions preventing significant accumulation of PHB. The lack of polysaccharide accumulation during the exponential phase of growth may be an indication that the needed biosynthetic enzymes are controlled by catabolite repression during growth. The polysaccharide was purified and found to consist of glucose. The iodine absorption spectrum suggests a degree of branching between that of glycogen and amylopectin. PMID:4214355

Neuroprotective effects of ganoderma lucidum polysaccharides against oxidative stress-induced neuronal apoptosis.

PubMed

Sun, Xin-Zhi; Liao, Ying; Li, Wei; Guo, Li-Mei

2017-06-01

Ganoderma lucidum polysaccharides have protective effects against apoptosis in neurons exposed to ischemia/reperfusion injury, but the mechanisms are unclear. The goal of this study was to investigate the underlying mechanisms of the effects of ganoderma lucidum polysaccharides against oxidative stress-induced neuronal apoptosis. Hydrogen peroxide (H 2 O 2 ) was used to induce apoptosis in cultured cerebellar granule cells. In these cells, ganoderma lucidum polysaccharides remarkably suppressed H 2 O 2 -induced apoptosis, decreased expression of caspase-3, Bax and Bim and increased that of Bcl-2. These findings suggested that ganoderma lucidum polysaccharides regulate expression of apoptosis-associated proteins, inhibit oxidative stress-induced neuronal apoptosis and, therefore, have significant neuroprotective effects.

Use of surface plasmon resonance (SPR) to study the dissociation and polysaccharide binding of casein micelles and caseins.

PubMed

Thompson, Abby K; Singh, Harjinder; Dalgleish, Douglas G

2010-11-24

Tests were made to determine whether surface plasmon resonance (SPR) could be used as a technique to study the dissociation properties of bovine casein micelles or of sodium caseinate and the interactions between these protein particles and different polysaccharides. Surfaces of bound micelles or caseinate were made, and the changes in refractive index of these layers were used to define changes in the structures of the chemisorbed material. The technique appears to have some potential for studying details of the dissociation of casein micelles and of the binding of different polysaccharides to caseins.

In vivo anticancer and immunomodulating activities of mannogalactoglucan-type polysaccharides from Lentinus edodes (Berkeley) Singer.

PubMed

Jeff, Iteku Bekomo; Fan, Enxue; Tian, Meihong; Song, Chenyang; Yan, Jingmin; Zhou, Yifa

2016-01-01

There is considerable interest in the potential of mushrooms in modulating the immune system and/or suppressing tumor growth. Among the studied bioactive compounds in mushrooms, polysaccharides are the most important. Nontoxic fungal polysaccharides have a more important role in immunomodulating and antitumor activities which are related to their effects to act of immune effecter cells such as lymphocytes, macrophages, dendritic cells, and natural killer cells involved in the innate and adaptive immunity. Two mannogalactoglucan-type polysaccharides (WPLE-N-2 and WPLE-A0.5-2), purified from the fruiting bodies of Lentinus edodes, were evaluated for their effects on the cellular immune response of Sarcoma 180 (S-180)-bearing mice. Mice were treated with 100 mg/kg body weight of the polysaccharides for 10 days. Significant tumor regressions of the polysaccharide groups' mice were observed compared to the control group. These polysaccharides could induce an increase in nitrite oxide (NO) production in peritoneal macrophages, significantly increase macrophage phagocytosis of tumor-bearing mice and augment concanavalin (ConA) and lipopolysaccharide (LPS)-induced splenocytes proliferation. Our results indicated that immunomodulating activity occurred through host mediation in response to lymphocyte proliferation, macrophage phagocytosis and induction of NO production while the antitumor activity occurred through direct cytotoxicity. Our findings suggest that mannogalactoglucan-type polysaccharides from L. edodes can be explored as novel potential immunostimulants. Our research provides essential data to a better understanding of L. edodes bioactive compounds, especially polysaccharides. Our results also confirm the key role of β-linkages in the antitumor and immunomodulating effects of polysaccharides.

[Effects of germanium on cell growth, polysaccharide production and cellular redox status in suspension cultures of protocorm-like bodies of Dendrobium huoshanense].

PubMed

Wei, Ming; Yang, Chaoying; Jiang, Shaotong

2010-03-01

To solve the problem of low growth rate and metabolism level in suspension cultures of protocorm-like bodies (PLBs) of Dendrobium huoshanense. The effects of germanium on PLB proliferation and accumulation of polysaccharides together with nutrient utilization were investigated and the contents of reducing sugars, soluble proteins, the activities of antioxidant enzymes and redox status of the cells of PLB were analyzed. The results indicated that the optimum concentration of germanium dioxide (4.0 mg/L) significantly enhanced the cell growth and accumulation of polysaccharides, greatly improved contents of reducing sugars and soluble proteins, increased the activities of superoxide dismutase (SOD) and catalase (CAT) but decreased the activity of peroxidase(POD). The cell dry weight and production of polysaccharides were 32.6 g/L and 3.78 g/L, respectively. The analysis of cellular redox status showed that the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) in cells and the activity of glutathione reductase were significantly increased by the addition of germanium dioxide. The suitable concentration of germanium dioxide was beneficial to the cell growth and the accumulation of polysaccharides.

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.

Composition and immunoreactivity of the A60 complex and other cell fractions from Mycobacterium bovis BCG.

PubMed

Cocito, C; Vanlinden, F

1995-02-01

Surface static cultures of Mycobacterium bovis BCG contained cells embedded in an extracellular matrix, whose mechanical removal yielded free cells that were pressure disrupted and fractionated into cytoplasm and walls. Cell envelopes were either mechanically disrupted or extracted with detergents. Intracellular and extracellular fractions were analysed for proteins, polysaccharides, and antigen 6O (A60), a major complex immunodominant in tuberculosis. A60 was present in extracellular matrix, cytoplasm and walls: it represented a substantial portion of the proteins and polysaccharides of these fractions. While the protein/polysaccharide ratio varied according to the origin of A60 preparations, the electrophoretic patterns of A60 proteins (which accounted for the immunogenicity of the complex) remained unchanged. Western blots pointed to the proteins present within the 29-45 kDa range as the A60 components endowed with the highest immunogenicity level. Since the most heavily stained protein bands in SDS-PAGE patterns were located outside the region best recognized by antisera, a striking discordance was found between concentration and immunogenicity patterns of A60 proteins. The electrophoretic patterns of A60- and non-A60-proteins from cytoplasm were also different. A60 complexes in dot blots and some electrophoresed A60 proteins reacted with monoclonal antibodies directed against lipoarabinomannan (LAM), a highly immunogenic polymer of cell envelope. This contaminating compound was removed from A60 with organic solvents and detergents. SDS-PAGE and Western blot patterns of proteins from delipidated A60 were similar to those of native A60 proteins.

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.

Insights into cell wall structure of Sida hermaphrodita and its influence on recalcitrance.

PubMed

Damm, Tatjana; Pattathil, Sivakumar; Günl, Markus; Jablonowski, Nicolai David; O'Neill, Malcolm; Grün, Katharina Susanne; Grande, Philipp Michael; Leitner, Walter; Schurr, Ulrich; Usadel, Björn; Klose, Holger

2017-07-15

The perennial plant Sida hermaphrodita (Sida) is attracting attention as potential energy crop. Here, the first detailed view on non-cellulosic Sida cell wall polysaccharide composition, structure and architecture is given. Cell walls were prepared from Sida stems and sequentially extracted with aqueous buffers and alkali. The structures of the quantitatively predominant polysaccharides present in each fraction were determined by biochemical characterization, glycome profiling and mass spectrometry. The amounts of glucose released by Accellerase-1500 ® treatment of the cell wall and the cell wall residue remaining after each extraction were used to assess the roles of pectin and hemicellulose in the recalcitrance of Sida biomass. 4-O-Methyl glucuronoxylan with a low proportion of side substitutions was identified as the major non-cellulosic glycan component of Sida stem cell walls. Pectic polysaccharides and xylans were found to be associated with lignin, suggesting that these polysaccharides have roles in Sida cell wall recalcitrance to enzymatic hydrolysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

The polysaccharides from fermented Ganoderma lucidum mycelia induced miRNAs regulation in suppressed HepG2 cells.

PubMed

Shen, Jie; Park, Hyeon-soo; Xia, Yong-mei; Kim, Gon-sup; Cui, Steve W

2014-03-15

Medicinal mushroom polysaccharides such as Ganoderma lucidum polysaccharides (GLPs) have been commonly hypothesized to suppress tumor cells proliferation through immune effects. To verify this hypothesis through investigating comprehensive miRNA expression in polysaccharide treated cancer cells, an anticancer mycelia GLP was employed to disclose miRNA differential expression of human hepatocarcinoma cells (HepG2), by using a miRNA microarray assay based on Sanger miR-Base Release 16. The experiment and the analysis result indicates that among the 61 differential expressed miRNAs (p ≤ 0.01), 17 of them were regulated significantly. GLP can inhibit HepG2 cells directly through regulation of hepatocarcinoma genes. A newly found miR-3131 exhibited the strongest upregulation (92-folds, Log2 = 6.53, p = 0.000016). The miRNAs responded synergistically in both hepatocarcinoma and immune-related aspects. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assembly of multilayer microcapsules on CacO3 particles from biocompatible polysaccharides.

PubMed

Zhao, Qinghe; Mao, Zhengwei; Gao, Changyou; Shen, Jiacong

2006-01-01

Multilayer microcapsules were fabricated by layer-by-layer (LbL) assembly of natural polysaccharides onto CaCO3 particles, following with core removal. The micron-sized CaCO3 particles were synthesized by reaction between Ca(NO3)2 and Na2CO3 solutions in the existence of carboxylmethyl cellulose (CMC). The incorporated amount of CMC in the CaCO3 particles was found to be 5.3 wt% by thermogravimetric analysis. Two biocompatible polysaccharides, chitosan and sodium alginate were alternately deposited onto the CaCO3(CMC) templates to obtain hollow microcapsules. Regular oscillation of surface charge as detected by zeta potential demonstrated that the assembly proceeded surely in a LbL manner. The stability of the microcapsules was effectively improved by cross-linking of chitosan with glutaraldehyde. The chemical reaction was verified by infrared spectroscopy. The microcapsules thus fabricated could be spontaneously filled with positively charged low molecular weight substances such as rhodamine 6G and showed good biocompatibility, as detected by in vitro cell culture.

Inhibition on the growth of human MDA-MB-231 breast cancer cells in vitro and tumor growth in a mouse xenograft model by Se-containing polysaccharides from Pyracantha fortuneana.

PubMed

Yuan, Chengfu; Wang, Changdong; Wang, Junjie; Kumar, Vikas; Anwar, Firoz; Xiao, Fangxiang; Mushtaq, Gohar; Liu, Yufei; Kamal, Mohammad Amjad; Yuan, Ding

2016-11-01

Breast cancer is the second cause of cancer-related death among Women. Current therapies for breast cancer have adverse side-effects. Selenium (Se)-containing polysaccharides have multiple health benefits to humans. Pyracantha fortuneana (P. fortuneana) contains rich Se polysaccharides. We hypothesized that Se-containing polysaccharides from P. fortuneana possess anticancer activity on breast cancer via inhibiting growth and inducing apoptosis. This study aimed to assess the anticancer effect of Se-containing polysaccharides from P. fortuneana and the underlying mechanisms. Se-containing polysaccharides were purified. Their properties and monosaccharide compositions were analyzed. Their effects on cell growth, expression of cycle proteins, apoptosis and apoptosis-related protein, and tumor growth in mouse xenograft model were examined. This extract contained 93.7% (w/w) of carbohydrate, 2.1% (w/w) of uronic acid and 3.7μg/g of Se, and was considered as Se-conjugated polysaccharides (Se-PFPs). In vitro studies showed that treatment of triple negative breast cancer (TNBC) MDA-MB-231 cells with Se-PFPs (1) inhibited cell growth dose-dependently by arresting cells at G2 phase via inhibiting CDC25C-CyclinB1/CDC2 pathway; (2) caused apoptosis associated with increased p53, Bax, Puma and Noxa, decreased Bcl2, increased Bax/Bcl2 ratio and increased activities of caspases 3/9, suggesting its effect on p53-mediated cytochrome c-caspase pathway. Treatment of nude mice bearing MDA-MB-231-derived xenograft tumors with Se-PFPs significantly reduced tumor growth without altering body weight, confirming its antitumor activity without toxic side effects. Se-PFPs enhanced doxorubicin cytotoxic effects. It is concluded that Se-containing polysaccharides from P. fortuneana potently inhibit the growth and induce apoptosis of TNBC cells and can be potential anticancer agent for TNBC. Copyright © 2016 Elsevier Inc. All rights reserved.

Disruption of Methicillin-resistant Staphylococcus aureus Biofilms with Enzymatic Therapeutics

DTIC Science & Technology

2015-04-29

polysaccharide matrix and bacteria from the growth surface. α-Amylase, bromelain, and papain caused removal of most of the polysaccharide matrix...biofilm EPS matrix, including polysaccharides , proteins, and bacterial/host DNA [21]. While these enzymes have been utilized clinically since the 1940s...clinically or can easily transition to the clinical setting. These enzymes included an anti- polysaccharide agent, α-amylase, an anti-peptidoglycan agent

Optimization of extraction process by response surface methodology and preliminary structural analysis of polysaccharides from defatted peanut (Arachis hypogaea) cakes.

PubMed

Song, Yi; Du, Bingjian; Zhou, Ting; Han, Bing; Yu, Fei; Yang, Rui; Hu, Xiaosong; Ni, Yuanying; Li, Quanhong

2011-02-01

In this work, response surface methodology was used to determine optimum conditions for extraction of polysaccharides from defatted peanut cake. A central composite design including independent variables, such as extraction temperature (x(1)), extraction time (x(2)), and ethanol concentration (x(3)) was used. Selected response which evaluates the extraction process was polysaccharide yield, and the second-order model obtained for polysaccharide yield revealed coefficient of determination of 97.81%. The independent variable with the largest effect on response was ethanol concentration (x(3)). The optimum extraction conditions were found to be extraction temperature 48.7°C, extraction time 1.52 h, and ethanol concentration of 61.9% (v/v), respectively. Under these conditions, the extraction efficiency of polysaccharide can increase to 25.89%. The results of structural analysis showed that the main composition of defatted peanut cake polysaccharide was α-galactose. 2010 Elsevier Ltd. All rights reserved.

Inhibitory effects of Enteromorpha linza polysaccharide on micronucleus of Allium sativum root cells.

PubMed

Zhang, Zhongshan; Wang, Xiaomei; Li, Jingfen; Liu, Chongbin; Zhang, Quanbin

2016-06-01

In this study, the antimutagenic function of the polysaccharide from Enteromorpha linza with the micronucleus test of Allium sativum root cells induced by sulfur dioxide and ultraviolet was studied. The concentration-effect relation of the two inducers was firstly evaluated. The results showed that an increase of genotoxicity damage was demonstrated and micronuclei frequency induced by sulfur dioxide and ultraviolet displayed dose dependent increases. All the doses of polysaccharide did affect the micronuclei frequency formation compared with the negative control. And also, the significant increase in inhibition rate of micronuclei frequency was observed with the increase of the dose of polysaccharide. It was showed maximum inhibition of micronuclei frequency cells (71.74% and 66.70%) at a concentration of 200g/mL in three experiments. The low molecular weight polysaccharide showed higher inhibition rate than raw polysaccharide at the higher concentration (50g/mL) in the absence of sulfur dioxide and ultraviolet. It was confirmed to be a good mutant inhibitor. Copyright © 2016 Elsevier B.V. All rights reserved.

Polysaccharide based nanogels in the drug delivery system: Application as the carrier of pharmaceutical agents.

PubMed

Debele, Tilahun Ayane; Mekuria, Shewaye Lakew; Tsai, Hsieh-Chih

2016-11-01

Polysaccharide-based nanoparticles have fascinated attention as a vesicle of different pharmaceutical agents due to their unique multi-functional groups in addition to their physicochemical properties, including biocompatibility and biodegradability. The existence of multi-functional groups on the polysaccharide backbone permits facile chemical or biochemical modification to synthesize polysaccharide based nanoparticles with miscellaneous structures. Polysaccharide-based nanogels have high water content, large surface area for multivalent bioconjugation, tunable size, and interior network for the incorporation of different pharmaceutical agents. These unique properties offer great potential for the utilization of polysaccharide-based nanogels in the drug delivery systems. Hence, this review describes chemistry of certain common polysaccharides, several methodologies used to synthesize polysaccharide nanoparticles and primarily focused on the polysaccharide (or polysaccharide derivative) based nanogels as the carrier of pharmaceutical agents. Copyright © 2016 Elsevier B.V. All rights reserved.

Golgi-Mediated Synthesis and Secretion of Matrix Polysaccharides of the Primary Cell Wall of Higher Plants

PubMed Central

Driouich, Azeddine; Follet-Gueye, Marie-Laure; Bernard, Sophie; Kousar, Sumaira; Chevalier, Laurence; Vicré-Gibouin, Maïté; Lerouxel, Olivier

2012-01-01

The Golgi apparatus of eukaryotic cells is known for its central role in the processing, sorting, and transport of proteins to intra- and extra-cellular compartments. In plants, it has the additional task of assembling and exporting the non-cellulosic polysaccharides of the cell wall matrix including pectin and hemicelluloses, which are important for plant development and protection. In this review, we focus on the biosynthesis of complex polysaccharides of the primary cell wall of eudicotyledonous plants. We present and discuss the compartmental organization of the Golgi stacks with regards to complex polysaccharide assembly and secretion using immuno-electron microscopy and specific antibodies recognizing various sugar epitopes. We also discuss the significance of the recently identified Golgi-localized glycosyltransferases responsible for the biosynthesis of xyloglucan (XyG) and pectin. PMID:22639665

Golgi-mediated synthesis and secretion of matrix polysaccharides of the primary cell wall of higher plants.

PubMed

Driouich, Azeddine; Follet-Gueye, Marie-Laure; Bernard, Sophie; Kousar, Sumaira; Chevalier, Laurence; Vicré-Gibouin, Maïté; Lerouxel, Olivier

2012-01-01

The Golgi apparatus of eukaryotic cells is known for its central role in the processing, sorting, and transport of proteins to intra- and extra-cellular compartments. In plants, it has the additional task of assembling and exporting the non-cellulosic polysaccharides of the cell wall matrix including pectin and hemicelluloses, which are important for plant development and protection. In this review, we focus on the biosynthesis of complex polysaccharides of the primary cell wall of eudicotyledonous plants. We present and discuss the compartmental organization of the Golgi stacks with regards to complex polysaccharide assembly and secretion using immuno-electron microscopy and specific antibodies recognizing various sugar epitopes. We also discuss the significance of the recently identified Golgi-localized glycosyltransferases responsible for the biosynthesis of xyloglucan (XyG) and pectin.

Imaging of polysaccharides in the tomato cell wall with Raman microspectroscopy

PubMed Central

2014-01-01

Background The primary cell wall of fruits and vegetables is a structure mainly composed of polysaccharides (pectins, hemicelluloses, cellulose). Polysaccharides are assembled into a network and linked together. It is thought that the percentage of components and of plant cell wall has an important influence on mechanical properties of fruits and vegetables. Results In this study the Raman microspectroscopy technique was introduced to the visualization of the distribution of polysaccharides in cell wall of fruit. The methodology of the sample preparation, the measurement using Raman microscope and multivariate image analysis are discussed. Single band imaging (for preliminary analysis) and multivariate image analysis methods (principal component analysis and multivariate curve resolution) were used for the identification and localization of the components in the primary cell wall. Conclusions Raman microspectroscopy supported by multivariate image analysis methods is useful in distinguishing cellulose and pectins in the cell wall in tomatoes. It presents how the localization of biopolymers was possible with minimally prepared samples. PMID:24917885

Pullulan production by Aureobasidium pullulans grown on ethanol stillage as a nitrogen source.

PubMed

West, T P; Strohfus, B

1996-01-01

Pullulan production by Aureobasidium pullulans strain RP-1 using thin stillage from fuel ethanol production as a nitrogen source was studied in a medium using corn syrup as a carbon source. The use of 1% thin stillage as a nitrogen source instead of ammonium sulphate elevated polysaccharide production by strain RP-1 cells when grown on a concentration of up to 7.5% corn syrup, independent of yeast extract supplementation. Dry weights of cells grown in medium containing ammonium sulphate as the nitrogen source were higher than the stillage-grown cells after 7 days of growth. The viscosity of the polysaccharide on day 7 was higher for cells grown on thin stillage rather than ammonium sulphate as a nitrogen source. The pullulan content of the polysaccharide elaborated by ammonium sulphate-grown cells on day 7 was higher than the pullulan content of polysaccharide produced by stillage-grown cells regardless of whether yeast extract was added to the culture medium.

Bacterial glycobiology: rhamnose-containing cell wall polysaccharides in Gram-positive bacteria

PubMed Central

Mistou, Michel-Yves; Sutcliffe, Iain C.; van Sorge, Nina M.

2016-01-01

The composition of the Gram-positive cell wall is typically described as containing peptidoglycan, proteins and essential secondary cell wall structures called teichoic acids, which comprise approximately half of the cell wall mass. The cell walls of many species within the genera Streptococcus, Enterococcus and Lactococcus contain large amounts of the sugar rhamnose, which is incorporated in cell wall-anchored polysaccharides (CWP) that possibly function as homologues of well-studied wall teichoic acids (WTA). The presence and chemical structure of many rhamnose-containing cell wall polysaccharides (RhaCWP) has sometimes been known for decades. In contrast to WTA, insight into the biosynthesis and functional role of RhaCWP has been lacking. Recent studies in human streptococcal and enterococcal pathogens have highlighted critical roles for these complex polysaccharides in bacterial cell wall architecture and pathogenesis. In this review, we provide an overview of the RhaCWP with regards to their biosynthesis, genetics and biological function in species most relevant to human health. We also briefly discuss how increased knowledge in this field can provide interesting leads for new therapeutic compounds and improve biotechnological applications. PMID:26975195

Bacterial glycobiology: rhamnose-containing cell wall polysaccharides in Gram-positive bacteria.

PubMed

Mistou, Michel-Yves; Sutcliffe, Iain C; van Sorge, Nina M

2016-07-01

The composition of the Gram-positive cell wall is typically described as containing peptidoglycan, proteins and essential secondary cell wall structures called teichoic acids, which comprise approximately half of the cell wall mass. The cell walls of many species within the genera Streptococcus, Enterococcus and Lactococcus contain large amounts of the sugar rhamnose, which is incorporated in cell wall-anchored polysaccharides (CWP) that possibly function as homologues of well-studied wall teichoic acids (WTA). The presence and chemical structure of many rhamnose-containing cell wall polysaccharides (RhaCWP) has sometimes been known for decades. In contrast to WTA, insight into the biosynthesis and functional role of RhaCWP has been lacking. Recent studies in human streptococcal and enterococcal pathogens have highlighted critical roles for these complex polysaccharides in bacterial cell wall architecture and pathogenesis. In this review, we provide an overview of the RhaCWP with regards to their biosynthesis, genetics and biological function in species most relevant to human health. We also briefly discuss how increased knowledge in this field can provide interesting leads for new therapeutic compounds and improve biotechnological applications. © FEMS 2016.

Antitumor activities and immunomodulatory of rice bran polysaccharides and its sulfates in vitro.

PubMed

Wang, Li; Li, Yulin; Zhu, Lidan; Yin, Ran; Wang, Ren; Luo, Xiaohu; Li, Yongfu; Li, Yanan; Chen, Zhengxing

2016-07-01

Polysaccharides purified from rice bran show antitumor activity against tumor cells, yet the mechanism of this action remains poorly understood. To address this issue, our study evaluated the effect of rice bran polysaccharides on mouse melanoma cell line B16, and Raw264.7 macrophages. Rice bran polysaccharides (RBP) failed to inhibit B16 cell growth in vitro. However, Raw264.7 macrophages treated by RBP enhancement of cytotoxic effects. The cytotoxicity was confirmed by the stimulation of nitric oxide (NO) production and tumor necrosis factor-α (TNF-α) secretion on Raw264.7 macrophages in a dose-dependent manner. RBP2, a fraction of RBP, notably enhanced the inhibition of B16 cells and boosted the immunepotentiation effect compared with RBP. To further enhance the inhibition of B16 cell growth, sulfated polysaccharides (SRBP) was derived using the chlorosulfonic acid-pyridine method. SRBP2 was found to suppress B16 cell growth, reduce B16 cell survival and stimulate NO and TNF-α production. However, SRBP2 displayed a cytotoxic effect on Raw264.7 macrophages. These results suggest that the antitumor activity of RBP and RBP2 is mediated mainly through the activation of macrophages. SRBP2 exerts its antitumor activity by inducing apoptosis in tumor cells and the secretion of NO and TNF-α. Copyright © 2016 Elsevier B.V. All rights reserved.

Structural studies of fungal cell-wall polysaccharides from two strains of Talaromyces flavus.

PubMed

Parra, E; Jiménez-Barbero, J; Bernabé, M; Leal, J A; Prieto, A; Gómez-Miranda, B

1994-01-03

The water-soluble cell-wall polysaccharides isolated from strains CBS 352.72 and 310.38 of Talaromyces flavus have been investigated by chemical analyses and NMR studies. Two different skeletons coexist, having the structures: [formula:see text]. The small differences between the polysaccharides isolated from both strains are probably due to slight diminution of branching in strain 352.72, as compared with strain 310.38.

Hyaluronan Tumor Cell Interactions in Prostate Cancer Growth and Survival

DTIC Science & Technology

2009-12-01

is a high molecular weight polyanionic polysaccharide that is increased in more advanced prostate cancers. Tumor cell interaction with this... polysaccharide by specific receptors CD44 and RHAMM promote tumor growth, survival and invasion. Work during the last funding period have further defined the... polysaccharide to its cognate receptors. These peptides inhibit tumor growth both in vitro and in vivo and the residues important for the activity

The Dynamic Characteristics of Silver Nanoparticles in Physiological Fluids: Toxicological Implications

DTIC Science & Technology

2014-11-19

and polysaccharide (Ag-PS) coated silver NM. As inhalation is a common route of exposure, an alveolar macrophage cell model with deposition dosages... polysaccharide -coated (Ag− PS) silver NMs. As inhalation is a common route of exposure, an alveolar macrophage cell model with deposition dosages...bioeffects, we evaluated fluid-specific influences on 25 nm Ag NPs with either a hydrocarbon or polysaccharide coating. Our data demonstrated that

Effect of Aconitum coreanum polysaccharide and its sulphated derivative on the migration of human breast cancer MDA-MB-435s cell.

PubMed

Zhang, Yandong; Wu, Wei; Kang, Lihua; Yu, Dehai; Liu, Chunshui

2017-10-01

Polysaccharides extracted from medicinal plants possess multiple functions. However, the inhibitory capacity of polysaccharides on the metastasis of breast cancer remains unclear. In the present study, we investigated the inhibitory activity of Aconitum coreanum polysaccharide (ACP1) and its sulphated derivative ACP1-s on migratory behaviour of human breast cancer cells MDA-MB-435s and evaluated the underlying molecular mechanism. The data from Transwell assay indicated that ACP1 and ACP1-s caused a significant inhibition of MDA-MB-435s cell migration in vitro. ACP1 and ACP1-s significantly impaired MDA-MB-435s cell migratory behaviour, and the accumulated distance and average velocity of ACP1- and ACP1-s-treated cells were reduced markedly. We also found ACP1 and ACP1-s treatment could affect dynamic remodeling of actin cytoskeleton, and suppress phosphorylation and activation of signalling molecules, attributing to anti-metastatic role of ACP1 and ACP1-s. These findings reveal a novel therapeutic potential of A. coreanum polysaccharide and its sulphated derivative for breast cancer metastasis. Copyright © 2017 Elsevier B.V. All rights reserved.

Size-resolved characterization of the polysaccharidic and proteinaceous components of sea spray aerosol

NASA Astrophysics Data System (ADS)

Aller, Josephine Y.; Radway, JoAnn C.; Kilthau, Wendy P.; Bothe, Dylan W.; Wilson, Theodore W.; Vaillancourt, Robert D.; Quinn, Patricia K.; Coffman, Derek J.; Murray, Benjamin J.; Knopf, Daniel A.

2017-04-01

Dissolved organic polymers released by phytoplankton and bacteria abiologically self-assemble in surface ocean waters into nano-to micro-sized gels containing polysaccharides, proteins, lipids and other components. These gels concentrate in the sea surface microlayer (SML), where they can potentially contribute to sea spray aerosol (SSA). Sea spray is a major source of atmospheric aerosol mass over much of the earth's surface, and knowledge of its properties (including the amount and nature of the organic content), size distributions and fluxes are fundamental for determining its role in atmospheric chemistry and climate. Using a cascade impactor, we collected size-fractionated aerosol particles from ambient air and from freshly generated Sea Sweep SSA in the western North Atlantic Ocean together with biological and chemical characterization of subsurface and SML waters. Spectrophotometric methods were applied to quantify the polysaccharide-containing transparent exopolymer (TEP) and protein-containing Coomassie stainable material (CSM) in these particles and waters. This study demonstrates that both TEP and CSM in surface ocean waters are aerosolized with sea spray with the greatest total TEP associated with particles <180 nm in diameter and >5 000 nm. The higher concentrations of TEP and CSM in particles >5 000 nm most likely reflects collection of microorganism cells and/or fragments. The greater concentration of CSM in larger size particles may also reflect greater stability of proteinaceous gels compared to polysaccharide-rich gels in surface waters and the SML. Both TEP and CSM were measured in the ambient marine air sample with concentrations of 2.1 ± 0.16 μg xanthan gum equivalents (XG eq.) m-3 and 14 ± 1.0 μg bovine serum albumin equivalents (BSA eq.) m-3. TEP in Sea Sweep SSA averaged 4.7 ± 3.1 μg XG eq. m-3 and CSM 8.6 ± 7.3 μg BSA eq. m-3. This work shows the transport of marine biogenic material across the air-sea interface through primary particle emission and the first demonstration of particle size discriminated TEP and CSM characterization of SSA and ambient aerosol under field conditions.

Forage digestibility: the intersection of cell wall lignification and plant tissue anatomy

USDA-ARS?s Scientific Manuscript database

Cellulose and the other polysaccharides present in forage cell walls can be completely degraded by the rumen microflora but only when these polysaccharides have been isolated from the wall and all matrix structures eliminated. Understanding how cell wall component interactions limit microbial degrad...

Injectable In Situ Forming Biodegradable Chitosan-Hyaluronic acid Based Hydrogels for Cartilage Tissue Engineering

PubMed Central

Tan, Huaping; Chu, Constance R.; Payne, Karin; Marra, Kacey G.

2009-01-01

Injectable, biodegradable scaffolds are important biomaterials for tissue engineering and drug delivery. Hydrogels derived from natural polysaccharides are ideal scaffolds as they resemble the extracellular matrices of tissues comprised of various glycosaminoglycans (GAG). Here, we report a new class of biocompatible and biodegradable composite hydrogels derived from water-soluble chitosan and oxidized hyaluronic acid upon mixing, without the addition of a chemical crosslinking agent. The gelation is attributed to the Schiff-base reaction between amino and aldehyde groups of polysaccharide derivatives. In the current work, N-succinyl-chitosan (S-CS) and aldehyde hyaluronic acid (A-HA) were synthesized for preparation of the composite hydrogels. The polysaccharide derivatives and composite hydrogels were characterized by FTIR spectroscopy. The effect of the ratio of S-CS and A-HA on the gelation time, microstructure, surface morphology, equilibrium swelling, compressive modulus, and in vitro degradation of composite hydrogels was examined. The potential of the composite hydrogel as an injectable scaffold was demonstrated by encapsulation of bovine articular chondrocytes within the composite hydrogel matrix in vitro. The results demonstrated that the composite hydrogel supported cell survival and the cells retained chondrocytic morphology. These characteristics provide a potential opportunity to use the injectable, composite hydrogels in tissue engineering applications. PMID:19167750

Dynamics of water solutions of natural polysaccharides by fast field cycling nmr relaxometry

NASA Astrophysics Data System (ADS)

Prusova, Alena; Conte, Pellegrino; Kucerik, Jiri; de Pasquale, Claudio; Alonzo, Giuseppe

2010-05-01

Cryobiology studies the effect of low temperatures on living systems such as microorganisms and plants. In particular, plants growing in cold or frozen environments can survive such extreme conditions due to the cold hardening process. Hardening is a three step process during which, first, translocation of polysaccharides to the plant roots affects water structure in the cell-soil surface. For this reason, increase of cell-membrane permeability and resistance to temperatures from -5°C to -10°C is achieved. In a second step, chemical alteration of cell membrane arises and resistance to temperatures up to -20°C is obtained. The last hardening step consists in the vitrification of the plant tissues which allow plants to survive at temperatures as low as -50°C. Since polysaccharides play a very important role in the initial part of the cold hardening process, it is of paramount importance to study the effect of such natural biopolymers on water structure. Here, we present preliminary data obtained by fast field cycling NMR relaxometry on the effect of hyaluronan (an anionic, non-sulfated glycosaminoglycan) on water structure at different concentrations of the polysaccharide. Although hyaluronan is a polysaccharide found exceptionally in animal, human or bacterial bodies, in the present work it was used as a model "pilot" compound. In fact, it has an unique ability to hold water and it contains both polysaccharide and protein-like acetamido functionalities. For this reason, hyaluronan promotes the future research on other plant biopolymers such as, for instance, starch and other very specific proteins. Results revealed that different water-structure systems surround the molecule of hyaluronan in diluted and semidiluted systems. Namely, at the lowest hyaluronan concentration, three hydration shells can be recognized. The first hydration shell is made by bound water (BW) which is strongly fixed to the hyaluronan surface mainly through electrostatic interactions. A second hydration shell contains water molecules, also recognized as partly-bound (PBW), which are not directly interacting with the hyaluronan chains but with BW. Finally, water molecules, which dynamics is resembling that of the pure and undisturbed water, are indicated either as a bulk water or free water (FW). As hyaluronan concentration is increased the third FW hydration shell is lost and all water molecules are affected by the presence of hyaluronan molecules. This work showed the great potential of FFC-NMR relaxometry in revealing water nature in polysaccharide solutions and the possibility for future applications on complex biological systems. Acknowledgements A.P. gratefully acknowledges a bilateral Erasmus project between Brno University of Technology and University of Palermo which provided grant sustainment for working in Italy. Ministry of Education of the Czech Republic, project MSM 0021630501 is also acknwledged. This work was partially funded by Ce.R.T.A. s.c.r.l. (Centri Regionali per le Tecnologie Alimentari; Italy). Authors kindly acknowledge Dr. Vladimír Velebný (CPN company, Dolní Dobrouč, Czech Republic) for providing of hyaluronan sample.

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.

Structural Studies of Complex Carbohydrates of Plant Cell Walls

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

Darvill, Alan; Hahn, Michael G.; O'Neill, Malcolm A.

Most of the solar energy captured by land plants is converted into the polysaccharides (cellulose, hemicellulose, and pectin) that are the predominant components of the cell wall. These walls, which account for the bulk of plant biomass, have numerous roles in the growth and development of plants. Moreover, these walls have a major impact on human life as they are a renewable source of biomass, a source of diverse commercially useful polymers, a major component of wood, and a source of nutrition for humans and livestock. Thus, understanding the molecular mechanisms that lead to wall assembly and how cell wallsmore » and their component polysaccharides contribute to plant growth and development is essential to improve and extend the productivity and value of plant materials. The proposed research will develop and apply advanced analytical and immunological techniques to study specific changes in the structures and interactions of the hemicellulosic and pectic polysaccharides that occur during differentiation and in response to genetic modification and chemical treatments that affect wall biosynthesis. These new techniques will make it possible to accurately characterize minute amounts of cell wall polysaccharides so that subtle changes in structure that occur in individual cell types can be identified and correlated to the physiological or developmental state of the plant. Successful implementation of this research will reveal fundamental relationships between polysaccharide structure, cell wall architecture, and cell wall functions.« less

Atomic force microscopy of adsorbed proteoglycan mimetic nanoparticles: Toward new glycocalyx-mimetic model surfaces.

PubMed

Hedayati, Mohammadhasan; Kipper, Matt J

2018-06-15

Blood vessels present a dense, non-uniform, polysaccharide-rich layer, called the endothelial glycocalyx. The polysaccharides in the glycocalyx include polyanionic glycosaminoglycans (GAGs). This polysaccharide-rich surface has excellent and unique blood compatibility. We report new methods for preparing and characterizing dense GAG surfaces that can serve as models of the vascular endothelial glycocalyx. The GAG-rich surfaces are prepared by adsorbing heparin or chondroitin sulfate-containing polyelectrolyte complex nanoparticles (PCNs) to chitosan-hyaluronan polyelectrolyte multilayers (PEMs). The surfaces are characterized by PeakForce tapping atomic force microscopy, both in air and in aqueous pH 7.4 buffer, and by PeakForce quantitative nanomechanics (PF-QNM) mode with high spatial resolution. These new surfaces provide access to heparin-rich or chondroitin sulfate-rich coatings that mimic both composition and nanoscale structural features of the vascular endothelial glycocalyx. Copyright © 2018. Published by Elsevier Ltd.

Defective anti-polysaccharide IgG vaccine responses in IgA deficient mice.

PubMed

Furuya, Yoichi; Kirimanjeswara, Girish S; Roberts, Sean; Racine, Rachael; Wilson-Welder, Jennifer; Sanfilippo, Alan M; Salmon, Sharon L; Metzger, Dennis W

2017-09-05

We report that IgA -/- mice exhibit specific defects in IgG antibody responses to various polysaccharide vaccines (Francisella tularensis LPS and Pneumovax), but not protein vaccines such as Fluzone. This defect further included responses to polysaccharide-protein conjugate vaccines (Prevnar and Haemophilus influenzae type b-tetanus toxoid vaccine). In agreement with these findings, IgA -/- mice were protected from pathogen challenge with protein- but not polysaccharide-based vaccines. Interestingly, after immunization with live bacteria, IgA +/+ and IgA -/- mice were both resistant to lethal challenge and their IgG anti-polysaccharide antibody responses were comparable. Immunization with live bacteria, but not purified polysaccharide, induced production of serum B cell-activating factor (BAFF), a cytokine important for IgG class switching; supplementing IgA -/- cell cultures with BAFF enhanced in vitro polyclonal IgG production. Taken together, these findings show that IgA deficiency impairs IgG class switching following vaccination with polysaccharide antigens and that live bacterial immunization can overcome this defect. Since IgA deficient patients also often show defects in antibody responses following immunization with polysaccharide vaccines, our findings could have relevance to the clinical management of this population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Polysaccharides as Bacterial Antiadhesive Agents and "Smart" Constituents for Improved Drug Delivery Systems Against Helicobacter pylori Infection.

PubMed

Menchicchi, Bianca; Hensel, Andreas; Goycoolea, Francisco M

2015-01-01

The standard eradication treatment of the hostile Helicobacter pylori (H. pylori) stomach infection is facing increasing alarming antibiotic resistance worldwide and calls for alternative strategies to the use of antibiotics. One new perspective in this direction is cytoprotective compounds for targeted prevention of the adhesion of the bacteria to the stomach host cell and to inhibit the bacterial cell-cell communication via quorum sensing by specific inhibitors. Bacterial adhesion of H. pylori to the host cells is mainly mediated by carbohydrate-protein interactions. Therefore, the use of polyvalent carbohydrates, (e.g. plant-derived polysaccharides), as potential antiadhesive compounds, seems to be a promising tool to prevent the initial docking of the bacterium to the stomach cells. Polysaccharides are common constituents of daily food, either as starch or as dietary fiber and often also function as excipients for galenic drug-delivery formulations. In addition, polysaccharides with defined pharmacodynamics action against bacterial outer membrane proteins can have potential as therapeutic tools in the treatment of bacterial infections. Some polysaccharides are known to possess antibacterial properties against gram-positive bacteria, others to inhibit bacterial colonization by blocking specific carbohydrate receptors involved in host-bacteria interaction. This mode of action is advocated as alternative antiadhesion therapy. Ongoing research is also seeking for polysaccharide-based nanoformulations with potential for local drug delivery at the stomach as novel H. pylori therapies. These approaches pose challenges concerned with the stability of the nanomaterials in the harsh conditions of the gastric environment and their capacity to adhere to the stomach mucosa. In a global scenario, geographical diversity and social habits, namely lifestyle and dietary factors, influence the prevalence of the H. pylori-associated diseases and their severity. In this context, the exploration of the biological activity of plant-derived products or polysaccharides commonly present in foods is increasingly becoming more and more attractive. This review aims to present the current state-of-the-art on the antiadhesive capacity of different polysaccharide families, on polysaccharide-based nanosystems and the proof-of-concept evidence of their potential use as alternative medicines against H. pylori.

Selenium Polysaccharide SPMP-2a from Pleurotus geesteranus Alleviates H2O2-Induced Oxidative Damage in HaCaT Cells

PubMed Central

Zhou, Cheng; Huang, Shoucheng

2017-01-01

Selenium- (Se-) enriched polysaccharide SPMP-2a was extracted and purified from Pleurotus geesteranus. SPMP-2a is a white flocculent polysaccharide and soluble in water, with a molecular weight of 3.32 × 104 Da. Fourier transform infrared spectroscopy spectral analysis indicated that it belongs to an acid Se polysaccharide with α-D-glucopyranoside bond. The effects of Se polysaccharide SPMP-2a in P. geesteranus against hydrogen peroxide- (H2O2-) induced oxidative damage in human keratinocytes (HaCaT) cells were evaluated further. Reduced cell viability and elevated apoptotic rates in H2O2-treated HaCaT cells were proven by MTT and flow cytometry assays. Hoechst 33342 staining revealed chromatin condensations in the nuclei of HaCaT cells. However, with the addition of SPMP-2a, cell viability improved, nuclear condensation declined, and cell apoptotic rates dropped significantly. Ultrastructural observation consistently revealed that treatments with SPMP-2a reduced the number of swollen and vacuolar mitochondria in the H2O2-treated cells compared with the controls. Furthermore, SPMP-2a increased the superoxide dismutase (SOD) and catalase (CAT) activities and reduced reactive oxygen species (ROS) content. Western blot analysis showed that SPMP-2a treatment effectively increased B-cell lymphoma 2 (Bcl-2) protein expression. Therefore, SPMP-2a could improve cellular antioxidant enzyme activities, reduce ROS levels, and increase Bcl-2 protein expression levels, thereby reducing cell apoptosis and protecting HaCaT cells from H2O2-induced oxidative damage. PMID:28293636

Microtubule heterogeneity of Ornithogalum umbellatum ovary epidermal cells: non-stable cortical microtubules and stable lipotubuloid microtubules.

PubMed

Kwiatkowska, Maria; Stępiński, Dariusz; Polit, Justyna T; Popłońska, Katarzyna; Wojtczak, Agnieszka

2011-01-01

Lipotubuloids, structures containing lipid bodies and microtubules, are described in ovary epidermal cells of Ornithogalum umbellatum. Microtubules of lipotubuloids can be fixed in electron microscope fixative containing only buffered OsO(4) or in glutaraldehyde with OsO(4) post-fixation, or in a mixture of OsO(4) and glutaraldehyde. None of these substances fixes cortical microtubules of ovary epidermis of this plant which is characterized by dynamic longitudinal growth. However, cortical microtubules can be fixed with cold methanol according immunocytological methods with the use of β-tubulin antibodies and fluorescein. The existence of cortical microtubules has also been evidenced by EM observations solely after the use of taxol, microtubule stabilizer, and fixation in a glutaraldehyde/OsO(4) mixture. These microtubules mostly lie transversely, sometimes obliquely, and rarely parallel to the cell axis. Staining, using Ruthenium Red and silver hexamine, has revealed that lipotubuloid microtubules surface is covered with polysaccharides. The presumption has been made that the presence of a polysaccharide layer enhances the stability of lipotubuloid microtubules.

[Effect of spermine on cell growth and polysaccharide production in suspension cultures of protocorm-like bodies from Dendrobium huoshanense].

PubMed

Wei, Ming; Jiang, Shao-Tong; Luo, Jian-Ping

2007-03-01

The effect of outer spermine on cell growth, accumulation of polysaccharides and utilization of nutrient together with the intracellular polyamine contents were investigated in suspension cultures of protocorm-like bodies from Dendrobium huoshanense. The results indicated that spermine at 0.6 mmol/L was the most effective in increasing cell growth and polysaccharide synthesis. The specific growth rate of cell increased from 0.046d(-1) to 0.054d(-1), and the maximum dry weight and polysaccharide production reached 32.4g DW/L and 2.46g/L respectively, which were 1.32-fold and 1.31-fold that of the control on day 30. The titres of intracellular free polyamines were higher in the cultures treated with spermine than that of the control. Invertase and nitrate reductase activities were found to increase significantly in the cultured cells treated with spermine, which was beneficial to the utilization of carbon and nitrogen source.

Isolation by cell-column chromatography of immunoglobulins specific for cell surface carbohydrates

PubMed Central

1977-01-01

A new method of affinity chromatography using glutaraldehyde-fixed cells immobilized on Sephadex beads has been used to isolate immunoglobulins (Ig's) specific for cell surface glycoproteins. Ig's that specifically bound and agglutinated the same cells as those originally fixed on the columns were isolated from nonimmune sera of various species. Periodate treatment of the cell-columns and the free cells destroyed their ability to bind the Ig's, and the binding of the Ig's to untreated cells was inhibited by monosaccharides such as D- galactose and sialic acid. The binding of antibodies directed against cell surfaces obtained by immunizing animals with the same mouse tumor cell lines used on the columns (P388 and EL4) was not inhibited by various saccharides. Surface glycoproteins obtained from the mouse tumor cells by immunoprecipitation with the column-isolated Ig's yielded specific electrophoretic patterns that differed from those obtained using Ig's from the sera of rabbits immunized with the tumor cells. The data suggest that the Ig's isolated by cell-column chromatography were directed against carbohydrates, probably those in terminal positions of the polysaccharide portions of the tumor cell surface glycoproteins. Column-isolated Ig's specific for carbohydrates were also useful in studies of cell interactions in nonmammalian systems including Dictyostelium discoideum and Saccharomyces cerevisiae. The cell-column method appears to be adaptable to the isolation of a variety of molecules in addition to antibodies. PMID:833547

Klebsiella pneumoniae yfiRNB operon affects biofilm formation, polysaccharide production and drug susceptibility.

PubMed

Huertas, Mónica G; Zárate, Lina; Acosta, Iván C; Posada, Leonardo; Cruz, Diana P; Lozano, Marcela; Zambrano, María M

2014-12-01

Klebsiella pneumoniae is an opportunistic pathogen important in hospital-acquired infections, which are complicated by the rise of drug-resistant strains and the capacity of cells to adhere to surfaces and form biofilms. In this work, we carried out an analysis of the genes in the K. pneumoniae yfiRNB operon, previously implicated in biofilm formation. The results indicated that in addition to the previously reported effect on type 3 fimbriae expression, this operon also affected biofilm formation due to changes in cellulose as part of the extracellular matrix. Deletion of yfiR resulted in enhanced biofilm formation and an altered colony phenotype indicative of cellulose overproduction when grown on solid indicator media. Extraction of polysaccharides and treatment with cellulase were consistent with the presence of cellulose in biofilms. The enhanced cellulose production did not, however, correlate with virulence as assessed using a Caenorhabditis elegans assay. In addition, cells bearing mutations in genes of the yfiRNB operon varied with respect to the WT control in terms of susceptibility to the antibiotics amikacin, ciprofloxacin, imipenem and meropenem. These results indicated that the yfiRNB operon is implicated in the production of exopolysaccharides that alter cell surface characteristics and the capacity to form biofilms--a phenotype that does not necessarily correlate with properties related with survival, such as resistance to antibiotics. © 2014 The Authors.

Effect of Content of Sulfate Groups in Seaweed Polysaccharides on Antioxidant Activity and Repair Effect of Subcellular Organelles in Injured HK-2 Cells

PubMed Central

Ma, Xiao-Tao; Sun, Xin-Yuan; Yu, Kai; Gui, Qin

2017-01-01

This study aims to investigate the repair effect of subcellular structure injuries of the HK-2 cells of four degraded seaweed polysaccharides (DSPs), namely, the degraded Porphyra yezoensis, Gracilaria lemaneiformis, Sargassum fusiform, and Undaria pinnatifida polysaccharides. The four DSPs have similar molecular weight, but with different content of sulfate groups (i.e., 17.9%, 13.3%, 8.2%, and 5.5%, resp.). The damaged model was established using 2.8 mmol/L oxalate to injure HK-2 cells, and 60 μg/mL of various DSPs was used to repair the damaged cells. With the increase of sulfate group content in DSPs, the scavenging activity of radicals and their reducing power were all improved. Four kinds of DSPs have repair effect on the subcellular organelles of damaged HK-2 cells. After being repaired by DSPs, the release amount of lactate dehydrogenase was decreased, the integrity of cell membrane and lysosome increased, the Δψm increased, the cell of G1 phase arrest was inhibited, the proportion of S phase increased, and cell apoptotic and necrosis rates were significantly reduced. The greater the content of sulfate group is, the stronger is the repair ability of the polysaccharide. These DSPs, particularly the polysaccharide with higher sulfate group content, may be a potential drug for the prevention and cure of kidney stones. PMID:28785372

Nanomechanics of Yeast Surfaces Revealed by AFM

NASA Astrophysics Data System (ADS)

Dague, Etienne; Beaussart, Audrey; Alsteens, David

Despite the large and well-documented characterization of the microbial cell wall in terms of chemical composition, the determination of the mechanical properties of surface molecules in relation to their function remains a key challenge in cell biology.The emergence of powerful tools allowing molecular manipulations has already revolutionized our understanding of the surface properties of fungal cells. At the frontier between nanophysics and molecular biology, atomic force microscopy (AFM), and more specifically single-molecule force spectroscopy (SMFS), has strongly contributed to our current knowledge of the cell wall organization and nanomechanical properties. However, due to the complexity of the technique, measurements on live cells are still at their infancy.In this chapter, we describe the cell wall composition and recapitulate the principles of AFM as well as the main current methodologies used to perform AFM measurements on live cells, including sample immobilization and tip functionalization.The current status of the progress in probing nanomechanics of the yeast surface is illustrated through three recent breakthrough studies. Determination of the cell wall nanostructure and elasticity is presented through two examples: the mechanical response of mannoproteins from brewing yeasts and elasticity measurements on lacking polysaccharide mutant strains. Additionally, an elegant study on force-induced unfolding and clustering of adhesion proteins located at the cell surface is also presented.

