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  1. Lectins with Anti-HIV Activity: A Review

    Directory of Open Access Journals (Sweden)

    Ouafae Akkouh

    2015-01-01

    Full Text Available Lectins including flowering plant lectins, algal lectins, cyanobacterial lectins, actinomycete lectin, worm lectins, and the nonpeptidic lectin mimics pradimicins and benanomicins, exhibit anti-HIV activity. The anti-HIV plant lectins include Artocarpus heterophyllus (jacalin lectin, concanavalin A, Galanthus nivalis (snowdrop agglutinin-related lectins, Musa acuminata (banana lectin, Myrianthus holstii lectin, Narcissus pseudonarcissus lectin, and Urtica diocia agglutinin. The anti-HIV algal lectins comprise Boodlea coacta lectin, Griffithsin, Oscillatoria agardhii agglutinin. The anti-HIV cyanobacterial lectins are cyanovirin-N, scytovirin, Microcystis viridis lectin, and microvirin. Actinohivin is an anti-HIV actinomycete lectin. The anti-HIV worm lectins include Chaetopterus variopedatus polychaete marine worm lectin, Serpula vermicularis sea worm lectin, and C-type lectin Mermaid from nematode (Laxus oneistus. The anti-HIV nonpeptidic lectin mimics comprise pradimicins and benanomicins. Their anti-HIV mechanisms are discussed.

  2. Characterization and antimicrobial activity of lectins from Penicillium sp.

    Science.gov (United States)

    Singh, R S; Jain, P; Kaur, H P

    2013-11-01

    Ten Penicillium sp. were screened for lectin activity for occurrence of lectins. Mycelial extracts from submerged cultures of P. corylophilum, P. expansum and P. purpurogenum showed agglutination against human (A, B, AB and O), goat, sheep, pig and rabbit erythrocytes. Neuraminidase treatment to human blood- type O erythrocytes substantially increased their agglutinability by all the lectins as compared to untreated erythrocytes. Modification of erythrocyte surfaces by protease increased the lectin titre only of P. corylophilum with no effect on other two lectins. P. corylophilum and P. expansum displayed relatively lower titres in mycelial extracts prepared from agar plate cultures as compared to broth cultures. A panel of sugars was tested for inhibition of lectin activity. All the lectins were found to be specific for asialofetuin, bovine submaxillary mucin, porcine stomach mucin, chondroitin-6-sulphate, D-sucrose and D-glucose. P. corylophilum lectin was expressed (Titre 8) by 5 day old cultures, reaching its maximum level (Titre 32) upon 8 days of cultivation, thereafter declin in lectin activity was observed. P. purpurogenum lectin was expressed by 7-10 days old cultures, while in P. expansum maximum lectin activity was elaborated by 5-8 days old cultures. Lectin extracts from all the three species were found to possess antimicrobial activities. Lectin extracts from the three Penicillium species displayed antifungal activity and antibacterial activity against Gram-negative and Gram-positive bacterial strains.

  3. Antifungal activity of lectins against yeast of vaginal secretion

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    Bruno Severo Gomes

    2012-06-01

    Full Text Available Lectins are carbohydrate-binding proteins of non-imune origin. This group of proteins is distributed widely in nature and they have been found in viruses, microorganisms, plants and animals. Lectins of plants have been isolated and characterized according to their chemical, physical-chemical, structural and biological properties. Among their biological activities, we can stress its fungicidal action. It has been previously described the effect of the lectins Dviol, DRL, ConBr and LSL obtained from the seeds of leguminous plants on the growth of yeasts isolated from vaginal secretions. In the present work the experiments were carried out in microtiter plates and the results interpreted by both methods: visual observations and a microplate reader at 530nm. The lectin concentrations varied from 0.5 to 256µg/mL, and the inoculum was established between 65-70% of trammitance. All yeast samples isolated from vaginal secretion were evaluated taxonomically, where were observed macroscopic and microscopic characteristics to each species. The LSL lectin did not demonstrate any antifungal activity to any isolate studied. The other lectins DRL, ConBr and DvioL, showed antifungal potential against yeast isolated from vaginal secretion. These findings offering offer a promising field of investigation to develop new therapeutic strategies against vaginal yeast infections, collaborating to improve women's health.

  4. Purification and characterization of a mucin specific mycelial lectin from Aspergillus gorakhpurensis: application for mitogenic and antimicrobial activity.

    Science.gov (United States)

    Singh, Ram Sarup; Kaur, Hemant Preet; Singh, Jatinder

    2014-01-01

    Lectins are carbohydrate binding proteins or glycoproteins that bind reversibly to specific carbohydrates present on the apposing cells, which are responsible for their ability to agglutinate red blood cells, lymphocytes, fibroblasts, etc. Interest in lectins has been intensified due to their carbohydrate specificity as they can be valuable reagents for the investigation of cell surface sugars, purification and characterization of glycoproteins. The present study reports the purification, characterization and evaluation of mitogenic and antimicrobial potential of a mycelial lectin from Aspergillus gorakhpurensis. Affinity chromatography on mucin-sepharose column was carried out for purification of Aspergillus gorakhpurensis lectin. The lectin was characterized for physico-chemical parameters. Mitogenic potential of the lectin was evaluated against splenocytes of Swiss albino mice by MTT assay. Antimicrobial activity of the purified lectin has also been evaluated by disc diffusion assay. Single-step affinity purification resulted in 18.6-fold purification of the mycelial lectin. The molecular mass of the lectin was found to be 70 kDa and it was composed of two subunits of 34.8 kDa as determined by gel filtration chromatography, SDS-PAGE and MALDI-TOF analysis. pH optima of the lectin was found to be 6.5-9.5, while optimum temperature for lectin activity was 20-30 °C. Lectin was stable within a pH range of 7.0-10.5 and showed fair thermostability. EDTA did not affect lectin activity whereas it was found susceptible to the denaturants tested. MTT assay revealed strong mitogenic potential of A. gorakhpurensis lectin at a concentration upto 150 µg/mL. Antimicrobial activity assay showed its potent antibacterial activity against Bacillus cereus, Staphylococcous aureus and Escherichia coli and marginal antifungal activity against Saccharomyces cerevisiae. This is the first report on the mitogenic and antimicrobial potential of Aspergillus gorakhpurensis lectin. The

  5. Antiviral lectins from red and blue-green algae show potent in vitro and in vivo activity against hepatitis C virus.

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    Yutaka Takebe

    Full Text Available Hepatitis C virus (HCV infection is a significant public health problem with over 170,000,000 chronic carriers and infection rates increasing worldwide. Chronic HCV infection is one of the leading causes of hepatocellular carcinoma which was estimated to result in ∼10,000 deaths in the United States in the year 2011. Current treatment options for HCV infection are limited to PEG-ylated interferon alpha (IFN-α, the nucleoside ribavirin and the recently approved HCV protease inhibitors telaprevir and boceprevir. Although showing significantly improved efficacy over the previous therapies, treatment with protease inhibitors has been shown to result in the rapid emergence of drug-resistant virus. Here we report the activity of two proteins, originally isolated from natural product extracts, which demonstrate low or sub-nanomolar in vitro activity against both genotype I and genotype II HCV. These proteins inhibit viral infectivity, binding to the HCV envelope glycoproteins E1 and E2 and block viral entry into human hepatocytes. In addition, we demonstrate that the most potent of these agents, the protein griffithsin, is readily bioavailable after subcutaneous injection and shows significant in vivo efficacy in reducing HCV viral titers in a mouse model system with engrafted human hepatocytes. These results indicate that HCV viral entry inhibitors can be an effective component of anti-HCV therapy and that these proteins should be studied further for their therapeutic potential.

  6. IDENTIFICATION OF LECTINS OF ZEA MAYS RAW MATERIAL AND THE STUDY OF LECTIN ACTIVITY

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    Karpiuk UV

    2013-03-01

    Full Text Available The aime of the study was to identify lectins in the Zea mays raw material: roots, stems, heads, leaves and corn silk and study their activity. Lectins activity has been studied using the biological method of ratuserytroagglutination. This method is based on formation of aggregates of lectins and rats erythrocytes. The activity unit was the floor amount of lectins that agglutinate erythrocytes. The protein nature of extracts that agglutinate has been determined using Bradford method. The lectins activity of Zea mays roots was 6,21±0,11 unit/mg of protein; of heads – 2,61±0,17 unit/mg of protein; of leaves – 0,62 ±0,05 unit/mg of protein; of corn silk – 1,06±0,08 unit/mg of protein; of stems – 0,97±0,09 unit/mg of protein. The greatest lectins activity was in leaves, stems and corn silk.

  7. Mitogenic activity of new lectins from seeds of wild Artocarpus species from Vietnam.

    Science.gov (United States)

    Blasco, E; Ngoc, L D; Aucouturier, P; Preud'Homme, J L; Barra, A

    1996-05-01

    Proliferative response of human peripheral blood mononuclear cells (PBMC) stimulated by new lectins purified from seeds of differents Artocarpus species from Vietnam (A. asperulus, A. heterophyllus, A. masticata, A. melinoxylus, A. parva and A. petelotii) was studied and compared to those of the lectin jacalin purified from jackfruit (A. heterophyllus) seeds collected in the island La Réunion. All lectins stimulated human PBMC to proliferate, with a variable efficiency of the mitogenic activity. Phenotypic analysis of cells recovered after 7 day-cultures showed that these lectins mostly stimulated CD4+ T lymphocytes. These results suggest that these lectins from different Artocarpus species are similar in terms of their mitogenic activity although their structural features are not identical.

  8. Activation of the lectin complement pathway on human renal ...

    African Journals Online (AJOL)

    This study aimed to investigate the roles of high glucose and mannose-binding lectin (MBL) on the activation of the lectin complement pathway (LCP) on human renal glomerular endothelial cells (HRGECs) in vitro. Flow cytometry analysis, immunofluorescence staining and Western blot were used to detect the cell surface ...

  9. Lectin activity in mycelial extracts of Fusarium species.

    Science.gov (United States)

    Bhari, Ranjeeta; Kaur, Bhawanpreet; Singh, Ram S

    2016-01-01

    Lectins are non-immunogenic carbohydrate-recognizing proteins that bind to glycoproteins, glycolipids, or polysaccharides with high affinity and exhibit remarkable ability to agglutinate erythrocytes and other cells. In the present study, ten Fusarium species previously not explored for lectins were screened for the presence of lectin activity. Mycelial extracts of F. fujikuroi, F. beomiformii, F. begoniae, F. nisikadoi, F. anthophilum, F. incarnatum, and F. tabacinum manifested agglutination of rabbit erythrocytes. Neuraminidase treatment of rabbit erythrocytes increased lectin titers of F. nisikadoi and F. tabacinum extracts, whereas the protease treatment resulted in a significant decline in agglutination by most of the lectins. Results of hapten inhibition studies demonstrated unique carbohydrate specificity of Fusarium lectins toward O-acetyl sialic acids. Activity of the majority of Fusarium lectins exhibited binding affinity to d-ribose, l-fucose, d-glucose, l-arabinose, d-mannitol, d-galactosamine hydrochloride, d-galacturonic acid, N-acetyl-d-galactosamine, N-acetyl-neuraminic acid, 2-deoxy-d-ribose, fetuin, asialofetuin, and bovine submaxillary mucin. Melibiose and N-glycolyl neuraminic acid did not inhibit the activity of any of the Fusarium lectins. Mycelial extracts of F. begoniae, F. nisikadoi, F. anthophilum, and F. incarnatum interacted with most of the carbohydrates tested. F. fujikuroi and F. anthophilum extracts displayed strong interaction with starch. The expression of lectin activity as a function of culture age was investigated. Most species displayed lectin activity on the 7th day of cultivation, and it varied with progressing of culture age. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  10. Characterization of chickpea (Cicer arietinum L.) lectin for biological activity.

    Science.gov (United States)

    Gautam, Ajay Kumar; Gupta, Neha; Narvekar, Dakshita T; Bhadkariya, Rajni; Bhagyawant, Sameer S

    2018-05-01

    Lectins are proteins that are subject of intense investigations. Information on lectin from chickpea ( Cicer arietinum L.) with respect to its biological activities are very limited. In this study, we purified lectin from the seeds of chickpea employing DEAE-cellulose and SP-Sephadex ion exchange chromatography and identified its molecular subunit mass as 35 kDa. The free radical scavenging activity of lectin measured by the DPPH assay has IC 50 of 0.88 µg/mL. Lectin exerted antifungal activity against Candida krusei , Fusarium oxysporium oxysporium , Saccharomyces cerevisiae and Candida albicans , while antibacterial activity against E. coli , B. subtilis , S. marcescens and P. aeruginosa. The minimum inhibitory concentrations were 200, 240, 160 and 140 µg for C. krusei, F. oxysporium , S. cerevisiae and C. albicans respectively. Lectin was further examined for its antiproliferative potential against cancerous cell line. The cell viability assay indicated a high inhibition activity on Ishikawa, HepG2, MCF-7 and MDA-MB-231 with IC 50 value of 46.67, 44.20, 53.58 and 37.46 µg/mL respectively. These results can provide a background for future research into the benefits of chickpea lectin to pharmacological perspective.

  11. Cholesterol Crystals Activate the Lectin Complement Pathway via Ficolin-2 and Mannose-Binding Lectin

    DEFF Research Database (Denmark)

    Pilely, Katrine; Rosbjerg, Anne; Genster, Ninette

    2016-01-01

    Cholesterol crystals (CC) play an essential role in the formation of atherosclerotic plaques. CC activate the classical and the alternative complement pathways, but the role of the lectin pathway is unknown. We hypothesized that the pattern recognition molecules (PRMs) from the lectin pathway bind...... CC and function as an upstream innate inflammatory signal in the pathophysiology of atherosclerosis. We investigated the binding of the PRMs mannose-binding lectin (MBL), ficolin-1, ficolin-2, and ficolin-3, the associated serine proteases, and complement activation products to CC in vitro using...... recognize CC and provides evidence for an important role for this pathway in the inflammatory response induced by CC in the pathophysiology of atherosclerosis....

  12. Narcissus tazetta lectin shows strong inhibitory effects against ...

    Indian Academy of Sciences (India)

    Prakash

    against human enveloped viruses (Balzarini 2007a). They ... NTL with a high selective index (SI=CC50/IC50 >141) resulting from its potent antiviral activity and low cytotoxicity demonstrates a potential for biotechnological development as an ...

  13. Two Chitotriose-Specific Lectins Show Anti-Angiogenesis, Induces Caspase-9-Mediated Apoptosis and Early Arrest of Pancreatic Tumor Cell Cycle.

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    Ruby Singh

    Full Text Available The antiproliferative activity of two chito-specific agglutinins purified from Benincasa hispida (BhL and Datura innoxia (DiL9 of different plant family origin was investigated on various cancer cell lines. Both lectins showed chitotriose specificity, by inhibiting lectin hemagglutinating activity. On further studies, it was revealed that these agglutinins caused remarkable concentration-dependent antiproliferative effect on human pancreatic cancerous cells but not on the normal human umbilical vein endothelial cells even at higher doses determined using MTT assay. The GI50 values were approximately 8.4 μg ml(-1 (0.247 μM and 142 μg ml(-1 (14.8 μM for BhL and DiL9, respectively, against PANC-1 cells. The growth inhibitory effect of these lectins on pancreatic cancer cells were shown to be a consequence of lectin cell surface binding and triggering G0/G1 arrest, mitochondrial membrane depolarization, sustained increase of the intracellular calcium release and the apoptotic signal is amplified by activation of caspases executing cell death. Interestingly, these lectins also showed anti-angiogenic activity by disrupting the endothelial tubulogenesis. Therefore, we report for the first time two chito-specific lectins specifically binding to tumor glycans; they can be considered to be a class of molecules with antitumor activity against pancreatic cancer cells mediated through caspase dependent mitochondrial apoptotic pathway.

  14. Insights into Animal and Plant Lectins with Antimicrobial Activities

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    Renata de Oliveira Dias

    2015-01-01

    Full Text Available Lectins are multivalent proteins with the ability to recognize and bind diverse carbohydrate structures. The glyco -binding and diverse molecular structures observed in these protein classes make them a large and heterogeneous group with a wide range of biological activities in microorganisms, animals and plants. Lectins from plants and animals are commonly used in direct defense against pathogens and in immune regulation. This review focuses on sources of animal and plant lectins, describing their functional classification and tridimensional structures, relating these properties with biotechnological purposes, including antimicrobial activities. In summary, this work focuses on structural-functional elucidation of diverse lectin groups, shedding some light on host-pathogen interactions; it also examines their emergence as biotechnological tools through gene manipulation and development of new drugs.

  15. Purification and characterization of a mucin specific mycelial lectin from Aspergillus gorakhpurensis: application for mitogenic and antimicrobial activity.

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    Ram Sarup Singh

    Full Text Available Lectins are carbohydrate binding proteins or glycoproteins that bind reversibly to specific carbohydrates present on the apposing cells, which are responsible for their ability to agglutinate red blood cells, lymphocytes, fibroblasts, etc. Interest in lectins has been intensified due to their carbohydrate specificity as they can be valuable reagents for the investigation of cell surface sugars, purification and characterization of glycoproteins. The present study reports the purification, characterization and evaluation of mitogenic and antimicrobial potential of a mycelial lectin from Aspergillus gorakhpurensis.Affinity chromatography on mucin-sepharose column was carried out for purification of Aspergillus gorakhpurensis lectin. The lectin was characterized for physico-chemical parameters. Mitogenic potential of the lectin was evaluated against splenocytes of Swiss albino mice by MTT assay. Antimicrobial activity of the purified lectin has also been evaluated by disc diffusion assay.Single-step affinity purification resulted in 18.6-fold purification of the mycelial lectin. The molecular mass of the lectin was found to be 70 kDa and it was composed of two subunits of 34.8 kDa as determined by gel filtration chromatography, SDS-PAGE and MALDI-TOF analysis. pH optima of the lectin was found to be 6.5-9.5, while optimum temperature for lectin activity was 20-30 °C. Lectin was stable within a pH range of 7.0-10.5 and showed fair thermostability. EDTA did not affect lectin activity whereas it was found susceptible to the denaturants tested. MTT assay revealed strong mitogenic potential of A. gorakhpurensis lectin at a concentration upto 150 µg/mL. Antimicrobial activity assay showed its potent antibacterial activity against Bacillus cereus, Staphylococcous aureus and Escherichia coli and marginal antifungal activity against Saccharomyces cerevisiae.This is the first report on the mitogenic and antimicrobial potential of Aspergillus gorakhpurensis

  16. Mannan-binding lectin activates C3 and the

    DEFF Research Database (Denmark)

    Selander, B.; Martensson, U.; Weintraub, A.

    2006-01-01

    Lectin pathway activation of C3 is known to involve target recognition by mannan-binding lectin (MBL) or ficolins and generation of classical pathway C3 convertase via cleavage of C4 and C2 by MBL-associated serine protease 2 (MASP-2). We investigated C3 activation in C2-deficient human sera...... and in sera with other defined defects of complement to assess other mechanisms through which MBL might recruit complement. The capacity of serum to support C3 deposition was examined by ELISA using microtiter plates coated with O antigen-specific oligosaccharides derived from Salmonella typhimurium, S...

  17. Purification of a lectin from Eugenia uniflora L. seeds and its potential antibacterial activity.

    Science.gov (United States)

    Oliveira, M D L; Andrade, C A S; Santos-Magalhães, N S; Coelho, L C B B; Teixeira, J A; Carneiro-da-Cunha, M G; Correia, M T S

    2008-03-01

    The aim of this work was to analyse the antimicrobial properties of a purified lectin from Eugenia uniflora L. seeds. The E. uniflora lectin (EuniSL) was isolated from the seed extract and purified by ion-exchange chromatography in DEAE-Sephadex with a purification factor of 11.68. The purified lectin showed a single band on denaturing electrophoresis, with a molecular mass of 67 kDa. EuniSL agglutinated rabbit and human erythrocytes with a higher specificity for rabbit erythrocytes. The haemagglutination was not inhibited by the tested carbohydrates but glycoproteins exerted a strong inhibitory action. The lectin proved to be thermo resistant with the highest stability at pH 6.5 and divalent ions did not affect its activity. EuniSL demonstrated a remarkable nonselective antibacterial activity. EuniSL strongly inhibited the growth of Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella sp. with a minimum inhibitory concentration (MIC) of 1.5 microg ml(-1), and moderately inhibited the growth of Bacillus subtilis, Streptococcus sp. and Escherichia coli with a MIC of 16.5 microg ml(-1). EuniSL was found to be effective against bacteria. The strong antibacterial activity of the studied lectin indicates a high potential for clinical microbiology and therapeutic applications.

  18. Collectin-11/MASP complex formation triggers activation of the lectin complement pathway--the fifth lectin pathway initiation complex

    DEFF Research Database (Denmark)

    Ma, Ying Jie; Skjoedt, Mikkel-Ole; Garred, Peter

    2013-01-01

    Collectins and ficolins are important in the clearance of endogenous and exogenous danger materials. A new human collectin-11 was recently identified in low concentration in serum in complex with mannose-binding lectin (MBL)/ficolin-associated serine proteases. Collectin-11 binds to carbohydrate...... complement complex on C. albicans. Moreover, spiking collectin-11-depleted serum, which did not mediate complement activation, with recombinant collectin-11 restored the complement activation capability. These results define collectin-11 as the fifth recognition molecule in the lectin complement pathway...

  19. Ulex europaeus I lectin induces activation of matrix-metalloproteinase-2 in endothelial cells.

    Science.gov (United States)

    Gomez, D E; Yoshiji, H; Kim, J C; Thorgeirsson, U P

    1995-11-02

    In this report, we show that the lectin Ulex europaeus agglutinin I (UEA I), which binds to alpha-linked fucose residues on the surface of endothelial cells, mediates activation of the 72-kDa matrix metalloproteinase-2 (MMP-2). A dose-dependent increase in the active 62-kDa form of MMP-2 was observed in conditioned medium from monkey aortic endothelial cells (MAEC) following incubation with concentrations of UEA I ranging from 2 to 100 micrograms/ml. The increase in the 62-kDa MMP-2 gelatinolytic activity was not reflected by a rise in MMP-2 gene expression. The UEA I-mediated activation of MMP-2 was blocked by L-fucose, which competes with UEA I for binding to alpha-fucose. These findings may suggest that a similar in vivo mechanism exists, whereby adhesive interactions between tumor cell lectins and endothelial cells can mediate MMP-2 activation.

  20. Characterization of the yam tuber storage proteins from Dioscorea batatas exhibiting unique lectin activities.

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    Gaidamashvili, Mariam; Ohizumi, Yuki; Iijima, Shinichiro; Takayama, Tomo; Ogawa, Tomohisa; Muramoto, Koji

    2004-06-18

    Four major proteins designated DB1, DB2, DB3, and DB4 were isolated and characterized from the yam tuber Dioscorea batatas. The ratios of their yields were 20:50:20:10. DB1 was a mannose-binding lectin (20 kDa) consisting of 10-kDa subunits and was classified as the monocot mannose-binding lectin family. DB2, accounting for 50% of the total protein, was the storage protein, commonly called dioscorins consisting of a 31-kDa subunit. On the basis of amino acid sequence, DB2 was classified to be dioscorin A. DB3 was a maltose-binding lectin, having an apparent molecular mass of 120 kDa and composed of a 66-kDa subunit and two 31-kDa subunits (DB3S). The 66-kDa subunit was further composed of two 31-kDa subunits (DB3L) cross-linked by disulfide bonds. DB3L and DB3S (242 and 241 amino acid residues, respectively) were homologous with each other with 72% sequence identity. They showed a sequence homology to dioscorin B and dioscorin A from Dioscorea alata, with 90 and 93% identity, respectively, and to carbonic anhydrase from Arabidopsis thaliana with about 45% identity. DB3S had one intrachain disulfide bond located at Cys(28)-Cys(187), whereas DB3L had one interchain disulfide bond (Cys(40)-Cys(40)') in addition to the intrachain disulfide bond (Cys(28)-Cys(188)) to form a 66-kDa subunit. DB1 and DB3 agglutinated rabbit erythrocytes at 2.7 and 3.9 microg/ml, respectively. Despite the structural homology between DB2 and DB3, DB2 had no lectin activity. The 66-kDa subunit itself revealed the full hemagglutinating activity of DB3, indicating that DB3L but not DB3S was responsible for the activity. The hemagglutinating activity of DB3 required Ca(2+) ions and was exclusively inhibited by maltose and oligomaltoses (e.g. maltopentaose and maltohexaose) but not by d-glucose. DB3 could not be classified into any known plant lectin family. DB4 was a chitinase, homologous to an acidic chitinase from Dioscorea japonica. DB1, DB2, and DB3 did not show any activity of carbonic

  1. Plant Cell Protolytic Enzymes Activity under Exposure to Lectins of Endophytic and Epiphytic Azospirillum Strains

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    S.A. Alen’kina

    2016-05-01

    Full Text Available We studied the ability of lectins isolated from the surface of the two strains of nitrogen-fixing soil bacteria of the genus Azospirillum, A. brasilense Sp7 (epiphytic and A. brasilense Sp245 (endophytic, to show have a regulating effect on the activity of pectinolytic enzymes in the roots of wheat seedlings. Research results showed that the lectins under study can cause the induction of the activity of polygalacturonase, pectinesterase, pectatlyase from the plant cell wall, thereby ensuring the bacteria penetration in the plant tissues, as well as the induction of plants responses which, being combined with growth-stimulating effect of bacteria, contributes to the formation of plants stability and productivity.

  2. Activities of lectins and their immobilized derivatives in detergent solutions. Implications on the use of lectin affinity chromatography for the purification of membrane glycoproteins.

    Science.gov (United States)

    Lotan, R; Beattie, G; Hubbell, W; Nicolson, G L

    1977-05-03

    The effects of several commonly used detergents on the saccharide-binding activities of lectins were investigated using lectin-mediated agglutination of formalin-fixed erythrocytes and affinity chromatography of glycoproteins on columns of lectins immobilized on polyacrylic hydrazide-Sepharose. In the hemagglutination assays, Ricinus communis I (RCA1) and II (RCAII), concanavalin A (Con A), and the agglutinins from peanut (PNA), soybean (SBA), wheat germ (WGA), and Limulus polyphemus (LPA) were tested with several concentrations of switterionic, cationic, anionic, and nonionic detergents. It was found that increasing detergent concentrations eventually affected hemagglutination titers in both test and control samples, and the highest detergent concentrations not affecting lectin hemagglutinating activities were determined. The effects of detergents on specific binding of [3H]fetuin and asialo[3H]fetuin to and elution from columns of immobilized lectins were less severe when compared with lectins in solution, suggesting that the lectins are stabilized by covalent attachment to agarose beads. Nonionic detergents did not affect the binding efficiency of the immobilized lectins tested at concentrations used for membrane solubilization while cationic and zwitterionic detergents caused significant inhibition of Con A- and SBA-Sepharose activities. In sodium deoxycholate (greater than 1%) only RCAI-Sepharose retained its activity, whereas the activities of the other lectins were reduced dramatically. Low concentrations of sodium dodecyl sulfate (0.05%) inhibited only the activity of immobilized SBA, but at higher concentration (0.1%) and prolonged periods of incubation (16 h, 23 degrees C) most of the lectins were inactivated. These data are compared with previous reports on the use of detergents in lectin affinity chromatography, and the conditions for the optimal use of detergents are detailed.

  3. Lectin histochemistry and alkaline phosphatase activity in the pia mater vessels of spontaneously hypertensive rats (SHR).

    Science.gov (United States)

    Szumańska, G; Gadamski, R

    1992-01-01

    Some lectins were used to study the localization of sugar residues on the endothelial cell surface in the pia mater blood vessels of control (WKY) and hypertensive rats (SHR). The lectins tested recognized the following residues: beta-D-galactosyl (Ricinus communis agglutinin 120, RCA-1), alpha-L-fucosyl (Ulex europaeus agglutinin, UEA-1), N-acetylglucosaminyl and sialyl (Wheat germ agglutinin, WGA), N-glycolyl-neuraminic acid (Limax flavus agglutinin, LFA), and N-acetyl-D-galactosaminyl (Helix pomatia agglutinin, HPA). Several differences were revealed in the presence of sugar receptors on the surface of endothelial cells between the control and the hypertensive rats. Our studies showed also differences in the localization of the tested glycoconjugates between pial capillaries, small, medium-size and large pial arteries. The histochemical evaluation of alkaline phosphatase revealed an increased activity of the enzyme in the pial vessels of SHRs as compared with control rats with a similar localization of the enzyme activity. Some differences in the distribution of lectin binding sites and alkaline phosphatase activity could be associated with the different functions of particular segments of the pial vascular network.

  4. Purification of a novel chitin-binding lectin with antimicrobial and antibiofilm activities from a bangladeshi cultivar of potato (Solanum tuberosum).

    Science.gov (United States)

    Hasan, Imtiaj; Ozeki, Yasuhiro; Kabir, Syed Rashel

    2014-04-01

    A new chitin-binding lectin was purified from a Bangladeshi cultivar 'Deshi' of potato (Solanum tuberosum L.) through anion-exchange and affinity chromatographies using a chitin column. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) showed the molecular mass of the lectin as 20,000 Daltons. This molecular mass was almost half of the molecular masses of chitin-binding lectins derived from other potatoes. The lectin showed both bactericidal and growth-inhibiting activities against Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli, Salmonella enteritidis and Shigella boydii) pathogenic bacteria. It also showed antifungal activity against Rhizopus spp., Penicillium spp. and Aspergillus niger. Biofilm produced by the bacterium Pseudomonas aeruginosa was dose-dependently reduced by 5-20% in 24 h after administration of the lectin, which was attributed to the glycan-binding property of the lectin having affinity to GlcNAc polymers. It was the first observation that any potato lectin prevented biofilm formation by P. aeruginosa and, therefore, could have possible applications in clinical microbiology and biomedical science.

  5. Assessing biosafety of GM plants containing lectins

    DEFF Research Database (Denmark)

    Poulsen, Morten; Pedersen, Jan W.

    2010-01-01

    insects. However, since the cry genes are not active against all insects, e.g. sap-sucking insects, other genes coding for proteins such as lectins show promise of complementing the cry genes for insect resistance. As with other novel plants, lectin-expressing plants will need to be assessed...... for their potential risks to human and animal health and the environment. The expressed lectin protein should be assessed on its own for potential toxicity and allergenicity as for any other new protein. Although not many lectins have been thoroughly tested for their toxicity, our evaluation suggests that most...... of the lectins that are potentially useful for insect resistance will pose no health risk in genetically modified (GM) plants. Since some lectins are known for their toxicity to humans, the insertion of lectin genes in food crop plants will have to be assessed carefully. It is expected that in some cases...

  6. New perspectives on mannan-binding lectin-mediated complement activation

    DEFF Research Database (Denmark)

    Degn, Søren Egedal; Thiel, Steffen; Jensenius, Jens Christian

    2007-01-01

    The complement system is an important part of the innate immune system, mediating several major effector functions and modulating adaptive immune responses. Three complement activation pathways exist: the classical pathway (CP), the alternative pathway (AP), and the lectin pathway (LP). The LP......, allowing C3 activation in the absence of components otherwise believed critical. The classical bypass pathways are dependent on C1 and components of the AP. A recent study has shown the existence also of a lectin bypass pathway dependent on mannan-binding lectin (MBL) and AP components. The emerging...

  7. The identification of plant lectins with mucosal adjuvant activity

    Science.gov (United States)

    Lavelle, E C; Grant, G; Pusztai, A; Pfüller, U; O'hagan, D T

    2001-01-01

    To date, the most potent mucosal vaccine adjuvants to be identified have been bacterial toxins. The present data demonstrate that the type 2 ribosome-inactivating protein (type 2 RIP), mistletoe lectin I (ML-I) is a strong mucosal adjuvant of plant origin. A number of plant lectins were investigated as intranasal (i.n.) coadjuvants for a bystander protein, ovalbumin (OVA). As a positive control, a potent mucosal adjuvant, cholera toxin (CT), was used. Co-administration of ML-I or CT with OVA stimulated high titres of OVA-specific serum immunoglobulin G (IgG) in addition to OVA-specific IgA in mucosal secretions. CT and ML-I were also strongly immunogenic, inducing high titres of specific serum IgG and specific IgA at mucosal sites. None of the other plant lectins investigated significantly boosted the response to co-administered OVA. Immunization with phytohaemagglutinin (PHA) plus OVA elicited a lectin-specific response but did not stimulate an enhanced response to OVA compared with the antigen alone. Intranasal delivery of tomato lectin (LEA) elicited a strong lectin-specific systemic and mucosal antibody response but only weakly potentiated the response to co-delivered OVA. In contrast, administration of wheatgerm agglutinin (WGA) or Ulex europaeus lectin 1 (UEA-I) with OVA stimulated a serum IgG response to OVA while the lectin-specific responses (particularly for WGA) were relatively low. Thus, there was not a direct correlation between immunogenicity and adjuvanticity although the strongest adjuvants (CT, ML-I) were also highly immunogenic. PMID:11168640

  8. Lysis of fresh human solid tumors by autologous lymphocytes activated in vitro with lectins

    International Nuclear Information System (INIS)

    Mazumder, A.; Grimm, E.A.; Zhang, H.Z.; Rosenberg, S.A.

    1982-01-01

    Human peripheral blood lymphocytes (PBL), obtained from patients with a variety of cancers, were incubated in vitro with phytohemagglutinin, concanavalin A, and crude or lectin-free T-cell growth factors. The lectin-activated PBL of nine patients were capable of lysing fresh autologous tumor during a 4-hr 51Cr release assay. Multiple metastases from the same patient were equivalently lysed by these activated autologous PBL. No lysis of fresh PBL or lectin-induced lymphoblast cell targets was seen, although tumor, PBL, and lymphoblast cells were shown to be equally lysable using allosensitized cells. The activated cells could be expanded without loss of cytotoxicity in crude or lectin-free T-cell growth factors. The generation of cells lytic to fresh autologous tumor was dependent on the presence of adherent cells, although the lytic cell itself was not adherent. Proliferation was not involved in the induction of lytic cells since equal lysis was induced in irradiated and nonirradiated lymphocytes. Lectin was not required in the lytic assay, and the addition of alpha-methyl-D-mannoside to concanavalin A-activated lymphoid cells did not increase the lysis of fresh tumor cells. Activation by lectin for 3 days appears to be an efficient and convenient method for generating human cells lytic to fresh autologous tumor. These lytic cells may be of value for studies of the cell-mediated lysis of human tumor and possibly for tumor immunotherapy as well

  9. [Effect of Azospirillum lectins on the Activity of Proteolytic Enzymes and Their Inhibitors in Wheat Seedling Roots].

    Science.gov (United States)

    Alen'kina, S A; Nikitina, V E

    2015-01-01

    The lectins of associative nitrogen-fixing strains Azospirillum brasilense Sp7 and Sp245 were shown to exerte a multidirectional effect on the activity of acidic (pH 3.5), neutral (6.8), and alkaline (pH 7.8) proteinases. The lectin of the epiphytic A. brasilense Sp7 decreased proteolytic activity at all pH values, whereas the lectin of the endophytic A. brasilense Sp245 activated neutral and alkaline proteinases, while not affecting the alkaline ones. Experiments with protease inhibitors made it possible to conclude that the lectins of the studied A. brasilense strains alter the ratio between the activities of different protease types in germinating seeds. The activity of trypsin inhibitors in wheat seedling roots was found to increase in the presence of the lectins. Our results indicate a broader spectrum of effects of azospirilla lectins on the host plant organism.

  10. Activation of the lectin pathway of complement in experimental human keratitis with Pseudomonas aeruginosa.

    Science.gov (United States)

    Osthoff, Michael; Brown, Karl D; Kong, David C M; Daniell, Mark; Eisen, Damon P

    2014-01-01

    Pseudomonas aeruginosa (P. aeruginosa) microbial keratitis (MK) is a sight-threatening disease. Previous animal studies have identified an important contribution of the complement system to the clearance of P. aeruginosa infection of the cornea. Mannose-binding lectin (MBL), a pattern recognition receptor of the lectin pathway of complement, has been implicated in the host defense against P. aeruginosa. However, studies addressing the role of the lectin pathway in P. aeruginosa MK are lacking. Hence, we sought to determine the activity of the lectin pathway in human MK caused by P. aeruginosa. Primary human corneal epithelial cells (HCECs) from cadaveric donors were exposed to two different P. aeruginosa strains. Gene expression of interleukin (IL)-6, IL-8, MBL, and other complement proteins was determined by reverse transcription-polymerase chain reaction (RT-PCR) and MBL synthesis by enzyme-linked immunosorbent assay and intracellular flow cytometry. MBL gene expression was not detected in unchallenged HCECs. Exposure of HCECs to P. aeruginosa resulted in rapid induction of the transcriptional expression of MBL, IL-6, and IL-8. In addition, expression of several complement proteins of the classical and lectin pathways, but not the alternative pathway, were upregulated after 5 h of challenge, including MBL-associated serine protease 1. However, MBL protein secretion was not detectable 18 h after challenge with P. aeruginosa. MK due to P. aeruginosa triggers activation of MBL and the lectin pathway of complement. However, the physiologic relevance of this finding is unclear, as corresponding MBL oligomer production was not observed.

  11. Antiproliferative activity of cytotoxic tuber lectins from Solanum ...

    African Journals Online (AJOL)

    SAM

    2014-04-09

    Apr 9, 2014 ... E-mail: hasanimtiaj@yahoo.co.uk, rashelkabir@ru.ac.bd. .... blue and then counted by a hemocytometer under an inverted microscope (XDS-1R .... and lectin-treated mice counted by a light microscope on day. 6 of tumor ...

  12. Pseudomonas aeruginosa alkaline protease blocks complement activation via the classical and lectin pathways.

    Science.gov (United States)

    Laarman, Alexander J; Bardoel, Bart W; Ruyken, Maartje; Fernie, Job; Milder, Fin J; van Strijp, Jos A G; Rooijakkers, Suzan H M

    2012-01-01

    The complement system rapidly detects and kills Gram-negative bacteria and supports bacterial killing by phagocytes. However, bacterial pathogens exploit several strategies to evade detection by the complement system. The alkaline protease (AprA) of Pseudomonas aeruginosa has been associated with bacterial virulence and is known to interfere with complement-mediated lysis of erythrocytes, but its exact role in bacterial complement escape is unknown. In this study, we analyzed how AprA interferes with complement activation and whether it could block complement-dependent neutrophil functions. We found that AprA potently blocked phagocytosis and killing of Pseudomonas by human neutrophils. Furthermore, AprA inhibited opsonization of bacteria with C3b and the formation of the chemotactic agent C5a. AprA specifically blocked C3b deposition via the classical and lectin pathways, whereas the alternative pathway was not affected. Serum degradation assays revealed that AprA degrades both human C1s and C2. However, repletion assays demonstrated that the mechanism of action for complement inhibition is cleavage of C2. In summary, we showed that P. aeruginosa AprA interferes with classical and lectin pathway-mediated complement activation via cleavage of C2.

  13. [Inhibition by cysteine of the carbohydrate-binding activity of lectins from Ricinus communis, Canavalia ensiformis and Euonymus europaeus].

    Science.gov (United States)

    Dvorkin, V M

    1985-10-01

    Precipitation induced by different lectins has been studied in the presence of some aminoacids. It was shown that precipitates formed by lectins from Ricinus communis (RCA1), Canavalia ensiformis (Con A), Euonymus europaeus (Eel) in the presence of appropriate carbohydrate-containing molecules disappeared after cysteine addition, like after addition of specific carbohydrate precipitation inhibitors. It is assumed that cysteine residues of RCA1, Con A and Eel lectins are essential for their carbohydrate binding activity.

  14. Detection of Cytotoxic Activity of Lectin on Human Colon Adenocarcinoma (Sw480 and Epithelial Cervical Carcinoma (C33-A

    Directory of Open Access Journals (Sweden)

    Mirandeli Bautista

    2011-03-01

    Full Text Available Lectins comprise a heterogeneous class of proteins that recognize the carbohydrate moieties of glycoconjugates with high specificity. Numerous studies have shown that lectins are capable of recognizing specific carbohydrate moieties displayed by malignant cells or tissues. The present work was performed to investigate the effects of tepary bean (Phaseolus acutifolius lectins on proliferation, colony formation, and alteration of DNA synthesis of human malignant cells. Tepary bean lectin showed dose dependent  effects on the inhibition of viability as well as on colony formation in two human malignant cells lines (C33-A, Sw480; By contrast, tepary bean lectin only showed significant effects on DNA synthesis on Sw480 cells. Our results provide evidence of the anti- proliferative and cytotoxic effects of the tepary bean lectins on C33-A and Sw480 cells lines.

  15. The cyanobacterial lectin scytovirin displays potent in vitro and in vivo activity against Zaire Ebola virus.

    Science.gov (United States)

    Garrison, Aura R; Giomarelli, Barbara G; Lear-Rooney, Calli M; Saucedo, Carrie J; Yellayi, Srikanth; Krumpe, Lauren R H; Rose, Maura; Paragas, Jason; Bray, Mike; Olinger, Gene G; McMahon, James B; Huggins, John; O'Keefe, Barry R

    2014-12-01

    The cyanobacterial lectin scytovirin (SVN) binds with high affinity to mannose-rich oligosaccharides on the envelope glycoprotein (GP) of a number of viruses, blocking entry into target cells. In this study, we assessed the ability of SVN to bind to the envelope GP of Zaire Ebola virus (ZEBOV) and inhibit its replication. SVN interacted specifically with the protein's mucin-rich domain. In cell culture, it inhibited ZEBOV replication with a 50% virus-inhibitory concentration (EC50) of 50 nM, and was also active against the Angola strain of the related Marburg virus (MARV), with a similar EC50. Injected subcutaneously in mice, SVN reached a peak plasma level of 100 nm in 45 min, but was cleared within 4h. When ZEBOV-infected mice were given 30 mg/kg/day of SVN by subcutaneous injection every 6h, beginning the day before virus challenge, 9 of 10 animals survived the infection, while all infected, untreated mice died. When treatment was begun one hour or one day after challenge, 70-90% of mice survived. Quantitation of infectious virus and viral RNA in samples of serum, liver and spleen collected on days 2 and 5 postinfection showed a trend toward lower titers in treated than control mice, with a significant decrease in liver titers on day 2. Our findings provide further evidence of the potential of natural lectins as therapeutic agents for viral infections. Published by Elsevier B.V.

  16. Mannose-binding lectin impairs Leptospira activity through the inhibitory effect on the motility of cell.

    Science.gov (United States)

    Xu, Jun; Guo, Yijie; Nakamura, Shuichi; Islam, Md Shafiqul; Tomioka, Rintaro; Yoneyama, Hiroshi; Isogai, Emiko

    2015-02-01

    Mannose-binding lectin (MBL) plays key role in lectin pathway of innate immunity, and shows the ability of triggering opsonization intermediately. Substantial increase in the serum level of MBL has been confirmed during leptospirosis, which caused by a pathogenic spirochete, Leptospira. Leptospira has a fascinating locomotion pattern, which simultaneously gyrating and swimming forward, such motility enables that Leptospira is difficult to be captured by immune cells if without any assistance. In this study, the effect of mannose-binding lectin to Leptospira was quantitatively investigated by measuring some kinematic parameters, to discover the mechanism behind MBL-mediated immune responses during leptospiral infection. The results showed that mannose-binding lectin is capable of inhibiting the motility of Leptospira by transforming free swimming cells to tumbled rotating cells, resulted in the increase number of rotating cells. Otherwise, decrease in rotation rate of rotating cell has been observed. However, the swimming speed of swimming Leptospira cells showed no observable change under the effect of MBL. The inhibitory effect were only valid in a relatively short period, Leptospira cells regained their original motility after 2 h. This raises an interesting topic that Leptospira is somehow able to escape from the inhibitory effect of MBL by dragging such unfavorable molecules toward to the cell end and eventually throwing it out. The inhibitory effect of MBL on the motility of Leptospira is expected to provide a new insight into lectin pathway. Copyright © 2015 Elsevier GmbH. All rights reserved.

  17. A fusion protein containing a lepidopteran-specific toxin from the South Indian red scorpion (Mesobuthus tamulus and snowdrop lectin shows oral toxicity to target insects

    Directory of Open Access Journals (Sweden)

    Fitches Elaine

    2006-03-01

    Full Text Available Abstract Background Despite evidence suggesting a role in plant defence, the use of plant lectins in crop protection has been hindered by their low and species-specific insecticidal activity. Snowdrop lectin (Galanthus nivalis agglutinin; GNA is transported to the haemolymph of insects after oral ingestion, and can be used as a basis for novel insecticides. Recombinant proteins containing GNA expressed as a fusion with a peptide or protein, normally only toxic when injected into the insect haemolymph, have the potential to show oral toxicity as a result of GNA-mediated uptake. Results A gene encoding a toxin, ButaIT, from the red scorpion (Mesobuthus tamulus was synthesised and assembled into expression constructs. One construct contained ButaIT alone, whereas the other contained ButaIT fused N-terminally to a GNA polypeptide (ButaIT/GNA. Both recombinant proteins were produced using the yeast Pichia pastoris as an expression host, and purified. Recombinant ButaIT and ButaIT/GNA were acutely toxic when injected into larvae of tomato moth (Lacanobia oleracea, causing slow paralysis, leading to mortality or decreased growth. ButaIT/GNA was chronically toxic when fed to L. oleracea larvae, causing decreased survival and weight gain under conditions where GNA alone was effectively non-toxic. Intact ButaIT/GNA was detected in larval haemolymph from insects fed the fusion protein orally, demonstrating transport of the linked polypeptide across the gut. Proteolysis of the fusion protein was also observed. ButaIT/GNA was significantly more toxic that GNA alone when fed to the homopteran Nilaparvata lugens (rice brown planthopper in liquid artificial diet. Conclusion The ButaIT/GNA recombinant fusion protein is toxic to lepidopteran larvae both when injected and when fed orally, showing the utility of GNA as a carrier to transport potentially toxic peptides and proteins across the insect gut. Although ButaIT has been claimed to be lepidopteran

  18. Direct demonstration of the lectin activity of gp90MEL, a lymphocyte homing receptor

    Science.gov (United States)

    1990-01-01

    Considerable evidence implicates gp90MEL as a lymphocyte homing receptor mediating lymphocyte attachment to high endothelial venules of lymph nodes in mouse. The protein appears to function as a calcium- dependent, lectin-like receptor as inferred primarily by the ability of specific carbohydrates to block its function and by the presence of a calcium-type lectin domain in its primary sequence. An ELISA assay is described which provides the first demonstration that the isolated protein has lectin activity and allows a further definition of its carbohydrate specificity. In addition to the monosaccharides mannose-6- phosphate and fructose-1-phosphate, ligand activity is shown for the sulfated glycolipid, sulfatide, and for two sulfated fucose-containing polysaccharides (fucoidin and egg jelly coat) from nonmammalian sources. PMID:2202735

  19. Lectin Pathway of Complement Activation Is Associated with Vulnerability of Atherosclerotic Plaques

    DEFF Research Database (Denmark)

    Fumagalli, Stefano; Perego, Carlo; Zangari, Rosalia

    2017-01-01

    Inflammatory mechanisms may be involved in atherosclerotic plaque rupture. By using a novel histology-based method to quantify plaque instability here, we assess whether lectin pathway (LP) of complement activation, a major inflammation arm, could represent an index of plaque instability. Plaques...

  20. Feline Lectin Activity Is Critical for the Cellular Entry of Feline Infectious Peritonitis Virus▿

    OpenAIRE

    Regan, Andrew D.; Ousterout, David G.; Whittaker, Gary R.

    2010-01-01

    Feline infectious peritonitis is a lethal disease of felids caused by systemic infection with a feline coronavirus. Here, we report identification and analysis of the feline homologue to the human lectin DC-SIGN and show that it is a coreceptor for virulent strains of serotype 1 and serotype 2 feline coronaviruses.

  1. Structural insights into the anti-HIV activity of the Oscillatoria agardhii agglutinin homolog lectin family.

    Science.gov (United States)

    Koharudin, Leonardus M I; Kollipara, Sireesha; Aiken, Christopher; Gronenborn, Angela M

    2012-09-28

    Oscillatoria agardhii agglutinin homolog (OAAH) proteins belong to a recently discovered lectin family. All members contain a sequence repeat of ~66 amino acids, with the number of repeats varying among different family members. Apart from data for the founding member OAA, neither three-dimensional structures, information about carbohydrate binding specificities, nor antiviral activity data have been available up to now for any other members of the OAAH family. To elucidate the structural basis for the antiviral mechanism of OAAHs, we determined the crystal structures of Pseudomonas fluorescens and Myxococcus xanthus lectins. Both proteins exhibit the same fold, resembling the founding family member, OAA, with minor differences in loop conformations. Carbohydrate binding studies by NMR and x-ray structures of glycan-lectin complexes reveal that the number of sugar binding sites corresponds to the number of sequence repeats in each protein. As for OAA, tight and specific binding to α3,α6-mannopentaose was observed. All the OAAH proteins described here exhibit potent anti-HIV activity at comparable levels. Altogether, our results provide structural details of the protein-carbohydrate interaction for this novel lectin family and insights into the molecular basis of their HIV inactivation properties.

  2. Galactose-binding lectin from mulberry (Morus alba L. seeds with growth hormone-like activity

    Directory of Open Access Journals (Sweden)

    E. Khurtsidze

    2017-03-01

    Full Text Available Plant lectins are well documented to participate in multiple physiological activities based on selective binding to the carbohydrate structures. They have been reported to play significant roles in various processes such as growth and development, differentiation and plant protection. Nevertheless, the intrinsic roles of plant lectins still remain undefined. We purified a galactose-binding lectin, named MAL, from mulberry (M. alba L. seeds and analyzed its properties. The lectin is composed of one polypeptide of 17 kDa, which is abundant in the seed protein fraction. MAL interacted with GalNAc and galactose residues of saccharides with high binding ability. Western blotting analysis suggested that MAL is deposited in the mulberry leaves and inflorescence. MAL was examined for growth stimulatory activity on mulberry hypocotyls and internodal sections of in vitro grown P. euphratica cultures. Elongation of mulberry hypocotyls was detected in the apical parts of the hypocotyl, where the growth increment was 58%. MAL had no significant effect on the stem elongation and induction of new leaves. Our results suggest that MAL may be involved in the growth and cell elongation at initial stages of tissue development.

  3. Lectin staining shows no evidence of involvement of glycocalyx/mucous layer carbohydrate structures in development of celiac disease

    DEFF Research Database (Denmark)

    Toft-Hansen, Henrik; Nielsen, Christian; Biagini, Matteo

    2013-01-01

    were examined before and after remission following a gluten-free diet. We performed lectin histochemistry using peanut agglutinin (PNA) and Ulex europaeus agglutinin (UEA) staining for Gal-β(1,3)-GalNAc and Fucα1-2Gal-R, respectively, of the glycocalyx/mucous layer. The staining was scored based...

  4. Lectin Staining Shows no Evidence of Involvement of Glycocalyx/Mucous Layer Carbohydrate Structures in Development of Celiac Disease

    Directory of Open Access Journals (Sweden)

    Henrik Toft-Hansen

    2013-11-01

    Full Text Available The presence of unique carbohydrate structures in the glycocalyx/mucous layer of the intestine may be involved in a susceptibility to celiac disease (CD by serving as attachment sites for bacteria. This host-microbiota interaction may influence the development of CD and possibly other diseases with autoimmune components. We examined duodenal biopsies from a total of 30 children, of which 10 had both celiac disease (CD and type 1 diabetes (T1D; 10 had CD alone; and 10 were suspected of having gastrointestinal disease, but had normal duodenal histology (non-CD controls. Patients with both CD and T1D were examined before and after remission following a gluten-free diet. We performed lectin histochemistry using peanut agglutinin (PNA and Ulex europaeus agglutinin (UEA staining for Gal-β(1,3-GalNAc and Fucα1-2Gal-R, respectively, of the glycocalyx/mucous layer. The staining was scored based on dissemination of stained structures on a scale from 0 to 3. Evaluation of the scores revealed no difference between biopsies obtained before and after remission in the group of children with both CD and T1D. A comparison of this pre-remission group with the children who had CD alone or the non-CD controls also showed no significant differences. Based on our material, we found no indication that the presence of Gal-β(1,3-GalNAc or Fucα1-2Gal-R is involved in the susceptibility to CD, or that the disease process affects the expression of these carbohydrates.

  5. Lectin Staining Shows no Evidence of Involvement of Glycocalyx/Mucous Layer Carbohydrate Structures in Development of Celiac Disease

    Science.gov (United States)

    Toft-Hansen, Henrik; Nielsen, Christian; Biagini, Matteo; Husby, Steffen; Lillevang, Søren T.

    2013-01-01

    The presence of unique carbohydrate structures in the glycocalyx/mucous layer of the intestine may be involved in a susceptibility to celiac disease (CD) by serving as attachment sites for bacteria. This host-microbiota interaction may influence the development of CD and possibly other diseases with autoimmune components. We examined duodenal biopsies from a total of 30 children, of which 10 had both celiac disease (CD) and type 1 diabetes (T1D); 10 had CD alone; and 10 were suspected of having gastrointestinal disease, but had normal duodenal histology (non-CD controls). Patients with both CD and T1D were examined before and after remission following a gluten-free diet. We performed lectin histochemistry using peanut agglutinin (PNA) and Ulex europaeus agglutinin (UEA) staining for Gal-β(1,3)-GalNAc and Fucα1-2Gal-R, respectively, of the glycocalyx/mucous layer. The staining was scored based on dissemination of stained structures on a scale from 0 to 3. Evaluation of the scores revealed no difference between biopsies obtained before and after remission in the group of children with both CD and T1D. A comparison of this pre-remission group with the children who had CD alone or the non-CD controls also showed no significant differences. Based on our material, we found no indication that the presence of Gal-β(1,3)-GalNAc or Fucα1-2Gal-R is involved in the susceptibility to CD, or that the disease process affects the expression of these carbohydrates. PMID:24253051

  6. The C-type lectin of the aggrecan G3 domain activates complement.

    Directory of Open Access Journals (Sweden)

    Camilla Melin Fürst

    Full Text Available Excessive complement activation contributes to joint diseases such as rheumatoid arthritis and osteoarthritis during which cartilage proteins are fragmented and released into the synovial fluid. Some of these proteins and fragments activate complement, which may sustain inflammation. The G3 domain of large cartilage proteoglycan aggrecan interacts with other extracellular matrix proteins, fibulins and tenascins, via its C-type lectin domain (CLD and has important functions in matrix organization. Fragments containing G3 domain are released during normal aggrecan turnover, but increasingly so in disease. We now show that the aggrecan CLD part of the G3 domain activates the classical and to a lesser extent the alternative pathway of complement, via binding of C1q and C3, respectively. The complement control protein (CCP domain adjacent to the CLD showed no effect on complement initiation. The binding of C1q to G3 depended on ionic interactions and was decreased in D2267N mutant G3. However, the observed complement activation was attenuated due to binding of complement inhibitor factor H to CLD and CCP domains. This was most apparent at the level of deposition of terminal complement components. Taken together our observations indicate aggrecan CLD as one factor involved in the sustained inflammation of the joint.

  7. Increased activity of the mannan-binding lectin complement activation pathway in patients with colorectal cancer

    DEFF Research Database (Denmark)

    Ytting, H; Jensenius, Jens Christian; Christensen, I J

    2004-01-01

    BACKGROUND: Postoperative bacterial infectious complications are frequent in patients with colorectal cancer (CRC), with subsequent increased recurrence rates and poor prognosis. Deficiency of the mannan-binding lectin (MBL) complement activation pathway may cause increased risk of infection......: Serum MBL concentrations and MBL/MASP activity were determined using immunofluorometric assays. The levels are presented as the median, inter-quartile range and range. RESULTS: Serum MBL levels were significantly (P cancer (1384 (400-2188) ng/mL) (median...... in the colon or rectum, and disease stages according to Dukes' classification. No statistical difference (P=0.20) in frequency of MBL deficiency was found between the patients (20%) and the donors (27%). CONCLUSIONS: Overall, the MBL complement activation pathway is significantly increased in patients...

  8. The lectin pathway of complement activation is a critical component of the innate immune response to pneumococcal infection

    DEFF Research Database (Denmark)

    Ali, Youssif M; Lynch, Nicholas J; Haleem, Kashif S

    2012-01-01

    The complement system plays a key role in host defense against pneumococcal infection. Three different pathways, the classical, alternative and lectin pathways, mediate complement activation. While there is limited information available on the roles of the classical and the alternative activation...... to pneumococcal infection and fail to opsonize Streptococcus pneumoniae in the none-immune host. This defect in complement opsonisation severely compromises pathogen clearance in the lectin pathway deficient host. Using sera from mice and humans with defined complement deficiencies, we demonstrate that mouse...... of C4. This study corroborates the essential function of MASP-2 in the lectin pathway and highlights the importance of MBL-independent lectin pathway activation in the host defense against pneumococci....

  9. Butterfly extracts show antibacterial activity

    Science.gov (United States)

    Extracts of several British butterfly species were tested and shown to possess powerful bactericidal activity against the gram-positive bacteria Staphylococcus aureus (S. aureus). The active compounds were identified as hydroxylated pyrrolizidine alkaloids (PAs) related to loline with nitrogen at C-...

  10. Lectin binders

    International Nuclear Information System (INIS)

    Rudiger, H.; Gebauer, G.; Gansera, R.; Schurz, H.; Schimpl, A.

    1982-01-01

    Lectins are widely distributed in the plant kingdom, many of them being well characterized in their chemical structure and the effects they have on alien biological systems such as erythrocytes or lymphocytes. The biological function of plant lectins remains speculative. We therefore inspected plant extracts from components which might bind specifically to the lectin from the respective plant. Single proteins (lectin binders) could be isolated from each plant extract. The interaction of these proteins with lectins was demonstrated and qualified by several methods. Similar to the lectins, the lectin binders are localized in the cytoplasm in contrast to them, however, they persist during germination and plant growth. Their precise role in the plant is not known, but they are likely to be associated with lectins not only in vitro but also in vivo. They also interact with alien cells, and are able to stimulate mitosis in murine lymphocytes. Some lectin binders act specifically on B lymphocytes, leaving T cells uninfluenced

  11. Comparisons of labeling efficiency, biological activity and biodistribution among 125I, 67Ga-DTPA- and 67Ga-DFO-lectins

    International Nuclear Information System (INIS)

    Kojima, Shuji; Jay, M.

    1987-01-01

    The labeling efficiency, biological activity and biodistribution of 125 I labeled and 67 Ga chelating agent conjugated lectins were investigated. Pisum sativum agglutinin (PSA) and Lens culinaris agglutinin (LCH) were efficiently labeled with 67 Ga using bifunctional chelating agents such as diethylenetriaminepentaacetic acid (DTPA) and deferoxamine (DFO), whereas labeling with 125 I was significantly less efficient. The agglutinating activity of these lectins towards Ehrlich ascites tumor (EAT) cells was retained on conjugation with DFO, but not with DTPA. The in vitro binding ratio of 67 Ga-DFO-lectins for EAT cells was almost the same as that of 125 I-lectins. However, the value was significantly decreased in the case of 67 Ga-DTPA-lectins. In the biodistribution study of radiolabeled lectins in Ehrlich solid tumor (EST) bearing mice, the accumulation of radioactivity in tumor tissue was very much less with 67 Ga-DTPA-lectins than with 125 I-lectins. However, the concentration was significantly elevated in the case of 67 Ga-DFO-lectins. While, these lectins accumulated in liver, spleen, lung, and kidney to a greater extent than 67 Ga citrate, the tumor to organ ratios became very low. These low tumor to organ ratios, in contrast to 67 Ga citrate, will certainly inhibit the tumor delineation, and therefore it seems that in spite of a high accumulation ratio of 67 Ga-DFO-lectins in tumor tissue, these agents are not useful in tumor detection. (orig.)

  12. Activity and Safety of Synthetic Lectins Based on Benzoboroxole-Functionalized Polymers for Inhibition of HIV Entry

    Science.gov (United States)

    Mahalingam, Alamelu; Geonnotti, Anthony R.; Balzarini, Jan; Kiser, Patrick F.

    2011-01-01

    Lectins derived from plant and microbial sources constitute a vital class of entry inhibitors that target the oligomannose residues on the HIV envelope gp120. Despite their potency and specificity, success of lectin-based entry inhibitors may be impeded by issues in regards to economical production, formulation and potential mitogenicity. Therefore, there exists a gap in the HIV therapeutics pipeline that underscores the need for mass producible, synthetic, broad-spectrum, and biocomptabile inhibitors of HIV entry. Here, we present the development of a polymeric synthetic lectin, based on benzoboroxole (BzB), which exhibits weak affinity (~25 M−1) for non-reducing sugars, similar to those found on the HIV envelope. High molecular weight BzB-functionalized polymers demonstrated antiviral activity that increased with an increase in ligand density and molecular weight of the polymer construct; revealing that polyvalency improves activity. Polymers showed significant increase in activity from 25 to 75 mol% BzB functionalization with EC50 of 15 μM and 15 nM, respectively. A further increase in mole functionalization to 90% resulted in an increase of the EC50 (59 ± 5 nM), likely due to the elongated rigid structure of the polymer chain compelled by electrostatic repulsion between the boronic acid groups. An increase in molecular weight of the polymer at 50 mol% BzB functionalization showed a gradual but significant increase in antiviral activity, with the highest activity seen with the 382 kDa polymer (EC50 of 1.1 ± 0.5 nM in CEM cells and 11 ± 3 nM in TZM-bl cells). Supplementing the polymer backbone with 10 mol% sulfonic acid not only increased the aqueous solubility of the polymers by at least 50-fold, but also demonstrated a synergistic increase in anti-HIV activity (4.0 ± 1.5 nM in TZM-bl cells), possibly due to electrostatic interactions between the negatively charged polymer backbone and the positively charged V3-loop in the gp120. The benzoboroxole

  13. Deposition of mannose-binding lectin and ficolins and activation of the lectin pathway of complement on the surface of polyurethane tubing used for cardiopulmonary bypass.

    Science.gov (United States)

    Eppa, Łukasz; Pągowska-Klimek, Izabela; Świerzko, Anna S; Moll, Maciej; Krajewski, Wojciech R; Cedzyński, Maciej

    2018-04-01

    The artificial surface used for cardiopulmonary bypass (CPB) is a crucial factor activating the complement system and thus contributing to the generation of a systemic inflammatory response. The activation of classical and alternative pathways on this artificial surface is well known. In contrast, lectin pathway (LP) activation has not been fully investigated, although noted during CPB in several studies. Moreover, we have recently proved the contribution of the LP to the generation of the systemic inflammatory response syndrome after pediatric cardiac surgery. The aim of this study was to assess LP-mediated complement activation on the surface of polyurethane CPB circuit tubing (noncoated Chalice ® ), used for CPB procedures in children with congenital heart disease. We found deposition of mannose-binding lectin, ficolin-1, -2, and -3 on the surface of unused tubing and on tubing used for CPB from a small minority of patients. Furthermore, we observed deposition of complement C4 activation products on tubing used for CPB and previously unused tubing after incubation with normal serum. The latter finding indicates LP activation in vitro on the polyurethane surface. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1202-1208, 2018. © 2017 Wiley Periodicals, Inc.

  14. Bivalent Carbohydrate Binding Is Required for Biological Activity of Clitocybe nebularis Lectin (CNL), the N,N′-Diacetyllactosediamine (GalNAcβ1–4GlcNAc, LacdiNAc)-specific Lectin from Basidiomycete C. nebularis*

    Science.gov (United States)

    Pohleven, Jure; Renko, Miha; Magister, Špela; Smith, David F.; Künzler, Markus; Štrukelj, Borut; Turk, Dušan; Kos, Janko; Sabotič, Jerica

    2012-01-01

    Lectins are carbohydrate-binding proteins that exert their biological activity by binding to specific cell glycoreceptors. We have expressed CNL, a ricin B-like lectin from the basidiomycete Clitocybe nebularis in Escherichia coli. The recombinant lectin, rCNL, agglutinates human blood group A erythrocytes and is specific for the unique glycan N,N′-diacetyllactosediamine (GalNAcβ1–4GlcNAc, LacdiNAc) as demonstrated by glycan microarray analysis. We here describe the crystal structures of rCNL in complex with lactose and LacdiNAc, defining its interactions with the sugars. CNL is a homodimeric lectin, each of whose monomers consist of a single ricin B lectin domain with its β-trefoil fold and one carbohydrate-binding site. To study the mode of CNL action, a nonsugar-binding mutant and nondimerizing monovalent CNL mutants that retain carbohydrate-binding activity were prepared. rCNL and the mutants were examined for their biological activities against Jurkat human leukemic T cells and the hypersensitive nematode Caenorhabditis elegans mutant strain pmk-1. rCNL was toxic against both, although the mutants were inactive. Thus, the bivalent carbohydrate-binding property of homodimeric CNL is essential for its activity, providing one of the rare pieces of evidence that certain activities of lectins are associated with their multivalency. PMID:22298779

  15. Evaluation of lectin pathway activity and mannan-binding lectin levels in the course of pregnancy complicated by diabetes type 1, based on the genetic background.

    Science.gov (United States)

    Pertyńska Marczewska, Magdalena; Cedzyński, Maciej; Swierzko, Anna; Szala, Agnieszka; Sobczak, Małgorzata; Cypryk, Katarzyna; Wilczyński, Jan

    2009-01-01

    There are numerous indications that either mannan-binding lectin (MBL) deficiency or its excessive activity are associated with adverse pregnancy outcomes. High MBL concentrations and corresponding MBL2 genotypes were shown to be associated with microvascular complications in type 1 diabetes. The aim of this study was to evaluate levels of MBL and MBL-dependent activity of the lectin pathway (LP) of complement in the course of pregnancy in diabetic mothers, based on genetic background. These parameters were determined in samples from healthy non-pregnant (control), diabetic non-pregnant, healthy pregnant, and pregnant diabetic women. No significant differences in median MBL levels or LP activities were found in any study group compared to the control. However, statistically significant differences in MBL levels were noted during pregnancy between the 1st and 3rd trimesters in both healthy controls and pregnant diabetics. With regard to LP values, similar trends were evident, but statistically significant results were obtained only in the healthy pregnant group. When data analysis was confined to patients carrying the A/A (wild-type) MBL2 genotype, an increase in MBL level during pregnancy (in both healthy and diabetic pregnant women) was still observed. Similarly, LP activity increased during both healthy and diabetic pregnancies, significantly so for the former. Diabetes, an autoimmune disease, is a serious complication of pregnancy. Therefore, determination of MBL status might be beneficial in identifying type 1 diabetic patients who are at increased risk of developing both vascular complications and poor pregnancy outcomes.

  16. LECTINS OF REPRESENTATIVES OF THE ECHINACEA GENUS (ECHINACEA MOENCH). 3. RESEARCH OF ACTIVITY IN ONTOGENESIS ECHINACEA PALLIDA (NUTT.) NUTT

    OpenAIRE

    Поспелов, Сергей Викторович

    2013-01-01

    For the first time research of dynamics of lectins activity of pale purple coneflower (Echinacea pallida (Nutt.) Nutt) in ontogenesis. It has been established that on the first year of vegetation the highest level of phytolectins observed in herbs at the second part of vegetation (14,0–16,0 point). In the roots with rhizomes lectins were appears only at the end of vegetation (up to 2,0 point). In the second year in the genesic period some high activity was observed of leave’s extracts at the ...

  17. Antitumor activity of the Korean mistletoe lectin is attributed to activation of macrophages and NK cells.

    Science.gov (United States)

    Yoon, Taek Joon; Yoo, Yung Choon; Kang, Tae Bong; Song, Seong Kyu; Lee, Kyung Bok; Her, Erk; Song, Kyung Sik; Kim, Jong Bae

    2003-10-01

    Inhibitory effect of the lectins (KML-C) isolated from Korean mistletoe (KM; Viscum album coloratum) on tumor metastases produced by murine tumor cells (B16-BL6 melanoma, colon 26-M3.1 carcinoma and L5178Y-ML25 lymphoma cells) was investigated in syngeneic mice. An intravenous (i.v.) administration of KML-C (20-50 ng/mouse) 2 days before tumor inoculation significantly inhibited lung metastases of both B16-BL6 and colon 26-M3.1 cells. The prophylactic effect of 50 ng/mouse of KML-C on lung metastasis was almost the same with that of 100 microg/mouse of KM. Treatment with KML-C 1 day after tumor inoculation induced a significant inhibition of not only the experimental lung metastasis induced by B16-BL6 and colon 26-M3.1 cells but also the liver and spleen metastasis of L5178Y-ML25 cells. Furthermore, multiple administration of KML-C given at 3 day-intervals after tumor inoculation led to a significant reduction of lung metastasis and suppression of the growth of B16-BL6 melanoma cells in a spontaneous metastasis model. In an assay for natural killer (NK) cell activity, i.v. administration of KML-C (50 ng/mouse) significantly augmented NK cytotoxicity against Yac-1 tumor cells 2 days after KML-C treatment. In addition, treatment with KML-C (50 ng/mouse) induced tumoricidal activity of peritoneal macrophages against B16-BL6 and 3LL cells. These results suggest that KML-C has an immunomodulating activity to enhance the host defense system against tumors, and that its prophylactic and therapeutic effect on tumor metastasis is associated with the activation of NK cells and macrophages.

  18. Chemical-modification studies of a unique sialic acid-binding lectin from the snail Achatina fulica. Involvement of tryptophan and histidine residues in biological activity.

    Science.gov (United States)

    Basu, S; Mandal, C; Allen, A K

    1988-01-01

    A unique sialic acid-binding lectin, achatininH (ATNH) was purified in single step from the haemolymph of the snail Achatina fulica by affinity chromatography on sheep submaxillary-gland mucin coupled to Sepharose 4B. The homogeneity was checked by alkaline gel electrophoresis, immunodiffusion and immunoelectrophoresis. Amino acid analysis showed that the lectin has a fairly high content of acidic amino acid residues (22% of the total). About 1.3% of the residues are half-cystine. The glycoprotein contains 21% carbohydrate. The unusually high content of xylose (6%) and fucose (2.7%) in this snail lectin is quite interesting. The protein was subjected to various chemical modifications in order to detect the amino acid residues and carbohydrate residues present in its binding sites. Modification of tyrosine and arginine residues did not affect the binding activity of ATNH; however, modification of tryptophan and histidine residues led to a complete loss of its biological activity. A marked decrease in the fluorescence emission was found as the tryptophan residues of ATNH were modified. The c.d. data showed the presence of an identical type of conformation in the native and modified agglutinin. The modification of lysine and carboxy residues partially diminished the biological activity. The activity was completely lost after a beta-elimination reaction, indicating that the sugars are O-glycosidically linked to the glycoprotein's protein moiety. This result confirms that the carbohydrate moiety also plays an important role in the agglutination property of this lectin. Images Fig. 3. PMID:3140796

  19. Ficolin-3-mediated lectin complement pathway activation in patients with subarachnoid hemorrhage

    DEFF Research Database (Denmark)

    Zanier, Elisa R; Zangari, Rosalia; Munthe-Fog, Lea

    2014-01-01

    OBJECTIVES: To assess the involvement of ficolin-3, the main initiator of the lectin complement pathway (LCP), in subarachnoid hemorrhage (SAH) pathology and outcome. METHODS: In this preliminary exploratory study, plasma concentration of ficolin-3 and of ficolin-3-mediated functional LCP activity...... the World Federation of Neurosurgical Societies grading scale; vasospasm, defined as neuro-worsening with angiographic confirmation of vessel narrowing; cerebral ischemia, defined as hypodense lesion on CT scan performed before discharge; and 6-month outcome, assessed using the Glasgow Outcome Scale....... RESULTS: In patients, no changes were detected for ficolin-3 compared with controls. Notably, however, ficolin-3-mediated functional LCP activity was reduced. Low levels of plasma ficolin-3 and ficolin-3-mediated functional LCP activity were related to SAH severity, vasospasm, and cerebral ischemia...

  20. Change in the Content of Salicylic Acid and in the Activities of Phenylalanine Ammonia-Lyase and Catalase in Wheat Seedling Roots Under the Effect of Azospirillum Lectins

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    Alen'kina S.A.

    2012-05-01

    Full Text Available We investigated the time course of changes in the endogenous content of salicylic acid, the ratio between the acid's free and bound forms, and changes in the activities of phenylalanine ammonia-lyase and catalase in wheat seedling roots under the effect of the lectins of two strains of the associative nitrogen-fixing bacterium Azospirillum: A. brasilense Sp7 and its mutant defective in lectin activity, A. brasilense Sp7.2.3. Differences in plant response to the action of the lectins from these two strains were established. On the basis of the obtained data, a model was proposed for lectin-assisted induction of resistance, according to which the lectin effect on the roots of seedlings results in accumulation of free salicylic acid, which inhibits catalase activity, ultimately leading to accumulation of hydrogen peroxide and to formation of induced resistance.

  1. Binding properties of a blood group Le(a+) active sialoglycoprotein, purified from human ovarian cyst, with applied lectins.

    Science.gov (United States)

    Wu, A M; WU, J H; Watkins, W M; Chen, C P; Tsai, M C

    1996-06-07

    Studies on the structures and binding properties of the glycoproteins, purified from human ovarian cyst fluids, will aid the understanding of the carbohydrate alterations occurring during the biosynthesis of blood group antigens and neoplasm formation. These glycoproteins can also serve as important biological materials to study blood group A, B, H, Le(a), Le(b), Le(x), Le(y), T and Tn determinants, precursor type I and II sequences and cold agglutinin I and i epitopes. In this study, the binding property of a cyst glycoprotein from a human blood group Le(a+) nonsecretor individual, that contains an unusually high amount (18%) of sialic acid (HOC 350) was characterized by quantitative precipitin assay with a panel of lectins exhibiting a broad range of carbohydrate-binding specificities. Native HOC 350 reacted well only with three out of nineteen lectins tested. It precipitated about 80% of Ricinus communis (RCA1), 50% of Triticum vulgaris (WGA) and 37% of Bauhinia purpurea aba (BPA) agglutinins, respectively. However, its asialo product had dramatically enhanced reactivity and reacted well with many I/II (Gal beta1 --> 3/4GcNAc), T(Gal beta1 --> 3GalNAc) and Tn(GaNIAc alphaI --> Ser/Thr) active lectins. It bound best to Jacalin, BPA, and abrin-a and completely precipitated all the lectins added. Asialo-HOC 350 also reacted strongly with Wistaria floribunda, Abrus precatorius agglutinin, ricin and RCA1 and precipitated over 75% of the lectin nitrogen added, and moderately with Arachis hypogaea, Maclura pomifera, WGA, Vicia viosa-B4, Codium fragile tomentosoides and Ulex europaeus-II. But native HOC 350 and its asialo product reacted not at all or poorly with Dolichos biflorus, Helix pomatia, Lotus tetra-gonolobus, Ulex europaeus-I, Lens culinaris lectins and Con A. The lectin-glycoform interactions through bioactive sugars were confirmed by precipitin inhibition assay. Mapping the precipitation profiles of the interactions have led to the conclusion that HOC 350

  2. High molecular weight lectin isolated from the mucus of the giant African snail Achatina fulica.

    Science.gov (United States)

    Ito, Shigeru; Shimizu, Masahiro; Nagatsuka, Maki; Kitajima, Seiji; Honda, Michiyo; Tsuchiya, Takahide; Kanzawa, Nobuyuki

    2011-01-01

    To understand better the host defense mechanisms of mollusks against pathogens, we examined the anti-microbial activity of mucus from the giant African snail Achatina fulica. Hemagglutination activity of the mucus secreted by the integument of snails inoculated with Escherichia coli was observed to increase and to cause hemagglutination of rabbit red blood cells. Purification of the snail mucus lectin by sequential column chromatography revealed that the relative molecular mass of the lectin was 350 kDa. The hemagglutination activity of the lectin was Ca(2+)-dependent and was inhibited by galactose. Growth arrest tests showed that the lectin did not inhibit bacterial growth, but did induce agglutination of gram-positive and gram-negative bacteria. Tissue distribution analyses using a polyclonal antibody revealed that the lectin was expressed in the tissues of the mantle collar. The lectin isolated from the mucus of the snail appeared to contribute to its innate immunity.

  3. Identification and Biological Activity of Synthetic Macrophage Inducible C-Type Lectin Ligands

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    Chriselle D. Braganza

    2018-01-01

    Full Text Available The macrophage inducible C-type lectin (Mincle is a pattern recognition receptor able to recognize both damage-associated and pathogen-associated molecular patterns, and in this respect, there has been much interest in determining the scope of ligands that bind Mincle and how structural modifications to these ligands influence ensuing immune responses. In this review, we will present Mincle ligands of known chemical structure, with a focus on ligands that have been synthetically prepared, such as trehalose glycolipids, glycerol-based ligands, and 6-acylated glucose and mannose derivatives. The ability of the different classes of ligands to influence the innate, and consequently, the adaptive, immune response will be described, and where appropriate, structure–activity relationships within each class of Mincle ligands will be presented.

  4. Lectins from Mycelia of Basidiomycetes

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    Valentina E. Nikitina

    2017-06-01

    Full Text Available Lectins are proteins of a nonimmunoglobulin nature that are capable of specific recognition of and reversible binding to the carbohydrate moieties of complex carbohydrates, without altering the covalent structure of any of the recognized glycosyl ligands. They have a broad range of biological activities important for the functioning of the cell and the whole organism and, owing to the high specificity of reversible binding to carbohydrates, are valuable tools used widely in biology and medicine. Lectins can be produced by many living organisms, including basidiomycetes. Whereas lectins from the fruit bodies of basidiomycetes have been studied sufficiently well, mycelial lectins remain relatively unexplored. Here, we review and comparatively analyze what is currently known about lectins isolated from the vegetative mycelium of macrobasidiomycetes, including their localization, properties, and carbohydrate specificities. Particular attention is given to the physiological role of mycelial lectins in fungal growth and development.

  5. Differential activity of a lectin from Solieria filiformis against human pathogenic bacteria

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    M.L. Holanda

    2005-12-01

    Full Text Available A lectin isolated from the red alga Solieria filiformis was evaluated for its effect on the growth of 8 gram-negative and 3 gram-positive bacteria cultivated in liquid medium (three independent experiments/bacterium. The lectin (500 µg/mL stimulated the growth of the gram-positive species Bacillus cereus and inhibited the growth of the gram-negative species Serratia marcescens, Salmonella typhi, Klebsiella pneumoniae, Enterobacter aerogenes, Proteus sp, and Pseudomonas aeruginosa at 1000 µg/mL but the lectin (10-1000 µg/mL had no effect on the growth of the gram-positive bacteria Staphylococcus aureus and B. subtilis, or on the gram-negative bacteria Escherichia coli and Salmonella typhimurium. The purified lectin significantly reduced the cell density of gram-negative bacteria, although no changes in growth phases (log, exponential and of decline were observed. It is possible that the interaction of S. filiformis lectin with the cell surface receptors of gram-negative bacteria promotes alterations in the flow of nutrients, which would explain the bacteriostatic effect. Growth stimulation of the gram-positive bacterium B. cereus was more marked in the presence of the lectin at a concentration of 1000 µg/mL. The stimulation of the growth of B. cereus was not observed when the lectin was previously incubated with mannan (125 µg/mL, its hapten. Thus, we suggest the involvement of the binding site of the lectin in this effect. The present study reports the first data on the inhibition and stimulation of pathogenic bacterial cells by marine alga lectins.

  6. Two acid RNases from Dactylis glomerata seeds. Purification, properties and effect of polyamines and lectins on their activity

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    Janina Wiśniowska

    2014-01-01

    Full Text Available Two glycoproteidic acid RNases (RNase I and RNase II were obtained and purified from the seeds of Dactylis glomerata by extraction with acetate buffer, fractionation with ammonium sulfate, ion-exchange chromatography on DEAE-cellulose, DEAE-Sphadex, affinity chromatography on Con A-Sepharose and gel filtration on Bio-Gel P60. RNase I with a specific activity of 2582 U•mg-1 protein and an optimum pH of 4.9 and RNase II with a specific activity of 1928 U• mg-1 protein and optimum pH of 4.6, were isolated. They lacked nuclease, phosphodi- and monoesterase activities. Both forms of the enzyme hydrolyzed pyrimidine homopolymers with a preference for poly U and exhibited a low specificity for purine homopolymers (poly G and poly A. RNase I acted with a 3-fold higher hydrolytic activity on poly C homopolymer than RNase IL The hydrolytic activity of both enzymes was inhibited by Zn+2, Fe+2, Cu+2 ions when yeast RNA was the substrate. The amines spermine, spermidine and tyramine at a concentration of 0.1 mM increased the enzymatic activity of both RNases by 20 to 60% of the relative activity. The hydrolytic activity of RNases I and II was stimulated by the presence of lentil lectin (LL, soybean lectin (SBA and potato lectin (STA, and inhibited by the presence of concanavalin A. The 20-200% stimulation and 40-60% inhibition depended on the proportion, on a weight basis, of enzyme to lectin and were reversible in the presence of receptor sugars.

  7. Global Autorecognition and Activation of Complement by Mannan-Binding Lectin in a Mouse Model of Type 1 Diabetes

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    Esben Axelgaard

    2017-01-01

    Full Text Available Increasing evidence links mannan-binding lectin (MBL to late vascular complications of diabetes. MBL is a complement-activating pattern recognition molecule of the innate immune system that can mediate an inflammation response through activation of the lectin pathway. In two recent animal studies, we have shown that autoreactivity of MBL is increased in the kidney in diabetic nephropathy. We hypothesize that long-term exposure to uncontrolled high blood glucose in diabetes may mediate formation of neoepitopes in several tissues and that MBL is able to recognize these structures and thus activate the lectin pathway. To test this hypothesis, we induced diabetes by injection of low-dose streptozotocin in MBL double-knockout (MBL/DKO mice. Development of diabetes was followed by measurements of blood glucose and urine albumin-to-creatinine ratio. Fluorophore-labelled recombinant MBL was injected intravenously in diabetic and nondiabetic mice followed by ex vivo imaging of several organs. We observed that MBL accumulated in the heart, liver, brain, lung, pancreas, and intestines of diabetic mice. We furthermore detected increased systemic complement activation after administration of MBL, thus indicating MBL-mediated systemic complement activation in these animals. These new findings indicate a global role of MBL during late diabetes-mediated vascular complications in various tissues.

  8. Oviposition-stimulant and ovicidal activities of Moringa oleifera lectin on Aedes aegypti.

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    Nataly Diniz de Lima Santos

    Full Text Available Natural insecticides against the vector mosquito Aedes aegypti have been the object of research due to their high level of eco-safety. The water-soluble Moringa oleifera lectin (WSMoL is a larvicidal agent against A. aegypti. This work reports the effects of WSMoL on oviposition and egg hatching of A. aegypti.WSMoL crude preparations (seed extract and 0-60 protein fraction, at 0.1 mg/mL protein concentration, did not affect oviposition, while A. aegypti gravid females laid their eggs preferentially (73% in vessels containing isolated WSMoL (0.1 mg/mL, compared with vessels containing only distilled water (control. Volatile compounds were not detected in WSMoL preparation. The hatchability of fresh eggs deposited in the solutions in the oviposition assay was evaluated. The numbers of hatched larvae in seed extract, 0-60 protein fraction and WSMoL were 45 ± 8.7 %, 20 ± 11 % and 55 ± 7.5 %, respectively, significantly (p<0.05 lower than in controls containing only distilled water (75-95%. Embryos were visualized inside fresh control eggs, but not within eggs that were laid and maintained in WSMoL solution. Ovicidal activity was also assessed using stored A. aegypti eggs. The protein concentrations able to reduce the hatching rate by 50% (EC50 were 0.32, 0.16 and 0.1 mg/mL for seed extract, 0-60 protein fraction and WSMoL, respectively. The absence of hatching of stored eggs treated with WSMoL at 0.3 mg/mL (EC99 after transfer to medium without lectin indicates that embryos within the eggs were killed by WSMoL. The reduction in hatching rate of A. aegypti was not linked to decrease in bacteria population.WSMoL acted both as a chemical stimulant cue for ovipositing females and ovicidal agent at a given concentration. The oviposition-stimulant and ovicidal activities, combined with the previously reported larvicidal activity, make WSMoL a very interesting candidate in integrated A. aegypti control.

  9. Identification of a C-type lectin with antiviral and antibacterial activity from pacific white shrimp Litopenaeus vannamei.

    Science.gov (United States)

    Li, Ming; Li, Chaozheng; Ma, Chunxia; Li, Haoyang; Zuo, Hongliang; Weng, Shaoping; Chen, Xiaohan; Zeng, Digang; He, Jianguo; Xu, Xiaopeng

    2014-10-01

    C-type lectins (CTLs) play crucial roles in innate immune responses in invertebrates by recognizing and eliminating microinvaders. In this study, a CTL from pacific white shrimp Litopenaeus vannamei (LvCTL3) was identified. LvCTL3 contains a single C-type lectin-like domain (CTLD), which shows similarities to those of other shrimp CTLs and has a mutated 'EPD' motif in Ca(2+)-binding site 2. LvCTL3 mRNA can be detected in all tested tissues and expression of LvCTL3 in gills was up-regulated after Lipopolysaccharides, poly (I:C), Vibrio parahaemolyticus and white spot syndrome virus (WSSV) challenges, suggesting activation responses of LvCTL3 to bacterial, virus and immune stimulant challenges. The 5'flanking regulatory region of LvCTL3 was cloned and we identified a NF-κB binding motif in the LvCTL3 promoter region. Dual-luciferase reporter assays indicated that over-expression of L. vannamei dorsal can dramatically up regulate the promoter activity of LvCTL3, suggesting that LvCTL3 expression could be regulated through NF-κB signaling pathway. As far as we know, this is the first report on signaling pathway involve in shrimp CTLs expression. The recombinant LvCTL3 protein was expressed in Escherichia coli and purified by Ni-affinity chromatography. The purified LvCTL3 can agglutinate Gram-negative microbe Vibrio alginolyticus and V. parahaemolyticus and Gram-positive bacteria Bacillus subtilis in the presence of calcium ions, but cannot agglutinate Gram-positive bacteria Streptococcus agalactiae. The agglutination activity of LvCTL3 was abolished when Ca(2+) was chelated with EDTA, suggesting the function of LvCTL3 is Ca(2+)-dependent. In vivo challenge experiments showed that the recombinant LvCTL3 protein can significantly reduce the mortalities of V. parahemolyticus and WSSV infection, indicating LvCTL3 might play significant roles in shrimp innate immunity defense against bacterial and viral infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Glycoprotein profiles of macrophages at different stages of activation as revealed by lectin binding after electrophoretic separation.

    Science.gov (United States)

    Irimura, T; North, S M; Nicolson, G L

    1987-01-01

    Glycoprotein profiles of rat macrophages (M phi) at different stages of activation were studied by examining the reactivity of various lectins to the glycoproteins separated by polyacrylamide gel electrophoresis. Ricinus communis agglutinin 1 (RCA1) revealed several components including glycoproteins of Mr 160 kDa and 65 kDa prominent in resident M phi. A pokeweed mitogen (PWM) isolectin, Pa-4, recognizes branched poly(N-acetyllactosamine)-type carbohydrate chains, and revealed a significant increase in glycoproteins of Mr ranging from 70 kDa to 150 kDa on thioglycolate-elicited M phi. Increased reactivity of PWM to thioglycolate-elicited M phi was observed by direct binding of 125I-labeled Pa-4 to intact or glutaraldehyde-fixed M phi. Histochemical staining of formaldehyde-fixed M phi in vitro with biotinylated Pa-4 was consistent with the gel analysis, that is, resident M phi had no reactivity while thioglycolate-elicited M phi showed slight reactivity. Alveolar and intratumoral M phi bound more Pa-4 than resident or thioglycolate-elicited M phi. The PWM isolectin may therefore serve as a marker for an early stage of M phi activation.

  11. The search for lectin isolated from the mycelial cultures of Laetiporus sulphureus

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    Grażyna Końska

    2014-08-01

    Full Text Available This study proved the presence of lectin in mycelial cultures of Laetiporus sulphureus. Lectin was excreted into the medium and its erythroagglutinating activity was not high. No active lectin was detected in hyphae using both extraction and immunofluorescence method. Comparative studies based on immunological methods indicate~ that the lectin synthesised in vitro differed from the lectin produced in fruit-bodies.

  12. Preparation of Ulex europaeus lectin-gliadin nanoparticle conjugates and their interaction with gastrointestinal mucus.

    Science.gov (United States)

    Ezpeleta, I; Arangoa, M A; Irache, J M; Stainmesse, S; Chabenat, C; Popineau, Y; Orecchioni, A M

    1999-11-25

    One approach to improve the bioavailability and efficiency of drugs consists of the association of a ligand (i.e. lectins), showing affinity for biological structures located on the mucosa surfaces, to nanoparticulate drug delivery systems. In this context, Ulex europaeus lectin-gliadin nanoparticle conjugates (UE-GNP) were prepared with the aim of evaluating their in vitro bioadhesive properties. The lectin was fixed by a covalent procedure to gliadin nanoparticles by a two-stage carbodiimide method. Typically, the amount of bound lectin was calculated to be approximately 15 microg lectin/mg nanoparticle, which represented a coupling efficiency of approximately 16% of the initial lectin concentration. In addition, the activity of these conjugates was tested with bovine submaxillary gland mucin (BSM) and the level of binding to this mucin was always much greater with UE-GNP than with controls (gliadin nanoparticles). However, the presence of 50 micromol fucose, which is the reported specific sugar for U. europaeus lectin, specifically inhibited the activity of these conjugates and, therefore, the UE-GNP binding to BSM was attenuated by 70%. These results clearly showed that the activity and specificity of U. europaeus lectin was preserved after covalent coupling to these biodegradable carriers.

  13. Expression, purification, and refolding of active recombinant human E-selectin lectin and EGF domains in Escherichia coli.

    Science.gov (United States)

    Kawano, Susumu; Iyaguchi, Daisuke; Okada, Chiaki; Sasaki, Yusuke; Toyota, Eiko

    2013-06-01

    Attempts to obtain active E-selectin from Escherichia coli (E. coli) have not yet been successful. In this study, we succeeded in expressing the recombinant lectin and epidermal growth factor domain fragments of human E-selectin (rh-ESLE) in E. coli on a large-scale. The rh-ESLE protein was expressed as an inactive form in the inclusion bodies. The inactive form of rh-ESLE was denatured and solubilized by 6 M guanidine hydrochloride and then purified by Ni(2+) affinity chromatography under denaturing conditions. Denatured rh-ESLE was then refolded by a rapid-dilution method using a large amount of refolding buffer, which contained arginine and cysteine/cystine. The refolded rh-ESLE showed binding affinity for sLe(X) (K(d) = 321 nM, B(max) = 1.9 pmol/μg protein). This result suggests that the refolded rh-ESLE recovered its native and functional structure.

  14. A mannose-specific tetrameric lectin with mitogenic and antibacterial activities from the ovary of a teleost, the cobia (Rachycentron canadum).

    Science.gov (United States)

    Ngai, Patrick H K; Ng, T B

    2007-02-01

    A tetrameric lectin, with hemagglutinating activity toward rabbit erythrocytes and with specificity toward D-mannosamine and D(+)-mannose, was isolated from the ovaries of a teleost, the cobia Rachycentron canadum. The isolation protocol comprised ion exchange chromatography on CM-cellulose and Q-Sepharose, ion exchange chromatography by fast protein liquid chromatography (FPLC) on Mono Q, and finally gel filtration by FPLC on Superose 12. The lectin was adsorbed on all ion exchangers used. It exhibited a molecular mass of 180 kDa in gel filtration on Superose 12 and a single 45-kDa band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, indicating that it is a tetrameric protein. The hemagglutinating activity of the lectin was stable up to 40 degrees C and between pH 4 and pH 10. All hemagglutinating activity disappeared at 60 degrees C and at pH 1 and pH 13. The hemagglutinating activity was doubled in the presence of 0.1 microM FeCl3. The lectin exerted antibacterial activity against Escherichia coli with 50% inhibition at 250 microg. There was no antifungal activity toward Coprinus comatus, Fusarium oxysporum, Mycosphaerella arachidicola, and Rhizoctonia solani at a dose of 300 microg. The lectin exhibited maximal mitogenic response from mouse splenocytes at a concentration of 14 microM.

  15. A Novel Lectin with Antiproliferative and HIV-1 Reverse Transcriptase Inhibitory Activities from Dried Fruiting Bodies of the Monkey Head Mushroom Hericium erinaceum

    Science.gov (United States)

    Li, Yanrui; Zhang, Guoqing; Ng, Tzi Bun; Wang, Hexiang

    2010-01-01

    A lectin designated as Hericium erinaceum agglutinin (HEA) was isolated from dried fruiting bodies of the mushroom Hericium erinaceum with a chromatographic procedure which entailed DEAE-cellulose, CM-cellulose, Q-Sepharose, and FPLC Superdex 75. Its molecular mass was estimated to be 51 kDa and its N-terminal amino acid sequences was distinctly different from those of other isolated mushroom lectins. The hemagglutinating activity of HEA was inhibited at the minimum concentration of 12.5 mM by inulin. The lectin was stable at pH 1.9–12.1 and at temperatures up to 70°C, but was inhibited by Hg2+, Cu2+, and Fe3+ ions. The lectin exhibited potent mitogenic activity toward mouse splenocytes, and demonstrated antiproliferative activity toward hepatoma (HepG2) and breast cancer (MCF7) cells with an IC50 of 56.1 μM and 76.5 μM, respectively. It manifested HIV-1 reverse transcriptase inhibitory activity with an IC50 of 31.7 μM. The lectin exhibited potent mitogenic activity toward murine splenocytes but was devoid of antifungal activity. PMID:20625408

  16. A Novel Lectin with Antiproliferative and HIV-1 Reverse Transcriptase Inhibitory Activities from Dried Fruiting Bodies of the Monkey Head Mushroom Hericium erinaceum

    Directory of Open Access Journals (Sweden)

    Yanrui Li

    2010-01-01

    Full Text Available A lectin designated as Hericium erinaceum agglutinin (HEA was isolated from dried fruiting bodies of the mushroom Hericium erinaceum with a chromatographic procedure which entailed DEAE-cellulose, CM-cellulose, Q-Sepharose, and FPLC Superdex 75. Its molecular mass was estimated to be 51 kDa and its N-terminal amino acid sequences was distinctly different from those of other isolated mushroom lectins. The hemagglutinating activity of HEA was inhibited at the minimum concentration of 12.5 mM by inulin. The lectin was stable at pH 1.9–12.1 and at temperatures up to 70∘C, but was inhibited by Hg2+, Cu2+, and Fe3+ ions. The lectin exhibited potent mitogenic activity toward mouse splenocytes, and demonstrated antiproliferative activity toward hepatoma (HepG2 and breast cancer (MCF7 cells with an IC50 of 56.1 M and 76.5 M, respectively. It manifested HIV-1 reverse transcriptase inhibitory activity with an IC50 of 31.7 M. The lectin exhibited potent mitogenic activity toward murine splenocytes but was devoid of antifungal activity.

  17. Mannan-binding lectin is involved in the protection against renal ischemia/ reperfusion injury by dietary restriction

    NARCIS (Netherlands)

    Shushimita; P. van der Pol (Pieter); R.W.F. de Bruin (Ron); J.N.M. IJzermans (Jan); C. van Kooten (Cees); F.J.M.F. Dor (Frank)

    2015-01-01

    textabstractPreoperative fasting and dietary restriction offer robust protection against renal ischemia/ reperfusion injury (I/RI) in mice.We recently showed that Mannan-binding lectin (MBL), the initiator of the lectin pathway of complement activation, plays a pivotal role in renal I/RI. Based on

  18. Targeting of macrophage galactose-type C-type lectin (MGL) induces DC signaling and activation

    DEFF Research Database (Denmark)

    Napoletano, Chiara; Zizzari, Ilaria G; Rughetti, Aurelia

    2012-01-01

    NAc or Tn)-carrying tumor-associated antigens to improve DC performance. MGL expressed by ex vivo-generated iDCs from healthy donors was engaged by a 60-mer MUC1(9Tn) -glycopeptide as a Tn-carrying tumor-associated antigen, and an anti-MGL antibody, as a specific MGL binder. We demonstrated that MGL......Dendritic cells (DCs) sense the microenvironment through several types of receptors recognizing pathogen-associated molecular patterns. In particular, C-type lectins, expressed by distinct subsets of DCs, recognize and internalize specific carbohydrate antigen in a Ca(2+) -dependent manner....... Targeting of these receptors is becoming an efficient strategy of delivering antigens in DC-based anticancer immunotherapy. Here we investigated the role of the macrophage galactose type C-lectin receptor (MGL), expressed by immature DCs (iDCs), as a molecular target for a-N-acetylgalactosamine (Gal...

  19. Broad anti-HIV activity of the Oscillatoria agardhii agglutinin homologue lectin family.

    Science.gov (United States)

    Férir, Geoffrey; Huskens, Dana; Noppen, Sam; Koharudin, Leonardus M I; Gronenborn, Angela M; Schols, Dominique

    2014-10-01

    Oscillatoria agardhii agglutinin homologue (OAAH) proteins belong to a recently discovered lectin family. The founding member OAA and a designed hybrid OAAH (OPA) recognize similar but unique carbohydrate structures of Man-9, compared with other antiviral carbohydrate-binding agents (CBAs). These two newly described CBAs were evaluated for their inactivating properties on HIV replication and transmission and for their potential as microbicides. Various cellular assays were used to determine antiviral activity against wild-type and certain CBA-resistant HIV-1 strains: (i) free HIV virion infection in human T lymphoma cell lines and PBMCs; (ii) syncytium formation assay using persistently HIV-infected T cells and non-infected CD4+ T cells; (iii) DC-SIGN-mediated viral capture; and (iv) transmission to uninfected CD4+ T cells. OAA and OPA were also evaluated for their mitogenic properties and potential synergistic effects using other CBAs. OAA and OPA inhibit HIV replication, syncytium formation between HIV-1-infected and uninfected T cells, DC-SIGN-mediated HIV-1 capture and transmission to CD4+ target T cells, thereby rendering a variety of HIV-1 and HIV-2 clinical isolates non-infectious, independent of their coreceptor use. Both CBAs competitively inhibit the binding of the Manα(1-2)Man-specific 2G12 monoclonal antibody (mAb) as shown by flow cytometry and surface plasmon resonance analysis. The HIV-1 NL4.3(2G12res), NL4.3(MVNres) and IIIB(GRFTres) strains were equally inhibited as the wild-type HIV-1 strains by these CBAs. Combination studies indicate that OAA and OPA act synergistically with Hippeastrum hybrid agglutinin, 2G12 mAb and griffithsin (GRFT), with the exception of OPA/GRFT. OAA and OPA are unique CBAs with broad-spectrum anti-HIV activity; however, further optimization will be necessary for microbicidal application. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights

  20. The mannan-binding lectin pathway of complement activation: biology and disease association

    DEFF Research Database (Denmark)

    Petersen, Steen Vang; Thiel, S; Jensenius, J C

    2001-01-01

    Mannan-binding lectin (MBL) is a plasma protein found in association with several serine proteases (MASPs) forming the MBL complex. MBL recognises carbohydrate structures arranged in a particular geometry, such as those found on the surface of micro-organisms. When bound to e.g. bacteria the MBL...... as an initiator of the host response against potential pathogenic micro-organisms. Udgivelsesdato: 2001-Aug...