Current findings, future trends, and unsolved problems in studies of medicinal mushrooms.

PubMed

Wasser, Solomon P

2011-03-01

The target of the present review is to draw attention to many critically important unsolved problems in the future development of medicinal mushroom science in the twenty-first century. Special attention is paid to mushroom polysaccharides. Many, if not all, higher Basidiomycetes mushrooms contain biologically active polysaccharides in fruit bodies, cultured mycelium, and cultured broth. The data on mushroom polysaccharides are summarized for approximately 700 species of higher Hetero- and Homobasidiomycetes. The chemical structure of polysaccharides and its connection to antitumor activity, including possible ways of chemical modification, experimental testing and clinical use of antitumor or immunostimulating polysaccharides, and possible mechanisms of their biological action, are discussed. Numerous bioactive polysaccharides or polysaccharide-protein complexes from medicinal mushrooms are described that appear to enhance innate and cell-mediated immune responses and exhibit antitumor activities in animals and humans. Stimulation of host immune defense systems by bioactive polymers from medicinal mushrooms has significant effects on the maturation, differentiation, and proliferation of many kinds of immune cells in the host. Many of these mushroom polymers were reported previously to have immunotherapeutic properties by facilitating growth inhibition and destruction of tumor cells. While the mechanism of their antitumor actions is still not completely understood, stimulation and modulation of key host immune responses by these mushroom polymers appears central. Particularly and most importantly for modern medicine are polysaccharides with antitumor and immunostimulating properties. Several of the mushroom polysaccharide compounds have proceeded through phases I, II, and III clinical trials and are used extensively and successfully in Asia to treat various cancers and other diseases. A total of 126 medicinal functions are thought to be produced by medicinal mushrooms and fungi including antitumor, immunomodulating, antioxidant, radical scavenging, cardiovascular, antihypercholesterolemia, antiviral, antibacterial, antiparasitic, antifungal, detoxification, hepatoprotective, and antidiabetic effects.

Application of Box-Behnken design for ultrasonic-assisted extraction of polysaccharides from Paeonia emodi.

PubMed

Ahmad, Ajaz; Alkharfy, Khalid M; Wani, Tanveer A; Raish, Mohammad

2015-01-01

The objective of the present work was to study the ultrasonic assisted extraction and optimization of polysaccharides from Paeonia emodi and evaluation of its anti-inflammatory response. Specifically, the optimization of polysaccharides was carried out using Box-Behnken statistical experimental design. Response surface methodology (RSM) of three factors (extraction temperature, extraction time and liquid solid ratio) was employed to optimize the percentage yield of the polysaccharides. The experimental data were fitted to quadratic response surface models using multiple regression analysis with high coefficient of determination value (R) of 0.9906. The highest polysaccharide yield (8.69%) as per the Derringer's desirability prediction tool was obtained under the optimal extraction condition (extraction temperature 47.03 °C, extraction time 15.68 min, and liquid solid ratio 1.29 ml/g) with a desirability value of 0.98. These optimized values of tested parameters were validated under similar conditions (n = 6), an average of 8.13 ± 2.08% of polysaccharide yield was obtained in an optimized extraction conditions with 93.55% validity. The anti-inflammatory effect of polysaccharides of P. emodi were studied on carrageenan induced paw edema. In vivo results showed that the P. emodi 200mg/kg of polysaccharide extract exhibited strong potential against inflammatory response induced by 1% suspension of carrageenean in normal saline. Copyright © 2014 Elsevier B.V. All rights reserved.

Turnover of galactans and other cell wall polysaccharides during development of flax plants

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

Gorshkova, T.A.; Chemikosova, S.B.; Lozovaya, V.V.

1997-06-01

We investigated the synthesis and turnover of cell wall polysaccharides of the flax (Linum usitatissimum L.) plant during development of the phloem fibers. One-month-old flax plants were exposed to a 40-min pulse with {sup 14}CO{sub 2} followed by 8-h, 24-h, and 1-month periods of chase with ambient CO{sub 2}, and radioactivity in cell wall sugars was determined in various plant parts. The relative radioactivity of glucose in noncellulosic polysaccharides was the highest compared with all other cell wall sugars immediately after the pulse and decreased substantially during the subsequent chase. The relative radioactivities of the other cell wall sugars changedmore » with differing rates, indicating turnover of specific polysaccharides. Notably, after 1 month of chase there was a marked decrease in the proportional mass and total radioactivity in cell wall galactose, indicating a long-term turnover of the galactans enriched in the fiber-containing tissues. The ratio of radiolabeled xylose to arabinose also increased during the chase, indicating a turnover of arabinose-containing polymers and interconversion to xylose. The pattern of label redistribution differed between organs, indicating that the cell wall turnover processes are tissue- and cell-specific.« less

Effective removal of cadmium ions from a simulated gastrointestinal fluid by Lentinus edodes.

PubMed

Qiao, Xin; Huang, Wen; Bian, Yinbing

2014-12-01

Lentinus edodes, a functional food, was evaluated as a potential antidote for adsorption/removal of cadmium ion from simulated gastrointestinal fluids. An adsorption/removal capacity of 65.12 mg/g was achieved by L. edodes in solutions with a pH ranging from 2.5 to 6.0, while little if any adsorption was observed in solutions with a pH under 2.5. In solutions with pH 6.0, 84% of the cadmium adsorption by L. edodes occurred in the first minute. Scanning electronic microscopic examination showed that the cell wall polysaccharides of L. edodes provided a rough sponge-like surface for effective cadmium adsorption. FTIR indicated that the carboxyl, hydroxyl and -NH groups of the cell wall polysaccharides and proteins were the primary functional groups that chemically bind with cadmium ions. The energy dispersive spectrometry further revealed that cation exchange might be attributed to cadmium biosorption. These results suggested that L. edodes was effective for cadmium detoxication, especially in low concentration.

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.

Harvesting of Scenedesmus obliquus FSP-3 using dispersed ozone flotation.

PubMed

Cheng, Ya-Ling; Juang, Yu-Chuan; Liao, Guan-Yu; Tsai, Pei-Wen; Ho, Shih-Hsin; Yeh, Kuei-Ling; Chen, Chun-Yen; Chang, Jo-Shu; Liu, Jhy-Chern; Chen, Wen-Ming; Lee, Duu-Jong

2011-01-01

The Scenedesmus obliquus FSP-3, a species with excellent potential for CO(2) capture and lipid production, was harvested using dispersed ozone flotation. While air aeration does not, ozone produces effective solid-liquid separation through flotation. Ozone dose applied for sufficient algal flotation is similar to those used in practical drinking waterworks. The algae removal rate, surface charge, and hydrophobicity of algal cells, and fluorescence characteristics and proteins and polysaccharides contents of algogenic organic matter (AOM) were determined during ozonation. Proteins released from tightly bound AOM are essential to modifying the hydrophobicity of bubble surfaces for easy cell attachment and to forming a top froth layer for collecting floating cells. Humic substances in the suspension scavenge dosed ozone that adversely affects ozone flotation efficiency of algal cells. Copyright © 2010 Elsevier Ltd. All rights reserved.

Direct visualization of clay microfabric signatures driving organic matter preservation in fine-grained sediment

NASA Astrophysics Data System (ADS)

Curry, Kenneth J.; Bennett, Richard H.; Mayer, Lawrence M.; Curry, Ann; Abril, Maritza; Biesiot, Patricia M.; Hulbert, Matthew H.

2007-04-01

We employed direct visualization of organic matter (OM) sequestered by microfabric signatures in organo-clay systems to study mechanisms of OM protection. We studied polysaccharides, an abundant class of OM in marine sediments, associated with the nano- and microfabric of clay sediment using a novel application of transmission electron microscopy, histochemical staining (periodic acid-thiosemicarbazide-silver proteinate), and enzymatic digestion techniques. We used two experimental organo-clay sediment environments. First, laboratory-consolidated sediment with 10% chitin (w/w) added was probed for chitin before and after digestion with chitinase. Second, fecal pellets from the polychaete Heteromastus filiformis were used as a natural environment rich in clay and polysaccharides. Sections of this material were probed with silver proteinate for polysaccharides before and after digestion with a mixture of enzymes (amylase, cellulase, chitinase, dextranase, and pectinase). In both environments, chitin or other polysaccharides were found within pores, bridging clay domains, and attached to clay surfaces in undigested samples. Digested samples showed chitin or polysaccharides more closely associated with clay surfaces and in small pores. Our results imply protective roles for both sorption to clay surfaces and encapsulation within clay microfabric signatures.

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.

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.

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.

Plant cell wall engineering: applications in biofuel production and improved human health.

PubMed

Burton, Rachel A; Fincher, Geoffrey B

2014-04-01

Plant cell walls consist largely of cellulose, non-cellulosic polysaccharides and lignin. Concerted attempts are underway to convert wall polysaccharides from crop plant residues into renewable transport fuels and other valuable products, and to exploit the dietary benefits of cereal grain wall polysaccharides in human health. Attempts to improve plant performance for these applications have involved the manipulation of the levels and structures of wall components. Some successes in altering non-cellulosic polysaccharides has been achieved, but it would appear that drastic changes in cellulose are more difficult to engineer. Nevertheless, future prospects for both genetically modified (GM) and non-GM technologies to modify plant cell wall composition and structure remain bright, and will undoubtedly find applications beyond the current focus on human health and biofuel production. Copyright © 2013. Published by Elsevier Ltd.

Affinity of low molecular weight fucoidan for P-selectin triggers its binding to activated human platelets.

PubMed

Bachelet, Laure; Bertholon, Isabelle; Lavigne, Damien; Vassy, Roger; Jandrot-Perrus, Martine; Chaubet, Frédéric; Letourneur, Didier

2009-02-01

P-selectin is an adhesion receptor expressed on activated platelets and endothelial cells. Its natural ligand, P-selectin glycoprotein ligand-1, is expressed on leucocytes and the P-selectin/PSGL-1 interaction is involved in leukocyte rolling. We have compared the interaction of P-selectin with several low molecular weight polysaccharides: fucoidan, heparin and dextran sulfate. Binding assays were obtained from the interaction of the polysaccharides with Sialyl Lewis X and PSGL-1 based constructs onto microtiter plates coated with P-selectin. SELDI TOF mass spectrometry was performed with anionic chips arrays coated with P-selectin in the absence or in the presence of polysaccharides. Kd were obtained from surface plasmon resonance experiments with immobilized P-selectin constructs, polysaccharides being injected in the mobile phase. Human whole blood flow cytometry experiments were performed with fluorescein isothiocyanate labelled polysaccharides with or without platelets activators. The fucoidan prevented P-selectin binding to Sialyl Lewis X with an IC(50) of 20 nM as compared to 400 nM for heparin and <25000 nM for dextran sulfate. It exhibited the highest affinity for immobilized P-selectin with a KD of 1.2 nM, two orders of magnitude greater than the K(D) of the other polysaccharides. Mass spectrometry evidenced the formation of a complex between P-selectin and fucoidan. The intensity of the fucoidan binding to platelets was dependent on the level of platelet activation. Competition between fucoidan and an anti P-selectin antibody demonstrated the specificity of the interaction. Low molecular weight fucoidan is a promising therapeutic agent of natural origin for biomedical applications.

Tuning cell adhesive properties via layer-by-layer assembly of chitosan and alginate

PubMed Central

Silva, Joana M.; García, José R.; Reis, Rui L.; García, Andrés J.; Mano, João F.

2017-01-01

Understanding the mechanisms controlling cell-multilayer film interactions is crucial to the successful engineering of these coatings for biotechnological and biomedical applications. Herein, we present a strategy to tune the cell adhesive properties of multilayers based on marine polysaccharides with and without cross-linking and/or coating with extracellular matrix proteins. Chemical cross-linking of multilayers improved mechanical properties of the coatings but also elicited changes in surface chemistry that alter the adhesion of human umbilical vein endothelial cells. We evaluated a strategy to decouple the mechanical and chemical properties of these films, enabling the transition from cell-adhesive to cell-resistant multilayers. Addition of chitosan/alginate multilayers on top of cross-linked films decreased endothelial cell adhesion, spreading, and proliferation to similar levels as uncross-linked films. Our findings highlight the key role of surface chemistry in cell-multilayer film interactions, and these engineered nanocoatings represent a tunable model of cell adhesive and non-adhesive multilayered films. PMID:28126597

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

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

PubMed

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

1997-11-28

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

Characterization and Antiproliferative Effect of Novel Acid Polysaccharides from the Spent Substrate of Shiitake Culinary-Medicinal Mushroom Lentinus edodes (Agaricomycetes) Cultivation.

PubMed

Zhang, Yong; Liu, Wei; Xu, Chunping; Huang, Wei; He, Peixin

2017-01-01

In this study, a high yield of crude polysaccharide (16.73 ± 0.756%) was extracted from the spent mushroom substrate of Lentinus edodes using a hot alkali extraction method. Two groups of polysaccharides (designated as LSMS-1 and LSMS-2) were obtained from the crude extract by size exclusion chromatography (SEC), and their molecular characteristics were examined by a multiangle laser-light scattering (MALLS) and refractive index detector system. The weight-average molar masses of LSMS-1 and LSMS-2 were determined to be 6.842 × 106 and 2.154 × 106 g/mol, respectively. The SEC/MALLS analysis revealed that the molecular shapes of LSMS-1 and LSMS-2 were sphere-like forms in aqueous solution. Carbohydrate composition analysis using chromatography--mass spectrometry revealed that they were both acid heteropolysaccharides. LSMS-1 comprised mainly glucose and galacturonic acid, whereas LSMS-2 mainly consisted of xylose and glucuronic acid. Fourier transform infrared spectral analysis of the purified fractions revealed typical characteristic polysaccharide groups. In addition, MTT assays with refined polysaccharide doses of 25, 50, 100, 200, and 400 µg/mL suggested that both of the polysaccharide fractions exhibited antiproliferative activity against 6 tested human tumor cell lines in a concentration-dependent manner, and LSMS-2 had better anticancer capacity in vitro than LSMS-1. The inhibition ratio of LSMS-2 against A549 human lung cancer cells, the SGC7901 gastric cancer cell line, MCF-7 breast cancer cells, the U937 histiocytic lymphoma cell line, and the MG-63 human osteosarcoma cell line reached 43.55%, 29.97%, 19.63%, 18.24%, and 17.93%, respectively, at a concentration of 400 µg/mL.

Optical methods for creating delivery systems of chemical compounds to plant roots

NASA Astrophysics Data System (ADS)

Kuznetsov, Pavel E.; Rogacheva, Svetlana M.; Arefeva, Oksana A.; Minin, Dmitryi V.; Tolmachev, Sergey A.; Kupadze, Machammad S.

2004-08-01

Spectrophotometric and fluorescence methods have been used for creation and investigation of various systems of target delivery of chemical compounds to roots of plants. The possibility of using liposomes, incrusted by polysaccharides of the external surface of nitrogen-fixing rizospheric bacteria Azospirillum brasilense SP 245, and nanoparticles incrusted by polysaccharides of wheat roots, as the named systems has been shown. The important role of polysaccharide-polysaccharide interaction in the adsorption processes of bacteria on wheat roots has been demonstrated.

Mushroom Polysaccharides: Chemistry and Antiobesity, Antidiabetes, Anticancer, and Antibiotic Properties in Cells, Rodents, and Humans.

PubMed

Friedman, Mendel

2016-11-29

More than 2000 species of edible and/or medicinal mushrooms have been identified to date, many of which are widely consumed, stimulating much research on their health-promoting properties. These properties are associated with bioactive compounds produced by the mushrooms, including polysaccharides. Although β-glucans (homopolysaccharides) are believed to be the major bioactive polysaccharides of mushrooms, other types of mushroom polysaccharides (heteropolysaccharides) also possess biological properties. Here we survey the chemistry of such health-promoting polysaccharides and their reported antiobesity and antidiabetic properties as well as selected anticarcinogenic, antimicrobial, and antiviral effects that demonstrate their multiple health-promoting potential. The associated antioxidative, anti-inflammatory, and immunomodulating activities in fat cells, rodents, and humans are also discussed. The mechanisms of action involve the gut microbiota, meaning the polysaccharides act as prebiotics in the digestive system. Also covered here are the nutritional, functional food, clinical, and epidemiological studies designed to assess the health-promoting properties of polysaccharides, individually and as blended mixtures, against obesity, diabetes, cancer, and infectious diseases, and suggestions for further research. The collated information and suggested research needs might guide further studies needed for a better understanding of the health-promoting properties of mushroom polysaccharides and enhance their use to help prevent and treat human chronic diseases.

Mushroom Polysaccharides: Chemistry and Antiobesity, Antidiabetes, Anticancer, and Antibiotic Properties in Cells, Rodents, and Humans

PubMed Central

Friedman, Mendel

2016-01-01

More than 2000 species of edible and/or medicinal mushrooms have been identified to date, many of which are widely consumed, stimulating much research on their health-promoting properties. These properties are associated with bioactive compounds produced by the mushrooms, including polysaccharides. Although β-glucans (homopolysaccharides) are believed to be the major bioactive polysaccharides of mushrooms, other types of mushroom polysaccharides (heteropolysaccharides) also possess biological properties. Here we survey the chemistry of such health-promoting polysaccharides and their reported antiobesity and antidiabetic properties as well as selected anticarcinogenic, antimicrobial, and antiviral effects that demonstrate their multiple health-promoting potential. The associated antioxidative, anti-inflammatory, and immunomodulating activities in fat cells, rodents, and humans are also discussed. The mechanisms of action involve the gut microbiota, meaning the polysaccharides act as prebiotics in the digestive system. Also covered here are the nutritional, functional food, clinical, and epidemiological studies designed to assess the health-promoting properties of polysaccharides, individually and as blended mixtures, against obesity, diabetes, cancer, and infectious diseases, and suggestions for further research. The collated information and suggested research needs might guide further studies needed for a better understanding of the health-promoting properties of mushroom polysaccharides and enhance their use to help prevent and treat human chronic diseases. PMID:28231175

Multilayered Polysaccharide Nanofilms for Controlled Delivery of Pentoxifylline and Possible Treatment of Chronic Venous Ulceration.

PubMed

Stana, Jan; Stergar, Janja; Gradišnik, Lidija; Flis, Vojko; Kargl, Rupert; Fröhlich, Eleonore; Stana Kleinschek, Karin; Mohan, Tamilselvan; Maver, Uroš

2017-09-11

Local drug delivery systems made from nontoxic polysaccharide nanofilms have an enormous potential in wound care. A detailed understanding of the structural, surface, physicochemical, and cytotoxic properties of such systems is crucial to design clinically efficacious materials. Herein, we fabricated polysaccharide-based nanofilms onto either a 2D model (SiO 2 and Au sensors) or on nonwoven alginate 3D substrates using an alternating assembly of N,N,N-trimethylchitosan (TMC) and alginic acid (ALG) by a spin-assisted layer-by-layer (LbL) technique. These TMC/ALG multilayered nanofilms are used for a uniform encapsulation and controlled release of pentoxifylline (PTX), a potent anti-inflammatory drug for treatment of the chronic venous ulceration. We show a tailorable film growth and mass, morphology, as well as surface properties (charge, hydrophilicity, porosity) of the assembled nanofilms through control of the coating during the spin-assisted assembly. The uniform distribution of the encapsulated PTX in the TMC/ALG nanofilms is preserved even with when the amount of the incorporated PTX increases. The PTX release mechanism from the model and real systems is studied in detail and is very comparable for both systems. Finally, different cell-based assays illustrated the potential of the TMC/ALG multilayer system in wound care (e.g., treatment chronic venous ulceration) applications, including a decrease of TNF-α secretion, a common indicator of inflammation.

Endothelial glycocalyx: permeability barrier and mechanosensor.

PubMed

Curry, F E; Adamson, R H

2012-04-01

Endothelial cells are covered with a polysaccharide rich layer more than 400 nm thick, mechanical properties of which limit access of circulating plasma components to endothelial cell membranes. The barrier properties of this endothelial surface layer are deduced from the rate of tracer penetration into the layer and the mechanics of red and white cell movement through capillary microvessels. This review compares the mechanosensor and permeability properties of an inner layer (100-150 nm, close to the endothelial membrane) characterized as a quasi-periodic structure which accounts for key aspects of transvascular exchange and vascular permeability with those of the whole endothelial surface layers. We conclude that many of the barrier properties of the whole surface layer are not representative of the primary fiber matrix forming the molecular filter determining transvascular exchange. The differences between the properties of the whole layer and the inner glycocalyx structures likely reflect dynamic aspects of the endothelial surface layer including tracer binding to specific components, synthesis and degradation of key components, activation of signaling pathways in the endothelial cells when components of the surface layer are lost or degraded, and the spatial distribution of adhesion proteins in microdomains of the endothelial cell membrane.

Determination of the cell wall polysaccharide and teichoic acid structures from Lactococcus lactis IL1403.

PubMed

Vinogradov, Evgeny; Sadovskaya, Irina; Courtin, Pascal; Kulakauskas, Saulius; Grard, Thierry; Mahony, Jennifer; van Sinderen, Douwe; Chapot-Chartier, Marie-Pierre

2018-06-15

In the lactic acid bacterium Lactococcus lactis, a cell wall polysaccharide (CWPS) is the bacterial receptor of the majority of infecting bacteriophages. The diversity of CWPS structures between strains explains, at least partially, the narrow host range of lactococcal phages. In the present work, we studied the polysaccharide components of the cell wall of the prototype L. lactis subsp. lactis strain IL1403. We identified a rhamnose-rich complex polysaccharide, carrying a glycerophosphate substitution, as the major component. Its structure was analyzed by 2D NMR spectroscopy, methylation analysis and MALDI-TOF MS and shown to be distinctly different from currently known lactococcal CWPS structures. It contains a linear backbone of repeated α-l-Rha disaccharide subunits, which is irregularly substituted with a trisaccharide occasionally bearing a glycerophosphate group. A poly (glycerol phosphate) teichoic acid, another important carbohydrate component of the IL1403 cell wall, was also isolated and structurally characterized. Copyright © 2018 Elsevier Ltd. All rights reserved.

Aureobasidium pullulans morphology: two adapted polysaccharide stains.

PubMed

Oller, Anna R

2005-12-01

Morphological stages of Aureobasidium pullulans were investigated utilizing different media ingredients and were visualized by bright-field microscopy. A polysaccharide stain was developed to stain chlamydospores, cell walls, hyphae, and conidia, since current staining techniques do not reveal subcellular details to identify fungi, especially those that exhibit polysaccharide secretions.

Chemical characterization, antioxidant, immune-regulating and anticancer activities of a novel bioactive polysaccharide from Chenopodium quinoa seeds.

PubMed

Hu, Yichen; Zhang, Jinming; Zou, Liang; Fu, Chaomei; Li, Peng; Zhao, Gang

2017-06-01

Chenopodium quinoa, a promising nutraceutical cereal, has attracted increasing research interest, yet its polysaccharides remains to get few systematic studies. In this study, we employed orthogonal experimental design to optimize the ultrasound-assisted extraction process for highest yield of C. quinoa polysaccharides. A novel C. quinoa polysaccharide (CQP) fraction with high content and low molecular weight (8852Da) was subsequently purified by column chromatography, constituted by galacturonic acid and glucose monosaccharides. The purified CQP exhibited significantly antioxidant effect against DPPH + and ABTS + , with even higher efficiency than some other reported polysaccharides. Moreover, CQP could promote the RAW264.7 macrophage proliferation, while suppress the nitri oxide production on inflammatory RAW264.7 macrophage in a dose- and time-dependent manner. In view of the pathological correlation of free radical, inflammation and carcinogenesis, the anticancer effect of CQP was further investigated on human liver cancer SMMC 7721 and breast cancer MCF-7 cells. Interestingly, CQP displayed cytotoxicity against cancer cells, while none proliferation inhibition on normal cells. These results suggest that the bioactive polysaccharide from C. quinoa provided the promising potential as a natural antioxidant, immune-regulating and anticancer candidate for food and even drug application. Copyright © 2017 Elsevier B.V. All rights reserved.

Aloe arborescens Polysaccharides: In Vitro Immunomodulation and Potential Cytotoxic Activity.

PubMed

Nazeam, Jilan A; Gad, Haidy A; Esmat, Ahmed; El-Hefnawy, Hala M; Singab, Abdel-Naser B

2017-05-01

Different polysaccharides were isolated from the leaves of Aloe arborescens using the gradient power of hydrogen followed by antitumor and immunomodulatory assay. The total polysaccharide content of different fractions, water-soluble polysaccharide (WAP), acid-soluble polysaccharide (ACP), and alkaline-soluble polysaccharide (ALP), was estimated using a phenol-sulfuric acid spectrophotometric method. WAP possessed a higher content of mannose and glucose than either ACP or ALP. In vitro antitumor activity was investigated in three different cancer cell lines, and in vitro immunomodulatory potential was assessed through phagocytosis and lymphocyte transformation assay. The results showed that WAP and ALP exhibited the most significant cytotoxicity against HepG2 human liver cancer cells, with IC 50 values of 26.14 and 21.46 μg/mL, respectively. In contrast, ALP was able to enhance lymphocyte transformation, whereas WAP had the most potent phagocytic activity. Molecular weight, total sugar and uronic acid content, Fourier transform-infrared analysis, and linkage type of bioactive polysaccharides were investigated. These findings revealed that the potential antitumor activity of the natural agents WAP and ALP was through an immunomodulation mechanism, which verifies the use of the plant as adjuvant supplement for cancer patients suffering immunosuppression during chemotherapy.

Antioxidant and antitumor effects of polysaccharides from the fungus Pleurotus abalonus.

PubMed

Ren, Daoyuan; Jiao, Yadong; Yang, Xingbin; Yuan, Li; Guo, Jianjun; Zhao, Yan

2015-07-25

Dietary supplement of edible Pleurotus abalonus (P. abalonus) rich in fungal polysaccharides is associated with anticancer health benefit. We here isolated the polysaccharides (PAP) from the fruiting bodies of P. abalonus, and evaluated the antiproliferative activity of the polysaccharides in human colorectal carcinoma LoVo cells. HPLC analysis showed that PAP consisted of D-mannose, D-ribose, l-rhamnose, D-glucuronic acid, D-glucose and D-galactose, and their corresponding mole percentages were 3.4%, 1.1%, 1.9%, 1.4%, 87.9% and 4.4%, respectively. PAP was shown to exert a high antioxidant activity in vitro and a dose-dependent antiproliferative effect against LoVo cancer cells. Flow cytometry analysis demonstrated that PAP exhibited a stimulatory effect on apoptosis of LoVo cells, and induced the cell-cycle arrest at the S phase. We also found that PAP could increase the generation of intracellular ROS which was a critical mediator in PAP-induced cell growth inhibition. These findings suggest that PAP may serve as a potential novel dietary agent for human colon cancer chemoprevention. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Structural characters and protecting β-cells of a polysaccharide from flowers of Inula japonica.

PubMed

Zhao, Chunzhi; Diao, Yulin; Wang, Changzhen; Qu, Wensheng; Zhao, Xiunan; Ma, Hao; Shan, Junjie; Sun, Guohui

2017-08-01

Our previous studies found that the crude polysaccharides (IJP) from flowers of Inula japonica exhibited significantly anti-diabetic activity in alloxan or MLD-STZ induced diabetic mice. In this study, we will trace an active polysaccharide from IJP and investigate its physico-chemical property and its protective mechanism on islet cell damage. The result showed that an active polysaccharide (IJP-B-1) was isolated from IJP, its molecular mass was 3.7×10 4 Da. IJP-B-1 was composed of rhamnose, arabinose, xylose, mannose, glucose, galactose and galactocuronic acid. Its major backbone structure was (1→3, 6)-linked-galactose and other branched residues. IJP-B-1 could protect pancreatic cells against STZ impairment at 50μg/mL and scavenge OH and O 2 radicals to decrease reactive oxygen generation in islet-cells in vitro. These results suggested that IJP-B-1 might be useful for protecting β-cells and against oxidative stress as an anti-diabetic candidate drug in future. Copyright © 2017 Elsevier B.V. All rights reserved.

Molecular Interactions at Marine Interfaces

DTIC Science & Technology

1994-09-20

Microbial Attachment and Biofilm Formation 9:00 Michael Sinnott Structure of Extracellular Polysaccharides of Pseudomonas atlantica 9:30 Herb Waite...sit/ i u~ . Direct Measurements of the Intermolecular F~rccs Between Polysaccharide Exopolymers from marine Bacter"a and Solid Substrates Georges...aqueous medium of high ionic strength. Effect of Polysaccharide Surface Structurt on Microbial Attachment and Biofilm Formation David C. White and A

Extraction, purification and anti-proliferative activities of polysaccharides from Lentinus edodes.

PubMed

Zhao, Yong-Ming; Wang, Jin; Wu, Zhi-Gang; Yang, Jian-Ming; Li, Wei; Shen, Li-Xia

2016-12-01

In this study, the enzyme-assisted extraction of polysaccharides from Lentinus edodes (LEPs) was optimized by response surface methodology, and a preliminary characterization of the extracted LEPs and their anti-proliferative activities were investigated. An orthogonal assay was constructed to determine the optimal amounts of cellulase, papain and pectinase, which were 15, 20 and 15g/kg, respectively. Then effects of extraction conditions were evaluated and optimized using a Box-Behnken design. The results showed that the highest polysaccharides yield of 15.65% was achieved with an extraction temperature of 54°C, pH 5.0, enzymatic treatment time of 93min and a liquid/material ratio of 29:1mL/g, which correlated well with the predicted yield of 15.58%. Subsequently, the crude LEPs were further purified by DEAE-cellulose and Sephadex-100 chromatography to obtain two fractions, which were designated as LEP-1 and LEP-2 and their monosaccharide compositions were characterized by GC. Fourier-transform infrared spectra demonstrated that LEP-1 and LEP-2 were distinct from each other regarding their chemical structures. In addition, the LEPs exhibited inhibition of cell proliferation on HCT-116 and HeLa cells in vitro. In summary, this study provides an efficient enzyme-assisted extraction for LEPs, which can be used as natural antitumor agents in the pharmaceutical and functional food industries. Copyright © 2016 Elsevier B.V. All rights reserved.

Modulation of phenotypic and functional maturation of murine dendritic cells (DCs) by purified Achyranthes bidentata polysaccharide (ABP).

PubMed

Zou, Yaxuan; Meng, Jingjuan; Chen, Wenna; Liu, Jingling; Li, Xuan; Li, Weiwei; Lu, Changlong; Shan, Fengping

2011-08-01

There are a large number of interactions at molecular and cellular levels between the plant polysaccharides and immune system. Plant polysaccharides present an interesting effects as immunomodulators, particularly in the induction of the cells both in innate and adaptive immune systems. Activation of DCs could improve antitumoral responses usually diminished in cancer patients, and natural adjuvants provide a possibility of inducing this activation. ABP is a purified polysaccharide isolated from Achyranthes bidentata, a traditional Chinese medicine (TCM). The aim of this study is to investigate modulation of phenotypic and functional maturation of murine DCs by ABP. Both phenotypic and functional activities were assessed with use of conventional scanning electronic microscopy (SEM) for the morphology of the DC, transmitted electron microscopy (TEM) for intracellular lysosomes inside the DC, cellular immunohistochemistry for phagocytosis by the DCs, flow cytometry (FCM) for the changes in key surface molecules, bio-assay for the activity of acidic phosphatases (ACP), and ELISA for the production of pro-inflammatory cytokine IL-12. In fact, we found that purified ABP induced phenotypic maturation revealed by increased expression of CD86, CD40, and MHC II. Functional experiments showed the down-regulation of ACP inside DCs (which occurs when phagocytosis of DCs is decreased, and antigen presentation increased with maturation). Finally, ABP increased the production of IL-12. These data reveal that ABP promotes effective activation of murine DCs. This adjuvant-like activity may have therapeutic applications in clinical settings where immune responses need boosting. It is therefore concluded that ABP can exert positive modulation to murine DCs. Copyright © 2011 Elsevier B.V. All rights reserved.

Polysaccharides from Agaricus bisporus and Agaricus brasiliensis show similarities in their structures and their immunomodulatory effects on human monocytic THP-1 cells

PubMed Central

2011-01-01

Background Mushroom polysaccharides have traditionally been used for the prevention and treatment of a multitude of disorders like infectious illnesses, cancers and various autoimmune diseases. Crude mushroom extracts have been tested without detailed chemical analyses of its polysaccharide content. For the present study we decided to chemically determine the carbohydrate composition of semi-purified extracts from 2 closely related and well known basidiomycete species, i.e. Agaricus bisporus and A. brasiliensis and to study their effects on the innate immune system, in particular on the in vitro induction of pro-inflammatory cytokines, using THP-1 cells. Methods Mushroom polysaccharide extracts were prepared by hot water extraction and precipitation with ethanol. Their composition was analyzed by GC-MS and NMR spectroscopy. PMA activated THP-1 cells were treated with the extracts under different conditions and the production of pro-inflammatory cytokines was evaluated by qPCR. Results Semi-purified polysaccharide extracts of A. bisporus and A. brasiliensis (= blazei) were found to contain (1→6),(1→4)-linked α-glucan, (1→6)-linked β-glucan, and mannogalactan. Their proportions were determined by integration of 1H-NMR signs, and were considerably different for the two species. A. brasiliensis showed a higher content of β-glucan, while A. bisporus presented mannogalactan as its main polysaccharide. The extracts induced a comparable increase of transcription of the pro-inflammatory cytokine genes IL-1β and TNF-α as well as of COX-2 in PMA differentiated THP-1 cells. Pro-inflammatory effects of bacterial LPS in this assay could be reduced significantly by the simultaneous addition of A. brasiliensis extract. Conclusions The polysaccharide preparations from the closely related species A. bisporus and A. brasiliensis show major differences in composition: A. bisporus shows high mannogalactan content whereas A. brasiliensis has mostly β-glucan. Semi-purified polysaccharide extracts from both Agaricus species stimulated the production of pro-inflammatory cytokines and enzymes, while the polysaccharide extract of A. brasiliensis reduced synthesis of these cytokines induced by LPS, suggesting programmable immunomodulation. PMID:21787425

Developmental and Tissue-Specific Structural Alterations of the Cell-Wall Polysaccharides of Arabidopsis thaliana Roots.

PubMed Central

Freshour, G.; Clay, R. P.; Fuller, M. S.; Albersheim, P.; Darvill, A. G.; Hahn, M. G.

1996-01-01

The plant cell wall is a dynamic structure that plays important roles in growth and development and in the interactions of plants with their environment and other organisms. We have used monoclonal antibodies that recognize different carbohydrate epitopes present in plant cell-wall polysaccharides to locate these epitopes in roots of developing Arabidopsis thaliana seedlings. An epitope in the pectic polysaccharide rhamnogalacturonan I is observed in the walls of epidermal and cortical cells in mature parts of the root. This epitope is inserted into the walls in a developmentally regulated manner. Initially, the epitope is observed in atrichoblasts and later appears in trichoblasts and simultaneously in cortical cells. A terminal [alpha]-fucosyl-containing epitope is present in almost all of the cell walls in the root. An arabinosylated (1->6)-[beta]-galactan epitope is also found in all of the cell walls of the root with the exception of lateral root-cap cell walls. It is striking that these three polysaccharide epitopes are not uniformly distributed (or accessible) within the walls of a given cell, nor are these epitopes distributed equally across the two walls laid down by adjacent cells. Our results further suggest that the biosynthesis and differentiation of primary cell walls in plants are precisely regulated in a temporal, spatial, and developmental manner. PMID:12226270

Molecular dynamics simulations reveal the assembly mechanism of polysaccharides in marine aerosols.

PubMed

Sun, Lu; Li, Xin; Hede, Thomas; Tu, Yaoquan; Leck, Caroline; Ågren, Hans

2014-12-21

The high Arctic marine environment has recently detected polymer gels in atmospheric aerosol particles and cloud water originating from the surface microlayer of the open leads within the pack ice area. These polysaccharide molecules are water insoluble but water solvated, highly surface-active and highly hydrated (99% water). In order to add to the understanding and to complement missing laboratory characterization of marine polymer gels we have in this work performed an atomistic study of the assembly process and interfacial properties of polysaccharides. Our study reveals a number of salient features of the microscopic process behind polysaccharide assembly into nanogels. With three- and four-repeating units the polysaccharides assemble into a cluster in 50 ns. The aggregates grow quicker by absorbing one or two polymers each time, depending on the unit length and the type of inter-bridging cation. Although both the hydrophobic and hydrophilic domains are contracted, the latter dominates distinctly upon the contraction of solvent accessible surface areas. The establishment of inter-chain hydrogen-bonds is the key to the assembly while ionic bridges can further promote aggregation. During the assembly of the more bent four-unit polymers, intra-chain hydrogen bonds are significantly diminished by Ca(2+). Meanwhile, the percentage of Ca(2+) acting as an ionic bridge is more eminent, highlighting the significance of Ca(2+) ions for longer-chain polysaccharides. The aggregates are able to enhance surface tension more in the presence of Ca(2+) than in the presence of Na(+) owing to their more compact structure. These conclusions all demonstrate that studies of the present kind provide insight into the self-assembly process and interfacial properties of marine gels. We hope this understanding will keep up the interest in the complex and the fascinating relationship between marine microbiology, atmospheric aerosols, clouds and climate.

Hepatoprotective and inhibiting HBV effects of polysaccharides from roots of Sophora flavescens.

PubMed

Yang, Hua; Zhou, Zhenhua; He, Lifang; Ma, Hao; Qu, Wensheng; Yin, Jiye; Jia, Mengfan; Zhao, Xiunan; Shan, Junjie; Gao, Yueqiu

2018-03-01

Roots of Sophora flavescens is an important herbal medicine for treatment of HBV and hepatic carcinoma in China. Alkaloids in the root were well known for exhibiting good hepato-protective and anti-HBV effects. However, polysaccharides as main components in the root remained unknown. In the studies, we investigated the chemical features and hepatoprotective effects of Sophora flavescens polysaccharides (SFP-100 and its active fractions) with ConA-induced hepatitis mice, human liver LO2 cells and HepG2.2.15 cells. The results showed that SFP-100 was composed of arabinose, glucose, galactose and galacturonic acid, SFP-100-A mainly contained glucose. SFP-100-B and SFP-100-C were acidic polysaccharides. SFP-100 significantly decreased hepatocytes apoptosis, inhibited the infiltration of neutrophils and macrophages into liver, and improved the production of IFN-γ and IL-6 of splenocytes in ConA-induced hepatitis mice. SFP-100 and its two sugar fractions increased LO2 cell proliferation and reduced cell apoptosis induced by ConA. SFP-100, SFP-100-A and SFP-100-C remarkedly inhibited the secretion of HBsAg and HBeAg by HepG2.2.15 cells.These results suggested Sophora flavescens polysaccharides exerts significant hepatoprotective and anti-HBV roles, and further is used for treatment of immune-mediated liver disease in the future. Copyright © 2017. Published by Elsevier B.V.

Long Term Maintenance of Polysaccharide-specific Antibodies by IgM Secreting Cells1

PubMed Central

Foote, Jeremy B.; Mahmoud, Tamer I.; Vale, Andre M.; Kearney, John F.

2011-01-01

Many bacteria-associated polysaccharides induce long-lived antibody responses that protect against pathogenic microorganisms. The maintenance of polysaccharide-specific antibody titers may be due to long-lived plasma cells or ongoing antigen-driven B cell activation due to polysaccharide persistence. BALB/c and VHJ558.3 transgenic (TG) mice respond to α 1→3-dextran (DEX) by generating a peak anti-DEX response at 7 days, followed by maintenance of serum antibody levels for up to 150 days. Analysis of the cellular response to DEX identified a population of short-lived, cyclophosphamide sensitive DEX-specific plasmablasts in the spleen, and a quiescent, cyclophosphamide resistant DEX-specific antibody-secreting population in the bone marrow. BrdU pulse-chase experiments demonstrated the longevity of the DEX-specific antibody-secreting population in the bone marrow. Splenic DEX-specific plasmablasts were located in the red pulp with persisting DEX-associated CD11c+ dendritic cells 90 days after immunization, whereas DEX was not detected in the bone marrow after 28 days. Selective depletion of short-lived DEX-specific plasmablasts and memory B1b B cells using cyclophosphamide and anti-CD20 treatment had a minimal impact on the maintenance of serum anti-DEX antibodies. Collectively, these findings demonstrate that the maintenance of serum polysaccharide-specific antibodies is the result of continuous antigen-driven formation of short-lived plasmablasts in the spleen and a quiescent population of antibody-secreting cells maintained in the bone marrow for a long duration. PMID:22116821

Cell wall proteome analysis of Arabidopsis thaliana mature stems.

PubMed

Duruflé, Harold; Clemente, Hélène San; Balliau, Thierry; Zivy, Michel; Dunand, Christophe; Jamet, Elisabeth

2017-04-01

Plant stems carry flowers necessary for species propagation and need to be adapted to mechanical disturbance and environmental factors. The stem cell walls are different from other organs and can modify their rigidity or viscoelastic properties for the integrity and the robustness required to withstand mechanical impacts and environmental stresses. Plant cell wall is composed of complex polysaccharide networks also containing cell wall proteins (CWPs) crucial to perceive and limit the environmental effects. The CWPs are fundamental players in cell wall remodeling processes, and today, only 86 have been identified from the mature stems of the model plant Arabidopsis thaliana. With a destructive method, this study has enlarged its coverage to 302 CWPs. This new proteome is mainly composed of 27.5% proteins acting on polysaccharides, 16% proteases, 11.6% oxido-reductases, 11% possibly related to lipid metabolism and 11% of proteins with interacting domains with proteins or polysaccharides. Compared to stem cell wall proteomes already available (Brachypodium distachyon, Sacharum officinarum, Linum usitatissimum, Medicago sativa), that of A. thaliana stems has a higher proportion of proteins acting on polysaccharides and of proteases, but a lower proportion of oxido-reductases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Polysaccharide peptide isolated from grass-cultured Ganoderma lucidum induces anti-proliferative and pro-apoptotic effects in the human U251 glioma cell line

PubMed Central

Wang, Chunhua; Lin, Dongmei; Chen, Quan; Lin, Shuqian; Shi, Songsheng; Chen, Chunmei

2018-01-01

The Ganoderma lucidum (G. lucidum) mushroom is one of the most extensively studied functional foods, known for its numerous health benefits, including the inhibition of tumor cell growth. The present study assessed the anti-proliferative and pro-apoptotic activity of a novel G. lucidum polysaccharide peptide (GL-PP) in human glioma U251 cells, which was purified from grass-cultured G. lucidum. GL-PP is a glycopeptide with an average molecular weight of 42,635 Da and a polysaccharide-to-peptide ratio of 88.70:11.30. The polysaccharides were composed of l-arabinose, d-mannose and d-glucose at a molar ratio of 1.329:0.372:2.953 and a total of 17 amino acids were detected. The results of the current study demonstrated that GL-PP significantly inhibited U251 cellular proliferation. The proportion of G0/G1 phase cells and sub-G1 phase cells significantly increased as the concentration of GL-PP increased, as did the activity of caspase-3. These results indicate that GL-PP directly inhibited human glioma U251 proliferation by inducing cell cycle arrest and promoting apoptosis. PMID:29541200

Polysaccharide peptide isolated from grass-cultured Ganoderma lucidum induces anti-proliferative and pro-apoptotic effects in the human U251 glioma cell line.

PubMed

Wang, Chunhua; Lin, Dongmei; Chen, Quan; Lin, Shuqian; Shi, Songsheng; Chen, Chunmei

2018-04-01

The Ganoderma lucidum ( G. lucidum ) mushroom is one of the most extensively studied functional foods, known for its numerous health benefits, including the inhibition of tumor cell growth. The present study assessed the anti-proliferative and pro-apoptotic activity of a novel G. lucidum polysaccharide peptide (GL-PP) in human glioma U251 cells, which was purified from grass-cultured G. lucidum . GL-PP is a glycopeptide with an average molecular weight of 42,635 Da and a polysaccharide-to-peptide ratio of 88.70:11.30. The polysaccharides were composed of l-arabinose, d-mannose and d-glucose at a molar ratio of 1.329:0.372:2.953 and a total of 17 amino acids were detected. The results of the current study demonstrated that GL-PP significantly inhibited U251 cellular proliferation. The proportion of G 0 /G 1 phase cells and sub-G 1 phase cells significantly increased as the concentration of GL-PP increased, as did the activity of caspase-3. These results indicate that GL-PP directly inhibited human glioma U251 proliferation by inducing cell cycle arrest and promoting apoptosis.

A polysaccharide from cultured mycelium of Hericium erinaceus and its anti-chronic atrophic gastritis activity.

PubMed

Wang, Mingxing; Gao, Yang; Xu, Duoduo; Gao, Qipin

2015-11-01

A polysaccharide named EP-1 was found by screening cultured mycelium of Hericium erinaceus, which was extracted and subjected to precipitation with ethanol, hollow-fiber ultrafiltration and ion-exchange chromatography. The polysaccharide has a molecular weight of approximately 3100Da and is composed of glucose, mannose and galactose, thus being a heteroglycan. EP-1 has a backbone of α-d-Glc(1→3) and β-d-Glc(1→3). The β-d-Glc(1→3) and α-d-Gal-(1→3) were regarded as branches attached to the C-4 position. The α-d-Man was regarded as a terminal residue. The anti-CAG activity was evaluated in experimental systems using a cell model for identification. The polysaccharide significantly inhibited the growth of MC cells obtained from human gastric mucosa epithelium (GES-1) cells transformed by MNNG, which were used as a chronic atrophic gastritis cell model. It also interfered with the MC cells by inducing cell cycle arrest. Thus, EP-1 shows potential for the development of new functional foods and drugs. Copyright © 2015. Published by Elsevier B.V.

Loss-of-Function Mutation of REDUCED WALL ACETYLATION2 in Arabidopsis Leads to Reduced Cell Wall Acetylation and Increased Resistance to Botrytis cinerea1[W][OA

PubMed Central

Manabe, Yuzuki; Nafisi, Majse; Verhertbruggen, Yves; Orfila, Caroline; Gille, Sascha; Rautengarten, Carsten; Cherk, Candice; Marcus, Susan E.; Somerville, Shauna; Pauly, Markus; Knox, J. Paul; Sakuragi, Yumiko; Scheller, Henrik Vibe

2011-01-01

Nearly all polysaccharides in plant cell walls are O-acetylated, including the various pectic polysaccharides and the hemicelluloses xylan, mannan, and xyloglucan. However, the enzymes involved in the polysaccharide acetylation have not been identified. While the role of polysaccharide acetylation in vivo is unclear, it is known to reduce biofuel yield from lignocellulosic biomass by the inhibition of microorganisms used for fermentation. We have analyzed four Arabidopsis (Arabidopsis thaliana) homologs of the protein Cas1p known to be involved in polysaccharide O-acetylation in Cryptococcus neoformans. Loss-of-function mutants in one of the genes, designated REDUCED WALL ACETYLATION2 (RWA2), had decreased levels of acetylated cell wall polymers. Cell wall material isolated from mutant leaves and treated with alkali released about 20% lower amounts of acetic acid when compared with the wild type. The same level of acetate deficiency was found in several pectic polymers and in xyloglucan. Thus, the rwa2 mutations affect different polymers to the same extent. There were no obvious morphological or growth differences observed between the wild type and rwa2 mutants. However, both alleles of rwa2 displayed increased tolerance toward the necrotrophic fungal pathogen Botrytis cinerea. PMID:21212300

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.

Protective effect of polysaccharides from Sargassum horneri against oxidative stress in RAW264.7 cells.

PubMed

Wen, Zheng-Shun; Liu, Li-Jia; OuYang, Xiao-Kun; Qu, You-Le; Chen, Yin; Ding, Guo-Fang

2014-07-01

This study was designed to investigate chemical composition and the protective effects of polysaccharides isolated from Sargassum horneri against hydrogen peroxide (H2O2)-induced oxidative injury in RAW264.7 cells. Results showed that isolated polysaccharides (SHSc) and the major fractions (SHS1, SHS0.5) contained sulfate ester, and SHS1 was high fucose-containing sulfated polysaccharide. After preincubation with three isolated polysaccharides, RAW264.7 cells viability were significantly restored and decreased in cellular LDH release (P<0.05). SHS1 and SHS0.5 decreased intracellular ROS level, intracellular NO and malonic dialdehyde (MDA) level (P<0.05), restoring activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) (P<0.05), decreasing inducible nitric oxide synthase (iNOS) (P<0.05). Moreover, preincubation of SHS1 with RAW264.7 cells resulted in the increase of the gene expression level of endogenous antioxidant enzymes such as MnSOD and GSH-Px (P<0.05). These results clearly showed that SHSc and its fractions could attenuate H2O2-induced stress injury in RAW264.7 cells, and a similar efficiency in protecting RAW264.7 cells against H2O2-induced oxidative injury between SHS1 and Vitamin C. Taken together, our findings suggested that SHS1 can effectively protect RAW264.7 cells against oxidative stress by H2O2, which might be used as a potential natural antioxidant in the functional food and pharmaceutical industries. Copyright © 2014 Elsevier B.V. All rights reserved.