  1. Comparative study of anti-angiogenic activities of luteolin, lectin and lupeol biomolecules.

    Science.gov (United States)

    Ambasta, Rashmi K; Jha, Saurabh Kumar; Kumar, Dhiraj; Sharma, Renu; Jha, Niraj Kumar; Kumar, Pravir

    2015-09-18

    Angiogenesis is a hallmark feature in the initiation, progression and growth of tumour. There are various factors for promotion of angiogenesis on one hand and on the other hand, biomolecules have been reported to inhibit cancer through anti-angiogenesis mechanism. Biomolecules, for instance, luteolin, lectin and lupeol are known to suppress cancer. This study aims to compare and evaluate the biomolecule(s) like luteolin, lupeol and lectin on CAM assay and HT-29 cell culture to understand the efficacy of these drugs. The biomolecules have been administered on CAM assay, HT-29 cell culture, cell migration assay. Furthermore, bioinformatics analysis of the identified targets of these biomolecules have been performed. Luteolin has been found to be better in inhibiting angiogenesis on CAM assay in comparison to lupeol and lectin. In line with this study when biomolecules was administered on cell migration assay via scratch assay method. We provided evidence that Luteolin was again found to be better in inhibiting HT-29 cell migration. In order to identify the target sites of luteolin for inhibition, we used software analysis for identifying the best molecular targets of luteolin. Using software analysis best target protein molecule of these biomolecules have been identified. VEGF was found to be one of the target of luteolin. Studies have found several critical point mutation in VEGF A, B and C. Hence docking analysis of all biomolecules with VEGFR have been performed. Multiple allignment result have shown that the receptors are conserved at the docking site. Therefore, it can be concluded that luteolin is not only comparatively better in inhibiting blood vessel in CAM assay, HT-29 cell proliferation and cell migration assay rather the domain of VEGFR is conserved to be targeted by luteolin, lupeol and lectin.

  2. Increased Autoreactivity of the Complement-Activating Molecule Mannan-Binding Lectin in a Type 1 Diabetes Model

    Directory of Open Access Journals (Sweden)

    Jakob Appel Østergaard

    2016-01-01

    Full Text Available Background. Diabetic kidney disease is the leading cause of end-stage renal failure despite intensive treatment of modifiable risk factors. Identification of new drug targets is therefore of paramount importance. The complement system is emerging as a potential new target. The lectin pathway of the complement system, initiated by the carbohydrate-recognition molecule mannan-binding lectin (MBL, is linked to poor kidney prognosis in diabetes. We hypothesized that MBL activates complement upon binding within the diabetic glomerulus. Methods. We investigated this by comparing complement deposition and activation in kidneys from streptozotocin-induced diabetic mice and healthy control mice. Results. After 20 weeks of diabetes, glomerular deposition of MBL was significantly increased. Diabetic animals had 2.0-fold higher (95% CI 1.6–2.5 immunofluorescence intensity from anti-MBL antibodies compared with controls (P<0.001. Diabetes and control groups did not differ in glomerular immunofluorescence intensity obtained by antibodies against complement factors C4, C3, and C9. However, the circulating complement activation product C3a was increased in diabetes as compared to control mice (P=0.04. Conclusion. 20 weeks of diabetes increased MBL autoreactivity in the kidney and circulating C3a concentration. Together with previous findings, these results indicate direct effects of MBL within the kidney in diabetes.

  3. The down-stream effects of mannan-induced lectin complement pathway activation depend quantitatively on alternative pathway amplification

    DEFF Research Database (Denmark)

    Harboe, Morten; Garred, Peter; Karlstrøm, Ellen

    2009-01-01

    Complement activation plays an important role in human pathophysiology. The effect of classical pathway activation is largely dependent on alternative pathway (AP) amplification, whereas the role of AP for the down-stream effect of mannan-induced lectin pathway (LP) activation is poorly understood...... that AP amplification is quantitatively responsible for the final effect of initial specific LP activation. TCC generation on the solid phase was distinctly but less inhibited by anti-fD. C2 bypass of the LP pathway could be demonstrated, and AP amplification was also essential during C2 bypass in LP...... as shown by complete inhibition of TCC generation in C2-deficient serum by anti-fD and anti-properdin antibodies. In conclusion, the down-stream effect of LP activation depends strongly on AP amplification in normal human serum and in the C2 bypass pathway....

  4. Lectins in human pathogenic fungi.

    Science.gov (United States)

    Gallegos, Belém; Martínez, Ruth; Pérez, Laura; Del Socorro Pina, María; Perez, Eduardo; Hernández, Pedro

    2014-01-01

    Lectins are carbohydrate-binding proteins widely distributed in nature. They constitute a highly diverse group of proteins consisting of many different protein families that are, in general, structurally unrelated. In the last few years, mushroom and other fungal lectins have attracted wide attention due to their antitumour, antiproliferative and immunomodulatory activities. The present mini-review provides concise information about recent developments in understanding lectins from human pathogenic fungi. A bibliographic search was performed in the Science Direct and PubMed databases, using the following keywords "lectin", "fungi", "human" and "pathogenic". Lectins present in fungi have been classified; however, the role played by lectins derived from human pathogenic fungi in infectious processes remains uncertain; thus, this is a scientific field requiring more research. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  5. PO-20 - Crosstalk between the lectin pathway and haemostasis in patients with pulmonary cancer

    DEFF Research Database (Denmark)

    Larsen, J B; Christensen, T D; Hvas, C L

    2016-01-01

    INTRODUCTION: Recent research has focused on the complement system in cancer, including the lectin pathway of complement activation. Mannose-binding lectin (MBL), a key activator of the lectin pathway, can bind to tumor cell surfaces in vitro, and lectin pathway activation is increased in several...

  6. Antimicrobial lectin from Schinus terebinthifolius leaf.

    Science.gov (United States)

    Gomes, F S; Procópio, T F; Napoleão, T H; Coelho, L C B B; Paiva, P M G

    2013-03-01

    Schinus terebinthifolius leaves are used for treating human diseases caused by micro-organisms. This work reports the isolation, characterization and antimicrobial activity of S. terebinthifolius leaf lectin (SteLL). The isolation procedure involved protein extraction with 0.15 mol l(-1) NaCl, filtration through activated charcoal and chromatography of the filtrate on a chitin column. SteLL is a 14-kDa glycopeptide with haemagglutinating activity that is inhibited by N-acetyl-glucosamine, not affected by ions (Ca(2+) and Mg(2+)) and stable upon heating (30-100 °C) as well as over the pH 5.0-8.0. The antimicrobial effect of SteLL was evaluated by determining the minimal inhibitory (MIC), bactericide (MBC) and fungicide (MFC) concentrations. Lectin was active against Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella enteritidis and Staphylococcus aureus. Highest bacteriostatic and bactericide effects were detected for Salm. enteritidis (MIC: 0.45 μg ml(-1)) and Staph. aureus (MBC: 7.18 μg ml(-1)), respectively. SteLL impaired the growth (MIC: 6.5 μg ml(-1)) and survival (MFC: 26 μg ml(-1)) of Candida albicans. SteLL, a chitin-binding lectin, purified in milligram quantities, showed antimicrobial activity against medically important bacteria and fungi. SteLL can be considered as a new biomaterial for potential antimicrobial applications. © 2012 The Society for Applied Microbiology.

  7. Complement activating soluble pattern recognition molecules with collagen-like regions, mannan-binding lectin, ficolins and associated proteins

    DEFF Research Database (Denmark)

    Thiel, Steffen

    2007-01-01

    Mannan-binding lectin (MBL), L-ficolin, M-ficolin and H-ficolin are all complement activating soluble pattern recognition molecules with recognition domains linked to collagen-like regions. All four may form complexes with four structurally related proteins, the three MBL-associated serine...... proteases (MASPs), MASP-1, MASP-2 and MASP-3, and a smaller MBL-associated protein (MAp19). The four recognition molecules recognize patterns of carbohydrate or acetyl-group containing ligands. After binding to the relevant targets all four are able to activate the complement system. We thus have a system...... where four different and/or overlapping patterns of microbial origin or patterns of altered-self may be recognized, but in all cases the signalling molecules, the MASPs, are shared. MASP-1 and MASP-3 are formed from one gene, MASP1/3, by alternative splicing generating two different mRNAs from a single...

  8. Venom of the Peruvian snake Bothriopsis oligolepis: Detection of antibacterial activity and involvement of proteolytic enzymes and C-type lectins in growth inhibition of Staphylococcus aureus.

    Science.gov (United States)

    Sulca, M A; Remuzgo, C; Cárdenas, J; Kiyota, S; Cheng, E; Bemquerer, M P; Machini, M T

    2017-08-01

    There is a rising interest in snake venoms proteins (SVPs) because these macromolecules are related to pharmacological properties that manifest themselves during poisoning and can lead to secondary microbial infections. Interestingly, researchers have somehow neglected the antimicrobial activity of SVPs. The aims of this study were: (i) to verify whether the venom of the Peruvian snake Bothriopsis oligolepis displays such activity; (ii) to isolate and identify some of its antimicrobial constituents. Liquid growth inhibition assays revealed that the crude venom inhibited the growth of Gram-positive and Gram-negative bacteria, but not of Candida species. Fractionation of the venom by anion-exchange chromatography provided fractions P2, P4 and P8 active against S. aureus. Fractionation of P2 or P8 by gel-filtration chromatography and of P4 by RP-HPLC furnished the sub-fractions P2-I, P8-II and P4-II, respectively, being those fractions active against S. aureus. Analyses of these sub-fractions by SDS-PAGE under denaturing/reducing conditions evidenced SVPs with 59-73, 27 and 14-28 kDa, respectively. Their in-gel tryptic digestion gave peptide fragments, whose sequencing by MALDI-TOF/MS followed by protein BLAST analysis allowed identifying PIII metalloprotease(s) [SVMP(s)] in P2-I, serine protease(s) [SVSP(s)] in P4-II and lectin(s) in P8-II. Detection of gelatinolytic activity in P2-I and P4-II reinforced the existence of PIII-SVMP(s) and SVSP(s), respectively. Activation of the coagulation cascade intrinsic pathway by P8-II (probably by interaction with factors IX and/or X as some snake C-type lectins do) supported the presence of C-type lectin(s). Altogether, these new findings reveal that the venom of the Peruvian snake Bothriopsis oligolepis displays antibacterial activity and that the isolated SVMP(s), SVSP(s) and C-type lectin(s) are associated to its ability to inhibit the growth of S. aureus. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Purification of a thermostable antinociceptive lectin isolated from Andira anthelmia.

    Science.gov (United States)

    Nascimento, Kyria Santiago; Nascimento, Francisco Lucas Faustino do; Silva, Mayara Torquato Lima; Nobre, Camila Bezerra; Moreira, Cleane Gomes; Brizeno, Luiz André Cavalcante; da Ponte, Edson Lopes; Assreuy, Ana Maria Sampaio; Cavada, Benildo Sousa

    2016-06-01

    Andira anthelmia (tribe Dalbergieae), a plant from Brazilian Amazon, possesses a seed lectin that was purified by affinity chromatography in sepharose-mannose. This novel Dalbergieae lectin, named AAL, agglutinated rabbit erythrocytes treated with trypsin. The hemagglutinating activity of AAL was maintained after incubation at a wide range of temperature (40 to 70 °C) and pH, was shown to be dependent on divalent cations, and was inhibited by d-mannose and d-sucrose. AAL showed an electrophoretic profile in sodium dodecyl sulfate-polyacrylamide gel electrophoresis similar to other lectins of the tribe Dalbergieae, presenting a double band of molecular weight with approximately 20 kDa and other minor bands of 17, 15, and 13 kDa, being the smaller fragment glycosylated. AAL injected by intravenous route in mice showed antinociceptive activity in two behavioral tests (writhing and formalin). In the writhing test induced by acetic acid, AAL showed inhibitory effect at 0.01 mg/kg (68%), 0.1 mg/kg (46%) and 1 mg/kg (74%). In the formalin test, AAL (0.1 mg/kg) inhibited by 48% the licking time in the inflammatory phase, an effect that was recovered by the lectin association with mannose. In conclusion, AAL presents analgesic effect involving the lectin domain via peripheral mechanisms of inflammatory nociception. This activity highlights the importance of lectins as tools to be used for understanding the interaction of protein-carbohydrate in processes associated to inflammatory pain. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  10. Increased activity of the mannan-binding lectin complement activation pathway in patients with colorectal cancer

    DEFF Research Database (Denmark)

    Ytting, H; Jensenius, Jens Christian; Christensen, I J

    2004-01-01

    in certain patient groups. It is hypothesized that a deficient MBL pathway might be more frequent among patients with CRC than in healthy individuals. The MBL pathway was therefore evaluated in serum obtained preoperatively from 193 patients with primary CRC and in serum from 150 healthy volunteers. METHODS......: Serum MBL concentrations and MBL/MASP activity were determined using immunofluorometric assays. The levels are presented as the median, inter-quartile range and range. RESULTS: Serum MBL levels were significantly (P ..., inter-quartile range) compared with levels in healthy blood donors (924 (230-1476) ng/mL). Similarly, the MBL/MASP activity was significantly (P age, gender, tumour location...

  11. Isolation and Biochemical Characterization of Apios Tuber Lectin

    Directory of Open Access Journals (Sweden)

    Eri Kenmochi

    2015-01-01

    Full Text Available Apios tuber lectin, named ATL, was isolated from Apios americana Medikus by two chromatography steps, hydrophobic chromatography and anion-exchange chromatography. The minimum concentration required for the hemagglutination activity toward rabbit erythrocytes of ATL was 4 μg/mL. ATL was composed of a homodimer of 28.4 kDa subunits. The amino acid sequence of ATL was similar to those of other legume lectins. The lectin showed moderate stability toward heating and acidic pH, and the binding affinity against several monosaccharides, such as D-glucosamine and D-galactosamine. ATL also bound to desialylated or agalactosylated glycoproteins such as asialo and agalacto transferrin. ATL decreased the transepithelial electrical resistance across human intestinal Caco-2 cell monolayers, suggesting the effect on the tight junction-mediated paracellular transport.

  12. Differential in vitro inhibitory activity against HIV-1 of alpha-(1-3- and alpha-(1-6-D-mannose specific plant lectins : Implication for microbicide development

    Directory of Open Access Journals (Sweden)

    Balzarini Jan

    2007-06-01

    Full Text Available Abstract Background Plant lectins such as Galanthus nivalis agglutinin (GNA and Hippeastrum hybrid agglutinin (HHA are natural proteins able to link mannose residues, and therefore inhibit HIV-target cell interactions. Plant lectins are candidate for microbicide development. Objective To evaluate the activity against HIV of the mannose-specific plant lectins HHA and GNA at the cellular membrane level of epithelial cells and monocyte-derived dendritic cells (MDDC, two potential target cells of HIV at the genital mucosal level. Methods The inhibitory effects of HHA and GNA were evaluated on HIV adsorption to genital epithelial HEC-1A cell line, on HIV transcytosis throughout a monolayer of polarized epithelial HEC-1A cells, on HIV adsorption to MDDC and on transfer of HIV from MDDC to autologous T lymphocytes. Results HHA faintly inhibited attachment to HEC-1A cells of the R5-tropic HIV-1Ba-L strain, in a dose-dependent manner, whereas GNA moderately inhibited HIV adsorption in the same context, but only at high drug doses. Only HHA, but not GNA, inhibited HIV-1JR-CSF transcytosis in a dose-dependent manner. By confocal microscopy, HHA, but not GNA, was adsorbed at the epithelial cell surface, suggesting that HHA interacts specifically with receptors mediating HIV-1 transcytosis. Both plant lectins partially inhibited HIV attachment to MDDC. HHA inhibited more efficiently the transfer of HIV from MDDC to T cell, than GNA. Both HHA and GNA lacked toxicity below 200 μg/ml irrespective the cellular system used and do not disturb the monolayer integrity of epithelial cells. Conclusion These observations demonstrate higher inhibitory activities of the lectin plant HHA by comparison to GNA, on HIV adsorption to HEC-1A cell line, HIV transcytosis through HEC-1A cell line monolayer, HIV adsorption to MDDC and HIV transfer from MDDC to T cells, highlighting the potential interest of HHA as effective microbicide against HIV.

  13. Effect of Algae and Plant Lectins on Planktonic Growth and Biofilm Formation in Clinically Relevant Bacteria and Yeasts

    Directory of Open Access Journals (Sweden)

    Mayron Alves Vasconcelos

    2014-01-01

    Full Text Available This study aimed to evaluate the abilities of plant and algae lectins to inhibit planktonic growth and biofilm formation in bacteria and yeasts. Initially, ten lectins were tested on Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella oxytoca, Pseudomonas aeruginosa, Candida albicans, and C. tropicalis at concentrations of 31.25 to 250 μg/mL. The lectins from Cratylia floribunda (CFL, Vatairea macrocarpa (VML, Bauhinia bauhinioides (BBL, Bryothamnion seaforthii (BSL, and Hypnea musciformis (HML showed activities against at least one microorganism. Biofilm formation in the presence of the lectins was also evaluated; after 24 h of incubation with the lectins, the biofilms were analyzed by quantifying the biomass (by crystal violet staining and by enumerating the viable cells (colony-forming units. The lectins reduced the biofilm biomass and/or the number of viable cells to differing degrees depending on the microorganism tested, demonstrating the different characteristics of the lectins. These findings indicate that the lectins tested in this study may be natural alternative antimicrobial agents; however, further studies are required to better elucidate the functional use of these proteins.

  14. Stability of Curcuma longa rhizome lectin: Role of N-linked glycosylation.

    Science.gov (United States)

    Biswas, Himadri; Chattopadhyaya, Rajagopal

    2016-04-01

    Curcuma longa rhizome lectin, a mannose-binding protein of non-seed portions of turmeric, is known to have antifungal, antibacterial and α-glucosidase inhibitory activities. We studied the role of complex-type glycans attached to asparagine (Asn) 66 and Asn 110 to elucidate the role of carbohydrates in lectin activity and stability. Apart from the native lectin, the characteristics of a deglycosylated Escherichia coli expressed lectin, high-mannose oligosaccharides at both asparagines and its glycosylation mutants N66Q and N110Q expressed in Pichia pastoris, were compared to understand the relationship between glycosylation and activity. Far UV circular dichroism (CD) spectra, fluorescence emission maximum, hemagglutination assay show no change in secondary or tertiary structures or sugar-binding properties between wild-type and aforementioned recombinant lectins under physiological pH. But reduced agglutination activity and loss of tertiary structure are observed in the acidic pH range for the deglycosylated and the N110Q protein. In thermal and guanidine hydrochloride (GdnCl)-induced unfolding, the wild-type and high-mannose lectins possess higher stability compared with the deglycosylated recombinant lectin and both mutants, as measured by a higher Tm of denaturation or a greater free energy change, respectively. Reversibility experiments after thermal denaturation reveal that deglycosylated proteins tend to aggregate during thermal inactivation but the wild type shows a much greater recovery to the native state upon refolding. These results suggest that N-glycosylation in turmeric lectin is important for the maintenance of its proper folding upon changes in pH, and that the oligosaccharides help in maintaining the active conformation and prevent aggregation in unfolded or partially folded molecules. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Dual recognition activity of a rhamnose-binding lectin to pathogenic bacteria and zooxanthellae in stony coral Pocillopora damicornis.

    Science.gov (United States)

    Zhou, Zhi; Yu, Xiaopeng; Tang, Jia; Zhu, Yunjie; Chen, Guangmei; Guo, Liping; Huang, Bo

    2017-05-01

    Rhamnose-binding lectin (RBL) is a type of Ca 2+ -independent lectin with tandem repeat carbohydrate-recognition domain, and is crucial for the innate immunity in many invertebrates. In this study, the cDNA sequence encoding RBL in coral Pocillopora damicornis (PdRBL-1) was cloned. The PdRBL-1 protein shared highest amino acid sequence similarity (55%) with the polyp of Hydra vulgaris, and contained a signal peptide and two tandem carbohydrate-recognition domains in which all cysteine residues were conserved. Surface plasmon resonance method revealed that the recombinant PdRBL-1 protein bound to LPS and Lipid A, but not to LTA, β-glucan, mannose and Poly (I:C). Results also showed that it bonded with zooxanthellae using western blotting method, and that the bound protein was detectable only at concentrations higher than 10 2 zooxanthellae cell mL -1 . When recombinant PdRBL-1 protein was preincubated with LPS, lower amounts of protein bound to zooxanthellae compared to cells not preincubated with LPS. Furthermore, PdRBL-1 mRNA expression increased significantly at 12 h, and declined to the baseline at 24 h after heat stress at 31 °C. These results collectively suggest that PdRBL-1 could recognize not only pathogenic bacteria but also symbiotic zooxanthellae, and that the recognition of zooxanthellae by PdRBL-1 could be repressed by pathogenic bacteria through competitive binding. This information allows us to gain new insights in the mechanisms influencing the establishment and maintenance of coral-zooxanthella symbiosis in coral P. damicornis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. A C-Type Lectin from Bothrops jararacussu Venom Disrupts Staphylococcal Biofilms

    Science.gov (United States)

    Klein, Raphael Contelli; Fabres-Klein, Mary Hellen; de Oliveira, Leandro Licursi; Feio, Renato Neves; Malouin, François; Ribon, Andréa de Oliveira Barros

    2015-01-01

    Bovine mastitis is a major threat to animal health and the dairy industry. Staphylococcus aureus is a contagious pathogen that is usually associated with persistent intramammary infections, and biofilm formation is a relevant aspect of the outcome of these infections. Several biological activities have been described for snake venoms, which led us to screen secretions of Bothrops jararacussu for antibiofilm activity against S. aureus NRS155. Crude venom was fractionated by size-exclusion chromatography, and the fractions were tested against S. aureus. Biofilm growth, but not bacterial growth, was affected by several fractions. Two fractions (15 and 16) showed the best activities and were also assayed against S. epidermidis NRS101. Fraction 15 was identified by TripleTOF mass spectrometry as a galactose-binding C-type lectin with a molecular weight of 15 kDa. The lectin was purified from the crude venom by D-galactose affinity chromatography, and only one peak was observed. This pure lectin was able to inhibit 75% and 80% of S. aureus and S. epidermidis biofilms, respectively, without affecting bacterial cell viability. The lectin also exhibited a dose-dependent inhibitory effect on both bacterial biofilms. The antibiofilm activity was confirmed using scanning electron microscopy. A pre-formed S. epidermidis biofilm was significantly disrupted by the C-type lectin in a time-dependent manner. Additionally, the lectin demonstrated the ability to inhibit biofilm formation by several mastitis pathogens, including different field strains of S. aureus, S. hyicus, S. chromogenes, Streptococcus agalactiae, and Escherichia coli. These findings reveal a new activity for C-type lectins. Studies are underway to evaluate the biological activity of these lectins in a mouse mastitis model. PMID:25811661

  17. A C-type lectin from Bothrops jararacussu venom disrupts Staphylococcal biofilms.

    Directory of Open Access Journals (Sweden)

    Raphael Contelli Klein

    Full Text Available Bovine mastitis is a major threat to animal health and the dairy industry. Staphylococcus aureus is a contagious pathogen that is usually associated with persistent intramammary infections, and biofilm formation is a relevant aspect of the outcome of these infections. Several biological activities have been described for snake venoms, which led us to screen secretions of Bothrops jararacussu for antibiofilm activity against S. aureus NRS155. Crude venom was fractionated by size-exclusion chromatography, and the fractions were tested against S. aureus. Biofilm growth, but not bacterial growth, was affected by several fractions. Two fractions (15 and 16 showed the best activities and were also assayed against S. epidermidis NRS101. Fraction 15 was identified by TripleTOF mass spectrometry as a galactose-binding C-type lectin with a molecular weight of 15 kDa. The lectin was purified from the crude venom by D-galactose affinity chromatography, and only one peak was observed. This pure lectin was able to inhibit 75% and 80% of S. aureus and S. epidermidis biofilms, respectively, without affecting bacterial cell viability. The lectin also exhibited a dose-dependent inhibitory effect on both bacterial biofilms. The antibiofilm activity was confirmed using scanning electron microscopy. A pre-formed S. epidermidis biofilm was significantly disrupted by the C-type lectin in a time-dependent manner. Additionally, the lectin demonstrated the ability to inhibit biofilm formation by several mastitis pathogens, including different field strains of S. aureus, S. hyicus, S. chromogenes, Streptococcus agalactiae, and Escherichia coli. These findings reveal a new activity for C-type lectins. Studies are underway to evaluate the biological activity of these lectins in a mouse mastitis model.

  18. Natural lectin activity in the haemolymph of Panstrogylus megistus (Heteroptera: Reduvidae Atividade lectínica na hemolinfa de Panstrongylus megistus (Heteroptera: Reduviidae

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    Y. M. Gomes

    1988-12-01

    Full Text Available The haemolymph of Panstrongylus megistus showed a natural lectin activity for a wide range of vertebrate erythocytes. Agglutination was observed against all vertebrate erythrocytes tested (human ABO, duck, rabbit, mouse, sheep, chicken and cow. Cow erythrocytes showed the lowest titre. Concerning human erythrocytes, the lectin activity was similar in the types A+,B+ and AB+ while the highest activity was observed in the type O+. Determination of minimal inhibitory concentrations was carried out with human erythrocytes type O+. Agglutination was inhibited by several carbohydrates (rhamnose. D-galatose, raffinose, D-lactose and D-fucose. Rhamnose wasreported as the strongest inhibitor (0.78mM. The results suggest the presence of more than one lection in the haemolymph of P. megistus.A hemolinfa de Panstrongylus megistus mostrou uma atividade lectínica natural para eritrócitos de vários vertebrados e não mostrou especificidade para os diversos tipos de eritrócitos testados (humano ABO, pato, coelho,c amundongo,carneiro, galinha e boi. Com relação aos eritrócitos humanos a atividade lectínica foi similar nos tipos A+, B+ e AB+ enquanto a atividade mais alta foi observada no tipo O+. O título de aglutinação entre eritrócitos animais não mostrou diferença apreciável, excluindo eritrócitos de boi, que apresentaram o título mmais baixo. A determinação da concentração mínima de inibição foi realizada com eritrócitos humanos O+. A aglutinação foi inibida por vários carboidratos (ramnose, D-dalactose, rafinose, D-lactose e D-fucose. A ramnose foi o inibidor mais potente (0,78 mM. Os resultados sugerem a presença de mais de uma lectina na hemolinfa de P. megistus.

  19. Lectin, hemolysin and protease inhibitors in seed fractions with ovicidal activity against Haemonchus contortus.

    Science.gov (United States)

    Salles, Hévila Oliveira; Braga, Ana Carolina Linhares; Nascimento, Maria Thayana dos Santos Canuto do; Sousa, Ana Márjory Paiva; Lima, Adriano Rodrigues; Vieira, Luiz da Silva; Cavalcante, Antônio Cézar Rocha; Egito, Antonio Silvio do; Andrade, Lúcia Betânia da Silva

    2014-01-01

    Bioactive molecules of plant species are promising alternatives for the chemical control of gastrointestinal nematodes in ruminants. Extracts of native and exotic seed species from Brazil's semi-arid region were tested in vitro in an egg hatch assay and the bioactivity of their proteins was investigated. Each seed species was subjected to three extractions with three types of solvents. All the seeds showed ovicidal activity, which varied according to the solvents. Higher ovicidal activity was found in the molecule fractions of low molecular weight (Albizia lebbeck, Ipomoea asarifolia, Jatropha curcas, Libidibia ferrea, Moringa oleifera and Ricinus communis (P0.05, Bonferroni test). Hemagglutinating activity was detected in the fractions of C. spectabilis and M. oleifera fractions, hemolysin activity in the A. lebbeck and M. oleifera fractions, serine protease inhibitory activity in the A. lebbeck, I. asarifolia, J. curcas, M. oleifera and R. communis fractions, cysteine protease inhibitor activity in the M. oleifera fraction, and no protein activity in the L. ferrea fraction. The results of this work reveal new plant species with a potential for use in controlling nematode parasites in goats, thus opening a new field of research involving plant protein molecules with ovicidal properties.

  20. Lectin, hemolysin and protease inhibitors in seed fractions with ovicidal activity against Haemonchus contortus

    Directory of Open Access Journals (Sweden)

    Hévila Oliveira Salles

    Full Text Available Bioactive molecules of plant species are promising alternatives for the chemical control of gastrointestinal nematodes in ruminants. Extracts of native and exotic seed species from Brazil's semi-arid region were tested in vitro in an egg hatch assay and the bioactivity of their proteins was investigated. Each seed species was subjected to three extractions with three types of solvents. All the seeds showed ovicidal activity, which varied according to the solvents. Higher ovicidal activity was found in the molecule fractions of low molecular weight (0.05, Bonferroni test. Hemagglutinating activity was detected in the fractions of C. spectabilis and M. oleifera fractions, hemolysin activity in the A. lebbeck and M. oleifera fractions, serine protease inhibitory activity in the A. lebbeck, I. asarifolia, J. curcas, M. oleifera and R. communis fractions, cysteine protease inhibitor activity in the M. oleifera fraction, and no protein activity in the L. ferrea fraction. The results of this work reveal new plant species with a potential for use in controlling nematode parasites in goats, thus opening a new field of research involving plant protein molecules with ovicidal properties.

  1. Effect of Lectins from Diocleinae Subtribe against Oral Streptococci

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    Edson Holanda Teixeira

    2011-04-01

    Full Text Available Surface colonization is an essential step in biofilm development. The ability of oral pathogens to adhere to tooth surfaces is directly linked with the presence of specific molecules at the bacterial surface that can interact with enamel acquired pellicle ligands. In light of this, the aim of this study was to verify inhibitory and antibiofilm action of lectins from the Diocleinaesubtribe against Streptococcus mutans and Streptococcus oralis. The inhibitory action against planctonic cells was assessed using lectins from Canavaliaensi formis (ConA, Canavalia brasiliensis (ConBr, Canavalia maritima (ConM, Canavalia gladiata (CGL and Canavalia boliviana (ConBol. ConBol, ConBr and ConM showed inhibitory activity on S. mutans growth. All lectins, except ConA, stimulated significantly the growth of S. oralis. To evaluate the effect on biofilm formation, clarified saliva was added to 96-well, flat-bottomed polystyrene plates, followed by the addition of solutions containing 100 or 200 µg/mL of the selected lectins. ConBol, ConM and ConA inhibited the S. mutans biofilms. No effects were found on S. oralis biofilms. Structure/function analysis were carried out using bioinformatics tools. The aperture and deepness of the CRD (Carbohydrate Recognition Domain permit us to distinguish the two groups of Canavalia lectins in accordance to their actions against S. mutans and S. oralis. The results found provide a basis for encouraging the use of plant lectins as biotechnological tools in ecological control and prevention of caries disease.

  2. Quantitative analysis of receptor-mediated uptake and pro-apoptotic activity of mistletoe lectin-1 by high content imaging.

    Science.gov (United States)

    Beztsinna, N; de Matos, M B C; Walther, J; Heyder, C; Hildebrandt, E; Leneweit, G; Mastrobattista, E; Kok, R J

    2018-02-09

    Ribosome inactivating proteins (RIPs) are highly potent cytotoxins that have potential as anticancer therapeutics. Mistletoe lectin 1 (ML1) is a heterodimeric cytotoxic protein isolated from European Mistletoe and belongs to RIP class II. The aim of this project was to systematically study ML1 cell binding, endocytosis pathway(s), subcellular processing and apoptosis activation. For this purpose, state of the art cell imaging equipment and automated image analysis algorithms were used. ML1 displayed very fast binding to sugar residues on the membrane and energy-dependent uptake in CT26 cells. The co-staining with specific antibodies and uptake blocking experiments revealed involvement of both clathrin-dependent and -independent pathways in ML1 endocytosis. Co-localization studies demonstrated the toxin transport from early endocytic vesicles to Golgi network; a retrograde road to the endoplasmic reticulum. The pro-apoptotic and antiproliferative activity of ML1 were shown in time lapse movies and subsequently quantified. ML1 cytotoxicity was less affected in multidrug resistant tumor cell line 4T1 in contrast to commonly used chemotherapeutic drug (ML1 resistance index 6.9 vs 13.4 for doxorubicin; IC 50 : ML1 1.4 ng/ml vs doxorubicin 24000 ng/ml). This opens new opportunities for the use of ML1 as an alternative treatment in multidrug resistant cancers.

  3. The Emerging Role of Complement Lectin Pathway in Trypanosomatids: Molecular Bases in Activation, Genetic Deficiencies, Susceptibility to Infection, and Complement System-Based Therapeutics

    Directory of Open Access Journals (Sweden)

    Ingrid Evans-Osses

    2013-01-01

    Full Text Available The innate immune system is evolutionary and ancient and is the pivotal line of the host defense system to protect against invading pathogens and abnormal self-derived components. Cellular and molecular components are involved in recognition and effector mechanisms for a successful innate immune response. The complement lectin pathway (CLP was discovered in 1990. These new components at the complement world are very efficient. Mannan-binding lectin (MBL and ficolin not only recognize many molecular patterns of pathogens rapidly to activate complement but also display several strategies to evade innate immunity. Many studies have shown a relation between the deficit of complement factors and susceptibility to infection. The recently discovered CLP was shown to be important in host defense against protozoan microbes. Although the recognition of pathogen-associated molecular patterns by MBL and Ficolins reveal efficient complement activations, an increase in deficiency of complement factors and diversity of parasite strategies of immune evasion demonstrate the unsuccessful effort to control the infection. In the present paper, we will discuss basic aspects of complement activation, the structure of the lectin pathway components, genetic deficiency of complement factors, and new therapeutic opportunities to target the complement system to control infection.

  4. Mushroom Lectins: Specificity, Structure and Bioactivity Relevant to Human Disease

    Directory of Open Access Journals (Sweden)

    Mohamed Ali Abol Hassan

    2015-04-01

    Full Text Available Lectins are non-immunoglobulin proteins that bind diverse sugar structures with a high degree of selectivity. Lectins play crucial role in various biological processes such as cellular signaling, scavenging of glycoproteins from the circulatory system, cell–cell interactions in the immune system, differentiation and protein targeting to cellular compartments, as well as in host defence mechanisms, inflammation, and cancer. Among all the sources of lectins, plants have been most extensively studied. However, more recently fungal lectins have attracted considerable attention due to their antitumor, antiproliferative and immunomodulatory activities. Given that only 10% of mushroom species are known and have been taxonomically classified, mushrooms represent an enormous unexplored source of potentially useful and novel lectins. In this review we provide an up-to-date summary on the biochemical, molecular and structural properties of mushroom lectins, as well as their versatile applications specifically focusing on mushroom lectin bioactivity.

  5. Recombinant protein expression of Moringa oleifera lectin in methylotrophic yeast as active coagulant for sustainable high turbid water treatment.

    Science.gov (United States)

    Abd Wahid, Muhamad Azhar; Megat Mohd Noor, Megat Johari; Goto, Masafumi; Sugiura, Norio; Othman, Nor'azizi; Zakaria, Zuriati; Ahmad Mohammed, Thamer; Jusoh, Ahmad; Hara, Hirofumi

    2017-08-01

    The natural coagulant Moringa oleifera lectin (MoL) as cationic protein is a promising candidate in coagulation process of water treatment plant. Introducing the gene encoding MoL into a host, Pichia pastoris, to secrete soluble recombinant protein is assessed in this study. Initial screening using PCR confirmed the insertion of MoL gene, and SDS-PAGE analysis detected the MoL protein at 8 kDa. Cultured optimization showed the highest MoL protein at 520 mg/L was observed at 28 °C for 144 h of culturing by induction in 1% methanol. Approximately, 0.40 mg/mL of recombinant MoL protein showed 95 ± 2% turbidity removal of 1% kaolin suspension. In 0.1% kaolin suspension, the concentration of MoL at 10 μg/mL exhibits the highest turbidity reduction at 68 ± 1%. Thus, recombinant MoL protein from P. pastoris is an effective coagulant for water treatment.

  6. ABH antigens as recognition sites for the activation of red blood cell anion exchange by the lectin ulex europaeus agglutinin I.

    Science.gov (United States)

    Engelmann, B

    1993-11-01

    The blood group antigen H (blood group O) and fucose-specific lectin Ulex europaeus agglutinin I (UEA1) (10 micrograms/ml) was found to increase the rate constant of Cl- efflux into 100 mM Na+ oxalate media by about 40% in erythrocytes taken from antigen H donors. In 100 mM K+ oxalate, 150 mM Na+ pyruvate and in 150 mM Na+ acetate media the lectin elevated the rate constant of Cl- efflux by 20-50%. The acceleration of Cl- efflux by UEA1 was completely blocked by 10 microM 4,4'-diisothiocyanato-stilbene-2,2'-disulfonic acid (DIDS) indicating that the effect of the lectin is mediated by the anion exchanger of human erythrocytes (band 3 protein). In antigen A1 erythrocytes no significant stimulation of anion exchange by UEA1 was seen. The activation of Cl- efflux was completely prevented by addition of 1 mM fucose to the medium. These results suggest that the effect of UEA1 is mediated through interaction with the fucose residues of H antigens. Increasing extracellular Ca++ from 0.5 to 5 mM in Na+ pyruvate or Na+ acetate media slightly reduced the acceleration of anion exchange by the lectin. On the other hand, replacing part of extracellular chloride by bicarbonate did not considerably alter the (previously reported) stimulatory effect of UEA1 on red blood cell Ca++ uptake. This suggests that the acceleration of anion exchange and of Ca++ uptake by UEA1, respectively, are mediated by different mechanisms. It is concluded that UEA1 activates anion exchange of human erythrocytes most probably by a direct interaction with H antigens present on extracellular domains of the band 3 protein.

  7. [Lectins, adhesins, and lectin-like substances of lactobacilli and bifidobacteria].

    Science.gov (United States)

    Lakhtin, V M; Aleshkin, V A; Lakhtin, M V; Afanas'ev, S S; Pospelova, V V; Shenderov, B A

    2006-01-01

    Cell-surface adhesion factors of lactobacilli and bifidobacteria, such as lectin/adhesin proteins of S-layers, secreted lectin-like bacteriocins, and lectin-like complexes, are considered and classified in the article. Certain general and specific properties of these factors are noted, such as in vitro and in vivo adhesion, cell co(aggregation), participation in the forming of microbial biofilms and colonization of mammalian alimentary tract, as well as complexation with biopolymers and bioeffectors, specificity to glycanes and natural glycoconjugates, domain and spatial organization of adhesion factors, co-functioning with other cytokines (pro- and anti-inflammatory ones), regulation of target cell properties, and other biological and physiological activities. The authors also note possibilities of application of lectins and lectin-like proteins of probiotic strains of lactobacilli and bifidobacteria in medicine and biotechnology.

  8. Isolation and Molecular Characterization of Two Lectins from Dwarf Elder (Sambucus ebulus L. Blossoms Related to the Sam n1 Allergen

    Directory of Open Access Journals (Sweden)

    Tomas Girbes

    2013-10-01

    Full Text Available Sambucus species contain a number of lectins with and without antiribosomal activity. Here, we show that dwarf elder (Sambucus ebulus L. blossoms express two D-galactose-binding lectins that were isolated and purified by affinity chromatography and gel filtration. These proteins, which we named ebulin blo (A-B toxin and SELblo (B-B lectin—blo from blossoms—were subjected to molecular characterization and analysis by MALDI-TOF mass spectrometry and tryptic peptide fingerprinting. Both lectins share a high degree of amino acid sequence homology with Sambucus lectins related to the Sam n1 allergen. Ebulin blo, but not SELblo, was highly toxic by nasal instillation to mice. Overall, our results suggested that both lectins would belong to an allergen family exemplified by Sam n1 and could trigger allergy responses. Furthermore, they raise a concern about ebulin blo toxicity.

  9. Differential effect of plant lectins on mast cells of different origins

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    F.C. Lopes

    2005-06-01

    Full Text Available Histamine release induced by plant lectins was studied with emphasis on the carbohydrate specificity, external calcium requirement, metal binding sites, and mast cell heterogeneity and on the importance of antibodies bound to the mast cell membrane to the lectin effect. Peritoneal mast cells were obtained by direct lavage of the rat peritoneal cavity and guinea pig intestine and hamster cheek pouch mast cells were obtained by dispersion with collagenase type IA. Histamine release was induced with concanavalin A (Con A, lectins from Canavalia brasiliensis, mannose-specific Cymbosema roseum, Maackia amurensis, Parkia platycephala, Triticum vulgaris (WGA, and demetallized Con A and C. brasiliensis, using 1-300 µg/ml lectin concentrations applied to Wistar rat peritoneal mast cells, peaking on 26.9, 21.0, 29.1, 24.9, 17.2, 10.7, 19.9, and 41.5%, respectively. This effect was inhibited in the absence of extracellular calcium. The lectins were also active on hamster cheek pouch mast cells (except demetallized Con A and on Rowett nude rat (animal free of immunoglobulins peritoneal mast cells (except for mannose-specific C. roseum, P. platycephala and WGA. No effect was observed in guinea pig intestine mast cells. Glucose-saturated Con A and C. brasiliensis also released histamine from Wistar rat peritoneal mast cells. These results suggest that histamine release induced by lectins is influenced by the heterogeneity of mast cells and depends on extracellular calcium. The results also suggest that this histamine release might occur by alternative mechanisms, because the usual mechanism of lectins is related to their binding properties to metals from which depend the binding to sugars, which would be their sites to bind to immunoglobulins. In the present study, we show that the histamine release by lectins was also induced by demetallized lectins and by sugar-saturated lectins (which would avoid their binding to other sugars. Additionally, the lectins

  10. Separation and Enrichment of Lectin from Zihua Snap-Bean (Phaseolus vulgaris Seeds by PEG 600–Ammonium Sulfate Aqueous Two-Phase System

    Directory of Open Access Journals (Sweden)

    Bin Jiang

    2017-09-01

    Full Text Available A fast and efficient method based on a polyethylene glycol (PEG 600/(NH42SO4 aqueous two-phase system for extracting lectin from Zihua snap-bean (Phaseolus vulgaris seeds was established. According to a Box–Behnken design (BBD, involving four factors at three levels each subjected to analysis of variance (ANOVA and response surface analysis, the protein recovery and the purification factor of lectin in the top phase were used as the response values of the variance analysis to acquire the multivariate quadratic regression model. SDS–PAGE electrophoresis and the hemagglutination test were used to detect the distribution of lectin in the aqueous two-phase system (ATPS. The obtained data indicated that lectin was preferentially partitioned into the PEG-rich phase, and the ATPS, composed of 15% (NH42SO4 (w/w, 18% PEG 600 (w/w, 0.4 g/5 g NaCl and 1 mL crude extract, showed good selectivity for lectin when the pH value was 7.5. Under the optimal conditions, most of the lectin was assigned to the top phase in the ATPS, and the hemagglutination activity of the purified lectin in the top phase was 3.08 times that of the crude extract. Consequently, the PEG 600/(NH42SO4 aqueous two-phase system was an effective method for separating and enriching lectin directly from the crude extract of Zihua snap-bean seeds.

  11. An acetylation site in lectin domain modulates the biological activity of polypeptide GalNAc-transferase-2

    DEFF Research Database (Denmark)

    Zlocowski, Natacha; Lorenz, Virginia; Bennett, Eric Paul

    2013-01-01

    Abstract Polypeptide GalNAc-transferases (ppGalNAc-Ts) are a family of enzymes that catalyze the initiation of mucin-type O-glycosylation. All ppGalNAc-T family members contain a common (QXW)3 motif which is present in R-type lectin group. Acetylation site K521 is part of the QKW motif of ß......-trefoil in the lectin domain of ppGalNAc-T2. We used a combination of acetylation and site-directed mutagenesis approaches to examine the functional role of K521 in ppGalNAc-T2. Binding assays of non-acetylated and acetylated forms of the mutant ppGalNAc-T2K521Q to various naked and aGalNAc-glycosylated mucin peptides...... indicated that degree of interaction of lectin domain with aGalNAc depends on the peptide sequence of mucin. Studies of inhibitory effect of various carbohydrates on interactions of ppGalNAc-T2 with MUC1aGalNAc indicate that point K521Q mutation enhance the carbohydrate specificity of lectin domain for aGalNAc...

  12. Lectin-Array Blotting.

    Science.gov (United States)

    Pazos, Raquel; Echevarria, Juan; Hernandez, Alvaro; Reichardt, Niels-Christian

    2017-09-01

    Aberrant protein glycosylation is a hallmark of cancer, infectious diseases, and autoimmune or neurodegenerative disorders. Unlocking the potential of glycans as disease markers will require rapid and unbiased glycoproteomics methods for glycan biomarker discovery. The present method is a facile and rapid protocol for qualitative analysis of protein glycosylation in complex biological mixtures. While traditional lectin arrays only provide an average signal for the glycans in the mixture, which is usually dominated by the most abundant proteins, our method provides individual lectin binding profiles for all proteins separated in the gel electrophoresis step. Proteins do not have to be excised from the gel for subsequent analysis via the lectin array but are transferred by contact diffusion from the gel to a glass slide presenting multiple copies of printed lectin arrays. Fluorescently marked glycoproteins are trapped by the printed lectins via specific carbohydrate-lectin interactions and after a washing step their binding profile with up to 20 lectin probes is analyzed with a fluorescent scanner. The method produces the equivalent of 20 lectin blots in a single experiment, giving detailed insight into the binding epitopes present in the fractionated proteins. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  13. An assay for the mannan-binding lectin pathway of complement activation

    DEFF Research Database (Denmark)

    Petersen, Steen Vang; Thiel, S; Jensen, L

    2001-01-01

    activation. Therefore, in a generally applicable complement activation assay specific for the MBL pathway, the activity of the classical pathway must be inhibited. This can be accomplished by exploiting the finding that high ionic strength buffers inhibit the binding of C1q to immune complexes and disrupt...

  14. T-antigen binding lectin with antibacterial activity from marine invertebrate, sea cucumber (Holothuria scabra): Possible involvement in differential recognition of bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Gowda, N.M.; Goswami, U.; Khan, M.I.

    report a study of a lectin (HSL) involved in immune response in the echinoderm, sea cucumber (Holothuria scabra). Correlative studies indicate that the expression of this defensive lectin is induced by bacterial challenge, wherein cell wall...

  15. Cyborg lectins: novel leguminous lectins with unique specificities.

    Science.gov (United States)

    Yamamoto, K; Maruyama, I N; Osawa, T

    2000-01-01

    Bauhinia purpurea lectin (BPA) is one of the beta-galactose-binding leguminous lectins. Leguminous lectins contain a long metal-binding loop, part of which determines their carbohydrate-binding specificities. Random mutations were introduced into a portion of the cDNA coding BPA that corresponds to the carbohydrate-binding loop of the lectin. An library of the mutant lectin expressed on the surface of lambda foo phages was screened by the panning method. Several phage clones with an affinity for mannose or N-acetylglucosamine were isolated. These results indicate the possibility of making artificial lectins (so-called "cyborg lectins") with distinct and desired carbohydrate-binding specificities.

  16. Lessons learned from mice deficient in lectin complement pathway molecules

    DEFF Research Database (Denmark)

    Genster, Ninette; Takahashi, Minoru; Sekine, Hideharu

    2014-01-01

    in turn activate downstream complement components, ultimately leading to elimination of the pathogen. Mice deficient in the key molecules of lectin pathway of complement have been generated in order to build knowledge of the molecular mechanisms of the lectin pathway in health and disease. Despite......The lectin pathway of the complement system is initiated when the pattern-recognition molecules, mannose-binding lectin (MBL), ficolins or collectin-11, bind to invading pathogens or damaged host cells. This leads to activation of MBL/ficolin/collectin-11 associated serine proteases (MASPs), which...... differences in the genetic arrangements of murine and human orthologues of lectin pathway molecules, the knockout mice have proven to be valuable models to explore the effect of deficiency states in humans. In addition, new insight and unexpected findings on the diverse roles of lectin pathway molecules...

  17. In vivo and in vitro antibacterial activity of conglutinin, a mammalian plasma lectin

    DEFF Research Database (Denmark)

    Friis-Christiansen, P; Thiel, S; Svehag, S E

    1990-01-01

    of BALB/c mice with Salmonella typhimurium is mediated by conglutinin. Conglutinin also demonstrated antibacterial activity against E. coli and S. typhimurium in vitro. The expression of this activity required the presence of heat-labile serum factors and peritoneal exudate or spleen cells...

  18. Chitovibrin: a chitin-binding lectin from Vibrio parahemolyticus.

    Science.gov (United States)

    Gildemeister, O S; Zhu, B C; Laine, R A

    1994-12-01

    A novel 134 kDa, calcium-independent chitin-binding lectin, 'chitovibrin', is secreted by the marine bacterium Vibrio parahemolyticus, inducible with chitin or chitin-oligomers. Chitovibrin shows no apparent enzymatic activity but exhibits a strong affinity for chitin and chito-oligomers > dp9. The protein has an isoelectric pH of 3.6, shows thermal tolerance, binds chitin with an optimum at pH 6 and is active in 0-4 M NaCl. Chitovibrin appears to be completely different from other reported Vibrio lectins and may function to bind V. parahemolyticus to chitin substrates, or to capture or sequester chito-oligomers. It may be a member of a large group of recently described proteins in Vibrios related to a complex chitinoclastic (chitinivorous) system.

  19. Depressed activation of the lectin pathway of complement in hereditary angioedema

    DEFF Research Database (Denmark)

    Varga, L; Széplaki, G; Laki, J

    2008-01-01

    ) in three complement activation pathways. Functional activity of the CP, LP and AP were measured in the sera of 68 adult patients with hereditary angioedema (HAE) and 64 healthy controls. In addition, the level of C1q, MBL, MBL-associated serine protease-2 (MASP-2), C4-, C3- and C1INH was measured...... by standard laboratory methods. MBL-2 genotypes were determined by polymerase chain reaction. Besides the complement alterations (low CP and C1INH activity, low C4-, C1INH concentrations), which characterize HAE, the level of MASP-2 was also lower (P = 0.0001) in patients compared with controls. Depressed LP...

  20. [Separation of osteoclasts by lectin affinity chromatography].

    Science.gov (United States)

    Itokazu, M; Tan, A; Tanaka, S

    1991-09-01

    Newborn rat calvaria bone cells obtained by digestion were fractionated on columns of wheat-germ agglutinin (WGA) sepharose 6MB for osteoclast isolation. The initial nonspecific binding cells which were passed through the WGA sepharose column by a buffer acquired a high enzyme activity of alkaline phosphatase, but not that of acid phosphatase. However, elution of cells using a buffer with the addition of N-acetyl-D-glucosamine resulted in a high acid phosphatase activity but no alkaline phosphatase activity. The former WGA binding negative fraction enriched osteoblasts averaging 30 microns in size. The latter WGA binding positive fraction enriched osteoclasts ranging from 20 microns to 60 microns in size. The electron-microscope clearly demonstrated the cellular details of osteoclasts. Isolated cell counts showed a ratio of six to four. These results indicate that our method of osteoclast isolation is simple and useful in lectin affinity chromatography because all cells have sugar moieties on their surface and the binding of osteoclasts can be reversed by the addition of specific lectin-binding sugars to the eluting buffer.