Inter-serotype comparison of polysaccharides produced by extracellular enzymes from Streptococcus mutans.

PubMed

Yakushiji, T; Inoue, M; Koga, T

1984-04-15

The biochemical and morphological characteristics of polysaccharides synthesized from sucrose by extracellular enzymes from D-glucose-grown Streptococcus mutans representing serotypes a-g were compared. The polysaccharides synthesized by the enzymes from serotypes a, d, and g formed visible aggregates and firmly adhered to glass surfaces, whereas those formed by the enzymes from serotypes b, c, e, and f floated homogeneously and were poorly adherent. The enzymes of serotypes a, d, and g produced large amounts of water-insoluble polysaccharides (IPs, D-glucans), and those of serotypes b, c, e, and f water-soluble polysaccharides (SPs, D-glucans and D- fructans ). As compared with the IPs of serotypes b, c, e, and f, the IPs of serotypes a, d, and g (a) contained a higher proportion of (1----3)-alpha-D-glucosidic linkages and alpha-D-(1----3,6) branch linkages; (b) showed higher susceptibility to (1----3)-alpha-D-glucanase (serotype a excepted) and lower (1----6)-alpha-D-glucanase sensitivity; (c) contained larger amounts of high-molecular-weight fractions; (d) showed higher intrinsic viscosities (serotype b excepted); and (e) had lower S. mutans cell-agglutination activities. On electron-microscope observation, the IPs of all serotypes showed two fibrillar components; a double-stranded fibril, with short, fluffy protrusions extending out of its periphery, and a fine, single-stranded fibril. Thus, the serotypes could be divided into two major groups: a, d, and g; and b, c, e, and f. No similar grouping of serotypes was indicated by the chemical and morphological properties of SPs.

Salmonella enterica Serovar Enteritidis Core O Polysaccharide Conjugated to H:g,m Flagellin as a Candidate Vaccine for Protection against Invasive Infection with S. Enteritidis▿†

PubMed Central

Simon, Raphael; Tennant, Sharon M.; Wang, Jin Y.; Schmidlein, Patrick J.; Lees, Andrew; Ernst, Robert K.; Pasetti, Marcela F.; Galen, James E.; Levine, Myron M.

2011-01-01

Nontyphoidal Salmonella enterica serovars Enteritidis and Typhimurium are a common cause of gastroenteritis but also cause invasive infections and enteric fever in certain hosts (young children in sub-Saharan Africa, the elderly, and immunocompromised individuals). Salmonella O polysaccharides (OPS) and flagellar proteins are virulence factors and protective antigens. The surface polysaccharides of Salmonella are poorly immunogenic and do not confer immunologic memory, limitations overcome by covalently attaching them to carrier proteins. We conjugated core polysaccharide-OPS (COPS) of Salmonella Enteritidis lipopolysaccharide (LPS) to flagellin protein from the homologous strain. COPS and flagellin were purified from a genetically attenuated (ΔguaBA) “reagent strain” (derived from an isolate from a patient with clinical bacteremia) engineered for increased flagellin production (ΔclpPX). Conjugates were constructed by linking flagellin monomers or polymers at random COPS hydroxyls with various polysaccharide/protein ratios by 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) or at the 3-deoxy-d-manno-octulosonic acid (KDO) terminus by thioether chemistry. Mice immunized on days 0, 28, and 56 with COPS-flagellin conjugates mounted higher anti-LPS IgG levels than mice receiving unconjugated COPS and exhibited high antiflagellin IgG; anti-LPS and antiflagellin IgG levels increased following booster doses. Antibodies generated by COPS-flagellin conjugates mediated opsonophagocytosis of S. Enteritidis cells into mouse macrophages. Mice immunized with flagellin alone, COPS-CRM197, or COPS-flagellin conjugates were significantly protected from lethal challenge with wild-type S. Enteritidis (80 to 100% vaccine efficacy). PMID:21807909

Improvement of antioxidant and moisture-preserving activities of Sargassum horneri polysaccharide enzymatic hydrolyzates.

PubMed

Shao, Ping; Chen, Xiaoxiao; Sun, Peilong

2015-03-01

In the previous study, we have found that polysaccharides isolated from Sargassum horneri exhibited bioactivities. The aim of this study was to investigate the antioxidant and moisture-preserving activities of molecular weight alteration of Sargassum horneri polysaccharide in vitro. For this purpose, the homogeneous active polysaccharide SHP was isolated from Sargassum horneri, and response surface methodology was employed to optimize the enzymatic degradation conditions to get SHP-derived fragments with different molecular weight. Results proved that the polysaccharide is capable of scavenging both ABTS and DPPH radicals in vitro. The study revealed that the polysaccharides had strong moisture-absorption and -retention capacities as compared to propanediol and glycerin. Furthermore, these data demonstrated that molecular weight had a certain effect on antioxidant activities and strong moisture-retention capacities of the polysaccharide from Sargassum horneri. Copyright © 2014 Elsevier B.V. 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.

Evaluation of free radicals scavenging and immunity-modulatory activities of Purslane polysaccharides.

PubMed

YouGuo, Chen; ZongJi, Shen; XiaoPing, Chen

2009-12-01

In this study, antioxidant and immunity-modulatory activities of Purslane polysaccharide were estimated. The results revealed that in a dose-dependent manner, Purslane polysaccharides could significantly scavenge superoxide anion, 1,1-diphenyl-2-picrylhydrazyl (DPPH(-)), nitric oxide and hydroxyl radicals. Furthermore, the Purslane polysaccharides could still effectively inhibit the red blood cell (RBC) haemolysis, and increase spleen, thymocyte T and B lymphocyte proliferation, it could be concluded that Purslane polysaccharides could be of considerable preventive and therapeutic significance to some free radical associated health problems such as ovarian cancer, by scavenging accumulating free radicals and enhancing immunity functions.

Envelope Structures of Gram-Positive Bacteria

PubMed Central

Rajagopal, Mithila; Walker, Suzanne

2016-01-01

Gram-positive organisms, including the pathogens Staphylococcus aureus, Streptococcus pneumoniae and Enterococcus faecalis, have dynamic cell envelopes that mediate interactions with the environment and serve as the first line of defense against toxic molecules. Major components of the cell envelope include peptidoglycan, which is a well-established target for antibiotics, teichoic acids, capsular polysaccharides, surface proteins, and phospholipids. These components can undergo modification to promote pathogenesis, decrease susceptibility to antibiotics and host immune defenses, and enhance survival in hostile environments. This chapter will cover the structure, biosynthesis and important functions of major cell envelope components in Gram-positive bacteria. Possible targets for new antimicrobials will be noted. PMID:26919863

Enzymes and other agents that enhance cell wall extensibility

NASA Technical Reports Server (NTRS)

Cosgrove, D. J.

1999-01-01

Polysaccharides and proteins are secreted to the inner surface of the growing cell wall, where they assemble into a network that is mechanically strong, yet remains extensible until the cells cease growth. This review focuses on the agents that directly or indirectly enhance the extensibility properties of growing walls. The properties of expansins, endoglucanases, and xyloglucan transglycosylases are reviewed and their postulated roles in modulating wall extensibility are evaluated. A summary model for wall extension is presented, in which expansin is a primary agent of wall extension, whereas endoglucanases, xyloglucan endotransglycosylase, and other enzymes that alter wall structure act secondarily to modulate expansin action.

Structure and dynamics of microbe-exuded polymers and their interactions with calcite surfaces.

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

Cygan, Randall Timothy; Mitchell, Ralph; Perry, Thomas D.

2005-12-01

Cation binding by polysaccharides is observed in many environments and is important for predictive environmental modeling, and numerous industrial and food technology applications. The complexities of these organo-cation interactions are well suited to predictive molecular modeling studies for investigating the roles of conformation and configuration of polysaccharides on cation binding. In this study, alginic acid was chosen as a model polymer and representative disaccharide and polysaccharide subunits were modeled. The ability of disaccharide subunits to bind calcium and to associate with the surface of calcite was investigated. The findings were extended to modeling polymer interactions with calcium ions.

Extraction of the same novel homoglycan mixture from two different strains of Bifidobacterium animalis and three strains of Bifidobacterium breve.

PubMed

Alhudhud, M; Sadiq, S; Ngo, H N; Hidalgo-Cantabrana, C; Ruas-Madiedo, P; van Sinderen, D; Humphreys, P N; Laws, A P

2018-06-15

Three strains of Bifidobacterium breve (JCM 7017, JCM 7019 and JCM 2258) and two strains of Bifidobacterium animalis subsp. lactis (AD011 and A1dOxR) were grown in broth cultures or on plates, and a standard exopolysaccharide extraction method was used in an attempt to recover exocellular polysaccharides. When the extracted materials were analysed by NMR it was clear that mixtures of polysaccharides were being isolated including exopolysaccharides (EPS) cell wall polysaccharides and intracellular polysaccharides. Treatment of the cell biomass from the B. breve strains, or the B. animalis subsp. lactis AD011 strain, with aqueous sodium hydroxide provided a very similar mixture of polysaccharides but without the EPS. The different polysaccharides were partially fractionated by selective precipitation from an aqueous solution upon the addition of increasing percentages of ethanol. The polysaccharides extracted from B. breve JCM 7017 grown in HBM media supplemented with glucose (or isotopically labelled D-glucose-1- 13 C) were characterised using 1D and 2D-NMR spectroscopy. Addition of one volume of ethanol generated a medium molecular weight glycogen (Mw=1×10 5 Da, yield 200 mg/l). The addition of two volumes of ethanol precipitated an intimate mixture of a low molecular weight β-(1→6)-glucan and a low molecular weight β-(1→6)-galactofuranan which could not be separated (combined yield 46 mg/l). When labelled D-glucose-1- 13 C was used as a carbon supplement, the label was incorporated into >95% of the anomeric carbons of each polysaccharide confirming they were being synthesised in situ. Similar 1 H NMR profiles were obtained for polysaccharides recovered from the cells of B. animalis subsp. lactis AD011and A1dOxR (in combination with an EPS), B. breve JCM 7017, B. breve JCM 7019, B. breve JCM 2258 and from an EPS (-ve) mutant of B. breve 7017 (a non-EPS producer).

Surface Proteins of Gram-Positive Bacteria and Mechanisms of Their Targeting to the Cell Wall Envelope

PubMed Central

Navarre, William Wiley; Schneewind, Olaf

1999-01-01

The cell wall envelope of gram-positive bacteria is a macromolecular, exoskeletal organelle that is assembled and turned over at designated sites. The cell wall also functions as a surface organelle that allows gram-positive pathogens to interact with their environment, in particular the tissues of the infected host. All of these functions require that surface proteins and enzymes be properly targeted to the cell wall envelope. Two basic mechanisms, cell wall sorting and targeting, have been identified. Cell well sorting is the covalent attachment of surface proteins to the peptidoglycan via a C-terminal sorting signal that contains a consensus LPXTG sequence. More than 100 proteins that possess cell wall-sorting signals, including the M proteins of Streptococcus pyogenes, protein A of Staphylococcus aureus, and several internalins of Listeria monocytogenes, have been identified. Cell wall targeting involves the noncovalent attachment of proteins to the cell surface via specialized binding domains. Several of these wall-binding domains appear to interact with secondary wall polymers that are associated with the peptidoglycan, for example teichoic acids and polysaccharides. Proteins that are targeted to the cell surface include muralytic enzymes such as autolysins, lysostaphin, and phage lytic enzymes. Other examples for targeted proteins are the surface S-layer proteins of bacilli and clostridia, as well as virulence factors required for the pathogenesis of L. monocytogenes (internalin B) and Streptococcus pneumoniae (PspA) infections. In this review we describe the mechanisms for both sorting and targeting of proteins to the envelope of gram-positive bacteria and review the functions of known surface proteins. PMID:10066836

Bacterial Molecular Signals in the Sinorhizobium fredii-Soybean Symbiosis

PubMed Central

López-Baena, Francisco J.; Ruiz-Sainz, José E.; Rodríguez-Carvajal, Miguel A.; Vinardell, José M.

2016-01-01

Sinorhizobium (Ensifer) fredii (S. fredii) is a rhizobial species exhibiting a remarkably broad nodulation host-range. Thus, S. fredii is able to effectively nodulate dozens of different legumes, including plants forming determinate nodules, such as the important crops soybean and cowpea, and plants forming indeterminate nodules, such as Glycyrrhiza uralensis and pigeon-pea. This capacity of adaptation to different symbioses makes the study of the molecular signals produced by S. fredii strains of increasing interest since it allows the analysis of their symbiotic role in different types of nodule. In this review, we analyze in depth different S. fredii molecules that act as signals in symbiosis, including nodulation factors, different surface polysaccharides (exopolysaccharides, lipopolysaccharides, cyclic glucans, and K-antigen capsular polysaccharides), and effectors delivered to the interior of the host cells through a symbiotic type 3 secretion system. PMID:27213334

Coevolution of yeast mannan digestion: Convergence of the civilized human diet, distal gut microbiome, and host immunity

PubMed Central

Abbott, D Wade; Martens, Eric C; Gilbert, Harry J; Cuskin, Fiona; Lowe, Elisabeth C

2015-01-01

The complex carbohydrates accessible to the distal gut microbiota (DGM) are key drivers in determining the structure of this ecosystem. Typically, plant cell wall polysaccharides and recalcitrant starch (i.e. dietary fiber), in addition to host glycans are considered the primary nutrients for the DGM; however, we recently demonstrated that α-mannans, highly branched polysaccharides that decorate the surface of yeast, are also nutrients for several members of Bacteroides spp. This relationship suggests that the advent of yeast in contemporary food technologies and the colonization of the intestine by endogenous fungi have roles in microbiome structure and function. Here we discuss the process of yeast mannan metabolism, and the intersection between various sources of intestinal fungi and their roles in recognition by the host innate immune system. PMID:26440374

The extracellular matrix of Volvox carteri: molecular structure of the cellular compartment.

PubMed

Ertl, H; Mengele, R; Wenzl, S; Engel, J; Sumper, M

1989-12-01

The extracellular matrix (ECM) of Volvox contains insoluble fibrous layers that surround individual cells at a distance to form contiguous cellular compartments. Using immunological techniques, we identified a sulfated surface glycoprotein (SSG 185) as the monomeric precursor of this substructure within the ECM. The primary structure of the SSG 185 poly-peptide chain has been derived from cDNA and genomic DNA. A central domain of the protein, 80 amino acid residues long, consists almost exclusively of hydroxyproline residues. The chemical structure of the highly sulfated polysaccharide covalently attached to SSG 185 has been determined by permethylation analysis. As revealed by EM, SSG 185 is a rod-shaped molecule with a 21-nm-long polysaccharide strand protruding from its central region. The chemical nature of the cross-links between SSG 185 monomers is discussed.

Sustained Nitric Oxide-Releasing Nanoparticles Induce Cell Death in Candida albicans Yeast and Hyphal Cells, Preventing Biofilm Formation In Vitro and in a Rodent Central Venous Catheter Model

PubMed Central

Ahmadi, Mohammed S.; Lee, Hiu Ham; Sanchez, David A.; Friedman, Adam J.; Tar, Moses T.; Davies, Kelvin P.; Nosanchuk, Joshua D.

2016-01-01

Candida albicans is a leading nosocomial pathogen. Today, candidal biofilms are a significant cause of catheter infections, and such infections are becoming increasingly responsible for the failure of medical-implanted devices. C. albicans forms biofilms in which fungal cells are encased in an autoproduced extracellular polysaccharide matrix. Consequently, the enclosed fungi are protected from antimicrobial agents and host cells, providing a unique niche conducive to robust microbial growth and a harbor for recurring infections. Here we demonstrate that a recently developed platform comprised of nanoparticles that release therapeutic levels of nitric oxide (NO-np) inhibits candidal biofilm formation, destroys the extracellular polysaccharide matrices of mature fungal biofilms, and hinders biofilm development on surface biomaterials such as the lumen of catheters. We found NO-np to decrease both the metabolic activity of biofilms and the cell viability of C. albicans in vitro and in vivo. Furthermore, flow cytometric analysis found NO-np to induce apoptosis in biofilm yeast cells in vitro. Moreover, NO-np behave synergistically when used in combination with established antifungal drug therapies. Here we propose NO-np as a novel treatment modality, especially in combination with standard antifungals, for the prevention and/or remediation of fungal biofilms on central venous catheters and other medical devices. PMID:26810653

Antioxidant activity of polysaccharide extracted from Ganoderma lucidum using response surface methodology.

PubMed

Kan, Yongjun; Chen, Tiqiang; Wu, Yanbin; Wu, Jianguo; Wu, Jinzhong

2015-01-01

Superfine grinding technology was applied for polysaccharide extraction from the fruiting bodies of Ganoderma lucidum, and response surface methodology (RSM) was used to optimize the effects of processing parameters on polysaccharide extraction yield. Results showed that the maximum yield of G. lucidum polysaccharides (GLP) was obtained at an optimum condition: extraction time 137 min, extraction temperature 66 ̊C, the ratio of water to material 35 mL/g, and the GLP extracting yield reached 2.44% under this condition. GLP were precipitated into three crude polysaccharides, viz. GLP40, GLP60 and GLP80. The basic characterization of polysaccharides was determined by using HPLC and FT-IR methods. GLP, GLP80, GLP60, and GLP40 were composed of Man, Rib, Glc, Gal and Fuc with the molar ratios of 1.27:0.36:22.89:1.61:0.33, 1.40:0.31:23.02:3.46:0.91, 0.96:0.34:25.76:2.47:0.46, and 2.81:1.42:23.83:1.61:0.33, respectively. The result of FT-IR suggested that the monosaccharide residue of the four polysaccharides was β-pyranoid ring. Moreover, the antioxidant activities of these four polysaccharides were evaluated. The results showed that GLP80 had the best reducing power, DPPH radical scavenging ability and oxygen radical scavenging ability followed by GLP, GLP60 and GLP40. Our results demonstrated that RSM might be a valuable technique for optimizing the efficient extraction of GLP, and G. lucidum could be considered as sources of natural antioxidants and preservatives of food industry. Moreover, polysaccharides, especially GLP80, extracted from the fruiting bodies of G. lucidum, exhibited promising antioxidant activities. Copyright © 2014 Elsevier B.V. All rights reserved.

Novel imaging technologies for characterization of microbial extracellular polysaccharides.

PubMed

Lilledahl, Magnus B; Stokke, Bjørn T

2015-01-01

Understanding of biology is underpinned by the ability to observe structures at various length scales. This is so in a historical context and is also valid today. Evolution of novel insight often emerges from technological advancement. Recent developments in imaging technologies that is relevant for characterization of extraceullar microbiological polysaccharides are summarized. Emphasis is on scanning probe and optical based techniques since these tools offers imaging capabilities under aqueous conditions more closely resembling the physiological state than other ultramicroscopy imaging techniques. Following the demonstration of the scanning probe microscopy principle, novel operation modes to increase data capture speed toward video rate, exploitation of several cantilever frequencies, and advancement of utilization of specimen mechanical properties as contrast, also including their mode of operation in liquid, have been developed on this platform. Combined with steps in advancing light microscopy with resolution beyond the far field diffraction limit, non-linear methods, and combinations of the various imaging modalities, the potential ultramicroscopy toolbox available for characterization of exopolysaccharides (EPS) are richer than ever. Examples of application of such ultramicroscopy strategies range from imaging of isolated microbial polysaccharides, structures being observed when they are involved in polyelectrolyte complexes, aspects of their enzymatic degradation, and cell surface localization of secreted polysaccharides. These, and other examples, illustrate that the advancement in imaging technologies relevant for EPS characterization supports characterization of structural aspects.

Localization of Cell Wall Polysaccharides in Normal and Compression Wood of Radiata Pine: Relationships with Lignification and Microfibril Orientation1

PubMed Central

Donaldson, Lloyd A.; Knox, J. Paul

2012-01-01

The distribution of noncellulosic polysaccharides in cell walls of tracheids and xylem parenchyma cells in normal and compression wood of Pinus radiata, was examined to determine the relationships with lignification and cellulose microfibril orientation. Using fluorescence microscopy combined with immunocytochemistry, monoclonal antibodies were used to detect xyloglucan (LM15), β(1,4)-galactan (LM5), heteroxylan (LM10 and LM11), and galactoglucomannan (LM21 and LM22). Lignin and crystalline cellulose were localized on the same sections used for immunocytochemistry by autofluorescence and polarized light microscopy, respectively. Changes in the distribution of noncellulosic polysaccharides between normal and compression wood were associated with changes in lignin distribution. Increased lignification of compression wood secondary walls was associated with novel deposition of β(1,4)-galactan and with reduced amounts of xylan and mannan in the outer S2 (S2L) region of tracheids. Xylan and mannan were detected in all lignified xylem cell types (tracheids, ray tracheids, and thick-walled ray parenchyma) but were not detected in unlignified cell types (thin-walled ray parenchyma and resin canal parenchyma). Mannan was absent from the highly lignified compound middle lamella, but xylan occurred throughout the cell walls of tracheids. Using colocalization measurements, we confirmed that polysaccharides containing galactose, mannose, and xylose have consistent correlations with lignification. Low or unsubstituted xylans were localized in cell wall layers characterized by transverse cellulose microfibril orientation in both normal and compression wood tracheids. Our results support the theory that the assembly of wood cell walls, including lignification and microfibril orientation, may be mediated by changes in the amount and distribution of noncellulosic polysaccharides. PMID:22147521

Absence of arabinan in the side chains of the pectic polysaccharides strongly associated with cell walls of Nicotiana plumbaginifolia non-organogenic callus with loosely attached constituent cells.

PubMed

Iwai, H; Ishii, T; Satoh, S

2001-10-01

When leaf disks from haploid plants of Nicotiana plumbaginifolia Viv. were transformed with T-DNA and cultured on shoot-inducing medium, nonorganogenic callus. designated nolac (for non-organogenic callus with loosely attached cells), appeared on approximately 7% of leaf disks. In contrast, normal callus was generated on T-DNA-transformed leaf disks from diploid plants and on non-transformed leaf disks from haploid and diploid plants. Transmission electron microscopy revealed that the middle lamellae and the cell walls of one line of mutant callus (nolac-H14) were barely stained by ruthenium red. even after demethylesterification with NaOH, whereas the entire cell wall and the middle lamella were strongly stained in normal callus. In cultures of nolac-H14 callus, the level of sugar components of pectic polysaccharides in the hemicellulose fraction was reduced and that in the culture medium was elevated, as compared with cultures of normal callus. These results indicate that pectic polysaccharides are not retained in the cell walls and middle lamellae of nolac-H14 callus. In nolac-H14, the ratio of arabinose to galactose was low in the pectic polysaccharides purified from all cell wall fractions and from the medium, in particular, in the hemicellulose fractions. The low levels of arabinofuranosyl (T-Araf, 5-Araf, 2,5-Araf, and 3,5-Araf) residues in the pectic polysaccharides of the hemicellulosic fraction of nolac-H,14 indicated that no neutral-sugar side chains, composed mainly of linear arabinan. were present in nolac-H14. Arabinose-rich pectins. which are strongly associated with cellulose-hemicellulose complexes, might play an important role in intercellular attachment in the architecture of the cell wall.

Two methods for one-point anchoring of a linear polysaccharide on a gold surface.

PubMed

Hoypierres, Julia; Dulong, Virginie; Rihouey, Christophe; Alexandre, Stéphane; Picton, Luc; Thébault, Pascal

2015-01-01

Two strategies to achieve a one-point anchoring of a hydrolyzed pullulan (P9000) on a gold surface are compared. The first strategy consists of forming a self-assembled monolayer of a 6-amino-1-hexanethiol (AHT) and then achieving reductive amination on the surface between the aminated surface and the aldehyde of the polysaccharide reductive end sugar. The second consists of incorporating a thiol function at the extremity of the pullulan (via the same reductive amination), leading to P9000-AHT and then immobilizing it on gold by a spontaneous reaction between solid gold and thiol. The modified pullulan was characterized by NMR and size-exclusion chromatography coupled to a light-scattering detector. P9000-AHT appears to be in a disulfide dimer form in solution but recovers its unimer form with dithiothreitol (DTT) treatment. The comparison of the two strategies by contact angle and XPS revealed that the second strategy is more efficient for the pullulan one-point anchoring. P9000-AHT even in its dimer form is easily grafted onto the surface. The grafted polymer seems to be more in a coil conformation than in a rigid brush. Furthermore, QCM measurements highlighted that the second strategy leads to a grafting density of around 3.5 × 10(13) molecules·cm(-2) corresponding to a high surface coverage. The elaboration of a dense and oriented layer of polysaccharides covalently linked to a gold surface might enhance the use of such modified polysaccharides in various fields.

Changes in levels of cell wall constituents in wheat seedlings grown under continuous hypergravity conditions

NASA Astrophysics Data System (ADS)

Wakabayashi, K.; Soga, K.; Kamisaka, S.; Hoson, T.

Effects of continuous hypergravity stimuli on the amounts and composition of cell wall constituents were investigated in wheat shoots. Hypergravity (300 g) treatment for three days after germination increased the net amount of cell wall polysaccharides such as hemicellulose and cellulose, but reduced the shoot elongation. As a result, the amount of cell wall polysaccharides per unit length of shoot increased under hypergravity. The hemicellulose fraction contained polysaccharides in the middle and low molecular mass range (5 kDa-1 MDa) and increased in response to hypergravity. Also, the amounts of arabinose (Ara) and xylose (Xyl), the major sugar components of the hemicellulose fraction, increased under hypergravity conditions. In addition to wall polysaccharides, hypergravity increased the amounts of cell wall-bound phenolic acids, such as ferulic acid (FA) and diferulic acid (DFA). Furthermore, the activity of phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) was enhanced under hypergravity conditions. These results suggest that continuous hypergravity stimulates the synthesis of cell wall constituents, especially hemicellulosic arabinoxylans and cell wall-bound FA and DFA in wheat shoots. The increased PAL activity may promote the formation of FA and DFA. These changes in cell wall architecture may be involved in making rigid and tough cell walls under hypergravity conditions and thereby contribute to the ability of plant to sustain their structures against gravitational stimuli.

Molecular Assembly of Polysaccharide-Based Microcapsules and Their Biomedical Applications.

PubMed

Feng, Xiyun; Du, Cuiling; Li, Junbai

2016-08-01

Advanced multifunctional microcapsules have revealed great potential in biomedical applications owing to their tunable size, shape, surface properties, and stimuli responsiveness. Polysaccharides are one of the most acceptable biomaterials for biomedical applications because of their outstanding virtues such as biocompatibility, biodegradability, and low toxicity. Many efforts have been devoted to investigating novel molecular design and efficient building blocks for polysaccharide-based microcapsules. In this Personal Account, we first summarize the common features of polysaccharides and the main principles of the design and fabrication of polysaccharide-based microcapsules, and further discuss their applications in biomedical areas and perspectives for future research. © 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

A rhamnose-rich O-antigen mediates adhesion, virulence, and host colonization for the xylem-limited phytopathogen Xylella fastidiosa.

PubMed

Clifford, Jennifer C; Rapicavoli, Jeannette N; Roper, M Caroline

2013-06-01

Xylella fastidiosa is a gram-negative, xylem-limited bacterium that causes a lethal disease of grapevine called Pierce's disease. Lipopolysaccharide (LPS) composes approximately 75% of the outer membrane of gram-negative bacteria and, because it is largely displayed on the cell surface, it mediates interactions between the bacterial cell and its surrounding environment. LPS is composed of a conserved lipid A-core oligosaccharide component and a variable O-antigen portion. By targeting a key O-antigen biosynthetic gene, we demonstrate the contribution of the rhamnose-rich O-antigen to surface attachment, cell-cell aggregation, and biofilm maturation: critical steps for successful infection of the host xylem tissue. Moreover, we have demonstrated that a fully formed O-antigen moiety is an important virulence factor for Pierce's disease development in grape and that depletion of the O-antigen compromises its ability to colonize the host. It has long been speculated that cell-surface polysaccharides play a role in X. fastidiosa virulence and this study confirms that LPS is a major virulence factor for this important agricultural pathogen.

Determination of glycoside hydrolase specificities during hydrolysis of plant cell walls using glycome profiling

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

Walker, Johnnie A.; Pattathil, Sivakumar; Bergeman, Lai F.

Glycoside hydrolases (GHs) are enzymes that hydrolyze polysaccharides into simple sugars. To better understand the specificity of enzyme hydrolysis within the complex matrix of polysaccharides found in the plant cell wall, we studied the reactions of individual enzymes using glycome profiling, where a comprehensive collection of cell wall glycan-directed monoclonal antibodies are used to detect polysaccharide epitopes remaining in the walls after enzyme treatment and quantitative nanostructure initiator mass spectrometry (oxime-NIMS) to determine soluble sugar products of their reactions. Single, purified enzymes from the GH5_4, GH10, and GH11 families of glycoside hydrolases hydrolyzed hemicelluloses as evidenced by the loss ofmore » specific epitopes from the glycome profiles in enzyme-treated plant biomass. The glycome profiling data were further substantiated by oxime-NIMS, which identified hexose products from hydrolysis of cellulose, and pentose-only and mixed hexose-pentose products from the hydrolysis of hemicelluloses. The GH10 enzyme proved to be reactive with the broadest diversity of xylose-backbone polysaccharide epitopes, but was incapable of reacting with glucose-backbone polysaccharides. In contrast, the GH5 and GH11 enzymes studied here showed the ability to react with both glucose- and xylose-backbone polysaccharides. The identification of enzyme specificity for a wide diversity of polysaccharide structures provided by glycome profiling, and the correlated identification of soluble oligosaccharide hydrolysis products provided by oxime-NIMS, offers a unique combination to understand the hydrolytic capabilities and constraints of individual enzymes as they interact with plant biomass.« less

Determination of glycoside hydrolase specificities during hydrolysis of plant cell walls using glycome profiling

DOE PAGES

Walker, Johnnie A.; Pattathil, Sivakumar; Bergeman, Lai F.; ...

2017-02-02

Glycoside hydrolases (GHs) are enzymes that hydrolyze polysaccharides into simple sugars. To better understand the specificity of enzyme hydrolysis within the complex matrix of polysaccharides found in the plant cell wall, we studied the reactions of individual enzymes using glycome profiling, where a comprehensive collection of cell wall glycan-directed monoclonal antibodies are used to detect polysaccharide epitopes remaining in the walls after enzyme treatment and quantitative nanostructure initiator mass spectrometry (oxime-NIMS) to determine soluble sugar products of their reactions. Single, purified enzymes from the GH5_4, GH10, and GH11 families of glycoside hydrolases hydrolyzed hemicelluloses as evidenced by the loss ofmore » specific epitopes from the glycome profiles in enzyme-treated plant biomass. The glycome profiling data were further substantiated by oxime-NIMS, which identified hexose products from hydrolysis of cellulose, and pentose-only and mixed hexose-pentose products from the hydrolysis of hemicelluloses. The GH10 enzyme proved to be reactive with the broadest diversity of xylose-backbone polysaccharide epitopes, but was incapable of reacting with glucose-backbone polysaccharides. In contrast, the GH5 and GH11 enzymes studied here showed the ability to react with both glucose- and xylose-backbone polysaccharides. The identification of enzyme specificity for a wide diversity of polysaccharide structures provided by glycome profiling, and the correlated identification of soluble oligosaccharide hydrolysis products provided by oxime-NIMS, offers a unique combination to understand the hydrolytic capabilities and constraints of individual enzymes as they interact with plant biomass.« less

A polysaccharide from Dictyophora indusiata inhibits the immunosuppressive function of cancer-associated fibroblasts.

PubMed

Han, Shuyu; Ma, Chaoxiong; Hu, Minghua; Wang, Yuanyuan; Ma, Fangli; Tao, Ning; Qin, Zhihai

2017-10-01

Reversing the function of cancer-associated fibroblasts (CAFs) may improve the efficacy of cancer therapy. Here, we isolated a novel polysaccharide from Dictyophora indusiata (ZSP4) and examined its effects on the function of prostate CAFs. The supernatant of prostate CAFs can stimulate the proliferation of immune cells and inhibit the growth of CD4+/CD8+ T cells. However, after ZSP4 stimulation, the functions of prostate CAFs were inhibited. The mechanism experiment shows that ZSP4 can stimulate prostate CAFs by down-regulating the expression of α-smooth muscle actin. Polysaccharides extracted from Dictyophora indusiata stimulate the proliferation of immune cells and reverse the immune-suppressive functions of prostate CAFs, shedding new light on the development of novel anticancer strategies. The endocrine therapy used to treat prostate cancer aims to eliminate androgenic activity from prostatic tissue; these therapies are painful and of poor therapeutic effect. In this study, we found that polysaccharides extracted from Dictyophora indusiata may affect the micro-environment of tumours and inhibit the growth of the tumours. Our results suggest that polysaccharides may modulate negative immune regulation and enhance antitumour immunity, which is important for clinical therapy. Copyright © 2017 John Wiley & Sons, Ltd.

Structural diversity of alkali-soluble polysaccharides from the fruit cell walls of tucumã (Astrocaryum aculeatum), a commelinid monocotyledon from the family Arecaceae.

PubMed

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

2017-09-01

The polysaccharide compositions of primary and secondary cell walls of members of the family Arecaceae in the commelinid clade of monocotyledonous plants have previously been found to be distinguishable from other commelinid families, and to be more similar to those of non-commelinids. However, few studies have been conducted. We aimed to extract and characterize the main cell-wall polysaccharides in the fruit pulp of tucumã (Astrocaryum aculeatum), a member of Arecaceae family. Hemicellulosic polysaccharides extracted by alkali from the fruit pulp were present in greater proportions (6.4% yield) than water-extracted ones (3.0% yield). Thus, the former was analyzed using monosaccharide composition, methylation, molecular weight determination and 13 C-NMR data. The tucumã alkaline extract presented a highly ramified acidic galactoarabinoxylan (53.7%), a linear (1 → 5)-linked α-L-arabinan (27.8%), a low branched glucuronoxylan (14.1%) and small portions of a xyloglucan (4.4%). The major polysaccharide found in A. aculeatum (acidic galactoarabinoxylan) is similar to those found in other commelinid plants such as grasses and cereals. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

The pre-ulcerative phase of carrageenan-induced colonic ulceration in the guinea-pig.

PubMed Central

Marcus, S. N.; Marcus, A. J.; Marcus, R.; Ewen, S. W.; Watt, J.

1992-01-01

The pre-ulcerative phase of carrageenan-induced colonic ulceration was investigated in guinea-pigs supplied 3% degraded carrageenan as an aqueous solution as drinking fluid for 2 or 3 days during which no ulceration of the bowel was observed with the naked eye or dissecting microscope. Mucosal microscopic changes, from caecum to rectum, were multifocal and included cellular infiltrates, dilatation of glands, crypt abscesses, micro-ulcers and sulphated polysaccharide in the lamina propria. Sulphated polysaccharide was also demonstrated histologically for the first time within the surface epithelium and showed ultrastructural features similar to carrageenan. The results indicate that colonic epithelium in the guinea-pig is capable of macromolecular absorption. Carrageenan, a highly active polyanionic electrolyte, within the surface epithelial cells is most likely a primary factor in the breakdown of mucosal integrity. Macromolecular absorption causing enteropathy of the large bowel is a new pathophysiological concept which may have implications in man, particularly in the pathology of large bowel disease. Images Fig. 7 Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:1356411

Comparison of cell wall polysaccharide hydrolysis by a dilute acid/enzymatic saccharification process and rumen microorganisms

USDA-ARS?s Scientific Manuscript database

Evaluation of biomass crops for breeding or pricing purposes requires an assay that predicts performance of biomass in the bioenergy conversion process. Cell wall polysaccharide hydrolysis by dilute sulfuric acid pretreatment at 121 degrees C followed by cellulase hydrolysis for 72 h (CONV) and in v...

Effects of calcium treatment and low temperature storage on cell wall polysaccharide nanostructures and quality of postharvest apricot (Prunus armeniaca).

PubMed

Liu, Hui; Chen, Fusheng; Lai, Shaojuan; Tao, Junrui; Yang, Hongshun; Jiao, Zhonggao

2017-06-15

Cell wall polysaccharides play an important role in postharvest fruit texture softening. Effects of calcium treatment combined with cold storage on the physical properties, polysaccharide content and nanostructure of apricots were investigated. Apricots were immersed in distilled water, 1% or 3% w/v calcium chloride, then stored at 5°C or 10°C. Storage at 5°C significantly improved apricot quality and shelf life. Significant changes in the concentration and nanostructure of cell wall pectins and hemicelluloses revealed their disassembly and degradation during apricot storage. These modifications could be retarded by 1% w/v calcium chloride treatment. Meanwhile, the basic width units of apricot cell wall polysaccharide chains were 11.7, 31.2 and 39.1nm for water-soluble pectin, 11.7, 17.6 and 19.5nm for chelate-soluble pectin, and 15.6 and 23.4nm for hemicellulose. The results suggest that texture of apricots can be effectively maintained by 1% calcium chloride treatment and storage at 5°C. Copyright © 2017 Elsevier Ltd. All rights reserved.

Arabidopsis and Brachypodium distachyon Transgenic Plants Expressing Aspergillus nidulans Acetylesterases Have Decreased Degree of Polysaccharide Acetylation and Increased Resistance to Pathogens1[C][W][OA

PubMed Central

Pogorelko, Gennady; Lionetti, Vincenzo; Fursova, Oksana; Sundaram, Raman M.; Qi, Mingsheng; Whitham, Steven A.; Bogdanove, Adam J.; Bellincampi, Daniela; Zabotina, Olga A.

2013-01-01

The plant cell wall has many significant structural and physiological roles, but the contributions of the various components to these roles remain unclear. Modification of cell wall properties can affect key agronomic traits such as disease resistance and plant growth. The plant cell wall is composed of diverse polysaccharides often decorated with methyl, acetyl, and feruloyl groups linked to the sugar subunits. In this study, we examined the effect of perturbing cell wall acetylation by making transgenic Arabidopsis (Arabidopsis thaliana) and Brachypodium (Brachypodium distachyon) plants expressing hemicellulose- and pectin-specific fungal acetylesterases. All transgenic plants carried highly expressed active Aspergillus nidulans acetylesterases localized to the apoplast and had significant reduction of cell wall acetylation compared with wild-type plants. Partial deacetylation of polysaccharides caused compensatory up-regulation of three known acetyltransferases and increased polysaccharide accessibility to glycosyl hydrolases. Transgenic plants showed increased resistance to the fungal pathogens Botrytis cinerea and Bipolaris sorokiniana but not to the bacterial pathogens Pseudomonas syringae and Xanthomonas oryzae. These results demonstrate a role, in both monocot and dicot plants, of hemicellulose and pectin acetylation in plant defense against fungal pathogens. PMID:23463782

Resonant Soft X-ray Scattering of Cellulose Microstructure in Plant Primary Cell Walls

NASA Astrophysics Data System (ADS)

Ye, Dan; Kiemle, Sarah N.; Wang, Cheng; Cosgrove, Daniel J.; Gomez, Esther W.; Gomez, Enrique D.

Cellulosic biomass is the most abundant raw material available for the production of renewable and sustainable biofuels. Breaking down cellulose is the rate-limiting step in economical biofuel production; therefore, a detailed understanding of the microscopic structure of plant cell walls is required to develop efficient biofuel conversion methods. Primary cell walls are key determinants of plant growth and mechanics. Their structure is complex and heterogeneous, making it difficult to elucidate how various components such as pectin, hemicellulose, and cellulose contribute to the overall structure. The electron density of these wall components is similar; such that conventional hard X-ray scattering does not generate enough contrast to resolve the different elements of the polysaccharide network. The chemical specificity of resonant soft X-ray scattering allows contrast to be generated based on differences in chemistry of the different polysaccharides. By varying incident X-ray energies, we have achieved increased scattering contrast between cellulose and other polysaccharides from primary cell walls of onions. By performing scattering at certain energies, features of the network structure of the cell wall are resolved. From the soft X-ray scattering results, we obtained the packing distance of cellulose microfibrils embedded in the polysaccharide network.

Fucans, but Not Fucomannoglucuronans, Determine the Biological Activities of Sulfated Polysaccharides from Laminaria saccharina Brown Seaweed

PubMed Central

Ushakova, Natalia A.; Preobrazhenskaya, Marina E.; Piccoli, Antonio; Totani, Licia; Ustyuzhanina, Nadezhda E.; Bilan, Maria I.; Usov, Anatolii I.; Grachev, Alexey A.; Morozevich, Galina E.; Berman, Albert E.; Sanderson, Craig J.; Kelly, Maeve; Di Gregorio, Patrizia; Rossi, Cosmo; Tinari, Nicola; Iacobelli, Stefano; Rabinovich, Gabriel A.; Nifantiev, Nikolay E.

2011-01-01

Sulfated polysaccharides from Laminaria saccharina (new name: Saccharina latissima) brown seaweed show promising activity for the treatment of inflammation, thrombosis, and cancer; yet the molecular mechanisms underlying these properties remain poorly understood. The aim of this work was to characterize, using in vitro and in vivo strategies, the anti-inflammatory, anti-coagulant, anti-angiogenic, and anti-tumor activities of two main sulfated polysaccharide fractions obtained from L. saccharina: a) L.s.-1.0 fraction mainly consisting of O-sulfated mannoglucuronofucans and b) L.s.-1.25 fraction mainly composed of sulfated fucans. Both fractions inhibited leukocyte recruitment in a model of inflammation in rats, although L.s.-1.25 appeared to be more active than L.s.-1.0. Also, these fractions inhibited neutrophil adhesion to platelets under flow. Only fraction L.s.-1.25, but not L.s.-1.0, displayed anticoagulant activity as measured by the activated partial thromboplastin time. Investigation of these fractions in angiogenesis settings revealed that only L.s.-1.25 strongly inhibited fetal bovine serum (FBS) induced in vitro tubulogenesis. This effect correlated with a reduction in plasminogen activator inhibitor-1 (PAI-1) levels in L.s.-1.25-treated endothelial cells. Furthermore, only parent sulfated polysaccharides from L. saccharina (L.s.-P) and its fraction L.s.-1.25 were powerful inhibitors of basic fibroblast growth factor (bFGF) induced pathways. Consistently, the L.s.-1.25 fraction as well as L.s.-P successfully interfered with fibroblast binding to human bFGF. The incorporation of L.s.-P or L.s.-1.25, but not L.s.-1.0 into Matrigel plugs containing melanoma cells induced a significant reduction in hemoglobin content as well in the frequency of tumor-associated blood vessels. Moreover, i.p. administrations of L.s.-1.25, as well as L.s.-P, but not L.s.-1.0, resulted in a significant reduction of tumor growth when inoculated into syngeneic mice. Finally, L.s.-1.25 markedly inhibited breast cancer cell adhesion to human platelet-coated surfaces. Thus, sulfated fucans are mainly responsible for the anti-inflammatory, anticoagulant, antiangiogenic, and antitumor activities of sulfated polysaccharides from L. saccharina brown seaweed. PMID:21387013

Anticoagulant, antiherpetic and antibacterial activities of sulphated polysaccharide from Indian medicinal plant Tridax procumbens L. (Asteraceae).

PubMed

Naqash, Shabeena Yousuf; Nazeer, R A

2011-10-01

The sulphated polysaccharide from the widespread Tridax procumbens plant was studied for the anticoagulant, antiherpetic and antibacterial activity. The anticoagulant activity was determined by the activated partial thromboplastin time assay. The sulphated polysaccharide from T. procumbens represented potent anticoagulant reaching the efficacy to heparin and chondroitin sulphate. Moreover, the sulphated polysaccharide extracted from T. procumbens was found non-toxic on Vero cell lines up to the concentration of 200 μg/ml. Sulphated polysaccharide exhibited detectable antiviral effect towards HSV-1 with IC(50) value 100-150 μg/ml. Furthermore, sulphated polysaccharide from T. procumbens was highly inhibitory against the bacterial strains Vibrio alginolyticus and Vibrio harveyi isolated from oil sardine.

FT-IR and FT-Raman characterization of non-cellulosic polysaccharides fractions isolated from plant cell wall.

PubMed

Chylińska, Monika; Szymańska-Chargot, Monika; Zdunek, Artur

2016-12-10

The purpose of this work was to reveal the structural changes of cell wall polysaccharides' fractions during tomato fruit development by analysis of spectral data. Mature green and red ripe tomato fruit were taken into consideration. The FT-IR spectra of water soluble pectin (WSP), imidazole soluble pectin (ISP) and diluted alkali soluble pectin (DASP) contained bands typical for pectins. Whereas for KOH fraction spectra bands typical for hemicelluloses were present. The FT-IR spectra showed the drop down of esterification degree of WSP and ISP polysaccharides during maturation. The changes in polysaccharides structure revealed by spectra were the most visible in the case of pectic polysaccharides. The WSP and DASP fraction pectins molecules length were shortened during tomato maturation and ripening. Whereas the ISP fraction spectra analysis showed that this fraction contained rhamnogalacturonan I, but also for red ripe was rich in pectic galactan comparing with ISP fraction from mature green. Copyright © 2016 Elsevier Ltd. All rights reserved.

High molecular weight of polysaccharides from Hericium erinaceus against amyloid beta-induced neurotoxicity.

PubMed

Cheng, Jai-Hong; Tsai, Chia-Ling; Lien, Yi-Yang; Lee, Meng-Shiou; Sheu, Shyang-Chwen

2016-06-07

Hericium erinaceus (HE) is a well-known mushroom in traditional Chinese food and medicine. HE extracts from the fruiting body and mycelia not only exhibit immunomodulatory, antimutagenic and antitumor activity but also have neuroprotective properties. Here, we purified HE polysaccharides (HEPS), composed of two high molecular weight polysaccharides (1.7 × 10(5) Da and 1.1 × 10(5) Da), and evaluated their protective effects on amyloid beta (Aβ)-induced neurotoxicity in rat pheochromocytoma PC12 cells. HEPS were prepared and purified using a 95 % ethanol extraction method. The components of HEPS were analyzed and the molecular weights of the polysaccharides were determined using high-pressure liquid chromatography (HPLC). The neuroprotective effects of the polysaccharides were evaluated through a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and an MTT assay and by quantifying reactive oxygen species (ROS) and mitochondrial membrane potentials (MMP) of Aβ-induced neurotoxicity in cells. Our results showed that 250 μg/ml HEPS was harmless and promoted cell viability with 1.2 μM Aβ treatment. We observed that the free radical scavenging rate exceeded 90 % when the concentration of HEPS was higher than 1 mg/mL in cells. The HEPS decreased the production of ROS from 80 to 58 % in a dose-dependent manner. Cell pretreatment with 250 μg/mL HEPS significantly reduced Aβ-induced high MMPs from 74 to 51 % and 94 to 62 % at 24 and 48 h, respectively. Finally, 250 μg/mL of HEPS prevented Aβ-induced cell shrinkage and nuclear degradation of PC12 cells. Our results demonstrate that HEPS exhibit antioxidant and neuroprotective effects on Aβ-induced neurotoxicity in neurons.

Polysaccharide nano-vesicular multidrug carriers for synergistic killing of cancer cells.

PubMed

Pramod, P S; Shah, Ruchira; Chaphekar, Sonali; Balasubramanian, Nagaraj; Jayakannan, Manickam

2014-10-21

Multi-drug delivery based on polymer nano-scaffolds is an essential protocol to be developed for better administration of anticancer drugs to enhance their therapeutic efficacies against cancer cells. Here, we report dual delivery polysaccharide nano-vesicles that are capable of loading and delivering both water soluble and water insoluble drugs together in a single polymer scaffold. The selective rupture of the nano-vesicular assembly under intracellular enzyme conditions allowed the simultaneous delivery of a hydrophobic drug camptothecin (CPT) and hydrophilic drug doxorubicin (DOX) supporting their synergistic killing of breast and colon cancer cells. The polysaccharide nano-vesicles have allowed us to address a few important questions regarding the need for multiple drug administration in cancer cells including (a) the role of simultaneous drug release, (b) antagonistic versus synergistic effects of drug combinations and (c) how these are affected by the ratio of drugs. Further, evaluation of the role of caveolae in endocytosis of these polymer scaffolds was also made. The vesicular scaffolds were found to preserve and deliver DOX resulting in 50-60% better killing of cancer cells than the free drug. Additionally, dual loaded nano-vesicles when compared to drug cocktails with individual drugs in separate nano-vesicles (at comparable molar ratios) suggest the relative drug concentration following release and mode of delivery to be both important in cancer cell killing. Results from these experiments have revealed newly developed polysaccharide nano-vesicles loaded with DOX and CPT drugs as potential candidates for improved breast cancer cell killing. Thus, these custom-designed polysaccharide nano-vesicles provide a new perspective on multi-anticancer drug delivery systems and their efficacy.

Automated glycan assembly of galactosylated xyloglucan oligosaccharides and their recognition by plant cell wall glycan-directed antibodies.

PubMed

Dallabernardina, Pietro; Ruprecht, Colin; Smith, Peter J; Hahn, Michael G; Urbanowicz, Breeanna R; Pfrengle, Fabian

2017-12-06

We report the automated glycan assembly of oligosaccharides related to the plant cell wall hemicellulosic polysaccharide xyloglucan. The synthesis of galactosylated xyloglucan oligosaccharides was enabled by introducing p-methoxybenzyl (PMB) as a temporary protecting group for automated glycan assembly. The generated oligosaccharides were printed as microarrays, and the binding of a collection of xyloglucan-directed monoclonal antibodies (mAbs) to the oligosaccharides was assessed. We also demonstrated that the printed glycans can be further enzymatically modified while appended to the microarray surface by Arabidopsis thaliana xyloglucan xylosyltransferase 2 (AtXXT2).

Structure and in vitro anticancer activity of sulfated O-polysaccharide from marine bacterium Poseidonocella pacifica KMM 9010T.

PubMed

Kokoulin, Maxim S; Kuzmich, Alexandra S; Kalinovsky, Anatoly I; Rubtsov, Eugene S; Romanenko, Lyudmila A; Mikhailov, Valery V; Komandrova, Nadezhda A

2017-12-15

We presented the structure of the sulfated polysaccharide moiety and anticancer activity in vitro of the О-deacylated lipopolysaccharide (DPS) isolated from the marine bacterium Poseidonocella pacifica KMM 9010 T . The structure of O-polysaccharide was investigated by chemical methods along with 1 H and 13 C NMR spectroscopy. The O-polysaccharide was built up of sulfated disaccharide repeating units consisted of d-rhamnose (d-Rhaр) and 3-deoxy-d-manno-oct-2-ulosonic acid (Kdop): →7)-β-Kdoр4Ac5S-(2→3)-β-d-Rhaр2S-(1→. We demonstrated that the DPS from P. pacifica KMM 9010 T non-toxic for normal mouse epidermal cells (JB6 Cl41 cell line) and inhibited colony formation of human colorectal carcinoma HT-29, breast adenocarcinoma MCF-7 and melanoma SK-MEL-5 cells in a dose-dependent manner. Copyright © 2017 Elsevier Ltd. All rights reserved.

A New Route of Fucoidan Immobilization on Low Density Polyethylene and Its Blood Compatibility and Anticoagulation Activity

PubMed Central

Ozaltin, Kadir; Lehocký, Marián; Humpolíček, Petr; Pelková, Jana; Sáha, Petr

2016-01-01

Beside biomaterials’ bulk properties, their surface properties are equally important to control interfacial biocompatibility. However, due to the inadequate interaction with tissue, they may cause foreign body reaction. Moreover, surface induced thrombosis can occur when biomaterials are used for blood containing applications. Surface modification of the biomaterials can bring enhanced surface properties in biomedical applications. Sulfated polysaccharide coatings can be used to avoid surface induced thrombosis which may cause vascular occlusion (blocking the blood flow by blood clot), which results in serious health problems. Naturally occurring heparin is one of the sulfated polysaccharides most commonly used as an anticoagulant, but its long term usage causes hemorrhage. Marine sourced sulfated polysaccharide fucoidan is an alternative anticoagulant without the hemorrhage drawback. Heparin and fucoidan immobilization onto a low density polyethylene surface after functionalization by plasma has been studied. Surface energy was demonstrated by water contact angle test and chemical characterizations were carried out by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Surface morphology was monitored by scanning electron microscope and atomic force microscope. Finally, their anticoagulation activity was examined for prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin time (TT). PMID:27294915

Modification of cell wall polysaccharides during retting of cassava roots.

PubMed

Ngolong Ngea, Guillaume Legrand; Guillon, Fabienne; Essia Ngang, Jean Justin; Bonnin, Estelle; Bouchet, Brigitte; Saulnier, Luc

2016-12-15

Retting is an important step in traditional cassava processing that involves tissue softening of the roots to transform the cassava into flour and various food products. The tissue softening that occurs during retting was attributed to the degradation of cell wall pectins through the action of pectin-methylesterase and pectate-lyase that possibly originated from a microbial source or the cassava plant itself. Changes in cell wall composition were investigated during retting using chemical analysis, specific glycanase degradation and immuno-labelling of cell wall polysaccharides. Pectic 1,4-β-d-galactan was the main cell wall polysaccharide affected during the retting of cassava roots. This result suggested that better control of pectic galactan degradation and a better understanding of the degradation mechanism by endogenous endo-galactanase and/or exogenous microbial enzymes might contribute to improve the texture properties of cassava products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Inhibition of lipopolysaccharide (LPS)-induced neuroinflammatory response by polysaccharide fractions of Khaya grandifoliola (C.D.C.) stem bark, Cryptolepis sanguinolenta (Lindl.) Schltr and Cymbopogon citratus Stapf leaves in raw 264.7 macrophages and U87 glioblastoma cells.

PubMed

Mediesse, Francine Kengne; Boudjeko, Thaddée; Hasitha, Anantharaju; Gangadhar, Matharasala; Mbacham, Wilfred Fon; Yogeeswari, Perumal

2018-03-12

Khaya grandifoliola (C.D.C.) stem bark, Cymbopogon citratus (Stapf) and Cryptolepis sanguinolenta (Lindl.) Schltr leaves are used in Cameroonian traditional medicine for the treatment of inflammatory diseases. Several studies have been performed on the biological activities of secondary metabolites extracted from these plants. However, to the best of our knowledge, the anti-neuro inflammatory and protective roles of the polysaccharides of these three plants have not yet been elucidated. This study aimed at investigating potential use of K. grandifoliola, C. sanguinolenta and C. citratus polysaccharides in the prevention of chronic inflammation. Firstly, the composition of polysaccharide fractions isolated from K. grandifoliola stem bark (KGF), C. sanguinolenta (CSF) and C. citratus (CCF) leaves was assessed. Secondly, the cytotoxicity was evaluated on Raw 264.7 macrophages and U87-MG glioblastoma cell lines by the MTT assay. This was followed by the in vitro evaluation of the ability of KGF, CSF and CCF to inhibit lipopolysaccharides (LPS) induced overproduction of various pro-inflammatory mediators (NO, ROS and IL1β, TNFα, IL6, NF-kB cytokines). This was done in Raw 264.7 and U87-MG cells. Finally, the in vitro protective effect of KGF, CSF and CCF against LPS-induced toxicity in the U87-MG cells was evaluated. CCF was shown to mostly contain sugar and no polyphenol while KGP and CSP contained very few amounts of these metabolites (≤ 2%). The three polysaccharide fractions were non-toxic up to 100 μg.mL - 1 . All the polysaccharides at 10 μg/mL inhibited NO production, but only KGF and CCF at 12.5 μg/mL down-regulated LPS-induced ROS overproduction. Finally, 100 μg/mL LPS reduced 50% of U87 cell viability, and pre-treatment with the three polysaccharides significantly increased the proliferation. These results suggest that the polysaccharides of K. grandifoliola, C. citratus and C. sanguinolenta could be beneficial in preventing/treating neurodegenerative diseases in which neuroinflammation is part of the pathophysiology.

Chemical Synthesis of Oligosaccharides Related to the Cell Walls of Plants and Algae.

PubMed

Kinnaert, Christine; Daugaard, Mathilde; Nami, Faranak; Clausen, Mads H

2017-09-13

Plant cell walls are composed of an intricate network of polysaccharides and proteins that varies during the developmental stages of the cell. This makes it very challenging to address the functions of individual wall components in cells, especially for highly complex glycans. Fortunately, structurally defined oligosaccharides can be used as models for the glycans, to study processes such as cell wall biosynthesis, polysaccharide deposition, protein-carbohydrate interactions, and cell-cell adhesion. Synthetic chemists have focused on preparing such model compounds, as they can be produced in good quantities and with high purity. This Review contains an overview of those plant and algal polysaccharides that have been elucidated to date. The majority of the content is devoted to detailed summaries of the chemical syntheses of oligosaccharide fragments of cellulose, hemicellulose, pectin, and arabinogalactans, as well as glycans unique to algae. Representative synthetic routes within each class are discussed in detail, and the progress in carbohydrate chemistry over recent decades is highlighted.

Isolation of the Cell Wall.

PubMed

Canut, Hervé; Albenne, Cécile; Jamet, Elisabeth

2017-01-01

This chapter describes a method allowing the purification of the cell wall for studying both polysaccharides and proteins. The plant primary cell wall is mainly composed of polysaccharides (90-95 % in mass) and of proteins (5-10 %). At the end of growth, specialized cells may synthesize a lignified secondary wall composed of polysaccharides (about 65 %) and lignin (about 35 %). Due to its composition, the cell wall is the cellular compartment having the highest density and this property is used for its purification. It plays critical roles during plant development and in response to environmental constraints. It is largely used in the food and textile industries as well as for the production of bioenergy. All these characteristics and uses explain why its study as a true cell compartment is of high interest. The proposed method of purification can be used for large amount of material but can also be downscaled to 500 mg of fresh material. Tools for checking the quality of the cell wall preparation, such as protein analysis and microscopy observation, are also provided.

Sustained Nitric Oxide-Releasing Nanoparticles Induce Cell Death in Candida albicans Yeast and Hyphal Cells, Preventing Biofilm Formation In Vitro and in a Rodent Central Venous Catheter Model.

PubMed

Ahmadi, Mohammed S; Lee, Hiu Ham; Sanchez, David A; Friedman, Adam J; Tar, Moses T; Davies, Kelvin P; Nosanchuk, Joshua D; Martinez, Luis R

2016-04-01

Candida albicansis a leading nosocomial pathogen. Today, candidal biofilms are a significant cause of catheter infections, and such infections are becoming increasingly responsible for the failure of medical-implanted devices.C. albicansforms biofilms in which fungal cells are encased in an autoproduced extracellular polysaccharide matrix. Consequently, the enclosed fungi are protected from antimicrobial agents and host cells, providing a unique niche conducive to robust microbial growth and a harbor for recurring infections. Here we demonstrate that a recently developed platform comprised of nanoparticles that release therapeutic levels of nitric oxide (NO-np) inhibits candidal biofilm formation, destroys the extracellular polysaccharide matrices of mature fungal biofilms, and hinders biofilm development on surface biomaterials such as the lumen of catheters. We found NO-np to decrease both the metabolic activity of biofilms and the cell viability ofC. albicansin vitroandin vivo Furthermore, flow cytometric analysis found NO-np to induce apoptosis in biofilm yeast cellsin vitro Moreover, NO-np behave synergistically when used in combination with established antifungal drug therapies. Here we propose NO-np as a novel treatment modality, especially in combination with standard antifungals, for the prevention and/or remediation of fungal biofilms on central venous catheters and other medical devices. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

[Preliminary Investigation of the Amount, the Molecular Weight and the Activity of Polysaccharides from Chaenomeles Speciosa Fruits in Ethanol Fractional Precipitation].

PubMed

Tian, Bing-mei; Xie, Xiao-mei; Shen, Pan-pan; Yang, Mo; Zhang, Sheng-long; Tang, Qing-jiu

2015-05-01

Chaenomeles speciosa fruits were extracted using water. The extracts were precipitated with 20%~95% (φ) ethanol, respectively. The amount of total polysaccharide was measured with phenol-sulfuric acid method. A method using high-performance size-exclusion chromatography (HPSEC) equipped with multiangle laser-light-scattering photometry (MALLS) and differential refractometry (RI) was presented for determining the molecular weight and molecular weigh distribution. RAW264.7 macrophage were cultured and stimulated with the polysaccharides in vitro and the production of nitric oxide in the cells was determined by the Griess assay. The aim of the study is to determine the amount and the molecular weight of the polysaccharides from Chaenomeles speciosa fruits, and preliminary investigate the immunomodulatory activity, The study provided the basis datas for the further research of Chaenomeles speciosa fruits. , and provided a simple and system method for the research of natural polysaccharide. The ethanol fractional precipitation showed that the order of total polysaccharide content was 95%>80%>40% ≥60%>20%. The results indicated that most polysaccharide from Chaenomeles speciosa fruits might be precipitated when ethanol concentration was up to 95% (T) and the crude polysaccharide purity had risen from 35. 1% to 45. 0% when the concentration of ethanol increased from 20% to 95%. HPSEC-MALLS-RI system showed that all the polysaccharide samples had the similar compositions. They appeared three chromatographic peaks and the retention time were not apparently different. The Mw were 6. 570 X 10(4) g . mol-1 and 1. 393 X 10(4) g . mol-1 respectively, and one less than 10 000 which was failure to obtain accurate values. The molecular weight of the first two polysaccharide distribution index(Mw/Mn)were 1. 336 and 1. 639 respectively. The polysaccharide samples had not exhibited immunomodulatory activity assessed on the basis of nitric oxide production by RAW264. 7 macrophage cells in the experiment.

Polysaccharide-thickened aqueous fluoride solutions for rapid destruction of the nerve agent VX. Introducing the opportunity for extensive decontamination scenarios.

PubMed

Elias, Shlomi; Saphier, Sigal; Columbus, Ishay; Zafrani, Yossi

2014-01-01

Among the chemical warfare agents, the extremely toxic nerve agent VX (O-ethyl S-2-(diisopropylamino)ethyl methylphosphonothioate) is a target of high importance in the development of decontamination methods, due to its indefinite persistence on common environmental surfaces. Liquid decontaminants are mostly characterized by high corrosivity, usually offer poor coverage, and tend to flow and accumulate in low areas. Therefore, the development of a noncorrosive decontaminant, sufficiently viscous to resist dripping from the contaminated surface, is necessary. In the present paper we studied different polysaccharides-thickened fluoride aqueous solutions as noncorrosive decontaminants for rapid and efficient VX degradation to the nontoxic product EMPA (ethyl methylphosphonic acid). Polysaccharides are environmentally benign, natural, and inexpensive. Other known decontaminants cannot be thickened by polysaccharides, due to the sensitivity of the latter toward basic or oxidizing agents. We found that the efficiency of VX degradation in these viscous solutions in terms of kinetics and product identity is similar to that of KF aqueous solutions. Guar gum (1.5 wt %) with 4 wt % KF was chosen for further evaluation. The benign nature, rheological properties, adhering capabilities to different surfaces, and decontamination from a porous matrix were examined. This formulation showed promising properties for implementation as a spray decontaminant for common and sensitive environmental surfaces.

Cell-wall polysaccharides and glycoproteins of parenchymatous tissues of runner bean (Phaseolus coccineus).

PubMed Central

Ryden, P; Selvendran, R R

1990-01-01

1. Polymers were solubilized from the cell walls of parenchyma from mature runner-bean pods with minimum degradation by successive extractions with cyclohexane-trans-1,2-diamine-NNN'N'-tetra-acetate (CDTA), Na2CO3 and KOH to leave the alpha-cellulose residue, which contained cross-linked pectic polysaccharides and Hyp-rich glycoproteins. These were solubilized with chlorite/acetic acid and cellulase. The polymers were fractionated by anion-exchange chromatography, and fractions were subjected to methylation analysis. 2. The pectic polysaccharides differed in their ease of extraction, and a small proportion were highly cross-linked. The bulk of the pectic polysaccharides solubilized by CDTA and Na2CO3 were less branched than those solubilized by KOH. There was good evidence that most of the pectic polysaccharides were not degraded during extraction. 3. The protein-containing fractions included Hyp-rich and Hyp-poor glycoproteins associated with easily extractable pectic polysaccharides, Hyp-rich glycoproteins solubilized with 4M-KOH+borate, the bulk of which were not associated with pectic polysaccharides, and highly cross-linked Hyp-rich glycoproteins. 4. Isodityrosine was not detected, suggesting that it does not have a (major) cross-linking role in these walls. Instead, it is suggested that phenolics, presumably linked to C-5 of 3,5-linked Araf residues of Hyp-rich glycoproteins, serve to cross-link some of the polymers. 5. There were two main types of xyloglucan, with different degrees of branching. The bulk of the less branched xyloglucans were solubilized by more-concentrated alkali. The anomeric configurations of the sugars in one of the highly branched xyloglucans were determined by 13C-n.m.r. spectroscopy. 6. The structural features of the cell-wall polymers and complexes are discussed in relation to the structure of the cell walls of parenchyma tissues. PMID:2167068

Host-pathogen interactions. VII. Isolation of a pathogen-synthesized fraction rich in glucan that elicits a defense response in the pathogen's host

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

Anderson-Prouty, A.J.; Albersheim, P.

1975-01-01

A polysaccharide from the fungal pathogen Colletotrichum lindemuthianum causes browning and phytoalexin production when applied to the cut surfaces of bean (Phaseolus vulgaris) cotyledons and hypocotyls. The application of an amount of polysaccharide equivalent to less than 100 ng of glucose will elicit this response in the bean tissues. The polysaccharide has been isolated both from culture filtrates and from the mycelial walls of the fungus. Purification of the polysaccharide involved anion and cation exchange chromatography and gel filtration. The polysaccharide has an apparent molecular weight between 1,000,000 and 5,000,000 daltons, and consists predominantly of 3- and 4-linked glucosyl residues.more » (auth)« less

Cell wall evolution and diversity

PubMed Central

Fangel, Jonatan U.; Ulvskov, Peter; Knox, J. P.; Mikkelsen, Maria D.; Harholt, Jesper; Popper, Zoë A.; Willats, William G.T.

2012-01-01

Plant cell walls display a considerable degree of diversity in their compositions and molecular architectures. In some cases the functional significance of a particular cell wall type appears to be easy to discern: secondary cells walls are often reinforced with lignin that provides durability; the thin cell walls of pollen tubes have particular compositions that enable their tip growth; lupin seed cell walls are characteristically thickened with galactan used as a storage polysaccharide. However, more frequently the evolutionary mechanisms and selection pressures that underpin cell wall diversity and evolution are unclear. For diverse green plants (chlorophytes and streptophytes) the rapidly increasing availability of transcriptome and genome data sets, the development of methods for cell wall analyses which require less material for analysis, and expansion of molecular probe sets, are providing new insights into the diversity and occurrence of cell wall polysaccharides and associated biosynthetic genes. Such research is important for refining our understanding of some of the fundamental processes that enabled plants to colonize land and to subsequently radiate so comprehensively. The study of cell wall structural diversity is also an important aspect of the industrial utilization of global polysaccharide bio-resources. PMID:22783271

Isolation and characterization of polysaccharides with the antitumor activity from Tuber fruiting bodies and fermentation system.

PubMed

Zhao, Wei; Wang, Xiao-Hua; Li, Hong-Mei; Wang, Shi-Hua; Chen, Tao; Yuan, Zhan-Peng; Tang, Ya-Jie

2014-03-01

Fifty-two polysaccharides were isolated from the fermentation systems of Tuber melanosporum, Tuber indicum, Tuber sinense, Tuber aestivum and the fruiting bodies of Tuber indicum, Tuber himalayense, Tuber sinense by elution with an activated carbon column. Polysaccharides from Tuber fermentation system exhibited relatively higher in vitro antitumor activity against HepG2, A549, HCT-116, SK-BR-3, and HL-60 cells than those from Tuber fruiting bodies. All polysaccharides were mainly composed of D-mannose, D-glucose, and D-galactose, which suggested that the polysaccharides from Tuber fruiting bodies and fermentation system have identical chemical compositions. The results of antitumor activity and structural identification indicated that the polysaccharide fractions could promote antitumor activity. Tuber polysaccharides from Tuber fermentation system exhibited relatively higher than that from Tuber fruiting bodies. These results confirm the potential of Tuber fermentation mycelia for use as an alternative resource for its fruiting bodies.

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

PubMed

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

2017-02-01

In the present work, optimization of hot water extraction, structural characteristics, functional properties, and biological activities of polysaccharides extracted from watermelon rinds (WMRP) were investigated. The physicochemical characteristics and the monosaccharide composition of these polysaccharides were then determined using chemical composition analysis, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and gas chromatography-flame ionization detection (GC-FID). SEM images showed that extracted polysaccharides had a rough surface with many cavities. GC-FID results proved that galactose was the dominant sugar in the extracted polysaccharides, followed by arabinose, glucose, galacturonic acid, rhamnose, mannose, xylose and traces of glucuronic acid. The findings revealed that WMRP displayed excellent antihypertensive and antioxidant activities. Those polysaccharides had also a protection effect against hydroxyl radical-induced DNA damage. Functional properties of extracted polysaccharides were also evaluated. WMRP showed good interfacial dose-dependent proprieties. Overall, the results suggested that WMRP presents a promising natural source of antioxidants and antihypertensive agents. Copyright © 2016 Elsevier Ltd. All rights reserved.

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.

Chemical Organization of the Cell Wall Polysaccharide Core of Malassezia restricta

PubMed Central

Stalhberger, Thomas; Simenel, Catherine; Clavaud, Cécile; Eijsink, Vincent G. H.; Jourdain, Roland; Delepierre, Muriel; Latgé, Jean-Paul; Breton, Lionel; Fontaine, Thierry

2014-01-01

Malassezia species are ubiquitous residents of human skin and are associated with several diseases such as seborrheic dermatitis, tinea versicolor, folliculitis, atopic dermatitis, and scalp conditions such as dandruff. Host-Malassezia interactions and mechanisms to evade local immune responses remain largely unknown. Malassezia restricta is one of the most predominant yeasts of the healthy human skin, its cell wall has been investigated in this paper. Polysaccharides in the M. restricta cell wall are almost exclusively alkali-insoluble, showing that they play an essential role in the organization and rigidity of the M. restricta cell wall. Fractionation of cell wall polymers and carbohydrate analyses showed that the polysaccharide core of the cell wall of M. restricta contained an average of 5% chitin, 20% chitosan, 5% β-(1,3)-glucan, and 70% β-(1,6)-glucan. In contrast to other yeasts, chitin and chitosan are relatively abundant, and β-(1,3)-glucans constitute a minor cell wall component. The most abundant polymer is β-(1,6)-glucans, which are large molecules composed of a linear β-(1,6)-glucan chains with β-(1,3)-glucosyl side chain with an average of 1 branch point every 3.8 glucose unit. Both β-glucans are cross-linked, forming a huge alkali-insoluble complex with chitin and chitosan polymers. Data presented here show that M. restricta has a polysaccharide organization very different of all fungal species analyzed to date. PMID:24627479

Chemical organization of the cell wall polysaccharide core of Malassezia restricta.

PubMed

Stalhberger, Thomas; Simenel, Catherine; Clavaud, Cécile; Eijsink, Vincent G H; Jourdain, Roland; Delepierre, Muriel; Latgé, Jean-Paul; Breton, Lionel; Fontaine, Thierry

2014-05-02

Malassezia species are ubiquitous residents of human skin and are associated with several diseases such as seborrheic dermatitis, tinea versicolor, folliculitis, atopic dermatitis, and scalp conditions such as dandruff. Host-Malassezia interactions and mechanisms to evade local immune responses remain largely unknown. Malassezia restricta is one of the most predominant yeasts of the healthy human skin, its cell wall has been investigated in this paper. Polysaccharides in the M. restricta cell wall are almost exclusively alkali-insoluble, showing that they play an essential role in the organization and rigidity of the M. restricta cell wall. Fractionation of cell wall polymers and carbohydrate analyses showed that the polysaccharide core of the cell wall of M. restricta contained an average of 5% chitin, 20% chitosan, 5% β-(1,3)-glucan, and 70% β-(1,6)-glucan. In contrast to other yeasts, chitin and chitosan are relatively abundant, and β-(1,3)-glucans constitute a minor cell wall component. The most abundant polymer is β-(1,6)-glucans, which are large molecules composed of a linear β-(1,6)-glucan chains with β-(1,3)-glucosyl side chain with an average of 1 branch point every 3.8 glucose unit. Both β-glucans are cross-linked, forming a huge alkali-insoluble complex with chitin and chitosan polymers. Data presented here show that M. restricta has a polysaccharide organization very different of all fungal species analyzed to date.

Antigen processing of glycoconjugate vaccines; the polysaccharide portion of the pneumococcal CRM(197) conjugate vaccine co-localizes with MHC II on the antigen processing cell surface.

PubMed

Lai, Zengzu; Schreiber, John R

2009-05-21

Pneumococcal (Pn) polysaccharides (PS) are T-independent (TI) antigens and do not induce immunological memory or antibodies in infants. Conjugation of PnPS to the carrier protein CRM(197) induces PS-specific antibody in infants, and memory similar to T-dependent (Td) antigens. Conjugates have improved immunogenicity via antigen processing and presentation of carrier protein with MHC II and recruitment of T cell help, but the fate of the PS attached to the carrier is unknown. To determine the location of the PS component of PnPS-CRM(197) in the APC, we separately labeled PS and protein and tracked their location. The PS of types 14-CRM(197) and 19F-CRM(197) was specifically labeled by Alexa Fluor 594 hydrazide (red). The CRM(197) was separately labeled red in a reaction that did not label PS. Labeled antigens were incubated with APC which were fixed, permeabilized and incubated with anti-MHC II antibody labeled green by Alexa Fluor 488, followed by confocal microscopy. Labeled CRM(197) was presented on APC surface and co-localized with MHC II (yellow). Labeled unconjugated 14 or 19F PS did not go to the APC surface, but PS labeled 14-CRM(197) and 19F-CRM(197) was internalized and co-localized with MHC II. Monoclonal antibody to type 14 PS bound to intracellular type 14 PS and PS-CRM(197). Brefeldin A and chloroquine blocked both CRM(197) and PS labeled 14-CRM(197) and 19F-CRM(197) from co-localizing with MHC II. These data suggest that the PS component of the CRM(197) glycoconjugate enters the endosome, travels with CRM(197) peptides to the APC surface and co-localizes with MHC II.

Nanostructures Derived from Starch and Chitosan for Fluorescence Bio-Imaging

PubMed Central

Zu, Yinxue; Bi, Jingran; Yan, Huiping; Wang, Haitao; Song, Yukun; Zhu, Bei-Wei; Tan, Mingqian

2016-01-01

Fluorescent nanostructures (NSs) derived from polysaccharides have drawn great attention as novel fluorescent probes for potential bio-imaging applications. Herein, we reported a facile alkali-assisted hydrothermal method to fabricate polysaccharide NSs using starch and chitosan as raw materials. Transmission electron microscopy (TEM) demonstrated that the average particle sizes are 14 nm and 75 nm for starch and chitosan NSs, respectively. Fourier transform infrared (FT-IR) spectroscopy analysis showed that there are a large number of hydroxyl or amino groups on the surface of these polysaccharide-based NSs. Strong fluorescence with an excitation-dependent emission behaviour was observed under ultraviolet excitation. Interestingly, the photostability of the NSs was found to be superior to fluorescein and rhodamine B. The quantum yield of starch NSs could reach 11.12% under the excitation of 360 nm. The oxidative metal ions including Cu(II), Hg(II)and Fe(III) exhibited a quench effect on the fluorescence intensity of the prepared NSs. Both of the two kinds of the multicoloured NSs showed a maximum fluorescence intensity at pH 7, while the fluorescence intensity decreased dramatically when they were put in an either acidic or basic environment (at pH 3 or 11). The cytotoxicity study of starch NSs showed that low cell cytotoxicity and 80% viability was found after 24 h incubation, when their concentration was less than 10 mg/mL. The study also showed the possibility of using the multicoloured starch NSs for mouse melanoma cells and guppy fish imaging. PMID:28335258

Production of pigment-free pullulan by swollen cell in Aureobasidium pullulans NG which cell differentiation was affected by pH and nutrition.

PubMed

Li, Bing-xue; Zhang, Ning; Peng, Qing; Yin, Tie; Guan, Fei-fei; Wang, Gui-li; Li, Ying

2009-08-01

A black yeast strain "NG" was isolated from strawberry fruit and identified as Aureobasidium pullulans. Strain NG displayed yeast-like cell (YL), swollen cell (SC), septate swollen cell (SSC), meristematic structure (MS), and chlamydospore (CH) morphologies. pH was the key factor regulating cell morphogenesis of strain NG. Differentiation of YL controlled by extracellular pH had no relationship with nutrition level. YL was maintained at pH >6.0, but was transformed into SC at pH approximately 4.5. SC, a stable cell type of A. pullulans, could bud, septate, or transform into MS or CH, in response to nutrition level and low pH. SC produced swollen cell blastospores (SCB) at pH 2.1 with abundant nutrition, and could transform into MS at lower pH (1.5). SC was induced to form CH by low level nutrition and pH <3, and this transition was suppressed by adjusting pH to approximately 4.5. Crude polysaccharides without pigment (melanin) were produced by SC of strain NG. Pullulan content of the polysaccharides was very high (98.37%). Fourier-transform infrared spectroscopy confirmed that chemical structures of the polysaccharides and standard pullulan were identical. Swollen cells produced 2.08 mg/ml non-pigmented polysaccharides at 96 h in YPD medium. Controlling pH of fermentation is an effective and convenient method to harvest SC for melanin-free pullulan production.

Cellulose Structural Polymorphism in Plant Primary Cell Walls Investigated by High-Field 2D Solid-State NMR Spectroscopy and Density Functional Theory Calculations.

PubMed

Wang, Tuo; Yang, Hui; Kubicki, James D; Hong, Mei

2016-06-13

The native cellulose of bacterial, algal, and animal origins has been well studied structurally using X-ray and neutron diffraction and solid-state NMR spectroscopy, and is known to consist of varying proportions of two allomorphs, Iα and Iβ, which differ in hydrogen bonding, chain packing, and local conformation. In comparison, cellulose structure in plant primary cell walls is much less understood because plant cellulose has lower crystallinity and extensive interactions with matrix polysaccharides. Here we have combined two-dimensional magic-angle-spinning (MAS) solid-state nuclear magnetic resonance (solid-state NMR) spectroscopy at high magnetic fields with density functional theory (DFT) calculations to obtain detailed information about the structural polymorphism and spatial distributions of plant primary-wall cellulose. 2D (13)C-(13)C correlation spectra of uniformly (13)C-labeled cell walls of several model plants resolved seven sets of cellulose chemical shifts. Among these, five sets (denoted a-e) belong to cellulose in the interior of the microfibril while two sets (f and g) can be assigned to surface cellulose. Importantly, most of the interior cellulose (13)C chemical shifts differ significantly from the (13)C chemical shifts of the Iα and Iβ allomorphs, indicating that plant primary-wall cellulose has different conformations, packing, and hydrogen bonding from celluloses of other organisms. 2D (13)C-(13)C correlation experiments with long mixing times and with water polarization transfer revealed the spatial distributions and matrix-polysaccharide interactions of these cellulose structures. Celluloses f and g are well mixed chains on the microfibril surface, celluloses a and b are interior chains that are in molecular contact with the surface chains, while cellulose c resides in the core of the microfibril, outside spin diffusion contact with the surface. Interestingly, cellulose d, whose chemical shifts differ most significantly from those of bacterial, algal, and animal cellulose, interacts with hemicellulose, is poorly hydrated, and is targeted by the protein expansin during wall loosening. To obtain information about the C6 hydroxymethyl conformation of these plant celluloses, we carried out DFT calculations of (13)C chemical shifts, using the Iα and Iβ crystal structures as templates and varying the C5-C6 torsion angle. Comparison with the experimental chemical shifts suggests that all interior cellulose favor the tg conformation, but cellulose d also has a similar propensity to adopt the gt conformation. These results indicate that cellulose in plant primary cell walls, due to their interactions with matrix polysaccharides, and has polymorphic structures that are not a simple superposition of the Iα and Iβ allomorphs, thus distinguishing them from bacterial and animal celluloses.

Cellulose Structural Polymorphism in Plant Primary Cell Walls Investigated by High-Field 2D Solid-State NMR Spectroscopy and Density Functional Theory Calculations

PubMed Central

Wang, Tuo; Yang, Hui; Kubicki, James D.; Hong, Mei

2017-01-01

The native cellulose of bacterial, algal, and animal origins has been well studied structurally using X-ray and neutron diffraction and solid-state NMR spectroscopy, and is known to consist of varying proportions of two allomorphs, Iα and Iβ, which differ in hydrogen bonding, chain packing, and local conformation. In comparison, cellulose structure in plant primary cell walls is much less understood because plant cellulose has lower crystallinity and extensive interactions with matrix polysaccharides. Here we have combined two-dimensional magic-angle-spinning (MAS) solid-state nuclear magnetic resonance (solid-state NMR) spectroscopy at high magnetic fields with density functional theory (DFT) calculations to obtain detailed information about the structural polymorphism and spatial distributions of plant primary-wall cellulose. 2D 13C-13C correlation spectra of uniformly 13C-labeled cell walls of several model plants resolved seven sets of cellulose chemical shifts. Among these, five sets (denoted a-e) belong to cellulose in the interior of the microfibril while two sets (f and g) can be assigned to surface cellulose. Importantly, most of the interior cellulose 13C chemical shifts differ significantly from the 13C chemical shifts of the Iα and Iβ allomorphs, indicating that plant primary-wall cellulose has different conformations, packing and hydrogen bonding from celluloses of other organisms. 2D 13C-13C correlation experiments with long mixing times and with water polarization transfer revealed the spatial distributions and matrix-polysaccharide interactions of these cellulose structures. Cellulose f and g are well mixed chains on the microfibril surface, cellulose a and b are interior chains that are in molecular contact with the surface chains, while cellulose c resides in the core of the microfibril, outside spin diffusion contact with the surface. Interestingly, cellulose d, whose chemical shifts differ most significantly from those of bacterial, algal and animal cellulose, interacts with hemicellulose, is poorly hydrated, and is targeted by the protein expansin during wall loosening. To obtain information about the C6 hydroxymethyl conformation of these plant celluloses, we carried out DFT calculations of 13C chemical shifts, using the Iα and Iβ crystal structures as templates and varying the C5-C6 torsion angle. Comparison with the experimental chemical shifts suggests that all interior cellulose favor the tg conformation, but cellulose d also has a similar propensity to adopt the gt conformation. These results indicate that cellulose in plant primary cell walls, due to their interactions with matrix polysaccharides, has polymorphic structures that are not a simple superposition of the Iα and Iβ allomorphs, thus distinguishing them from bacterial and animal celluloses. PMID:27192562

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.

Protein secretion and surface display in Gram-positive bacteria

PubMed Central

Schneewind, Olaf; Missiakas, Dominique M.

2012-01-01

The cell wall peptidoglycan of Gram-positive bacteria functions as a surface organelle for the transport and assembly of proteins that interact with the environment, in particular, the tissues of an infected host. Signal peptide-bearing precursor proteins are secreted across the plasma membrane of Gram-positive bacteria. Some precursors carry C-terminal sorting signals with unique sequence motifs that are cleaved by sortase enzymes and linked to the cell wall peptidoglycan of vegetative forms or spores. The sorting signals of pilin precursors are cleaved by pilus-specific sortases, which generate covalent bonds between proteins leading to the assembly of fimbrial structures. Other precursors harbour surface (S)-layer homology domains (SLH), which fold into a three-pronged spindle structure and bind secondary cell wall polysaccharides, thereby associating with the surface of specific Gram-positive microbes. Type VII secretion is a non-canonical secretion pathway for WXG100 family proteins in mycobacteria. Gram-positive bacteria also secrete WXG100 proteins and carry unique genes that either contribute to discrete steps in secretion or represent distinctive substrates for protein transport reactions. PMID:22411983

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 H. pleuropneumoniae serotypes 1 and 7; however, several OMPs and the lipopolysaccharide or polysaccharide determinants of these serotypes appeared to be type specific. Images PMID:3536748

Structural studies of the O-specific polysaccharide(s) from the lipopolysaccharide of Azospirillum brasilense type strain Sp7.

PubMed

Sigida, Elena N; Fedonenko, Yuliya P; Shashkov, Alexander S; Zdorovenko, Evelina L; Konnova, Svetlana A; Ignatov, Vladimir V; Knirel, Yuriy A

2013-10-18

Lipopolysaccharide was obtained by phenol-water extraction from dried bacterial cells of Azospirillum brasilense type strain Sp7. Mild acid hydrolysis of the lipopolysaccharide followed by GPC on Sephadex G-50 resulted in a polysaccharide mixture, which was studied by composition and methylation analyses, Smith degradation and (1)H and (13)C NMR spectroscopy. The following polysaccharide structures were established, where italics indicate a non-stoichiometric (∼40%) 2-O-methylation of l-rhamnose. Copyright © 2013 Elsevier Ltd. All rights reserved.

Polysaccharide of Danggui Buxue Tang, an Ancient Chinese Herbal Decoction, Induces Expression of Pro-inflammatory Cytokines Possibly Via Activation of NFκB Signaling in Cultured RAW 264.7 Cells.

PubMed

Gong, Amy Gw; Zhang, Laura Ml; Lam, Candy Tw; Xu, Miranda L; Wang, Huai Y; Lin, H Q; Dong, Tina Tx; Tsim, Karl Wk

2017-02-01

Danggui Buxue Tang (DBT) is an ancient Chinese herbal decoction containing two herbs, Astragali Radix (AR) and Angelicae Sinensis Radix (ASR): this herbal decoction serves as dietary supplement for women during menopause. DBT has been known to modulate immune responses, and its polysaccharide is proposed to be one of the active components. However, the polysaccharide-induced signaling in immune activation is not revealed. Here, we are identifying that the immune activation, triggered by DBT, could be mediated by polysaccharide. In cultured macrophages (RAW 264.7 cells), the application of polysaccharide-enriched extract of DBT significantly increased the expressions of mRNA and protein levels of interleukin-1β, interleukin-6 and tumor necrosis factor. The induction was much stronger than the polysaccharide extract generated singly from AR, or from ASR, or from their simple mixture. The induced cytokine release in cultured macrophage was revealed to be triggered by activation of nuclear factor-kappa B (NF-κB) signaling, including (i) degradation of IkBα; (ii) translocation of NF-κB p65 from cytosol to nuclei; and (iii) activation of NF-κB transcriptional elements. These results verified the possible role of DBT polysaccharide in modulating immune responses. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A study of the native cell wall structures of the marine alga Ventricaria ventricosa (Siphonocladales, Chlorophyceae) using atomic force microscopy.

PubMed

Eslick, Enid M; Beilby, Mary J; Moon, Anthony R

2014-04-01

A substantial proportion of the architecture of the plant cell wall remains unknown with a few cell wall models being proposed. Moreover, even less is known about the green algal cell wall. Techniques that allow direct visualization of the cell wall in as near to its native state are of importance in unravelling the spatial arrangement of cell wall structures and hence in the development of cell wall models. Atomic force microscopy (AFM) was used to image the native cell wall of living cells of Ventricaria ventricosa (V. ventricosa) at high resolution under physiological conditions. The cell wall polymers were identified mainly qualitatively via their structural appearance. The cellulose microfibrils (CMFs) were easily recognizable and the imaging results indicate that the V. ventricosa cell wall has a cross-fibrillar structure throughout. We found the native wall to be abundant in matrix polysaccharides existing in different curing states. The soft phase matrix polysaccharides susceptible by the AFM scanning tip existed as a glutinous fibrillar meshwork, possibly incorporating both the pectic- and hemicellulosic-type substances. The hard phase matrix producing clearer images, revealed coiled fibrillar structures associated with CMFs, sometimes being resolved as globular structures by the AFM tip. The coiling fibrillar structures were also seen in the images of isolated cell wall fragments. The mucilaginous component of the wall was discernible from the gelatinous cell wall matrix as it formed microstructural domains over the surface. AFM has been successful in imaging the native cell wall and revealing novel findings such as the 'coiling fibrillar structures' and cell wall components which have previously not been seen, that is, the gelatinous matrix phase.

The effect of covalently linked RGD peptide on the conformation of polysaccharides in aqueous solutions.

PubMed

Bernstein-Levi, Ortal; Ochbaum, Guy; Bitton, Ronit

2016-01-01

Covalently modified polysaccharides are routinely used in tissue engineering due to their tailored biofunctionality. Understanding the effect of single-chain level modification on the solution conformation of the single chain, and more importantly on the self-assembly and aggregation of the ensemble of chains is expected to improve our ability to control network topology and the properties of the resulting gels. Attaching an RGD peptide to a polysaccharide backbone is a common procedure used to promote cell adhesion in hydrogel scaffolds. Recently it has been shown that the spatial presentation of the RGD sequences affects the cell behavior; thus, understanding the effects of grafted RGD on the conformational properties of the solvated polysaccharide chains is a prerequisite for rational design of polysaccharide-peptide based biomaterials. Here we investigate the effect of covalently linked G4RGDS on the conformational state of the individual chain and chain assemblies of alginate, chitosan, and hyaluronic acid (HA) in aqueous solutions. Two peptide fractions were studied using small-angle X-ray scattering (SAXS) and rheology. In all cases, upon peptide conjugation structural differences were observed. Analysis of the scattering data shows evidence of clustering for a higher fraction of bound peptide. Moreover for all three polysaccharides the typical shear thinning behavior of the natural polysaccharide solutions is replaced by a Newtonian fluid behavior for the lower fraction conjugated peptide while a more pronounced shear thinning behavior is observed for the higher fraction. These results indicate that the fraction of the bounded peptide, determines the behavior of a polysaccharide-peptide conjugates in solution, regardless of the specific nature of the polysaccharide. Copyright © 2015 Elsevier B.V. All rights reserved.

Selective Cytotoxic Activity of Se-Methyl-Seleno-L-Cysteine- and Se-Polysaccharide-Containing Extracts from Shiitake Medicinal Mushroom, Lentinus edodes (Agaricomycetes).

PubMed

Klimaszewska, Marzenna; Górska, Sandra; Dawidowski, Maciej; Podsadni, Piotr; Szczepanska, Agnieszka; Orzechowska, Emilia; Kurpios-Piec, Dagmara; Grosicka-Maciag, Emilia; Rahden-Staroń, Iwonna; Turło, Jadwiga

2017-01-01

Numerous formulations derived from the shiitake medicinal mushroom, Lentinus edodes, demonstrate anticancer activities. We hypothesized that isolates from selenium (Se)-enriched mycelia of L. edodes would possess stronger cancer-preventive properties than current preparations. The aim of this study was to investigate whether the presence of Se-methyl-seleno-L-cysteine in mycelial extracts of L. edodes affects their cytotoxic activity (makes them stronger) or whether they are as effective as Se-containing polysaccharides. Extracts were prepared from Se-containing mycelia under various conditions and assayed for cytotoxic activity in cancer (PC3 and HeLa) and normal (HMEC-1) cell lines. The chemical composition of the extracts was examined; specifically, the amounts of potentially cytotoxic Se compounds (methylselenocysteine, selenomethionine, and Se-containing polysaccharides) were measured. The relationship between extract composition and biological activity was characterized. Mycelial cultures were cultivated in a 10-L bioreactor in medium enriched with sodium selenite. Mycelial extracts were prepared either at 100°C or at 4°C in acidic solution. Total Se content was determined using the atomic absorption spectrometry method, and methylselenocysteine and selenomethionine contents were measured using reverse-phase high-performance liquid chromatography. Protein, carbohydrate, and polyphenolic contents were determined with spectrophotometric methods, and Se-containing polysaccharides were measured with the use of precipitation. Anticancer activity of mycelial extracts was examined using the MTT cell viability assay. Extracts containing Se-methyl-seleno-L-cysteine or Se-polysaccharides prepared at 4°C and 100°C, respectively, display moderate, time-dependent, specific cytotoxic activity in HeLa and PC3 cell lines. The effect in HeLa cells is more pronounced in the extract prepared at 4°C than at 100°C. The effect is almost equal for the PC3 cell line. However, both extracts have no effect or only slightly stimulate normal (HMEC-1) cell viability. The selective cytotoxic activity of L. edodes extracts in cancer (PC3 and HeLa) cells is due to the presence of both Se-methyl-seleno-L-cysteine and selenated polysaccharides, perhaps in combination with other active ingredients.

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 polysaccharides in the high Arctic open lead SML.

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.

2012-01-01

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 and dissolved organic matter (POM, DOM) 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 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. Experimentally-generated aerosol particles were enriched in polysaccharides by factors of 22-70, relative to the source seawater. We propose that bubble scavenging of surface-active polysaccharides was one of the possible mechanisms for the enrichment of polysaccharides in the SML.

Changes in cell wall polysaccharide composition, gene transcription and alternative splicing in germinating barley embryos.

PubMed

Zhang, Qisen; Zhang, Xiaoqi; Pettolino, Filomena; Zhou, Gaofeng; Li, Chengdao

2016-02-01

Barley (Hordeum vulgare L.) seed germination initiates many important biological processes such as DNA, membrane and mitochondrial repairs. However, little is known on cell wall modifications in germinating embryos. We have investigated cell wall polysaccharide composition change, gene transcription and alternative splicing events in four barley varieties at 24h and 48 h germination. Cell wall components in germinating barley embryos changed rapidly, with increases in cellulose and (1,3)(1,4)-β-D-glucan (20-100%) within 24h, but decreases in heteroxylan and arabinan (3-50%). There were also significant changes in the levels of type I arabinogalactans and heteromannans. Alternative splicing played very important roles in cell wall modifications. At least 22 cell wall transcripts were detected to undergo either alternative 3' splicing, alternative 5' splicing or intron retention type of alternative splicing. These genes coded enzymes catalyzing synthesis and degradation of cellulose, heteroxylan, (1,3)(1,4)-β-D-glucan and other cell wall polymers. Furthermore, transcriptional regulation also played very important roles in cell wall modifications. Transcript levels of primary wall cellulase synthase, heteroxylan synthesizing and nucleotide sugar inter-conversion genes were very high in germinating embryos. At least 50 cell wall genes changed transcript levels significantly. Expression patterns of many cell wall genes coincided with changes in polysaccharide composition. Our data showed that cell wall polysaccharide metabolism was very active in germinating barley embryos, which was regulated at both transcriptional and post-transcriptional levels. Copyright © 2015 Elsevier GmbH. All rights reserved.

Pleurotus citrinopileatus polysaccharide induces activation of human dendritic cells through multiple pathways.

PubMed

Minato, Ken-Ichiro; Laan, Lisa C; Ohara, Akihiro; van Die, Irma

2016-11-01

Many edible mushrooms have become attractive as "health foods" and as source materials for immunomodulators. To increase our insight in the immune-modulatory properties of a polysaccharide of the oyster mushroom Pleurotus citrinopileatus, PCPS, we analyzed its effects on the function of human dendritic cells (DCs). We showed that PCPS induces upregulation of the surface maturation markers CD80, CD86 and HLA-DR on DCs, indicating its potential to induce DC maturation. In addition, PCPS stimulates DCs to secrete the pro-inflammatory cytokines TNF, IL-1β, IL-6 and IL-12, as well as the anti-inflammatory cytokine IL-10, and induces enhanced mRNA levels of the chemokines CCL2, CCL3, CCL8, CXCL9, CXCL10, and LTA. The secretion of TNF and IL-12 by PCPS-activated DCs could significantly be decreased by an anti-Dectin-1 antibody, as well as by a Syk kinase and a Raf-1 inhibitor, indicating that PCPS induces Dectin-1 signaling at least partly through the Syk- and the Raf-1-dependent pathways in DCs. Structural analysis of PCPS suggests that this polysaccharide is a β-1,3-branched β-1,6-glucan, which is in line with its capacity to activate Dectin-1. We showed that PCPS can induce TLR2 and TLR4, but not TLR3, signaling using TLR-HEK293 reporter cell lines. In human DCs, the effect of PCPS was additively increased by TLR4 activation, and synergistically enhanced by stimulation of TLR2, suggesting that interaction of PCPS with these TLRs contributes to the observed DC modulation. In conclusion, PCPS has the capacity to activate human DCs via multiple pathways. Copyright © 2016 Elsevier B.V. All rights reserved.

A Selenium-Modified Ginseng Polysaccharide Promotes the Apoptosis in Human Promyelocytic Leukemia (HL-60) Cells via a Mitochondrial-Mediated Pathway.

PubMed

Liao, Kainan; Bian, Zedong; Xie, Dongke; Peng, Qiang

2017-05-01

A ginseng polysaccharide was extracted, purified, and modified by nitric acid-selenious acid (HNO 3 -H 2 SeO 3 ) method to yield one selenylation-modified polysaccharide (sGP). We reported for the first time the anticancer potential of sGP on the human promyelocytic leukemia HL-60 cell line and evaluated its relevant underlying mechanism. Our results showed that sGP markedly inhibited the growth of HL-60 cells via induction of apoptosis. The event of apoptosis was accompanied by the formation of apoptotic bodies; the release of cytochrome c; loss of mitochondrial membrane potential; and activation of caspase-9, caspase-3, and cleavage of poly ADP ribose polymerase (PARP) in HL-60 cells. In addition, western blot analysis showed that sGP inhibited antiapoptotic Bcl-2 protein expression and increased proapoptotic Bax protein expression in cells under identical conditions. Together, our study suggests that sGP induces apoptosis of HL-60 cells through the mitochondrial-dependent pathway.

Antibiofilm Activity of an Exopolysaccharide from Marine Bacterium Vibrio sp. QY101

PubMed Central

Han, Feng; Duan, Gaofei; Lu, Xinzhi; Gu, Yuchao; Yu, Wengong

2011-01-01

Bacterial exopolysaccharides have always been suggested to play crucial roles in the bacterial initial adhesion and the development of complex architecture in the later stages of bacterial biofilm formation. However, Escherichia coli group II capsular polysaccharide was characterized to exert broad-spectrum biofilm inhibition activity. In this study, we firstly reported that a bacterial exopolysaccharide (A101) not only inhibits biofilm formation of many bacteria but also disrupts established biofilm of some strains. A101 with an average molecular weight of up to 546 KDa, was isolated and purified from the culture supernatant of the marine bacterium Vibrio sp. QY101 by ethanol precipitation, iron-exchange chromatography and gel filtration chromatography. High performance liquid chromatography traces of the hydrolyzed polysaccharides showed that A101 is primarily consisted of galacturonic acid, glucuronic acid, rhamnose and glucosamine. A101 was demonstrated to inhibit biofilm formation by a wide range of Gram-negative and Gram-positive bacteria without antibacterial activity. Furthermore, A101 displayed a significant disruption on the established biofilm produced by Pseudomonas aeruginosa, but not by Staphylococcus aureus. Importantly, A101 increased the aminoglycosides antibiotics' capability of killing P. aeruginosa biofilm. Cell primary attachment to surfaces and intercellular aggregates assays suggested that A101 inhibited cell aggregates of both P. aeruginosa and S. aureus, while the cell-surface interactions inhibition only occurred in S. aureus, and the pre-formed cell aggregates dispersion induced by A101 only occurred in P. aeruginosa. Taken together, these data identify the antibiofilm activity of A101, which may make it potential in the design of new therapeutic strategies for bacterial biofilm-associated infections and limiting biofilm formation on medical indwelling devices. The found of A101 antibiofilm activity may also promote a new recognition about the functions of bacterial exopolysaccharides. PMID:21490923

Genetic and environmental factors contribute to variation in cell wall composition in mature desi chickpea (Cicer arietinum L.) cotyledons.