  1. Lectin typing of Campylobacter concisus

    DEFF Research Database (Denmark)

    Aabenhus, Rune Munck; Hynes, Sean O; Permin, Henrik

    2002-01-01

    A total of 44 clinical isolates and the type strain of the putative pathogen Campylobacter concisus were grouped based on their reactions with plant lectins. The optimized lectin typing system used C. concisus strains proteolytically pretreated and subsequently typed by using a panel of four...... lectins. The system grouped all 45 strains into 13 lectin reaction patterns, leaving no strain untypeable due to autoagglutination. Lectin types were both stable and reproducible....

  2. Atividades biológicas das lectinas PHA, WGA, jacalina e artocarpina Biological activities of PHA, WGA, jacalin and artocarpin lectins

    Directory of Open Access Journals (Sweden)

    Ana Maria Sell

    2000-05-01

    Full Text Available As lectinas são (glicoproteínas que se ligam a açúcares. O interesse destas moléculas na investigação científica se deve às diversas atividades biológicas a elas atribuídas. Além da identificação de grupos sangüíneos, da caracterização de microorganismos e da estimulação mitogênica de células imunes, as lectinas estão envolvidas nos processos de reconhecimento e das interações celulares. No presente trabalho, revisamos algumas atividades biológicas das lectinas PHA (fitohemaglutinina de Phaseolus vulgaris, WGA (aglutinina de germe de trigo, jacalina e artocarpina (lectinas de Artocarpus integrifolia. PHA, jacalina e artocarpina são mitogênicas para os linfócitos, estimulam a produção de citocinas endógenas, a atração e a ativação de leucócitos. WGA é uma lectina não-mitogênica, no entanto, modula a resposta de defesa estimulando a liberação de superóxido pelos neutrófilos. O entendimento das atividades biológicas permitirá o uso destas moléculas como uma ferramenta útil no diagnóstico e tratamento de muitas doenças.Lectins are ubiquitous (glycoproteins, which exhibit a specific and reversibly carbohydrate binding activity. Because of their structural complexity and variability, they can participate in many physiological functions. Besides the blood groups identification, microorganism characterization and mitogenic immune cell proliferation, they are involved in the cell recognition and cell-cell interaction. In the present work we revised some biological activities of the PHA (Phaseolus vulgaris phytohemagglutinin, WGA (wheat germ agglutinin, jacalin and artocarpin (Artocarpus integrifolia lectins. PHA, jacalin and artocarpin may stimulate lymphocyte proliferation, attract and activate mononuclear cells and stimulate endogenous citokines production. WGA is a nonmitogenic lectin, however it may stimulate neutrophil superoxide production. The understanding of the lectin biological activities may

  3. A unique epidermal mucus lectin identified from catfish (Silurus asotus): first evidence of intelectin in fish skin slime.

    Science.gov (United States)

    Tsutsui, Shigeyuki; Komatsu, Yukie; Sugiura, Takaya; Araki, Kyosuke; Nakamura, Osamu

    2011-11-01

    The present study reports a new type of skin mucus lectin found in catfish Silurus asotus. The lectin exhibited calcium-dependent mannose-binding activity. When mannose eluate from chromatography with mannose-conjugated agarose was analysed by SDS-PAGE, the lectin appeared as a single 35-kDa band. Gel filtration showed that the lectin forms monomers and dimers. A 1216-bp cDNA sequence obtained by RACE-PCR from the skin encoded a 308 amino acid secretory protein with homology to mammalian and fish intelectins. RT-PCR demonstrated that the lectin gene was expressed in the gill, kidney and skin. Subsequent sequencing revealed the presence of an isoform in the gills. Antiserum detected the intelectin protein in club cells in the skin and gill, renal tubules and blood plasma. Although intelectin gene expression was not induced by in vivo bacterial stimulation, the intelectin showed agglutination activity against the pathogenic bacterium Aeromonas salmonicida, suggesting that the lectin plays an important role in self-defence against bacteria in the skin surface of the catfish. These findings represent one of the few examples of characterization and functional analysis of a fish intelectin protein.

  4. Effects of indian coral tree, Erythrina indica lectin on eggs and larval development of melon fruit fly, Bactrocera cucurbitae.

    Science.gov (United States)

    Singh, Kuljinder; Kaur, Manpreet; Rup, Pushpinder J; Singh, Jatinder

    2009-07-01

    Present study was undertaken to investigate the influence of D-galactose binding lectin from Erythrina indica Lam. on the eggs and second instar larvae (64-72 hr) of melon fruit fly, Bactrocera cucurbitae (Coquillett). The lectin from E. indica seeds was extracted and purified by affinity chromatography using asilofetuin linked porous amino activated silica beads. The effects of various concentrations (0, 125, 250, 500 and 1000 microg ml(-1)) of lectin were studied on freshly laid eggs (0-8 hr) of B. cucurbitae which showed non-significant reduction in percent hatching of eggs. However, the treatment of second instar larvae (64-72 hr) with various test concentrations (0, 25, 50, 100 and 200 microg ml(-1)) of lectin significantly reduced the percent pupation and percent emergence of B. cucurbitae depicting a negative correlation with the lectin concentration. The LC50 (81 microg ml(-1)) treatment significantly decreased the pupal weight. Moreover, the treatment of larvae had also induced a significant increase in the remaining development duration. The activity of three hydrolase enzymes (esterases, acid and alkaline phosphatases), one oxidoreductase (catalase) and one group transfer enzyme (glutathione S-transferases) was assayed in second instar larvae under the influence of LC50 concentration of lectin for three exposure intervals (24, 48 and 72 hr). It significantly suppressed the activity of all the enzymes after all the three exposure intervals except for esterases which increased significantly.

  5. Two Dimensional Electrophoresis of Galactosidase Relating to the Disappearance of Bombyx Lectin Activity

    OpenAIRE

    カトウ, ヤスオ; Yasuo, Kato

    2004-01-01

    "Two dimensional polyacrylamide gel electroporesis (2 D-PAGE) analysis on the haemolymph of Bombyx mori was performed using the Mini-PROTEAN mini tube gel two dimensional polyacrylamide gel electrophoresis system (Bio-Rad Laboratories, Inc.). The result on various electrophoretical conditions using the haemolymph-protein showed the possibility that the haemolymph-protein was separated actually by means of this method. Moreover, the result of 2 D-PAGE analysis on Fraction II obtained by gel fi...

  6. Mannose-binding lectin genetics: from A to Z

    DEFF Research Database (Denmark)

    Garred, Peter

    2008-01-01

    MBL (mannose-binding lectin) is primarily a liver-derived collagen-like serum protein. It binds sugar structures on micro-organisms and on dying host cells and is one of the four known mediators that initiate activation of the complement system via the lectin pathway. Common variant alleles situa...

  7. Recombinant production of plant lectins in microbial systems for biomedical application – the frutalin case study

    Directory of Open Access Journals (Sweden)

    Carla eOliveira

    2014-08-01

    Full Text Available Frutalin is a homotetrameric partly-glycosylated alpha-D-galactose-binding lectin of biomedical interest from Artocarpus incisa (breadfruit seeds, belonging to the jacalin-related lectins family. As other plant lectins, frutalin is a heterogeneous mixture of several isoforms possibly with distinct biological activities. The main problem of using such lectins as biomedical tools is that batch-to-batch variation in isoforms content may lead to inconstant results. The production of lectins by recombinant means has the advantage of obtaining high amounts of proteins with defined amino-acid sequences and more precise properties. In this mini review, we provide the strategies followed to produce two different forms of frutalin in two different microbial systems: Escherichia coli and Pichia pastoris. The processing and functional properties of the recombinant frutalin obtained from these hosts are compared to those of frutalin extracted from breadfruit. Emphasis is given particularly to recombinant frutalin produced in P. pastoris, which showed a remarkable capacity as biomarker of human prostate cancer and as apoptosis-inducer of cancer cells. Recombinant frutalin production opens perspectives for its development as a new tool in human medicine.

  8. Recombinant production of plant lectins in microbial systems for biomedical application – the frutalin case study

    Science.gov (United States)

    Oliveira, Carla; Teixeira, José A.; Domingues, Lucília

    2014-01-01

    Frutalin is a homotetrameric partly glycosylated α-D-galactose-binding lectin of biomedical interest from Artocarpus incisa (breadfruit) seeds, belonging to the jacalin-related lectins family. As other plant lectins, frutalin is a heterogeneous mixture of several isoforms possibly with distinct biological activities. The main problem of using such lectins as biomedical tools is that “batch-to-batch” variation in isoforms content may lead to inconstant results. The production of lectins by recombinant means has the advantage of obtaining high amounts of proteins with defined amino-acid sequences and more precise properties. In this mini review, we provide the strategies followed to produce two different forms of frutalin in two different microbial systems: Escherichia coli and Pichia pastoris. The processing and functional properties of the recombinant frutalin obtained from these hosts are compared to those of frutalin extracted from breadfruit. Emphasis is given particularly to recombinant frutalin produced in P. pastoris, which showed a remarkable capacity as biomarker of human prostate cancer and as apoptosis-inducer of cancer cells. Recombinant frutalin production opens perspectives for its development as a new tool in human medicine. PMID:25152749

  9. Morus alba Leaf Lectin (MLL) Sensitizes MCF-7 Cells to Anoikis by Inhibiting Fibronectin Mediated Integrin-FAK Signaling through Ras and Activation of P38 MAPK

    Science.gov (United States)

    Saranya, Jayaram; Shilpa, Ganesan; Raghu, Kozhiparambil G.; Priya, Sulochana

    2017-01-01

    Lectins are a unique class of carbohydrate binding proteins/glycoproteins, and many of them possess anticancer properties. They can induce cell cycle arrest and apoptosis, inhibit protein synthesis, telomerase activity and angiogenesis in cancer cells. In the present study, we have demonstrated the effect of Morus alba leaf lectin (MLL) on anoikis induction in MCF-7 cells. Anoikis induction in cancer cells has a significant role in preventing early stage metastasis. MLL treatment in monolayers of MCF-7 cells caused significant detachment of cells in a time and concentration dependent manner. The detached cells failed to re-adhere and grew even to culture plates coated with different matrix proteins. DNA fragmentation, membrane integrity studies, annexin V staining, caspase 9 activation and upregulation of Bax/Bad confirmed that the detached cells underwent apoptosis. Upregulation of matrix metalloproteinase 9 (MMP-9) caused a decrease in fibronectin (FN) production which facilitated the cells to detach by blocking the FN mediated downstream signaling. On treatment with MLL, we have observed downregulation of integrin expression, decreased phosphorylation of focal adhesion kinase (FAK), loss in FAK-integrin interaction and active Ras. MLL treatment downregulated the levels of phosphorylated Akt and PI3K. Also, we have studied the effect of MLL on two stress activated protein kinases p38 MAPK and JNK. p38 MAPK activation was found to be elevated, but there was no change in the level of JNK. Thus our study substantiated the possible antimetastatic effect of MLL by inducing anoikis in MCF-7 cells by activation of caspase 9 and proapoptotic Bax/Bad by blockage of FN mediated integrin/FAK signaling and partly by activation of p38 MAPK. PMID:28223935

  10. Mannose-binding lectin gene polymorphisms are associated with disease activity and physical disability in untreated, anti-cyclic citrullinated peptide-positive patients with early rheumatoid arthritis

    DEFF Research Database (Denmark)

    Jacobsen, Søren; Garred, Peter; Madsen, Hans Ole

    2009-01-01

    OBJECTIVE: To study the association between polymorphisms in the mannose-binding lectin gene (MBL2) and disease activity, physical disability, and joint erosions in patients with newly diagnosed rheumatoid arthritis (RA). METHODS: Patients with early RA (n=158) not previously treated with disease...... modifying antirheumatic drugs, participating in a treatment trial (CIMESTRA study) were examined at inclusion for MBL2 pooled structural genotypes (O/O, A/O, A/A), regulatory MBL2 promoter polymorphism in position -221 (XX, XY, YY), anti-cyclic citrullinated peptide 2 antibodies (anti-CCP2), disease...... activity by Disease Activity Score-28 (DAS28 score), physical disability by Health Assessment Questionnaire (HAQ) score, and erosive changes in hands and feet (Sharp-van der Heijde score). RESULTS: Eight patients were homozygous MBL2 defective (O/O), 101 belonged to an intermediate group, and 49 were MBL2...

  11. DMPD: C-type lectin receptors in antifungal immunity. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18160296 C-type lectin receptors in antifungal immunity. Willment JA, Brown GD. Tre...nds Microbiol. 2008 Jan;16(1):27-32. Epub 2007 Dec 21. (.png) (.svg) (.html) (.csml) Show C-type lectin receptors in antifun...gal immunity. PubmedID 18160296 Title C-type lectin receptors in antifungal immunity. Author

  12. A survey of domestic species of Basidiomycetes fungi for the presence of lectins inn their carpophores

    Directory of Open Access Journals (Sweden)

    Grażyna Końska

    2014-01-01

    Full Text Available Preliminary investigations were conducted to determine the presence of active lectins in carpophores of fungi from the class Basidiomycetes, collected from natural localities in southern and south-eastern Poland. The degree of agglutination activity (expressed as the titre of agglutination of aqueous extracts was determined at room temperature (18-20°C and at +4°C in respect to human and animal erythrocytes suspended in physiological saline, part of which were additionally treated with proteolytic enzymes. From among the 104 tested species, extracts from 41 of them showed agglutination activity, among which 18 were high. In six cases, specific activity against human ABH group antigens was found. Extracts from 5 species agglutinated only animal erythrocytes, with pigeon erythrocytes being exceptionally sensitive to the lectins. Extracts from two species had distinctly higher agglutination activity at 4°C, which suggests that lectins of the "cold" agglutinin type are present in these species. Analysis of extracts from caps and stems showed that caps had a higher lectin content.

  13. Anti-insect potential of lectins from Arisaema species towards Bactrocera cucurbitae.

    Science.gov (United States)

    Kaur, Manpreet; Singh, Kuljinder; Rup, Pushpinder J; Kamboj, Sukhdev Singh; Singh, Jatinder

    2009-11-01

    Bactrocera cucurbitae (Coquillett), also known as melon fruit fly, is one of the major insect pests of cucurbits in several parts of Asia, Africa and Pacific. In the present investigation, effect of lectins from two sources i.e. Arisaema intermedium Blume and Arisaema wallichianum Hook f. (Family-Araceae) has been studied on the development of second instar larvae of melon fruit fly. The lectins were incorporated separately in artificial diet at a concentration of 10 to 160 microg ml(-1) and fed adlibitum to the second instar larvae. Both the lectins were found to prolong the development period and significantly inhibited the pupation and emergence in a dose dependent manner. Total development period was found to be prolonged by 3.5 and 2.3 days in case of larvae fed on artificial diet containing A. intermedium (AIL) and A. wallichianum (AWL), respectively. LC50 values calculated on the basis of adult emergence came out to be 32.8 and 29 microg ml(-1) for AIL and AWL, respectively. Both the lectins tested, were found to increase the activity of esterases as larvae proceeded from 24 to 72 hr of treatment. The activity of acid phosphatase decreased significantly in larvae reared on diet containing LC50 of AIL, while in case of AWL significant decrease was observed only at 72 hr of treatment. Alkaline phosphatase activity decreased significantly on treatment with both of these lectins. These results showed that AIL and AWL have promising anti-insect potential. So, lectin gene/s from either of these species can be cloned and subsequently can be employed to develop transgenics to control melon fruit flies specifically and insect pests in general. This approach could be used as a part of Integrated pest management (IPM) strategies.

  14. The lectin-like domain of thrombomodulin confers protection from neutrophil-mediated tissue damage by suppressing adhesion molecule expression via nuclear factor kappaB and mitogen-activated protein kinase pathways

    NARCIS (Netherlands)

    Conway, Edward M.; van de Wouwer, Marlies; Pollefeyt, Saskia; Jurk, Kerstin; van Aken, Hugo; de Vriese, Astrid; Weitz, Jeffrey I.; Weiler, Hartmut; Hellings, Peter W.; Schaeffer, Paul; Herbert, Jean-Marc; Collen, Désiré; Theilmeier, Gregor

    2002-01-01

    Thrombomodulin (TM) is a vascular endothelial cell (EC) receptor that is a cofactor for thrombin-mediated activation of the anticoagulant protein C. The extracellular NH(2)-terminal domain of TM has homology to C-type lectins that are involved in immune regulation. Using transgenic mice that lack

  15. Antinociceptive and Anti-inflammatory Effects of a Lectin-Like Substance from Clitoria fairchildiana R. Howard Seeds

    Directory of Open Access Journals (Sweden)

    Tatiane Santi-Gadelha

    2012-03-01

    Full Text Available Lectins are proteins that have the ability to bind specifically and reversibly to carbohydrates and glycoconjugates, without altering the structure of the glycosyl ligand. They are found in organisms such as viruses, plants and humans, and they have been shown to possess important biological activities. The objective of this study was to purify and characterize lectins in the seeds of Clitoria fairchildiana, as well as to verify their biological activities. The results indicated the presence of a lectin (CFAL in the glutelin acid protein fraction, which agglutinated native rabbit erythrocytes. CFAL was purified by column chromatography ion-exchange, DEAE-Sephacel, which was obtained from a peak of protein retained in the matrix by applying 0.5 M NaCl using the step-wise method. Electrophoretic analysis of this lectin in SDS-PAGE indicated a two band pattern protein molecular mass of approximately 100 and 116 kDa. CFAL proved to be unspecific to all carbohydrates/glycoconjugates in common use for the sugar inhibition test. This lectin showed no significant cytotoxicity to human red blood cells. It was observed that CFAL has anti-inflammatory activity in the paw edema induced by carrageenan model, in which a 64% diminution in edema was observed. Antinociceptive effects were observed for CFAL in the abdominal writhing test (induced by acetic acid, in which increasing doses of the lectin caused reduction in the number of contortions by up to 72%. It was concluded that the purified and characterized lectin from the seeds of Clitoria fairchildiana has anti-inflammatory and antinociceptive activity, and is not cytotoxic to human erythrocytes.

  16. Ovalbumin with Glycated Carboxyl Groups Shows Membrane-Damaging Activity

    Directory of Open Access Journals (Sweden)

    Ching-Chia Tang

    2017-02-01

    Full Text Available The aim of the present study was to investigate whether glycated ovalbumin (OVA showed novel activity at the lipid-water interface. Mannosylated OVA (Man-OVA was prepared by modification of the carboxyl groups with p-aminophenyl α-dextro (d-mannopyranoside. An increase in the number of modified carboxyl groups increased the membrane-damaging activity of Man-OVA on cell membrane-mimicking vesicles, whereas OVA did not induce membrane permeability in the tested phospholipid vesicles. The glycation of carboxyl groups caused a notable change in the gross conformation of OVA. Moreover, owing to their spatial positions, the Trp residues in Man-OVA were more exposed, unlike those in OVA. Fluorescence quenching studies suggested that the Trp residues in Man-OVA were located on the interface binds with the lipid vesicles, and their microenvironment was abundant in positively charged residues. Although OVA and Man-OVA showed a similar binding affinity for lipid vesicles, the lipid-interacting feature of Man-OVA was distinct from that of OVA. Chemical modification studies revealed that Lys and Arg residues, but not Trp residues, played a crucial role in the membrane-damaging activity of Man-OVA. Taken together, our data suggest that glycation of carboxyl groups causes changes in the structural properties and membrane-interacting features of OVA, generating OVA with membrane-perturbing activities at the lipid-water interface.

  17. Microglial Lectins in Health and Neurological Diseases

    Directory of Open Access Journals (Sweden)

    Jian Jing Siew

    2018-05-01

    Full Text Available Microglia are the innate sentinels of the central nervous system (CNS and are responsible for the homeostasis and immune defense of the CNS. Under the influence of the local environment and cell-cell interaction, microglia exhibit a multidimensional and context-dependent phenotypes that can be cytotoxic and neuroprotective. Recent studies suggest that microglia express multitudinous types of lectins, including galectins, Siglecs, mannose-binding lectins (MBLs and other glycan binding proteins. Because most studies that examine lectins focus on the peripheral system, the functions of lectins have not been critically investigated in the CNS. In addition, the types of brain cells that contribute to the altered levels of lectins present in diseases are often unclear. In this review, we will discuss how galectins, Siglecs, selectins and MBLs contribute to the dynamic functions of microglia. The interacting ligands of these lectins are complex glycoconjugates, which consist of glycoproteins and glycolipids that are expressed on microglia or surrounding cells. The current understanding of the heterogeneity and functions of glycans in the brain is limited. Galectins are a group of pleotropic proteins that recognize both β-galactoside-containing glycans and non- β-galactoside-containing proteins. The function and regulation of galectins have been implicated in immunomodulation, neuroinflammation, apoptosis, phagocytosis and oxidative bursts. Most Siglecs are expressed at a low level on the plasma membrane and bind to sialic acid residues for immunosurveillance and cell-cell communication. Siglecs are classified based on their inhibitory and activatory downstream signaling properties. Inhibitory Siglecs negatively regulate microglia activation upon recognizing the intact sialic acid patterns and vice versa. MBLs are expressed upon infection in cytoplasm and can be secreted in order to recognize molecules containing terminal mannose as an innate immune

  18. Lectin affinity electrophoresis.

    Science.gov (United States)

    Kobayashi, Yuka

    2014-01-01

    An interaction or a binding event typically changes the electrophoretic properties of a molecule. Affinity electrophoresis methods detect changes in the electrophoretic pattern of molecules (mainly macromolecules) that occur as a result of biospecific interactions or complex formation. Lectin affinity electrophoresis is a very effective method for the detection and analysis of trace amounts of glycobiological substances. It is particularly useful for isolating and separating the glycoisomers of target molecules. Here, we describe a sensitive technique for the detection of glycoproteins separated by agarose gel-lectin affinity electrophoresis that uses antibody-affinity blotting. The technique is tested using α-fetoprotein with lectin (Lens culinaris agglutinin and Phaseolus vulgaris agglutinin)-agarose gels.

  19. Active explorers show low learning performance in a social insect

    Institute of Scientific and Technical Information of China (English)

    Eve UDINO; Margot PEREZ; Claudio CARERE; Patrizia d'ETTORRE

    2017-01-01

    An intriguing question in behavioral biology is whether consistent individual differences (called animal personalities) relate to variation in cognitive performance because commonly measured personality traits may be associated with risk-reward trade-offs.Social insects,whose learning abilities have been extensively characterized,show consistent behavioral variability,both at colony and at individual level.We investigated the possible link between personality traits and learning performance in the carpenter ant Camponotus aethiops.Exploratory activity,sociability,and aggression were assessed twice in ant foragers.Behaviors differed among individuals,they were partly repeatable across time and exploratory activity correlated positively with aggression.Learning abilities were quantified by differential conditioning of the maxilla-labium extension response,a task that requires cue perception and information storage.We found that exploratory activity of individual ants significantly predicted learning performance:"active-explorers" were slower in learning the task than "inactive-explorers".The results suggest for the first time a link between a personality trait and cognitive performance in eusocial insects,and that the underlying individual variability could affect colony performance and success.

  20. P17, an Original Host Defense Peptide from Ant Venom, Promotes Antifungal Activities of Macrophages through the Induction of C-Type Lectin Receptors Dependent on LTB4-Mediated PPARγ Activation

    Directory of Open Access Journals (Sweden)

    Khaddouj Benmoussa

    2017-11-01

    Full Text Available Despite the growing knowledge with regard to the immunomodulatory properties of host defense peptides, their impact on macrophage differentiation and on its associated microbicidal functions is still poorly understood. Here, we demonstrated that the P17, a new cationic antimicrobial peptide from ant venom, induces an alternative phenotype of human monocyte-derived macrophages (h-MDMs. This phenotype is characterized by a C-type lectin receptors (CLRs signature composed of mannose receptor (MR and Dectin-1 expression. Concomitantly, this activation is associated to an inflammatory profile characterized by reactive oxygen species (ROS, interleukin (IL-1β, and TNF-α release. P17-activated h-MDMs exhibit an improved capacity to recognize and to engulf Candida albicans through the overexpression both of MR and Dectin-1. This upregulation requires arachidonic acid (AA mobilization and the activation of peroxisome proliferator-activated receptor gamma (PPARγ nuclear receptor through the leukotriene B4 (LTB4 production. AA/LTB4/PPARγ/Dectin-1-MR signaling pathway is crucial for P17-mediated anti-fungal activity of h-MDMs, as indicated by the fact that the activation of this axis by P17 triggered ROS production and inflammasome-dependent IL-1β release. Moreover, we showed that the increased anti-fungal immune response of h-MDMs by P17 was dependent on intracellular calcium mobilization triggered by the interaction of P17 with pertussis toxin-sensitive G-protein-coupled receptors on h-MDMs. Finally, we also demonstrated that P17-treated mice infected with C. albicans develop less severe gastrointestinal infection related to a higher efficiency of their macrophages to engulf Candida, to produce ROS and IL-1β and to kill the yeasts. Altogether, these results identify P17 as an original activator of the fungicidal response of macrophages that acts upstream PPARγ/CLRs axis and offer new immunomodulatory therapeutic perspectives in the field of

  1. Glycoprofiling of Early Gastric Cancer Using Lectin Microarray Technology.

    Science.gov (United States)

    Li, Taijie; Mo, Cuiju; Qin, Xue; Li, Shan; Liu, Yinkun; Liu, Zhiming

    2018-01-01

    Recently, studies have reported that protein glycosylation plays an important role in the occurrence and development of cancer. Gastric cancer is a common cancer with high morbidity and mortality owing to most gastric cancers are discovered only at an advanced stage. Here, we aim to discover novel specific serum glycanbased biomarkers for gastric cancer. A lectin microarray with 50 kinds of tumor-associated lectin was used to detect the glycan profiles of serum samples between early gastric cancer and healthy controls. Then lectin blot was performed to validate the differences. The result of the lectin microarray showed that the signal intensities of 13 lectins showed significant differences between the healthy controls and early gastric cancer. Compared to the healthy, the normalized fluorescent intensities of the lectins PWA, LEL, and STL were significantly increased, and it implied that their specifically recognized GlcNAc showed an especially elevated expression in early gastric cancer. Moreover, the binding affinity of the lectins EEL, RCA-II, RCA-I, VAL, DSA, PHA-L, UEA, and CAL were higher in the early gastric cancer than in healthy controls. These glycan structures containing GalNAc, terminal Galβ 1-4 GlcNAc, Tri/tetraantennary N-glycan, β-1, 6GlcNAc branching structure, α-linked fucose residues, and Tn antigen were elevated in gastric cancer. While the two lectins CFL GNL reduced their binding ability. In addition, their specifically recognized N-acetyl-D-galactosamine structure and (α-1,3) mannose residues were decreased in early gastric cancer. Furthermore, lectin blot results of LEL, STL, PHA-L, RCA-I were consistent with the results of the lectin microarray. The findings of our study clarify the specific alterations for glycosylation during the pathogenesis of gastric cancer. The specific high expression of GlcNAc structure may act as a potential early diagnostic marker for gastric cancer.

  2. High-Resolution Observations of a Filament showing Activated Barb

    Science.gov (United States)

    Joshi, Anand; Martin, Sara F.; Mathew, Shibu; Srivastava, Nandita

    2012-07-01

    Analysis of a filament showing an activated barb using observations from the Dutch Open Telescope (DOT) on 2010 August 20 are presented. The DOT takes Doppler images in Hα, among other wavelengths, in a region about 110 × 110 arcsec^{2} in area, at a cadence of 30~seconds. The offline image restoration technique of speckle reconstruction is applied to obtain diffraction limited images. The filament developed a new barb in 10~minutes, which disappeared within the next 35~minutes. Such a rapid formation and disappearance of a filament barb is unusual, and has not been reported earlier. Line-of-sight velocity maps were constructed from the Doppler images of the target filament. We observe flows in the filament spine towards the barb location prior to its formation, and flows in the barb towards the spine during its disappearance. Photospheric magnetograms from Heliospheric Magnetic Imager on board the Solar Dynamics Observatory, at a cadence of 45~seconds, were used to determine the changes in magnetic flux in the region surrounding the barb location. The variation of magnetic flux in this duration supports the view that barbs are rooted in minor magnetic polarity. Our analysis shows that barbs can be short-lived and formation and disappearance of the barb was associated with cancellation of magnetic flux.

  3. High-Mannose Specific Lectin and Its Recombinants from a Carrageenophyta Kappaphycus alvarezii Represent a Potent Anti-HIV Activity Through High-Affinity Binding to the Viral Envelope Glycoprotein gp120.

    Science.gov (United States)

    Hirayama, Makoto; Shibata, Hiromi; Imamura, Koji; Sakaguchi, Takemasa; Hori, Kanji

    2016-02-01

    We previously reported that a high-mannose binding lectin KAA-2 from the red alga Kappaphycus alvarezii, which is an economically important species and widely cultivated as a source of carrageenans, had a potent anti-influenza virus activity. In this study, the full-length sequences of two KAA isoforms, KAA-1 and KAA-2, were elucidated by a combination of peptide mapping and complementary DNA (cDNA) cloning. They consisted of four internal tandem-repeated domains, which are conserved in high-mannose specific lectins from lower organisms, including a cyanobacterium Oscillatoria agardhii and a red alga Eucheuma serra. Using an Escherichia coli expression system, an active recombinant form of KAA-1 (His-tagged rKAA-1) was successfully generated in the yield of 115 mg per liter of culture. In a detailed oligosaccharide binding analysis by a centrifugal ultrafiltration-HPLC method with 27 pyridylaminated oligosaccharides, His-tagged rKAA-1 and rKAA-1 specifically bound to high-mannose N-glycans with an exposed α1-3 mannose in the D2 arm as the native lectin did. Predicted from oligosaccharide binding specificity, a surface plasmon resonance analysis revealed that the recombinants exhibit strong interaction with gp120, a heavily glycosylated envelope glycoprotein of HIV with high association constants (1.48 - 1.61 × 10(9) M(-1)). Native KAAs and the recombinants inhibited the HIV-1 entry at IC50s of low nanomolar levels (7.3-12.9 nM). Thus, the recombinant proteins would be useful as antiviral reagents targeting the viral surface glycoproteins with high-mannose N-glycans, and the cultivated alga K. alvarezii could also be a good source of not only carrageenans but also this functional lectin(s).

  4. Association of C-Type Lectin Mincle with FcεRIβγ Subunits Leads to Functional Activation of RBL-2H3 Cells through Syk.

    Science.gov (United States)

    Honjoh, Chisato; Chihara, Kazuyasu; Yoshiki, Hatsumi; Yamauchi, Shota; Takeuchi, Kenji; Kato, Yuji; Hida, Yukio; Ishizuka, Tamotsu; Sada, Kiyonao

    2017-04-10

    Macrophage-inducible C-type lectin (Mincle) interacts with the γ-subunit of high-affinity IgE receptor (FcεRIγ) and activates Syk by recognizing its specific ligand, trehalose-6,6'-dimycolate, a glycolipid produced by Mycobacterium tuberculosis. It has been suggested that mast cells participate in the immune defense against pathogenic microbes including M. tuberculosis, although the functions are still uncertain. In this study, we examined the Mincle-mediated signaling pathway and cellular responses using RBL-2H3 cells. Mincle formed a protein complex with not only FcεRIγ but also FcεRIβ in a stable cell line expressing myc-tagged Mincle. In addition, engagement of Mincle increased the levels of protein tyrosine phosphorylation and ERK phosphorylation. A pull-down assay demonstrated that cross-linking of Mincle induced binding of FcεRIβγ subunits to the Src homology 2 domain of Syk. Pharmacological and genetic studies indicated that activation of Syk was critical for Mincle-mediated activation of phospholipase Cγ2, leading to the activation of ERK and nuclear factor of activated T cells. Moreover, engagement of Mincle efficiently induced up-regulation of characteristic mast cell genes in addition to degranulation. Taken together, our present results suggest that mast cells contribute to Mincle-mediated immunity through Syk activation triggered by association with the FcεRIβγ complex.

  5. Purification, characterization and biological effect of lectin from the marine sponge Stylissa flexibilis (Lévi, 1961).

    Science.gov (United States)

    Hung, Le Dinh; Ly, Bui Minh; Hao, Vo Thi; Trung, Dinh Thanh; Trang, Vo Thi Dieu; Trinh, Phan Thi Hoai; Ngoc, Ngo Thi Duy; Quang, Thai Minh

    2018-02-01

    SFL, a lectin from the marine sponge Stylissa flexibilis was purified by cold ethanol precipitation followed by ion exchange chromatography on DEAE Sepharose column and Sephacryl S-200 gel filtration. SFL is a dimeric glycoprotein of 32kDa subunits linked by a disulfide bridge with a molecular mass of 64kDa by SDS-PAGE and 65kDa by Sephacryl S-200 gel filtration. SFL preferentially agglutinated enzyme treated human A erythrocytes. The activity of lectin was strongly inhibited by monosaccharide d-galactose and glycoproteins asialo-porcine stomach mucin and asialo-fetuin. The lectin was Ca 2+ dependent, stable over a range of pH from 5 to 8, and up to 60°C for 30min. The N-terminal amino acid sequence of SFL was also determined and a blast search on amino acid sequences revealed that the protein showed similarity only with lectins from the marine sponge Spheciospongia vesparia. SFL caused agglutination of Vibrio alginolyticus and V. parahaemolyticus in a dose dependent manner and inhibited the growth rates of the virulent bacterial strains. Growth inhibition of V. alginolyticus and V. parahaemolyticus with SFL was not observed in the presence of d-galactose or asialo-porcine stomach mucin, suggesting that the lectin caused the agglutination through binding to the target receptor(s) on the surface of Vibrios. Thus, the marine sponge S. flexibilis could promise to be a good source of a lectin(s) that may be useful as a carbohydrate probe and an antibacterial reagent. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. The Oral Antimalarial Drug Tafenoquine Shows Activity against Trypanosoma brucei.

    Science.gov (United States)

    Carvalho, Luis; Martínez-García, Marta; Pérez-Victoria, Ignacio; Manzano, José Ignacio; Yardley, Vanessa; Gamarro, Francisco; Pérez-Victoria, José M

    2015-10-01

    The protozoan parasite Trypanosoma brucei causes human African trypanosomiasis, or sleeping sickness, a neglected tropical disease that requires new, safer, and more effective treatments. Repurposing oral drugs could reduce both the time and cost involved in sleeping sickness drug discovery. Tafenoquine (TFQ) is an oral antimalarial drug belonging to the 8-aminoquinoline family which is currently in clinical phase III. We show here that TFQ efficiently kills different T. brucei spp. in the submicromolar concentration range. Our results suggest that TFQ accumulates into acidic compartments and induces a necrotic process involving cell membrane disintegration and loss of cytoplasmic content, leading to parasite death. Cell lysis is preceded by a wide and multitarget drug action, affecting the lysosome, mitochondria, and acidocalcisomes and inducing a depolarization of the mitochondrial membrane potential, elevation of intracellular Ca(2+), and production of reactive oxygen species. This is the first report of an 8-aminoquinoline demonstrating significant in vitro activity against T. brucei. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  7. Purification and characterization of a new type lactose-binding Ulex europaeus lectin by affinity chromatography.

    Science.gov (United States)

    Konami, Y; Yamamoto, K; Osawa, T

    1991-02-01

    A new type lactose-binding lectin was purified from extracts of Ulex europaeus seeds by affinity chromatography on a column of galactose-Sepharose 4B, followed by gel filtration on Sephacryl S-300. This lectin, designated as Ulex europaeus lectin III (UEA-III), was found to be inhibited by lactose. The dimeric lectin is a glycoprotein with a molecular mass of 70,000 Da; it consists of two apparently identical subunits of a molecular mass of 34,000 Da. Compositional analysis showed that this lectin contains 30% carbohydrate and a large amount of aspartic acid, serine and valine, but no sulfur-containing amino acids. The N-terminal amino-acid sequences of L-fucose-binding Ulex europaeus lectin I (UEA-I) and di-N-acetylchitobiose-binding Ulex europaeus lectin II (UEA-II), both of which we have already purified and characterized, and that of UEA-III were determined and compared.

  8. Synthetic analogs of anoplin show improved antimicrobial activities

    DEFF Research Database (Denmark)

    Munk, Jens; Uggerhøj, Lars Erik; Poulsen, Tanja Juul

    2013-01-01

    We present the antimicrobial and hemolytic activities of the decapeptide anoplin and 19 analogs thereof tested against methicillin-resistant Staphylococcus aureus ATCC 33591 (MRSA), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), vancomycin-resistant Enterococcus faecium (ATCC...... that increasing the charge and/or hydrophobicity improves antimicrobial activity and increases hemolytic activity. For each strain tested, we identify at least six anoplin analogs with an improved therapeutic index compared with anoplin, the only exception being Enterococcus faecium, against which only few...

  9. Animal lectins: potential receptors for ginseng polysaccharides

    Directory of Open Access Journals (Sweden)

    So Hee Loh

    2017-01-01

    Full Text Available Panax ginseng Meyer, belonging to the genus Panax of the family Araliaceae, is known for its human immune system-related effects, such as immune-boosting effects. Ginseng polysaccharides (GPs are the responsible ingredient of ginseng in immunomodulation, and are classified as acidic and neutral GPs. Although GPs participate in various immune reactions including the stimulation of immune cells and production of cytokines, the precise function of GPs together with its potential receptor(s and their signal transduction pathways have remained largely unknown. Animal lectins are carbohydrate-binding proteins that are highly specific for sugar moieties. Among many different biological functions in vivo, animal lectins especially play important roles in the immune system by recognizing carbohydrates that are found exclusively on pathogens or that are inaccessible on host cells. This review summarizes the immunological activities of GPs and the diverse roles of animal lectins in the immune system, suggesting the possibility of animal lectins as the potential receptor candidates of GPs and giving insights into the development of GPs as therapeutic biomaterials for many immunological diseases.

  10. Lectins as endocytic ligands: an assessment of lectin binding and uptake to rabbit conjunctival epithelial cells.

    Science.gov (United States)

    Qaddoumi, Mohamed; Lee, Vincent H L

    2004-07-01

    To investigate the binding and uptake pattern of three plant lectins in rabbit conjunctival epithelial cells (RCECs) with respect to their potential for enhancing cellular macromolecular uptake. Three fluorescein-labeled plant lectins (Lycoperison esculentum, TL; Solanum tuberosum, STL; and Ulex europaeus 1, UEA-1) were screened with respect to time-, concentration-, and temperature-dependent binding and uptake. Chitin (30 mg/ml) and L-alpha-fucose (10 mM) were used as inhibitory sugars to correct for nonspecific binding of TL or STL and UEA-1, respectively. Confocal microscopy was used to confirm internalization of STL. The binding and uptake of all three lectins in RCECs was time-dependent (reaching a plateau at 1-2 h period) and saturable at 1-h period. The rank order of affinity constants (km) was STL>TL>UEA-1 with values of 0.39>0.48>4.81 microM, respectively. However, maximal, specific binding/uptake potential was in the order UEA-1>STL>TL with values of 53.7, 52.3, and 15.0 nM/mg of cell protein, respectively. Lectins showed temperature dependence in their uptake, with STL exhibiting the highest endocytic capacity. Internalized STL was visualized by confocal microscopy to be localized to the cell membrane and cytoplasm. Based on favorable binding and uptake characteristics, potato lectin appears to be a useful candidate for further investigation as an ocular drug delivery system.

  11. Characterization of the okra mucilage by interaction with Gal, GalNAc and GlcNAc specific lectins.

    Science.gov (United States)

    Wu, A M; Jiang, Y J; Hwang, P Y; Shen, F S

    1995-02-23

    A bio-active polysaccharide, which was the major component of the extract of the common okra, Hibiscus esculentus, was isolated from the extract by precipitation with ethanol between 28.5 to 45%. According to a previous report (Whistler, R.L. and Conrad, H.E. (1954) J. Am. Chem. Soc. 76, 1673-1674), this polysaccharide contains the Gal alpha 1-->4Gal sequence, which is the ligand for the uropathogenic Escherichia coli and toxic lectins. Analysis of the binding property of the okra polysaccharide by precipitin assay with Gal, GalNAc and GlcNAc specific lectins showed that this okra mucilage reacted best with Mistletoe toxic lectin-I (ML-I) and precipitated over 80% of the ML-I nitrogen (5.1 micrograms N) added. It also precipitated well with Abrus precatorius (APA), Momordica charantia (MCA) and Ricinus communis (RCA1) agglutinins, but poorly with other lectins. The results obtained suggest that this polysaccharide is a valuable reagent to differentiate Gal specific lectins from the GalNAc and/or GlcNAc specific series.

  12. Psychopaths show enhanced amygdala activation during fear conditioning

    Directory of Open Access Journals (Sweden)

    Douglas eSchultz

    2016-03-01

    Full Text Available Psychopathy is a personality disorder characterized by emotional deficits and a failure to inhibit impulsive behavior and is often subdivided into primary and secondary psychopathic subtypes. The maladaptive behavior related to primary psychopathy is thought to reflect constitutional fearlessness, while the problematic behavior related to secondary psychopathy is motivated by other factors. The fearlessness observed in psychopathy has often been interpreted as reflecting a fundamental deficit in amygdala function, and previous studies have provided support for a low-fear model of psychopathy. However, many of these studies fail to use appropriate screening procedures, use liberal inclusion criteria, or have used unconventional approaches to assay amygdala function. We measured brain activity with BOLD imaging in primary and secondary psychopaths and non-psychopathic control subjects during Pavlovian fear conditioning. In contrast to the low-fear model, we observed normal fear expression in primary psychopaths. Psychopaths also displayed greater differential BOLD activity in the amygdala relative to matched controls. Inverse patterns of activity were observed in the anterior cingulate cortex (ACC for primary versus secondary psychopaths. Primary psychopaths exhibited a pattern of activity in the dorsal and ventral ACC consistent with enhanced fear expression, while secondary psychopaths exhibited a pattern of activity in these regions consistent with fear inhibition. These results contradict the low-fear model of psychopathy and suggest that the low fear observed for psychopaths in previous studies may be specific to secondary psychopaths.

  13. Glycan microarray analysis of the carbohydrate-recognition specificity of native and recombinant forms of the lectin ArtinM.

    Science.gov (United States)

    Liu, Y; Cecílio, N T; Carvalho, F C; Roque-Barreira, M C; Feizi, T

    2015-12-01

    This article contains data related to the researc.h article entitled "Yeast-derived ArtinM shares structure, carbohydrate recognition, and biological effects with native ArtinM" by Cecílio et al. (2015) [1]. ArtinM, a D-mannose-binding lectin isolated from the seeds of Artocarpus heterophyllus, exerts immunomodulatory and regenerative activities through its Carbohydrate Recognition Domain (CRD) (Souza et al., 2013; Mariano et al., 2014 [2], [3]). The limited availability of the native lectin (n-ArtinM) led us to characterize a recombinant form of the protein, obtained by expression in Saccharomyces cerevisiae (y-ArtinM). We compared the carbohydrate-binding specificities of y-ArtinM and n-ArtinM by analyzing the binding of biotinylated preparations of the two lectin forms using a neoglycolipid (NGL)-based glycan microarray. Data showed that y-ArtinM mirrored the specificity exhibited by n-ArtinM.

  14. Evaluation of glycophenotype in breast cancer by quantum dot-lectin histochemistry

    Science.gov (United States)

    Andrade, Camila G; Cabral Filho, Paulo E; Tenório, Denise PL; Santos, Beate S; Beltrão, Eduardo IC; Fontes, Adriana; Carvalho, Luiz B

    2013-01-01

    Cell surface glycoconjugates play an important role in differentiation/dedifferentiation processes and lectins are employed to evaluate them by several methodologies. Fluorescent probes are considered a valuable tool because of their ability to provide a particular view, and are more detailed and sensitive in terms of cell structure and molecular content. The aim of this study was to evaluate and compare the expression and distribution of glycoconjugates in normal human breast tissue, and benign (fibroadenoma), and malignantly transformed (invasive ductal carcinoma) breast tissues. For this, we used mercaptosuccinic acid-coated Cadmium Telluride (CdTe) quantum dots (QDs) conjugated with concanavalin A (Con A) or Ulex europaeus agglutinin I (UEA I) lectins to detect α-D-glucose/mannose and L-fucose residues, respectively. The QD-lectin conjugates were evaluated by hemagglutination activity tests and carbohydrate inhibition assays, and were found to remain functional, keeping their fluorescent properties and carbohydrate recognition ability. Fluorescence images showed that different regions of breast tissue expressed particular types of carbohydrates. While the stroma was preferentially and intensely stained by QD-Con A, ductal cells were preferentially labeled by QD-UEA I. These results indicate that QD-lectin conjugates can be used as molecular probes and can help to elucidate the glycoconjugate profile in biological processes. PMID:24324334

  15. Insurance Applications of Active Fault Maps Showing Epistemic Uncertainty

    Science.gov (United States)

    Woo, G.

    2005-12-01

    Insurance loss modeling for earthquakes utilizes available maps of active faulting produced by geoscientists. All such maps are subject to uncertainty, arising from lack of knowledge of fault geometry and rupture history. Field work to undertake geological fault investigations drains human and monetary resources, and this inevitably limits the resolution of fault parameters. Some areas are more accessible than others; some may be of greater social or economic importance than others; some areas may be investigated more rapidly or diligently than others; or funding restrictions may have curtailed the extent of the fault mapping program. In contrast with the aleatory uncertainty associated with the inherent variability in the dynamics of earthquake fault rupture, uncertainty associated with lack of knowledge of fault geometry and rupture history is epistemic. The extent of this epistemic uncertainty may vary substantially from one regional or national fault map to another. However aware the local cartographer may be, this uncertainty is generally not conveyed in detail to the international map user. For example, an area may be left blank for a variety of reasons, ranging from lack of sufficient investigation of a fault to lack of convincing evidence of activity. Epistemic uncertainty in fault parameters is of concern in any probabilistic assessment of seismic hazard, not least in insurance earthquake risk applications. A logic-tree framework is appropriate for incorporating epistemic uncertainty. Some insurance contracts cover specific high-value properties or transport infrastructure, and therefore are extremely sensitive to the geometry of active faulting. Alternative Risk Transfer (ART) to the capital markets may also be considered. In order for such insurance or ART contracts to be properly priced, uncertainty should be taken into account. Accordingly, an estimate is needed for the likelihood of surface rupture capable of causing severe damage. Especially where a

  16. Three-dimensional structure of lectin from Dioclea violacea and comparative vasorelaxant effects with Dioclea rostrata

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, B.A.M.; Bezerra, M.J.B.; Bezerra, G.A.; Alencar, K.L.L.; Nascimento, K.S.; Naganao, C.S.; Sampaio, A.H.; Cavada, B.S. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil); Delatorre, P. [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil); Rodrigues, N.V.; Pires, A.F.; Assreuy, A.M.S. [Universidade Estadual do Ceara (UECE), Fortaleza, CE (Brazil); Marins, J.L. [Universidade Federal de Pelotas (UFPel), Pelotas, RS (Brazil)

    2012-07-01

    Full text: Lectins are a structural heterogeneous group of proteins possessing at least one non-catalytic domain that binds reversibly to a specific mono or oligosaccharide. Diocleinae lectins exhibit glucose/mannose monosaccharide binding specificity and studies of their chemical and physicochemical properties revealed a high degree of identity in their amino acid sequences and three dimensional structures. This study investigated structural/functional relationships between lectins obtained from Dioclea violacea (DVL) and Dioclea rostrata (DRL). The purified lectin (DVL) was solubilized in 20 mM Tris-HCl pH 7.6 with 5 mM CaCl{sub 2} and MnCl{sub 2} buffer and incubated during one hour before the crystallization experiments with the ligand X-Man (5-bromo-4-chloro-3-indolyl-{alpha}-D-mannose) at 3 mM. Crystals of DVL grew in condition 33 of Crystal Screen I (4M Sodium formate) and belong to the orthorhombic space group I222. The structure of DVL at 2.6 resolution was obtained by molecular replacement using the coordinates of DRL (PDB code 2ZBJ), after the last refinement the structure presented R factor of 0.23 and R free of 0.27. The crystal structures reveal differences between them and could be related to relaxant activity. The conformation of residues HIS51, HIS131 and GLU205 and others positioned at CRD lead to different lectin binding activities. In fact, the pocket in DVL is small and deep and promotes weak interaction with carbohydrates, while DRL pocket is large and shallow, allowing strong interaction between CRD and sugars. This can explain why DVL and DRL elicited different degrees of aorta relaxation showing maximal effects of 43 % and 96 %, respectively. (author)

  17. Identification of structural and secretory lectin-binding glycoproteins of normal and cancerous human prostate.

    Science.gov (United States)

    Lad, P M; Cooper, J F; Learn, D B; Olson, C V

    1984-12-07

    We have utilized the technique of lectin-loading of SDS gels with iodinated concanavalin A and wheat germ agglutinin to identify glycoproteins in prostatic and seminal fluids as well as in prostate tissue fractions. The following subunits which bound both lectins were detected: (a) 50, 43 and 38 kDa subunits common to prostatic and seminal fluids, and an additional 55 kDa subunit which predominates only in prostatic fluid; (b) 78, 55, 50 and 43 kDa subunits in prostatic tissue cytosol and (c) 195, 170, 135, 116 and 95 kDa subunits present in the particulate fractions of prostatic tissue. Immunoblotting using specific rabbit antibodies revealed the 50 kDa band to be prostatic acid phosphatase and the 38 kDa band to be prostate-specific antigen. Interestingly, antibodies directed toward prostatic acid phosphatase were found to cross-react with the 43 kDa band. Fractionation on sucrose gradients showed that several of these particulate glycoproteins were associated with a vesicle fraction enriched in adenylate cyclase activity, implying that they are plasma membrane glycoproteins. Comparison of soluble and particulate fractions of normal and cancerous tissue homogenates was made by densitometric scanning of autoradiograms of lectin-loaded gels. Similar relative intensities of lectin-binding were obtained for corresponding proteins in normal and cancerous tissue fractions. Also, immunoblotting showed no differences in prostatic acid phosphatase or prostate-specific antigen between normal and cancerous soluble homogenate fractions. Our results suggest that major lectin-binding proteins are conserved in the transition from normal to cancerous tissue. These results may be useful in developing a multiple-marker profile of metastatic prostate cancer and for the design of imaging agents, such as monoclonal antibodies, to prominent soluble and particulate prostate glycoproteins.