PubMed

Wood, Jennifer A; Tan, Hwei-Ting; Collins, Helen M; Yap, Kuok; Khor, Shi Fang; Lim, Wai Li; Xing, Xiaohui; Bulone, Vincent; Burton, Rachel A; Fincher, Geoffrey B; Tucker, Matthew R

2018-03-13

Chickpea (Cicer arietinum L.) is an important nutritionally rich legume crop that is consumed worldwide. Prior to cooking, desi chickpea seeds are most often dehulled and cleaved to release the split cotyledons, referred to as dhal. Compositional variation between desi genotypes has a significant impact on nutritional quality and downstream processing, and this has been investigated mainly in terms of starch and protein content. Studies in pulses such as bean and lupin have also implicated cell wall polysaccharides in cooking time variation, but the underlying relationship between desi chickpea cotyledon composition and cooking performance remains unclear. Here, we utilized a variety of chemical and immunohistological assays to examine details of polysaccharide composition, structure, abundance, and location within the desi chickpea cotyledon. Pectic polysaccharides were the most abundant cell wall components, and differences in monosaccharide and glycosidic linkage content suggest both environmental and genetic factors contribute to cotyledon composition. Genotype-specific differences were identified in arabinan structure, pectin methylesterification, and calcium-mediated pectin dimerization. These differences were replicated in distinct field sites and suggest a potentially important role for cell wall polysaccharides and their underlying regulatory machinery in the control of cooking time in chickpea. © 2018 The Authors. Plant, Cell & Environment Published by John Wiley & Sons Ltd.

Genetic engineering of grass cell wall polysaccharides for biorefining.

PubMed

Bhatia, Rakesh; Gallagher, Joe A; Gomez, Leonardo D; Bosch, Maurice

2017-09-01

Grasses represent an abundant and widespread source of lignocellulosic biomass, which has yet to fulfil its potential as a feedstock for biorefining into renewable and sustainable biofuels and commodity chemicals. The inherent recalcitrance of lignocellulosic materials to deconstruction is the most crucial limitation for the commercial viability and economic feasibility of biomass biorefining. Over the last decade, the targeted genetic engineering of grasses has become more proficient, enabling rational approaches to modify lignocellulose with the aim of making it more amenable to bioconversion. In this review, we provide an overview of transgenic strategies and targets to tailor grass cell wall polysaccharides for biorefining applications. The bioengineering efforts and opportunities summarized here rely primarily on (A) reprogramming gene regulatory networks responsible for the biosynthesis of lignocellulose, (B) remodelling the chemical structure and substitution patterns of cell wall polysaccharides and (C) expressing lignocellulose degrading and/or modifying enzymes in planta. It is anticipated that outputs from the rational engineering of grass cell wall polysaccharides by such strategies could help in realizing an economically sustainable, grass-derived lignocellulose processing industry. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

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.

Streptococcus gordonii DL1 adhesin SspB V-region mediates coaggregation via receptor polysaccharide of Actinomyces oris T14V.

PubMed

Back, C R; Douglas, S K; Emerson, J E; Nobbs, A H; Jenkinson, H F

2015-10-01

Streptococcus gordonii SspA and SspB proteins, members of the antigen I/II (AgI/II) family of Streptococcus adhesins, mediate adherence to cysteine-rich scavenger glycoprotein gp340 and cells of other oral microbial species. In this article we investigated further the mechanism of coaggregation between S. gordonii DL1 and Actinomyces oris T14V. Previous mutational analysis of S. gordonii suggested that SspB was necessary for coaggregation with A. oris T14V. We have confirmed this by showing that Lactococcus lactis surrogate host cells expressing SspB coaggregated with A. oris T14V and PK606 cells, while L. lactis cells expressing SspA did not. Coaggregation occurred independently of expression of A. oris type 1 (FimP) or type 2 (FimA) fimbriae. Polysaccharide was prepared from cells of A. oris T14V and found to contain 1,4-, 4,6- and 3,4-linked glucose, 1,4-linked mannose, and 2,4-linked galactose residues. When immobilized onto plastic wells this polysaccharide supported binding of L. lactis expressing SspB, but not binding of L. lactis expressing other AgI/II family proteins. Purified recombinant NAVP region of SspB, comprising amino acid (aa) residues 41-847, bound A. oris polysaccharide but the C-domain (932-1470 aa residues) did not. A site-directed deletion of 29 aa residues (Δ691-718) close to the predicted binding cleft within the SspB V-region ablated binding of the NAVP region to polysaccharide. These results infer that the V-region head of SspB recognizes an actinomyces polysaccharide ligand, so further characterizing a lectin-like coaggregation mechanism occurring between two important primary colonizers. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The dietary polysaccharide maltodextrin promotes Salmonella survival and mucosal colonization in mice.

PubMed

Nickerson, Kourtney P; Homer, Craig R; Kessler, Sean P; Dixon, Laura J; Kabi, Amrita; Gordon, Ilyssa O; Johnson, Erin E; de la Motte, Carol A; McDonald, Christine

2014-01-01

In the latter half of the 20th century, societal and technological changes led to a shift in the composition of the American diet to include a greater proportion of processed, pre-packaged foods high in fat and carbohydrates, and low in dietary fiber (a "Western diet"). Over the same time period, there have been parallel increases in Salmonella gastroenteritis cases and a broad range of chronic inflammatory diseases associated with intestinal dysbiosis. Several polysaccharide food additives are linked to bacterially-driven intestinal inflammation and may contribute to the pathogenic effects of a Western diet. Therefore, we examined the effect of a ubiquitous polysaccharide food additive, maltodextrin (MDX), on clearance of the enteric pathogen Salmonella using both in vitro and in vivo infection models. When examined in vitro, murine bone marrow-derived macrophages exposed to MDX had altered vesicular trafficking, suppressed NAPDH oxidase expression, and reduced recruitment of NADPH oxidase to Salmonella-containing vesicles, which resulted in persistence of Salmonella in enlarged Rab7+ late endosomal vesicles. In vivo, mice consuming MDX-supplemented water had a breakdown of the anti-microbial mucous layer separating gut bacteria from the intestinal epithelium surface. Additionally, oral infection of these mice with Salmonella resulted in increased cecal bacterial loads and enrichment of lamina propria cells harboring large Rab7+ vesicles. These findings indicate that consumption of processed foods containing the polysaccharide MDX contributes to suppression of intestinal anti-microbial defense mechanisms and may be an environmental priming factor for the development of chronic inflammatory disease.

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

Tolbert, Allison K.; Young, Jenna M.; Jung, Seokwon

Caldicellulosiruptor bescii is a thermophilic, anaerobic bacterium that is capable of utilizing unpretreated biomass in addition to breaking down cellulose and hemicellulose into simple sugars. Despite the fact that C. bescii must first bind to the surface of the biomass, there has been no analysis of the morphological or chemical changes to the biomass surface as a result of incubation with the micro-organism. To understand more about C. bescii growth, juvenile poplar stems were sectioned (80 μm thick) and incubated with C. bescii beyond the typical 24 h experiment length. Monitoring the cell counts during incubation revealed a biphasic growthmore » pattern. The impact the micro-organism had on the surface was determined by scanning electron microscopy (SEM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS), which showed physical crevices in the cell wall caused by the C. bescii along with a decrease of polysaccharide ions and an increase in lignin ions on the poplar surface. Employing infrared microspectroscopy, the decreasing trend was corroborated.« less

Antioxidative Dietary Compounds Modulate Gene Expression Associated with Apoptosis, DNA Repair, Inhibition of Cell Proliferation and Migration

PubMed Central

Wang, Likui; Gao, Shijuan; Jiang, Wei; Luo, Cheng; Xu, Maonian; Bohlin, Lars; Rosendahl, Markus; Huang, Wenlin

2014-01-01

Many dietary compounds are known to have health benefits owing to their antioxidative and anti-inflammatory properties. To determine the molecular mechanism of these food-derived compounds, we analyzed their effect on various genes related to cell apoptosis, DNA damage and repair, oxidation and inflammation using in vitro cell culture assays. This review further tests the hypothesis proposed previously that downstream products of COX-2 (cyclooxygenase-2) called electrophilic oxo-derivatives induce antioxidant responsive elements (ARE), which leads to cell proliferation under antioxidative conditions. Our findings support this hypothesis and show that cell proliferation was inhibited when COX-2 was down-regulated by polyphenols and polysaccharides. Flattened macrophage morphology was also observed following the induction of cytokine production by polysaccharides extracted from viili, a traditional Nordic fermented dairy product. Coix lacryma-jobi (coix) polysaccharides were found to reduce mitochondrial membrane potential and induce caspase-3- and 9-mediated apoptosis. In contrast, polyphenols from blueberries were involved in the ultraviolet-activated p53/Gadd45/MDM2 DNA repair system by restoring the cell membrane potential. Inhibition of hypoxia-inducible factor-1 by saponin extracts of ginsenoside (Ginsen) and Gynostemma and inhibition of S100A4 by coix polysaccharides inhibited cancer cell migration and invasion. These observations suggest that antioxidants and changes in cell membrane potential are the major driving forces that transfer signals through the cell membrane into the cytosol and nucleus, triggering gene expression, changes in cell proliferation and the induction of apoptosis or DNA repair. PMID:25226533

Tubulin perturbation leads to unexpected cell wall modifications and affects stomatal behaviour in Populus

DOE PAGES

Swamy, Prashant S.; Hu, Hao; Pattathil, Sivakumar; ...

2015-08-05

Cortical microtubules are integral to plant morphogenesis, cell wall synthesis, and stomatal behaviour, presumably by governing cellulose microfibril orientation. Genetic manipulation of tubulins often leads to abnormal plant development, making it difficult to probe additional roles of cortical microtubules in cell wall biogenesis. Here, it is shown that expressing post-translational C-terminal modification mimics of α-tubulin altered cell wall characteristics and guard cell dynamics in transgenic Populus tremula x alba that otherwise appear normal. 35S promoter-driven transgene expression was high in leaves but unusually low in xylem, suggesting high levels of tubulin transgene expression were not tolerated in wood-forming tissues duringmore » regeneration of transformants. Cellulose, hemicellulose, and lignin contents were unaffected in transgenic wood, but expression of cell wall-modifying enzymes, and extractability of lignin-bound pectin and xylan polysaccharides were increased in developing xylem. The results suggest that pectin and xylan polysaccharides deposited early during cell wall biogenesis are more sensitive to subtle tubulin perturbation than cellulose and matrix polysaccharides deposited later. Tubulin perturbation also affected guard cell behaviour, delaying drought-induced stomatal closure as well as light-induced stomatal opening in leaves. Pectins have been shown to confer cell wall flexibility critical for reversible stomatal movement, and results presented here are consistent with microtubule involvement in this process. In conclusion, taken together, the data show the value of growth-compatible tubulin perturbations for discerning microtubule functions, and add to the growing body of evidence for microtubule involvement in non-cellulosic polysaccharide assembly during cell wall biogenesis.« less

Structural characterization and immunomodulatory effects of polysaccharides from Phellinus linteus and Phellinus igniarius on the IL-6/IL-10 cytokine balance of the mouse macrophage cell lines (RAW 264.7).

PubMed

Suabjakyong, Papawee; Nishimura, Kazuhiro; Toida, Toshihiko; Van Griensven, Leo J L D

2015-08-01

Phellinus linteus and igniarius (L.) Quel. have been used in traditional Asian medicine for over two centuries against a variety of diseases. Polysaccharides from their fruiting bodies show strong immunomodulatory activity. In this study we characterized the structure and composition of polysaccharides from Phellinus linteus and Phellinus igniarius by HPLC, GC-MS and NMR (1-H, 13-C, COSY, NOESY and TOCSY). The polysaccharides from P. linteus and P. igniarius mainly contained glucose with minor proportions of mannose, galactose, xylose, arabinose and rhamnose. Methylation analyses showed that the glycosidic linkages were mostly 1 → 3, 1 → 6 or 1 → 3,6. The two-dimensional COSY, NOESY and TOCSY confirmed that these polysaccharides have a main chain of →3)-β-D-Glcp-(1→ with →6)-β-D-Glcp-(1→ side chain. In vitro assays by RT-PCR and ELISA showed that (1 → 3; 1 → 6)-β-D-polysaccharides from P. linteus and P. igniarius decreased TNF-α in RAW 264.7 cells, suggesting an immuno-suppressive activity. Furthermore, these polysaccharides stimulated a high IL-10 response and induced strong suppression of transcription of IL-6. The results suggest that polysaccharides from P. linteus and P. igniarius could possibly find applications in restoring the IL-6/IL-10 balance, the disturbance of which is thought to be related to chronic inflammatory disease, obesity, diabetes type 2, and to mania and depression.

Isolation and chemical characterization of dissolved and particulate polysaccharides in Mikawa Bay

NASA Astrophysics Data System (ADS)

Sakugawa, Hiroshi; Handa, Nobuhiko

1985-05-01

Isolation and chemical elucidation of dissolved and particulate polysaccharides in seawater were conducted. The water samples were collected in Mikawa Bay, Japan during a red tide bloom of the dinoflagellate, Prorocentrum minimum. Dissolved polysaccharides were concentrated from 5-101 of seawater with dialysis followed by separation by gel flitration, and isolation by ethanol precipitation. A heteropolysaccharide consisting of glucose, galactose, mannose, xylose, arabinose, fucose and rhamnose and a glucan were isolated from the polysaccharide component having a molecular weight more than 4,000 Dalton and were characterized by several chemical analyses. The heteropolysaccharide is a mucilaginous polysaccharide having a highly branched structure and a molecular weight of 10 4-5 × 10 6 Daltons and probably contains a sulfate half ester: the glucan is a polysaccharide with β-1,3- and 1,6-linkages (chrysolaminaran type). Concentrations of these were respectively ca. 20 and 67 μg l -1 at 1 m, and 2 and 26 μg l -1 at 6 m. A similar heteropolysaccharide was found in the boiling water extract of the particulate matter, while β-glucan was isolated in a much less purified form than the seawater β-glucan. In addition, a large amount of β-1,4 glucan was found in the strong alkali extract of the particulate matter, indicating that this glucan must be a cell wall polysaccharide derived from phytoplankton. These results strongly suggest that the heteropolysaccharide and chrysolaminaran type polysaccharide dissolved in seawater were derived from water soluble carbohydrates of phytoplankton through extracellular release or cell lysis.

Polysaccharide-derived mesoporous materials (Starbon®) for sustainable separation of complex mixtures.

PubMed

Zuin, Vânia G; Budarin, Vitaliy L; De Bruyn, Mario; Shuttleworth, Peter S; Hunt, Andrew J; Pluciennik, Camille; Borisova, Aleksandra; Dodson, Jennifer; Parker, Helen L; Clark, James H

2017-09-21

The recovery and separation of high value and low volume extractives are a considerable challenge for the commercial realisation of zero-waste biorefineries. Using solid-phase extractions (SPE) based on sustainable sorbents is a promising method to enable efficient, green and selective separation of these complex extractive mixtures. Mesoporous carbonaceous solids derived from renewable polysaccharides are ideal stationary phases due to their tuneable functionality and surface structure. In this study, the structure-separation relationships of thirteen polysaccharide-derived mesoporous materials and two modified types as sorbents for ten naturally-occurring bioactive phenolic compounds were investigated. For the first time, a comprehensive statistical analysis of the key molecular and surface properties influencing the recovery of these species was carried out. The obtained results show the possibility of developing tailored materials for purification, separation or extraction, depending on the molecular composition of the analyte. The wide versatility and application span of these polysaccharide-derived mesoporous materials offer new sustainable and inexpensive alternatives to traditional silica-based stationary phases.

Polysaccharide extraction from Sphallerocarpus gracilis roots by response surface methodology.

PubMed

Ma, Tingting; Sun, Xiangyu; Tian, Chengrui; Luo, Jiyang; Zheng, Cuiping; Zhan, Jicheng

2016-07-01

The extraction process of Sphallerocarpus gracilis root polysaccharides (SGRP) was optimized using response surface methodology with two methods [hot-water extraction (HWE) and ultrasonic-assisted extraction (UAE)]. The antioxidant activities of SGRP were determined, and the structural features of the untreated materials (HWE residue and UAE residue) and the extracted polysaccharides were compared by scanning electron microscopy. Results showed that the optimal UAE conditions were extraction temperature of 81°C, extraction time of 1.7h, liquid-solid ratio of 17ml/g, ultrasonic power of 300W and three extraction cycles. The optimal HWE conditions were 93°C extraction temperature, 3.6h extraction time, 21ml/g liquid-solid ratio and three extraction cycles. UAE offered a higher extraction yield with a shorter time, lower temperature and a lower solvent consumption compared with HWE, and the extracted polysaccharides possessed a higher antioxidant capacity. Therefore, UAE could be used as an alternative to conventional HWE for SGRP extraction. Copyright © 2016 Elsevier B.V. All rights reserved.

Optimization extraction of polysaccharide from Tunisian Zizyphus lotus fruit by response surface methodology: Composition and antioxidant activity.

PubMed

Mkadmini Hammi, Khaoula; Hammami, Majdi; Rihouey, Christophe; Le Cerf, Didier; Ksouri, Riadh; Majdoub, Hatem

2016-12-01

Response surface methodology using a Box-Behnken design was employed to optimize extraction temperature, extraction time and ratio of water to material to obtain a maximum polysaccharide yield with high uronic acid content and antioxidant property from edible Zizyphus lotus fruit. The optimal conditions were: extraction time of 3h 15min, extraction temperature of 91.2°C and water to solid ratio of 39mL/g. Under these conditions, the experimental extraction yield, uronic acid content and 2,2-diphenyl-1-picrylhydrazyl scavenging ability (IC50) were 18.88%, 41.89 and 0.518mg/mL, respectively. Chemical analysis revealed that the extract was composed of 97.92% carbohydrate of which 41.89% is uronic acid. The extracted polysaccharides, with an average molecular weight of 2720kDa, are composed of arabinose, rhamnose, glucose, fructose, galactose and xylose. Moreover, the polysaccharides exhibited a significant reducing power and anti-lipid peroxidation activities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mast cell activation by group A streptococcal polysaccharide in the rat and its role in experimental arthritis.

PubMed Central

Dalldorf, F. G.; Anderle, S. K.; Brown, R. R.; Schwab, J. H.

1988-01-01

Acute edematous responses were induced in Sprague-Dawley rats by the intravenous injection of group-specific polysaccharide (PS) isolated from group A streptococci. Thirty minutes after the intravenous injection of PS there was marked degranulation of subcutaneous and periarticular mast cells in all 4 feet, carbon particle labeling of adjacent venules, and an 8-fold increase in Evans blue dye content of the extremities. This acute reaction to PS was completely blocked by pretreatment with compound 48/80, but the polyarticular relapsing arthritis following the systemic injection of an arthropathic dose of streptococcal cell wall fragments containing large, covalently bound peptidoglycan-polysaccharide (PG-PS) was not blocked. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:3041843

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.

Antiviral Activities of Sulfated Polysaccharides Isolated from Sphaerococcus coronopifolius (Rhodophytha, Gigartinales) and Boergeseniella thuyoides (Rhodophyta, Ceramiales)

PubMed Central

Bouhlal, Rhimou; Haslin, Camille; Chermann, Jean-Claude; Colliec-Jouault, Sylvia; Sinquin, Corinne; Simon, Gaelle; Cerantola, Stephane; Riadi, Hassane; Bourgougnon, Nathalie

2011-01-01

Water-soluble sulfated polysaccharides isolated from two red algae Sphaerococcus coronopifolius (Gigartinales, Sphaerococcaceae) and Boergeseniella thuyoides (Ceramiales, Rhodomelaceae) collected on the coast of Morocco inhibited in vitro replication of the Human Immunodeficiency Virus (HIV) at 12.5 μg/mL. In addition, polysaccharides were capable of inhibiting the in vitro replication of Herpes simplex virus type 1 (HSV-1) on Vero cells values of EC50 of 4.1 and 17.2 μg/mL, respectively. The adsorption step of HSV-1 to the host cell seems to be the specific target for polysaccharide action. While for HIV-1, these results suggest a direct inhibitory effect on HIV-1 replication by controlling the appearance of the new generations of virus and potential virucidal effect. The polysaccharides from S. coronopifolius (PSC) and B. thuyoides (PBT) were composed of galactose, 3,6-anhydrogalactose, uronics acids, sulfate in ratios of 33.1, 11.0, 7.7 and 24.0% (w/w) and 25.4, 16.0, 3.2, 7.6% (w/w), respectively. PMID:21822410

The immunomodulatory activities of licorice polysaccharides (Glycyrrhiza uralensis Fisch.) in CT 26 tumor-bearing mice.

PubMed

Ayeka, Peter Amwoga; Bian, YuHong; Githaiga, Peter Mwitari; Zhao, Ying

2017-12-15

The increasing use of complementary and alternative medicine (CAM) has kindled the need for scientific evaluation of the mechanism of action of CAMs. Although, licorice, a common ingredient in many Traditional Chinese medicine (TCM) has attracted great attention for its antitumor and immunomodulatory activities, the mechanism of action of its polysaccharides is still unclear. Here we report the immunomodulatory activity of licorice polysaccharides in vivo. The differential anticancer activities of licorice polysaccharides by tumorigenesis and immunomodulation was evaluated in vivo. Six weeks old, 120 CT-26 tumor bearing BALB/c mice, weighing 20 ± 2 g were used. They were randomly divided into six groups, three groups receiving high molecular weight (fraction A), low molecular weight (fraction B) polysaccharides and crude extract (fraction C); positive, negative and normal groups receiving cytoxin, saline and normal diet respectively. Weight of mice and tumors was determined and tumorigenicity assay calculated to determine the anticancer effects. Immunomodulatory potential was determined by immune organ indices, immune cell population and serum cytokine levels using immune organ weight and index, flow cytometry and cytokine/chemokine bead panel kit respectively. Licorice polysaccharides exhibited immunomodulatory activities in CT 26 tumor bearing BALB/c mice. The polysaccharides significantly suppressed tumor growth and increased immune organ index. Furthermore, the immunomodulatory effect was evident with activation of CD4 + and CD8 + immune cells population. The polysaccharides also affected the production of various cytokines, by increasing IL 2, IL 6, IL 7 levels and a decreasing TNFα levels. In summary, licorice polysaccharide especially of low molecular weight exhibit anticancer and immunomodulatory activities by suppressing tumor growth and improving general health of mice. They also augment the thymus/spleen index and population of T lymphocytes. Furthermore, the polysaccharides enhance the levels of serum antitumor cytokines, IL 2, IL 6 and IL 7 while decreasing pro-tumor cytokine TNFα.

Polysaccharide nano-vesicular multidrug carriers for synergistic killing of cancer cells

NASA Astrophysics Data System (ADS)

Pramod, P. S.; Shah, Ruchira; Chaphekar, Sonali; Balasubramanian, Nagaraj; Jayakannan, Manickam

2014-09-01

Multi-drug delivery based on polymer nano-scaffolds is an essential protocol to be developed for better administration of anticancer drugs to enhance their therapeutic efficacies against cancer cells. Here, we report dual delivery polysaccharide nano-vesicles that are capable of loading and delivering both water soluble and water insoluble drugs together in a single polymer scaffold. The selective rupture of the nano-vesicular assembly under intracellular enzyme conditions allowed the simultaneous delivery of a hydrophobic drug camptothecin (CPT) and hydrophilic drug doxorubicin (DOX) supporting their synergistic killing of breast and colon cancer cells. The polysaccharide nano-vesicles have allowed us to address a few important questions regarding the need for multiple drug administration in cancer cells including (a) the role of simultaneous drug release, (b) antagonistic versus synergistic effects of drug combinations and (c) how these are affected by the ratio of drugs. Further, evaluation of the role of caveolae in endocytosis of these polymer scaffolds was also made. The vesicular scaffolds were found to preserve and deliver DOX resulting in 50-60% better killing of cancer cells than the free drug. Additionally, dual loaded nano-vesicles when compared to drug cocktails with individual drugs in separate nano-vesicles (at comparable molar ratios) suggest the relative drug concentration following release and mode of delivery to be both important in cancer cell killing. Results from these experiments have revealed newly developed polysaccharide nano-vesicles loaded with DOX and CPT drugs as potential candidates for improved breast cancer cell killing. Thus, these custom-designed polysaccharide nano-vesicles provide a new perspective on multi-anticancer drug delivery systems and their efficacy.Multi-drug delivery based on polymer nano-scaffolds is an essential protocol to be developed for better administration of anticancer drugs to enhance their therapeutic efficacies against cancer cells. Here, we report dual delivery polysaccharide nano-vesicles that are capable of loading and delivering both water soluble and water insoluble drugs together in a single polymer scaffold. The selective rupture of the nano-vesicular assembly under intracellular enzyme conditions allowed the simultaneous delivery of a hydrophobic drug camptothecin (CPT) and hydrophilic drug doxorubicin (DOX) supporting their synergistic killing of breast and colon cancer cells. The polysaccharide nano-vesicles have allowed us to address a few important questions regarding the need for multiple drug administration in cancer cells including (a) the role of simultaneous drug release, (b) antagonistic versus synergistic effects of drug combinations and (c) how these are affected by the ratio of drugs. Further, evaluation of the role of caveolae in endocytosis of these polymer scaffolds was also made. The vesicular scaffolds were found to preserve and deliver DOX resulting in 50-60% better killing of cancer cells than the free drug. Additionally, dual loaded nano-vesicles when compared to drug cocktails with individual drugs in separate nano-vesicles (at comparable molar ratios) suggest the relative drug concentration following release and mode of delivery to be both important in cancer cell killing. Results from these experiments have revealed newly developed polysaccharide nano-vesicles loaded with DOX and CPT drugs as potential candidates for improved breast cancer cell killing. Thus, these custom-designed polysaccharide nano-vesicles provide a new perspective on multi-anticancer drug delivery systems and their efficacy. Electronic supplementary information (ESI) available: Synthesis scheme, DLS histogram, FE-SEM image, AFM image, TEM image of DEX-PDP-5, AFM image of VDOX+CPT, AFM image of VDOX, characterization of VCPT, characterization of VRHO, DOX nuclear localization, characterization of dual drug loaded vesicles, fluorescent microscopic image of VDOX-CPT, cumulative drug release profile from dual drug loaded vesicles, rate constant determination, and cumulative release profile of DOX and CPT from VDOX+CPT (1 : 4). See DOI: 10.1039/c4nr03514c

In vitro and in vivo antioxidant activities of polysaccharide purified from aloe vera (Aloe barbadensis) gel.

PubMed

Kang, Min-Cheol; Kim, Seo Young; Kim, Yoon Taek; Kim, Eun-A; Lee, Seung-Hong; Ko, Seok-Chun; Wijesinghe, W A J P; Samarakoon, Kalpa W; Kim, Young-Sun; Cho, Jin Hun; Jang, Hyeang-Su; Jeon, You-Jin

2014-01-01

The in vitro and in vivo antioxidant potentials of a polysaccharide isolated from aloe vera gel were investigated. Enzymatic extracts were prepared from aloe vera gel by using ten digestive enzymes including five carbohydrases and five proteases. Among them, the highest yield was obtained with the Viscozyme extract and the same extract showed the best radical scavenging activity. An active polysaccharide was purified from the Viscozyme extract using ethanol-added separation and anion exchange chromatography. Purified aloe vera polysaccharide (APS) strongly scavenged radicals including DPPH, hydroxyl and alkyl radicals. In addition, APS showed a protective effect against AAPH-induced oxidative stress and cell death in Vero cells as well as in the in vivo zebrafish model. In this study, it is proved that both the in vitro and in vivo antioxidant potentials of APS could be further utilized in relevant industrial applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

Heparin-like entities from marine organisms.

PubMed

Colliec-Jouault, S; Bavington, C; Delbarre-Ladrat, C

2012-01-01

Polysaccharides are ubiquitous in animals and plant cells where they play a significant role in a number of physiological situations e.g. hydration, mechanical properties of cell walls and ionic regulation. This review concentrates on heparin-like entities from marine procaryotes and eukaryotes. Carbohydrates from marine prokaryotes offer a significant structural chemodiversity with novel material and biological properties. Cyanobacteria are Gram-negative photosynthetic prokaryotes considered as a rich source of novel molecules, and marine bacteria are a rich source of polysaccharides with novel structures, which may be a good starting point from which to synthesise heparinoid molecules. For example, some sulphated polysaccharides have been isolated from gamma-proteobacteria such as Alteromonas and Pseudoalteromonas sp. In contrast to marine bacteria, all marine algae contain sulphated wall polysaccharides, whereas such polymers are not found in terrestrial plants. In their native form, or after chemical modifications, a range of polysaccharides isolated from marine organisms have been described that have anticoagulant, anti-thrombotic, anti-tumour, anti-proliferative, anti-viral or anti-inflammatory activities.In spite of the enormous potential of sulphated oligosaccharides from marine sources, their technical and pharmaceutical usage is still limited because of the high complexity of these molecules. Thus, the production of tailor-made oligo- and polysaccharidic structures by biocatalysis is also a growing field of interest in biotechnology.

Synthesis of 3-O-sulfonated heparan sulfate octasaccharides that inhibit the herpes simplex virus type 1 host-cell interaction

NASA Astrophysics Data System (ADS)

Hu, Yu-Peng; Lin, Shu-Yi; Huang, Cheng-Yen; Zulueta, Medel Manuel L.; Liu, Jing-Yuan; Chang, Wen; Hung, Shang-Cheng

2011-07-01

Cell surface carbohydrates play significant roles in a number of biologically important processes. Heparan sulfate, for instance, is a ubiquitously distributed polysulfated polysaccharide that is involved, among other things, in the initial step of herpes simplex virus type 1 (HSV-1) infection. The virus interacts with cell-surface heparan sulfate to facilitate host-cell attachment and entry. 3-O-Sulfonated heparan sulfate has been found to function as an HSV-1 entry receptor. Achieving a complete understanding of these interactions requires the chemical synthesis of such oligosaccharides, but this remains challenging. Here, we present a convenient approach for the synthesis of two irregular 3-O-sulfonated heparan sulfate octasaccharides, making use of a key disaccharide intermediate to acquire different building blocks for the oligosaccharide chain assembly. Despite substantial structural differences, the prepared 3-O-sulfonated sugars blocked viral infection in a dosage-dependent manner with remarkable similarity to one another.

Enzymatic cell wall degradation of Chlorella vulgaris and other microalgae for biofuels production.

PubMed

Gerken, Henri G; Donohoe, Bryon; Knoshaug, Eric P

2013-01-01

Cell walls of microalgae consist of a polysaccharide and glycoprotein matrix providing the cells with a formidable defense against its environment. We characterized enzymes that can digest the cell wall and weaken this defense for the purpose of protoplasting or lipid extraction. A growth inhibition screen demonstrated that chitinase, lysozyme, pectinase, sulfatase, β-glucuronidase, and laminarinase had the broadest effect across the various Chlorella strains tested and also inhibited Nannochloropsis and Nannochloris strains. Chlorella is typically most sensitive to chitinases and lysozymes, both enzymes that degrade polymers containing N-acetylglucosamine. Using a fluorescent DNA stain, we developed rapid methodology to quantify changes in permeability in response to enzyme digestion and found that treatment with lysozyme in conjunction with other enzymes has a drastic effect on cell permeability. Transmission electron microscopy of enzymatically treated Chlorella vulgaris indicates that lysozyme degrades the outer surface of the cell wall and removes hair-like fibers protruding from the surface, which differs from the activity of chitinase. This action on the outer surface of the cell causes visible protuberances on the cell surface and presumably leads to the increased settling rate when cells are treated with lysozyme. We demonstrate radical ultrastructural changes to the cell wall in response to treatment with various enzyme combinations which, in some cases, causes a greater than twofold increase in the thickness of the cell wall. The enzymes characterized in this study should prove useful in the engineering and extraction of oils from microalgae.

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

Higuchi, T.

A textbook containing 22 chapters by various authors covers the structure of wood, the localization of polysaccharides and lignins in wood cell walls, metabolism and synthetic function of cambial tissue, cell organelles and their function in the biosynthesis of cell wall components, biosynthesis of plant cell wall polysaccharides, lignin, cutin, suberin and associated waxes, phenolic acids and monolignols, quinones, flavonoids, tannins, stilbenes and terpenoid wood extractives, the occurrence of extractives, the metabolism of phenolic acids, wood degradation by micro-organisms and fungi, and biodegradation of cellulose, hemicelluloses, lignin, and aromatic extractives of wood. An index is included.

Antimicrobial Action and Cell Agglutination by the Eosinophil Cationic Protein Are Modulated by the Cell Wall Lipopolysaccharide Structure

PubMed Central

Pulido, David; Moussaoui, Mohammed; Andreu, David; Nogués, M. Victòria

2012-01-01

Antimicrobial proteins and peptides (AMPs) are essential effectors of innate immunity, acting as a first line of defense against bacterial infections. Many AMPs exhibit high affinity for cell wall structures such as lipopolysaccharide (LPS), a potent endotoxin able to induce sepsis. Hence, understanding how AMPs can interact with and neutralize LPS endotoxin is of special relevance for human health. Eosinophil cationic protein (ECP) is an eosinophil secreted protein with high activity against both Gram-negative and Gram-positive bacteria. ECP has a remarkable affinity for LPS and a distinctive agglutinating activity. By using a battery of LPS-truncated E. coli mutant strains, we demonstrate that the polysaccharide moiety of LPS is essential for ECP-mediated bacterial agglutination, thereby modulating its antimicrobial action. The mechanism of action of ECP at the bacterial surface is drastically affected by the LPS structure and in particular by its polysaccharide moiety. We have also analyzed an N-terminal fragment that retains the whole protein activity and displays similar cell agglutination behavior. Conversely, a fragment with further minimization of the antimicrobial domain, though retaining the antimicrobial capacity, significantly loses its agglutinating activity, exhibiting a different mechanism of action which is not dependent on the LPS composition. The results highlight the correlation between the protein's antimicrobial activity and its ability to interact with the LPS outer layer and promote bacterial agglutination. PMID:22330910

Antimicrobial action and cell agglutination by the eosinophil cationic protein are modulated by the cell wall lipopolysaccharide structure.

PubMed

Pulido, David; Moussaoui, Mohammed; Andreu, David; Nogués, M Victòria; Torrent, Marc; Boix, Ester

2012-05-01

Antimicrobial proteins and peptides (AMPs) are essential effectors of innate immunity, acting as a first line of defense against bacterial infections. Many AMPs exhibit high affinity for cell wall structures such as lipopolysaccharide (LPS), a potent endotoxin able to induce sepsis. Hence, understanding how AMPs can interact with and neutralize LPS endotoxin is of special relevance for human health. Eosinophil cationic protein (ECP) is an eosinophil secreted protein with high activity against both Gram-negative and Gram-positive bacteria. ECP has a remarkable affinity for LPS and a distinctive agglutinating activity. By using a battery of LPS-truncated E. coli mutant strains, we demonstrate that the polysaccharide moiety of LPS is essential for ECP-mediated bacterial agglutination, thereby modulating its antimicrobial action. The mechanism of action of ECP at the bacterial surface is drastically affected by the LPS structure and in particular by its polysaccharide moiety. We have also analyzed an N-terminal fragment that retains the whole protein activity and displays similar cell agglutination behavior. Conversely, a fragment with further minimization of the antimicrobial domain, though retaining the antimicrobial capacity, significantly loses its agglutinating activity, exhibiting a different mechanism of action which is not dependent on the LPS composition. The results highlight the correlation between the protein's antimicrobial activity and its ability to interact with the LPS outer layer and promote bacterial agglutination.

Hericium erinaceus polysaccharide facilitates restoration of injured intestinal mucosal immunity in Muscovy duck reovirus-infected Muscovy ducklings.

PubMed

Wu, Yijian; Jiang, Huihui; Zhu, Erpeng; Li, Jian; Wang, Quanxi; Zhou, Wuduo; Qin, Tao; Wu, Xiaoping; Wu, Baocheng; Huang, Yifan

2018-02-01

To elucidate the effect of Hericium erinaceus polysaccharide (HEP) on the intestinal mucosal immunity in normal and Muscovy duck reovirus (MDRV)-infected Muscovy ducklings, 1-day-old healthy Muscovy ducklings were pretreated with 0.2g/L HEP and/or following by MDRV infection in this study, duodenal samples were respectively collected at 1, 3, 6, 10, 15 and 21day post-infection, tissue sections were prepared for observation of morphological structure and determination of intestinal parameters (villus height/crypt depth ratio, villus surface area) as well as counts of intraepithelial lymphocytes (IELs), goblet cells, mast cells. Additionally, dynamics of secretory immunoglobin A (sIgA), interferon-γ (IFN-γ) and interleukin-4 (IL-4) productions in intestinal mucosa were measured with radioimmunoassay. Results showed that HEP significantly improved intestinal morphological structure and related indexes, and significantly inhibited the reduction of intestinal mucosal IELs, goblet cells and mast cells caused by MDRV infection. Furthermore, HEP significantly increased the secretion of sIgA, IFN-γ and IL-4 to enhance intestinal mucosal immune functions. Our findings indicate that HEP treatment can effectively repair MDRV-caused injures of small intestinal mucosal immune barrier, and improve mucosal immune function in sick Muscovy ducklings, which will provide valuable help for further application of HEP in prevention and treatment of MDRV infection. Copyright © 2017. Published by Elsevier B.V.

Purification, antitumor and immunomodulatory activity of polysaccharides from soybean residue fermented with Morchella esculenta.

PubMed

Li, Shuhong; Gao, Ang; Dong, Shuang; Chen, Ye; Sun, Shuang; Lei, Zhongfang; Zhang, Zhenya

2017-03-01

Crude polysaccharides (MPS) from soybean residue fermented with Morchella esculenta were extracted and purified by DEAE Sephadex A-50 chromatography and Sephadex G-100 size-exclusion chromatography in sequence. Three main fractions MP-1, MP-3 and MP-4 were obtained during the purification steps. The recovery rates based on MPS used were 26.2%, 29.1% and 18.7% for MP-1, MP-3 and MP-4 respectively. The monosaccharide composition, ultraviolet spectrum, infrared spectrum and NMR of the three fractions were analyzed. Furthermore, the influence of polysaccharides fractions upon activation of macrophage cells (RAW 264.7), antitumor activities of the human hepatocellular cell line (HepG-2) and human cervical carcinoma cells (Hela) in vitro were evaluated. The results indicated that the proliferation of MP-3 on RAW 264.7 was 313.57% at 25μg/mL, which is high while MP-1 had a higher growth inhibition effect on HepG-2 cells of 68.01% at concentration of 50μg/mL. The fractions of MP-1, MP-3 and MP-4 induced apoptosis in HepG-2 cells and Hela cells by arresting cell cycle progression at the G 0 /G 1 phase. These findings suggest that the purified polysaccharides fractions may be a potent candidate for human hepatocellular and cervical carcinoma treatment and prevention in functional foods and pharmacological fields. Copyright © 2016 Elsevier B.V. All rights reserved.

Immune Recognition of Fungal Polysaccharides.

PubMed

Snarr, Brendan D; Qureshi, Salman T; Sheppard, Donald C

2017-08-28

The incidence of fungal infections has dramatically increased in recent years, in large part due to increased use of immunosuppressive medications, as well as aggressive medical and surgical interventions that compromise natural skin and mucosal barriers. There are relatively few currently licensed antifungal drugs, and rising resistance to these agents has led to interest in the development of novel preventative and therapeutic strategies targeting these devastating infections. One approach to combat fungal infections is to augment the host immune response towards these organisms. The polysaccharide-rich cell wall is the initial point of contact between fungi and the host immune system, and therefore, represents an important target for immunotherapeutic approaches. This review highlights the advances made in our understanding of the mechanisms by which the immune system recognizes and interacts with exopolysaccharides produced by four of the most common fungal pathogens: Aspergillus fumigatus , Candida albicans , Cryptococcus neoformans , and Histoplasma capsulatum . Work to date suggests that inner cell wall polysaccharides that play an important structural role are the most conserved across diverse members of the fungal kingdom, and elicit the strongest innate immune responses. The immune system senses these carbohydrates through receptors, such as lectins and complement proteins. In contrast, a greater diversity of polysaccharides is found within the outer cell walls of pathogenic fungi. These glycans play an important role in immune evasion, and can even induce anti-inflammatory host responses. Further study of the complex interactions between the host immune system and the fungal polysaccharides will be necessary to develop more effective therapeutic strategies, as well as to explore the use of immunosuppressive polysaccharides as therapeutic agents to modulate inflammation.

Cell surface physiology and outer cell envelope impermeability for hydrophobic substances in Burkholderia multivorans.

PubMed

Ruskoski, Sallie A; Champlin, Franklin R

2017-07-01

The purpose of the present study was to obtain a better understanding of the relationship between cell surface physiology and outer cellular envelope permeability for hydrophobic substances in mucoid and non-mucoid B. multivorans strains, as well as in two capsule-deficient derivatives of a mucoid parental strain. Cell surface hydrophobicity properties were determined using the hydrocarbon adherence method, while outer cell envelope accessibility and permeability for non-polar compounds were measured using hydrophobic antimicrobial agent susceptibility and fluorescent probe assays. Extracellular polysaccharide (EPS) production was assessed by cultivating strains of disparate origin on yeast extract agar (YEA) containing different sugars, while the resultant colonial and cellular morphological parameters were assessed macro- and microscopically, respectively.Results/Key findings. The cell surfaces of all the strains were hydrophilic, impermeable to mechanistically disparate hydrophobic antibacterial agents and inaccessible to the hydrophobic probe N-phenyl-1-napthylamine, regardless of EPS phenotype. Supplementation of basal YEA with eight different sugars enhanced macroscopic EPS expression for all but one non-mucoid strain, with mannose potentiating the greatest effect. Despite acquisition of the mucoid phenotype, non-mucoid strains remained non-capsulated and capsulation of a hyper-mucoid strain and its two non-mucoid derivative strains was unaffected, as judged by microscopic observation. These data support the conclusion that EPS expression and the consistent mucoid phenotype are not necessarily associated with the ability of the outer cell surface to associate with non-polar substances or cellular capsulation.

Cytotoxicity of blended versus single medicinal mushroom extracts on human cancer cell lines: contribution of polyphenol and polysaccharide content.

PubMed

Durgo, Ksenija; Koncar, Mladen; Komes, Drazenka; Belscak-Cvitanovic, Ana; Franekic, Jasna; Jakopovich, Ivan; Jakopovich, Neven; Jakopovich, Boris

2013-01-01

The use of mushrooms contributes to human nutrition by providing low lipid content of lipids and high dietary fiber content, as well as significant content of other biologically active compounds such as polysaccharides, minerals, vitamins, and polyphenolic antioxidants. This study aimed to determine the content of polyphenols and polysaccharides, as well as the cytotoxic and antioxidative properties of several medicinal mushroom preparations. The content of total phenols and flavonoids of preparations of blended mushroom extracts (Lentifom, Super Polyporin, Agarikon, Agarikon Plus, Agarikon.1, and Mykoprotect.1) was evaluated quantitatively by using ultraviolet-visible spectroscopy spectrophotometric methods. The antioxidant capacity of the preparations was evaluated using the ABTS (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) and ferric reducing/antioxidant power assays. The content of water-soluble polysaccharides was determined using a specific gravimetric method, based on ethanol precipitation. To determine cytotoxic effects of single and blended mushroom extracts, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and neutral red assays were conducted using human small cell lung cancer, lung adenocarcinoma, colon cancer, and brain astrocytoma cancer cells. The obtained results suggest that due to the significant content of beneficial polyphenolic antioxidants and soluble polysaccharides, use of these mushroom preparations is beneficial in maintaining good health, as well as in the prevention and adjuvant biotherapy of various human pathological aberrations. These results reveal that these extracts exhibit different cytotoxic effects on tumor cells originating from different tissues. In addition, the comparison of investigated blended mushroom extracts with three well-known commercial mushroom products derived from single mushroom species or single mushroom compounds shows that blended mushroom extracts exhibit significantly stronger cytotoxic effects on human tumor cell lines.

Multienzyme decorated polysaccharide amplified electrogenerated chemiluminescence biosensor for cytosensing and cell surface carbohydrate profiling.

PubMed

Zhang, Ling; Wang, Yangzhong; Tian, Qianqian; Liu, Yang; Li, Jinghong

2017-03-15

A novel ECL biosensor for cytosensing and cell surface carbohydrate expression evaluation was developed, by the integration of the peptide modified interface for highly specific carbohydrate recognition and sodium alginate loaded glucose oxidase as the signal probe with high signal amplification efficiency. A cysteine-terminated peptide self-assembled on the electrode through Au-S bond to construct a functional interface for cell capture, with decent biocompatibility and high affinity for the human breast cancer cell MCF-7. Concanavalin A lectin modified gold nanoparticles specifically recognized the cell surface carbohydrates and were absorbed on the electrode, followed by the immobilization of multiple glucose oxidase conjugated sodium alginate, which could remarkably increase the sensitivity of the biosensor with enhanced catalysis. The as-proposed ECL cytosensor was successfully applied for the detection of the MCF-7 tumor cells, whose glycans on the cell membranes are over-expressed. A low detection limit of 150cellsmL -1 was obtained, with a wide dynamic linear range from 5.0×10 2 to 5.0×10 5 cellsmL -1 . Due to the excellent sensitivity, stability and biocompatibility, the ECL biosensor would be promising in reliable diagnostics of glycan relevant biomarkers for cancer and other diseases. Copyright © 2016 Elsevier B.V. All rights reserved.

Impact of RGD amount in dextran-based hydrogels for cell delivery.

PubMed

Riahi, Nesrine; Liberelle, Benoît; Henry, Olivier; De Crescenzo, Gregory

2017-04-01

Dextran is one of the hydrophilic polymers that is used for hydrogel preparation. As any polysaccharide, it presents a high density of hydroxyl groups, which make possible several types of derivatization and crosslinking reactions. Furthermore, dextran is an excellent candidate for hydrogel fabrication with controlled cell/scaffold interactions as it is resistant to protein adsorption and cell adhesion. RGD peptide can be grafted to the dextran in order to promote selected cell adhesion and proliferation. Altogether, we have developed a novel strategy to graft the RGD peptide sequence to dextran-based hydrogel using divinyl sulfone as a linker. The resulting RGD functionalized dextran-based hydrogels were transparent, presented a smooth surface and were easy to handle. The impact of varying RGD peptide amounts, hydrogel porosity and topology upon human umbilical vein endothelial cell (HUVEC) adhesion, proliferation and infiltration was investigated. Our results demonstrated that 0.1% of RGD-modified dextran within the gel was sufficient to support HUVEC cells adhesion to the hydrogel surface. Sodium chloride was added (i) to the original hydrogel mix in order to form a macroporous structure presenting interconnected pores and (ii) to the hydrogel surface to create small orifices essential for cells migration inside the matrix. Copyright © 2017 Elsevier Ltd. All rights reserved.

Role of molecular properties of ulvans on their ability to elaborate antiadhesive surfaces.

PubMed

Gadenne, Virginie; Lebrun, Laurent; Jouenne, Thierry; Thebault, Pascal

2015-03-01

Antiadhesive properties of polysaccharides (such ulvans) once immobilized on a surface are described in the literature but the parameters governing their antifouling properties are not yet well identified. In the present study, the relationship between molecular parameters of ulvans and the inhibition of bacterial adhesion was investigated. To this aim, various ulvans were grafted on silicon wafers under two different experimental immobilization conditions. Results showed that the experimental immobilization conditions and the polysaccharides molecular weight led to specific layer conformations which exhibited a key role in the surface antiadhesive properties. © 2014 Wiley Periodicals, Inc.

Maca polysaccharides: Extraction optimization, structural features and anti-fatigue activities.

PubMed

Li, Yujuan; Xin, Yizhou; Xu, Fangxue; Zheng, Mengmeng; Xi, Xiaozhi; Cui, Xiaowei; Cao, Hui; Guo, Hong; Han, Chunchao

2018-08-01

The maca polysaccharides optimal extraction conditions were obtained by using response surface methodology (RSM) method and the anti-fatigue activity of maca polysaccharides (MCP) was explored. The maca polysaccharides extract yield of RSM could reach 9.97 mg/g by using the model predicts, and the total sugar and protein purity were 61.00% and 4.46% with the further isolation process, respectively. And the monosaccharide compositions obtained by gas chromatograph (GC) were composed of rhamnose (rha), glucose (glc), galactose (gal) with the ratio of 2.34:10.21:1.00. Furthermore, the anti-fatigue activity was evaluated by the swimming parameter, biochemistry parameters (liver glycogen (LG), blood urea nitrogen (BUN), and lactic acid (LD)), the result indicated that the low-dose maca polysaccharides group had the significant anti-fatigue activity. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

Antiviral Potential of Algae Polysaccharides Isolated from Marine Sources: A Review.

PubMed

Ahmadi, Azin; Zorofchian Moghadamtousi, Soheil; Abubakar, Sazaly; Zandi, Keivan

2015-01-01

From food to fertilizer, algal derived products are largely employed in assorted industries, including agricultural, biomedical, food, and pharmaceutical industries. Among different chemical compositions isolated from algae, polysaccharides are the most well-established compounds, which were subjected to a variety of studies due to extensive bioactivities. Over the past few decades, the promising results for antiviral potential of algae-derived polysaccharides have advocated them as inordinate candidates for pharmaceutical research. Numerous studies have isolated various algal polysaccharides possessing antiviral activities, including carrageenan, alginate, fucan, laminaran, and naviculan. In addition, different mechanisms of action have been reported for these polysaccharides, such as inhibiting the binding or internalization of virus into the host cells or suppressing DNA replication and protein synthesis. This review strives for compiling previous antiviral studies of algae-derived polysaccharides and their mechanism of action towards their development as natural antiviral agents for future investigations.