  18. Immunomodulatory response of mice splenocytes induced by RcaL, a lectin isolated from cobia fish (Rachycentron canadum) serum.

    Science.gov (United States)

    Coriolano, Marília Cavalcanti; Silva, Cynarha Daysy Cardoso da; Melo, Cristiane Moutinho Lagos de; Bezerra, Ranilson de Souza; Santos, Athiê Jorge Guerra; Pereira, Valéria Rêgo Alves; Coelho, Luana Cassandra Breitenbach Barroso

    2012-11-01

    This work reports the isolation of a serum lectin from cobia fish (Rachycentron canadum) named RcaL. Immunomodulatory activity on mice splenocyte experimental cultures through cytotoxic assays and cytokine production were also performed. RcaL was obtained through precipitation with ammonium sulphate and affinity chromatography on a Concanavalin A-Sepharose 4B column. The ammonium sulphate fraction F3 showed the highest specific hemagglutinating activity and was applied to affinity chromatography. The lectin was eluted with methyl-α-D-mannopyranoside. RcaL showed highest affinity for methyl-α-D-mannopyranoside and D-mannose; eluted fractions of RcaL agglutinated rabbit erythrocytes (titre, 128(-1)) retained 66 % of chromatographed lectin activity, and the obtained purification factor was 1.14. Under reducing conditions, a polypeptide band of 19.2 kDa was revealed in sodium dodecyl sulphate polyacrylamide gel electrophoresis (PAGE). PAGE confirmed RcaL as an acidic protein revealed in a single band. Cytotoxic and immunomodulatory assays with RcaL in mice splenocyte cultures showed that the lectin was not cytotoxic and induced higher interferon gamma and nitric oxide production in splenocyte cultures. Purified RcaL induced preferential Th1 response, suggesting that it acts as an immunomodulatory compound.

  19. Complement-mediated neutralization of dengue virus requires mannose-binding lectin

    DEFF Research Database (Denmark)

    Avirutnan, Panisadee; Hauhart, Richard E; Marovich, Mary A

    2011-01-01

    -dependent activation of the complement cascade neutralized insect cell-derived West Nile virus (WNV) in cell culture and restricted pathogenesis in mice. Here, we investigated the antiviral activity of MBL in infection by dengue virus (DENV), a related flavivirus. Using a panel of naïve sera from mouse strains...... with lower levels. Our studies suggest that allelic variation of MBL in humans may impact complement-dependent control of DENV pathogenesis. IMPORTANCE Dengue virus (DENV) is a mosquito-transmitted virus that causes a spectrum of clinical disease in humans ranging from subclinical infection to dengue...... hemorrhagic fever and dengue shock syndrome. Four serotypes of DENV exist, and severe illness is usually associated with secondary infection by a different serotype. Here, we show that mannose-binding lectin (MBL), a pattern recognition molecule that initiates the lectin pathway of complement activation...

  20. Heterocomplexes of mannose-binding lectin and the pentraxins PTX3 or SAP trigger cross-activation of the complement system

    DEFF Research Database (Denmark)

    Ma, Ying Jie; Doni, Andrea; Skjødt, Mikkel-Ole

    2011-01-01

    The long pentraxin 3 (PTX3), serum amyloid P component (SAP) and C-reactive protein (CRP) belong to the pentraxin family of pattern recognition molecules involved in tissue homeostasis and innate immunity. They interact with C1q from the classical complement pathway. Whether this also occurs via...... the analogous mannose-binding lectin (MBL) from the lectin complement pathway is unknown. Thus, we investigated the possible interaction between MBL and the pentraxins. We report that MBL bound PTX3 and SAP partly via its collagen-like domain, but not CRP. MBL:PTX3 complex formation resulted in recruitment of C......1q, but this was not seen for the MBL:SAP complex. However, both MBL:PTX3 and MBL:SAP complexes enhanced C4 and C3 deposition and opsonophagocytosis of Candida albicans by polymorphonuclear leukocytes. Interaction between MBL and PTX3 lead to communication between the lectin and classical complement...

  1. The third dimension of reading the sugar code by lectins: design of glycoclusters with cyclic scaffolds as tools with the aim to define correlations between spatial presentation and activity.

    Science.gov (United States)

    Murphy, Paul V; André, Sabine; Gabius, Hans-Joachim

    2013-04-04

    Coding of biological information is not confined to nucleic acids and proteins. Endowed with the highest level of structural versatility among biomolecules, the glycan chains of cellular glycoconjugates are well-suited to generate molecular messages/signals in a minimum of space. The sequence and shape of oligosaccharides as well as spatial aspects of multivalent presentation are assumed to underlie the natural specificity/selectivity that cellular glycans have for endogenous lectins. In order to eventually unravel structure-activity profiles cyclic scaffolds have been used as platforms to produce glycoclusters and afford valuable tools. Using adhesion/growth-regulatory galectins and the pan-galectin ligand lactose as a model, emerging insights into the potential of cyclodextrins, cyclic peptides, calixarenes and glycophanes for this purpose are presented herein. The systematic testing of lectin panels with spatially defined ligand presentations can be considered as a biomimetic means to help clarify the mechanisms, which lead to the exquisite accuracy at which endogenous lectins select their physiological counterreceptors from the complexity of the cellular glycome.

  2. IgG4 anti-phospholipase A2 receptor might activate lectin and alternative complement pathway meanwhile in idiopathic membranous nephropathy: an inspiration from a cross-sectional study.

    Science.gov (United States)

    Yang, Yang; Wang, Chao; Jin, Liping; He, Fagui; Li, Changchun; Gao, Qingman; Chen, Guanglei; He, Zhijun; Song, Minghui; Zhou, Zhuliang; Shan, Fujun; Qi, Ka; Ma, Lu

    2016-08-01

    The deposition of IgG4 of antibodies against phospholipase A2 receptor (anti-PLA2R) is predominating in the kidneys of patients with idiopathic membranous nephropathy, while its predictive value has not been determined. It was a retrospective study, and 438 patients were included. Serum samples of two time points [before intervention (baseline) and after 1.5-year treatment (endpoint)] were detected for total and IgG4 anti-PLA2R. IgG4 IgG4 subclass and the achievement of CR; (3) bi-negativity of IgG4 has a high accuracy of predicting CR compared with total antibodies; (4) in patients of bi-positivity, those achieving CR showed lower MASP-1/2, MBL, C3a, C5a, FB, Ba and Bb than patients failing to achieve CR; (5) the titers of endpoint and decrease in Ba and Bb were associated with improvement of 24 h-UP in those of bi-positivity; and (6) the decrease in Ba was a significant factor for achieving CR in those of bi-positivity. Continuous IgG4 negativity was a useful tool to predict the achievement of CR; however, in patients of continuous IgG4 positivity, those with lower activation of lectin and alternative pathways would still more probably achieve CR.

  3. The galactophilic lectin (PA-IL, gene LecA) from Pseudomonas aeruginosa. Its binding requirements and the localization of lectin receptors in various mouse tissues

    DEFF Research Database (Denmark)

    Kirkeby, Svend; Hansen, Axel K; d'Apice, Anthony

    2006-01-01

    . aeruginosa lectin were compared with the results obtained using an isolectin from the legume shrub Griffonia simplicifolia: the GSI-134 isolectin, which is highly specific for glycans terminating in Ga1 alpha 1-R. In the wild-type mice, lectin histochemistry showed a strong capillary reaction in heart...

  4. Microgramma vacciniifolia (Polypodiaceae) fronds contain a multifunctional lectin with immunomodulatory properties on human cells.

    Science.gov (United States)

    de Siqueira Patriota, Leydianne Leite; Procópio, Thamara Figueiredo; de Santana Brito, Jéssica; Sebag, Virginie; de Oliveira, Ana Patrícia Silva; de Araújo Soares, Ana Karine; Moreira, Leyllane Rafael; de Albuquerque Lima, Thâmarah; Soares, Tatiana; da Silva, Túlio Diego; Paiva, Patrícia Maria Guedes; de Lorena, Virgínia Maria Barros; de Melo, Cristiane Moutinho Lagos; de Albuquerque, Lidiane Pereira; Napoleão, Thiago Henrique

    2017-10-01

    In this study, we report the purification and characterization of a multifunctional lectin (MvFL) from Microgramma vacciniifolia fronds as well as its immunomodulatory properties on human peripheral blood mononuclear cells (PBMCs). MvFL (pI 4.51; 54kDa) is a glycoprotein able to inhibit trypsin activity and that has sequence similarities (32% coverage) with a plant RNA-binding protein. Hemagglutinating activity of MvFL was not altered by heating at 100°C for 30min, but was reduced in alkaline pH (8.0 and 9.0). Fluorimetric analyses showed that this lectin did not undergo marked conformational changes when heated. However, the MvFL conformation changed depending on the pH. MvFL at 6.25-25μg/mL was not cytotoxic to lymphocytes present among PBMCs. The PBMCs incubated for 24h with the lectin (12.5μg/mL) showed increased TNF-α, IFN-γ, IL-6, IL-10, and nitric oxide production. MvFL also stimulated T lymphocytes from PBMCs to differentiate into CD8 + cells. The activation (indicated by CD28 expression) of these cells was also stimulated. In conclusion, MvFL is a heat-stable and multifunctional protein, with both lectin and trypsin inhibitor activities, and capable of inducing predominantly a Th1 response in human PBMCs as well as activation and differentiation of T lymphocytes. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Gene-environment interactions in multiple sclerosis: innate and adaptive immune responses to human endogenous retrovirus and herpesvirus antigens and the lectin complement activation pathway

    DEFF Research Database (Denmark)

    Christensen, Tove; Petersen, Thor; Thiel, Steffen

    2006-01-01

    -associated molecular pattern recognition: mannan-binding lectin (MBL), and MASP-2 and MASP-3. For representative MS families, we also determined herpesvirus serology for HSV-1, VZV, and EBV; and tissue typed for HLA-B, and HLA DR and DQ. In MS, a significant correlation between elevated immune reactivity to HERV-H Env...

  6. Gene-environment interactions in multiple sclerosis: Innate and adaptive immune responses to human endogenous retrovirus and herpesvirus antigens and the lectin complement activation pathway

    DEFF Research Database (Denmark)

    Christensen, Tove; Petersen, Thor; Thiel, Steffen

    2007-01-01

    -associated molecular pattern recognition: mannan-binding lectin (MBL), and MASP-2 and MASP-3. For representative MS families, we also determined herpesvirus serology for HSV-1, VZV, and EBV; and tissue typed for HLA-B, and HLA DR and DQ. In MS, a significant correlation between elevated immune reactivity to HERV-H Env...

  7. The gene for a lectin-like protein is transcriptionally activated during sexual development, but is not essential for fruiting body formation in the filamentous fungus Sordaria macrospora.

    Science.gov (United States)

    Nowrousian, Minou; Cebula, Patricia

    2005-11-03

    The filamentous fungus Sordaria macrospora forms complex three-dimensional fruiting bodies called perithecia that protect the developing ascospores and ensure their proper discharge. In previous microarray analyses, several genes have been identified that are downregulated in sterile mutants compared to the wild type. Among these genes was tap1 (transcript associated with perithecial development), a gene encoding a putative lectin homolog. Analysis of tap1 transcript levels in the wild type under conditions allowing only vegetative growth compared to conditions that lead to fruiting body development showed that tap1 is not only downregulated in developmental mutants but is also upregulated in the wild type during fruiting body development. We have cloned and sequenced a 3.2 kb fragment of genomic DNA containing the tap1 open reading frame and adjoining sequences. The genomic region comprising tap1 is syntenic to its homologous region in the closely related filamentous fungus Neurospora crassa. To determine whether tap1 is involved in fruiting body development in S. macrospora, a knockout construct was generated in which the tap1 open reading frame was replaced by the hygromycin B resistance gene hph under the control of fungal regulatory regions. Transformation of the S. macrospora wild type with this construct resulted in a tap1 deletion strain where tap1 had been replaced by the hph cassette. The knockout strain displayed no phenotypic differences under conditions of vegetative growth and sexual development when compared to the wild type. Double mutants carrying the Deltatap1 allele in several developmental mutant backgrounds were phenotypically similar to the corresponding developmental mutant strains. The tap1 transcript is strongly upregulated during sexual development in S. macrospora; however, analysis of a tap1 knockout strain shows that tap1 is not essential for fruiting body formation in S. macrospora.

  8. The gene for a lectin-like protein is transcriptionally activated during sexual development, but is not essential for fruiting body formation in the filamentous fungus Sordaria macrospora

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    Cebula Patricia

    2005-11-01

    Full Text Available Abstract Background The filamentous fungus Sordaria macrospora forms complex three-dimensional fruiting bodies called perithecia that protect the developing ascospores and ensure their proper discharge. In previous microarray analyses, several genes have been identified that are downregulated in sterile mutants compared to the wild type. Among these genes was tap1 (transcript associated with perithecial development, a gene encoding a putative lectin homolog. Results Analysis of tap1 transcript levels in the wild type under conditions allowing only vegetative growth compared to conditions that lead to fruiting body development showed that tap1 is not only downregulated in developmental mutants but is also upregulated in the wild type during fruiting body development. We have cloned and sequenced a 3.2 kb fragment of genomic DNA containing the tap1 open reading frame and adjoining sequences. The genomic region comprising tap1 is syntenic to its homologous region in the closely related filamentous fungus Neurospora crassa. To determine whether tap1 is involved in fruiting body development in S. macrospora, a knockout construct was generated in which the tap1 open reading frame was replaced by the hygromycin B resistance gene hph under the control of fungal regulatory regions. Transformation of the S. macrospora wild type with this construct resulted in a tap1 deletion strain where tap1 had been replaced by the hph cassette. The knockout strain displayed no phenotypic differences under conditions of vegetative growth and sexual development when compared to the wild type. Double mutants carrying the Δtap1 allele in several developmental mutant backgrounds were phenotypically similar to the corresponding developmental mutant strains. Conclusion The tap1 transcript is strongly upregulated during sexual development in S. macrospora; however, analysis of a tap1 knockout strain shows that tap1 is not essential for fruiting body formation in S. macrospora.

  9. The lectin pathway of complement

    DEFF Research Database (Denmark)

    Ballegaard, Vibe Cecilie Diederich; Haugaard, Anna Karen; Garred, P

    2014-01-01

    The pattern recognition molecules of the lectin complement pathway are important components of the innate immune system with known functions in host-virus interactions. This paper summarizes current knowledge of how these intriguing molecules, including mannose-binding lectin (MBL), Ficolin-1, -2......-1, -2 and -3 and CL-11 could have similar functions in HIV infection as the ficolins have been shown to play a role in other viral infections, and CL-11 resembles MBL and the ficolins in structure and binding capacity.......The pattern recognition molecules of the lectin complement pathway are important components of the innate immune system with known functions in host-virus interactions. This paper summarizes current knowledge of how these intriguing molecules, including mannose-binding lectin (MBL), Ficolin-1, -2...

  10. Application of lectins to tumor imaging radiopharmaceuticals

    International Nuclear Information System (INIS)

    Kojima, Shuji; Jay, M.

    1986-01-01

    We investigated the in vitro binding of 125 I-lectins to Ehrlich ascites tumor (EAT) cells and in vivo uptake of 125 I-lectins in Ehrlich solid tumor (EST) bearing mice. In in vitro binding assays, phaseolus vulgaris agglutinin (PHA), pisum sativum agglutinin (PSA), and concanavalia agglutinin (Con A) showed a high affinity for EAT cells. The in vivo biodistribution of 125 I-lectins showed 125 I-PSA to be significantly taken up into EST tissues 24 h postinjection. After IV injection of 125 I-PSA, uptake of the radioactivity into the tumor tissues reached a maximum at 6 h, and thereafter decreased. Rapid disappearance of the radioactivity from blood and its excretion into kidney soon after injection of 125 I-PSA were observed. When compared with the biodistribution of 67 Ga-citrate in EST bearing mice 24 h postinjection, tumor to liver (T/B), tumor to muscle (T/M), and tumor to blood (T/B) ratios were superior for 125 I-PSA. At 6 h postinjection, the T/B-ratio of 125 I-PSA was 2.5, and this value may be sufficient to enable discernable diagnostic images. Our results suggest that PSA might be a useful tumor imaging radiopharmaceutical. (orig.)

  11. A Lectin from Dioclea violacea Interacts with Midgut Surface of Lutzomyia migonei, Unlike Its Homologues, Cratylia floribunda Lectin and Canavalia gladiata Lectin

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    Juliana Montezuma Barbosa Monteiro Tínel

    2014-01-01

    Full Text Available Leishmaniasis is a vector-borne disease transmitted by phlebotomine sand fly. Susceptibility and refractoriness to Leishmania depend on the outcome of multiple interactions that take place within the sand fly gut. Promastigote attachment to sand fly midgut epithelium is essential to avoid being excreted together with the digested blood meal. Promastigote and gut sand fly surface glycans are important ligands in this attachment. The purpose of the present study was to evaluate the interaction of three lectins isolated from leguminous seeds (Diocleinae subtribe, D-glucose and D-mannose-binding, with glycans on Lutzomyia migonei midgut. To study this interaction the lectins were labeled with FITC and a fluorescence assay was performed. The results showed that only Dioclea violacea lectin (DVL was able to interact with midgut glycans, unlike Cratylia floribunda lectin (CFL and Canavalia gladiata lectin (CGL. Furthermore, when DVL was blocked with D-mannose the interaction was inhibited. Differences of spatial arrangement of residues and volume of carbohydrate recognition domain (CRD may be the cause of the fine specificity of DVL for glycans in the surface on Lu. migonei midgut. The findings in this study showed the presence of glycans in the midgut with glucose/mannose residues in its composition and these residues may be important in interaction between Lu. migonei midgut and Leishmania.

  12. Detection, purification and characterization of a lectin from freshwater green algae Spirogyra spp.

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    ANTÔNIA S. DE OLIVEIRA

    2017-08-01

    Full Text Available ABSTRACT Freshwater algae are rich sources of structurally biologically active metabolites, such as fatty acids, steroids, carotenoids and polysaccharides. Among these metabolites, lectins stand out. Lectins are proteins or glycoproteins of non-immune origin which bind to carbohydrates or glycoconjugates, without changing ligand structure. Many studies have reported on the use of Spirogyra spp. as effective bioindicators of heavy metals; however, reports on Spirogyra molecular bioprospecting are quite limited. Therefore, this study aimed to detect, isolate, purify and characterize a lectin present in the freshwater green algae Spirogyra. Presence of the lectin protein in the extract was detected by hemagglutination assays. Subsequently, the protein extract was subjected to a sugar inhibition assay to identify the lectin-specific carbohydrate. Following this, the extract was applied to a guar gum column to afford the pure lectin. The lectin was inhibited by N-acetyl-glucosamine and N-acetyl-beta-D-mannose, but more strongly by D-galactose. The apparent molecular mass of the purified lectin was evaluated by Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE. Electrophoretic analysis revealed a single protein band with an apparent molecular mass of 56 kDa. Thus, it could be concluded that a lectin was purified from Spirogyra spp.

  13. Studies on lectins. XXXII. Application of affinity electrophoresis to the study of the interaction of lectins and their derivatives with sugars.

    Science.gov (United States)

    Horejsí, V; Tichá, M; Kocourek, J

    1977-09-29

    Affinity electrophoresis was used to study the sugar binding heterogeneity of lectins or their derivatives. Commercial and demetallized preparations of concanavalin A could be resolved by affinity electrophoresis into three components with different affinity to immobilized sugar. Similarly the Vicia cracca lectin obtained by affinity chromatography behaved on affinity gels as a mixture of active and inactive molecular species. Affinity electrophoresis has shown that the nonhemagglutinating acetylated lentil lectin and photo-oxidized or sulfenylated pea lectin retain their sugar binding properties; dissociation constants of saccharide complexes of these derivatives are similar to those of native lectins. The presence of specific immobilized sugar in the affinity gel improved the resolution of isolectins from Dolichos biflorus and Ricinus communis seeds.

  14. Toxicity and Binding Profile of Lectins from the Genus Canavalia on Brine Shrimp

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    Francisco Vassiliepe Sousa Arruda

    2013-01-01

    Full Text Available Lectins are sugar-binding proteins widely distributed in nature with many biological functions. Although many lectins have a remarkable biotechnological potential, some of them can be cytotoxic. Thus, the aim of this study was to assess the toxicity of five lectins, purified from seeds of different species of Canavalia genus. In order to determine the toxicity, assays with Artemia nauplii were performed. In addition, a fluorescence assay was carried out to evaluate the binding of lectins to Artemia nauplii. In order to verify the relationship between the structure of lectins and their cytotoxic effect, structural analysis was carried out to evaluate the volume of the carbohydrate recognition domain (CRD of each lectin. The results showed that all lectins exhibited different toxicities and bound to a similar area in the digestive tract of Artemia nauplii. Concerning the structural analysis, differences in spatial arrangement and volume of CRD may explain the variation of the toxicity exhibited by each lectin. To this date, this is the first study that establishes a link between toxicity and structure of CRD from Diocleinae lectins.

  15. Lectin histochemical evaluation of glycoconjugates in dog efferent ductules.

    Science.gov (United States)

    Wakui, S; Furusato, M; Takahashi, H; Motoya, M; Ushigome, S

    1996-06-01

    Glycoconjugates in the epithelial cells of the efferent ductules in the dog were investigated using lectin histochemistry. These ductules connect the extratesticular rete with the epididymis. The epithelium of the ductules consisted both of ciliated and nonciliated cells. Whereas the apical zone of ciliated cells showed selective binding with WGA, SWGA, SNA, MAA and neuraminidase-PNA, that of nonciliated cells bound to all lectins used in the present study: WGA, SWGA, SNA, MAA, PNA, neuraminidase-PNA, RCA1, DBA and SBA. The nonciliated cells were divided into 3 types: type A cells which lacked both specific granules and vacuoles, type B cells which were characterised by a few specific apical vacuoles and many large specific granules, and type C cells which were characterised by some specific apical vacuoles and small basal granules. The specific granules and vacuoles of type B cells showed binding with WGA, SWGA and MAA. The specific granules of type C cells showed binding with WGA, SWGA, SNA, MAA, PNA and neuraminidase-PNA, while their specific vacuoles showed binding with WGA, SWGA, SNA and MAA. The Golgi zone both of ciliated and type A cells did not bind with any lectins used in this study, while type B and C cells showed similar lectin binding patterns between the Golgi zone and their specific granules. Specific lectin binding patterns revealed a different carbohydrate composition of each type of cell, indicating a biological difference between the ciliated cells and the 3 types of nonciliated cells in dog efferent ductules.

  16. Maize root lectins mediate the interaction with Herbaspirillum seropedicae via N-acetyl glucosamine residues of lipopolysaccharides.

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    Eduardo Balsanelli

    Full Text Available Herbaspirillum seropedicae is a plant growth-promoting diazotrophic betaproteobacterium which associates with important crops, such as maize, wheat, rice and sugar-cane. We have previously reported that intact lipopolysaccharide (LPS is required for H. seropedicae attachment and endophytic colonization of maize roots. In this study, we present evidence that the LPS biosynthesis gene waaL (codes for the O-antigen ligase is induced during rhizosphere colonization by H. seropedicae. Furthermore a waaL mutant strain lacking the O-antigen portion of the LPS is severely impaired in colonization. Since N-acetyl glucosamine inhibits H. seropedicae attachment to maize roots, lectin-like proteins from maize roots (MRLs were isolated and mass spectrometry (MS analysis showed that MRL-1 and MRL-2 correspond to maize proteins with a jacalin-like lectin domain, while MRL-3 contains a B-chain lectin domain. These proteins showed agglutination activity against wild type H. seropedicae, but failed to agglutinate the waaL mutant strain. The agglutination reaction was severely diminished in the presence of N-acetyl glucosamine. Moreover addition of the MRL proteins as competitors in H. seropedicae attachment assays decreased 80-fold the adhesion of the wild type to maize roots. The results suggest that N-acetyl glucosamine residues of the LPS O-antigen bind to maize root lectins, an essential step for efficient bacterial attachment and colonization.

  17. Maize root lectins mediate the interaction with Herbaspirillum seropedicae via N-acetyl glucosamine residues of lipopolysaccharides.

    Science.gov (United States)

    Balsanelli, Eduardo; Tuleski, Thalita Regina; de Baura, Valter Antonio; Yates, Marshall Geoffrey; Chubatsu, Leda Satie; Pedrosa, Fabio de Oliveira; de Souza, Emanuel Maltempi; Monteiro, Rose Adele

    2013-01-01

    Herbaspirillum seropedicae is a plant growth-promoting diazotrophic betaproteobacterium which associates with important crops, such as maize, wheat, rice and sugar-cane. We have previously reported that intact lipopolysaccharide (LPS) is required for H. seropedicae attachment and endophytic colonization of maize roots. In this study, we present evidence that the LPS biosynthesis gene waaL (codes for the O-antigen ligase) is induced during rhizosphere colonization by H. seropedicae. Furthermore a waaL mutant strain lacking the O-antigen portion of the LPS is severely impaired in colonization. Since N-acetyl glucosamine inhibits H. seropedicae attachment to maize roots, lectin-like proteins from maize roots (MRLs) were isolated and mass spectrometry (MS) analysis showed that MRL-1 and MRL-2 correspond to maize proteins with a jacalin-like lectin domain, while MRL-3 contains a B-chain lectin domain. These proteins showed agglutination activity against wild type H. seropedicae, but failed to agglutinate the waaL mutant strain. The agglutination reaction was severely diminished in the presence of N-acetyl glucosamine. Moreover addition of the MRL proteins as competitors in H. seropedicae attachment assays decreased 80-fold the adhesion of the wild type to maize roots. The results suggest that N-acetyl glucosamine residues of the LPS O-antigen bind to maize root lectins, an essential step for efficient bacterial attachment and colonization.

  18. A Lactose-Binding Lectin from the Marine Sponge Cinachyrella Apion (Cal) Induces Cell Death in Human Cervical Adenocarcinoma Cells

    Science.gov (United States)

    Rabelo, Luciana; Monteiro, Norberto; Serquiz, Raphael; Santos, Paula; Oliveira, Ruth; Oliveira, Adeliana; Rocha, Hugo; Morais, Ana Heloneida; Uchoa, Adriana; Santos, Elizeu

    2012-01-01

    Cancer represents a set of more than 100 diseases, including malignant tumors from different locations. Strategies inducing differentiation have had limited success in the treatment of established cancers. Marine sponges are a biological reservoir of bioactive molecules, especially lectins. Several animal and plant lectins were purified with antitumor activity, mitogenic, anti-inflammatory and antiviral, but there are few reports in the literature describing the mechanism of action of lectins purified from marine sponges to induce apoptosis in human tumor cells. In this work, a lectin purified from the marine sponge Cinachyrella apion (CaL) was evaluated with respect to its hemolytic, cytotoxic and antiproliferative properties, besides the ability to induce cell death in tumor cells. The antiproliferative activity of CaL was tested against HeLa, PC3 and 3T3 cell lines, with highest growth inhibition for HeLa, reducing cell growth at a dose dependent manner (0.5–10 µg/mL). Hemolytic activity and toxicity against peripheral blood cells were tested using the concentration of IC50 (10 µg/mL) for both trials and twice the IC50 for analysis in flow cytometry, indicating that CaL is not toxic to these cells. To assess the mechanism of cell death caused by CaL in HeLa cells, we performed flow cytometry and western blotting. Results showed that lectin probably induces cell death by apoptosis activation by pro-apoptotic protein Bax, promoting mitochondrial membrane permeabilization, cell cycle arrest in S phase and acting as both dependent and/or independent of caspases pathway. These results indicate the potential of CaL in studies of medicine for treating cancer. PMID:22690140

  19. A Lactose-Binding Lectin from the Marine Sponge Cinachyrella Apion (Cal Induces Cell Death in Human Cervical Adenocarcinoma Cells

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    Adriana Uchoa

    2012-03-01

    Full Text Available Cancer represents a set of more than 100 diseases, including malignant tumors from different locations. Strategies inducing differentiation have had limited success in the treatment of established cancers. Marine sponges are a biological reservoir of bioactive molecules, especially lectins. Several animal and plant lectins were purified with antitumor activity, mitogenic, anti-inflammatory and antiviral, but there are few reports in the literature describing the mechanism of action of lectins purified from marine sponges to induce apoptosis in human tumor cells. In this work, a lectin purified from the marine sponge Cinachyrella apion (CaL was evaluated with respect to its hemolytic, cytotoxic and antiproliferative properties, besides the ability to induce cell death in tumor cells. The antiproliferative activity of CaL was tested against HeLa, PC3 and 3T3 cell lines, with highest growth inhibition for HeLa, reducing cell growth at a dose dependent manner (0.5–10 µg/mL. Hemolytic activity and toxicity against peripheral blood cells were tested using the concentration of IC50 (10 µg/mL for both trials and twice the IC50 for analysis in flow cytometry, indicating that CaL is not toxic to these cells. To assess the mechanism of cell death caused by CaL in HeLa cells, we performed flow cytometry and western blotting. Results showed that lectin probably induces cell death by apoptosis activation by pro-apoptotic protein Bax, promoting mitochondrial membrane permeabilization, cell cycle arrest in S phase and acting as both dependent and/or independent of caspases pathway. These results indicate the potential of CaL in studies of medicine for treating cancer.

  20. The Lectin Complement Pathway in Patients with Necrotizing Soft Tissue Infection

    DEFF Research Database (Denmark)

    Hansen, Marco Bo; Rasmussen, Lars S; Pilely, Katrine

    2016-01-01

    BACKGROUND: Mannose-binding lectin (MBL) and ficolins are pattern recognition molecules (PRMs) that play an important role during infection through activation of the lectin complement pathway. We assessed whether plasma PRM levels were associated with mortality in patients with necrotizing soft t...

  1. Human mannose-binding lectin inhibitor prevents Shiga toxin-induced renal injury

    DEFF Research Database (Denmark)

    Ozaki, Masayuki; Kang, Yulin; Tan, Ying Siow

    2016-01-01

    Hemolytic uremic syndrome caused by Shiga toxin-producing Escherichia coli (STEC HUS) is a worldwide endemic problem, and its pathophysiology is not fully elucidated. Here we tested whether the mannose-binding lectin (MBL2), an initiating factor of lectin complement pathway activation, plays a cr...

  2. Composition of extracts of airborne grain dusts: lectins and lymphocyte mitogens.

    Science.gov (United States)

    Olenchock, S A; Lewis, D M; Mull, J C

    1986-01-01

    Airborne grain dusts are heterogeneous materials that can elicit acute and chronic respiratory pathophysiology in exposed workers. Previous characterizations of the dusts include the identification of viable microbial contaminants, mycotoxins, and endotoxins. We provide information on the lectin-like activity of grain dust extracts and its possible biological relationship. Hemagglutination of erythrocytes and immunochemical modulation by antibody to specific lectins showed the presence of these substances in extracts of airborne dusts from barley, corn, and rye. Proliferation of normal rat splenic lymphocytes in vitro provided evidence for direct biological effects on the cells of the immune system. These data expand the knowledge of the composition of grain dusts (extracts), and suggest possible mechanisms that may contribute to respiratory disease in grain workers. PMID:3709474

  3. Probing the cons and pros of lectin-induced immunomodulation: case studies for the mistletoe lectin and galectin-1.

    Science.gov (United States)

    Gabius, H J

    2001-07-01

    When imagining to monitor animal cells through a microscope with resolution at the molecular level, a salient attribute of their surfaces will be the abundance of glycan chains. They present galactosides at their termini widely extending like tentacles into the extracellular space. Their spatial accessibility and their potential for structural variability endow especially these glycan parts with capacity to act as docking points for molecular sensors (sugar receptors such as lectins). Binding and ligand clustering account for transmission of post-binding signals into the cell interior. The range of triggered activities has turned plant lectins into popular tools in cell biology and immunology. Potential for clinical application has been investigated rigorously only in recent years. As documented in vitro and in vivo for the galactoside-specific mistletoe lectin, its apparent immunomodulatory capacity reflected in upregulation of production of proinflammatory cytokines will not necessarily be clinically favorable but a double-edged sword. In fact, lectin application has been shown to stimulate tumor growth in cell lines, histocultures of human tumors and in two animal models using chemical carcinogenesis or tumor transplantation. When testing immunological effects of the endogenous lectin galectin-1, protection against disorders mediated by activated T cells came up for consideration. Elimination of these cells via CD7-dependent induction of apoptosis, and a shift to the Th2 response by the galectin, are factors to ameliorate disease states. This result encourages further efforts with other galectins. Functional redundancy, synergism, diversity or antagonism among galectins are being explored to understand the actual role of this class of endogenous lectins in inflammation. Regardless of the results of further preclinical testing for galectin-1, these two case studies break new ground in our understanding how glycans as ligands for lectins convey reactivity to

  4. Bauhinia variegata var. variegata lectin: isolation, characterization, and comparison.

    Science.gov (United States)

    Chan, Yau Sang; Ng, Tzi Bun

    2015-01-01

    Bauhinia variegata var. variegata seeds are rich in proteins. Previously, one of the major storage proteins of the seeds was found to be a trypsin inhibitor that possessed various biological activities. By using another purification protocol, a glucoside- and galactoside-binding lectin that demonstrated some differences from the previously reported B. variegata lectin could be isolated from the seeds. It involved affinity chromatography on Affi-gel blue gel, ion exchange chromatography on Q-Sepharose and Mono Q, and also size exclusion chromatography on Superdex 75. The lectin was not retained on Affi-gel blue gel but interacted with Q-Sepharose. The lectin was a 64-kDa protein with two 32-kDa subunits. It had low thermostability (stable up to 50 °C) and moderate pH stability (stable in pH 3-10). It exhibited anti-proliferative activity on nasopharyngeal carcinoma HONE1 cells with an IC50 of 12.8 μM after treatment for 48 h. It also slightly inhibited the growth of hepatoma HepG2 cells. The lectin may have potential in aiding cancer treatments.

  5. Interaction of lectins with membrane receptors on erythrocyte surfaces.

    Science.gov (United States)

    Sung, L A; Kabat, E A; Chien, S

    1985-08-01

    The interactions of human genotype AO erythrocytes (red blood cells) (RBCs) with N-acetylgalactosamine-reactive lectins isolated from Helix pomatia (HPA) and from Dolichos biflorus (DBA) were studied. Binding curves obtained with the use of tritium-labeled lectins showed that the maximal numbers of lectin molecules capable of binding to human genotype AO RBCs were 3.8 X 10(5) and 2.7 X 10(5) molecules/RBC for HPA and DBA, respectively. The binding of one type of lectin may influence the binding of another type. HPA was found to inhibit the binding of DBA, but not vice versa. The binding of HPA was weakly inhibited by a beta-D-galactose-reactive lectin isolated from Ricinus communis (designated RCA1). Limulus polyphemus lectin (LPA), with specificity for N-acetylneuraminic acid, did not influence the binding of HPA but enhanced the binding of DBA. About 80% of LPA receptors (N-acetylneuraminic acid) were removed from RBC surfaces by neuraminidase treatment. Neuraminidase treatment of RBCs resulted in increases of binding of both HPA and DBA, but through different mechanisms. An equal number (7.6 X 10(5) of new HPA sites were generated on genotypes AO and OO RBCs by neuraminidase treatment, and these new sites accounted for the enhancement (AO cells) and appearance (OO cells) of hemagglutinability by HPA. Neuraminidase treatment did not generate new DBA sites, but increased the DBA affinity for the existing receptors; as a result, genotype AO cells increased their hemagglutinability by DBA, while OO cells remained unagglutinable. The use of RBCs of different genotypes in binding assays with 3H-labeled lectins of known specificities provides an experimental system for studying cell-cell recognition and association.

  6. Interleukin 2 secretion by lectin-activated human blood lymphocytes is markedly augmented by vascular endothelial cells

    International Nuclear Information System (INIS)

    Guinan, E.C.; Pober, J.S.

    1986-01-01

    Since the initial interaction (and possible activation) of a blood borne T lymphocyte involves contact with the endothelial lining of the vasculature at the site of an immune response, the authors have examined the effect of cultured human endothelial cells (HEC) upon polyclonal T cell activation. Addition of 10 4 HEC to 10 4 -10 5 peripheral blood lymphocytes (PBL) stimulated with phytohemagglutinin (PHA, 0.3-10 μg/ml) leads to marked augmentation of interleukin 2 (IL-2) production. The relative increase in IL-2 (mean of 3 expts. +/- SEM) is present at 24 h (5.8 fold +/- 1.5) and become more marked at 48 h (12.6 fold +/- 3.5) and 72 h (18.5 fold +/- 3.7). This relative enhancement is greater for HEC added to 10 4 than 10 5 PBL and is also greater when 10 4 rather than 2 x 10 3 HEC are added to a given number of PBL. This increased IL-2 concentration has two biological consequences. First, at suboptimal PHA doses or at low PBL number, PBL proliferation as measured by 3 H-thymidine incorporation is increased up to two fold. Second, the phenotype of the proliferating cells appears altered, including a decrease in mean density of IL-2 receptor. The authors hypothesize that such modulation of the concentration of locally produced IL-2 may play a key role in the nature of an immune response, influencing both its magnitude and the functional profile of the activated and amplified effector cells

  7. Structure predictions of two Bauhinia variegata lectins reveal patterns of C-terminal properties in single chain legume lectins.

    Science.gov (United States)

    Moreira, Gustavo M S G; Conceição, Fabricio R; McBride, Alan J A; Pinto, Luciano da S

    2013-01-01

    Bauhinia variegata lectins (BVL-I and BVL-II) are single chain lectins isolated from the plant Bauhinia variegata. Single chain lectins undergo post-translational processing on its N-terminal and C-terminal regions, which determines their physiological targeting, carbohydrate binding activity and pattern of quaternary association. These two lectins are isoforms, BVL-I being highly glycosylated, and thus far, it has not been possible to determine their structures. The present study used prediction and validation algorithms to elucidate the likely structures of BVL-I and -II. The program Bhageerath-H was chosen from among three different structure prediction programs due to its better overall reliability. In order to predict the C-terminal region cleavage sites, other lectins known to have this modification were analysed and three rules were created: (1) the first amino acid of the excised peptide is small or hydrophobic; (2) the cleavage occurs after an acid, polar, or hydrophobic residue, but not after a basic one; and (3) the cleavage spot is located 5-8 residues after a conserved Leu amino acid. These rules predicted that BVL-I and -II would have fifteen C-terminal residues cleaved, and this was confirmed experimentally by Edman degradation sequencing of BVL-I. Furthermore, the C-terminal analyses predicted that only BVL-II underwent α-helical folding in this region, similar to that seen in SBA and DBL. Conversely, BVL-I and -II contained four conserved regions of a GS-I association, providing evidence of a previously undescribed X4+unusual oligomerisation between the truncated BVL-I and the intact BVL-II. This is the first report on the structural analysis of lectins from Bauhinia spp. and therefore is important for the characterisation C-terminal cleavage and patterns of quaternary association of single chain lectins.

  8. Studies on murine plasmocytoma treatment with mistletoe lectin I

    International Nuclear Information System (INIS)

    Raabe, F.; Storch, H.

    1987-01-01

    Mistletoe lectin I was tested in vivo and in vitro for its cytotoxic activity against murine plasmacytoma cells P3/X63-Ag8. As a result of this treatment, 30 to 60% of the BALB/c mice developed complete tumor regressions. 83% of the mice treated with mistletoe lectin I were resistant to viable tumor cell challenge after 100 days. The cytotoxic activity in vitro tested by 3 H-thymidine incorporation into P3/X63-Ag8 cells was very high. The rate was markedly reduced at concentrations up to 0.07 ng/ml. (author)

  9. The immunomodulatory effect of plant lectins: a review with emphasis on ArtinM properties.

    Science.gov (United States)

    Souza, Maria A; Carvalho, Fernanda C; Ruas, Luciana P; Ricci-Azevedo, Rafael; Roque-Barreira, Maria Cristina

    2013-10-01

    Advances in the glycobiology and immunology fields have provided many insights into the role of carbohydrate-protein interactions in the immune system. We aim to present a comprehensive review of the effects that some plant lectins exert as immunomodulatory agents, showing that they are able to positively modify the immune response to certain pathological conditions, such as cancer and infections. The present review comprises four main themes: (1) an overview of plant lectins that exert immunomodulatory effects and the mechanisms accounting for these activities; (2) general characteristics of the immunomodulatory lectin ArtinM from the seeds of Artocarpus heterophyllus; (3) activation of innate immunity cells by ArtinM and consequent induction of Th1 immunity; (4) resistance conferred by ArtinM administration in infections with intracellular pathogens, such as Leishmania (Leishmania) major, Leishmania (Leishmania) amazonensis, and Paracoccidioides brasiliensis. We believe that this review will be a valuable resource for more studies in this relatively neglected area of research, which has the potential to reveal carbohydrate targets for novel prophylactic and therapeutic strategies.

  10. Lectins and their application to clinical microbiology.

    OpenAIRE

    Slifkin, M; Doyle, R J

    1990-01-01

    Lectins are generally associated with plant or animal components, selectively bind carbohydrates, and interact with procaryotic and eucaryotic cells. Lectins have various specificities that are associated with their ability to interact with acetylaminocarbohydrates, aminocarbohydrates, sialic acids, hexoses, pentoses, and as other carbohydrates. Microbial surfaces generally contain many of the sugar residues that react with lectins. Lectins are presently used in the clinical laboratory to typ...

  11. Lectin histochemistry of 1,2-dimethylhydrazine-induced rat colon neoplasia.

    Science.gov (United States)

    Freeman, H J

    1983-10-01

    Lectins linked to fluorescein were used as carbohydrate probes to examine the goblet cell mucin and epithelial cell surface glycoconjugate alterations in an experimental rodent model of colonic neoplasia induced with parenteral 1,2-dimethylhydrazine dihydrochloride. Lectins derived from Triticum vulgare (WGA), Ricinus communis (RCA1), and Limulus polyphemus (LPA) showed reduced labeling of goblet cell mucin in these tumors, while binding with peanut lectin from Arachis hypogaea (PNA), a lectin ordinarily failing to bind to mucin in normal colon, was positive. In addition, RCA1 and LPA showed increased cell surface labeling of neoplastic epithelial cells. Finally, alterations were observed in lectin binding to "transitional" colonic mucosa adjacent to colonic tumors from carcinogen-treated rats. These findings indicate that significant alterations in both membrane and mucin glycoconjugates occur in colonic tumors and mucosa adjacent to tumors in a chemically induced experimental animal model of human colon cancer.

  12. C-Type Lectin-Like Receptor 2 Suppresses AKT Signaling and Invasive Activities of Gastric Cancer Cells by Blocking Expression of Phosphoinositide 3-Kinase Subunits.

    Science.gov (United States)

    Wang, Lan; Yin, Jie; Wang, Xuefei; Shao, Miaomiao; Duan, Fangfang; Wu, Weicheng; Peng, Peike; Jin, Jing; Tang, Yue; Ruan, Yuanyuan; Sun, Yihong; Gu, Jianxin

    2016-05-01

    C-type lectin-like receptor 2 (CLEC2) is a transmembrane receptor expressed on platelets and several hematopoietic cells. CLEC2 regulates platelet aggregation and the immune response. We investigated its expression and function in normal and transformed gastric epithelial cells from human tissues. We performed tissue microarray analyses of gastric carcinoma samples collected from 96 patients who underwent surgery at Zhongshan Hospital of Fudan University in Shanghai, China and performed real-time polymerase chain reaction assays from an independent group of 60 patients; matched nontumor gastric mucosa tissues were used as the control. Full-length and mutant forms of CLEC2 were expressed in gastric cancer cell line (MGC80-3), or CLEC2 protein was knocked down using small-hairpin RNAs in gastric cancer cell lines (NCI-N87 and AGS). CLEC2 signaling was stimulated by incubation of cells with recombinant human podoplanin or an antibody agonist of CLEC2; cell migration and invasion were assessed by transwell and wound-healing assays. Immunoblot, immunofluorescence microscopy, and real-time polymerase chain reaction assays were used to measure expression of markers of the epithelial to mesenchymal transition and activation of signaling pathways. Immunoprecipitation experiments were performed with an antibody against spleen tyrosine kinase (SYK). Cells were injected into lateral tail vein of BALB/C nude mice; some mice were also given injections of the phosphoinositide 3-kinase (PI3K) inhibitor LY294002. Lung and liver tissues were collected and analyzed for metastases. Levels of CLEC2 were higher in nontumor gastric mucosa (control) than in gastric tumor samples. Levels of CLEC2 protein in gastric tumor tissues correlated with depth of tumor invasion, metastasis to lymph node, tumor TNM stage, and 5-year survival of patients. Activation of CLEC2 in gastric cancer cells reduced their invasive activities in vitro and expression of epithelial to mesenchymal transition

  13. C-type lectins do not act as functional receptors for filovirus entry into cells

    Energy Technology Data Exchange (ETDEWEB)

    Matsuno, Keita; Nakayama, Eri; Noyori, Osamu [Department of Global Epidemiology, Hokkaido University Research Center for Zoonosis Control, Sapporo (Japan); Marzi, Andrea; Ebihara, Hideki [Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT (United States); Irimura, Tatsuro [Graduate School of Pharmaceutical Science, University of Tokyo, Tokyo (Japan); Feldmann, Heinz [Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT (United States); Takada, Ayato, E-mail: atakada@czc.hokudai.ac.jp [Department of Global Epidemiology, Hokkaido University Research Center for Zoonosis Control, Sapporo (Japan)

    2010-12-03

    Research highlights: {yields} Filovirus glycoprotein (GP) having a deficient receptor binding region were generated. {yields} Mutant GPs mediated virus entry less efficiently than wild-type GP. {yields} Mutant GPs bound to C-type lectins but not mediated entire steps of cellular entry. {yields} C-type lectins do not independently mediate filovirus entry into cells. {yields} Other molecule(s) are required for C-type lectin-mediated entry of filoviruses. -- Abstract: Cellular C-type lectins have been reported to facilitate filovirus infection by binding to glycans on filovirus glycoprotein (GP). However, it is not clearly known whether interaction between C-type lectins and GP mediates all the steps of virus entry (i.e., attachment, internalization, and membrane fusion). In this study, we generated vesicular stomatitis viruses pseudotyped with mutant GPs that have impaired structures of the putative receptor binding regions and thus reduced ability to infect the monkey kidney cells that are routinely used for virus propagation. We found that infectivities of viruses with the mutant GPs dropped in C-type lectin-expressing cells, parallel with those in the monkey kidney cells, whereas binding activities of these GPs to the C-type lectins were not correlated with the reduced infectivities. These results suggest that C-type lectin-mediated entry of filoviruses requires other cellular molecule(s) that may be involved in virion internalization or membrane fusion.

  14. Purification and characterization of liver lectins from a lizard, Sceloporus spinosus.

    Science.gov (United States)

    Fenton, N Bertha; Arreguín, L Barbarin; Méndez, C Fausto; Arreguín, E Roberto

    2004-05-01

    This study discusses the purification of soluble beta-galactose lectins obtained from the lizard liver of Sceloporus spinosus. The first lectin named lizard hepatic lectin-1 (LHL-1) presented a molecular weight of 31,750, with an isoelectric point of 4.25. The highest specific hemagglutinating activity was achieved using human blood type A1: N-acetylgalactosamine (GalNAc)-galactose (Gal)-fucose (Fuc). Carbohydrate inhibition assays indicated a higher lectin specificity for GalNAc. For LHL-2 the molecular weight obtained was 23,850 with an isoelectric point of 3.25. The highest carbohydrate specificity was observed for Gal. These lizard hepatic lectins are similar to the mammal hepatic lectins previously reported. However, it is different from the alligator hepatic lectin (AHL). The homology analyses of LHL-1 resulted in 100% identity with the Steroidogenic acute regulatory protein (StAR), while LHL-2 was similar to adenylate kinase (75% identity). We suggest that these liver lectins are related to the inherent functions of liver previously reported.

  15. C-type lectins do not act as functional receptors for filovirus entry into cells

    International Nuclear Information System (INIS)

    Matsuno, Keita; Nakayama, Eri; Noyori, Osamu; Marzi, Andrea; Ebihara, Hideki; Irimura, Tatsuro; Feldmann, Heinz; Takada, Ayato

    2010-01-01

    Research highlights: → Filovirus glycoprotein (GP) having a deficient receptor binding region were generated. → Mutant GPs mediated virus entry less efficiently than wild-type GP. → Mutant GPs bound to C-type lectins but not mediated entire steps of cellular entry. → C-type lectins do not independently mediate filovirus entry into cells. → Other molecule(s) are required for C-type lectin-mediated entry of filoviruses. -- Abstract: Cellular C-type lectins have been reported to facilitate filovirus infection by binding to glycans on filovirus glycoprotein (GP). However, it is not clearly known whether interaction between C-type lectins and GP mediates all the steps of virus entry (i.e., attachment, internalization, and membrane fusion). In this study, we generated vesicular stomatitis viruses pseudotyped with mutant GPs that have impaired structures of the putative receptor binding regions and thus reduced ability to infect the monkey kidney cells that are routinely used for virus propagation. We found that infectivities of viruses with the mutant GPs dropped in C-type lectin-expressing cells, parallel with those in the monkey kidney cells, whereas binding activities of these GPs to the C-type lectins were not correlated with the reduced infectivities. These results suggest that C-type lectin-mediated entry of filoviruses requires other cellular molecule(s) that may be involved in virion internalization or membrane fusion.

  16. Mannan-binding lectin and mannan-binding lectin-associated serine protease 2 in acute pancreatitis

    DEFF Research Database (Denmark)

    Novovic, Srdan; Andersen, Anders; Ersbøll, Annette Kjær

    2011-01-01

    Complement activation may play a prominent role in acute pancreatitis (AP). Mannan-binding lectin (MBL) and MBL-associated serine protease 2 (MASP-2) participate in complement activation. The objective of the present study was to evaluate the role of MBL and MASP-2 as markers in AP with regard...

  17. An active principle of Nigella sativa L., thymoquinone, showing significant antimicrobial activity against anaerobic bacteria.