Cellulose Surface Degradation by a Lytic Polysaccharide Monooxygenase and Its Effect on Cellulase Hydrolytic Efficiency*

PubMed Central

Eibinger, Manuel; Ganner, Thomas; Bubner, Patricia; Rošker, Stephanie; Kracher, Daniel; Haltrich, Dietmar; Ludwig, Roland; Plank, Harald; Nidetzky, Bernd

2014-01-01

Lytic polysaccharide monooxygenase (LPMO) represents a unique principle of oxidative degradation of recalcitrant insoluble polysaccharides. Used in combination with hydrolytic enzymes, LPMO appears to constitute a significant factor of the efficiency of enzymatic biomass depolymerization. LPMO activity on different cellulose substrates has been shown from the slow release of oxidized oligosaccharides into solution, but an immediate and direct demonstration of the enzyme action on the cellulose surface is lacking. Specificity of LPMO for degrading ordered crystalline and unordered amorphous cellulose material of the substrate surface is also unknown. We show by fluorescence dye adsorption analyzed with confocal laser scanning microscopy that a LPMO (from Neurospora crassa) introduces carboxyl groups primarily in surface-exposed crystalline areas of the cellulosic substrate. Using time-resolved in situ atomic force microscopy we further demonstrate that cellulose nano-fibrils exposed on the surface are degraded into shorter and thinner insoluble fragments. Also using atomic force microscopy, we show that prior action of LPMO enables cellulases to attack otherwise highly resistant crystalline substrate areas and that it promotes an overall faster and more complete surface degradation. Overall, this study reveals key characteristics of LPMO action on the cellulose surface and suggests the effects of substrate morphology on the synergy between LPMO and hydrolytic enzymes in cellulose depolymerization. PMID:25361767

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.

The Cell Wall of the Human Fungal Pathogen Aspergillus fumigatus: Biosynthesis, Organization, Immune Response, and Virulence.

PubMed

Latgé, Jean-Paul; Beauvais, Anne; Chamilos, Georgios

2017-09-08

More than 90% of the cell wall of the filamentous fungus Aspergillus fumigatus comprises polysaccharides. Biosynthesis of the cell wall polysaccharides is under the control of three types of enzymes: transmembrane synthases, which are anchored to the plasma membrane and use nucleotide sugars as substrates, and cell wall-associated transglycosidases and glycosyl hydrolases, which are responsible for remodeling the de novo synthesized polysaccharides and establishing the three-dimensional structure of the cell wall. For years, the cell wall was considered an inert exoskeleton of the fungal cell. The cell wall is now recognized as a living organelle, since the composition and cellular localization of the different constitutive cell wall components (especially of the outer layers) vary when the fungus senses changes in the external environment. The cell wall plays a major role during infection. The recognition of the fungal cell wall by the host is essential in the initiation of the immune response. The interactions between the different pattern-recognition receptors (PRRs) and cell wall pathogen-associated molecular patterns (PAMPs) orientate the host response toward either fungal death or growth, which would then lead to disease development. Understanding the molecular determinants of the interplay between the cell wall and host immunity is fundamental to combatting Aspergillus diseases.

Antitumor and immunomodulating activity of a polysaccharide from Sophora flavescens Ait.

PubMed

Bai, Lu; Zhu, Li-Ying; Yang, Bao-Shan; Shi, Li-Jun; Liu, Yong; Jiang, Ai-Min; Zhao, Li-Li; Song, Guang; Liu, Tie-Fu

2012-12-01

The immunostimulatory activity of Sophora flavescens polysaccharide (SFPW1) was evaluated by using in vitro cell models and in vivo animal models. The results demonstrated that SFPW1 could effectively inhibit the tumor growth in H22 tumor-bearing mice and promote the splenocyte proliferation, thus resulting in a prolonged life survival. For assay in vitro, SFPW1 significantly strengthened peritoneal macrophages to devour H22 tumor cells and stimulated macrophages to produce nitric oxide (NO) via up-regulation of inducible NO synthase (iNOS) activity. However, no direct cytotoxicity against H22 tumor cells was observed in vitro. These results suggest that SFPW1 might be a strong natural immunomodulator and the antitumor effect of this polysaccharide is associated with its potent immunostimulating effect. Copyright © 2012 Elsevier B.V. All rights reserved.

Multiple Effects of Ginseng Berry Polysaccharides: Plasma Cholesterol Level Reduction and Enteric Neoplasm Prevention.

PubMed

Wan, Jin-Yi; Huang, Wei-Hua; Zheng, Wei; Park, Chan Woong; Kim, Su Hwan; Seo, Dae Bang; Shin, Kwang-Soon; Zeng, Jinxiang; Yao, Haiqiang; Sava-Segal, Clara; Wang, Chong-Zhi; Yuan, Chun-Su

2017-01-01

The root of Asian ginseng (Panax ginseng C.A. Meyer) has been used for centuries in Oriental medicine to improve general well-being and to relieve various medical conditions. It is commonly understood that ginsenosides are responsible for the pharmacological activities of ginseng. Compared to the root of ginseng, studies on the berry are considerably limited. In this study, we evaluated the effects of polysaccharides from Asian ginseng berries on plasma lipid levels, chemically-induced enteric inflammation and neoplasm, and cancer chemoprevention in different experimental models. We tested two polysaccharide preparations: regular ginseng berry polysaccharide extract (GBPE) and ginseng berry polysaccharide portion (GBPP, removed MV [Formula: see text]). We first observed that both oral GBPE and oral GBPP significantly reduced plasma cholesterol and triglycerides levels in a dose-related manner in ob/ob mice, without obvious body weight changes. Then, in AOM/DSS-induced acute colitis mice, GBPE and GBPP significantly ameliorated the increased gut disease activity index and inhibited the reduction of the colon length. Further, the berry polysaccharides significantly suppressed chemically-induced pro-inflammatory cytokine levels. This is consistent with the observation that GBPE and GBPP attenuated tumorigenesis in mice by significantly and dose-dependently reducing tumor load. Finally, in vitro HCT-116 and HT-29 human colon cancer cells were used. While these berry preparations had better antiproliferation effects on the HCT-116 than the HT-29 cells, the GBPE had significantly stronger inhibitory effects than GBPP. The observed in vitro GBPE's effect could contribute to the actions of its small-molecule non-polysaccharide compounds due to their direct antiproliferative activities. Results obtained from the present study suggest that ginseng berry polysaccharides may have a therapeutic role in the management of high lipid levels, enteric inflammation, and colon malignancies.

The Anti-Oxidant and Antitumor Properties of Plant Polysaccharides.

PubMed

Jiao, Rui; Liu, Yingxia; Gao, Hao; Xiao, Jia; So, Kwok Fai

2016-01-01

Oxidative stress has been increasingly recognized as a major contributing factor in a variety of human diseases, from inflammation to cancer. Although certain parts of signaling pathways are still under investigation, detailed molecular mechanisms for the induction of diseases have been elucidated, especially the link between excessive oxygen reactive species (ROS) damage and tumorigenesis. Emerging evidence suggests anti-oxidant therapy can play a key role in treating those diseases. Among potential drug resources, plant polysaccharides are natural anti-oxidant constituents important for human health because of their long history in ethnopharmacology, wide availability and few side effects upon consumption. Plant polysaccharides have been shown to possess anti-oxidant, anti-inflammation, cell viability promotion, immune-regulation and antitumor functions in a number of disease models, both in laboratory studies and in the clinic. In this paper, we reviewed the research progress of signaling pathways involved in the initiation and progression of oxidative stress- and cancer-related diseases in humans. The natural sources, structural properties and biological actions of several common plant polysaccharides, including Lycium barbarum, Ginseng, Zizyphus Jujuba, Astragalus lentiginosus, and Ginkgo biloba are discussed in detail, with emphasis on their signaling pathways. All of the mentioned common plant polysaccharides have great potential to treat oxidative stress and cancinogenic disorders in cell models, animal disease models and clinical cases. ROS-centered pathways (e.g. mitochondrial autophagy, MAPK and JNK) and transcription factor-related pathways (e.g. NF-[Formula: see text]B and HIF) are frequently utilized by these polysaccharides with or without the further involvement of inflammatory and death receptor pathways. Some of the polysaccharides may also influence tumorigenic pathways, such as Wnt and p53 to play their anti-tumor roles. In addition, current problems and future directions for the application of those plant polysaccharides are also listed and discussed.

Surface Characterization of Populus during Caldicellulosiruptor bescii Growth by TOF-SIMS Analysis

DOE PAGES

Tolbert, Allison K.; Young, Jenna M.; Jung, Seokwon; ...

2017-01-30

Caldicellulosiruptor bescii is a thermophilic, anaerobic bacterium that is capable of utilizing unpretreated biomass in addition to breaking down cellulose and hemicellulose into simple sugars. Despite the fact that C. bescii must first bind to the surface of the biomass, there has been no analysis of the morphological or chemical changes to the biomass surface as a result of incubation with the micro-organism. To understand more about C. bescii growth, juvenile poplar stems were sectioned (80 μm thick) and incubated with C. bescii beyond the typical 24 h experiment length. Monitoring the cell counts during incubation revealed a biphasic growthmore » pattern. The impact the micro-organism had on the surface was determined by scanning electron microscopy (SEM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS), which showed physical crevices in the cell wall caused by the C. bescii along with a decrease of polysaccharide ions and an increase in lignin ions on the poplar surface. Employing infrared microspectroscopy, the decreasing trend was corroborated.« less

A polysaccharide from the fruiting bodies of Agaricus blazei Murill induces caspase-dependent apoptosis in human leukemia HL-60 cells.

PubMed

Li, Xiaohui; Zhao, Xin; Wang, Hongmin; Han, Junqing; Liu, Li

2014-09-01

Polysaccharides are the major active ingredients of fungus Agaricus blazei for treating and preventing cancer. However, there are no reports showing anti-tumor activity of A. blazei polysaccharides (ABP) on human leukemia (HL)-60 cells in vitro and in vivo. In this study, we demonstrated that ABP efficiently inhibited proliferation of cultured HL-60 cells, which was associated with the induction of apoptosis. The increase in ABP-induced apoptosis was accompanied by loss of mitochondria membrane potential (∆Ψm), cytochrome c release from the mitochondria, activation of caspase-3, degradation of poly(ADP-ribose) polymerase (PARP), and the elevated ratio of Bcl-2-associated X (Bax)/B-cell lymphoma 2 (Bcl-2). Moreover, z-DEVD-fmk, a caspase-3 inhibitor, reversed the cytotoxic effects and apoptotic characteristics induced by ABP in HL-60 cells. Furthermore, we confirmed that ABP could obviously inhibit the solid cancer growth of leukemia HL-60 in tumor xenograft model. These data demonstrated that ABP effectively induced the apoptosis of HL-60 cells via a signaling cascade of mitochondrial caspase-3-dependent pathway.

Effect of different drying methods on chemical composition and bioactivity of tea polysaccharides.

PubMed

Wang, Yuanfeng; Liu, Yangyang; Huo, Jianglei; Zhaoa, Xintong; Zhao, Tingtong; Zheng, Jian; Ren, Jian; Wei, Xinlin

2013-11-01

Four polysaccharides (TPS-F, TPS-V, TPS-S and TPS-M) were obtained from tea (Camellia sinensis) leaves by freeze-drying, vacuum-drying, spray-drying and microwave-vacuum drying, respectively. Their chemical composition and biological properties were comparatively studied. The results showed these TPS were similar in IR, UV absorption and distribution of molecular weight. However, they showed significant differences (P<0.05) in yields of crude polysaccharides and contents of protein and total polyphenols. Furthermore, morphological analysis showed their surface differed from each other in size and shape when viewed by SEM, from which surface of TPS-F was rough and porous, surface of TPS-S was evenly particles, and surfaces of the other two were similar to anomalistic bricks. In addition, the bioactivity of them was also evaluated. It was found TPS-F exhibited relatively better ability on metal chelating and superoxide radicals scavenging assays than others, and TPS-V exhibited higher ability on α-glycosidase and α-amylase inhibition assays than others with inhibitory percentages of 82.75% and 92.8%. Copyright © 2013 Elsevier B.V. All rights reserved.

Polysialic acid immobilized on silanized glass surfaces: a test case for its use as a biomaterial for nerve regeneration.

PubMed

Steinhaus, Stephanie; Stark, Yvonne; Bruns, Stephanie; Haile, Yohannes; Scheper, Thomas; Grothe, Claudia; Behrens, Peter

2010-04-01

The immobilization of polysialic acid (polySia) on glass substrates has been investigated with regard to the applicability of this polysaccharide as a novel, biocompatible and bioresorbable material for tissue engineering, especially with regard to its use in nerve regeneration. PolySia, a homopolymer of alpha-2,8-linked sialic acid, is involved in post-translational modification of the neural cell adhesion molecule (NCAM). The degradation of polySia can be controlled which makes it an interesting material for coating and for scaffold construction in tissue engineering. Here, we describe the immobilization of polySia on glass surfaces via an epoxysilane linker. Whereas glass surfaces will not actually be used in nerve regeneration scaffolds, they provide a simple and efficient means for testing various methods for the investigation of immobilized polySia. The modified surfaces were investigated with contact angle measurements and the quantity of immobilized polySia was examined by the thiobarbituric acid assay and a specific polySia-ELISA. The interactions between the polySia-modified surface and immortalized Schwann cells were evaluated via cell adhesion and cell viability assays. The results show that polySia can be immobilized on glass surfaces via the epoxysilane linker and that surface-bound polySia has no toxic effects on Schwann cells. Therefore, as a key substance in the development of vertebrates and as a favourable substrate for the cultivation of Schwann cells, it offers interesting features for the use in nerve guidance tubes for treatment of peripheral nerve injuries.

Layer-by-layer assembled cell instructive nanocoatings containing platelet lysate.

PubMed

Oliveira, Sara M; Santo, Vítor E; Gomes, Manuela E; Reis, Rui L; Mano, João F

2015-04-01

Great efforts have been made to introduce growth factors (GFs) onto 2D/3D constructs in order to control cell behavior. Platelet lysate (PL) presents itself as a cost-effective source of multiple GFs and other proteins. The instruction given by a construct-PL combination will depend on how its instructive cues are presented to the cells. The content, stability and conformation of the GFs affect their instruction. Strategies for a controlled incorporation of PL are needed. Herein, PL was incorporated into nanocoatings by layer-by-layer assembling with polysaccharides presenting different sulfation degrees (SD) and charges. Heparin and several marine polysaccharides were tested to evaluate their PL and GF incorporation capability. The consequent effects of those multilayers on human adipose derived stem cells (hASCs) were assessed in short-term cultures. Both nature of the polysaccharide and SD were important properties that influenced the adsorption of PL, vascular endothelial growth factor (VEGF), fibroblast growth factor b (FGFb) and platelet derived growth factor (PDGF). The sulfated polysaccharides-PL multilayers showed to be efficient in the promotion of morphological changes, serum-free adhesion and proliferation of high passage hASCs (P > 5). These biomimetic multilayers promise to be versatile platforms to fabricate instructive devices allowing a tunable incorporation of PL. Copyright © 2015 Elsevier Ltd. All rights reserved.

Analyzing Xyloglucan Endotransglycosylases by Incorporating Synthetic Oligosaccharides into Plant Cell Walls.

PubMed

Ruprecht, Colin; Dallabernardina, Pietro; Smith, Peter J; Urbanowicz, Breeanna R; Pfrengle, Fabian

2018-04-16

The plant cell wall is a cellular exoskeleton consisting predominantly of a complex polysaccharide network that defines the shape of cells. During growth, this network can be loosened through the action of xyloglucan endotransglycosylases (XETs), glycoside hydrolases that "cut and paste" xyloglucan polysaccharides through a transglycosylation process. We have analyzed cohorts of XETs in different plant species to evaluate the substrate specificities of xyloglucan acceptors by using a set of synthetic oligosaccharides obtained by automated glycan assembly. The ability of XETs to incorporate the oligosaccharides into polysaccharides printed as microarrays and into stem sections of Arabidopsis thaliana, beans, and peas was assessed. We found that single xylose substitutions are sufficient for transfer, and xylosylation of the terminal glucose residue is not required by XETs, independent of plant species. To obtain information on the potential xylosylation pattern of the natural acceptor of XETs, that is, the nonreducing end of xyloglucan, we further tested the activity of xyloglucan xylosyl transferase (XXT) 2 on the synthetic xyloglucan oligosaccharides. These data shed light on inconsistencies between previous studies towards determining the acceptor substrate specificities of XETs and have important implications for further understanding plant cell wall polysaccharide synthesis and remodeling. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of sustained release antipsychotic tablets using novel polysaccharide isolated from Delonix regia seeds and its pharmacokinetic studies

PubMed Central

Krishnaraj, Kaliaperumal; Chandrasekar, Mulla Joghi Nanjan; Nanjan, Mulla Joghi; Muralidharan, Selvadurai; Manikandan, Duraikannu

2011-01-01

A natural polysaccharide was isolated from the seeds of Delonix regia. The isolated polysaccharide could maintain aqueous equilibrium between the dosage form and the surrounding medium due to its massive competence of water absorption (80.72%) and swelling index (266.7%). The Scanning Electron Micrograph of a polysaccharide exhibits rough surface with pores and crevices, hence, the drug release will be retarded because of the drug particles entrapment in the pores and crevices. Further, the surface tension of polysaccharide is higher than that of water, which may facilitate sustained release of drugs from dosage forms. An antipsychotic drug, quetiapine fumarate has a short half-life of 6 h and administered multiple times per day. Hence the quetiapine fumarate oral sustained release tablets were formulated using this polysaccharide in the concentration of 5–30% to avoid the side effects and increase patient compliance. Dissolution of the developed tablets with 25% polysaccharide content showed a better release profile than the other batches (5–20%) at the end of 12 h. The strong matrix complex has low solubility in water, it does not dissolve rapidly and the drug continues to diffuse through the gel layer at a consistent rate. Drug release from the matrix tablets follows matrix type except F-4 and F-5 which follow first order and Hix.crow type. The bioavailability study was carried out using healthy male New Zealand white rabbits that show the AUC(0–inf) value for developed SR tablets is 1.44 times higher than the reference thus, indicating more efficient and sustained drug delivery capable of maintaining plasma drug levels better. PMID:24115903

Cellulase-assisted extraction of polysaccharides from Malva sylvestris: Process optimization and potential functionalities.

PubMed

Rostami, Hosein; Gharibzahedi, Seyed Mohammad Taghi

2017-08-01

Enzyme-assisted extraction process of the water-soluble Malva sylvestris polysaccharides (MSPs) was optimized using response surface methodology (RSM). The highest yield (10.40%) of MSPs was achieved at 5.64% cellulase, 55.65°C temperature, 3.4h time, and 5.22 pH. Three homogeneous polysaccharide fractions (MSP-1, MSP-2, MSP-3) were purified by DEAE-cellulose and Sephadex G-100 chromatography, which were composed of galactose, glucuronic acid, arabinose, rhamnose and mannose in different molar ratios with molecular weight range of 2.6×10 5 -8.8×10 5 Da. The fractions could significantly increase antioxidant, antitumor and antimicrobial activities in a dose-dependent pattern. MSP-2 revealed stronger antioxidant activities than MSP-1 and MSP-3, including reducing power and scavenging activity of DPPH and OH radicals. The antiproliferative activity of MSP-2 (1.0mg/mL) on the growth of A549 and HepG2 cells was 45.1% and 53.2%, respectively. The Gram-positive bacteria (Bacillus cereus PTCC 1015 and Staphylococcus aureus PTCC 1112) compared with Gram-negative ones (Escherichia coli PTCC 1763 and Salmonella typhimurium PTCC 1709) showed less sensitivity against the various MSPs (3-15mg/mL). Copyright © 2017 Elsevier B.V. All rights reserved.

Antioxidant activity and optimization of extraction of polysaccharide from the roots of Dipsacus asperoides.

PubMed

Tan, Li-Hong; Zhang, Dan; Yu, Bao; Zhao, Sheng-Ping; Wang, Jian-Wei; Yao, Ling; Cao, Wei-Guo

2015-11-01

Polysaccharide extraction from Dipsacus asperoides roots (DAP) was proved to possess strong antioxidant activities, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-Azobis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical scavenging activities, inhibiting β-carotene bleaching and strong reducing power. Cell assay demonstrated that the crude DAP possessed antioxidant activity and were effective against H2O2-induced L02 cells injury. Then, response surface methodology (RSM) was applied to optimize the ultrasonic extraction of DAP. The optimum variables given by central composite design (CCD) were as follows: ratio of water to raw material, 38.61mL/g; ultrasonic power, 308.68W; extraction time, 38.61min; and extraction temperature, 89°C. Under these conditions, the maximum yield of DAP obtained was 7.12±0.45%. Moreover, high performance liquid chromatography (HPLC) analysis suggested that the monosaccharide compositions of DAP contained primarily mannose, ribose, glucose, galactose, xylose and arabinose, with a molar ratio of 0.22:0.48:2.29:0.34:1.39:1.41. The results of the present study showed that DAP could be considered as potential sources of natural antioxidants. Copyright © 2015 Elsevier B.V. All rights reserved.

Peripheral blood monocyte and T cell subsets in children with specific polysaccharide antibody deficiency (SPAD).

PubMed

Otero, C; Díaz, D; Uriarte, I; Bezrodnik, L; Finiasz, M R; Fink, S

2016-01-01

Specific polysaccharide antibody deficiency (SPAD) is a well reported immunodeficiency characterized by a failure to produce antibodies against polyvalent polysaccharide antigens, expressed by encapsulated microorganisms. The clinical presentation of these patients involves recurrent bacterial infections, being the most frequent agent Streptococcus (S.) pneumoniae. In SPAD patients few reports refer to cells other than B cells. Since the immune response to S. pneumoniae and other encapsulated bacteria was historically considered restricted to B cells, the antibody deficiency seemed enough to justify the repetitive infections in SPAD patients. Our purpose is to determine if the B cell defects reported in SPAD patients are accompanied by defects in other leukocyte subpopulations necessary for the development of a proper adaptive immune response against S. pneumoniae. We here report that age related changes observed in healthy children involving increased percentages of classical monocytes (CD14++ CD16- cells) and decreased intermediate monocytes (CD14++ CD16+ cells), are absent in SPAD patients. Alterations can also be observed in T cells, supporting that the immune deficiency in SPAD patients is more complex than what has been described up to now. Copyright © 2015 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Cell wall polysaccharides released during the alcoholic fermentation by Schizosaccharomyces pombe and S. japonicus: quantification and characterization.

PubMed

Domizio, P; Liu, Y; Bisson, L F; Barile, D

2017-02-01

The present work demonstrates that yeasts belonging to the Schizosaccharomyces genus release a high quantity of polysaccharides of cell wall origin starting from the onset of the alcoholic fermentation. By the end of the alcoholic fermentation, all of the Schizosaccharomyces yeast strains released a quantity of polysaccharides approximately 3-7 times higher than that released by a commercial Saccharomyces cerevisiae yeast strain under the same fermentative conditions of synthetic juice. A higher content of polysaccharide was found in media fermented by Schizosaccharomyces japonicus with respect to that of Schizosaccharomyces pombe. Some of the strains evaluated were also able to produce high levels of pyruvic acid, which has been shown to be an important compound for color stability of wine. The presence of strains with different malic acid consumption patterns along with high polysaccharide release would enable production of naturally modified wines with enhanced mouth feel and reduced acidity. The chemical analysis of the released polysaccharides demonstrated divergence between the two yeast species S. pombe and S. japonicus. A different mannose/galactose ratio and a different percentage of proteins was observed on the polysaccharides released by S. pombe as compared to S. japonicus. Analysis of the proteins released in the media revealed the presence of a glycoprotein with a molecular size around 32-33 kDa only for the species S. japonicus. Mass spectrometry analysis of carbohydrate moieties showed similar proportions among the N-glycan chains released in the media by both yeast species but differences between the two species were also observed. These observations suggest a possible role of rapid MALDI-TOF screening of N-glycans compositional fingerprint as a taxonomic tool for this genus. Polysaccharides release in the media, in particular galactomannoproteins in significant amounts, could make these yeasts particularly interesting also for the industrial production of exogenous polysaccharide preparations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cell wall polysaccharides released during the alcoholic fermentation by Schizosaccharomyces pombe and S. japonicus: quantification and characterization

PubMed Central

Domizio, P.; Liu, Y.; Bisson, L.F.; Barile, D.

2016-01-01

The present work demonstrates that yeasts belonging to the Schizosaccharomyces genus release a high quantity of polysaccharides of cell wall origin starting from the onset of the alcoholic fermentation. By the end of the alcoholic fermentation, all of the Schizosaccharomyces yeast strains released a quantity of polysaccharides approximately 3-7 times higher than that released by a commercial Saccharomyces cerevisiae yeast strain under the same fermentative conditions of synthetic juice. A higher content of polysaccharide was found in media fermented by Schizosaccharomyces japonicus with respect to that of Schizosaccharomyces pombe. Some of the strains evaluated were also able to produce high levels of pyruvic acid, which has been shown to be an important compound for color stability of wine. The presence of strains with different malic acid consumption patterns along with high polysaccharide release would enable production of naturally modified wines with enhanced mouth feel and reduced acidity. The chemical analysis of the released polysaccharides demonstrated divergence between the two yeast species S. pombe and S. japonicus. A different mannose/galactose ratio and a different percentage of proteins was observed on the polysaccharides released by S. pombe as compared to S. japonicus. Analysis of the proteins released in the media revealed the presence of a glycoprotein with a molecular size around 32-33 kDa only for the species S. japonicus. Mass spectrometry analysis of carbohydrate moieties showed similar proportions among the N-glycan chains released in the media by both yeast species but differences between the two species were also observed. These observations suggest a possible role of rapid MALDI-TOF screening of N-glycans compositional fingerprint as a taxonomic tool for this genus. Polysaccharides release in the media, in particular galactomannoproteins in significant amounts, could make these yeasts particularly interesting also for the industrial production of exogenous polysaccharide preparations. PMID:27697163

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

[Astragalus polysaccharide may increase sensitivity of cervical cancer HeLa cells to cisplatin by regulating cell autophagy].

PubMed

Zhai, Qiu-Li; Hu, Xiang-Dan; Xiao, Jing; Yu, Dong-Qing

2018-02-01

This study aimed to investigate the possible sensitivity of Astragalus polysaccharides, in order to improve the chemosensitivity of cervical cancer HeLa cells to cisplatin by regulating the cell autophagy, and explore its possible mechanism. In this study, HeLa cells were divided into control group, cisplatin group, Astragalus polysaccharide group, and Astragalus polysaccharide combined with cisplatin group. MTT assay was used to detect the proliferation of cervical cancer HeLa cells. Flow cytometry was used to detect the apoptosis and cycle of HeLa cells in each experimental group. RT-PCR was used to detect the mRNA expression of autophagy-related proteins beclin1, LC3Ⅱ and p62. The expression levels of autophagy-related proteins beclin1, LC3Ⅱ, LC3Ⅰ and p62 were detected by WB method. MTT results showed that compared with the control group, the proliferation of HeLa cells was significantly inhibited in each administration group( P <0.05), and the inhibitory effect of the combination group was more significant( P <0.01). The apoptotic rate of HeLa cells was significantly increased( P <0.05), and the apoptotic rate of the combination group was significantly increased( P <0.01) compared with the control group( P <0.05).In conclusion, G₀/G₁ phase showed the most significant differences between the two groups. RT-PCR and WB results showed that the gene and protein expressions of beclin1 and LC3Ⅱ were up-regulated, while the gene and protein expressions of p62 were down-regulated compared with the control group. The above-mentioned changes in the combination group were more significant. Through the analysis of the above experimental results, it is speculated that Astragalus polysaccharides may increase the sensitivity of cervical cancer HeLa cells to cisplatin by regulating the cell autophagy. Its possible mechanism of action is correlated with the up-regulation of autophagy-related proteins beclin1, the promote the conversion from LC3Ⅰ to LC3Ⅱ, the down-regulation of labeled protein p62, and the enhancement of HeLa cell autophagic activity, thereby increasing the sensitivity of HeLa cells to cisplatin chemotherapy. Copyright© by the Chinese Pharmaceutical Association.

Recognition and Degradation of Plant Cell Wall Polysaccharides by Two Human Gut Symbionts

PubMed Central

Chiang, Herbert; Pudlo, Nicholas A.; Wu, Meng; McNulty, Nathan P.; Abbott, D. Wade; Henrissat, Bernard; Gilbert, Harry J.; Bolam, David N.; Gordon, Jeffrey I.

2011-01-01

Symbiotic bacteria inhabiting the human gut have evolved under intense pressure to utilize complex carbohydrates, primarily plant cell wall glycans in our diets. These polysaccharides are not digested by human enzymes, but are processed to absorbable short chain fatty acids by gut bacteria. The Bacteroidetes, one of two dominant bacterial phyla in the adult gut, possess broad glycan-degrading abilities. These species use a series of membrane protein complexes, termed Sus-like systems, for catabolism of many complex carbohydrates. However, the role of these systems in degrading the chemically diverse repertoire of plant cell wall glycans remains unknown. Here we show that two closely related human gut Bacteroides, B. thetaiotaomicron and B. ovatus, are capable of utilizing nearly all of the major plant and host glycans, including rhamnogalacturonan II, a highly complex polymer thought to be recalcitrant to microbial degradation. Transcriptional profiling and gene inactivation experiments revealed the identity and specificity of the polysaccharide utilization loci (PULs) that encode individual Sus-like systems that target various plant polysaccharides. Comparative genomic analysis indicated that B. ovatus possesses several unique PULs that enable degradation of hemicellulosic polysaccharides, a phenotype absent from B. thetaiotaomicron. In contrast, the B. thetaiotaomicron genome has been shaped by increased numbers of PULs involved in metabolism of host mucin O-glycans, a phenotype that is undetectable in B. ovatus. Binding studies of the purified sensor domains of PUL-associated hybrid two-component systems in conjunction with transcriptional analyses demonstrate that complex oligosaccharides provide the regulatory cues that induce PUL activation and that each PUL is highly specific for a defined cell wall polymer. These results provide a view of how these species have diverged into different carbohydrate niches by evolving genes that target unique suites of available polysaccharides, a theme that likely applies to disparate bacteria from the gut and other habitats. PMID:22205877

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.

The plant secretory pathway seen through the lens of the cell wall.

PubMed

van de Meene, A M L; Doblin, M S; Bacic, Antony

2017-01-01

Secretion in plant cells is often studied by looking at well-characterised, evolutionarily conserved membrane proteins associated with particular endomembrane compartments. Studies using live cell microscopy and fluorescent proteins have illuminated the highly dynamic nature of trafficking, and electron microscopy studies have resolved the ultrastructure of many compartments. Biochemical and molecular analyses have further informed about the function of particular proteins and endomembrane compartments. In plants, there are over 40 cell types, each with highly specialised functions, and hence potential variations in cell biological processes and cell wall structure. As the primary function of secretion in plant cells is for the biosynthesis of cell wall polysaccharides and apoplastic transport complexes, it follows that utilising our knowledge of cell wall glycosyltransferases (GTs) and their polysaccharide products will inform us about secretion. Indeed, this knowledge has led to novel insights into the secretory pathway, including previously unseen post-TGN secretory compartments. Conversely, our knowledge of trafficking routes of secretion will inform us about polarised and localised deposition of cell walls and their constituent polysaccharides/glycoproteins. In this review, we look at what is known about cell wall biosynthesis and the secretory pathway and how the different approaches can be used in a complementary manner to study secretion and provide novel insights into these processes.

The Multifaceted Effects of Polysaccharides Isolated from Dendrobium huoshanense on Immune Functions with the Induction of Interleukin-1 Receptor Antagonist (IL-1ra) in Monocytes

PubMed Central

Lin, Juway; Chang, Ya-Jen; Yang, Wen-Bin; Yu, Alice L.; Wong, Chi-Huey

2014-01-01

Dendrobium huoshanense is a valuable and versatile Chinese herbal medicine with the anecdotal claims of cancer prevention and anti-inflammation. However, its immunological activities are limited to in vitro studies on a few cytokines and immune cell functions. First, we investigated the effects of polysaccharides isolated from DH (DH-PS) on inducing a panel of cytokines/chemokines in mice in vivo and human in vitro. We found that DH polysaccharides (DH-PS) induced TH1, TH2, inflammatory cytokines and chemokines in mouse in vivo and human cells in vitro. Secondly, we demonstrated that DH-PS expanded mouse splenocytes in vivo including CD4+ T cells, CD8+ T cells, B cells, NK cells, NKT cells, monocytes/macrophages, granulocytes and regulatory T cells. Notably, DH-PS induced an anti-inflammatory molecule, IL-1ra, in mouse and human immune cells, especially monocytes. The serum level of IL-1ra elicited by the injection of DH-PS was over 10 folds of IL-1β, suggesting that DH-PS-induced anti-inflammatory activities might over-ride the inflammatory ones mediated by IL-1β. The signaling pathways of DH-PS-induced IL-1ra production was shown to involve ERK/ELK, p38 MAPK, PI3K and NFκB. Finally, we observed that IL-1ra level induced by DH-PS was significantly higher than that by F3, a polysaccharide extract isolated from another popular Chinese herbal medicine, Ganoderma lucidum. These results indicated that DH-PS might have potential applications for ameliorating IL-1-induced pathogenic conditions. PMID:24705413

Gum arabic glycoprotein is a twisted hairy rope. A new model based on O-galactosylhydroxyproline as the polysaccharide attachment site

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

Wu Qi; Fong, C.; Lamport, D.T.A.

1991-07-01

Separation of the wound exudate from Acacia senegal (L.) Willd., gum arabic, on a preparative Superose-6 column gave two major fractions: a high molecular weight gum arabic glyco-protein (GAGP) containing about 90% carbohydrate and a lower molecular weight heterogeneous gum arabic polysaccharide fraction. Hydrogen fluoride-deglycosylation of GAGP gave a large hydroxyproline-rich polypeptide backbone (dGAGP). Alkaline hydrolysis of GAGP showed that most of the carbohydrate was attached to the polypeptide backbone as small hydroxyproline (Hyp)-polysaccharide substituents. The data imply a rodlike molecule with numerous small polysaccharide substituents (attached to 24% of the Hyp residues), regularly arranged along a highly periodic polypeptidemore » backbone based, hypothetically, on a 10 to 12 residue repetitive peptide motif. Thus, a simple statistical model of the gum arabic glycoprotein predicts a repeating polysaccharide substituents will maximize intramolecular hydrogen bonding if aligned along the long axis of the molecule, forming in effect a twisted hairy rope. Electron micrographs of rotary shadowed GAGP molecules support that prediction and may also explain show such apparently large molecules can exit the cell by endwise reptation through the small pores of the primary cell wall.« less

Rising from the Sea: Correlations between Sulfated Polysaccharides and Salinity in Plants

PubMed Central

Aquino, Rafael S.; Grativol, Clicia; Mourão, Paulo A. S.

2011-01-01

High salinity soils inhibit crop production worldwide and represent a serious agricultural problem. To meet our ever-increasing demand for food, it is essential to understand and engineer salt-resistant crops. In this study, we evaluated the occurrence and function of sulfated polysaccharides in plants. Although ubiquitously present in marine algae, the presence of sulfated polysaccharides among the species tested was restricted to halophytes, suggesting a possible correlation with salt stress or resistance. To test this hypothesis, sulfated polysaccharides from plants artificially and naturally exposed to different salinities were analyzed. Our results revealed that the sulfated polysaccharide concentration, as well as the degree to which these compounds were sulfated in halophytic species, were positively correlated with salinity. We found that sulfated polysaccharides produced by Ruppia maritima Loisel disappeared when the plant was cultivated in the absence of salt. However, subjecting the glycophyte Oryza sativa Linnaeus to salt stress did not induce the biosynthesis of sulfated polysaccharides but increased the concentration of the carboxylated polysaccharides; this finding suggests that negatively charged cell wall polysaccharides might play a role in coping with salt stress. These data suggest that the presence of sulfated polysaccharides in plants is an adaptation to high salt environments, which may have been conserved during plant evolution from marine green algae. Our results address a practical biological concept; additionally, we suggest future strategies that may be beneficial when engineering salt-resistant crops. PMID:21552557

Rising from the sea: correlations between sulfated polysaccharides and salinity in plants.

PubMed

Aquino, Rafael S; Grativol, Clicia; Mourão, Paulo A S

2011-04-28

High salinity soils inhibit crop production worldwide and represent a serious agricultural problem. To meet our ever-increasing demand for food, it is essential to understand and engineer salt-resistant crops. In this study, we evaluated the occurrence and function of sulfated polysaccharides in plants. Although ubiquitously present in marine algae, the presence of sulfated polysaccharides among the species tested was restricted to halophytes, suggesting a possible correlation with salt stress or resistance. To test this hypothesis, sulfated polysaccharides from plants artificially and naturally exposed to different salinities were analyzed. Our results revealed that the sulfated polysaccharide concentration, as well as the degree to which these compounds were sulfated in halophytic species, were positively correlated with salinity. We found that sulfated polysaccharides produced by Ruppia maritima Loisel disappeared when the plant was cultivated in the absence of salt. However, subjecting the glycophyte Oryza sativa Linnaeus to salt stress did not induce the biosynthesis of sulfated polysaccharides but increased the concentration of the carboxylated polysaccharides; this finding suggests that negatively charged cell wall polysaccharides might play a role in coping with salt stress. These data suggest that the presence of sulfated polysaccharides in plants is an adaptation to high salt environments, which may have been conserved during plant evolution from marine green algae. Our results address a practical biological concept; additionally, we suggest future strategies that may be beneficial when engineering salt-resistant crops.

Polysaccharides from the envelopes of heterocysts and spores of the blue-green algae Anabaena variabilis and Cylindrospermum licheniforme

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

Cardemil, L.; Wolk, C.P.

The polysaccharides from the envelopes of heterocysts of Cylindrospermum licheniforme Kutz., and of heterocysts and spores of Anabaena variabilis Kutz., like those from the differentiated cells of Anabaena cylindrica Lemm., have a 1,3-linked backbone consisting of glucosyl and mannosyl residues in a molar ratio of approximately 3:1. As is the case with A. cylindrica the polysaccharides from A. variabilis and from the heterocysts of C. licheniforme have terminal xylosyl and galactosyl residues as side branches. In addition, the polysaccharide from C. licheniforme resembles that from A. cylindrica in having terminal mannosyl residues as side branches (absent from A. variabilis). Themore » polysaccharides from A. variabilis resemble that from A. cylindrica in having glucose-containing side branches (absent from the heterocyst polysaccharide from C. licheniforme), but in contrast to the polysaccharides from the other two species they also have terminal arabinosyl residues as side branches. All of the polysaccharides mentioned appear to be structurally related; we present tentative structures for those not previously investigated. In contrast, the envelope of spores of C. licheniforme contains only a largely 4-linked galactan. The bulk of this envelope is not polysaccharide in nature, and contains aromatic groups.« less

In vivo growth-inhibition of Sarcoma 180 by an alpha-(1-->4)-glucan-beta-(1-->6)-glucan-protein complex polysaccharide obtained from Agaricus blazei Murill.

PubMed

Gonzaga, Maria Leônia Costa; Bezerra, Daniel Pereira; Alves, Ana Paula Negreiros Nunes; de Alencar, Nylane Maria Nunes; Mesquita, Rodney de Oliveira; Lima, Michael Will; Soares, Sandra de Aguiar; Pessoa, Cláudia; de Moraes, Manoel Odorico; Costa-Lotufo, Letícia Veras

2009-01-01

Agaricus blazei Murrill, a native mushroom of Brazil, has been widely consumed in different parts of the world due to its anticancer potential. This effect is generally attributed to its polysaccharides; however, the precise structure of these has not been fully characterized. To better understand the relationship between polysaccharide structures and antitumor activity, we investigated the effect of the intraperitoneally (i.p.) or orally (p.o.) administered alpha-(1-->4)-glucan-beta-(1-->6)-glucan-protein complex polysaccharide from A. blazei alone or in association with 5-fluorouracil (5-FU) in tumor growth using Sarcoma 180 transplanted mice. Hematological, biochemical, and histopathological analyses were performed in order to evaluate the toxicological aspects of the polysaccharide treatment. The polysaccharide had no direct cytotoxic action on tumor cells in vitro. However, the polysaccharide showed strong in vivo antitumor effect. Thus, the tumor growth-inhibitory effect of the polysaccharide is apparently due to host-mediated mechanisms. The histopathological analysis suggests that the liver and the kidney were not affected by polysaccharide treatment. Neither enzymatic activity of transaminases (AST and ALT) nor urea levels were significantly altered. In hematological analysis, leucopeny was observed after 5-FU treatment, but this effect was prevented when the treatment was associated with the polysaccharide. In conclusion, this polysaccharide probably could explain the ethnopharmacological use of this mushroom in the treatment of cancer.

The Dietary Polysaccharide Maltodextrin Promotes Salmonella Survival and Mucosal Colonization in Mice

PubMed Central

Nickerson, Kourtney P.; Homer, Craig R.; Kessler, Sean P.; Dixon, Laura J.; Kabi, Amrita; Gordon, Ilyssa O.; Johnson, Erin E.; de la Motte, Carol A.; McDonald, Christine

2014-01-01

In the latter half of the 20th century, societal and technological changes led to a shift in the composition of the American diet to include a greater proportion of processed, pre-packaged foods high in fat and carbohydrates, and low in dietary fiber (a “Western diet”). Over the same time period, there have been parallel increases in Salmonella gastroenteritis cases and a broad range of chronic inflammatory diseases associated with intestinal dysbiosis. Several polysaccharide food additives are linked to bacterially-driven intestinal inflammation and may contribute to the pathogenic effects of a Western diet. Therefore, we examined the effect of a ubiquitous polysaccharide food additive, maltodextrin (MDX), on clearance of the enteric pathogen Salmonella using both in vitro and in vivo infection models. When examined in vitro, murine bone marrow-derived macrophages exposed to MDX had altered vesicular trafficking, suppressed NAPDH oxidase expression, and reduced recruitment of NADPH oxidase to Salmonella-containing vesicles, which resulted in persistence of Salmonella in enlarged Rab7+ late endosomal vesicles. In vivo, mice consuming MDX-supplemented water had a breakdown of the anti-microbial mucous layer separating gut bacteria from the intestinal epithelium surface. Additionally, oral infection of these mice with Salmonella resulted in increased cecal bacterial loads and enrichment of lamina propria cells harboring large Rab7+ vesicles. These findings indicate that consumption of processed foods containing the polysaccharide MDX contributes to suppression of intestinal anti-microbial defense mechanisms and may be an environmental priming factor for the development of chronic inflammatory disease. PMID:25000398

Microbial and genomic characterization of Geobacillus thermodenitrificans OS27, a marine thermophile that degrades diverse raw seaweeds.

PubMed

Fujii, Kenta; Tominaga, Yurie; Okunaka, Jyumpei; Yagi, Hisashi; Ohshiro, Takashi; Suzuki, Hirokazu

2018-06-01

Seaweeds are a nonlignocellulosic biomass, but they are often abundant in unique polysaccharides that common microbes can hardly utilize; therefore, polysaccharide degradation is key for the full utilization of seaweed biomass. Here, we isolated 13 thermophiles from seaweed homogenates that had been incubated at high temperature. All of the isolates were Gram-positive and preferentially grew at 60-70 °C. Most formed endospores and were tolerant to seawater salinity. Despite different sources, all isolates were identical regarding 16S rRNA gene sequences and were categorized as Geobacillus thermodenitrificans. Their growth occurred on seaweed polysaccharides with different profiles but required amino acids and/or vitamins, implying that they existed as proliferative cells by utilizing nutrients on seaweed viscous surfaces. Among 13 isolates, strain OS27 was further characterized to show that it can utilize a diverse range of seaweed polysaccharides and hemicelluloses. Notably, strain OS27 degraded raw seaweeds while releasing soluble saccharides. The degradation seemed to depend on enzymes that were extracellularly produced in an inducible manner. The strain could be genetically modified to produce heterologous endoglucanase, providing a transformant that degrades more diverse seaweeds with higher efficiency. The draft sequences of the OS27 genome contained 3766 coding sequences, which included intact genes for 28 glycoside hydrolases and many hypothetical proteins unusual among G. thermodenitrificans. These results suggest that G. thermodenitrificans OS27 serves as a genetic resource for thermostable enzymes to degrade seaweeds and potentially as a microbial platform for high temperature seaweed biorefinery via genetic modification.

Optimized extraction of polysaccharides from corn silk by pulsed electric field and response surface quadratic design.

PubMed

Zhao, Wenzhu; Yu, Zhipeng; Liu, Jingbo; Yu, Yiding; Yin, Yongguang; Lin, Songyi; Chen, Feng

2011-09-01

Corn silk is a traditional Chinese herbal medicine, which has been widely used for treatment of some diseases. In this study the effects of pulsed electric field on the extraction of polysaccharides from corn silk were investigated. Polysaccharides in corn silk were extracted by pulsed electric field and optimized by response surface methodology (RSM), based on a Box-Behnken design (BBD). Three independent variables, including electric field intensity (kV cm(-1) ), ratio of liquid to raw material and pulse duration (µs), were investigated. The experimental data were fitted to a second-order polynomial equation and also profiled into the corresponding 3-D contour plots. Optimal extraction conditions were as follows: electric field intensity 30 kV cm(-1) , ratio of liquid to raw material 50, and pulse duration 6 µs. Under these condition, the experimental yield of extracted polysaccharides was 7.31% ± 0.15%, matching well with the predicted value. The results showed that a pulsed electric field could be applied to extract value-added products from foods and/or agricultural matrix. Copyright © 2011 Society of Chemical Industry.

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.

Ancient acquisition of "alginate utilization loci" by human gut microbiota.

PubMed

Mathieu, Sophie; Touvrey-Loiodice, Mélanie; Poulet, Laurent; Drouillard, Sophie; Vincentelli, Renaud; Henrissat, Bernard; Skjåk-Bræk, Gudmund; Helbert, William

2018-05-23

In bacteria from the phylum Bacteroidetes, the genes coding for enzymes involved in polysaccharide degradation are often colocalized and coregulated in so-called "polysaccharide utilization loci" (PULs). PULs dedicated to the degradation of marine polysaccharides (e.g. laminaran, ulvan, alginate and porphyran) have been characterized in marine bacteria. Interestingly, the gut microbiome of Japanese individuals acquired, by lateral transfer from marine bacteria, the genes involved in the breakdown of porphyran, the cell wall polysaccharide of the red seaweed used in maki. Sequence similarity analyses predict that the human gut microbiome also encodes enzymes for the degradation of alginate, the main cell wall polysaccharide of brown algae. We undertook the functional characterization of diverse polysaccharide lyases from family PL17, frequently found in marine bacteria as well as those of human gut bacteria. We demonstrate here that this family is polyspecific. Our phylogenetic analysis of family PL17 reveals that all alginate lyases, which have all the same specificity and mode of action, cluster together in a very distinct subfamily. The alginate lyases found in human gut bacteria group together in a single clade which is rooted deeply in the PL17 tree. These enzymes were found in PULs containing PL6 enzymes, which also clustered together in the phylogenetic tree of PL6. Together, biochemical and bioinformatics analyses suggest that acquisition of this system appears ancient and, because only traces of two successful transfers were detected upon inspection of PL6 and PL17 families, the pace of acquisition of marine polysaccharide degradation system is probably very slow.

Fever-range hyperthermia inhibits cells immune response to protein-bound polysaccharides derived from Coriolus versicolor extract.

PubMed

Pawlikowska, Małgorzata; Jędrzejewski, Tomasz; Piotrowski, Jakub; Kozak, Wiesław

2016-12-01

The aim of the study was to explore whether fever-range hyperthermia (FRH) might enhance the anticancer and immunoregulatory activities of protein-bound polysaccharides (PBP), a class of fungus derived immunomodifiers used in the cancer adjuvant therapy. Blood lymphocytes and breast cancer cells (MCF-7) were cultured at 39.5°C in humidified atmosphere containing 5% CO 2 for 2h. After rested at 37°C for 6h, the cells were treated with PBP extract at 100- and 300μg/ml concentration. After indicated time, the proliferative response was analyzed and cytokine mRNA expression assessment was performed by qRT-PCR. In animal model, the FRH was induced by placing rats in the Homeothermic Controller with heating blanket. Animals were heated until Tb reached 39.5°C (±0.2°C) and were maintained at this temperature for 30min. The protein-bound polysaccharides solution was injected i.p. at a dose of 100 mg/kg 6h post FRH. Twenty four hours after treatment, the blood was collected and cytokines expression analysis were performed. The results have shown that fever-range hyperthermia has an inhibitory effect on PBP extract-induced proliferative response of blood lymphocytes, as well as IL-1β and IL-6 mRNA expression. Moreover, the temperature of 39.5°C blocks PBP-induced cytotoxicity against MCF-7 cells, which correlates with significant reduction in TNF-α level. Combined treatment of rats (FRH+PBP) results in decrease of IL-1β, IL-6 and TNF-α mRNA expression in peripheral blood mononuclear cells compared to cells derived from rats treated with protein-bound polysaccharides extract alone. This study demonstrates that fever-range temperature inhibits immunostimulatory as well as anticancer effects mediated by protein-bound polysaccharides. Copyright © 2016. Published by Elsevier Ltd.