    Science.gov (United States)

    Randhawa, Mohammad Akram; Alenazy, Awwad Khalaf; Alrowaili, Majed Gorayan; Basha, Jamith

    2017-01-01

    Thymoquinone (TQ) is the major active principle of Nigella sativa seed (black seed) and is known to control many fungi, bacteria, and some viruses. However, the activity of TQ against anaerobic bacteria is not well demonstrated. Anaerobic bacteria can cause severe infections, including diarrhea, aspiration pneumonia, and brain abscess, particularly in immunodeficient individuals. The present study aimed to investigate the in vitro antimicrobial activity of TQ against some anaerobic pathogens in comparison to metronidazole. Standard, ATCC, strains of four anaerobic bacteria ( Clostridium difficile , Clostridium perfringens , Bacteroides fragilis , and Bacteroides thetaiotaomicron ), were initially isolated on special Brucella agar base (with hemin and vitamin K). Then, minimum inhibitory concentrations (MICs) of TQ and metronidazole were determined against these anaerobes when grown in Brucella agar, using serial agar dilution method according to the recommended guidelines for anaerobic organisms instructed by the Clinical and Laboratory Standards Institute. TQ showed a significant antimicrobial activity against anaerobic bacteria although much weaker than metronidazole. MICs of TQ and metronidazole against various anaerobic human pathogens tested were found to be between 10-160 mg/L and 0.19-6.25 mg/L, respectively. TQ controlled the anaerobic human pathogenic bacteria, which supports the use of N. sativa in the treatment of diarrhea in folk medicine. Further investigations are in need for determination of the synergistic effect of TQ in combination with metronidazole and the activity of derivatives of TQ against anaerobic infections.

  18. Biological role of lectins: A review

    Directory of Open Access Journals (Sweden)

    K Kiran Kumar

    2012-01-01

    Full Text Available Lectins comprise a stracturally vary diverse class of proteins charecterized by their ability to selectively bind carbohydrate moieties of the glycoproteins of the cell surface. Lectins may be derived from plants, microbial or animal sources and may be soluble or membrane bound. Lectins is a tetramer made up of four nearly identical subunits. In human, lectins have been reported to cause food poisoning, hemolytic anemia, jaundice, digestive distress, protein and carbohydrate malabsorption and type I allergies. The present review focuses on the classification, structures, biological significance and application of lectins.

  19. Evaluation of glycophenotype in breast cancer by quantum dot-lectin histochemistry

    Directory of Open Access Journals (Sweden)

    Andrade CG

    2013-12-01

    Full Text Available Camila G Andrade,1 Paulo E Cabral Filho,2 Denise PL Tenório,3 Beate S Santos,4 Eduardo IC Beltrão,1 Adriana Fontes,2 Luiz B Carvalho Jr1 1Keizo Asami Immunopathology Laboratory, 2Biophysics and Radiobiology Department, 3Fundamental Chemistry Department, 4Pharmaceutical Science Department, Federal University of Pernambuco, Recife, Pernambuco, Brazil Abstract: Cell surface glycoconjugates play an important role in differentiation/dedifferentiation processes and lectins are employed to evaluate them by several methodologies. Fluorescent probes are considered a valuable tool because of their ability to provide a particular view, and are more detailed and sensitive in terms of cell structure and molecular content. The aim of this study was to evaluate and compare the expression and distribution of glycoconjugates in normal human breast tissue, and benign (fibroadenoma, and malignantly transformed (invasive ductal carcinoma breast tissues. For this, we used mercaptosuccinic acid-coated Cadmium Telluride (CdTe quantum dots (QDs conjugated with concanavalin A (Con A or Ulex europaeus agglutinin I (UEA I lectins to detect α-D-glucose/mannose and L-fucose residues, respectively. The QD-lectin conjugates were evaluated by hemagglutination activity tests and carbohydrate inhibition assays, and were found to remain functional, keeping their fluorescent properties and carbohydrate recognition ability. Fluorescence images showed that different regions of breast tissue expressed particular types of carbohydrates. While the stroma was preferentially and intensely stained by QD-Con A, ductal cells were preferentially labeled by QD-UEA I. These results indicate that QD-lectin conjugates can be used as molecular probes and can help to elucidate the glycoconjugate profile in biological processes. Keywords: nanoparticles, concanavalin A, Ulex europaeus, carbohydrates, mammary tissues

  20. Combretum lanceolatum flowers extract shows antidiabetic activity through activation of AMPK by quercetin

    Directory of Open Access Journals (Sweden)

    Carlos Roberto Porto Dechandt

    2012-12-01

    Full Text Available The present study evaluated the antidiabetic activity of the Combretum lanceolatum Pohl ex Eichler, Combretaceae, flowers extract (ClEtOH in diabetic rats. Streptozotocin-diabetic rats were divided into four groups: diabetic control, diabetic treated with 500 mg/kg of metformin and diabetic treated with 250 or 500 mg/kg of ClEtOH for 21 days. The treatment of diabetic rats with 500 mg/kg of ClEtOH promoted an increase in the weight of liver, white adipose tissues and skeletal muscles, improving body weight gain. Diabetic rats treated with 500 mg/kg of ClEtOH also presented reduction in glycemia, glycosuria and urinary urea levels, and increase in liver glycogen content. HPLC chromatogram showed that quercetin is the major compound in the extract. The phosphorylation levels of adenosine monophosphate-activated protein kinase were increased in liver slices incubated in vitro with 50 µg/mL of ClEtOH, similarly to the incubation with metformin (50 µg/mL or quercetin (10 µg/mL. The antihyperglycemic effect of ClEtOH was similar to that of metformin and appears to be through inhibition of gluconeogenesis, since urinary urea was reduced and skeletal muscle mass was increased. These data indicate that the antidiabetic activity of the Combretum lanceolatum extract could be mediated, at least in part, through activation of adenosine monophosphateactivated protein kinase by quercetin.

  1. Radiation enhances shelf life of Nendra bananas without changing the lectin content of raw and steamed Nendra banana

    International Nuclear Information System (INIS)

    Coelho, Neil Renault; Nivas, Shashikiran; D'Souza, L.

    2016-01-01

    Our study shows that the shelf life of bananas is increased with low doses of radiation (300 Gy, 400 Gy, 500 Gy). However, there is no decrease in the lectin content. This improves the keeping quality of nendra bananas without affecting their lectin content. Hence, radiation can be used safely for the bananas distributed to HIV children. The present study was also to compare the lectin content of raw and steamed Nendra bananas with the gamma irradiated bananas

  2. Chlropyrifos-methyl shows anti-androgenic activity without estrogenic activity in rats

    International Nuclear Information System (INIS)

    Kang, Hwan Goo; Jeong, Sang Hee; Cho, Joon Hyoung; Kim, Dong Gyu; Park, Jong Myung; Cho, Myung Haing

    2004-01-01

    Chlorpyrifos-methyl (CPM), an organophosphate insecticide, widely used for grain storage and agriculture, has been suspected as endocrine disrupter by a few in vitro studies. This study was performed to investigate the (anti-) estrogenicity and (anti-) androgenicity of CPM in vivo using immature rat uterotrophic assay and rat Hershberger assay. CPM with or without 17β-estradiol were administered to 20 days old female rats to investigate its (anti-) estrogenic activity. Uterine and vaginal weight, uterine epithelial cell height were not affected by the treatment of CPM (2, 10, 50, 250 mg/kg). CPM 250 mg/kg potentiated relative vagina weight in 17β-estradiol treated immature female rats without any changing of uterine weight. Relative liver weight was increased with decrease of body weight by CPM 250 mg/kg treatment. Uterine cell proliferation tested with bromodeoxyuridine labeling index was not observed in CPM treated rats. CPM with or without testosterone propionate were administered to castrated rat of 51 days old for 10 days to investigate the (anti-)androgenic activity,. The weight of relative and absolute androgen-dependent accessory sex organs; seminal vesicle with coagulating glands (SV/CG), ventral prostate gland (VP), glans penis (GP), levator ani plus bulbocarvernosus muscle (LABC) and Cowper's gland (CG,) were unchanged by the treatment of CPM alone. While CPM induced the increase of relative adrenal gland weight, CPM 50 mg/kg decreased the weights of CV/CG, VP, CG and LABC without change of GP without changing of GP when it was treated with TP. In conclusion, CPM dose not show estrogenic and anti-estrogenic activity in immature female rats, but it represents anti-androgenic activity by inhibition of the TP-stimulated increase of the weight of accessory sex organs

  3. Lectindb: a plant lectin database.

    Science.gov (United States)

    Chandra, Nagasuma R; Kumar, Nirmal; Jeyakani, Justin; Singh, Desh Deepak; Gowda, Sharan B; Prathima, M N

    2006-10-01

    Lectins, a class of carbohydrate-binding proteins, are now widely recognized to play a range of crucial roles in many cell-cell recognition events triggering several important cellular processes. They encompass different members that are diverse in their sequences, structures, binding site architectures, quaternary structures, carbohydrate affinities, and specificities as well as their larger biological roles and potential applications. It is not surprising, therefore, that the vast amount of experimental data on lectins available in the literature is so diverse, that it becomes difficult and time consuming, if not impossible to comprehend the advances in various areas and obtain the maximum benefit. To achieve an effective use of all the data toward understanding the function and their possible applications, an organization of these seemingly independent data into a common framework is essential. An integrated knowledge base ( Lectindb, http://nscdb.bic.physics.iisc.ernet.in ) together with appropriate analytical tools has therefore been developed initially for plant lectins by collating and integrating diverse data. The database has been implemented using MySQL on a Linux platform and web-enabled using PERL-CGI and Java tools. Data for each lectin pertain to taxonomic, biochemical, domain architecture, molecular sequence, and structural details as well as carbohydrate and hence blood group specificities. Extensive links have also been provided for relevant bioinformatics resources and analytical tools. Availability of diverse data integrated into a common framework is expected to be of high value not only for basic studies in lectin biology but also for basic studies in pursuing several applications in biotechnology, immunology, and clinical practice, using these molecules.

  4. Lectin complement pathway gene profile of the donor and recipient does not influence graft outcome after kidney transplantation.

    NARCIS (Netherlands)

    Damman, J.; Kok, J.L.; Snieder, H.; Leuvenink, H.G.; Goor, H. van; Hillebrands, J.L.; Dijk, M.C.R.F. van; Hepkema, B.G.; Reznichenko, A.; Born, J. van den; Borst, M.H. de; Bakker, S.J.; Navis, G.J.; Ploeg, R.J.; Seelen, M.A.

    2012-01-01

    In kidney transplantation, complement activation was found to be induced by donor brain death, renal ischemia-reperfusion injury and allograft rejection. There are three known pathways of complement activation: the classical, lectin and the alternative pathway. The lectin complement pathway can be

  5. Lectin-Like Molecules of Lactobacillus rhamnosus GG Inhibit Pathogenic Escherichia coli and Salmonella Biofilm Formation

    Science.gov (United States)

    Petrova, Mariya I.; Imholz, Nicole C. E.; Verhoeven, Tine L. A.; Balzarini, Jan; Van Damme, Els J. M.; Schols, Dominique; Vanderleyden, Jos; Lebeer, Sarah

    2016-01-01

    Objectives Increased antibiotic resistance has catalyzed the research on new antibacterial molecules and alternative strategies, such as the application of beneficial bacteria. Since lectin molecules have unique sugar-recognizing capacities, and pathogens are often decorated with sugars that affect their survival and infectivity, we explored whether lectins from the probiotic strain Lactobacillus rhamnosus GG have antipathogenic properties. Methods The genome sequence of L. rhamnosus GG was screened for the presence of lectin-like proteins. Two genes, LGG_RS02780 and LGG_RS02750, encoding for polypeptides with an N-terminal conserved L-type lectin domain were detected and designated Llp1 (lectin-like protein 1) and Llp2. The capacity of Llp1 and Llp2 to inhibit biofilm formation of various pathogens was investigated. Sugar specificity was determined by Sepharose beads assays and glycan array screening. Results The isolated lectin domains of Llp1 and Llp2 possess pronounced inhibitory activity against biofilm formation by various pathogens, including clinical Salmonella species and uropathogenic E. coli, with Llp2 being more active than Llp1. In addition, sugar binding assays with Llp1 and Llp2 indicate specificity for complex glycans. Both proteins are also involved in the adhesion capacity of L. rhamnosus GG to gastrointestinal and vaginal epithelial cells. Conclusions Lectins isolated from or expressed by beneficial lactobacilli could be considered promising bio-active ingredients for improved prophylaxis of urogenital and gastrointestinal infections. PMID:27537843

  6. Lectin-Like Molecules of Lactobacillus rhamnosus GG Inhibit Pathogenic Escherichia coli and Salmonella Biofilm Formation.

    Science.gov (United States)

    Petrova, Mariya I; Imholz, Nicole C E; Verhoeven, Tine L A; Balzarini, Jan; Van Damme, Els J M; Schols, Dominique; Vanderleyden, Jos; Lebeer, Sarah

    2016-01-01

    Increased antibiotic resistance has catalyzed the research on new antibacterial molecules and alternative strategies, such as the application of beneficial bacteria. Since lectin molecules have unique sugar-recognizing capacities, and pathogens are often decorated with sugars that affect their survival and infectivity, we explored whether lectins from the probiotic strain Lactobacillus rhamnosus GG have antipathogenic properties. The genome sequence of L. rhamnosus GG was screened for the presence of lectin-like proteins. Two genes, LGG_RS02780 and LGG_RS02750, encoding for polypeptides with an N-terminal conserved L-type lectin domain were detected and designated Llp1 (lectin-like protein 1) and Llp2. The capacity of Llp1 and Llp2 to inhibit biofilm formation of various pathogens was investigated. Sugar specificity was determined by Sepharose beads assays and glycan array screening. The isolated lectin domains of Llp1 and Llp2 possess pronounced inhibitory activity against biofilm formation by various pathogens, including clinical Salmonella species and uropathogenic E. coli, with Llp2 being more active than Llp1. In addition, sugar binding assays with Llp1 and Llp2 indicate specificity for complex glycans. Both proteins are also involved in the adhesion capacity of L. rhamnosus GG to gastrointestinal and vaginal epithelial cells. Lectins isolated from or expressed by beneficial lactobacilli could be considered promising bio-active ingredients for improved prophylaxis of urogenital and gastrointestinal infections.

  7. Association of Low Ficolin-Lectin Pathway Parameters with Cardiac Syndrome X

    DEFF Research Database (Denmark)

    Horváth, Z; Csuka, Dorottya; Vargova, K

    2016-01-01

    In patients with typical angina pectoris, inducible myocardial ischaemia and macroscopically normal coronaries (cardiac syndrome X (CSX)), a significantly elevated plasma level of terminal complement complex (TCC), the common end product of complement activation, has been observed without.......003). In conclusion, in patients with typical angina and myocardial ischaemia despite macroscopically normal coronary arteries, low levels of several lectin pathway parameters were observed, indicating complement activation and consumption. Complement activation through the ficolin-lectin pathway might play a role...

  8. Tetranectin, a trimeric plasminogen-binding C-type lectin

    DEFF Research Database (Denmark)

    Holtet, T L; Graversen, Jonas Heilskov; Clemmensen, I

    1997-01-01

    -linking analysis and SDS-PAGE to be a homo-trimer in solution as are other known members of the collectin family of C-type lectins. Biochemical evidence is presented showing that an N-terminal domain encoded within exons 1 and 2 of the tetranectin gene is necessary and sufficient to govern subunit trimerization....

  9. Momordica charantia seed lectin: toxicity, bacterial agglutination and antitumor properties.

    Science.gov (United States)

    Kabir, Syed Rashel; Nabi, Md Mahamodun; Nurujjaman, Md; Abu Reza, Md; Alam, A H M Khurshid; Uz Zaman, Rokon; Khalid-Bin-Ferdaus, Khandaker Md; Amin, Ruhul; Khan, Md Masudul Hasan; Hossain, Md Anowar; Uddin, Md Salim; Mahmud, Zahid Hayat

    2015-03-01

    In last three decades, several studies were carried out on the D-galactose-specific lectin of Momordica charantia seeds (MCL). In the present study, in vitro growth inhibition (8-23 %) at different concentrations (6-24 μg/ml) of MCL was observed against Ehrlich ascites carcinoma (EAC) cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. MCL also showed 28, 45, and 75 % growth inhibitions against EAC cells when administered 1.2, 2.0, and 2.8 mg/kg/day (i.p.), respectively for five consequent days in vivo in mice. After lectin treatment, the level of red blood cell and hemoglobin was increased significantly with the decrease of white blood cell and maintained the normal level when compared with EAC-bearing control and normal mice without EAC cells. Although MCL caused cell cycle arrest at G0/G1 phase of EAC cells, any irregular shape or apoptotic morphological alterations in the lectin-treated EAC cells was not observed by an optical and fluorescence microscope. Lectin showed toxicity against brine shrimp nauplii with an LC50 value of 49.7 μg/ml. Four out of seven pathogenic bacteria were agglutinated by MCL in the absence of inhibitory sugar D-lactose/D-galactose. In conclusion, MCL showed strong cytotoxic effect and therefore can be used as a potent anticancer chemotherapeutic agent.

  10. Lectin cDNA and transgenic plants derived therefrom

    Science.gov (United States)

    Raikhel, Natasha V.

    2000-10-03

    Transgenic plants containing cDNA encoding Gramineae lectin are described. The plants preferably contain cDNA coding for barley lectin and store the lectin in the leaves. The transgenic plants, particularly the leaves exhibit insecticidal and fungicidal properties.

  11. A sperm-agglutinating lectin from seeds of Jack fruit (Artocarpus heterophyllus).

    Science.gov (United States)

    Namjuntra, P; Muanwongyathi, P; Chulavatnatol, M

    1985-04-30

    A lectin specific for N-acetylgalactosamine was isolated from seed extract of Jack fruit (Artocarpus heterophyllus) by ammonium sulfate precipitation, followed by affinity chromatography on a Affigel-galactosamine-agarose column. The lectin possessed agglutinating activities for human and rat sperm as well as human red blood cells. It was found to have Mr = 62,000 consisting of two dissimilar subunits of Mr = 18,000 and 13,000. It also cross-reacted with an antibody against the lectin of Osage Orange (Maclura pomifera).

  12. Immunologically related lectins from stems and roots of developing seedlings of Cucurbita ficifolia: purification and some properties of root and stem lectins

    Directory of Open Access Journals (Sweden)

    Irena Lorenc-Kubis

    2014-01-01

    Full Text Available Hemagglutinating activity has been found in acetate extracts from roots and stems of squash seedlings (Cucurbita ficifolia. The hemaglutinating activity changes during seeds germination and seedling development. Dot blot and Western blot techniques have shown that proteins from these vegetative tissues cross-reacted with antibodies raised against endogenous cotyledons lectin CLBa and Con A.Lectins were isolated from stems and roots of 6-day old seedlings by precipitation with ethanol, affinity chromatography on Con A-Sepharose, gel filtration on Bio-gel P100 and separated by electrophoresis on polyacrylamide gel. Three purified lectins (RLA1, RLA2, RLA3 were obtained from roots and four from stems (SLA1, SLA2, SLA3, SLA4. The purified lectins from roots and stems agglutinated all human red blood cells, but sheep erythrocytes were most sensitive to agglutination. The hemagglutination of the root lectins RLA2 and RLA3 was inhibited by a very low concentration of arabinose, while RLA1, of xylose and Ga1NAc. Arabinose and Xylose were also found to be the most effective inhibitors of all stem lectins.

  13. Presenting Precision Glycomacromolecules on Gold Nanoparticles for Increased Lectin Binding

    Directory of Open Access Journals (Sweden)

    Sophia Boden

    2017-12-01

    Full Text Available Glyco-functionalized gold nanoparticles have great potential as biosensors and as inhibitors due to their increased binding to carbohydrate-recognizing receptors such as the lectins. Here we apply previously developed solid phase polymer synthesis to obtain a series of precision glycomacromolecules that allows for straightforward variation of their chemical structure as well as functionalization of gold nanoparticles by ligand exchange. A novel building block is introduced allowing for the change of spacer building blocks within the macromolecular scaffold going from an ethylene glycol unit to an aliphatic spacer. Furthermore, the valency and overall length of the glycomacromolecule is varied. All glyco-functionalized gold nanoparticles show high degree of functionalization along with high stability in buffer solution. Therefore, a series of measurements applying UV-Vis spectroscopy, dynamic light scattering (DLS and surface plasmon resonance (SPR were performed studying the aggregation behavior of the glyco-functionalized gold nanoparticles in presence of model lectin Concanavalin A. While the multivalent presentation of glycomacromolecules on gold nanoparticles (AuNPs showed a strong increase in binding compared to the free ligands, we also observed an influence of the chemical structure of the ligand such as its valency or hydrophobicity on the resulting lectin interactions. The straightforward variation of the chemical structure of the precision glycomacromolecule thus gives access to tailor-made glyco-gold nanoparticles (glyco-AuNPs and fine-tuning of their lectin binding properties.

  14. Structure of Dioclea virgata lectin: relations between carbohydrate binding site and nitric oxide production

    International Nuclear Information System (INIS)

    Delatorre, P.; Gadelha, C.A.A.; Santi-Gadelha, T.; Nobrega, R.B.; Rocha, B.A.M.; Nascimento, K.S.; Naganao, C.S.; Sampaio, A.H.; Cavada, B.S.; Pires, A.F.; Assreuy, A.M.S.

    2012-01-01

    Full text: Lectins are proteins/glycoproteins with at least one noncatalytic domain binding reversibly to specific monosaccharides or oligosaccharides. By binding to carbohydrate moieties on the cell surface, lectins participate in a range of cellular processes without changing the properties of the carbohydrates involved. The lectin of Dioclea virgata (DvirL), both native and complexed with X-man, was submitted to X-ray diffraction analysis and the crystal structure was compared to that of other Diocleinae lectins in order to better understand differences in biological proper- ties, especially with regard to the ability of lectins to induce nitric oxide (NO) production. The DvirL diffraction analysis revealed that both the native crystal and the X-Man-complexed form are orthorhombic and belong to space group I222. The cell parameters were: a=65.4 , b=86.6 and c=90.2 (native structure), and a=61.89 , b=87.67 and c=88.78 (X-Man-complexed structure). An association was observed between the volume of the carbohydrate recognition domain (CRD), the ability to induce NO production and the relative positions of Tyr12, Arg228 and Leu99. Thus, differences in biological activity induced by Diocleinae lectins are related to the configuration of amino acid residues in the carbohydrate binding site and to the structural conformation of subsequent regions capable of influencing site-ligand interactions. In conclusion, the ability of Diocleinae lectins to induce NO production depends on CRD configuration. (author)

  15. PgTeL, the lectin found in Punica granatum juice, is an antifungal agent against Candida albicans and Candida krusei.

    Science.gov (United States)

    da Silva, Pollyanna Michelle; de Moura, Maiara Celine; Gomes, Francis Soares; da Silva Trentin, Danielle; Silva de Oliveira, Ana Patrícia; de Mello, Gabriela Souto Vieira; da Rocha Pitta, Maira Galdino; de Melo Rego, Moacyr Jesus Barreto; Coelho, Luana Cassandra Breitenbach Barroso; Macedo, Alexandre José; de Figueiredo, Regina Celia Bressan Queiroz; Paiva, Patrícia Maria Guedes; Napoleão, Thiago Henrique

    2018-03-01

    The pomegranate (Punica granatum) sarcotesta contains a chitin-binding lectin (PgTeL) with antibacterial activity against human pathogenic species. In this work, the structural stability of PgTeL was evaluated by fluorimetric analysis and the lectin was evaluated for cytotoxicity to human peripheral blood mononuclear cells (PBMCs) and antifungal activity against Candida albicans and Candida krusei. PgTeL folding was impaired when lectin was incubated at pH≥6.0. On the other hand, the lectin did not undergo unfolding even when heated at 100°C. PgTeL (1, 10, and 100μg/mL) was not cytotoxic to PBMCs. Antifungal activity was detected for C. albicans (MIC: 25μg/mL; MFC: 50μg/mL) and C. krusei (MIC and MFC of 12.5μg/mL). Treatment of yeast cells with PgTeL resulted in decrease of intracellular ATP content even at sub-inhibitory concentrations (½MIC and ¼MIC) and induced lipid peroxidation. In addition, PgTeL damaged the integrity of fungal cell wall of both species, with more pronounced effects in C. krusei. The lectin showed significant antibiofilm activity on C. albicans at sub-inhibitory concentrations (0.195 and 0.39μg/mL). In conclusion, PgTeL is an anti-Candida agent whose action mechanism involves oxidative stress, energetic collapse, damage to the cell wall and rupture of yeast cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Mannose-binding lectin (MBL2) and ficolin-2 (FCN2) polymorphisms in patients on peritoneal dialysis with staphylococcal peritonitis

    NARCIS (Netherlands)

    Meijvis, Sabine C. A.; Herpers, Bjorn L.; Endeman, Henrik; de Jong, Ben; van Hannen, Erik; van Velzen-Blad, Heleen; Krediet, Raymond T.; Struijk, Dirk G.; Biesma, Douwe H.; Bos, Willem Jan W.

    Background. Mannose-binding lectin (MBL) and ficolin-2 (FCN) are activators of the lectin pathway of complement and act as primary defences against infection. Single-nucleotide polymorphisms (SNPs) in the MBL2 and FCN2 genes influence the functionality of the proteins. Both proteins are capable of

  17. Protozoa lectins and their role in host-pathogen interactions.

    Science.gov (United States)

    Singh, Ram Sarup; Walia, Amandeep Kaur; Kanwar, Jagat Rakesh

    2016-01-01

    Lectins are proteins/glycoproteins of non-immune origin that agglutinate red blood cells, lymphocytes, fibroblasts, etc., and bind reversibly to carbohydrates present on the apposing cells. They have at least two carbohydrate binding sites and their binding can be inhibited by one or more carbohydrates. Owing to carbohydrate binding specificity of lectins, they mediate cell-cell interactions and play role in protozoan adhesion and host cell cytotoxicity, thus are central to the pathogenic property of the parasite. Several parasitic protozoa possess lectins which mediate parasite adherence to host cells based on their carbohydrate specificities. These interactions could be exploited for development of novel therapeutics, targeting the adherence and thus helpful in eradicating wide spread of protozoan diseases. The current review highlights the present state knowledge with regard to protozoal lectins with an emphasis on their haemagglutination activity, carbohydrate specificity, characteristics and also their role in pathogenesis notably as adhesion molecules, thereby aiding the pathogen in disease establishment. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Evolutionary history and stress regulation of the lectin superfamily in higher plants

    Directory of Open Access Journals (Sweden)

    Ramachandran Srinivasan

    2010-03-01

    Full Text Available Abstract Background Lectins are a class of carbohydrate-binding proteins. They play roles in various biological processes. However, little is known about their evolutionary history and their functions in plant stress regulation. The availability of full genome sequences from various plant species makes it possible to perform a whole-genome exploration for further understanding their biological functions. Results Higher plant genomes encode large numbers of lectin proteins. Based on their domain structures and phylogenetic analyses, a new classification system has been proposed. In this system, 12 different families have been classified and four of them consist of recently identified plant lectin members. Further analyses show that some of lectin families exhibit species-specific expansion and rapid birth-and-death evolution. Tandem and segmental duplications have been regarded as the major mechanisms to drive lectin expansion although retrogenes also significantly contributed to the birth of new lectin genes in soybean and rice. Evidence shows that lectin genes have been involved in biotic/abiotic stress regulations and tandem/segmental duplications may be regarded as drivers for plants to adapt various environmental stresses through duplication followed by expression divergence. Each member of this gene superfamily may play specialized roles in a specific stress condition and function as a regulator of various environmental factors such as cold, drought and high salinity as well as biotic stresses. Conclusions Our studies provide a new outline of the plant lectin gene superfamily and advance the understanding of plant lectin genes in lineage-specific expansion and their functions in biotic/abiotic stress-related developmental processes.

  19. Comparative Study of Lectin Domains in Model Species: New Insights into Evolutionary Dynamics

    Directory of Open Access Journals (Sweden)

    Sofie Van Holle

    2017-05-01

    Full Text Available Lectins are present throughout the plant kingdom and are reported to be involved in diverse biological processes. In this study, we provide a comparative analysis of the lectin families from model species in a phylogenetic framework. The analysis focuses on the different plant lectin domains identified in five representative core angiosperm genomes (Arabidopsis thaliana, Glycine max, Cucumis sativus, Oryza sativa ssp. japonica and Oryza sativa ssp. indica. The genomes were screened for genes encoding lectin domains using a combination of Basic Local Alignment Search Tool (BLAST, hidden Markov models, and InterProScan analysis. Additionally, phylogenetic relationships were investigated by constructing maximum likelihood phylogenetic trees. The results demonstrate that the majority of the lectin families are present in each of the species under study. Domain organization analysis showed that most identified proteins are multi-domain proteins, owing to the modular rearrangement of protein domains during evolution. Most of these multi-domain proteins are widespread, while others display a lineage-specific distribution. Furthermore, the phylogenetic analyses reveal that some lectin families evolved to be similar to the phylogeny of the plant species, while others share a closer evolutionary history based on the corresponding protein domain architecture. Our results yield insights into the evolutionary relationships and functional divergence of plant lectins.

  20. Lectin Histochemical Study of Cell Surface Glycoconjugate in Gastric Carcinoma Using Helix Pomatia Agglutinin

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Arab

    2010-07-01

    Full Text Available "nAltered glycosylation of proteins in cancer cells is one of the main processes responsible for anaplasia, invasion and metastatic potential of neoplastic cells. Lectins are nonimmunogenetic compounds which specifically detect certain terminal sugars of glycoconjugates. The aim of the present study was to identify the N-acetylgalactosamine (GalNac containing glycoconjugates in cancer cells in all grades of gastric carcinoma. Paraffin blocks belong to 30 patients of gastric carcinoma (10 cases from each grade was collected from pathology file of Ali-Ebn-Abitaleb Hospital in Zahedan during 2005-2007. Prepared sections (5-7μm in thickness were stained by Alcian Blue, hematoxylin and eosin (H&E and helix pomatia agglutinin (HPA conjugated lectin. Lectin diluted up to 10μg/ml in PBS (0.1M, pH=6.8. Lectin reactivity was visualized by 0.03% diaminobenzidine (DAB solution. Sections were graded according to staining intensity to lectin (0-4+. Although there was some difference for lectin staining intensity between cancer cells in different grades of gastric carcinoma, statistical analysis showed that there was only a significant difference for cancer cells reactivity between histopathological grades of II and III. The pattern of reactivity to HPA lectin were also different from all histopathological grades. It seems that in cancer cells, the amount and distribution of GalNac containing glycoconjugate differ from neoplastic cells of different histopathological grades in gastric carcinoma.

  1. Lectin Histochemical Study of Cell Surface Glycoconjugate in Gastric Carcinoma Using Helix Pomatia Agglutinin

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Arab

    2010-08-01

    Full Text Available Altered glycosylation of proteins in cancer cells is one of the main processes responsible for anaplasia, invasion and metastatic potential of neoplastic cells. Lectins are nonimmunogenetic compounds which specifically detect certain terminal sugars of glycoconjugates. The aim of the present study was to identify the N-acetylgalactosamine (GalNac containing glycoconjugates in cancer cells in all grades of gastric carcinoma. Paraffin blocks belong to 30 patients of gastric carcinoma (10 cases from each grade was collected from pathology file of Ali-Ebn-Abitaleb Hospital in Zahedan during 2005-2007. Prepared sections (5-7μm in thickness were stained by Alcian Blue, hematoxylin and eosin (H&E and helix pomatia agglutinin (HPA conjugated lectin. Lectin diluted up to 10μg/ml in PBS (0.1M, pH=6.8. Lectin reactivity was visualized by 0.03% diaminobenzidine (DAB solution. Sections were graded according to staining intensity to lectin (0-4+. Although there was some difference for lectin staining intensity between cancer cells in different grades of gastric carcinoma, statistical analysis showed that there was only a significant difference for cancer cells reactivity between histopathological grades of II and III. The pattern of reactivity to HPA lectin were also different from all histopathological grades. It seems that in cancer cells, the amount and distribution of GalNac containing glycoconjugate differ from neoplastic cells of different histopathological grades in gastric carcinoma.

  2. Quantitation of two endogenous lactose-inhibitable lectins in embryonic and adult chicken tissues

    International Nuclear Information System (INIS)

    Beyer, E.C.; Barondes, S.H.

    1982-01-01

    Two lactose-binding lectins from chicken tissues, chicken-lactose-lectin-I (CLL-I) and chicken-lactose-lectin-II (CLL-II) were quantified with a radioimmunoassay in extracts of a number of developing and adult chicken tissues. Both lectins could be measured in the same extract without separation, because they showed no significant immunological cross- reactivity. Many embryonic and adult tissues, including brain, heart, intestine, kidney, liver, lung, muscle, pancreas, and spleen, contained one or both lectins, although their concentrations differed markedly. For example, embryonic muscle, the richest source of CLL-I contained only traces of CLL-II whereas embryonic kidney, a very rich source of CLL-II contained substantial CLL-I. In both muscle and kidney, lectin levels in adulthood were much lower than in the embryonic state. In contrast, CLL-I in liver and CLL-II in intestine were 10-fold to 30-fold more concentrated in the adult than in the 15-d embryo. CLL-I and CLL-II from several tissues were purified by affinity chromatography and their identity in the various tissues was confirmed by polyacrylamide gel electrophoresis, isoelectric focusing, and peptide mapping. The results suggest that these lectins might have different functions in the many developing and adult tissues in which they are found

  3. The distribution of lectin receptor sites in human breast lesions.

    Science.gov (United States)

    Skutelsky, E; Hoenig, S; Griffel, B; Alroy, J

    1988-08-01

    Conflicting data regarding the status of A, B, H and T antigens in epithelium of normal, mastopathies, fibroadenomas and carcinomas of the breast stimulated us to re-examine the carbohydrate residues in these condition. Currently, we extended the number of carbohydrate residues studied by using ten different biotinylated lectins as probes and avidin-biotin-peroxidase complex (ABC) as a visualant. In addition, the pattern of lectin staining of cancerous cells in primary and metastatic sites was compared. In primary and metastatic breast carcinomas, lectin receptor sites were stained more intensely with Concanavalia ensiformi agglutinin (*Con A), Ricinus communis agglutinin-I (RCA-I) and wheat germ agglutinin (WGA), than in normal breast, in mastopathies or in fibroadenomas. Cryptic receptor sites for peanut agglutinin (PNA) were stained in all cases of breast carcinomas, while free PNA sites stained only in a few cases of well-differentiated carcinomas. Receptors sites for Ulex europaeus agglutinin-I (UEA-I) stained non-malignant epithelium of patients with blood group H but did not stain malignant cells. The results show significant differences in lectin-binding patterns and staining intensities between normal and non-malignant, and malignant epithelial breast cells. Furthermore, these results indicate that in malignant cells, there is an increased content of sialic acid-rich carbohydrates but not of asialylated glycoconjugates.

  4. Isolation and characterization of a novel lectin from the mushroom Armillaria luteo-virens

    International Nuclear Information System (INIS)

    Feng, K.; Liu, Q.H.; Ng, T.B.; Liu, H.Z.; Li, J.Q.; Chen, G.; Sheng, H.Y.; Xie, Z.L.; Wang, H.X.

    2006-01-01

    From the dried fruiting bodies of the mushroom Armillaria luteo-virens, a dimeric lectin with a molecular mass of 29.4 kDa has been isolated. The purification procedure involved (NH 4 ) 2 SO 4 precipitation, ion exchange chromatography on DEAE-cellulose, CM-cellulose, and Q-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The hemagglutinating activity of the lectin could not be inhibited by simple sugars but was inhibited by the polysaccharide inulin. The activity was stable up to 70 o C but was acid- and alkali-labile. Salts including FeCl 3 , AlCl 3 , and ZnCl 2 inhibited the activity whereas MgCl 2 , MnCl 2 , and CaCl 2 did not. The lectin stimulated mitogenic response of mouse splenocytes with the maximal response achieved by 1 μM lectin. Proliferation of tumor cells including MBL2 cells, HeLa cells, and L1210 cells was inhibited by the lectin with an IC 5 of 2.5, 5, and 10 μM, respectively. However, proliferation of HepG2 cells was not affected. The novel aspects of the isolated lectin include a novel N-terminal sequence, fair thermostability, acid stability, and alkali stability, together with potent mitogenic activity toward spleen cells and antiproliferative activity toward tumor cells

  5. STUDY OF AZOSPIRILLUM LECTINS INFLUENCE ON HYDROGEN PEROXIDE PRODUCTION IN WHEAT-ROOTS

    Directory of Open Access Journals (Sweden)

    Alen’kina S.A.

    2009-12-01

    Full Text Available It was found that two cell-surface lectins isolated from the nitrogen-fixing soil bacterium Azospirillum brasilense Sp7 and from its mutant defective in lectin activity, A. brasilense Sp7.2.3 can stimulate rapid formation of hydrogen peroxide, associated with an increase in the activities of oxalate oxidase and peroxidase in the roots of wheat seedlings. The most advantageous and most rapidly induced pathway of hydrogen peroxide formation was the oxidation of oxalic acid by oxalate oxidase because in this case, a 10-min treatment of the roots with the lectins at 10 µg ml-1 was sufficient. The data from this study attest that the Azospirillum lectins can act as inducers of adaptation processes in the roots of wheat seedlings.

  6. Sugar-Binding Profiles of Chitin-Binding Lectins from the Hevein Family: A Comprehensive Study

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    Yoko Itakura

    2017-05-01

    Full Text Available Chitin-binding lectins form the hevein family in plants, which are defined by the presence of single or multiple structurally conserved GlcNAc (N-acetylglucosamine-binding domains. Although they have been used as probes for chito-oligosaccharides, their detailed specificities remain to be investigated. In this study, we analyzed six chitin-binding lectins, DSA, LEL, PWM, STL, UDA, and WGA, by quantitative frontal affinity chromatography. Some novel features were evident: WGA showed almost comparable affinity for pyridylaminated chitotriose and chitotetraose, while LEL and UDA showed much weaker affinity, and DSA, PWM, and STL had no substantial affinity for the former. WGA showed selective affinity for hybrid-type N-glycans harboring a bisecting GlcNAc residue. UDA showed extensive binding to high-mannose type N-glycans, with affinity increasing with the number of Man residues. DSA showed the highest affinity for highly branched N-glycans consisting of type II LacNAc (N-acetyllactosamine. Further, multivalent features of these lectins were investigated by using glycoconjugate and lectin microarrays. The lectins showed substantial binding to immobilized LacNAc as well as chito-oligosaccharides, although the extents to which they bound varied among them. WGA showed strong binding to heavily sialylated glycoproteins. The above observations will help interpret lectin-glycoprotein interactions in histochemical studies and glyco-biomarker investigations.

  7. Low mannose-binding lectin serum levels are associated with reduced kidney graft survival

    DEFF Research Database (Denmark)

    Bay, Jakob Thaning; Sørensen, Søren S; Hansen, Jesper M

    2013-01-01

    Activation of the complement system is initiated by the alternative, the classical, or the lectin pathway. As the complement system is involved in the pathophysiology of graft rejection after kidney transplantation, we investigated the possible role of mannose-binding lectin in kidney transplanta...... immunity in maintaining kidney graft survival, but these are probably overruled by HLA immunization.Kidney International advance online publication, 21 November 2012; doi:10.1038/ki.2012.373....

  8. Cytotoxic Effects of Native and Recombinant Frutalin, a Plant Galactose-Binding Lectin, on HeLa Cervical Cancer Cells

    Directory of Open Access Journals (Sweden)

    Carla Oliveira

    2011-01-01

    Full Text Available Frutalin is the α-D-galactose-binding lectin isolated from breadfruit seeds. Frutalin was obtained from two different sources: native frutalin was purified from its natural origin, and recombinant frutalin was produced and purified from Pichia pastoris. This work aimed to study and compare the effect of native and recombinant frutalin on HeLa cervical cancer cells proliferation and apoptosis. Furthermore, the interaction between frutalin and the HeLa cells was investigated by confocal microscopy. Despite having different carbohydrate-binding affinities, native and recombinant frutalin showed an identical magnitude of cytotoxicity on HeLa cells growth (IC50~100 μg/mL and equally induced cell apoptosis. The interaction studies showed that both lectins were rapidly internalised and targeted to HeLa cell's nucleus. Altogether, these results indicate that frutalin action is not dependent on its sugar-binding properties. This study provides important information about the bioactivity of frutalin and contributes to the understanding of the plant lectins cytotoxic activity.

  9. Morphological variability, lectin binding and Na+,K+-activated adenosine triphosphatase activity of isolated Müller (glial) cells from the rabbit retina.

    Science.gov (United States)

    Reichenbach, A; Dettmer, D; Brückner, G; Neumann, M; Birkenmeyer, G

    1985-03-22

    Rabbit retinal Müller cells were isolated by means of papaine and mechanical dissociation. These cells were shown to have a well preserved morphology and to preserve viability for many hours. Intense wheat germ agglutinin binding occurs on the photoreceptor side of Müller cells, especially in the microvillous region. Rabbit retinal Müller cells have a Na+,K+-activated adenosine triphosphatase activity in the same order of magnitude as brain astroglial cells.

  10. Sugared biomaterial binding lectins: achievements and perspectives

    Czech Academy of Sciences Publication Activity Database

    Bojarová, Pavla; Křen, Vladimír

    2016-01-01

    Roč. 4, č. 8 (2016), s. 1142-1160 ISSN 2047-4830 R&D Projects: GA ČR GC15-02578J Institutional support: RVO:61388971 Keywords : C-TYPE LECTINS * AMPHIPHILIC JANUS GLYCODENDRIMERS * BIOMEDICALLY RELEVANT LECTINS Subject RIV: CE - Biochemistry Impact factor: 4.210, year: 2016

  11. Molecular Characterization and Biological Effects of a C-Type Lectin-Like Receptor in Large Yellow Croaker (Larimichthys crocea).

    Science.gov (United States)

    Ao, Jingqun; Ding, Yang; Chen, Yuanyuan; Mu, Yinnan; Chen, Xinhua

    2015-12-10

    The C-type lectin-like receptors (CTLRs) play important roles in innate immunity as one type of pattern recognition receptors. Here, we cloned and characterized a C-type lectin-like receptor (LycCTLR) from large yellow croaker Larimichthys crocea. The full-length cDNA of LycCTLR is 880 nucleotides long, encoding a protein of 215 amino acids. The deduced LycCTLR contains a C-terminal C-type lectin-like domain (CTLD), an N-terminal cytoplasmic tail, and a transmembrane region. The CTLD of LycCTLR possesses six highly conserved cysteine residues (C1-C6), a conserved WI/MGL motif, and two sugar binding motifs, EPD (Glu-Pro-Asp) and WYD (Trp-Tyr-Asp). Ca(2+) binding site 1 and 2 were also found in the CTLD. The LycCTLR gene consists of five exons and four introns, showing the same genomic organization as tilapia (Oreochromis niloticus) and guppy (Poecilia retitculata) CTLRs. LycCTLR was constitutively expressed in various tissues tested, and its transcripts significantly increased in the head kidney and spleen after stimulation with inactivated trivalent bacterial vaccine. Recombinant LycCTLR (rLycCTLR) protein produced in Escherichia coli BL21 exhibited not only the hemagglutinating activity and a preference for galactose, but also the agglutinating activity against two food-borne pathogenic bacteria E. coli and Bacillus cereus in a Ca(2+)-dependent manner. These results indicate that LycCTLR is a potential galactose-binding C-type lectin that may play a role in the antibacterial immunity in fish.

  12. Molecular Characterization and Biological Effects of a C-Type Lectin-Like Receptor in Large Yellow Croaker (Larimichthys crocea

    Directory of Open Access Journals (Sweden)

    Jingqun Ao

    2015-12-01

    Full Text Available The C-type lectin-like receptors (CTLRs play important roles in innate immunity as one type of pattern recognition receptors. Here, we cloned and characterized a C-type lectin-like receptor (LycCTLR from large yellow croaker Larimichthys crocea. The full-length cDNA of LycCTLR is 880 nucleotides long, encoding a protein of 215 amino acids. The deduced LycCTLR contains a C-terminal C-type lectin-like domain (CTLD, an N-terminal cytoplasmic tail, and a transmembrane region. The CTLD of LycCTLR possesses six highly conserved cysteine residues (C1–C6, a conserved WI/MGL motif, and two sugar binding motifs, EPD (Glu-Pro-Asp and WYD (Trp-Tyr-Asp. Ca2+ binding site 1 and 2 were also found in the CTLD. The LycCTLR gene consists of five exons and four introns, showing the same genomic organization as tilapia (Oreochromis niloticus and guppy (Poecilia retitculata CTLRs. LycCTLR was constitutively expressed in various tissues tested, and its transcripts significantly increased in the head kidney and spleen after stimulation with inactivated trivalent bacterial vaccine. Recombinant LycCTLR (rLycCTLR protein produced in Escherichia coli BL21 exhibited not only the hemagglutinating activity and a preference for galactose, but also the agglutinating activity against two food-borne pathogenic bacteria E. coli and Bacillus cereus in a Ca2+-dependent manner. These results indicate that LycCTLR is a potential galactose-binding C-type lectin that may play a role in the antibacterial immunity in fish.

  13. A chitin-binding lectin from Moringa oleifera seeds (WSMoL) impairs the digestive physiology of the Mediterranean flour larvae, Anagasta kuehniella.

    Science.gov (United States)

    de Oliveira, Caio Fernando Ramalho; de Moura, Maiara Celine; Napoleão, Thiago Henrique; Paiva, Patrícia Maria Guedes; Coelho, Luana Cassandra Breitenbach Barroso; Macedo, Maria Lígia Rodrigues

    2017-10-01

    Biotechnological techniques allow the investigation of alternatives to outdated chemical insecticides for crop protection; some investigations have focused on the identification of molecules tailored from nature for this purpose. We, herein, describe the negative effects of water-soluble lectin from Moringa oleifera seeds (WSMoL) on Anagasta kuehniella development. The chitin-binding lectin, WSMoL, impaired the larval weight gain by 50% and affected the activity of the pest's major digestive enzymes. The commitment of the digestive process became evident after controlled digestion studies, where the capacity of protein digestion was compromised by >90%. Upon acute exposure, the lectin was not resistant to digestion; however, chronic ingestion of WSMoL was able to reverse this feature. Thus, we show that resistance to digestion may not be a prerequisite for a lectin's ability to exert negative effects on larval physiology. The mechanism of action of WSMoL involves binding to chitin with possible disruption to the peritrophic membrane, causing disorder between the endo- and ectoperitrophic spaces. Additionally, results suggest that WSMoL may trigger apoptosis in gut cells, leading to the lower enzymatic activity observed in WSMoL-fed larvae. Although assays employing an artificial diet did not demonstrate effects of WSMoL on A. kuehniella mortality, this lectin may hold potential for exerting insecticide effects on other pest insects, as well for use in other experimental approaches, such as WSMoL-expressing plants. Moreover, the use of WSMoL with other biotechnological tools, such as 'pyramid' crops, may represent a strategy for delaying the evolution of pest resistance to transgenic crops, since its multiple site targets could act in synergism with other insecticide compounds. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Plant Lectins as Medical Tools against Digestive System Cancers.

    Science.gov (United States)

    Estrada-Martínez, Laura Elena; Moreno-Celis, Ulisses; Cervantes-Jiménez, Ricardo; Ferriz-Martínez, Roberto Augusto; Blanco-Labra, Alejandro; García-Gasca, Teresa

    2017-07-03

    Digestive system cancers-those of the esophagus, stomach, small intestine, colon-rectum, liver, and pancreas-are highly related to genetics and lifestyle. Most are considered highly mortal due to the frequency of late diagnosis, usually in advanced stages, caused by the absence of symptoms or masked by other pathologies. Different tools are being investigated in the search of a more precise diagnosis and treatment. Plant lectins have been studied because of their ability to recognize and bind to carbohydrates, exerting a variety of biological activities on animal cells, including anticancer activities. The present report integrates existing information on the activity of plant lectins on various types of digestive system cancers, and surveys the current state of research into their properties for diagnosis and selective treatment.

  15. Plant Lectins as Medical Tools against Digestive System Cancers

    Directory of Open Access Journals (Sweden)

    Laura Elena Estrada-Martínez

    2017-07-01

    Full Text Available Digestive system cancers—those of the esophagus, stomach, small intestine, colon-rectum, liver, and pancreas—are highly related to genetics and lifestyle. Most are considered highly mortal due to the frequency of late diagnosis, usually in advanced stages, caused by the absence of symptoms or masked by other pathologies. Different tools are being investigated in the search of a more precise diagnosis and treatment. Plant lectins have been studied because of their ability to recognize and bind to carbohydrates, exerting a variety of biological activities on animal cells, including anticancer activities. The present report integrates existing information on the activity of plant lectins on various types of digestive system cancers, and surveys the current state of research into their properties for diagnosis and selective treatment.

  16. Multivalent Carbohydrate-Lectin Interactions: How Synthetic Chemistry Enables Insights into Nanometric Recognition

    Directory of Open Access Journals (Sweden)

    René Roy

    2016-05-01

    Full Text Available Glycan recognition by sugar receptors (lectins is intimately involved in many aspects of cell physiology. However, the factors explaining the exquisite selectivity of their functional pairing are not yet fully understood. Studies toward this aim will also help appraise the potential for lectin-directed drug design. With the network of adhesion/growth-regulatory galectins as therapeutic targets, the strategy to recruit synthetic chemistry to systematically elucidate structure-activity relationships is outlined, from monovalent compounds to glyco-clusters and glycodendrimers to biomimetic surfaces. The versatility of the synthetic procedures enables to take examining structural and spatial parameters, alone and in combination, to its limits, for example with the aim to produce inhibitors for distinct galectin(s that exhibit minimal reactivity to other members of this group. Shaping spatial architectures similar to glycoconjugate aggregates, microdomains or vesicles provides attractive tools to disclose the often still hidden significance of nanometric aspects of the different modes of lectin design (sequence divergence at the lectin site, differences of spatial type of lectin-site presentation. Of note, testing the effectors alone or in combination simulating (pathophysiological conditions, is sure to bring about new insights into the cooperation between lectins and the regulation of their activity.

  17. Glycan microarray analysis of the carbohydrate-recognition specificity of native and recombinant forms of the lectin ArtinM

    Directory of Open Access Journals (Sweden)

    Y. Liu

    2015-12-01

    Full Text Available This article contains data related to the researc.h article entitled “Yeast-derived ArtinM shares structure, carbohydrate recognition, and biological effects with native ArtinM” by Cecílio et al. (2015 [1]. ArtinM, a D-mannose-binding lectin isolated from the seeds of Artocarpus heterophyllus, exerts immunomodulatory and regenerative activities through its Carbohydrate Recognition Domain (CRD (Souza et al., 2013; Mariano et al., 2014 [2,3]. The limited availability of the native lectin (n-ArtinM led us to characterize a recombinant form of the protein, obtained by expression in Saccharomyces cerevisiae (y-ArtinM. We compared the carbohydrate-binding specificities of y-ArtinM and n-ArtinM by analyzing the binding of biotinylated preparations of the two lectin forms using a neoglycolipid (NGL-based glycan microarray. Data showed that y-ArtinM mirrored the specificity exhibited by n-ArtinM.

  18. Griffithsin: An Antiviral Lectin with Outstanding Therapeutic Potential

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    Sabrina Lusvarghi

    2016-10-01

    Full Text Available Griffithsin (GRFT, an algae-derived lectin, is one of the most potent viral entry inhibitors discovered to date. It is currently being developed as a microbicide with broad-spectrum activity against several enveloped viruses. GRFT can inhibit human immunodeficiency virus (HIV infection at picomolar concentrations, surpassing the ability of most anti-HIV agents. The potential to inhibit other viruses as well as parasites has also been demonstrated. Griffithsin’s antiviral activity stems from its ability to bind terminal mannoses present in high-mannose oligosaccharides and crosslink these glycans on the surface of the viral envelope glycoproteins. Here, we review structural and biochemical studies that established mode of action and facilitated construction of GRFT analogs, mechanisms that may lead to resistance, and in vitro and pre-clinical results that support the therapeutic potential of this lectin.

  19. Differential Lectin Binding Patterns Identify Distinct Heart Regions in Giant Danio (Devario aequipinnatus) and Zebrafish (Danio rerio) Hearts

    Science.gov (United States)

    Manalo, Trina; May, Adam; Quinn, Joshua; Lafontant, Dominique S.; Shifatu, Olubusola; He, Wei; Gonzalez-Rosa, Juan M.; Burns, Geoffrey C.; Burns, Caroline E.; Burns, Alan R.; Lafontant, Pascal J.

    2016-01-01

    Lectins are carbohydrate-binding proteins commonly used as biochemical and histochemical tools to study glycoconjugate (glycoproteins, glycolipids) expression patterns in cells, tissues, including mammalian hearts. However, lectins have received little attention in zebrafish (Danio rerio) and giant danio (Devario aequipinnatus) heart studies. Here, we sought to determine the binding patterns of six commonly used lectins—wheat germ agglutinin (WGA), Ulex europaeus agglutinin, Bandeiraea simplicifolia lectin (BS lectin), concanavalin A (Con A), Ricinus communis agglutinin I (RCA I), and Lycopersicon esculentum agglutinin (tomato lectin)—in these hearts. Con A showed broad staining in the myocardium. WGA stained cardiac myocyte borders, with binding markedly stronger in the compact heart and bulbus. BS lectin, which stained giant danio coronaries, was used to measure vascular reconstruction during regeneration. However, BS lectin reacted poorly in zebrafish. RCA I stained the compact heart of both fish. Tomato lectin stained the giant danio, and while low reactivity was seen in the zebrafish ventricle, staining was observed in their transitional cardiac myocytes. In addition, we observed unique staining patterns in the developing zebrafish heart. Lectins’ ability to reveal differential glycoconjugate expression in giant danio and zebrafish hearts suggests they can serve as simple but important tools in studies of developing, adult, and regenerating fish hearts. PMID:27680670

  20. A novel core 1 O-linked glycan-specific binding lectin from the fruiting body of Hericium erinaceus.

    Science.gov (United States)

    Kim, Seonghun

    2018-02-01

    Mucin-type O-glycans are involved in biological functions on the cell surface as well as the glycoproteins and can also be used as specific carbohydrate biomarkers of many diseases. In this study, I purified a novel core 1 O-linked glycan specific lectin, Hericium erinaceus lecin (HeL), from the fruiting body of the mushroom Hericium erinaceus, which is known as the natural source for a sialic acid-binding lectin. Upon optimization of the purification conditions, a sequence of ion exchange, affinity, ion exchange, and size-exclusion chromatography resulted in the highest yield and best quality of lectin without protease activity. The resulting purified HeL is an apparent hexameric protein with a subunit molecular weight of 15kDa, and a pI of 4.3. In hemagglutination inhibition assay, the purified lectin was only inhibited by glycoproteins containing mucin-type O-glycans and reacted weakly with Galβ(1,3)GalNAc. Glycan array analyses showed that HeL specifically interacts with core 1 O-linked glycans as well as extended O-glycan structures containing sialylation or fucosylation. The glycan binding specificity of HeL is comparable to that of peanut agglutinin for detection of a broader range of extended core 1 O-glycan structures. Taken together, these results provide an efficient and optimized procedure for the purification of HeL from the fruiting body of the mushroom Hericium erinaceus. Moreover, HeL represents a powerful tool for analyzing core 1 and extended core 1 O- glycan structures in diagnosis assays. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Purification, physicochemical characterization, saccharide specificity, and chemical modification of a Gal/GalNAc specific lectin from the seeds of Trichosanthes dioica.

    Science.gov (United States)

    Sultan, Nabil Ali Mohammed; Kenoth, Roopa; Swamy, Musti J

    2004-12-15

    A new galactose-specific lectin has been purified from the extracts of Trichosanthes dioica seeds by affinity chromatography on cross-linked guar gum. The purified lectin (T. dioica seed lectin, TDSL) moved as a single symmetrical peak on gel filtration on Superose-12 in the presence of 0.1 M lactose with an M(r) of 55 kDa. In the absence of ligand, the movement was retarded, indicating a possible interaction of the lectin with the column matrix. In SDS-PAGE, in the presence of beta-mercaptoethanol, two non-identical bands of M(r) 24 and 37 kDa were observed, whereas in the absence of beta-mercaptoethanol, the lectin yielded a single band corresponding to approximately 55,000 Da, indicating that the two subunits of TDSL are connected by one or more disulfide bridges. TDSL is a glycoprotein with about 4.9% covalently bound neutral sugar. Analysis of near-UV CD spectrum by three different methods (CDSSTR, CONTINLL, and SELCON3) shows that TDSL contains 13.3% alpha-helix, 36.7% beta-sheet, 19.4% beta-turns, and 31.6% unordered structure. Among a battery of sugars investigated, TDSL was inhibited strongly by beta-d-galactopyranosides, with 4-methylumbelliferyl-beta-d-galactopyranoside being the best ligand. Chemical modification studies indicate that tyrosine residues are important for the carbohydrate-binding and hemagglutinating activities of the lectin. A partial protection was observed when the tyrosine modification was performed in the presence of 0.2 M lactose. The tryptophan residues of TDSL appear to be buried in the protein interior as they could not be modified under native conditions, whereas upon denaturation with 8 M urea two Trp residues could be selectively modified by N-bromosuccinimide. The subunit composition and size, secondary structure, and sugar specificity of this lectin are similar to those of type-2 ribosome inactivating proteins, suggesting that TDSL may belong to this protein family.

  2. Factor analysis shows association between family activity environment and children's health behaviour.

    Science.gov (United States)

    Hendrie, Gilly A; Coveney, John; Cox, David N

    2011-12-01

    To characterise the family activity environment in a questionnaire format, assess the questionnaire's reliability and describe its predictive ability by examining the relationships between the family activity environment and children's health behaviours - physical activity, screen time and fruit and vegetable intake. This paper describes the creation of a tool, based on previously validated scales, adapted from the food domain. Data are from 106 children and their parents (Adelaide, South Australia). Factor analysis was used to characterise factors within the family activity environment. Pearson-Product Moment correlations between the family environment and child outcomes, controlling for demographic variation, were examined. Three factors described the family activity environment - parental activity involvement, opportunity for role modelling and parental support for physical activity - and explained 37.6% of the variance. Controlling for demographic factors, the scale was significantly correlated with children's health behaviour - physical activity (r=0.27), screen time (r=-0.24) and fruit and vegetable intake (r=0.34). The family activity environment questionnaire shows high internal consistency and moderate predictive ability. This study has built on previous research by taking a more comprehensive approach to measuring the family activity environment. This research suggests the family activity environment should be considered in family-based health promotion interventions. © 2011 The Authors. ANZJPH © 2011 Public Health Association of Australia.

  3. Recent Progress in Lectin-Based Biosensors

    Directory of Open Access Journals (Sweden)

    Baozhen Wang

    2015-12-01

    Full Text Available This article reviews recent progress in the development of lectin-based biosensors used for the determination of glucose, pathogenic bacteria and toxins, cancer cells, and lectins. Lectin proteins have been widely used for the construction of optical and electrochemical biosensors by exploiting the specific binding affinity to carbohydrates. Among lectin proteins, concanavalin A (Con A is most frequently used for this purpose as glucose- and mannose-selective lectin. Con A is useful for immobilizing enzymes including glucose oxidase (GOx and horseradish peroxidase (HRP on the surface of a solid support to construct glucose and hydrogen peroxide sensors, because these enzymes are covered with intrinsic hydrocarbon chains. Con A-modified electrodes can be used as biosensors sensitive to glucose, cancer cells, and pathogenic bacteria covered with hydrocarbon chains. The target substrates are selectively adsorbed to the surface of Con A-modified electrodes through strong affinity of Con A to hydrocarbon chains. A recent topic in the development of lectin-based biosensors is a successful use of nanomaterials, such as metal nanoparticles and carbon nanotubes, for amplifying output signals of the sensors. In addition, lectin-based biosensors are useful for studying glycan expression on living cells.

  4. Glyceraldehyde-3-phosphate dehydrogenase from Chironomidae showed differential activity towards metals.

    Science.gov (United States)

    Chong, Isaac K W; Ho, Wing S

    2013-09-01

    Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is known to interact with different biomolecules and was implicated in many novel cellular activities including programmed cell death, nuclear RNA transport unrelated to the commonly known carbohydrate metabolism. We reported here the purification of GAPDH from Chironomidae larvae (Insecta, Diptera) that showed different biologic activity towards heavy metals. It was inhibited by copper, cobalt nickel, iron and lead but was activated by zinc. The GAPDH was purified by ammonium sulphate fractionation and Chelating Sepharose CL-6B chromatography followed by Blue Sepharose CL-6B chromatography. The 150-kDa tetrameric GAPDH showed optimal activity at pH 8.5 and 37°C. The multiple alignment of sequence of the Chironomidae GAPDH with other known species showed 78 - 88% identity to the conserved regions of the GADPH. Bioinformatic analysis unveils substantial N-terminal sequence similarity of GAPDH of Chironomidae larvae to mammalian GADPHs. However, the GADPH of Chironomidae larvae showed different biologic activities and cytotoxicity towards heavy metals. The GAPDH enzyme would undergo adaptive molecular changes through binding at the active site leading to higher tolerance to heavy metals.

  5. Rachycentron canadum (cobia) lectin promoted mitogenic response in mice BALB/c splenocytes.

    Science.gov (United States)

    Coriolano, M C; de Melo, C M L; Santos, A J G; Pereira, V R A; Coelho, L C B B

    2012-12-01

    The mitogenic lectins are invaluable tools to study the biochemical changes associated with lymphocyte activation and proliferation of various immune cells. Rachycentron canadum lectin (RcaL) was detected and purified from serum of cobia fish. The aim of this study was to evaluate the proliferative response and cytokine production in splenocytes of mice in vitro stimulated with RcaL lectin; Canavalia ensiformis lectin (Con A) was used as positive control. A high proliferation index was induced by RcaL in relation to control cells. Furthermore, RcaL induced higher IL-2 and IL-6 production in relation to control. The cell viability was 90% in splenocytes treated with RcaL lectin, but RcaL promoted significant late apoptosis after 24 and 48 h in relation to control. RcaL induced proliferative responses suggesting that this lectin can be used as a mitogenic agent in immunostimulatory assays. © 2012 The Authors. Scandinavian Journal of Immunology © 2012 Blackwell Publishing Ltd.

  6. Dietary Plant Lectins Appear to Be Transported from the Gut to Gain Access to and Alter Dopaminergic Neurons of Caenorhabditis elegans, a Potential Etiology of Parkinson’s Disease

    Science.gov (United States)

    Zheng, Jolene; Wang, Mingming; Wei, Wenqian; Keller, Jeffrey N.; Adhikari, Binita; King, Jason F.; King, Michael L.; Peng, Nan; Laine, Roger A.

    2016-01-01

    Lectins from dietary plants have been shown to enhance drug absorption in the gastrointestinal tract of rats, be transported trans-synaptically as shown by tracing of axonal and dendritic paths, and enhance gene delivery. Other carbohydrate-binding protein toxins are known to traverse the gut intact in dogs. Post-feeding rhodamine- or TRITC-tagged dietary lectins, the lectins were tracked from gut to dopaminergic neurons (DAergic-N) in transgenic Caenorhabditis elegans (C. elegans) [egIs1(Pdat-1:GFP)] where the mutant has the green fluorescent protein (GFP) gene fused to a dopamine transport protein gene labeling DAergic-N. The lectins were supplemented along with the food organism Escherichia coli (OP50). Among nine tested rhodamine/TRITC-tagged lectins, four, including Phaseolus vulgaris erythroagglutinin (PHA-E), Bandeiraea simplicifolia (BS-I), Dolichos biflorus agglutinin (DBA), and Arachis hypogaea agglutinin (PNA), appeared to be transported from gut to the GFP-DAergic-N. Griffonia Simplicifolia and PHA-E, reduced the number of GFP-DAergic-N, suggesting a toxic activity. PHA-E, BS-I, Pisum sativum (PSA), and Triticum vulgaris agglutinin (Succinylated) reduced fluorescent intensity of GFP-DAergic-N. PHA-E, PSA, Concanavalin A, and Triticum vulgaris agglutinin decreased the size of GFP-DAergic-N, while BS-I increased neuron size. These observations suggest that dietary plant lectins are transported to and affect DAergic-N in C. elegans, which support Braak and Hawkes’ hypothesis, suggesting one alternate potential dietary etiology of Parkinson’s disease (PD). A recent Danish study showed that vagotomy resulted in 40% lower incidence of PD over 20 years. Differences in inherited sugar structures of gut and neuronal cell surfaces may make some individuals more susceptible in this conceptual disease etiology model. PMID:27014695

  7. Dietary plant lectins appear to be transported from the gut to gain access to and alter dopaminergic neurons of Caenorhabditis elegans, a potential etiology of Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Jolene eZheng

    2016-03-01

    Full Text Available Lectins from dietary plants have been shown to enhance drug absorption in the gastrointestinal tract of rats, be transported trans-synaptically as shown by tracing of axonal and dendritic paths, and enhance gene delivery. Other carbohydrate-binding protein toxins are known to traverse the gut intact in dogs. Post-feeding rhodamine- or TRITC-tagged dietary lectins, the lectins were tracked from gut to dopaminergic neurons (DAergic-N in transgenic Caenorhabditis elegans (C. elegans (egIs1[Pdat-1::GFP] where the mutant has the Green Fluorescent Protein (GFP gene fused to a dopamine transport protein gene labeling dopaminergic neurons, The lectins were supplemented along with the food organism Escherichia coli (OP50. Among nine tested rhodamine/TRITC-tagged lectins, four, including Phaseolus vulgaris erythroagglutinin (PHA-E, Bandeiraea simplicifolia (BS-I, Dolichos biflorus agglutinin (DBA, and Arachis hypogaea (PNA, appeared to be transported from gut to the GFP-DAergic-N. Griffonia Simplicifolia (GSL-I and PHA-E, reduced the number of GFP-DAergic-N suggesting a toxic activity. PHA-E, BS-I, Pisum Sativum (PSA, and Triticum vulgaris agglutinin (Succinylated reduced fluorescent intensity of GFP-DAergic-N. PHA-E, PSA, Concanavalin A, and Triticum vulgaris agglutinin decreased the size of GFP-DAergic-N, while BS-I increased neuron size. These observations suggest that dietary plant lectins are transported to and affect DAergic-N in C. elegans, which support Braak and Hawkes’ hypothesis, suggesting one alternate potential dietary etiology of Parkinson’s disease (PD. A recent Danish study showed that vagotomy resulted in 40% lower incidence of PD over 20 years. Differences in inherited sugar structures of gut and neuronal cell surfaces may make some individuals more susceptible in this conceptual disease etiology model.

  8. A humanized anti-M2 scFv shows protective in vitro activity against influenza

    Energy Technology Data Exchange (ETDEWEB)

    Bradbury, Andrew M [Los Alamos National Laboratory; Velappan, Nileena [Los Alamos National Laboratory; Schmidt, Jurgen G [Los Alamos National Laboratory

    2008-01-01

    M2 is one of the most conserved influenza proteins, and has been widely prospected as a potential universal vaccine target, with protection predominantly mediated by antibodies. In this paper we describe the creation of a humanized single chain Fv from 14C2, a potent monoclonal antibody against M2. We show that the humanized scFv demonstrates similar activity to the parental mAb: it is able to recognize M2 in its native context on cell surfaces and is able to show protective in vitro activity against influenza, and so represents a potential lead antibody candidate for universal prophylactic or therapeutic intervention in influenza.

  9. Immunocytochemical localisation of phloem lectin from Cucurbita maxima using peroxidase and colloidal-gold labels.

    Science.gov (United States)

    Smith, L M; Sabnis, D D; Johnson, R P

    1987-04-01

    Antibodies were raised against lectin purified from the sieve-tube exudate of Cucurbita maxima. Immunocytochemistry, using peroxidase-labelled antibodies and Protein A-colloidal gold, was employed to determine the location of the lectin within the tissues and cells of C. maxima and other cucurbit species. The anti-lectin antibodies bound to P-protein aggregates in sieve elements and companion cells, predominantly in the extrafascicular phloem of C. maxima. This may reflect the low rate of translocation in these cells. Under the electron microscope, the lectin was shown to be a component of P-protein filaments and was also found in association with the sieve-tube reticulum which lines the plasmalemma. The anti-lectin antibodies reacted with sieve-tube proteins from other species of the genus Cucurbita but showed only limited reaction with other genera. We suggest that the lectin serves to anchor P-protein filaments and associated proteins to the parietal layer of sieve elements.

  10. Incident microalbuminuria and complement factor mannan-binding lectin-associated protein 19 in people with newly diagnosed type 1 diabetes

    DEFF Research Database (Denmark)

    Ostergaard, J A; Thiel, S; Hoffmann-Petersen, I T

    2017-01-01

    BACKGROUND: Evidence links the lectin pathway of complement activation to diabetic kidney disease. Upon carbohydrate-recognition by pattern-recognition molecules, e.g., mannan-binding lectin (MBL), the MBL-associated serine protease (MASP-2) is activated and initiates the complement cascade. The ...

  11. Technical Report on the Development of Novel Technology for Reducing the Toxicity of Mistletoe Lectin by using Radiation Fusion Technology

    International Nuclear Information System (INIS)

    Lee, Ju Woon; Kim, Jae Hun; Choi, Jong Il; Song, Beom Seok; Yoon, Yo Han; Jung, Pil Mun; Sung, Nak Yun

    2009-10-01

    The aim of this study was conducted to investigate the effect of irradiation on detoxification, structural change, and physiological change of Mistletoe lectin. Optimal irradiation dose was determined from the result of having maximum detoxification and remaining the immunological activity Irradiation technology could be effective method for detoxification of Mistletoe lectin containing the immunological activity. The results indicate the feasibility of novel technology for reduction of the toxicity of Mistletoe lectin by using radiation technology. Practical state though clinical test is needed to extend biomedicine field using radiation technology and improve of public health by the control of the disease that gradually increase every year

  12. Acid phosphatase from stored Poa pratensis caryopses and its ability for binding to lectins

    Directory of Open Access Journals (Sweden)

    Irena Lorenc-Kubis

    2014-01-01

    Full Text Available The effect of the storage period of Poa pratensis caryopses on acid phosphatase activity and on the ability of this enzyme to interact with lectins has been studied. It has been shown that after ten years of caryopses storage, the activity of acid phosphatase decreased about 50 per cent, while the content of proteins and carbohydrates did not change. The decrease of enzyme activity during the long period of storage was found only in seeds, but not in chaffs. Acid phosphatase was isolated from caryopses stored one, two, three, five and ten years. The enzyme showed the ability to bind to immoblized as well as to free conA during the whole period of storage, hut did not react with Wheat Germen Agglutinin (WGA. The activation of acid phosphatase by binding to conA decreased with the length of storage period.

  13. [Studies on the location of eight lectins in breast carcinoma].

    Science.gov (United States)

    Zheng, Z; Ji, Z M

    1990-12-01

    100 cases of breast carcinoma were studied with lectin affinitive histochemistry technology. The result showed that Ricinus comunis agglutinin (RCA1) was located in almost all intraductal carcinomas but one, while the positive rates in the other types were obviously low (P less than 0.05). The positive rate of Ulex europaeus agglutinin-I (UEA1) in well-differentiated types was higher than that in poorly-differentiated ones (P less than 0.05). The location of Peanut agglutinin (PNA), Bandeiraea Simplicifolia (BSL) and UEA1 in breast carcinomas exhibited some regularity and it might be useful in understanding the differentiation of breast carcinomas. No relationship between changes of the eight lectins and metastases in axillary lymph nodes was observed, but the authors considered that PNA-affinitive histochemistry was beneficial to the detection of micrometastases in lymph nodes.

  14. Tolerability assessment of a lectin fraction from Tepary bean seeds (Phaseolus acutifolius orally administered to rats

    Directory of Open Access Journals (Sweden)

    Roberto Ferriz-Martínez

    2015-01-01

    Full Text Available Our previous studies have shown that a lectin rich fraction (TBLF extracted from Tepary bean seeds differentially inhibits cancer cells proliferation in vitro. Before testing the in vivo anticancer effect, the acute and subchronic toxicological assays in rats were conducted, where an oral dose of 50 mg/body weight kg was determined as the NOAEL. This study evaluated the resistance to digestion and complete blood count (CBC after 24 h of the orally administered 50 mg/kg TBLF. The digestion resistance test showed lectins activity retention after 72 h and the CBC study showed a high level of eosinophils, suggesting an allergic-like response. Tolerability was assayed after 6 weeks of treatment by dosing with an intragastric cannula every third day per week. It was observed a transient reduction in food intake and body weight in the first weeks, resulting in body weight gain reduction of 10% respect to the control group at the end of the study. Additionally, organs weight, histopathological analysis and blood markers for nutritional status and for liver, pancreas and renal function were not affected. Our results suggest that 50 mg/kg TBLF administered by oral route, exhibit no toxicity in rats and it was well tolerated. Further studies will focus on long-term studies.

  15. Physically Active Men Show Better Semen Parameters than Their Sedentary Counterparts.

    Science.gov (United States)

    Lalinde-Acevedo, Paula C; Mayorga-Torres, B Jose Manuel; Agarwal, Ashok; du Plessis, Stefan S; Ahmad, Gulfam; Cadavid, Ángela P; Cardona Maya, Walter D

    2017-10-01

    The quality of semen depends upon several factors such as environment, life style, physical activity, age, and occupation. The aim of this study was to analyze and compare the conventional and functional semen parameters in men practicing vigorous physical activity to those of sedentary men. In this descriptive cross-sectional study, semen samples of 17 physically active men and 15 sedentary men were collected for analysis. Semen analysis was performed according to the World Health Organization (WHO) guidelines, while functional parameters were evaluated by flow cytometry. Results showed that several semen parameters (semen volume, viability, progressive motility, total motility, normal morphology, and moribund cells) were superior in the physically active group in comparison with the sedentary group. Semen parameters such as viability, progressive motility and total motility, as well as the percentage of moribund spermatozoa were significantly different between both groups. However, sperm DNA damage, lipid peroxidation and mitochondrial potential were not significantly different among the groups. Nevertheless, the physical activity shows better semen parameters than sedentary group. Taken together, our results demonstrate that regular physical activity has beneficial impact in sperm fertility parameters and such a life style can enhance the fertility status of men. Copyright© by Royan Institute. All rights reserved.

  16. Lectin binding patterns and immunohistochemical antigen detection ...

    African Journals Online (AJOL)

    Ibrahim Eldaghayes

    2018-02-09

    Feb 9, 2018 ... placenta and lungs of Brucella abortus-bovine infected fetuses. María Andrea ... The present lectin histochemical study revealed a distinctive pattern of oligosaccharide .... tissue was used as a positive control and nonimmune.

  17. Lectin receptors in the human cornea.

    Science.gov (United States)

    Holmes, M J; Mannis, M J; Lund, J; Jacobs, L

    Five different biotin labeled lectins, Concanavalin-A (Con A), wheat germ agglutinin (WGA), Ricinus communis agglutinin I (RCA1), Ulex europaeus agglutinin (UEA1), and soybean agglutinin (SBA) were used to study lectin receptors on formalin-fixed paraffin embedded human corneas. Con A stained the cytoplasm, cell, and nuclear membranes of the epithelial cells and stained the stroma diffusely. WGA stained the superficial epithelial cells, the epithelial cell membranes, and the keratocytes of the stroma. SBA did not react with any of the corneal layers. RCA1 heavily stained the keratocytes but did not stain the epithelium. UEA1 lightly stained the epithelial cell cytoplasm and interstitial stroma. All staining reactions could be abolished by omission of the lectin or by the use of the appropriate inhibitory sugar. The lectin binding patterns reported here provide a means for further investigation of carbohydrate structures in the human cornea in both normal and disease states.

  18. A C-type lectin from Bothrops jararacussu venom can adhere to extracellular matrix proteins and induce the rolling of leukocytes

    Directory of Open Access Journals (Sweden)

    S. L. Elífio-Esposito

    2007-01-01

    Full Text Available Purification of a lectin from Bothrops jararacussu venom (BjcuL was carried out using agarose-D-galactose affinity gel. MALDI-TOF gave a major signal at m/z 32028, suggesting the presence of a dimmer composed of two identical subunits. Divalent cations were required for the lectin activity, as complete absence of such ions reduced hemagglutination. BjcuL was more effective at neutral pH and showed total loss of activity at pH values below 4.0 and above 9.0. Its agglutinating activity remained stable at 25°C until 60min, but increased when at 35°C for at least 15min. Adhesion assays to extracellular matrix (ECM glycoproteins showed that the biotinylated lectin (0.039-5.0µg/100µl was capable of binding to fibronectin and vitronectin in a dose-dependent manner. The binding was partially inhibited in the presence of D-galactose. BjcuL (1.25-10µg/30µl potential was investigated for leukocyte rolling and adhesion to endothelial cells in living microvessels using intravital microscopy, which showed that it induced a dose-dependent increase in rolling and adherence of leukocytes, acting directly on endothelial cells of postcapillary venules. The specific association between lectins and their ligands, either on the cell surface or on the ECM, is related to a variety of biological processes. The complementary characterization of BjcuL, shown here, is useful to further understand the venom effects and as a background for future investigation for therapeutic strategies.

  19. Psychoacoustic Tinnitus Loudness and Tinnitus-Related Distress Show Different Associations with Oscillatory Brain Activity

    Science.gov (United States)

    Balkenhol, Tobias; Wallhäusser-Franke, Elisabeth; Delb, Wolfgang

    2013-01-01

    Background The phantom auditory perception of subjective tinnitus is associated with aberrant brain activity as evidenced by magneto- and electroencephalographic studies. We tested the hypotheses (1) that psychoacoustically measured tinnitus loudness is related to gamma oscillatory band power, and (2) that tinnitus loudness and tinnitus-related distress are related to distinct brain activity patterns as suggested by the distinction between loudness and distress experienced by tinnitus patients. Furthermore, we explored (3) how hearing impairment, minimum masking level, and (4) psychological comorbidities are related to spontaneous oscillatory brain activity in tinnitus patients. Methods and Findings Resting state oscillatory brain activity recorded electroencephalographically from 46 male tinnitus patients showed a positive correlation between gamma band oscillations and psychoacoustic tinnitus loudness determined with the reconstructed tinnitus sound, but not with the other psychoacoustic loudness measures that were used. Tinnitus-related distress did also correlate with delta band activity, but at electrode positions different from those associated with tinnitus loudness. Furthermore, highly distressed tinnitus patients exhibited a higher level of theta band activity. Moreover, mean hearing loss between 0.125 kHz and 16 kHz was associated with a decrease in gamma activity, whereas minimum masking levels correlated positively with delta band power. In contrast, psychological comorbidities did not express significant correlations with oscillatory brain activity. Conclusion Different clinically relevant tinnitus characteristics show distinctive associations with spontaneous brain oscillatory power. Results support hypothesis (1), but exclusively for the tinnitus loudness derived from matching to the reconstructed tinnitus sound. This suggests to preferably use the reconstructed tinnitus spectrum to determine psychoacoustic tinnitus loudness. Results also support

  20. Lectin binders. A new group of plant proteins

    Energy Technology Data Exchange (ETDEWEB)

    Rudiger, H; Gebauer, G; Gansera, R; Schurz, H; Schimpl, A [Wuerzburg Univ. (Germany, F.R.)

    1982-09-01

    Lectins are widely distributed in the plant kingdom, many of them being well characterized in their chemical structure and the effects they have on alien biological systems such as erythrocytes or lymphocytes. The biological function of plant lectins remains speculative. We therefore inspected plant extracts from components which might bind specifically to the lectin from the respective plant. Single proteins (lectin binders) could be isolated from each plant extract. The interaction of these proteins with lectins was demonstrated and qualified by several methods. Similar to the lectins, the lectin binders are localized in the cytoplasm in contrast to them, however, they persist during germination and plant growth. Their precise role in the plant is not known, but they are likely to be associated with lectins not only in vitro but also in vivo. They also interact with alien cells, and are able to stimulate mitosis in murine lymphocytes. Some lectin binders act specifically on B lymphocytes, leaving T cells uninfluenced.

  1. Lectin interactions with alpha-galactosylated xenoantigens

    DEFF Research Database (Denmark)

    Kirkeby, Svend; Moe, Dennis

    2002-01-01

    alpha-Galactosylated xenoantigens (Galalpha1-3Galbeta1-4GlcNAcbeta1 and Galalpha1-3Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc) are often detected with the alpha-Gal specific lectin Griffonia simplicifolia 1 isolectin B4 (GS1 B4). However, this lectin exhibits a broad and variable specificity for carboh...

  2. Mannose-binding lectin and Ficolin-2 gene polymorphisms predispose to cytomegalovirus (re)infection after orthotopic liver transplantation

    NARCIS (Netherlands)

    de Rooij, Bert-Jan F.; van der Beek, Martha T.; van Hoek, Bart; Vossen, Ann C. T. M.; ten Hove, W. Rogier; Roos, Anja; Schaapherder, Alexander F.; Porte, Robert J.; van der Reijden, Johan J.; Coenraad, Minneke J.; Hommes, Daniel W.; Verspaget, Hein W.

    2011-01-01

    Background & Aims: The lectin pathway of complement activation is a crucial effector cascade of the innate immune response to pathogens. Cytomegalovirus (CMV) infection occurs frequently in immunocompromised patients after orthotopic liver transplantation (OLT). Single-nucleotide polymorphisms

  3. CancerLectinDB: a database of lectins relevant to cancer.

    Science.gov (United States)

    Damodaran, Deepa; Jeyakani, Justin; Chauhan, Alok; Kumar, Nirmal; Chandra, Nagasuma R; Surolia, Avadhesha

    2008-04-01

    The role of lectins in mediating cancer metastasis, apoptosis as well as various other signaling events has been well established in the past few years. Data on various aspects of the role of lectins in cancer is being accumulated at a rapid pace. The data on lectins available in the literature is so diverse, that it becomes difficult and time-consuming, if not impossible to comprehend the advances in various areas and obtain the maximum benefit. Not only do the lectins vary significantly in their individual functional roles, but they are also diverse in their sequences, structures, binding site architectures, quaternary structures, carbohydrate affinities and specificities as well as their potential applications. An organization of these seemingly independent data into a common framework is essential in order to achieve effective use of all the data towards understanding the roles of different lectins in different aspects of cancer and any resulting applications. An integrated knowledge base (CancerLectinDB) together with appropriate analytical tools has therefore been developed for lectins relevant for any aspect of cancer, by collating and integrating diverse data. This database is unique in terms of providing sequence, structural, and functional annotations for lectins from all known sources in cancer and is expected to be a useful addition to the number of glycan related resources now available to the community. The database has been implemented using MySQL on a Linux platform and web-enabled using Perl-CGI and Java tools. Data for individual lectins pertain to taxonomic, biochemical, domain architecture, molecular sequence and structural details as well as carbohydrate specificities. Extensive links have also been provided for relevant bioinformatics resources and analytical tools. Availability of diverse data integrated into a common framework is expected to be of high value for various studies on lectin cancer biology. CancerLectinDB can be accessed through

  4. The three catalases in Deinococcus radiodurans: Only two show catalase activity

    International Nuclear Information System (INIS)

    Jeong, Sun-Wook; Jung, Jong-Hyun; Kim, Min-Kyu; Seo, Ho Seong; Lim, Heon-Man; Lim, Sangyong

    2016-01-01

    Deinococcus radiodurans, which is extremely resistant to ionizing radiation and oxidative stress, is known to have three catalases (DR1998, DRA0146, and DRA0259). In this study, to investigate the role of each catalase, we constructed catalase mutants (Δdr1998, ΔdrA0146, and ΔdrA0259) of D. radiodurans. Of the three mutants, Δdr1998 exhibited the greatest decrease in hydrogen peroxide (H_2O_2) resistance and the highest increase in intracellular reactive oxygen species (ROS) levels following H_2O_2 treatments, whereas ΔdrA0146 showed no change in its H_2O_2 resistance or ROS level. Catalase activity was not attenuated in ΔdrA0146, and none of the three bands detected in an in-gel catalase activity assay disappeared in ΔdrA0146. The purified His-tagged recombinant DRA0146 did not show catalase activity. In addition, the phylogenetic analysis of the deinococcal catalases revealed that the DR1998-type catalase is common in the genus Deinococcus, but the DRA0146-type catalase was found in only 4 of 23 Deinococcus species. Taken together, these results indicate that DR1998 plays a critical role in the anti-oxidative system of D. radiodurans by detoxifying H_2O_2, but DRA0146 does not have catalase activity and is not involved in the resistance to H_2O_2 stress. - Highlights: • The dr1998 mutant strain lost 90% of its total catalase activity. • Increased ROS levels and decreased H_2O_2 resistance were observed in dr1998 mutants. • Lack of drA0146 did not affect any oxidative stress-related phenotypes. • The purified DRA0146 did not show catalase activity.

  5. The three catalases in Deinococcus radiodurans: Only two show catalase activity

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Sun-Wook [Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup, 580-185 (Korea, Republic of); Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon, 305-764 (Korea, Republic of); Jung, Jong-Hyun; Kim, Min-Kyu; Seo, Ho Seong [Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup, 580-185 (Korea, Republic of); Lim, Heon-Man [Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon, 305-764 (Korea, Republic of); Lim, Sangyong, E-mail: saylim@kaeri.re.kr [Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup, 580-185 (Korea, Republic of)

    2016-01-15

    Deinococcus radiodurans, which is extremely resistant to ionizing radiation and oxidative stress, is known to have three catalases (DR1998, DRA0146, and DRA0259). In this study, to investigate the role of each catalase, we constructed catalase mutants (Δdr1998, ΔdrA0146, and ΔdrA0259) of D. radiodurans. Of the three mutants, Δdr1998 exhibited the greatest decrease in hydrogen peroxide (H{sub 2}O{sub 2}) resistance and the highest increase in intracellular reactive oxygen species (ROS) levels following H{sub 2}O{sub 2} treatments, whereas ΔdrA0146 showed no change in its H{sub 2}O{sub 2} resistance or ROS level. Catalase activity was not attenuated in ΔdrA0146, and none of the three bands detected in an in-gel catalase activity assay disappeared in ΔdrA0146. The purified His-tagged recombinant DRA0146 did not show catalase activity. In addition, the phylogenetic analysis of the deinococcal catalases revealed that the DR1998-type catalase is common in the genus Deinococcus, but the DRA0146-type catalase was found in only 4 of 23 Deinococcus species. Taken together, these results indicate that DR1998 plays a critical role in the anti-oxidative system of D. radiodurans by detoxifying H{sub 2}O{sub 2}, but DRA0146 does not have catalase activity and is not involved in the resistance to H{sub 2}O{sub 2} stress. - Highlights: • The dr1998 mutant strain lost 90% of its total catalase activity. • Increased ROS levels and decreased H{sub 2}O{sub 2} resistance were observed in dr1998 mutants. • Lack of drA0146 did not affect any oxidative stress-related phenotypes. • The purified DRA0146 did not show catalase activity.

  6. Effects of plant lectins on in vitro fibroblast proliferation

    Directory of Open Access Journals (Sweden)

    Ana Maria Sell

    2003-06-01

    Full Text Available Lectins are carbohydrate-binding proteins that have been isolated from various sources and presented a wide spectrum of biological activities. The effects of four lectins, namely, Phaseolus vulgaris phytohemagglutinin, PHA, wheat germ agglutinin, WGA, Artocarpus integrifolia seed lectins, jacalin and artocarpin, on in vitro fibroblasts proliferation were investigated. The lectins did not influence the initial cell adhesion to the plate. PHA and WGA at 10-20 µg/mL concentrations significantly decreased fibroblasts proliferation. At these concentrations, they caused morphological alterations on cells and over 80 µg/mL, promoted cell death. Neither jacalin nor artocarpin significantly affected cell proliferation.O objetivo deste trabalho foi avaliar a influência das lectinas PHA, WGA, jacalina e artocarpina sobre a proliferação de fibroblastos in vitro. Para tanto, fibroblastos gengivais de voluntários saudáveis foram cultivados, por cinco dias, em DMEM suplementado com soro bovino fetal (10% v/v e na presença das lectinas nas concentrações finais de 0.1 a 300 µg/mL. A adesão, o crescimento e a morfologia celular foram acompanhados por microscopia de inversão e contraste de fase. O índice de proliferação foi avaliado pelo método calorimétrico usando MTT. As lectinas não alteraram a adesão inicial dos fibroblastos à placa de poliestireno. PHA e WGA, nas concentrações de 10 a 20 µg/mL, diminuíram significativamente a proliferação celular. Nestas concentrações a morfologia celular é alterada e acima de 80 µg/mL, houve100% de morte celular. As lectinas jacalina e artocarpina não influenciaram a proliferação celular.

  7. Bipolar I disorder and major depressive disorder show similar brain activation during depression.

    Science.gov (United States)

    Cerullo, Michael A; Eliassen, James C; Smith, Christopher T; Fleck, David E; Nelson, Erik B; Strawn, Jeffrey R; Lamy, Martine; DelBello, Melissa P; Adler, Caleb M; Strakowski, Stephen M

    2014-11-01

    Despite different treatments and courses of illness, depressive symptoms appear similar in major depressive disorder (MDD) and bipolar I disorder (BP-I). This similarity of depressive symptoms suggests significant overlap in brain pathways underlying neurovegetative, mood, and cognitive symptoms of depression. These shared brain regions might be expected to exhibit similar activation in individuals with MDD and BP-I during functional magnetic resonance imaging (fMRI). fMRI was used to compare regional brain activation in participants with BP-I (n = 25) and MDD (n = 25) during a depressive episode as well as 25 healthy comparison (HC) participants. During the scans, participants performed an attentional task that incorporated emotional pictures. During the viewing of emotional images, subjects with BP-I showed decreased activation in the middle occipital gyrus, lingual gyrus, and middle temporal gyrus compared to both subjects with MDD and HC participants. During attentional processing, participants with MDD had increased activation in the parahippocampus, parietal lobe, and postcentral gyrus. However, among these regions, only the postcentral gyrus also showed differences between MDD and HC participants. No differences in cortico-limbic regions were found between participants with BP-I and MDD during depression. Instead, the major differences occurred in primary and secondary visual processing regions, with decreased activation in these regions in BP-I compared to major depression. These differences were driven by abnormal decreases in activation seen in the participants with BP-I. Posterior activation changes are a common finding in studies across mood states in participants with BP-I. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Task control signals in pediatric Tourette syndrome show evidence of immature and anomalous functional activity

    Directory of Open Access Journals (Sweden)

    Jessica A Church

    2009-11-01

    Full Text Available Tourette Syndrome (TS is a pediatric movement disorder that may affect control signaling in the brain. Previous work has proposed a dual-networks architecture of control processing involving a task-maintenance network and an adaptive control network (Dosenbach et al., 2008. A prior resting-state functional connectivity MRI (rs-fcMRI analysis in TS has revealed functional immaturity in both putative control networks, with “anomalous” correlations (i.e. correlations outside the typical developmental range limited to the adaptive control network (Church et al., 2009. The present study used functional MRI (fMRI to study brain activity related to adaptive control (by studying start-cues signals, and to task-maintenance (by studying signals sustained across a task set. Two hypotheses from the previous rs-fcMRI results were tested. First, adaptive control (i.e., start-cue activity will be altered in TS, including activity inconsistent with typical development (“anomalous”. Second, group differences found in task maintenance (i.e., sustained activity will be consistent with functional immaturity in TS. We examined regions found through a direct comparison of adolescents with and without TS, as well as regions derived from a previous investigation that showed differences between unaffected children and adults. The TS group showed decreased start-cue signal magnitude in regions where start-cue activity is unchanged over typical development, consistent with anomalous adaptive control. The TS group also had higher magnitude sustained signals in frontal cortex regions that overlapped with regions showing differences over typical development, consistent with immature task maintenance in TS. The results demonstrate task-related fMRI signal differences anticipated by the atypical functional connectivity found previously in adolescents with TS, strengthening the evidence for functional immaturity and anomalous signaling in control networks in adolescents

  9. Antiparkinson drug--Mucuna pruriens shows antioxidant and metal chelating activity.

    Science.gov (United States)

    Dhanasekaran, Muralikrishnan; Tharakan, Binu; Manyam, Bala V

    2008-01-01

    Parkinson's disease is a neurodegenerative disorder for which no neurorestorative therapeutic treatment is currently available. Oxidative stress plays an important role in the pathophysiology of Parkinson's disease. The ancient Indian medical system, Ayurveda, traditionally uses Mucuna pruriens to treat Parkinson's disease. In our earlier studies, Mucuna pruriens has been shown to possess antiparkinson and neuroprotective effects in animal models of Parkinson's disease. The antioxidant activity of Mucuna pruriens was demonstrated by its ability to scavenge DPPH radicals, ABTS radicals and reactive oxygen species. Mucuna pruriens significantly inhibited the oxidation of lipids and deoxyribose sugar. Mucuna pruriens exhibited divalent iron chelating activity and did not show any genotoxic/mutagenic effect on the plasmid DNA. These results suggest that the neuroprotective and neurorestorative effect of Mucuna pruriens may be related to its antioxidant activity independent of the symptomatic effect. In addition, the drug appears to be therapeutically safe in the treatment of patients with Parkinson's disease. Copyright (c) 2007 John Wiley & Sons, Ltd.

  10. C-type Lectin Receptors for Tumor Eradication: Future Directions

    Energy Technology Data Exchange (ETDEWEB)

    Streng-Ouwehand, Ingeborg; Unger, Wendy W. J.; Kooyk, Yvette van, E-mail: y.vankooyk@vumc.nl [Department of Molecular Cell Biology and Immunology, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam (Netherlands)

    2011-08-08

    Dendritic cells are key regulators in directing immune responses and therefore are under extensive research for the induction of anti-tumor responses. DCs express a large array of receptors by which they scan their surroundings for recognition and uptake of pathogens. One of the receptor-families is the C-type lectins (CLR), which bind carbohydrate structures and internalize antigens upon recognition. Intracellular routing of antigen through CLR enhances loading and presentation of antigen through MHC class I and II, inducing antigen-specific CD4{sup +} and CD8{sup +} T-cell proliferation and skewing T-helper cells. These characteristics make CLRs very interesting targets for DC-based immunotherapy. Profound research has been done on targeting specific tumor antigens to CLR using either antibodies or the natural ligands such as glycan structures. In this review we will focus on the current data showing the potency of CLR-targeting and discuss improvements that can be achieved to enhance anti-tumor activity in the near future.

  11. The three catalases in Deinococcus radiodurans: Only two show catalase activity.

    Science.gov (United States)

    Jeong, Sun-Wook; Jung, Jong-Hyun; Kim, Min-Kyu; Seo, Ho Seong; Lim, Heon-Man; Lim, Sangyong

    2016-01-15

    Deinococcus radiodurans, which is extremely resistant to ionizing radiation and oxidative stress, is known to have three catalases (DR1998, DRA0146, and DRA0259). In this study, to investigate the role of each catalase, we constructed catalase mutants (Δdr1998, ΔdrA0146, and ΔdrA0259) of D. radiodurans. Of the three mutants, Δdr1998 exhibited the greatest decrease in hydrogen peroxide (H2O2) resistance and the highest increase in intracellular reactive oxygen species (ROS) levels following H2O2 treatments, whereas ΔdrA0146 showed no change in its H2O2 resistance or ROS level. Catalase activity was not attenuated in ΔdrA0146, and none of the three bands detected in an in-gel catalase activity assay disappeared in ΔdrA0146. The purified His-tagged recombinant DRA0146 did not show catalase activity. In addition, the phylogenetic analysis of the deinococcal catalases revealed that the DR1998-type catalase is common in the genus Deinococcus, but the DRA0146-type catalase was found in only 4 of 23 Deinococcus species. Taken together, these results indicate that DR1998 plays a critical role in the anti-oxidative system of D. radiodurans by detoxifying H2O2, but DRA0146 does not have catalase activity and is not involved in the resistance to H2O2 stress. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Winter Aconite (Eranthis hyemalis Lectin as a cytotoxic effector in the lifecycle of Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Marie-Therese McConnell

    2015-08-01

    Full Text Available The lectin found in the tubers of the Winter Aconite (Eranthis hyemalis plant is an N-acetyl-D-galactosamine specific Type II Ribosome Inactivating Protein (RIP; Type II RIPs have shown anti-cancer properties, and hence have potential as therapeutic agents. Here we present a modified protocol for the extraction and purification of the E. hyemalis lectin (EHL using affinity chromatography. De novo amino acid sequencing of EHL confirms its classification as a Type II Ribosome Inactivating Protein. The biocidal properties of EHL have been investigated against the nematode Caenorhabditis elegans. Arrested first stage larvae treated with EHL have shown some direct mortality, with surviving larvae subsequently showing a range of phenotypes including food avoidance, reduced fecundity, developmental delay and constitutive dauer larvae formation. Both inappropriate dauer larvae development and failure to locate to bacterial food source are consistent with the disruption of chemosensory function and the ablation of amphid neurons. Further investigation indicates that mutations that disrupt normal amphid formation can block the EHL-induced dauer larvae formation. In combination, these phenotypes indicate that EHL is cytotoxic and suggest a cell specific activity against the amphid neurons of C. elegans.

  13. [The significance of Ulex europaeus agglutinin I lectin binding fibers in various muscular diseases].

    Science.gov (United States)

    Yatabe, K; Hiraguri, M; Sueishi, M; Takeuchi, M; Nonaka, I; Kawai, M

    1998-05-01

    In the present study, we have reported that Ulex europaeus agglutinin I (UEA I) lectin labeled muscle fibers in distal myopathy with rimmed vacuole formation (DMRV). UEA I binding to muscle fibers was also observed in a small number of biopsies with inflammatory myopathy, but not in other diseases, including neurogenic muscular atrophies and muscular dystrophies. In order to elucidate the relationship between this UEA I binding, rimmed vacuole formation and active autophagocytosis, we examined the UEA I binding fibers in other myopathies which frequently showed rimmed vacuoles, including adult onset acid maltase deficiency, oculo-pharyngo-distal type myopathy and oculopharyngeal muscular dystrophy. No UEA I lectin labeling fiber was observed in the diseases examined. We then studied UEA I binding behavior on 70 biopsies of inflammatory myopathy to characterize the clinical features of UEA I binding positive patients. UEA I binding fibers were observed in 3 of 28 patients (11%) with other collagen diseases, 11 of 36 (31%) without these disorders, and 2 of 6 (33%) with inclusion body myositis. There were no common clinical histories, complications or laboratory findings among the UEA I binding positive patients. In conclusion, a common process may exist between the muscle fiber degeneration in DMRV and subgroups of inflammatory myopathy patients, but the basic mechanism remains to be elucidated.

  14. Subunits of the Snf1 kinase heterotrimer show interdependence for association and activity.

    Science.gov (United States)

    Elbing, Karin; Rubenstein, Eric M; McCartney, Rhonda R; Schmidt, Martin C

    2006-09-08

    The Snf1 kinase and its mammalian orthologue, the AMP-activated protein kinase (AMPK), function as heterotrimers composed of a catalytic alpha-subunit and two non-catalytic subunits, beta and gamma. The beta-subunit is thought to hold the complex together and control subcellular localization whereas the gamma-subunit plays a regulatory role by binding to and blocking the function of an auto-inhibitory domain (AID) present in the alpha-subunit. In addition, catalytic activity requires phosphorylation by a distinct upstream kinase. In yeast, any one of three Snf1-activating kinases, Sak1, Tos3, or Elm1, can fulfill this role. We have previously shown that Sak1 is the only Snf1-activating kinase that forms a stable complex with Snf1. Here we show that the formation of the Sak1.Snf1 complex requires the beta- and gamma-subunits in vivo. However, formation of the Sak1.Snf1 complex is not necessary for glucose-regulated phosphorylation of the Snf1 activation loop. Snf1 kinase purified from cells lacking the beta-subunits do not contain any gamma-subunit, indicating that the Snf1 kinase does not form a stable alphagamma dimer in vivo. In vitro kinase assays using purified full-length and truncated Snf1 proteins demonstrate that the kinase domain, which lacks the AID, is significantly more active than the full-length Snf1 protein. Addition of purified beta- and gamma-subunits could stimulate the kinase activity of the full-length alpha-subunit but only when all three subunits were present, suggesting an interdependence of all three subunits for assembly of a functional complex.

  15. Circulating mannan-binding lectin, M-, L-, H-ficolin and collectin-liver-1 levels in patients with acute liver failure

    DEFF Research Database (Denmark)

    Laursen, Tea Lund; Sandahl, Thomas D; Støy, Sidsel

    2015-01-01

    BACKGROUND & AIMS: The complement system is activated in liver diseases including acute liver failure (ALF); however, the role of the lectin pathway of complement has scarcely been investigated in ALF. The pathway is initiated by soluble pattern recognition molecules: mannan-binding lectin (MBL),...