Dual stimuli polysaccharide nanovesicles for conjugated and physically loaded doxorubicin delivery in breast cancer cells.

PubMed

Pramod, P S; Shah, Ruchira; Jayakannan, Manickam

2015-04-21

The present work reports the development of pH and enzyme dual responsive polysaccharide vesicular nano-scaffolds for the administration of doxorubicin via physical loading and polymer-drug conjugation to breast cancer cells. Dextran was suitably modified with a renewable resource 3-pentadecyl phenol unit through imine and aliphatic ester chemical linkages that acted as pH and esterase enzyme stimuli, respectively. These dual responsive polysaccharide derivatives self-organized into 200 ± 10 nm diameter nano-vesicles in water. The water soluble anticancer drug doxorubicin (DOX·HCl) was encapsulated in the hydrophilic pocket to produce core-loaded polysaccharide vesicles whereas chemical conjugation produced DOX anchored at the hydrophobic layer of the dextran nano-vesicles. In vitro studies revealed that about 70-80% of the drug was retained under circulatory conditions at pH = 7.4 and 37 °C. At a low pH of 6.0 to 5.0 and in the presence of esterase; both imine and ester linkages were cleaved instantaneously to release 100% of the loaded drugs. Cytotoxicity assays on Wild Type Mouse Embryonic Fibroblasts (WTMEFs) confirmed the non-toxicity of the newly developed dextran derivatives at up to 500 μg mL(-1) in PBS. MTT assays on fibroblast cells revealed that DOX·HCl loaded nano-vesicles exhibited better killing abilities than DOX conjugated polymer nano-vesicles. Both DOX loaded and DOX conjugated nano-vesicles were found to show significant killing in breast cancer cells (MCF 7). Confocal microscopy images confirmed the uptake of DOX loaded (or conjugated) nano-vesicles by cells compared to free DOX. Thus, the newly developed pH and enzyme dual responsive polysaccharide vesicular assemblies are potential drug vectors for the administration of DOX in both loaded and chemically conjugated forms for the efficient killing of breast cancer cells.

Chemical characterization of Pleurotus eryngii polysaccharide and its tumor-inhibitory effects against human hepatoblastoma HepG-2 cells.

PubMed

Ren, Daoyuan; Wang, Ning; Guo, Jianjun; Yuan, Li; Yang, Xingbin

2016-03-15

This study was designed to investigate the chemical characterization and antitumor effects of Pleurotus eryngii polysaccharides (PEP). The crude PEP was fractionated into two fractions, namely PEP-1 and PEP-2. HPLC analysis showed that PEP-1 and PEP-2 were heteropolysaccharides mainly composed of glucose with the average molecular weights of 2.54×10(4)Da (PEP-1) and 4.63×10(5)Da (PEP-2), respectively. High molecular mass PEP-2 was shown to exhibit stronger growth inhibition against human hepatoblastoma HepG-2 cells in comparison with PEP-1. Flow cytometric analysis showed that PEP-2 exerted a stimulatory effect on apoptosis of HepG-2 cells, and induced the cell-cycle arrest at the S-phase, with the observation of intracellular ROS production. These findings suggest that the polysaccharides, especially PEP-2, are very important nutritional ingredients responsible for the anticancer health benefits of P. eryngii. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Bacteroides fragilis cell envelope: quarterback, linebacker, coach-or all three?

PubMed

Pumbwe, Lilian; Skilbeck, Christopher A; Wexler, Hannah M

2006-01-01

Bacteroides fragilis is an anaerobic commensal constituting only 1-2% of the micro-flora of the human gastrointestinal tract, yet it is the predominant anaerobic isolate in cases of intraabdominal sepsis and bacteremia. B. fragilis can play two roles in the host: in its role as friendly commensal, it must be able to establish itself in the host intestinal mucosa, to utilize and process polysaccharides for use by the host, and to resist the noxious effects of bile salts. In its role as pathogen, it must be able to attach itself to the site of infection, evade killing mechanisms by host defense, withstand antimicrobial treatment and produce factors that damage host tissue. The cell envelope of B. fragilis, likewise, must be able to function in the roles of aggressor, defender and strategist in allowing the organism to establish itself in the host--whether as friend or foe. Recent studies of the genomes and proteomes of the genus Bacteroides suggest that these organisms have evolved strategies to survive and dominate in the overcrowded gastrointestinal neighborhood. Analysis of the proteomes of B. fragilis and Bacteroides thetaiotaomicron demonstrates both a tremendous capacity to use a wide range of dietary polysaccharides, and the capacity to create variable surface antigenicities by multiple DNA inversion systems. The latter characteristic is particularly pronounced in the species B. fragilis, which is more frequently found at the mucosal surface (i.e., often the site of attack by host defenses). The B. fragilis cell envelope undergoes major protein expression and ultrastructural changes in response to stressors such as bile or antimicrobial agents. These agents may also act as signals for attachment and colonization. Thus the bacterium manages its surface characteristics to enable it to bind to its target, to use the available nutrients, and to avoid or evade hostile forces (host-derived or external) in its multiple roles.

Adeno-associated virus type 2 binding study on model heparan sulfate surface

NASA Astrophysics Data System (ADS)

Negishi, Atsuko; Liu, Jian; McCarty, Douglas; Samulski, Jude; Superfine, Richard

2003-11-01

Understanding the mechanisms involved in virus infections is useful in its application in areas such as gene therapy, drug development and delivery, and biosensors. In collaboration with UNC Gene Therapy Center and School of Pharmacy, we are specifically looking at the interaction between human parvovirus adeno-associated virus type 2 (AAV2), a potential viral vector, and heparan sulfate proteoglycan (HSPG), a known cell surface receptor for AAV2. Recent development in glycobiology has shown that some protein-polysaccharide binding is sugar sequence dependent. Heparan sulfate (HS) is a polysaccharide chain of sulfated iduronic/glucuronic and sulfate glucosamine residues and can be differentiated into sequence specific structures by enzymes. These enzymatic modifications, known as heparan sulfate sulfotransferase modified modifications, have been shown to change the biological nature of heparan sulfate such as specific binding to proteins and viruses. For understanding HS-assisted viral infection mechanisms, we are interested in investigating the binding affinity and stability of AAV to different HS structures. We have developed a model heparan sulfate surface in which AAV adsorption studies are done and analyzed using the atomic force microscope (AFM). In addition, a miniArray assay has been created to facilitate to this study. Adsorption studies are done in 4 white LED wells with approximately 3 mm2 reaction areas which minimize sample use and waste.

Purification, characterization and anti-proliferation activities of polysaccharides extracted from Viscum coloratum (Kom.) Nakai.

PubMed

Chai, Yangyang; Zhao, Min

2016-09-20

Three polysaccharides, VCP1, VCP2 and VCP3 were isolated from Viscum coloratum (Kom.) Nakai using DEAE-cellulose chromatography. VCP1 (32KDa) was composed of glucose, galactose, arabinose, rhamnose and mannose, while VCP2 (280KDa) and VCP3 (21KDa) were consisted of glucose, galactose, arabinose, rhamnose, mannose, glucuronic acid and galacturonic acid. The optical rotation was measured at 20+1°C. The characteristic absorptive bands of purified fraction were determined by FT-IR. (13)C NMR spectroscopy analysis showed that VCP1 was a neutral polysaccharide, and VCP2 and VCP3 were RG-I type pectin. The linkage patterns of VCP2 were evaluated by methylation analysis: 1,5-linked Araf, 1,4-linked Galp, 1,2-linked Rhap, and 1,2,4-linked Rhap. The degree of esterification was 50%. The anti-proliferation ability against HepG2 cells and HepG2.2.15 cells of VCP2 was stronger than VCP1 and VCP3. So the polysaccharides from Viscum coloratum (Kom.) Nakai could be used as potential natural sources with inhibiting tumor cells proliferation. Copyright © 2016 Elsevier Ltd. All rights reserved.

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.

Structure Characterization and Immunomodulating Effects of Polysaccharides Isolated from Dendrobium officinale.

PubMed

Wei, Wei; Feng, Lei; Bao, Wan-Rong; Ma, Dik-Lung; Leung, Chung-Hang; Nie, Shao-Ping; Han, Quan-Bin

2016-02-03

A crude polysaccharide fraction (cDOP) has been determined to be the characteristic marker of Dendrobium officinale, an expensive tea material in Asia, but its chemistry and bioactivity have not been studied. In work reported here, cDOP was destarched (DOP, 90% yield) and separated into two subfraction polysaccharides, DOPa and DOPb, which were characterized by monosaccharide composition and methylation analyses and spectral analyses (FT-IR and (1)H and (13)C NMR). Both are composed of mannose and glucose at similar ratios and have a similar structure with a backbone of 1,4-linked β-D-mannopyranosyl and β-D-glucopyranosyl residues. Significant differences were observed only in their molecular weights. Bioassay using mouse macrophage cell line RAW264.7 indicated that DOP and its two subfractions enhance cell proliferation, TNF-α secretion, and phagocytosis in a dose-dependent manner. They also induced the proliferation of lymphocytes alone and with mitogens. DOPa and DOPb are thus proven to be major, active polysaccharide markers of D. officinale.

Regulation of RAW 264.7 cell-mediated immunity by polysaccharides from Agaricus blazei Murill via the MAPK signal transduction pathway.

PubMed

Cheng, Feier; Yan, Xiaoyan; Zhang, Miaoqing; Chang, Mingchang; Yun, Shaojun; Meng, Junlong; Liu, Jingyu; Feng, Cui-Ping

2017-04-19

Agaricus blazei Murill (ABM) is a common anticancer folk remedy. Its active ingredients, i.e., polysaccharides, have been isolated and exhibit indirect tumor-suppressing activity via immunological activation. The effects of polysaccharides derived from A. blazei Murill (ABMP) on RAW 264.7 cells were examined by western blotting and real-time reverse transcription polymerase chain reaction (RT-PCR). The effects of 500, 1000, and 2000 μg mL -1 ABMP on the growth of RAW 264.7 cells were evaluated by measuring the OD 490 value; the optimum concentration was found to be 1000 μg mL -1 . Based on the RT-PCR results, the expression levels of JNK, ERK, and p38 decreased substantially in lipopolysaccharide (LPS)-induced RAW 264.7 cells treated with ABMP. In RAW 264.7 cells treated with LPS, the protein expression levels of JNK, ERK, and p38 were decreased, as were the levels of phosphorylated JNK, ERK, and p38. These results indicate that the MAPK signal transduction pathway is a potential mechanism by which ABMP regulates the cell-mediated immunity of RAW 264.7 cells.

Effect of light with different wavelengths on Nostoc flagelliforme cells in liquid culture.

PubMed

Dai, Yu-Jie; Li, Jing; Wei, Shu-Mei; Chen, Nan; Xiao, Yu-Peng; Tan, Zhi-Lei; Jia, Shi-Ru; Yuan, Nan-Nan; Tan, Ning; Song, Yi-Jie

2013-04-01

The effects of lights with different wavelengths on the growth and the yield of extracellular polysaccharides of Nostoc flagelliforme cells were investigated in a liquid cultivation. N. flagelliforme cells were cultured for 16 days in 500 ml conical flasks containing BG11 culture medium under 27 micromol·m-2·s-1 of light intensity and 25 degrees C on a rotary shaker (140 rpm). The chlorophyll a, phycocyanin, allophycocyanin, and phycoerythrin contents in N. flagelliforme cells under the lights of different wavelengths were also measured. It was found that the cell biomass and the yield of polysaccharide changed with different wavelengths of light. The biomass and the yield of extracellular polysaccharides under the red or violet light were higher than those under other light colors. Chlorophyll a, phycocyanin, and allophycocyanin are the main pigments in N. flagelliforme cells. The results showed that N. flagelliforme, like other cyanobacteria, has the ability of adjusting the contents and relative ratio of its pigments with the light quality. As a conclusion, N. flagelliforme cells favor red and violet lights and perform the complementary chromatic adaptation ability to acclimate to the changes of the light quality in the environment.

The consequences of the intracellular retention of pathogen-derived T-cell-independent antigens on protein presentation to T cells.

PubMed

Leyva-Cobián, F; Outschoorn, I M; Carrasco-Marín, E; Alvarez-Domínguez, C

1997-10-01

Intracellular pathogens can be considered as particulate antigens chemically composed of a complex mixture of T-cell-dependent antigens (TD) (peptides and proteins) and T-cell-independent antigens (TI) (glycolipids and complex polysaccharides). A large range of saccharides (from oligosaccharides to complex polysaccharides) derived from pathogenic microorganisms are being isolated and characterized. They are currently implicated in signaling systems and concomitant host-parasite relationships. However, there are not many structure-function relationships described for these pathogens. This is particularly true of polysaccharides. In this report we have reviewed the role of defined TI antigens in the processing and presentation of defined TD antigens to specific T cells by antigen-presenting cells (APC). We also considered the importance of some of the chemical characteristics shared by different carbohydrates implicated in the inhibition of antigen presentation. These findings are discussed in relation to the clear immunopathological consequences of long retention periods of complex carbohydrate molecules derived from intracellular parasites inside certain APC and the absence of antigen presentation impairment in physiological situations such as the removal of senescent or damaged red blood cells by splenic macrophages or intracellular accumulation of carbohydrates in colostrum and milk macrophages during lactation.

Ultrasonic extraction, antioxidant and anticancer activities of novel polysaccharides from Chuanxiong rhizome.

PubMed

Hu, Jie; Jia, Xuejing; Fang, Xiaobin; Li, Peng; He, Chengwei; Chen, Meiwan

2016-04-01

Ultrasonic-assisted extraction technology was employed to prepare Ligusticum chuanxiong Hort polysaccharide. Single factor test and orthogonal experimental design were used to optimize the extraction conditions. The results showed that the optimal extraction conditions consisted of ultrasonic temperature of 80°C, ultrasonic time of 40 min and water to raw material ratio of 30 mL/g. Three novel polysaccharides fractions, LCX0, LCX1 and LCX2, were isolated and purified from the crude polysaccharides using DEAE-52 cellulose and Sephadex G-100 column chromatography. The molecular weight and monosaccharide composition of three LCX polysaccharides fractions were analyzed with gel permeation chromatography (GPC) and HPLC analysis, respectively. Furthermore, the antioxidant and in vitro anticancer activities of the polysaccharides were investigated. Compared with LCX0, LCX2 and LCX1 showed relative higher antioxidant activity and inhibitory activity to the growth of HepG2, SMMC7721, A549 and HCT-116 cells. It is suggested that the novel polysaccharides from rhizome of L. chuanxiong could be promising bioactive macromolecules for biomedical use. Copyright © 2016. Published by Elsevier B.V.

Bacterial autolysins trim cell surface peptidoglycan to prevent detection by the Drosophila innate immune system

PubMed Central

Atilano, Magda Luciana; Pereira, Pedro Matos; Vaz, Filipa; Catalão, Maria João; Reed, Patricia; Grilo, Inês Ramos; Sobral, Rita Gonçalves; Ligoxygakis, Petros; Pinho, Mariana Gomes; Filipe, Sérgio Raposo

2014-01-01

Bacteria have to avoid recognition by the host immune system in order to establish a successful infection. Peptidoglycan, the principal constituent of virtually all bacterial surfaces, is a specific molecular signature recognized by dedicated host receptors, present in animals and plants, which trigger an immune response. Here we report that autolysins from Gram-positive pathogenic bacteria, enzymes capable of hydrolyzing peptidoglycan, have a major role in concealing this inflammatory molecule from Drosophila peptidoglycan recognition proteins (PGRPs). We show that autolysins trim the outermost peptidoglycan fragments and that in their absence bacterial virulence is impaired, as PGRPs can directly recognize leftover peptidoglycan extending beyond the external layers of bacterial proteins and polysaccharides. The activity of autolysins is not restricted to the producer cells but can also alter the surface of neighboring bacteria, facilitating the survival of the entire population in the infected host. DOI: http://dx.doi.org/10.7554/eLife.02277.001 PMID:24692449

The interaction of lipopolysaccharide-coated polystyrene particle with membrane receptor proteins on macrophage measured by optical tweezers

NASA Astrophysics Data System (ADS)

Wei, Ming-Tzo; Hua, Kuo-Feng; Hsu, Jowey; Karmenyan, Artashes; Hsu, Hsien-Yeh; Chiou, Arthur

2006-08-01

Lipopolysaccharide (LPS) is one of the cell wall components of Gram-positive bacteria recognized by and interacted with receptor proteins such as CD14 on macrophage cells. Such a process plays an important role in our innate immune system. In this paper, we report the application of optical tweezers (λ = 1064nm Gaussian beam focused by a water-immersed objective lens with N.A. = 1.0) to the study of the dynamics of the binding of a LPS-coated polystyrene particle (diameter = 1.5μm) onto the plasma membrane of a macrophage cell. We demonstrated that the binding rate increased significantly when the macrophage cell was pre-treated with the extract of Reishi polysaccharides (EORP) which has been shown to enhance the cell surface expression of CD14 (receptor of LPS) on macrophage cells.

Polysaccharide Degradation Capability of Actinomycetales Soil Isolates from a Semiarid Grassland of the Colorado Plateau.

PubMed

Yeager, Chris M; Gallegos-Graves, La Verne; Dunbar, John; Hesse, Cedar N; Daligault, Hajnalka; Kuske, Cheryl R

2017-03-15

Among the bacteria, members of the order Actinomycetales are considered quintessential degraders of complex polysaccharides in soils. However, studies examining complex polysaccharide degradation by Actinomycetales (other than Streptomyces spp.) in soils are limited. Here, we examine the lignocellulolytic and chitinolytic potential of 112 Actinomycetales strains, encompassing 13 families, isolated from a semiarid grassland of the Colorado Plateau in Utah. Members of the Streptomycetaceae , Pseudonocardiaceae , Micromonosporaceae , and Promicromonosporaceae families exhibited robust activity against carboxymethyl cellulose, xylan, chitin, and pectin substrates (except for low/no pectinase activity by the Micromonosporaceae ). When incubated in a hydrated mixture of blended Stipa and Hilaria grass biomass over a 5-week period, Streptomyces and Saccharothrix (a member of the Pseudonocardiaceae ) isolates produced high levels of extracellular enzyme activity, such as endo- and exocellulase, glucosidase, endo- and exoxylosidase, and arabinofuranosidase. These characteristics make them well suited to degrade the cellulose and hemicellulose components of grass cell walls. On the basis of the polysaccharide degradation profiles of the isolates, relative abundance of Actinomycetales sequences in 16S rRNA gene surveys of Colorado Plateau soils, and analysis of genes coding for polysaccharide-degrading enzymes among 237 Actinomycetales genomes in the CAZy database and 5 genomes from our isolates, we posit that Streptomyces spp. and select members of the Pseudonocardiaceae and Micromonosporaceae likely play an important role in the degradation of hemicellulose, cellulose, and chitin substances in dryland soils. IMPORTANCE Shifts in the relative abundance of Actinomycetales taxa have been observed in soil microbial community surveys during large, manipulated climate change field studies. However, our limited understanding of the ecophysiology of diverse Actinomycetales taxa in soil systems undermines attempts to determine the underlying causes of the population shifts or their impact on carbon cycling in soil. This study combines a systematic analysis of the polysaccharide degradation potential of a diverse collection of Actinomycetales isolates from surface soils of a semiarid grassland with analysis of genomes from five of these isolates and publicly available Actinomycetales genomes for genes encoding polysaccharide-active enzymes. The results address an important gap in knowledge of Actinomycetales ecophysiology-identification of key taxa capable of facilitating lignocellulose degradation in dryland soils. Information from this study will benefit future metagenomic studies related to carbon cycling in dryland soils by providing a baseline linkage of Actinomycetales phylogeny with lignocellulolytic functional potential. Copyright © 2017 American Society for Microbiology.

Polysaccharide Degradation Capability of Actinomycetales Soil Isolates from a Semiarid Grassland of the Colorado Plateau

PubMed Central

Gallegos-Graves, La Verne; Dunbar, John; Hesse, Cedar N.; Daligault, Hajnalka; Kuske, Cheryl R.

2017-01-01

ABSTRACT Among the bacteria, members of the order Actinomycetales are considered quintessential degraders of complex polysaccharides in soils. However, studies examining complex polysaccharide degradation by Actinomycetales (other than Streptomyces spp.) in soils are limited. Here, we examine the lignocellulolytic and chitinolytic potential of 112 Actinomycetales strains, encompassing 13 families, isolated from a semiarid grassland of the Colorado Plateau in Utah. Members of the Streptomycetaceae, Pseudonocardiaceae, Micromonosporaceae, and Promicromonosporaceae families exhibited robust activity against carboxymethyl cellulose, xylan, chitin, and pectin substrates (except for low/no pectinase activity by the Micromonosporaceae). When incubated in a hydrated mixture of blended Stipa and Hilaria grass biomass over a 5-week period, Streptomyces and Saccharothrix (a member of the Pseudonocardiaceae) isolates produced high levels of extracellular enzyme activity, such as endo- and exocellulase, glucosidase, endo- and exoxylosidase, and arabinofuranosidase. These characteristics make them well suited to degrade the cellulose and hemicellulose components of grass cell walls. On the basis of the polysaccharide degradation profiles of the isolates, relative abundance of Actinomycetales sequences in 16S rRNA gene surveys of Colorado Plateau soils, and analysis of genes coding for polysaccharide-degrading enzymes among 237 Actinomycetales genomes in the CAZy database and 5 genomes from our isolates, we posit that Streptomyces spp. and select members of the Pseudonocardiaceae and Micromonosporaceae likely play an important role in the degradation of hemicellulose, cellulose, and chitin substances in dryland soils. IMPORTANCE Shifts in the relative abundance of Actinomycetales taxa have been observed in soil microbial community surveys during large, manipulated climate change field studies. However, our limited understanding of the ecophysiology of diverse Actinomycetales taxa in soil systems undermines attempts to determine the underlying causes of the population shifts or their impact on carbon cycling in soil. This study combines a systematic analysis of the polysaccharide degradation potential of a diverse collection of Actinomycetales isolates from surface soils of a semiarid grassland with analysis of genomes from five of these isolates and publicly available Actinomycetales genomes for genes encoding polysaccharide-active enzymes. The results address an important gap in knowledge of Actinomycetales ecophysiology—identification of key taxa capable of facilitating lignocellulose degradation in dryland soils. Information from this study will benefit future metagenomic studies related to carbon cycling in dryland soils by providing a baseline linkage of Actinomycetales phylogeny with lignocellulolytic functional potential. PMID:28087533

Pharmacological evaluation for anticancer and immune activities of a novel polysaccharide isolated from Boletus speciosus Frost.

PubMed

Hou, Yiling; Ding, Xiang; Hou, Wanru; Song, Bo; Wang, Ting; Wang, Fang; Li, Jian; Zeng, Yichun; Zhong, Jie; Xu, Ting; Zhu, Hongqing

2014-04-01

The fungal polysaccharides have been revealed to exhibit a variety of biological activities, including antitumor, immune-stimulation and antioxidation activities. In the present study, the immune and anticancer activities of a novel polysaccharide, BSF-A, isolated from Boletus speciosus Frost was investigated. The inhibitory rate of S180 tumors in mice treated with 40 mg/kg BSF-A reached 62.449%, which was the highest rate from the three doses administered; this may be comparable to mannatide. The antitumor activity of BSF-A is commonly considered to be a consequence of the stimulation of the cell-mediated immune response, as it may significantly promote the macrophage cells in the dose range of 100-400 µg/ml in vitro. The levels of the cytokines, IL-6, IL-1β and TNF-α, and nitric oxide, induced by BSF-A treatment at varying concentrations in the macrophage cells were similar to the levels in the cells treated with lipopolysaccharide. There was weak expression of the TNF-α, IL-6, IL-1β and inducible nitric oxide synthase mRNA in the untreated macrophages, but this increased significantly in a dose-dependent manner in the BSF-A-treated cells. BSF-A also had a time- and dose-dependent effect on the growth inhibition of the Hep-2 cells, with the concentration of 400 µg/ml having the highest inhibitory rate. A quantitative PCR array analysis of the gene expression profiles indicated that BSF-A had anticancer activities that affected cell apoptosis in the Hep-2 cells. The results obtained in the present study indicated that the purified polysaccharide of Boletus speciosus Frost is a potential source of natural anticancer substances.

Alkali-soluble polysaccharide, isolated from Lentinus edodes, induces apoptosis and G2/M cell cycle arrest in H22 cells through microtubule depolymerization.

PubMed

You, Ru-Xu; Liu, Jin-Yu; Li, Shi-Jun; Wang, Liu; Wang, Kai-Ping; Zhang, Yu

2014-12-01

The aim of the study was to evaluate the pro-apoptotic effects of polysaccharides derived from Lentinus edodes and further elucidated the mechanisms of this action. Our results demonstrated that marked morphological changes of apoptosis were observed after treatment of L. edodes polysaccharides [Lentinan (LTN)]. Moreover, LTN-induced cell apoptosis was characterized by a rapid stimulation of reactive oxygen species production, the loss of mitochondrial membrane potential and an increase in intracellular concentration of Ca(2+) . In addition, the results of the haematoxylin and eosin and TUNEL assay further confirmed that LTN-induced apoptosis in vivo. Furthermore, flow cytometry analysis showed that LTN could arrest the cell cycle at G2/M phase, and immunofluorescence showed LTN caused disruption of microtubule. These results suggest that disruption of cellular microtubule network, arrest of the cell cycle at G2/M phase and induction of apoptosis may be one of the possible mechanisms of anti-tumour effect of LTN. Copyright © 2014 John Wiley & Sons, Ltd.

An antivirally active sulfated polysaccharide from Sargassum horneri (TURNER) C. AGARDH.

PubMed

Hoshino, T; Hayashi, T; Hayashi, K; Hamada, J; Lee, J B; Sankawa, U

1998-07-01

A sulfated polysaccharide was isolated from the hot water extract of a brown alga, Sargassum horneri (TURNER) C. AGARDH. Fucose was detected as the main component sugar of this polysaccharide. This compound showed potent antiviral activity against herpes simplex virus type 1, human cytomegalovirus and human immunodeficiency virus type 1. Time-of-addition experiments suggested that it inhibited not only the initial stages of viral infection, such as attachment to and penetration into host cells, but also later replication stages after virus penetration.

Polysaccharide compositions of collenchyma cell walls from celery (Apium graveolens L.) petioles.

PubMed

Chen, Da; Harris, Philip J; Sims, Ian M; Zujovic, Zoran; Melton, Laurence D

2017-06-15

Collenchyma serves as a mechanical support tissue for many herbaceous plants. Previous work based on solid-state NMR and immunomicroscopy suggested collenchyma cell walls (CWs) may have similar polysaccharide compositions to those commonly found in eudicotyledon parenchyma walls, but no detailed chemical analysis was available. In this study, compositions and structures of cell wall polysaccharides of peripheral collenchyma from celery petioles were investigated. This is the first detailed investigation of the cell wall composition of collenchyma from any plant. Celery petioles were found to elongate throughout their length during early growth, but as they matured elongation was increasingly confined to the upper region, until elongation ceased. Mature, fully elongated, petioles were divided into three equal segments, upper, middle and lower, and peripheral collenchyma strands isolated from each. Cell walls (CWs) were prepared from the strands, which also yielded a HEPES buffer soluble fraction. The CWs were sequentially extracted with CDTA, Na 2 CO 3 , 1 M KOH and 4 M KOH. Monosaccharide compositions of the CWs showed that pectin was the most abundant polysaccharide [with homogalacturonan (HG) more abundant than rhamnogalacturonan I (RG-I) and rhamnogalacturonan II (RG-II)], followed by cellulose, and other polysaccharides, mainly xyloglucans, with smaller amounts of heteroxylans and heteromannans. CWs from different segments had similar compositions, but those from the upper segments had slightly more pectin than those from the lower two segments. Further, the pectin in the CWs of the upper segment had a higher degree of methyl esterification than the other segments. In addition to the anticipated water-soluble pectins, the HEPES-soluble fractions surprisingly contained large amounts of heteroxylans. The CDTA and Na 2 CO 3 fractions were rich in HG and RG-I, the 1 M KOH fraction had abundant heteroxylans, the 4 M KOH fraction was rich in xyloglucan and heteromannans, and cellulose was predominant in the final residue. The structures of the xyloglucans, heteroxylans and heteromannans were deduced from the linkage analysis and were similar to those present in most eudicotyledon parenchyma CWs. Cross polarization with magic angle spinning (CP/MAS) NMR spectroscopy showed no apparent difference in the rigid and semi-rigid polysaccharides in the CWs of the three segments. Single-pulse excitation with magic-angle spinning (SPE/MAS) NMR spectroscopy, which detects highly mobile polysaccharides, showed the presence of arabinan, the detailed structure of which varied among the cell walls from the three segments. Celery collenchyma CWs have similar polysaccharide compositions to most eudicotyledon parenchyma CWs. However, celery collenchyma CWs have much higher XG content than celery parenchyma CWs. The degree of methyl esterification of pectin and the structures of the arabinan side chains of RG-I show some variation in the collenchyma CWs from the different segments. Unexpectedly, the HEPES-soluble fraction contained a large amount of heteroxylans.

Biochemical and genetic characterization of serologically untypable Streptococcus mutans strains isolated from patients with bacteremia.

PubMed

Fujiwara, T; Nakano, K; Kawaguchi, M; Ooshima, T; Sobue, S; Kawabata, S; Nakagawa, I; Hamada, S

2001-10-01

Four out of 522 streptococcal isolates from the peripheral blood of patients with bacteremia exhibited typical properties of Streptococcus mutans in terms of sucrose-dependent adhesion, expression of glucosyltransferases, fermentation profiles of sugars, the presence of surface protein antigen, and DNA-DNA hybridization. Two strains were determined as serotype f and e by immunodiffusion, whereas the other two isolates did not react with the specific antiserum to S. mutans serotype c. e. or f of the eight different serotypes of mutans streptococci. The latter two untypable isolates, however, expressed a new antigenic determinant that was different from serotype c/e/f specificity as revealed by immunodiffusion. Analysis of the cell wall polysaccharides revealed very low contents of glucose in the untypable isolates. Furthermore, Southern blot analysis demonstrated that the untypable strains lacked at least one gene corresponding to a glucose-adding enzyme. These results indicate that the serologically untypable nature is due to the loss of glucosidic residue from the serotype-specific polysaccharide antigens of S. mutans.

Extending Synthetic Routes for Oligosaccharides by Enzyme, Substrate and Reaction Engineering

NASA Astrophysics Data System (ADS)

Seibel, Jürgen; Jördening, Hans-Joachim; Buchholz, Klaus

The integration of all relevant tools for bioreaction engineering has been a recent challenge. This approach should notably favor the production of oligo- and polysaccharides, which is highly complex due to the requirements of regio- and stereoselectivity. Oligosaccharides (OS) and polysaccharides (PS) have found many interests in the fields of food, pharmaceuticals, and cosmetics due to different specific properties. Food, sweeteners, and food ingredients represent important sectors where OS are used in major amounts. Increasing attention has been devoted to the sophisticated roles of OS and glycosylated compounds, at cell or membrane surfaces, and their function, e.g., in infection and cancer proliferation. The challenge for synthesis is obvious, and convenient approaches using cheap and readily available substrates and enzymes will be discussed. We report on new routes for the synthesis of oligosaccharides (OS), with emphasis on enzymatic reactions, since they offer unique properties, proceeding highly regio- and stereoselective in water solution, and providing for high yields in general.

The application of polysaccharide-based nanogels in peptides/proteins and anticancer drugs delivery.

PubMed

Zhang, Lin; Pan, Jifei; Dong, Shibo; Li, Zhaoming

2017-09-01

Finding adequate carriers for proteins/peptides and anticancer drugs delivery has become an urgent need, owing to the growing number of therapeutic macromolecules and the increasing amount of cancer incidence. Polysaccharide-based nanogels have attracted interest as carriers for proteins/peptides and anticancer drugs because of their characteristic properties like biodegradability, biocompatibility, stimuli-responsive behaviour, softness and swelling to help achieve a controlled, triggered response at the target site. In addition, the groups of the polysaccharide backbone are able to be modified to develop functional nanogels. Some polysaccharides have the intrinsic ability to recognise specific cell types, allowing the design of targeted drug delivery systems through receptor-mediated endocytosis. This review is aimed at describing and exploring the potential of polysaccharides that are used in nanogels which can help to deliver proteins/peptides and anticancer drugs.

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

PubMed

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

2017-12-01

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

The sulfated polysaccharide from a marine red microalga as a platform for the incorporation of zinc ions.

PubMed

Netanel Liberman, Gal; Ochbaum, Guy; Malis Arad, Shoshana; Bitton, Ronit

2016-11-05

The cell-wall sulfated polysaccharide of the marine red microalga Porphyridium sp. is a high molecular weight biopolymer that has potential for use as a platform for metal complexation for various applications. This paper describes the structural and rheological characterization and antibacterial activity of the polysaccharide in combination with Zn(2+) (Zn-PS). SAXS and rheology studies indicate that with the addition of ZnCl2 to the sulfated polysaccharide the only change was the increase in viscosity in the entangled regime. The antibacterial activity of Zn-PS solutions was more potent than that of the native polysaccharide against Gram-negative and Gram-positive bacteria. The synergy between the bioactivities of Zn(2+) (which is a key player in wound healing and is active against variety of pathogens) and the unique bioactivities of the polysaccharide (e.g., anti-inflammatory) indicates promising potential for the development of novel products for the pharmaceutical and cosmetics industries. Copyright © 2016. Published by Elsevier Ltd.

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.

Chitosan-coated amyloid fibrils increase adipogenesis of mesenchymal stem cells.

PubMed

Gilbert, Jay; Reynolds, Nicholas P; Russell, Sarah M; Haylock, David; McArthur, Sally; Charnley, Mirren; Jones, Owen G

2017-10-01

Mesenchymal stem cells (MSCs) have the potential to revolutionize medicine due to their ability to differentiate into specific lineages for targeted tissue repair. Development of materials and cell culture platforms that improve differentiation of either autologous or allogenic stem cell sources into specific lineages would enhance clinical utilization of MCSs. In this study, nanoscale amyloid fibrils were evaluated as substrate materials to encourage viability, proliferation, multipotency, and differentiation of MSCs. Fibrils assembled from the proteins lysozyme or β-lactoglobulin, with and without chitosan coatings, were deposited on planar mica surfaces. MSCs were cultured and differentiated on fibril-covered surfaces, as well as on unstructured controls and tissue culture plastic. Expression of CD44 and CD90 proteins indicated that multipotency was maintained for all fibrils, and osteogenic differentiation was similarly comparable among all tested materials. MSCs grown for 7days on fibril-covered surfaces favored multicellular spheroid formation and demonstrated a >75% increase in adipogenesis compared to tissue culture plastic controls, although this benefit could only be achieved if MSCs were transferred to TCP for the final differentiation step. The largest spheroids and greatest tendency to undergo adipogenesis was evidenced among MSCs grown on fibrils coated with the positively-charged polysaccharide chitosan, suggesting that spheroid formation is prompted by both topography and cell-surface interactivity and that there is a connection between multicellular spheroid formation and adipogenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

Immunostimulatory activity of water-extractable polysaccharides from Cistanche deserticola as a plant adjuvant in vitro and in vivo

PubMed Central

Yang, Xiumei; Yang, Yu; Zhao, Gan; Wang, Bin; Wu, Daocheng

2018-01-01

A safe and effective vaccine adjuvant is important in modern vaccines. Various Chinese herbal polysaccharides can activate the immune system. Cistanche deserticola (CD) is a traditional Chinese herb and an adjuvant candidate. Here, we confirmed that water-extractable polysaccharides of CD (WPCD) could modulate immune responses in vitro and in vivo. In a dose-dependent manner, WPCD significantly promoted the maturation and function of murine marrow-derived dendritic cells (BM-DCs) through up-regulating the expression levels of MHC-II, CD86, CD80, and CD40, allogenic T cell proliferation, and the yields of IL-12 and TNF-α via toll-like receptor4 (TLR4), as indicated by in vitro experiments. In addition, its immunomodulatory activity was also observed in mice. WPCD effectively improved the titers of IgG, IgG1 and IgG2a and markedly enhanced the proliferation of T and B cells, the production of IFN-γ and IL-4 in CD4+ T cells and the expression level of IFN-γ in CD8+ T cells better than Alum. Furthermore, WPCD could markedly up-regulate the expression levels of CD40 and CD80 on DCs in spleen and down-regulate the Treg frequency. The study suggests that polysaccharides of Cistanche deserticola are a safe and effective vaccine adjuvant for eliciting both humoral immunity and cellular immunity by activating DCs via TLR4 signaling pathway. PMID:29360858

Statistical optimization of polysaccharide production by submerged cultivation of Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (W.Curt.: Fr.) P. Karst. MTCC 1039 (Aphyllophoromycetideae).

PubMed

Baskar, Gurunathan; Sathya, Shree Rajesh K Lakshmi Jai; Jinnah, Riswana Begum; Sahadevan, Renganathan

2011-01-01

Response surface methodology was employed to optimize the concentration of four important cultivation media components such as cottonseed oil cake, glucose, NH4Cl, and MgSO4 for maximum medicinal polysaccharide yield by Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum MTCC 1039 in submerged culture. The second-order polynomial model describing the relationship between media components and polysaccharide yield was fitted in coded units of the variables. The higher value of the coefficient of determination (R2 = 0.953) justified an excellent correlation between media components and polysaccharide yield, and the model fitted well with high statistical reliability and significance. The predicted optimum concentration of the media components was 3.0% cottonseed oil cake, 3.0% glucose, 0.15% NH4Cl, and 0.045% MgSO4, with the maximum predicted polysaccharide yield of 819.76 mg/L. The experimental polysaccharide yield at the predicted optimum media components was 854.29 mg/L, which was 4.22% higher than the predicted yield.

Effect of pretreatments on isolation of bioactive polysaccharides from spent coffee grounds using subcritical water.

PubMed

Getachew, Adane Tilahun; Cho, Yeon Jin; Chun, Byung Soo

2018-04-01

In this study, we used a novel approach to recover polysaccharide from spent coffee ground (SCG) by combining pretreatments and subcritical water hydrolysis (SCWH). The independent variables which affect SCWH were optimized using response surface methodology. The highest yield of SCG polysaccharides (SCGPSs) (18.25 ± 0.21%) was obtained using ultrasonic pretreatment and SCWH conditions of temperature (178.85 °C), pressure (20 bar), and extraction time (5 min). The extracted SCGPSs showed high antioxidant activity as measured using ABTS + and DPPH radical scavenging assay with IC 50 values of 1.83 ± 0.03 and 2.66 ± 0.13 mg/ml respectively. SCGPSs also showed in vitro hypoglycemic activities. The structural and thermal characterization of the polysaccharide showed that the extracted polysaccharide has a typical carbohydrate features. The results of this study suggested that the extracted polysaccharide could have a potential application in food and related industries. Copyright © 2017 Elsevier B.V. All rights reserved.

Preparation and characterization of a novel conformed bipolymer paclitaxel-nanoparticle using tea polysaccharides and zein.

PubMed

Li, Shuqin; Wang, Xiuming; Li, Weiwei; Yuan, Guoqi; Pan, Yuxiang; Chen, Haixia

2016-08-01

To improve the aqueous solubility of the anticancer agent paclitaxel (PTX), a newly conformed bipolymer paclitaxel-nanoparticle using tea polysaccharide (TPS) and zein was prepared and characterized. Tea polysaccharide was used as a biopolymer shell and zein was as the core and the optimal formula was subjected to the characteristic study by TEM, DSC, FTIR and in vitro release study. Results showed that the optimal particle was acquired with particle yield at 40.01%, drug loading at 0.12% and diameters around 165nm when the concentration of tea polysaccharide was set at 0.2%, and the amount of PTX:zein=1:10. The particle was a nanoparticle with spherical surface and the encapsulated PTX was in an amorphous form rather than cystalline form. PTX was interacted with zein and polysaccharide through O H and CO groups and it had a sustained release. The results suggested that the novel bipolymer might be a promising agent for PTX delivery and tea polysaccharide was demonstrated its function in drug delivery system. Copyright © 2016 Elsevier Ltd. All rights reserved.

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.

[Effects of ammonium sulfate on the metabolism and K-feldspar weathering of two potassium-bearing mineral-solubilizing bacteria].

PubMed

Huang, Zhi; Ma, Guangyou; He, Linyan; Sheng, Xiafang

2012-02-04

To determine the best conditions for Bacillus globisporus Q12 and Rhizobium sp. Q32 to produce organic acids and extracellular polysaccharides, respectively, and further elucidate the weathering mechanism of the two potassium-bearing mineral-solubilizing bacteria. Different contents (0-1.2 g/L) of (NH4)2SO4 were added to media to analyze the ability of the strains to produce organic acids and extracellular polysaccharides, and assess the ability of Q12, Q32 and their mixture to dissolve potassium feldspar. Scanning electron microscope (SEM) was also used to observe the distribution of the bacterial cells on the surfaces of the feldspar and the mineral weathering. Results show that Bacillus globisporus Q12 produced more organic acids, when the contents of (NH4)2SO4 were 0.6 g/L; Rhizobium sp. Q32 produced more extracellular polysaccharides, when there was no (NH4)2SO4 in the media; and the mixture of two strains produced more organic acids and extracellular polysaccharides, when the contents of (NH4)2SO4 were 0.3 g/L. Mineral dissolution experiment showed that Bacillus globisporus Q12, Rhizobium sp. Q32 and the mixture (Q12 + Q32) significantly dissolved the feldspar and released the elements from the mineral, of which the mixture of Q12 and Q32 had the best weathering ability than strain Q12 or Q32; SEM also indicated that the mixture of Q12 and Q32 had more ability to weather feldspar than each tested strain. The contents of (NH4)2SO4 in the media could affect the growth and metabolites of the strains Q12 and Q32 and the mineral bioweathering, the mixture of strains Q12 and Q32 had the more potential of feldspar weathering through the combined action of organic acids and extracellular polysaccharides produced by strains Q12 and Q32.

Polysaccharide purified from Ganoderma atrum induced activation and maturation of murine myeloid-derived dendritic cells.

PubMed

Wang, Hui; Yu, Qiang; Nie, Shao-Ping; Xiang, Quan-Dan; Zhao, Ming-Ming; Liu, Shi-Yu; Xie, Ming-Yong; Wang, Shun-Qi

2017-10-01

Ganoderma atrum (G. atrum), a member of the genus Ganoderma, is an edible and medicinal fungus. In this study, we investigated the direct and indirect effects of G. atrum polysaccharide (PSG-1) on dendritic cells (DCs). Firstly, flow cytometric and ELISA analysis showed that PSG-1 increased cell surface molecule expression of MHC-II, CD80 and CD86, and enhanced the production of IL-12 p70, IL-6, IL-10, RANTES, MIP-1α and MCP-1 in DCs. PSG-1-treated DCs promoted the proliferation of splenic T lymphocyte of mouse in mixed lymphocyte reaction. The above results demonstrated that PSG-1 induced the maturation of DCs. Secondly, PSG-1 increased the phosphorylation of p38, ERK and JNK determined by western blot. Inhibitors of p38, ERK and JNK decreased PSG-1-induced expression of MHC-II, CD80 and CD86 and production of IL-6 and IL-10 by DCs. These results suggested that PSG-1 induced mitogen-activated protein kinase (MAPK) activation was involved in the regulation of maturation markers and cytokines expression in DCs. Finally, PSG-1 increased expression of MHC-II of DCs in a DCs-Caco-2 co-culture model, suggesting that PSG-1 could indirectly influence DCs. In summary, our data suggested that PSG-1 directly induced DCs maturation via activating MAPK pathways, and indirectly stimulated DCs separated by intestinal epithelial cells. Copyright © 2017. Published by Elsevier Ltd.

Drag reduction by Acinetobacter calcoaceticus BD4.

PubMed

Sar, N; Rosenberg, E

1987-09-01

The encapsulated bacterium Acinetobacter calcoaceticus BD4 at a density of 3.6 X 10(9) cells per ml reduced the friction of turbulent water in a narrow pipe by 55%. This drag reduction was due to the tightly bound polysaccharide capsules (0.4 mg per ml) of culture. Capsule-deficient mutants of BD4 failed to reduce drag. The cell-bound polysaccharide demonstrated a threefold-higher drag-reducing activity than the polymer which was free in solution.

Genome-wide transcriptional profiling of Botrytis cinerea genes targeting plant cell walls during infections of different hosts

PubMed Central

Blanco-Ulate, Barbara; Morales-Cruz, Abraham; Amrine, Katherine C. H.; Labavitch, John M.; Powell, Ann L. T.; Cantu, Dario

2014-01-01

Cell walls are barriers that impair colonization of host tissues, but also are important reservoirs of energy-rich sugars. Growing hyphae of necrotrophic fungal pathogens, such as Botrytis cinerea (Botrytis, henceforth), secrete enzymes that disassemble cell wall polysaccharides. In this work we describe the annotation of 275 putative secreted Carbohydrate-Active enZymes (CAZymes) identified in the Botrytis B05.10 genome. Using RNAseq we determined which Botrytis CAZymes were expressed during infections of lettuce leaves, ripe tomato fruit, and grape berries. On the three hosts, Botrytis expressed a common group of 229 potentially secreted CAZymes, including 28 pectin backbone-modifying enzymes, 21 hemicellulose-modifying proteins, 18 enzymes that might target pectin and hemicellulose side-branches, and 16 enzymes predicted to degrade cellulose. The diversity of the Botrytis CAZymes may be partly responsible for its wide host range. Thirty-six candidate CAZymes with secretion signals were found exclusively when Botrytis interacted with ripe tomato fruit and grape berries. Pectin polysaccharides are notably abundant in grape and tomato cell walls, but lettuce leaf walls have less pectin and are richer in hemicelluloses and cellulose. The results of this study not only suggest that Botrytis targets similar wall polysaccharide networks on fruit and leaves, but also that it may selectively attack host wall polysaccharide substrates depending on the host tissue. PMID:25232357

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 and testing of a Haemophilus influenzae Type b/Hepatitis B surface antigen conjugate vaccine.

PubMed

An, So Jung; Woo, Joo Sung; Chae, Myung Hwa; Kothari, Sudeep; Carbis, Rodney

2015-03-24

The majority of conjugate vaccines focus on inducing an antibody response to the polysaccharide antigen and the carrier protein is present primarily to induce a T-cell dependent response. In this study conjugates consisting of poly(ribosylribitolphosphate) (PRP) purified from Haemophilus influenzae Type b bound to Hepatitis B virus surface antigen (HBsAg) virus like particles were prepared with the aim of inducing an antibody response to not only the PRP but also the HBsAg. A conjugate consisting of PRP bound to HBsAg via an adipic acid dihydrazide (ADH) spacer induced strong IgG antibodies to both the PRP and HBsAg. When conjugation was performed without the ADH spacer the induction of an anti-PRP response was equivalent to that seen by conjugate with the ADH spacer, however, a negligible anti-HBsAg response was induced. For comparison, PRP was conjugated to diphtheria toxoid (DT) and Vi polysaccharide purified from Salmonella Typhi conjugated to HBsAg both using an ADH spacer. The PRPAH-DT conjugate induced strong anti-PRP and anti-DT responses, the Vi-AHHBsAg conjugate induced a good anti-HBsAg response but not as strong as that induced by the PRPAH-HBsAg conjugate. This study demonstrated that in mice it was possible to induce robust antibody responses to both polysaccharide and carrier protein provided the conjugate has certain physico-chemical properties. A PRPAH-HBsAg conjugate with the capacity to induce anti-PRP and anti-HBsAg responses could be incorporated into a multivalent pediatric vaccine and simplify formulation of such a vaccine. Copyright © 2015 Elsevier Ltd. All rights reserved.

Analysis of compounds that interfere with herpes simplex virus-host receptor interactions using surface plasmon resonance.

PubMed

Gopinath, Subash C B; Hayashi, Kyoko; Lee, Jung-Bum; Kamori, Akiko; Dong, Cai-Xia; Hayashi, Toshimitsu; Kumar, Penmetcha K R

2013-11-05

The entry of herpes simplex virus into host cells involves a complex series of events that require concerted inputs from multiple HSV glycoproteins. Among these glycoproteins, the gD protein of HSV-1 and HSV-2 plays an important role for host receptor binding and membrane fusion. In the present study, we evaluated the ability of different sulfated saccharides to interfere with gD-host receptor (HVEM) interactions using our recently reported molecular assay (Gopinath, S. C. B.; Hayashi, K.; Kumar, P. K. R. J. Virol. 2012, 86, 6732-6744). Initially, we tested the ability of heparan sulfate to interfere with the HVEM-HSV-1 gD interaction and found that heparan sulfate is able to interfere efficiently, with an apparent EC50 of 2.1 μM. In addition, we tested different synthetic sulfated polysaccharides and natural sulfated polysaccharides from an edible alga, Sargassum horneri , after fractionation into different sizes and sulfate and uronic acid contents. Six polysaccharides isolated from S. horneri were found to efficiently interfere with the HVEM-gD interaction. Three others caused moderate interference, and five caused weak interference. These results were confirmed with plaque assays, and good agreement was found with the results of the SPR assay for the identification of compounds that interfere with HVEM-HSV-1 gD binding. These studies suggest that our molecular assay based on surface plasmon resonance is not only useful for the analysis of viral-host protein interactions but is also applicable for the routine screening of compounds to identify those that interfere with the first step of viral entry, thus facilitating the rapid development of novel antiviral compounds that target HSV.

Physicochemical properties of water-soluble polysaccharides from black cumin seeds.

PubMed

Trigui, Ines; Yaich, Héla; Sila, Assaâd; Cheikh-Rouhou, Salma; Bougatef, Ali; Blecker, Christophe; Attia, Hamadi; Ayadi, M A

2018-06-01

In the present work, water-soluble polysaccharides were isolated from black cumin seeds. Polysaccharides were characterized by their carbohydrate composition, molecular weight, thermal stability and by FTIR, NMR spectroscopy and X-ray diffraction. The surface, the functional and the antioxidant properties of black cumin water-soluble polysaccharides (BCWSP) were also investigated. BCWSP consisted mainly of galacturonic acid (30.20%), glucuronic acid (17.66%) and neutral sugar (22.99%). BCWSP was composed of high peak molecular weight. The FTIR spectrum obtained for BCWSP showed two most important absorptions, at 1659 and 1085 cm -1 , which corresponded to COO - of uronic acids and pyranose form, respectively. NMR spectroscopy data suggested that the BCWSP is probably a rhamnogalacturonan backbone with galactan and arabinan side chains. X-ray pattern revealed the semi-crystalline behavior of BCWSP. WHC and OHC of BCWSP were relatively high and varied with temperatures. The polysaccharide zeta potential was greatly affected by pH. Results indicated that the decrease of surface tension has influenced foaming and emulsifying capacities. The DPPH radical scavenging activity of the BCWSP was 63.25% at 1 mg/mL. The BCWSP displayed moderate reductive, β carotene bleaching and chelating abilities. Overall, our results suggested that BCWSP could be used as alternative additives in food and non-food products. Copyright © 2017. Published by Elsevier B.V.

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.

Characterization of cell surface and extracellular matrix remodeling of Azospirillum brasilense chemotaxis-like 1 signal transduction pathway mutants by atomic force microscopy.

PubMed

Edwards, Amanda Nicole; Siuti, Piro; Bible, Amber N; Alexandre, Gladys; Retterer, Scott T; Doktycz, Mitchel J; Morrell-Falvey, Jennifer L

2011-01-01

To compete in complex microbial communities, bacteria must sense environmental changes and adjust cellular functions for optimal growth. Chemotaxis-like signal transduction pathways are implicated in the regulation of multiple behaviors in response to changes in the environment, including motility patterns, exopolysaccharide production, and cell-to-cell interactions. In Azospirillum brasilense, cell surface properties, including exopolysaccharide production, are thought to play a direct role in promoting flocculation. Recently, the Che1 chemotaxis-like pathway from A. brasilense was shown to modulate flocculation, suggesting an associated modulation of cell surface properties. Using atomic force microscopy, distinct changes in the surface morphology of flocculating A. brasilense Che1 mutant strains were detected. Whereas the wild-type strain produces a smooth mucosal extracellular matrix after 24 h, the flocculating Che1 mutant strains produce distinctive extracellular fibril structures. Further analyses using flocculation inhibition, lectin-binding assays, and comparison of lipopolysaccharides profiles suggest that the extracellular matrix differs between the cheA1 and the cheY1 mutants, despite an apparent similarity in the macroscopic floc structures. Collectively, these data indicate that disruption of the Che1 pathway is correlated with distinctive changes in the extracellular matrix, which likely result from changes in surface polysaccharides structure and/or composition. FEMS Microbiology Letters © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. No claim to original US government works.

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

Microanalysis of plant cell wall polysaccharides.

PubMed

Obel, Nicolai; Erben, Veronika; Schwarz, Tatjana; Kühnel, Stefan; Fodor, Andrea; Pauly, Markus

2009-09-01

Oligosaccharide Mass Profiling (OLIMP) allows a fast and sensitive assessment of cell wall polymer structure when coupled with Matrix Assisted Laser Desorption Ionisation Time Of Flight Mass Spectrometry (MALDI-TOF MS). The short time required for sample preparation and analysis makes possible the study of a wide range of plant organs, revealing a high degree of heterogeneity in the substitution pattern of wall polymers such as the cross-linking glycan xyloglucan and the pectic polysaccharide homogalacturonan. The high sensitivity of MALDI-TOF allows the use of small amounts of samples, thus making it possible to investigate the wall structure of single cell types when material is collected by such methods as laser micro-dissection. As an example, the analysis of the xyloglucan structure in the leaf cell types outer epidermis layer, entire epidermis cell layer, palisade mesophyll cells, and vascular bundles were investigated. OLIMP is amenable to in situ wall analysis, where wall polymers are analyzed on unprepared plant tissue itself without first isolating cell walls. In addition, OLIMP enables analysis of wall polymers in Golgi-enriched fractions, the location of nascent matrix polysaccharide biosynthesis, enabling separation of the processes of wall biosynthesis versus post-deposition apoplastic metabolism. These new tools will make possible a semi-quantitative analysis of the cell wall at an unprecedented level.

Analysis of Marine Aerosol Polysaccharides by Pyrolysis Time-of-Flight Mass Spectrometry

NASA Astrophysics Data System (ADS)

Lawler, M. J.; Grieman, M. M.; Sengur, I.; Saltzman, E. S.

2017-12-01

The relationship between surface ocean biological productivity and marine cloud formation and properties has been explored for decades, but the impacts of marine biogenic emissions on cloudiness and climate remain highly uncertain. This is in part due to the challenge of directly linking biogenic materials in the surface ocean with cloud-forming aerosol. It has been shown that polysaccharide gel-forming materials, also known as transparent exopolymers, may be mechanically ejected from the sea surface during air bubble bursting (Leck and Bigg, 2005). Existing analysis methods for such aerosols require considerable sample mass and sample preparation. As part of the multi-year seasonal North Atlantic Aerosols and Marine Ecosystems Study (NAAMES), ambient submicron marine aerosol was collected in November 2015 and May 2016 from the R/V Atlantis at using a Particle into Liquid Sampler (PILS). These samples of roughly 15 minute time resolution were frozen and returned to UC Irvine for analysis. A new technique has been developed to attempt to quantify polysaccharide material in these ambient samples. A small subsample (1- 5 µL) is taken from the PILS vial samples and allowed to dry on a Pt ribbon filament in the chemical ionization source region of a time-of-flight mass spectrometer. The sample then undergoes a two-step heating process, in which volatilizable molecules are first desorbed and then non-volatilizable large molecules such as polysaccharides are pyrolyzed. These desorbed molecules and decomposition products are ionized using either O2- or H3O+ reagent ion and are directly sampled into the mass spectrometer. The resulting spectra can then be compared to standards of known polysaccharide materials for quantification and potentially structural and/or compositional information.

Wheatgrass-Derived Polysaccharide Has Antiinflammatory, Anti-Oxidative and Anti-Apoptotic Effects on LPS-Induced Hepatic Injury in Mice.

PubMed

Nepali, Sarmila; Ki, Hyeon-Hui; Lee, Ji-Hyun; Lee, Hoon-Yeon; Kim, Dae-Ki; Lee, Young-Mi

2017-07-01

Hepatic injury occurs frequently during sepsis, and polysaccharides isolated from plants have been reported to have antiinflammatory and antioxidant effects in various models. However, the effect of wheatgrass-derived polysaccharide (WGP) has not been previously studied. In the present study, we investigated the effect of WGP on lipopolysaccharide (LPS)-induced hepatic injury in mice. Mice were pre-treated with WGP (100 or 200 mg/kg daily for 2 days) and then challenged with LPS (1 mg/kg, intraperitoneal), and sacrificed after 12 h. Wheatgrass-derived polysaccharide decreased serum aminotransferase levels and histological changes as compared with LPS-challenged mice. Wheatgrass-derived polysaccharide also significantly inhibited LPS-induced pro-inflammatory cytokine up-regulation and improved the oxidative status of liver tissues. Furthermore, these effects were found to be mediated by the suppression of the transcriptional activity of nuclear factor-kappa B (NF-κB), due to inhibitions of transforming growth factor beta (TGF-β)-activated kinase (TAK)-1 phosphorylation and inhibition of kappa B (IκB)-α degradation. In addition, WGP inhibited the activations of mitogen-activated protein kinases (MAPKs). Wheatgrass-derived polysaccharide also attenuated hepatic cell death by modulating caspase-3 and apoptosis associated mitochondrial proteins, such as, B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax). Taken together, WGP possesses antiinflammatory, anti-oxidant and anti-apoptotic activity and ameliorates LPS-induced liver injury in mice. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

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.

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.

Crohn's disease-associated adherent-invasive Escherichia coli adhesion is enhanced by exposure to the ubiquitous dietary polysaccharide maltodextrin.

PubMed

Nickerson, Kourtney P; McDonald, Christine

2012-01-01

Crohn's disease (CD) is associated with intestinal dysbiosis evidenced by an altered microbiome forming thick biofilms on the epithelium. Additionally, adherent-invasive E. coli (AIEC) strains are frequently isolated from ileal lesions of CD patients indicating a potential role for these strains in disease pathogenesis. The composition and characteristics of the host microbiome are influenced by environmental factors, particularly diet. Polysaccharides added to food as emulsifiers, stabilizers or bulking agents have been linked to bacteria-associated intestinal disorders. The escalating consumption of polysaccharides in Western diets parallels an increased incidence of CD during the latter 20(th) century. In this study, the effect of a polysaccharide panel on adhesiveness of the CD-associated AIEC strain LF82 was analyzed to determine if these food additives promote disease-associated bacterial phenotypes. Maltodextrin (MDX), a polysaccharide derived from starch hydrolysis, markedly enhanced LF82 specific biofilm formation. Biofilm formation of multiple other E. coli strains was also promoted by MDX. MDX-induced E. coli biofilm formation was independent of polysaccharide chain length indicating a requirement for MDX metabolism. MDX exposure induced type I pili expression, which was required for MDX-enhanced biofilm formation. MDX also increased bacterial adhesion to human intestinal epithelial cell monolayers in a mechanism dependent on type 1 pili and independent of the cellular receptor CEACAM6, suggesting a novel mechanism of epithelial cell adhesion. Analysis of mucosa-associated bacteria from individuals with and without CD showed increased prevalence of malX, a gene essential for MDX metabolism, uniquely in the ileum of CD patients. These findings demonstrate that the ubiquitous dietary component MDX enhances E. coli adhesion and suggests a mechanism by which Western diets rich in specific polysaccharides may promote dysbiosis of gut microbes and contribute to disease susceptibility.

Polysaccharides as cell carriers for tissue engineering: the use of cellulose in vascular wall reconstruction.

PubMed

Bačáková, L; Novotná, K; Pařízek, M

2014-01-01

Polysaccharides are long carbohydrate molecules of monosaccharide units joined together by glycosidic bonds. These biological polymers have emerged as promising materials for tissue engineering due to their biocompatibility, mostly good availability and tailorable properties. This complex group of biomolecules can be classified using several criteria, such as chemical composition (homo- and heteropolysaccharides), structure (linear and branched), function in the organism (structural, storage and secreted polysaccharides), or source (animals, plants, microorganisms). Polysaccharides most widely used in tissue engineering include starch, cellulose, chitosan, pectins, alginate, agar, dextran, pullulan, gellan, xanthan and glycosaminoglycans. Polysaccharides have been applied for engineering and regeneration of practically all tissues, though mostly at the experimental level. Polysaccharides have been tested for engineering of blood vessels, myocardium, heart valves, bone, articular and tracheal cartilage, intervertebral discs, menisci, skin, liver, skeletal muscle, neural tissue, urinary bladder, and also for encapsulation and delivery of pancreatic islets and ovarian follicles. For these purposes, polysaccharides have been applied in various forms, such as injectable hydrogels or porous and fibrous scaffolds, and often in combination with other natural or synthetic polymers or inorganic nanoparticles. The immune response evoked by polysaccharides is usually mild, and can be reduced by purifying the material or by choosing appropriate crosslinking agents.

Polysaccharides and their depolymerized fragments from Costaria costata: Molecular weight and sulfation-dependent anticoagulant and FGF/FGFR signal activating activities.

PubMed

Hou, Ningning; Zhang, Meng; Xu, Yingjie; Sun, Zhongmin; Wang, Jing; Zhang, Lijuan; Zhang, Quanbin

2017-12-01

Crude polysaccharides from Costaria costata were extracted by hot water and further fractionated by anion exchange chromatography into three polysaccharide fractions. Three low molecular weight fragments were then prepared by degradation of the polysaccharides with hydrogen peroxide and ascorbic acid. The structural features of the polysaccharides and their low molecular weight fragments were elucidated for the first time based on the HGPC, FT-IR, NMR, MS, monosaccharide composition, and other chemical analyses. Their anticoagulant and FGF-1, -2, -7, -8, -9, -10/FGFR1c signaling activation activities in BaF3 cells were also examined. Our studies showed that the polysaccharides were sulfated at different positions of galactose and fucose residues. The APTT-, PT- and TT-based anticoagulant assay results indicated that a high molecular weight and a higher degree of sulfation were essential for their anticoagulant activities. In contrast, not only the polysaccharides but also the depolymerized fragments showed significant FGF/FGFR signal activating activities in a FGF-, molecular weight-, and sulfation-dependent manner. The results presented in current study demonstrated the potential use of the polysaccharides and their fragments as anticoagulants and FGF signal regulators. Copyright © 2017 Elsevier B.V. All rights reserved.

Search for the antiprostatic principle of stinging nettle (Urtica dioica) roots.

PubMed

Wagner, H; Willer, F; Samtleben, R; Boos, G

1994-12-01

While searching for the antiprostatic active principle of the roots of Urtica dioica we ethanol-precipitated a polysaccharide mixture from an aqueous root extract and obtained chemically defined acidic polysaccharides with molecular masses of 15-210kDa. The chemical structures of these compounds have been determined. Some polysaccharides stimulated T lymphocytes in vitro while others influenced the complement system or triggered the release of TNF-α. The crude polysaccharide extract showed a prolonged antiinflammatory activity in the rat paw edema test for 22 hr, which is comparable to the pharmacological efficacy of indometacin. We have reisolated the isolectin mixture (UDA) originally detected in Urtica roots by Peumans et al. (1984). This mixture displayed immunomodulatory effects on T lymphocytes in a dose-dependent manner. In addition, UDA also directly inhibited cell proliferation and blocked binding of epidermal growth factor to its receptor on a tumor cell line, as determined by a [(125)I]-EGF binding assay. These investigations suggest that Urtica polysaccharides and also the N-acetyl-glucosamine specific lectin UDA play a major role in the antiprostatic activity of the drug and phytopreparations containing it. Copyright © 1994 Gustav Fischer Verlag, Stuttgart · Jena · New York. Published by Elsevier GmbH.. All rights reserved.

Investigation of the Maillard Reaction between Polysaccharides and Proteins from Longan Pulp and the Improvement in Activities.

PubMed

Han, Miao-Miao; Yi, Yang; Wang, Hong-Xun; Huang, Fei

2017-06-05

The purpose of this study was to investigate the Maillard reaction between polysaccharides and proteins from longan pulp and the effects of reaction on their in vitro activities. The polysaccharide-protein mixtures of fresh longan pulp (LPPMs) were co-prepared by an alkali extraction-acid precipitation method. They were then dry-heated under controlled conditions for monitoring the characterization of the Maillard reaction by the measurement of the free amino group content, ultraviolet-visible spectrum, Fourier transform infrared spectrum and molecular weight distribution. All the physicochemical analyses indicated the development of the Maillard reaction between polysaccharides and proteins. The in vitro activity evaluation indicated that the Maillard reaction could effectively enhance the antioxidant, antitumor and immunostimulating activities of LPPMs. The enhancement of 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and ferric reducing antioxidant power displayed both a positive correlation with the reaction time ( p < 0.05). LPPMs dry-heated for three days obtained relatively strong inhibitory activity against HepG2 cells and SGC7901 cells, as well as strong immunostimulating effects on the nitric oxide production and tumor necrosis factor α secretion of macrophages. Maillard-type intermacromolecular interaction is suggested to be an effective and controllable method for improving the functional activities of polysaccharides and proteins from longan pulp.

Polysaccharide Nanoparticles for Efficient siRNA Targeting in Cancer Cells by Supramolecular pKa Shift

NASA Astrophysics Data System (ADS)

Zhang, Ying-Ming; Yang, Yang; Zhang, Yu-Hui; Liu, Yu

2016-07-01

Biomacromolecular pKa shifting is considered as one of the most ubiquitous processes in biochemical events, e.g., the enzyme-catalyzed reaction and protein conformational stabilization. In this paper, we report on the construction of biocompatible polysaccharide nanoparticle with targeting ability and lower toxicity by supramolecular pKa shift strategy. This was realized through a ternary assembly constructed by the dual host‒guest interactions of an adamantane-bis(diamine) conjugate (ADA) with cucurbit[6]uril (CB[6]) and a polysaccharide. The potential application of such biocompatible nanostructure was further implemented by the selective transportation of small interfering RNA (siRNA) in a controlled manner. It is demonstrated that the strong encapsulation of the ADA’s diammonium tail by CB[6] not only reduced the cytotoxicity of the nano-scaled vehicle but also dramatically enhanced cation density through an obvious positive macrocycle-induced pKa shift, which eventually facilitated the subsequent siRNA binding. With a targeted polysaccharide shell containing a cyclodextrin‒hyaluronic acid conjugate, macrocycle-incorporated siRNA polyplexes were specifically delivered into malignant human prostate PC-3 cells. The supramolecular polysaccharide nanoparticles, the formation of which was enabled and promoted by the complexation-assisted pKa shift, may be used as a versatile tool for controlled capture and release of biofunctional substrates.

The role of complement in the success of vaccination with conjugated vs. unconjugated polysaccharide antigen.

PubMed

Salehen, Nur'ain; Stover, Cordula

2008-01-24

The complement system, a well-characterised arm of the innate immune system, significantly influences the adaptive immune response via direct cell-cell interaction and maintenance of lymphoid organ architecture. Development of vaccines is a major advance in modern health care. In this review, we highlight the importance of the marginal zone in response to both, polysaccharide and conjugated vaccines, and discuss the relevance of complement herein, based on findings obtained from animal models with specific deletions of certain complement components and from vaccination reports of complement-deficient individuals. We conclude that both, intactness of the complement system and maturity of expression of its components, are relatively more important to aid in the immune response to polysaccharide vaccine than to conjugated vaccines.

Soluble soybean polysaccharide/TiO2 bionanocomposite film for food application.

PubMed

Salarbashi, Davoud; Tafaghodi, Mohsen; Bazzaz, Bibi Sedigheh Fazly

2018-04-15

In the current study, a set of biodegradable soybean polysaccharide (SSPS) nanocomposites containing different ratios of TiO 2 nanoparticles was characterized as new packaging system. X-ray diffraction (XRD) measurement showed that the crystalline structure of the TiO 2 nanoparticles remained intact in the polysaccharide matrix and the surface of nanocomposites containing 1-3% TiO 2 was observed morphologically uniform under scanning electron microscopy (SEM). Dynamic mechanical thermal analysis revealed that the magnitude of storage modulus was 3.62-fold higher in SPSS/TiO 2 nanocomposites containing 7 wt.% of TiO 2 than control SSPS indicating improvement in the physical properties of the film supposed to be utilized for food packaging. With respect to the concern over the safety of these nanocomposites, inductively coupled plasma-optical emission spectroscopy (ICP-OES) showed that no TiO 2 was detected in bread samples covered by SSPS/TiO 2 film and stored for 6 months. Similarly, the nanocomposite films only released a minuscule amount (21.05 ± 0.054 ppm) of TiO 2 in water. TiO 2 nanoparticles were found in the plasma membrane of epithelial cell line after long-term exposure (10-day) of these cells to large amounts of the free nanoparticles. SSPS/TiO 2 nanocomposites showed excellent antimicrobial activity against Staphylococcus aureus PTCC 1431 (ATCC 25923), while neither anti-cancerous nor pro-cancerous activity was observed for these nanocomposites denoting their neutrality with respect to cancer suppression or progression in gastrointestinal tract. In conclusion, SSPS/TiO 2 nanocomposites could be a promising packaging system for food industries' objective regarding their physical characteristics, low rate of Ti transition, and low health risk. Copyright © 2018 Elsevier Ltd. All rights reserved.

Structure and anticancer activity of sulfated O-polysaccharide from marine bacterium Cobetia litoralis KMM 3880(T).

PubMed

Kokoulin, Maxim S; Kuzmich, Alexandra S; Kalinovsky, Anatoly I; Tomshich, Svetlana V; Romanenko, Lyudmila A; Mikhailov, Valery V; Komandrova, Nadezhda A

2016-12-10

We presented the structure of the polysaccharide moiety and anticancer activity in vitro of the sulfated lipopolysaccharide isolated from the marine bacterium Cobetia litoralis KMM 3880(T). The structure of O-polysaccharide was investigated by chemical methods along with (1)H and (13)C NMR spectroscopy. The O-polysaccharide was built up of branched trisaccharide repeating units consist of D-glucose (D-Glcр), D-mannose (D-Manр) and sulfated 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo5S): →7-β-Kdoр4Ac5S-(2→4)-[β-d-Glcp-(1→2)-]-β-d-Manр6Ac-1→. We demonstrated that the lipopolysaccharide and О-deacetylated O-polysaccharide from Cobetia litoralis KMM 3880(T) inhibited a colony formation of human melanoma SK-MEL-28 and colorectal carcinoma HTC-116 cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

Food-Derived Antioxidant Polysaccharides and Their Pharmacological Potential in Neurodegenerative Diseases

PubMed Central

Li, Haifeng; Ding, Fei; Xiao, Lingyun; Shi, Ruona; Wang, Hongyu; Han, Wenjing

2017-01-01

Oxidative stress is known to impair architecture and function of cells, which may lead to various chronic diseases, and therefore therapeutic and nutritional interventions to reduce oxidative damages represent a viable strategy in the amelioration of oxidative stress-related disorders, including neurodegenerative diseases. Over the past decade, a variety of natural polysaccharides from functional and medicinal foods have attracted great interest due to their antioxidant functions such as scavenging free radicals and reducing oxidative damages. Interestingly, these antioxidant polysaccharides are also found to attenuate neuronal damages and alleviate cognitive and motor decline in a range of neurodegenerative models. It has recently been established that the neuroprotective mechanisms of polysaccharides are related to oxidative stress-related pathways, including mitochondrial function, antioxidant defense system and pathogenic protein aggregation. Here, we first summarize the current status of antioxidant function of food-derived polysaccharides and then attempt to appraise their anti-neurodegeneration activities. PMID:28753972

Effect of phosphorylation on antioxidant activities of pumpkin (Cucurbita pepo, Lady godiva) polysaccharide.

PubMed

Song, Yi; Ni, Yuanying; Hu, Xiaosong; Li, Quanhong

2015-11-01

Phosphorylated derivatives of pumpkin polysaccharide with different degree of substitution were synthesized using POCl3 and pyridine. Antioxidant activities and cytoprotective effects of unmodified polysaccharide and phosphorylated derivatives were investigated employing various in vitro systems. Results showed that high ratio of POCl3/pyridine could increase the degree of substitution and no remarkable degradation occurred in the phosphorylation process. Characteristic absorption of phosphorylation appeared both in the IR and (31)P NMR spectrum. The df values between 2.27 and 2.55 indicated the relatively expanded conformation of the phosphorylated derivatives. All the phosphorylated polysaccharides exhibited higher antioxidant activities. H2O2-induced oxidative damages on rat thymic lymphocyte were also prevented by the derivatives. In general, phosphorylation could improve the antioxidant activities of pumpkin polysaccharide both in vitro and in a cell system. Copyright © 2015 Elsevier B.V. All rights reserved.

[Mechanism of apoptosis of nasopharyngeal carcinoma cells induced by polysaccharides extracts from Hedyotic diffusa].

PubMed

Jing Yan; Kang Min; Liu Jin; Li Jingyu; Tang Anzhou

2015-04-01

To explore the proliferation inhibition and apoptosis of polysaccharides extracts from polysaccharides extracts from Hedyotic diffusa (PEHD) on Human Nasopharyngeal Carcinoma (NPC)cell line CNE2 cells in vitro. CNE2 cells treated with various concentrations of PEHD were detected by MTT assay at 24 h, 48 h, and 72 h. The apoptotic cells were analyzed by flow cytometry with Annexin V/PI staining. The expression levels of Bax, Bcl-2 and caspase-3 protein were examined by Western blotting method. The growth of CNE2 cells were suppressed after treatment with PEHD (P < 0.05), MTT assay showed that the highest cell inhibition rate reached to 76.5%, the inhibition in the doses from 2 to 6 mg/ml showed dose-and-time-dependent. The percent of apoptosis in 4 and 6 mg/ml PEHD treatment groups for 48 h were 31.32%, 46.28%, respectively, and significantly higher than that in control groups, 4.86% (P < 0.01). After the cells being treated with PEHD for 48 h, the expression of Bax and caspase-3 protein increased, and the expression of Bcl-2 protein decreased gradually. PEHD could inhibited the growth of CNE2 cells and was dose-and-time-dependent, the mechanism may involve induction of cell apoptosis, which was associated with the activation of Bax and caspase-3 protein and the down-regulation of Bcl-2 protein expression.

Biosynthetic control of molecular weight in the polymerization of the octasaccharide subunits of succinoglycan, a symbiotically important exopolysaccharide of Rhizobium meliloti

PubMed Central

González, Juan E.; Semino, Carlos E.; Wang, Lai-Xi; Castellano-Torres, Laura E.; Walker, Graham C.

1998-01-01

Succinoglycan, a symbiotically important exopolysaccharide of Rhizobium meliloti, is composed of polymerized octasaccharide subunits, each of which consists of one galactose and seven glucoses with succinyl, acetyl, and pyruvyl modifications. Production of specific low molecular weight forms of R. meliloti exported and surface polysaccharides, including succinoglycan, appears to be important for nodule invasion. In a previous study of the roles of the various exo gene products in succinoglycan biosynthesis, exoP, exoQ, and exoT mutants were found to synthesize undecaprenol-linked fully modified succinoglycan octasaccharide subunits, suggesting possible roles for their gene products in polymerization or transport. Using improved techniques for analyzing succinoglycan biosynthesis by these mutants, we have obtained evidence indicating that R. meliloti has genetically separable systems for the synthesis of high molecular weight succinoglycan and the synthesis of a specific class of low molecular weight oligosaccharides consisting of dimers and trimers of the octasaccharide subunit. Models to account for our unexpected findings are discussed. Possible roles for the ExoP, ExoQ, and ExoT proteins are compared and contrasted with roles that have been suggested on the basis of homologies to key proteins involved in the biosynthesis of O-antigens and of certain exported or capsular cell surface polysaccharides. PMID:9811825

[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.

Immunologic Memory Induced by a Glycoconjugate Vaccine in a Murine Adoptive Lymphocyte Transfer Model

PubMed Central

Guttormsen, Hilde-Kari; Wetzler, Lee M.; Finberg, Robert W.; Kasper, Dennis L.

1998-01-01

We have developed an adoptive cell transfer model in mice to study the ability of a glycoprotein conjugate vaccine to induce immunologic memory for the polysaccharide moiety. We used type III capsular polysaccharide from the clinically relevant pathogen group B streptococci conjugated to tetanus toxoid (GBSIII-TT) as our model vaccine. GBS are a major cause of neonatal infections in humans, and type-specific antibodies to the capsular polysaccharide protect against invasive disease. Adoptive transfer of splenocytes from mice immunized with the GBSIII-TT conjugate vaccine conferred anti-polysaccharide immunologic memory to naive recipient mice. The transfer of memory occurred in a dose-dependent manner. The observed anamnestic immune response was characterized by (i) more rapid kinetics, (ii) isotype switching from immunoglobulin M (IgM) to IgG, and (iii) 10-fold-higher levels of type III-specific IgG antibody than for the primary response in animals with cells transferred from placebo-immunized mice. The adoptive cell transfer model described in this paper can be used for at least two purposes: (i) to evaluate conjugate vaccines with different physicochemical properties for their ability to induce immunologic memory and (ii) to study the cellular interactions required for an immune response to these molecules. PMID:9573085

Optimization of enzyme-assisted extraction and characterization of polysaccharides from Hericium erinaceus.

PubMed

Zhu, Yang; Li, Qian; Mao, Guanghua; Zou, Ye; Feng, Weiwei; Zheng, Daheng; Wang, Wei; Zhou, Lulu; Zhang, Tianxiu; Yang, Jun; Yang, Liuqing; Wu, Xiangyang

2014-01-30

The enzyme-assisted extraction (EAE) of polysaccharides from the fruits of Hericium erinaceus was studied. In this study, response surface methodology and the Box-Behnken design based on single-factor and orthogonal experiments were applied to optimize the EAE conditions. The optimal extraction conditions were as follows: a pH of 5.71, a temperature of 52.03°C and a time of 33.79 min. The optimal extraction conditions resulted in the highest H. erinaceus polysaccharides (HEP) yield, with a value 13.46 ± 0.37%, which represented an increase of 67.72% compared to hot water extraction (HWE). The polysaccharides were characterized by FT-IR, SEM, CD, AFM, and GC. The results showed that HEP was composed of mannose, glucose, xylose, and galactose in a molar ratio of 15.16:5.55:4.21:1. The functional groups of the H. erinaceus polysaccharides extracted by HWE and EAE were fundamentally identical but had apparent conformational changes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Changes in Cell Wall Polysaccharides Associated With Growth 1

PubMed Central

Nevins, Donald J.; English, Patricia D.; Albersheim, Peter

1968-01-01

Changes in the polysaccharide composition of Phaseolus vulgaris, P. aureus, and Zea mays cell walls were studied during the first 28 days of seedling development using a gas chromatographic method for the analysis of neutral sugars. Acid hydrolysis of cell wall material from young tissues liberates rhamnose, fucose, arabinose, xylose, mannose, galactose, and glucose which collectively can account for as much as 70% of the dry weight of the wall. Mature walls in fully expanded tissues of these same plants contain less of these constituents (10%-20% of dry wt). Gross differences are observed between developmental patterns of the cell wall in the various parts of a seedling, such as root, stem, and leaf. The general patterns of wall polysaccharide composition change, however, are similar for analogous organs among the varieties of a species. Small but significant differences in the rates of change in sugar composition were detected between varieties of the same species which exhibited different growth patterns. The cell walls of species which are further removed phylogenetically exhibit even more dissimilar developmental patterns. The results demonstrate the dynamic nature of the cell wall during growth as well as the quantitative and qualitative exactness with which the biosynthesis of plant cell walls is regulated. PMID:16656862

Effects of Bauhinia championii (Benth.) Benth. polysaccharides on the proliferation and cell cycle of chondrocytes.

PubMed

Cai, Liangliang; Ye, Hongzhi; Yu, Fangrong; Li, Huiting; Chen, Jiashou; Liu, Xianxiang

2013-05-01

It has been recently shown that polysaccharides isolated from plants exhibit a number of beneficial therapeutic properties. Bauhinia championii (Benth.) Benth. has been widely used for the clinical treatment of knee osteoarthritis (OA) in China. However, the underlying molecular mechanisms of knee OA treatment have yet to be elucidated. In the present study, we investigated the effects of Bauhinia championii (Benth.) Benth. polysaccharides (BCBPs) on the proliferation and cell cycle of chondrocytes on 4-week-old male Sprague Dawley rats. Immunohistochemical staining was used to identify chondrocytes and an MTT assay was used to evaluate cell viability. Flow cytometry was used for cell cycle analysis. The mRNA and protein expression levels of cyclin D1, CDK4 and CDK6 in chondrocytes were detected using reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis, respectively. The data demonstrate that BCBP treatment increased the viability of chondrocytes. In addition, BCBP treatment reduced the cell population in the G0/G1 phase, whereas the cell population was increased in the S phase. Furthermore, BCBP treatment enhanced the expression of cyclin D1, CDK4 and CDK6. These results indicate that BCBP treatment promotes cell proliferation by accelerating the G1/S transition.

Role of polysaccharides in food, digestion, and health

PubMed Central

Lovegrove, A.; Edwards, C. H.; De Noni, I.; Patel, H.; El, S. N.; Grassby, T.; Zielke, C.; Ulmius, M.; Nilsson, L.; Butterworth, P. J.; Ellis, P. R; Shewry, P. R.

2017-01-01

ABSTRACT Polysaccharides derived from plant foods are major components of the human diet, with limited contributions of related components from fungal and algal sources. In particular, starch and other storage carbohydrates are the major sources of energy in all diets, while cell wall polysaccharides are the major components of dietary fiber. We review the role of these components in the human diet, including their structure and distribution, their modification during food processing and effects on functional properties, their behavior in the gastrointestinal tract, and their contribution to healthy diets. PMID:25921546

[Antivirus effect of polysaccharides of brewer yeast in vitro].

PubMed

Li, F; Shi, Y; Guan, X; Zhang, S; Tian, T

1998-03-01

The antivirus effect of polysaccharides of brewer yeast from yeast mud on 13 kinds of viruses including DNA and RNA virus along with their mechanisms were studied. The result showed that this effect was remarkable on the infections with poliovirus III, adenovirus III, ECHO6 virus, enterovirus 71, vesicular stomatitis virus, herpesvirus I, II, coxsackie A16 virus and coxsackie B3 virus. The polysaccharides of brewer yeast could also inhibit the development of cytopathic effect(CPE) and protect cultural cells from being infected with the above viruses.

Role of polysaccharides in food, digestion, and health.

PubMed

Lovegrove, A; Edwards, C H; De Noni, I; Patel, H; El, S N; Grassby, T; Zielke, C; Ulmius, M; Nilsson, L; Butterworth, P J; Ellis, P R; Shewry, P R

2017-01-22

Polysaccharides derived from plant foods are major components of the human diet, with limited contributions of related components from fungal and algal sources. In particular, starch and other storage carbohydrates are the major sources of energy in all diets, while cell wall polysaccharides are the major components of dietary fiber. We review the role of these components in the human diet, including their structure and distribution, their modification during food processing and effects on functional properties, their behavior in the gastrointestinal tract, and their contribution to healthy diets.

Effect of a polysaccharide from Poria cocos on humoral response in mice immunized by H1N1 influenza and HBsAg vaccines.

PubMed

Wu, Yajun; Li, Shuai; Li, Haixia; Zhao, Chunzhi; Ma, Hao; Zhao, Xiunan; Wu, Junhua; Liu, Kunlu; Shan, Junjie; Wang, Yuxia

2016-10-01

Poria cocos has a long history of medicinal use in China. Polysaccharides and their derivatives in the medicine exhibit many beneficial biological activities including anticancer, anti-inflammatory, antioxidant and antiviral activities. In this study, a new polysaccharide (PCP-II) was isolated from sclerotium of Poria cocos. Its physico-chemical characters were identified and its adjuvant activity was investigated in mice co-immunized with H1N1 influenza vaccine and hepatitis B surface antigen (HBsAg). The results revealed that PCP-II has a molecular weight of 29.0kDa. It was composed of fucose, mannose, glucose and galactose in molar ration of 1.00:1.63:0.16:6.29 respectively. Pharmacological data demonstrated that PCP-II increased antigen-specific antibody levels in mice immunized with influenza vaccine. PCP-II also elicited anti-HBsAg antibodies at significantly higher titers and generated robust and durable immunity compared to mice immunized with HBsAg-alum following two administrations. PCP-II improved proliferation of splenocytes, stimulated IL-12p70 and TNF-α productions in dendritic cells and macrophages respectively. These results suggested that PCP-II-adjuvanted vaccines enhanced humoral and cellular immunity. PCP-II could be developed as an efficacious adjuvant in human and animal vaccines. Copyright © 2016 Elsevier B.V. All rights reserved.

Structural and biochemical changes induced by pulsed electric field treatments on Cabernet Sauvignon grape berry skins: impact on cell wall total tannins and polysaccharides.

PubMed

Cholet, Céline; Delsart, Cristèle; Petrel, Mélina; Gontier, Etienne; Grimi, Nabil; L'hyvernay, Annie; Ghidossi, Remy; Vorobiev, Eugène; Mietton-Peuchot, Martine; Gény, Laurence

2014-04-02

Pulsed electric field (PEF) treatment is an emerging technology that is arousing increasing interest in vinification processes for its ability to enhance polyphenol extraction performance. The aim of this study was to investigate the effects of PEF treatment on grape skin histocytological structures and on the organization of skin cell wall polysaccharides and tannins, which, until now, have been little investigated. This study relates to the effects of two PEF treatments on harvested Cabernet Sauvignon berries: PEF1 (medium strength (4 kV/cm); short duration (1 ms)) and PEF2 (low intensity (0.7 kV/cm); longer duration (200 ms)). Histocytological observations and the study of levels of polysaccharidic fractions and total amounts of tannins allowed differentiation between the two treatments. Whereas PEF1 had little effect on the polyphenol structure and pectic fraction, PEF2 profoundly modified the organization of skin cell walls. Depending on the PEF parameters, cell wall structure was differently affected, providing variable performance in terms of polyphenol extraction and wine quality.

Developmentally-Regulated Excision of the SPβ Prophage Reconstitutes a Gene Required for Spore Envelope Maturation in Bacillus subtilis

PubMed Central

Abe, Kimihiro; Kawano, Yuta; Iwamoto, Keito; Arai, Kenji; Maruyama, Yuki; Eichenberger, Patrick; Sato, Tsutomu

2014-01-01

Temperate phages infect bacteria by injecting their DNA into bacterial cells, where it becomes incorporated into the host genome as a prophage. In the genome of Bacillus subtilis 168, an active prophage, SPβ, is inserted into a polysaccharide synthesis gene, spsM. Here, we show that a rearrangement occurs during sporulation to reconstitute a functional composite spsM gene by precise excision of SPβ from the chromosome. SPβ excision requires a putative site-specific recombinase, SprA, and an accessory protein, SprB. A minimized SPβ, where all the SPβ genes were deleted, except sprA and sprB, retained the SPβ excision activity during sporulation, demonstrating that sprA and sprB are necessary and sufficient for the excision. While expression of sprA was observed during vegetative growth, sprB was induced during sporulation and upon mitomycin C treatment, which triggers the phage lytic cycle. We also demonstrated that overexpression of sprB (but not of sprA) resulted in SPβ prophage excision without triggering the lytic cycle. These results suggest that sprB is the factor that controls the timing of phage excision. Furthermore, we provide evidence that spsM is essential for the addition of polysaccharides to the spore envelope. The presence of polysaccharides on the spore surface renders the spore hydrophilic in water. This property may be beneficial in allowing spores to disperse in natural environments via water flow. A similar rearrangement occurs in Bacillus amyloliquefaciens FZB42, where a SPβ-like element is excised during sporulation to reconstitute a polysaccharide synthesis gene, suggesting that this type of gene rearrangement is common in spore-forming bacteria because it can be spread by phage infection. PMID:25299644

Genetic basis of coaggregation receptor polysaccharide biosynthesis in Streptococcus sanguinis and related species.

PubMed

Yang, J; Yoshida, Y; Cisar, J O

2014-02-01

Interbacterial adhesion between streptococci and actinomyces promotes early dental plaque biofilm development. Recognition of coaggregation receptor polysaccharides (RPS) on strains of Streptococcus sanguinis, Streptococcus gordonii and Streptococcus oralis by Actinomyces spp. type 2 fimbriae is the principal mechanism of these interactions. Previous studies of genetic loci for synthesis of RPS (rps) and RPS precursors (rml, galE1 and galE2) in S. gordonii 38 and S. oralis 34 revealed differences between these strains. To determine whether these differences are strain-specific or species-specific, we identified and compared loci for polysaccharide biosynthesis in additional strains of these species and in several strains of the previously unstudied species, S. sanguinis. Genes for synthesis of RPS precursors distinguished the rps loci of different streptococci. Hence, rml genes for synthesis of TDP-L-Rha were in rps loci of S. oralis strains but at other loci in S. gordonii and S. sanguinis. Genes for two distinct galactose epimerases were also distributed differently. Hence, galE1 for epimerization of UDP-Glc and UDP-Gal was in galactose operons of S. gordonii and S. sanguinis strains but surprisingly, this gene was not present in S. oralis. Moreover, galE2 for epimerization of both UDP-Glc and UDP-Gal and UDP-GlcNAc and UDP-GalNAc was at a different locus in each species, including rps operons of S. sanguinis. The findings provide insight into cell surface properties that distinguish different RPS-producing streptococci and open an approach for identifying these bacteria based on the arrangement of genes for synthesis of polysaccharide precursors. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

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 inverted repeat (77bpIR) element near the 5' end. Here, we report on the identification of an antisense RNA (asRNA) encoded within the 77bpIR. We show that overexpression of this asRNA or deletion of the element decreases the amount of capsule. LPS structures were also altered by deletion of the 77bpIR, and reactivity to monoclonal antibodies to both O-LPS and A-LPS was eliminated. Our data indicate that the 77bpIR element is involved in modulating both LPS and capsule synthesis in P. gingivalis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

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), encompassing a 77-bp inverted repeat (77bpIR) element near the 5′ end. Here, we report on the identification of an antisense RNA (asRNA) encoded within the 77bpIR. We show that overexpression of this asRNA or deletion of the element decreases the amount of capsule. LPS structures were also altered by deletion of the 77bpIR, and reactivity to monoclonal antibodies to both O-LPS and A-LPS was eliminated. Our data indicate that the 77bpIR element is involved in modulating both LPS and capsule synthesis in P. gingivalis. PMID:25622614

Preparation of Lentinula edodes polysaccharide-calcium complex and its immunoactivity.

PubMed

Cui, Yujiao; Yan, Huidan; Zhang, Xuewu

2015-01-01

Polysaccharide is a major bioactive component of mushrooms. In this study, for the first time, starting from a new Lentinula edodes polysaccharide L2, we prepared a novel L2-calcium complex and the process was optimized. Scanning electron microscopy and Fourier Transform infrared spectrometry were used for characterization. The immunostimulating activities of L2 and L2-calcium complex were measured by enhancing the production of two cytokines TNF-α and IL-6 in RAW264.7 cells. While L2-calcium complex significantly stimulates the secretions of TNF-α and IL-6 compared with the control, complex with calcium ion decreased the secretion of them. These facts indicate that calcium ion can modulate immune stimulating activity of Lentinula edodes polysaccharide L2.

O-Acetylation of Plant Cell Wall Polysaccharides

PubMed Central

Gille, Sascha; Pauly, Markus

2011-01-01

Plant cell walls are composed of structurally diverse polymers, many of which are O-acetylated. How plants O-acetylate wall polymers and what its function is remained elusive until recently, when two protein families were identified in the model plant Arabidopsis that are involved in the O-acetylation of wall polysaccharides – the reduced wall acetylation (RWA) and the trichome birefringence-like (TBL) proteins. This review discusses the role of these two protein families in polysaccharide O-acetylation and outlines the differences and similarities of polymer acetylation mechanisms in plants, fungi, bacteria, and mammals. Members of the TBL protein family had been shown to impact pathogen resistance, freezing tolerance, and cellulose biosynthesis. The connection of TBLs to polysaccharide O-acetylation thus gives crucial leads into the biological function of wall polymer O-acetylation. From a biotechnological point understanding the O-acetylation mechanism is important as acetyl-substituents inhibit the enzymatic degradation of wall polymers and released acetate can be a potent inhibitor in microbial fermentations, thus impacting the economic viability of, e.g., lignocellulosic based biofuel production. PMID:22639638

Investigation of bacterial resistance to the immune system response: cepacian depolymerisation by reactive oxygen species.

PubMed

Cuzzi, Bruno; Cescutti, Paola; Furlanis, Linda; Lagatolla, Cristina; Sturiale, Luisa; Garozzo, Domenico; Rizzo, Roberto

2012-08-01

Reactive oxygen species (ROS) are part of the weapons used by the immune system to kill and degrade infecting microorganisms. Bacteria can produce macromolecules, such as polysaccharides, that are able to scavenge ROS. Species belonging to the Burkholderia cepacia complex are involved in serious lung infection in cystic fibrosis patients and produce a characteristic polysaccharide, cepacian. The interaction between ROS and bacterial polysaccharides was first investigated by killing experiments, where bacteria cells were incubated with sodium hypochlorite (NaClO) with and without prior incubation with cepacian. The results showed that the polysaccharide had a protective effect towards bacterial cells. Cepacian was then treated with different concentrations of NaClO and the course of reactions was followed by means of capillary viscometry. The degradation products were characterised by size-exclusion chromatography, NMR and mass spectrometry. The results showed that hypochlorite depolymerised cepacian, removed side chains and O-acetyl groups, but did not cleave the glycosidic bond between glucuronic acid and rhamnose. The structure of some oligomers produced by NaClO oxidation is reported.

Chemical characterization, antioxidant and antitumor activity of sulfated polysaccharide from Sargassum horneri.

PubMed

Shao, Ping; Chen, Xiaoxiao; Sun, Peilong

2014-05-25

Three water-soluble polysaccharide fractions (SHP30, SHP60, and SHP80) extracted from the Sargassum horneri were obtained by water extraction and radial flow chromatography. The high-performance gel-permeation chromatography analysis showed that the average molecular weight (Mw) of three polysaccharides were approximately 1.58×10(3), 1.92×10(3) and 11.2KDa, respectively. Their in vitro antioxidant activities, antitumor activities were investigated and compared. Among these three polysaccharides, SHP30 with the highest sulfate content and intermediate molecular weight exhibited excellent antioxidant and antitumor activities in the superoxide radical assay, hydroxyl radical assay, reducing power assay, and MTT assay. Then, flow cytometry assay and quantitative real-time reverse transcription-PCR analysis suggested that the accumulation of cells in G0/G1 and S phase effecting apoptosis-associated gene expressions such as Bcl-2 and Bax might account for the growth inhibition of DLD cells by SHP30. Based on these results, we have inferred that sulfate content and molecular weight were the factors influencing antioxidant and antitumor activities. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

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

Bacteriophage Tailspikes and Bacterial O-Antigens as a Model System to Study Weak-Affinity Protein-Polysaccharide Interactions.

PubMed

Kang, Yu; Gohlke, Ulrich; Engström, Olof; Hamark, Christoffer; Scheidt, Tom; Kunstmann, Sonja; Heinemann, Udo; Widmalm, Göran; Santer, Mark; Barbirz, Stefanie

2016-07-27

Understanding interactions of bacterial surface polysaccharides with receptor protein scaffolds is important for the development of antibiotic therapies. The corresponding protein recognition domains frequently form low-affinity complexes with polysaccharides that are difficult to address with experimental techniques due to the conformational flexibility of the polysaccharide. In this work, we studied the tailspike protein (TSP) of the bacteriophage Sf6. Sf6TSP binds and hydrolyzes the high-rhamnose, serotype Y O-antigen polysaccharide of the Gram-negative bacterium Shigella flexneri (S. flexneri) as a first step of bacteriophage infection. Spectroscopic analyses and enzymatic cleavage assays confirmed that Sf6TSP binds long stretches of this polysaccharide. Crystal structure analysis and saturation transfer difference (STD) NMR spectroscopy using an enhanced method to interpret the data permitted the detailed description of affinity contributions and flexibility in an Sf6TSP-octasaccharide complex. Dodecasaccharide fragments corresponding to three repeating units of the O-antigen in complex with Sf6TSP were studied computationally by molecular dynamics simulations. They showed that distortion away from the low-energy solution conformation found in the octasaccharide complex is necessary for ligand binding. This is in agreement with a weak-affinity functional polysaccharide-protein contact that facilitates correct placement and thus hydrolysis of the polysaccharide close to the catalytic residues. Our simulations stress that the flexibility of glycan epitopes together with a small number of specific protein contacts provide the driving force for Sf6TSP-polysaccharide complex formation in an overall weak-affinity interaction system.

Commensal Protection of Staphylococcus aureus against Antimicrobials by Candida albicans Biofilm Matrix.

PubMed

Kong, Eric F; Tsui, Christina; Kucharíková, Sona; Andes, David; Van Dijck, Patrick; Jabra-Rizk, Mary Ann

2016-10-11

Biofilm-associated polymicrobial infections, particularly those involving fungi and bacteria, are responsible for significant morbidity and mortality and tend to be challenging to treat. Candida albicans and Staphylococcus aureus specifically are considered leading opportunistic fungal and bacterial pathogens, respectively, mainly due to their ability to form biofilms on catheters and indwelling medical devices. However, the impact of mixed-species biofilm growth on therapy remains largely understudied. In this study, we investigated the influence of C. albicans secreted cell wall polysaccharides on the response of S. aureus to antibacterial agents in biofilm. Results demonstrated significantly enhanced tolerance for S. aureus to drugs in the presence of C. albicans or its secreted cell wall polysaccharide material. Fluorescence confocal time-lapse microscopy revealed impairment of drug diffusion through the mixed biofilm matrix. Using C. albicans mutant strains with modulated cell wall polysaccharide expression, exogenous supplementation, and enzymatic degradation, the C. albicans-secreted β-1,3-glucan cell wall component was identified as the key matrix constituent providing the bacteria with enhanced drug tolerance. Further, antibody labeling demonstrated rapid coating of the bacteria by the C. albicans matrix material. Importantly, via its effect on the fungal biofilm matrix, the antifungal caspofungin sensitized the bacteria to the drugs. Understanding such symbiotic interactions with clinical relevance between microbial species in biofilms will greatly aid in overcoming the limitations of current therapies and in defining potential new targets for treating polymicrobial infections. The fungus Candida albicans and the bacterium Staphylococcus aureus are important microbial pathogens responsible for the majority of infections in hospitalized patients and are often coisolated from a host. In this study, we demonstrated that when grown together, the fungus provides the bacterium with enhanced tolerance to antimicrobial drugs. This process was mediated by polysaccharides secreted by the fungal cell into the environment. The biofilm matrix formed by these polysaccharides prevented penetration by the drugs and provided the bacteria with protection. Importantly, we show that by inhibiting the production of the fungal polysaccharides, a specific antifungal agent indirectly sensitized the bacteria to antimicrobials. Understanding the therapeutic implications of the interactions between these two diverse microbial species will aid in overcoming the limitations of current therapies and in defining new targets for treating complex polymicrobial infections. Copyright © 2016 Kong et al.