  16. Inhibition of initial adhesion of oral bacteria through a lectin from Bauhinia variegata L. var. variegata expressed in Escherichia coli.

    Science.gov (United States)

    Klafke, G B; Borsuk, S; Gonçales, R A; Arruda, F V S; Carneiro, V A; Teixeira, E H; Coelho da Silva, A L; Cavada, B S; Dellagostin, O A; Pinto, L S

    2013-11-01

    The aim of the present work was to study the in vitro effect of native and recombinant Bauhinia variegata var. variegata lectins in inhibiting early adhesion of Streptococcus mutans, Streptococcus sanguis and Streptococcus sobrinus to experimentally acquired pellicle. Native lectin from B. variegata (BVL) was purified by affinity chromatography of extract of seeds. The recombinant lectin (rBVL-I) was expressed in E. coli strain BL21 (DE3) from a genomic clone encoding the mature B. variegata lectin gene using the vector pAE-bvlI. Recombinant protein deposited in inclusion bodies was solubilized and subsequently purified by affinity chromatography. The rBVL-I was compared to BVL for agglutination of erythrocytes and initial adherence of oral bacteria on a saliva-coated surface. The results revealed that rBVL-I acts similarly to BVL for agglutination of erythrocytes. Both lectins showed adhesion inhibition effect on Step. sanguis, Step. mutans and Step. sobrinus. We report, for the first time, the inhibition of early adhesion of oral bacteria by a recombinant lectin. Our results support the proposed biotechnological application of lectins in a strategy to reduce development of dental caries by inhibiting the initial adhesion and biofilm formation. © 2013 The Society for Applied Microbiology.

  17. Unusual sugar specificity of banana lectin from Musa paradisiaca and its probable evolutionary origin. Crystallographic and modelling studies.

    Science.gov (United States)

    Singh, D D; Saikrishnan, K; Kumar, Prashant; Surolia, A; Sekar, K; Vijayan, M

    2005-10-01

    The crystal structure of a complex of methyl-alpha-D-mannoside with banana lectin from Musa paradisiaca reveals two primary binding sites in the lectin, unlike in other lectins with beta-prism I fold which essentially consists of three Greek key motifs. It has been suggested that the fold evolved through successive gene duplication and fusion of an ancestral Greek key motif. In other lectins, all from dicots, the primary binding site exists on one of the three motifs in the three-fold symmetric molecule. Banana is a monocot, and the three motifs have not diverged enough to obliterate sequence similarity among them. Two Greek key motifs in it carry one primary binding site each. A common secondary binding site exists on the third Greek key. Modelling shows that both the primary sites can support 1-2, 1-3, and 1-6 linked mannosides with the second residue interacting in each case primarily with the secondary binding site. Modelling also readily leads to a bound branched mannopentose with the nonreducing ends of the two branches anchored at the two primary binding sites, providing a structural explanation for the lectin's specificity for branched alpha-mannans. A comparison of the dimeric banana lectin with other beta-prism I fold lectins, provides interesting insights into the variability in their quaternary structure.

  18. Common skate (Raja kenojei) secretes pentraxin into the cutaneous secretion: The first skin mucus lectin in cartilaginous fish.

    Science.gov (United States)

    Tsutsui, Shigeyuki; Yamaguchi, Motoki; Hirasawa, Ai; Nakamura, Osamu; Watanabe, Tasuku

    2009-08-01

    A lactose-specific lectin with a molecular mass of about 25 kDa was purified from the skin mucus of a cartilaginous fish-the common skate (Raja kenojei). The complementary DNA sequence of the lectin was 1540 bp long and contained a reading frame encoding 226 amino acids, which showed approximately 38% identity to pentraxins of mammals and teleosts. Gene expression was observed in the skin, gill, stomach and intestine in the healthy skate. We also identified an isotype gene from the liver whose deduced amino-acid sequence shared 69.0% identity with the skin type gene. The antiserum detected protein in the skin, where the lectin is localized in the epidermal cells, and in the blood plasma. The lectin genes are multicopied in the common skate genome. Although pentraxins are acute phase proteins, mRNAs of both the isotypes were not upregulated after the in vivo challenge with formalin-killed Escherichia coli, which suggests that they are constantly present in the skin mucus and blood plasma to protect against pathogenic invasion. This lectin is the fifth type of lectin found in the cutaneous secretions of fish, demonstrating that skin mucus lectins have evolved with marked molecular diversity in fish.

  19. Self-Assembled Complexes of Horseradish Peroxidase with Magnetic Nanoparticles Showing Enhanced Peroxidase Activity

    KAUST Repository

    Corgié, Stéphane C.

    2012-02-15

    Bio-nanocatalysts (BNCs) consisting of horseradish peroxidase (HRP) self-assembled with magnetic nanoparticles (MNPs) enhance enzymatic activity due to the faster turnover and lower inhibition of the enzyme. The size and magnetization of the MNPs affect the formation of the BNCs, and ultimately control the activity of the bound enzymes. Smaller MNPs form small clusters with a low affinity for the HRP. While the turnover for the bound fraction is drastically increased, there is no difference in the H 2O 2 inhibitory concentration. Larger MNPs with a higher magnetization aggregate in larger clusters and have a higher affinity for the enzyme and a lower substrate inhibition. All of the BNCs are more active than the free enzyme or the MNPs (BNCs > HRP ≤laquo; MNPs). Since the BNCs show surprising resilience in various reaction conditions, they may pave the way towards new hybrid biocatalysts with increased activities and unique catalytic properties for magnetosensitive enzymatic reactions. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Task activation and functional connectivity show concordant memory laterality in temporal lobe epilepsy.

    Science.gov (United States)

    Sideman, Noah; Chaitanya, Ganne; He, Xiaosong; Doucet, Gaelle; Kim, Na Young; Sperling, Michael R; Sharan, Ashwini D; Tracy, Joseph I

    2018-04-01

    In epilepsy, asymmetries in the organization of mesial temporal lobe (MTL) functions help determine the cognitive risk associated with procedures such as anterior temporal lobectomy. Past studies have investigated the change/shift in a visual episodic memory laterality index (LI) in mesial temporal lobe structures through functional magnetic resonance imaging (fMRI) task activations. Here, we examine whether underlying task-related functional connectivity (FC) is concordant with such standard fMRI laterality measures. A total of 56 patients with temporal lobe epilepsy (TLE) (Left TLE [LTLE]: 31; Right TLE [RTLE]: 25) and 34 matched healthy controls (HC) underwent fMRI scanning during performance of a scene encoding task (SET). We assessed an activation-based LI of the hippocampal gyrus (HG) and parahippocampal gyrus (PHG) during the SET and its correspondence with task-related FC measures. Analyses involving the HG and PHG showed that the patients with LTLE had a consistently higher LI (right-lateralized) than that of the HC and group with RTLE, indicating functional reorganization. The patients with RTLE did not display a reliable contralateral shift away from the pathology, with the mesial structures showing quite distinct laterality patterns (HG, no laterality bias; PHG, no evidence of LI shift). The FC data for the group with LTLE provided confirmation of reorganization effects, revealing that a rightward task LI may be based on underlying connections between several left-sided regions (middle/superior occipital and left medial frontal gyri) and the right PHG. The FCs between the right HG and left anterior cingulate/medial frontal gyri were also observed in LTLE. Importantly, the data demonstrate that the areas involved in the LTLE task activation shift to the right hemisphere showed a corresponding increase in task-related FCs between the hemispheres. Altered laterality patterns based on mesial temporal lobe epilepsy (MTLE) pathology manifest as several

  1. Effects of plant lectin from cobra lily, Arisaema curvatum Kunth on development of melon fruit fly, Bactrocera cucurbitae (Coq.).

    Science.gov (United States)

    Singh, Kuljinder; Kaur, Manpreet; Rup, Pushpinder J; Singh, Jatinder

    2008-11-01

    The lectin from tubers of cobra lily, Arisaema curvatum Kunth was purified by affinity chromatography using asialofetuin-linked amino activated porous silica beads. The concentration dependent effect of lectin was studied on second instar larvae (64-72 hr) of Bactrocera cucurbitae (Coq.). The treatment not only resulted in a significant reduction in the percentage pupation and emergence of the adults from treated larvae but it also prolonged the remaining larval development period. A very low LC50 value, 39 mgl(-1) of lectin was obtained on the basis of adult emergence using probit analysis. The activity of three hydrolase enzymes (esterases, acid and alkaline phosphatases), one oxidoreductase (catalase) and one group transfer enzyme (GSTs: Glutathione S-transferases) was assayed in second instar larvae under the influence of the LC50 of lectin at increasing exposure intervals (0, 24, 48 and 72 hr). The Arisaema curvatum lectin significantly decreased the activity of all the enzymes except for esterases, where the activity increased as compared to control at all exposure intervals. The decrease in pupation and emergence as well as significant suppression in the activities of two hydrolases, one oxidoreductase and one GST enzyme in treated larvae of B. cucurbitae indicated that this lectin has anti-metabolic effect on the melon fruit fly larvae.

  2. Structure prediction and functional analysis of a non-permutated lectin from Dioclea grandiflora.

    Science.gov (United States)

    de Sousa, Bruno Lopes; Nagano, Celso Shiniti; Simões, Rafael da Conceição; Silva-Filho, José Caetano; Cunha, Rodrigo Maranguape da Silva; Cajazeiras, João Batista; do Nascimento, Kyria Santiago; Cavada, Benildo Sousa

    2016-12-01

    Legume lectins have been widely studied and applied for many purposes in the last few decades, but many of their physiological aspects remain elusive. The Diocleinae legume subtribe, which includes intensively explored lectins, such as ConA, presents an unusual and extensive post-translational process which results in minor alterations in protein structure, in turn making its function elusive. Despite previous reports about Diocleinae precursor activity, no structural or functional analyses have ever been carried out to understand the impacts of post-translational processing relative to lectin structure and binding specificity. Here we analyzed the functionality of a non glycosylated, recombinantly expressed lectin precursor from Dioclea grandiflora through inhibition assays, corroborating the experimental data with structural information generated by molecular modeling, docking calculations and molecular dynamics simulations. We demonstrate that Diocleinae precursors are active and share the same carbohydrate specificity as mature lectins. At the same time, however, subtle structural alterations were detected and mostly result in an "incomplete" functionality of the precursor, as consequence of an immature binding site and an unstructured tetramer interface, affecting carbohydrate binding and oligomer formation, respectively. Copyright © 2016 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  3. Novel ruthenium methylcyclopentadienyl complex bearing a bipyridine perfluorinated ligand shows strong activity towards colorectal cancer cells.

    Science.gov (United States)

    Teixeira, Ricardo G; Brás, Ana Rita; Côrte-Real, Leonor; Tatikonda, Rajendhraprasad; Sanches, Anabela; Robalo, M Paula; Avecilla, Fernando; Moreira, Tiago; Garcia, M Helena; Haukka, Matti; Preto, Ana; Valente, Andreia

    2018-01-01

    Three new compounds have been synthesized and completely characterized by analytical and spectroscopic techniques. The new bipyridine-perfluorinated ligand L1 and the new organometallic complex [Ru(η 5 -MeCp)(PPh 3 ) 2 Cl] (Ru1) crystalize in the centrosymmetric triclinic space group P1¯. Analysis of the phenotypic effects induced by both organometallic complexes Ru1 and [Ru(η 5 -MeCp)(PPh 3 )(L1)][CF 3 SO 3 ] (Ru2), on human colorectal cancer cells (SW480 and RKO) survival, showed that Ru2 has a potent anti-proliferative activity, 4-6 times higher than cisplatin, and induce apoptosis in these cells. Data obtained in a noncancerous cell line derived from normal colon epithelial cells (NCM460) revealed an intrinsic selectivity of Ru2 for malignant cells at low concentrations, showing the high potential of this compound as a selective anticancer agent. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  4. Critical role for cross-linking of trimeric lectin domains of surfactant protein D in antiviral activity against influenza A virus

    DEFF Research Database (Denmark)

    Tecle, Tesfaldet; White, Mitchell R; Sørensen, Grith Lykke

    2008-01-01

    binding activity for some ligands and mediate some functional activities. The lung collectin SP-D (surfactant protein D) has strong neutralizing activity for IAVs (influenza A viruses) in vitro and in vivo, however, the NCRD derived from SP-D has weak viral-binding ability and lacks neutralizing activity...

  5. Tannic acid modified silver nanoparticles show antiviral activity in herpes simplex virus type 2 infection.

    Directory of Open Access Journals (Sweden)

    Piotr Orlowski

    Full Text Available The interaction between silver nanoparticles and herpesviruses is attracting great interest due to their antiviral activity and possibility to use as microbicides for oral and anogenital herpes. In this work, we demonstrate that tannic acid modified silver nanoparticles sized 13 nm, 33 nm and 46 nm are capable of reducing HSV-2 infectivity both in vitro and in vivo. The antiviral activity of tannic acid modified silver nanoparticles was size-related, required direct interaction and blocked virus attachment, penetration and further spread. All tested tannic acid modified silver nanoparticles reduced both infection and inflammatory reaction in the mouse model of HSV-2 infection when used at infection or for a post-infection treatment. Smaller-sized nanoparticles induced production of cytokines and chemokines important for anti-viral response. The corresponding control buffers with tannic acid showed inferior antiviral effects in vitro and were ineffective in blocking in vivo infection. Our results show that tannic acid modified silver nanoparticles are good candidates for microbicides used in treatment of herpesvirus infections.

  6. Engineered P450 biocatalysts show improved activity and regio-promiscuity in aromatic nitration.

    Science.gov (United States)

    Zuo, Ran; Zhang, Yi; Jiang, Chao; Hackett, John C; Loria, Rosemary; Bruner, Steven D; Ding, Yousong

    2017-04-12

    Nitroaromatics are among the most important and commonly used chemicals but their production often suffers from multiple unsolved challenges. We have previously described the development of biocatalytic nitration processes driven by an engineered P450 TxtE fusion construct. Herein we report the creation of improved nitration biocatalysts through constructing and characterizing fusion proteins of TxtE with the reductase domain of CYP102A1 (P450BM3, BM3R). The majority of constructs contained variable linker length while one was rationally designed for optimizing protein-protein interactions. Detailed biochemical characterization identified multiple active chimeras that showed improved nitration activity, increased coupling efficiency and higher total turnover numbers compared with TxtE. Substrate promiscuity of the most active chimera was further assessed with a substrate library. Finally, a biocatalytic nitration process was developed to nitrate 4-Me-DL-Trp. The production of both 4-Me-5-NO 2 -L-Trp and 4-Me-7-NO 2 -L-Trp uncovered remarkable regio-promiscuity of nitration biocatalysts.

  7. Nav 1.8-null mice show stimulus-dependent deficits in spinal neuronal activity

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    Wood John N

    2006-02-01

    Full Text Available Abstract Background The voltage gated sodium channel Nav 1.8 has a highly restricted expression pattern to predominantly nociceptive peripheral sensory neurones. Behaviourally Nav 1.8-null mice show an increased acute pain threshold to noxious mechanical pressure and also deficits in inflammatory and visceral, but not neuropathic pain. Here we have made in vivo electrophysiology recordings of dorsal horn neurones in intact anaesthetised Nav 1.8-null mice, in response to a wide range of stimuli to further the understanding of the functional roles of Nav 1.8 in pain transmission from the periphery to the spinal cord. Results Nav 1.8-null mice showed marked deficits in the coding by dorsal horn neurones to mechanical, but not thermal, -evoked responses over the non-noxious and noxious range compared to littermate controls. Additionally, responses evoked to other stimulus modalities were also significantly reduced in Nav 1.8-null mice where the reduction observed to pinch > brush. The occurrence of ongoing spontaneous neuronal activity was significantly less in mice lacking Nav 1.8 compared to control. No difference was observed between groups in the evoked activity to electrical activity of the peripheral receptive field. Conclusion This study demonstrates that deletion of the sodium channel Nav 1.8 results in stimulus-dependent deficits in the dorsal horn neuronal coding to mechanical, but not thermal stimuli applied to the neuronal peripheral receptive field. This implies that Nav 1.8 is either responsible for, or associated with proteins involved in mechanosensation.

  8. Complementary Roles of the Classical and Lectin Complement Pathways in the Defense against Aspergillus fumigatus

    DEFF Research Database (Denmark)

    Rosbjerg, Anne; Genster, Ninette; Pilely, Katrine

    2016-01-01

    Aspergillus fumigatus infections are associated with a high mortality rate for immunocompromised patients. The complement system is considered to be important in protection against this fungus, yet the course of activation is unclear. The aim of this study was to unravel the role of the classical......, lectin, and alternative pathways under both immunocompetent and immunocompromised conditions to provide a relevant dual-perspective on the response against A. fumigatus. Conidia (spores) from a clinical isolate of A. fumigatus were combined with various human serum types (including serum deficient...... complement on A. fumigatus, but required classical and/or lectin pathway for initiation. In normal human serum, this initiation came primarily from the classical pathway. However, with a dysfunctional classical pathway (C1q-deficient serum), lectin pathway activated complement and mediated opsonophagocytosis...

  9. Soybean Lectin Enhances Biofilm Formation by Bradyrhizobium japonicum in the Absence of Plants

    Directory of Open Access Journals (Sweden)

    Julieta Pérez-Giménez

    2009-01-01

    Full Text Available Soybean lectin (SBL purified from soybean seeds by affinity chromatography strongly bound to Bradyrhizobium japonicum USDA 110 cell surface. This lectin enhanced biofilm formation by B. japonicum in a concentration-dependent manner. Presence of galactose during biofilm formation had different effects in the presence or absence of SBL. Biofilms were completely inhibited in the presence of both SBL and galactose, while in the absence of SBL, galactose was less inhibitory. SBL was very stable, since its agglutinating activity of B. japonicum cells as well as of human group A+ erythrocytes was resistant to preincubation for one week at 60°C. Hence, we propose that plant remnants might constitute a source of this lectin, which might remain active in soil and thus favor B. japonicum biofilm formation in the interval between soybean crop seasons.

  10. Lectin immunohistochemical evaluation of human bladder carcinomas. A comparison of Carnoy's and formalin fixation.

    Science.gov (United States)

    Okamura, T; Ueda, K; Ohtaguro, K; Inoue, K; Washida, H; Mori, M; Tatemoto, Y; Fukushima, S

    1993-10-01

    A lectin immunohistochemical analysis of 51 human bladder carcinomas, including 44 cases of transitional cell carcinoma (TCC) (G1, 15 cases; G2, 17 cases; G3, 12 cases) and 7 cases of squamous cell carcinoma (SCC), was performed. Tissues were obtained by cold punch biopsies, fixed in Carnoy's or 10% formalin solution, stained for binding of 10 different lectins, and evaluated under the light microscope. The lectins used were concanavalin agglutinin (Con A), soybean agglutinin (SBA), Lotus tetragonolobus agglutinin (LTA), Dolichos biflorusa agglutinin (DBA), peanut agglutinin (PNA), Ricinus communis agglutinin I (RCA1), Ulex europaeus agglutinin I, II (UEA-I, II), wheat germ agglutinin (WGA), and Pisum sativum agglutinin (PEA). TCC prepared with Carnoy's fixation tended to show moderately positive Con A, UEA-I, and WGA reactions for G1, and strongly positive reactions for G2 and G3 lesions. UEA-II was mainly negative in G1, but tended to increase to become moderate in G3. DBA tended to show a moderately positive reaction in G1 and G2, but was mainly negative in G3. With formalin fixation, only RCA1 demonstrated grade specific variation, tendency to react moderately in the G1 and G2 cases, and strongly in G3. There were no further differences among the histopathological grades of TCC for other lectins. Thus, Carnoy's fixation appears superior for distinguishing between grades of lesions. SCC tended to react more strongly than TCC with all the various lectins except PEA, independent of fixation.

  11. Visualisation of lectin binding sites on the surface of human platelets using lectins adsorbed to gold granules.

    Science.gov (United States)

    Nurden, A T; Horisberger, M; Savariau, E; Caen, J P

    1980-10-15

    Washed human platelets have been incubated with the lectins WGA, ConA and RCA1, adsorbed to different-sized gold particles. Plasma membrane receptors for each lectin were then located by scanning and transmission electron microscopy.

  12. Lectin histochemistry of goblet cell sugar residues in the gut of the chick embryo and of the newborn.

    Science.gov (United States)

    Bryk, S G; Sgambati, E; Gheri Bryk, G

    1999-04-01

    The anlage of duodenum, ileum and colon were removed from chick embryos of day 8-21 of incubation and from 1-day-old chicks. A battery of seven different horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, Con A, WGA, LTA and UEAI) was used to study the carbohydrate residues of the glycoconjugates in the goblet cells of the three parts of the intestine. The main results can be summarized as follows: differences in lectin binding were absent in the proximal and distal parts of the duodenum, ileum and colon. Lectin histochemistry showed differences among the three intestinal segments for the time of appearance of the oligosaccharides in the goblet mucus. In the colonic goblet cells of 1-day-old chicks, LTA and UEAI lectins showed two different types of linkage of alpha-L-fucose. This is the first demonstration of UEAI reactive sites in Gallus domesticus.

  13. Rapid affinity-purification and physicochemical characterization of pumpkin (Cucurbita maxima) phloem exudate lectin.

    Science.gov (United States)

    Narahari, Akkaladevi; Swamy, Musti J

    2010-04-21

    The chito-oligosaccharide-specific lectin from pumpkin (Cucurbita maxima) phloem exudate has been purified to homogeneity by affinity chromatography on chitin. After SDS/PAGE in the presence of 2-mercaptoethanol, the pumpkin phloem lectin yielded a single band corresponding to a molecular mass of 23.7 kDa, whereas ESI-MS (electrospray ionization MS) gave the molecular masses of the subunit as 24645 Da. Analysis of the CD spectrum of the protein indicated that the secondary structure of the lectin consists of 9.7% alpha-helix, 35.8% beta-sheet, 22.5% beta-turn and 32.3% unordered structure. Saccharide binding did not significantly affect the secondary and tertiary structures of the protein. The haemagglutinating activity of pumpkin phloem lectin was mostly unaffected in the temperature range 4-70 degrees C, but a sharp decrease was seen between 75 and 85 degrees C. Differential scanning calorimetric and CD spectroscopic studies suggest that the lectin undergoes a co-operative thermal unfolding process centred at approx. 81.5 degrees C, indicating that it is a relatively stable protein.

  14. Bauhinia forficata lectin (BfL) induces cell death and inhibits integrin-mediated adhesion on MCF7 human breast cancer cells.

    Science.gov (United States)

    Silva, Mariana C C; de Paula, Cláudia A A; Ferreira, Joana G; Paredes-Gamero, Edgar J; Vaz, Angela M S F; Sampaio, Misako U; Correia, Maria Tereza S; Oliva, Maria Luiza V

    2014-07-01

    Plant lectins have attracted great interest in cancer studies due to their antitumor activities. These proteins or glycoproteins specifically and reversibly bind to different types of carbohydrates or glycoproteins. Breast cancer, which presents altered glycosylation of cell surface glycoproteins, is one of the most frequent malignant diseases in women. In this work, we describe the effect of the lectin Bauhinia forficata lectin (BfL), which was purified from B. forficata Link subsp. forficata seeds, on the MCF7 human breast cancer cellular line, investigating the mechanisms involved in its antiproliferative activity. MCF7 cells were treated with BfL. Viability and adhesion alterations were evaluated using flow cytometry and western blotting. BfL inhibited the viability of the MCF7 cell line but was ineffective on MDA-MB-231 and MCF 10A cells. It inhibits MCF7 adhesion on laminin, collagen I and fibronectin, decreases α1, α6 and β1 integrin subunit expression, and increases α5 subunit expression. BfL triggers necrosis and secondary necrosis, with caspase-9 inhibition. It also causes deoxyribonucleic acid (DNA) fragmentation, which leads to cell cycle arrest in the G2/M phase and a decrease in the expression of the regulatory proteins pRb and p21. BfL shows selective cytotoxic effect and adhesion inhibition on MCF7 breast cancer cells. Cell death induction and inhibition of cell adhesion may contribute to understanding the action of lectins in breast cancer. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Experimental evidence showing that no mitotically active female germline progenitors exist in postnatal mouse ovaries.

    Science.gov (United States)

    Zhang, Hua; Zheng, Wenjing; Shen, Yan; Adhikari, Deepak; Ueno, Hiroo; Liu, Kui

    2012-07-31

    It has been generally accepted for more than half a century that, in most mammalian species, oocytes cannot renew themselves in postnatal or adult life, and that the number of oocytes is already fixed in fetal or neonatal ovaries. This assumption, however, has been challenged over the past decade. In this study, we have taken an endogenous genetic approach to this question and generated a multiple fluorescent Rosa26(rbw/+);Ddx4-Cre germline reporter mouse model for in vivo and in vitro tracing of the development of female germline cell lineage. Through live cell imaging and de novo folliculogenesis experiments, we show that the Ddx4-expressing cells from postnatal mouse ovaries did not enter mitosis, nor did they contribute to oocytes during de novo folliculogenesis. Our results provide evidence that supports the traditional view that no postnatal follicular renewal occurs in mammals, and no mitotically active Ddx4-expressing female germline progenitors exist in postnatal mouse ovaries.

  16. Etoposide Incorporated into Camel Milk Phospholipids Liposomes Shows Increased Activity against Fibrosarcoma in a Mouse Model

    Directory of Open Access Journals (Sweden)

    Hamzah M. Maswadeh

    2015-01-01

    Full Text Available Phospholipids were isolated from camel milk and identified by using high performance liquid chromatography and gas chromatography-mass spectrometry (GC/MS. Anticancer drug etoposide (ETP was entrapped in liposomes, prepared from camel milk phospholipids, to determine its activity against fibrosarcoma in a murine model. Fibrosarcoma was induced in mice by injecting benzopyrene (BAP and tumor-bearing mice were treated with various formulations of etoposide, including etoposide entrapped camel milk phospholipids liposomes (ETP-Cam-liposomes and etoposide-loaded DPPC-liposomes (ETP-DPPC-liposomes. The tumor-bearing mice treated with ETP-Cam-liposomes showed slow progression of tumors and increased survival compared to free ETP or ETP-DPPC-liposomes. These results suggest that ETP-Cam-liposomes may prove to be a better drug delivery system for anticancer drugs.

  17. Substituted aminopyrimidine protein kinase B (PknB) inhibitors show activity against Mycobacterium tuberculosis

    Science.gov (United States)

    Chapman, Timothy M.; Bouloc, Nathalie; Buxton, Roger S.; Chugh, Jasveen; Lougheed, Kathryn E.A.; Osborne, Simon A.; Saxty, Barbara; Smerdon, Stephen J.; Taylor, Debra L.; Whalley, David

    2012-01-01

    A high-throughput screen against PknB, an essential serine–threonine protein kinase present in Mycobacterium tuberculosis (M. tuberculosis), allowed the identification of an aminoquinazoline inhibitor which was used as a starting point for SAR investigations. Although a significant improvement in enzyme affinity was achieved, the aminoquinazolines showed little or no cellular activity against M. tuberculosis. However, switching to an aminopyrimidine core scaffold and the introduction of a basic amine side chain afforded compounds with nanomolar enzyme binding affinity and micromolar minimum inhibitory concentrations against M. tuberculosis. Replacement of the pyrazole head group with pyridine then allowed equipotent compounds with improved selectivity against a human kinase panel to be obtained. PMID:22469702

  18. The C-type lectin OCILRP2 costimulates EL4 T cell activation via the DAP12-Raf-MAP kinase pathway.

    Science.gov (United States)

    Lou, Qiang; Zhang, Wei; Liu, Guangchao; Ma, Yuanfang

    2014-01-01

    OCILRP2 is a typical Type-II transmembrane protein that is selectively expressed in activated T lymphocytes, dendritic cells, and B cells and functions as a novel co-stimulator of T cell activation. However, the signaling pathways underlying OCILRP2 in T cell activation are still not completely understood. In this study, we found that the knockdown of OCILRP2 expression with shRNA or the blockage of its activity by an anti-OCILRP2 antagonist antibody reduced CD3/CD28-costimulated EL4 T cell viability and IL-2 production, inhibit Raf1, MAPK3, and MAPK8 activation, and impair NFAT and NF-κB transcriptional activities. Furthermore, immunoprecipitation results indicated that OCILRP2 could interact with the DAP12 protein, an adaptor containing an intracellular ITAM motif that can transduce signals to induce MAP kinase activation for T cell activation. Our data reveal that after binding with DAP12, OCILRP2 activates the Raf-MAP kinase pathways, resulting in T cell activation.

  19. The C-type lectin OCILRP2 costimulates EL4 T cell activation via the DAP12-Raf-MAP kinase pathway.

    Directory of Open Access Journals (Sweden)

    Qiang Lou

    Full Text Available OCILRP2 is a typical Type-II transmembrane protein that is selectively expressed in activated T lymphocytes, dendritic cells, and B cells and functions as a novel co-stimulator of T cell activation. However, the signaling pathways underlying OCILRP2 in T cell activation are still not completely understood. In this study, we found that the knockdown of OCILRP2 expression with shRNA or the blockage of its activity by an anti-OCILRP2 antagonist antibody reduced CD3/CD28-costimulated EL4 T cell viability and IL-2 production, inhibit Raf1, MAPK3, and MAPK8 activation, and impair NFAT and NF-κB transcriptional activities. Furthermore, immunoprecipitation results indicated that OCILRP2 could interact with the DAP12 protein, an adaptor containing an intracellular ITAM motif that can transduce signals to induce MAP kinase activation for T cell activation. Our data reveal that after binding with DAP12, OCILRP2 activates the Raf-MAP kinase pathways, resulting in T cell activation.

  20. The reverse transcription inhibitor abacavir shows anticancer activity in prostate cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Francesca Carlini

    Full Text Available BACKGROUND: Transposable Elements (TEs comprise nearly 45% of the entire genome and are part of sophisticated regulatory network systems that control developmental processes in normal and pathological conditions. The retroviral/retrotransposon gene machinery consists mainly of Long Interspersed Nuclear Elements (LINEs-1 and Human Endogenous Retroviruses (HERVs that code for their own endogenous reverse transcriptase (RT. Interestingly, RT is typically expressed at high levels in cancer cells. Recent studies report that RT inhibition by non-nucleoside reverse transcriptase inhibitors (NNRTIs induces growth arrest and cell differentiation in vitro and antagonizes growth of human tumors in animal model. In the present study we analyze the anticancer activity of Abacavir (ABC, a nucleoside reverse transcription inhibitor (NRTI, on PC3 and LNCaP prostate cancer cell lines. PRINCIPAL FINDINGS: ABC significantly reduces cell growth, migration and invasion processes, considerably slows S phase progression, induces senescence and cell death in prostate cancer cells. Consistent with these observations, microarray analysis on PC3 cells shows that ABC induces specific and dose-dependent changes in gene expression, involving multiple cellular pathways. Notably, by quantitative Real-Time PCR we found that LINE-1 ORF1 and ORF2 mRNA levels were significantly up-regulated by ABC treatment. CONCLUSIONS: Our results demonstrate the potential of ABC as anticancer agent able to induce antiproliferative activity and trigger senescence in prostate cancer cells. Noteworthy, we show that ABC elicits up-regulation of LINE-1 expression, suggesting the involvement of these elements in the observed cellular modifications.

  1. Boehmenan, a lignan from Hibiscus ficulneus, showed Wnt signal inhibitory activity.

    Science.gov (United States)

    Shono, Takumi; Ishikawa, Naoki; Toume, Kazufumi; Arai, Midori A; Ahmed, Firoj; Sadhu, Samir K; Ishibashi, Masami

    2015-07-15

    The Wnt signal pathway modulates numerous biological processes, and its aberrant activation is related to various diseases. Therefore, inhibition of the Wnt signal may provide an effective (or efficient) strategy for these diseases. Cell-based luciferase assay targeting the Wnt signal (TOP assay) revealed that Hibiscus ficulneus extract inhibited the Wnt signal. The activity-guided isolation of the MeOH extract of H. ficulneus stems yielded four known (1-4) lignans along with myriceric acid (5). Compounds 1-4 potently inhibited the Wnt signal with TOPflash IC50 values of 1.0, 4.5, 6.3, and 1.9 μM, respectively. Compound 1 exhibited cytotoxicity against both Wnt-dependent (HCT116) and Wnt-independent (RKO) cells. Western blot analysis showed that 1 decreased the expression of full, cytosolic and nuclear β-catenin along with c-myc in STF/293 cells. Our results suggested that 1 may have inhibited the Wnt signal by decreasing β-catenin levels. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Calcium phosphate coating containing silver shows high antibacterial activity and low cytotoxicity and inhibits bacterial adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Ando, Yoshiki, E-mail: andoy@jmmc.jp [Division of Microbiology, Department of Pathology and Microbiology, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501 (Japan); Research Department, Japan Medical Materials Corporation, Uemura Nissei Bldg.9F 3-3-31 Miyahara, Yodogawa-ku, Osaka 532-0003 (Japan); Miyamoto, Hiroshi [Division of Microbiology, Department of Pathology and Microbiology, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501 (Japan); Noda, Iwao; Sakurai, Nobuko [Research Department, Japan Medical Materials Corporation, Uemura Nissei Bldg.9F 3-3-31 Miyahara, Yodogawa-ku, Osaka 532-0003 (Japan); Akiyama, Tomonori [Division of Microbiology, Department of Pathology and Microbiology, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501 (Japan); Yonekura, Yutaka; Shimazaki, Takafumi; Miyazaki, Masaki; Mawatari, Masaaki; Hotokebuchi, Takao [Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501 (Japan)

    2010-01-01

    Surgical site infection is one of the serious complications of orthopedic implants. In order to reduce the incidence of implant-associated infections, we developed a novel coating technology of calcium phosphate (CP) containing silver (Ag), designated Ag-CP coating, using a thermal spraying technique. In this study, we evaluated the antibacterial efficacy and biological safety of this coating. In vitro antibacterial activity tests showed that the growths of Escherichia coli, Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) are completely suppressed on Ag-CP coating. In vitro bacterial adherence tests revealed that the number of adherent bacteria on the surface of this coating is significantly less (p < 0.02) than that on the surface of the CP coating. Moreover, the Ag-CP coating completely inhibits MRSA adhesion [<10 colony-forming units (CFU)] when 10{sup 2} CFU MRSA is inoculated. On the other hand, V79 Chinese hamster lung cells were found to grow on the Ag-CP coating as well as on the CP coating in a cytotoxicity test. These results indicate that the Ag-CP coating on the surface of orthopedic implants exhibits antibacterial activity and inhibits bacterial adhesion without cytotoxicity.

  3. Human active X-specific DNA methylation events showing stability across time and tissues

    Science.gov (United States)

    Joo, Jihoon Eric; Novakovic, Boris; Cruickshank, Mark; Doyle, Lex W; Craig, Jeffrey M; Saffery, Richard

    2014-01-01

    The phenomenon of X chromosome inactivation in female mammals is well characterised and remains the archetypal example of dosage compensation via monoallelic expression. The temporal series of events that culminates in inactive X-specific gene silencing by DNA methylation has revealed a ‘patchwork' of gene inactivation along the chromosome, with approximately 15% of genes escaping. Such genes are therefore potentially subject to sex-specific imbalance between males and females. Aside from XIST, the non-coding RNA on the X chromosome destined to be inactivated, very little is known about the extent of loci that may be selectively silenced on the active X chromosome (Xa). Using longitudinal array-based DNA methylation profiling of two human tissues, we have identified specific and widespread active X-specific DNA methylation showing stability over time and across tissues of disparate origin. Our panel of X-chromosome loci subject to methylation on Xa reflects a potentially novel mechanism for controlling female-specific X inactivation and sex-specific dimorphisms in humans. Further work is needed to investigate these phenomena. PMID:24713664

  4. DC-159a Shows Inhibitory Activity against DNA Gyrases of Mycobacterium leprae.

    Science.gov (United States)

    Yamaguchi, Tomoyuki; Yokoyama, Kazumasa; Nakajima, Chie; Suzuki, Yasuhiko

    2016-09-01

    Fluoroquinolones are a class of antibacterial agents used for leprosy treatment. Some new fluoroquinolones have been attracting interest due to their remarkable potency that is reportedly better than that of ofloxacin, the fluoroquinolone currently recommended for treatment of leprosy. For example, DC-159a, a recently developed 8-methoxy fluoroquinolone, has been found to be highly potent against various bacterial species. Nonetheless, the efficacy of DC-159a against Mycobacterium leprae is yet to be examined. To gather data that can support highly effective fluoroquinolones as candidates for new remedies for leprosy treatment, we conducted in vitro assays to assess and compare the inhibitory activities of DC-159a and two fluoroquinolones that are already known to be more effective against M. leprae than ofloxacin. The fluoroquinolone-inhibited DNA supercoiling assay using recombinant DNA gyrases of wild type and ofloxacin-resistant M. leprae revealed that inhibitory activities of DC-159a and sitafloxacin were at most 9.8- and 11.9-fold higher than moxifloxacin. Also the fluoroquinolone-mediated cleavage assay showed that potencies of those drugs were at most 13.5- and 9.8-fold higher than moxifloxacin. In addition, these two drugs retained their inhibitory activities even against DNA gyrases of ofloxacin-resistant M. leprae. The results indicated that DC-159a and sitafloxacin are more effective against wild type and mutant M. leprae DNA gyrases than moxifloxacin, suggesting that these antibacterial drugs can be good candidates that may supersede current fluoroquinolone remedies. DC-159a in particular is very promising because it is classified in a subgroup of fluoroquinolones that is known to be less likely to cause adverse effects. Our results implied that DC-159a is well worth further investigation to ascertain its in vivo effectiveness and clinical safety for humans.

  5. Investigation on interaction of Achatinin, a 9-O-acetyl sialic acid-binding lectin, with lipopolysaccharide in the innate immunity of Achatina fulica snails.

    Science.gov (United States)

    Biswas, C; Sinha, D; Mandal, C

    2000-01-01

    the LPS stimulated amoebocytes and most importantly, by exhibiting a 77% decline in the coagulation of AAL when depleted of Achatinin. Level of Achatinin sharply declined (17-fold) following injection of LPS (20 microg per snail) to the snails, which was reversible by simultaneous injection of LPS and leupeptin implying the presence of LPS-mediated serine protease activity in Achatinin. This was substantiated when purified Achatinin in vitro showed serine protease activity in the presence of LPS followed by its complete blockage in the presence of leupeptin and phenyl methyl sulphonyl fluoride. Therefore, Achatinin, an abundantly available lectin at multiple sites of A. fulica, by virtue of its interaction with LPS, essentially plays a crucial role in the innate immune protection of A. fulica snails.

  6. Unfolding energetics and stability of banana lectin.

    Science.gov (United States)

    Gupta, Garima; Sinha, Sharmistha; Surolia, Avadhesha

    2008-08-01

    The unfolding pathway of banana lectin from Musa paradisiaca was determined by isothermal denaturation induced by the chaotrope GdnCl. The unfolding was found to be a reversible process. The data obtained by isothermal denaturation provided information on conformational stability of banana lectin. The high values of DeltaG of unfolding at various temperatures indicated the strength of intersubunit interactions. It was found that banana lectin is a very stable and denatures at high chaotrope concentrations only. The basis of the stability may be attributed to strong hydrogen bonds of the order 2.5-3.1 A at the dimeric interface along with the presence of water bridges. This is perhaps very unique example in proteins where subunit association is not a consequence of the predominance of hydrophobic interactions. (c) 2008 Wiley-Liss, Inc.

  7. Effect of Chum Salmon Egg Lectin on Tight Junctions in Caco-2 Cell Monolayers

    Directory of Open Access Journals (Sweden)

    Ryo Nemoto

    2015-05-01

    Full Text Available The effect of a chum salmon egg lectin (CSL3 on tight junction (TJ of Caco-2 cell monolayers was investigated. The lectin opened TJ as indicated by the decrease of the transepithelial electrical resistance (TER value and the increase of the permeation of lucifer yellow, which is transported via the TJ-mediated paracellular pathway. The effects of CSL3 were inhibited by the addition of 10 mM L-rhamnose or D-galactose which were specific sugars for CSL3. The lectin increased the intracellular Ca2+ of Caco-2 cell monolayers, that could be inhibited by the addition of L-rhamnose. The fluorescence immunostaining of β-actin in Caco-2 cell monolayers revealed that the cytoskeleton was changed by the CSL3 treatment, suggesting that CSL3 depolymerized β-actin to cause reversible TJ structural and functional disruption. Although Japanese jack bean lectin and wheat germ lectin showed similar effects in the decrease of the TER values and the increase of the intracellular Ca2+, they could not be inhibited by the same concentrations of simple sugars, such as D-glucose and N-acetyl-D-glucosamine.

  8. Differing lectin-binding patterns of malignant melanoma and nevocellular and Spitz nevi.

    Science.gov (United States)

    Kohchiyama, A; Oka, D; Ueki, H

    1987-01-01

    The lectin-binding patterns of primary malignant melanoma, nevocellular nevus, and Spitz nevus were studied on formalin-fixed, paraffin-embedded sections using a series of biotinylated lectins--concanavalin A (ConA), Ricinus communis agglutinin-1 (RCA1), dolichos biflorus agglutinin (DBA), soybean agglutinin (SBA), maclura pomifera agglutinin (MPA), peanut agglutinin (PNA), wheat germ agglutinin (WGA), and Ulex europeus agglutinin-1(UEA1)--and employing the avidin-biotin-peroxidase complex method. In nevocellular and Spitz nevi, all of the nevus cells were positively stained with ConA and RCA1. No positive staining was observed, however, with the other lectins and no change in binding patterns occurred following neuraminidase pretreatment. In malignant melanoma, all of the melanoma cells were positively stained with ConA and RCA1, and some were also stained with MPA, PNA, and WGA. In addition, DBA, SBA, MPA, PNA, and WGA labeled all of the melanoma cells after neuraminidase pretreatment. No positive staining was observed with UEA1 despite neuraminidase pretreatment. The present results showed that malignant melanoma and nevocellular and Spitz nevi have different lectin-binding patterns and different responses to neuraminidase pretreatment. We, therefore, believe that the lectin staining on paraffin-embedded sections can be a useful probe for the differentiation of these diseases.

  9. Piper betle shows antioxidant activities, inhibits MCF-7 cell proliferation and increases activities of catalase and superoxide dismutase

    Directory of Open Access Journals (Sweden)

    Abrahim Noor

    2012-11-01

    Full Text Available Abstract Background Breast cancer is the most common form of cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Piper betle is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effects of P. betle on breast cancer. Due to the current interest in the potential effects of antioxidants from natural products in breast cancer treatment, we investigated the antioxidant activities of the leaves of P. betle and its inhibitory effect on the proliferation of the breast cancer cell line, MCF-7. Methods The leaves of P. betle were extracted with solvents of varying polarities (water, methanol, ethyl acetate and hexane and their phenolic and flavonoid content were determined using colorimetric assays. Phenolic composition was characterized using HPLC. Antioxidant activities were measured using FRAP, DPPH, superoxide anion, nitric oxide and hyroxyl radical scavenging assays. Biological activities of the extracts were analysed using MTT assay and antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase assays in MCF-7 cells. Results Overall, the ethyl acetate extract showed the highest ferric reducing activity and radical scavenging activities against DPPH, superoxide anion and nitric oxide radicals. This extract also contained the highest phenolic content implying the potential contribution of phenolics towards the antioxidant activities. HPLC analyses revealed the presence of catechin, morin and quercetin in the leaves. The ethyl acetate extract also showed the highest inhibitory effect against the proliferation of MCF-7 cells (IC50=65 μg/ml. Treatment of MCF-7 cells with the plant extract increased activities of catalase and superoxide dismutase. Conclusions Ethyl acetate is the optimal solvent for the extraction of compounds with antioxidant and anti-proliferative activities. The increased activities of catalase and superoxide

  10. Piper betle shows antioxidant activities, inhibits MCF-7 cell proliferation and increases activities of catalase and superoxide dismutase.

    Science.gov (United States)

    Abrahim, Noor Nazirahanie; Kanthimathi, M S; Abdul-Aziz, Azlina

    2012-11-15

    Breast cancer is the most common form of cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Piper betle is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effects of P. betle on breast cancer. Due to the current interest in the potential effects of antioxidants from natural products in breast cancer treatment, we investigated the antioxidant activities of the leaves of P. betle and its inhibitory effect on the proliferation of the breast cancer cell line, MCF-7. The leaves of P. betle were extracted with solvents of varying polarities (water, methanol, ethyl acetate and hexane) and their phenolic and flavonoid content were determined using colorimetric assays. Phenolic composition was characterized using HPLC. Antioxidant activities were measured using FRAP, DPPH, superoxide anion, nitric oxide and hyroxyl radical scavenging assays. Biological activities of the extracts were analysed using MTT assay and antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase) assays in MCF-7 cells. Overall, the ethyl acetate extract showed the highest ferric reducing activity and radical scavenging activities against DPPH, superoxide anion and nitric oxide radicals. This extract also contained the highest phenolic content implying the potential contribution of phenolics towards the antioxidant activities. HPLC analyses revealed the presence of catechin, morin and quercetin in the leaves. The ethyl acetate extract also showed the highest inhibitory effect against the proliferation of MCF-7 cells (IC50=65 μg/ml). Treatment of MCF-7 cells with the plant extract increased activities of catalase and superoxide dismutase. Ethyl acetate is the optimal solvent for the extraction of compounds with antioxidant and anti-proliferative activities. The increased activities of catalase and superoxide dismutase in the treated cells could alter the antioxidant defense

  11. Structural characterization of coagulant Moringa oleifera Lectin and its effect on hemostatic parameters.

    Science.gov (United States)

    Luz, Luciana de Andrade; Silva, Mariana Cristina Cabral; Ferreira, Rodrigo da Silva; Santana, Lucimeire Aparecida; Silva-Lucca, Rosemeire Aparecida; Mentele, Reinhard; Oliva, Maria Luiza Vilela; Paiva, Patricia Maria Guedes; Coelho, Luana Cassandra Breitenbach Barroso

    2013-07-01

    Lectins are carbohydrate recognition proteins. cMoL, a coagulant Moringa oleifera Lectin, was isolated from seeds of the plant. Structural studies revealed a heat-stable and pH resistant protein with 101 amino acids, 11.67 theoretical pI and 81% similarity with a M. oleifera flocculent protein. Secondary structure content was estimated as 46% α-helix, 12% β-sheets, 17% β-turns and 25% unordered structures belonging to the α/β tertiary structure class. cMoL significantly prolonged the time required for blood coagulation, activated partial thromboplastin (aPTT) and prothrombin times (PT), but was not so effective in prolonging aPTT in asialofetuin presence. cMoL acted as an anticoagulant protein on in vitro blood coagulation parameters and at least on aPTT, the lectin interacted through the carbohydrate recognition domain. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Complement activation in leprosy: a retrospective study shows elevated circulating terminal complement complex in reactional leprosy.

    Science.gov (United States)

    Bahia El Idrissi, N; Hakobyan, S; Ramaglia, V; Geluk, A; Morgan, B Paul; Das, P Kumar; Baas, F

    2016-06-01

    Mycobacterium leprae infection gives rise to the immunologically and histopathologically classified spectrum of leprosy. At present, several tools for the stratification of patients are based on acquired immunity markers. However, the role of innate immunity, particularly the complement system, is largely unexplored. The present retrospective study was undertaken to explore whether the systemic levels of complement activation components and regulators can stratify leprosy patients, particularly in reference to the reactional state of the disease. Serum samples from two cohorts were analysed. The cohort from Bangladesh included multi-bacillary (MB) patients with (n = 12) or without (n = 46) reaction (R) at intake and endemic controls (n = 20). The cohort from Ethiopia included pauci-bacillary (PB) (n = 7) and MB (n = 23) patients without reaction and MB (n = 15) patients with reaction. The results showed that the activation products terminal complement complex (TCC) (P ≤ 0·01), C4d (P ≤ 0·05) and iC3b (P ≤ 0·05) were specifically elevated in Bangladeshi patients with reaction at intake compared to endemic controls. In addition, levels of the regulator clusterin (P ≤ 0·001 without R; P < 0·05 with R) were also elevated in MB patients, irrespective of a reaction. Similar analysis of the Ethiopian cohort confirmed that, irrespective of a reaction, serum TCC levels were increased significantly in patients with reactions compared to patients without reactions (P ≤ 0·05). Our findings suggests that serum TCC levels may prove to be a valuable tool in diagnosing patients at risk of developing reactions. © 2016 British Society for Immunology.

  13. Macrophage galactose-type C-type lectin receptor for DC targeting of antitumor glycopeptide vaccines

    DEFF Research Database (Denmark)

    Nuti, M; Zizzari, I; Napoletano, C

    2011-01-01

    e13528 Background: Dendritic cells (DCs) are the most potent antigen presenting cells and are employed in cancer vaccination. Several receptors are being studied in order to identif strategies to increase DCs activating capacity. The C-type lectin macrophage galactose type C-type lectin (MGL...... of IFNg and IL-2 secretion by both CD8 and CD4 T cells. CONCLUSIONS: These results demonstrate that MGL engagement profoundly affects DC plasticity inducing and directing a Th1 immune response. Moreover, MGL receptor expressed on human DC can be targeted by glycopeptide based vaccines with adjuvant...

  14. Chemical modification of the lectin of the marine coral Gerardia savaglia by marine quinone avarone

    Directory of Open Access Journals (Sweden)

    IVANA PAJIC

    2007-12-01

    Full Text Available The quinone avarone, isolated from the marine sponge Dysidea avara, possesses the ability to chemically modify proteins. In this work, modification of lectin isolated from the coral Gerardia savaglia by avarone was examined. The techniques used for studying the modification were: SDS PAGE, isoelectric focusing and hemagglutination testing. The results of the SDS PAGE indicate dimerization of the protein. A shift of the pI toward lower value occurs upon modification. The change of the hemagglutination activity of the protein confirms that chemical modification of G. savaglia lectin by avarone changes its ability to interact with the membrane of erythrocytes.

  15. Diterpenes from buds of Wikstroemia chamaedaphne showing anti-hepatitis B virus activities.

    Science.gov (United States)

    Li, Shi-Fei; Jiao, Ying-Ying; Zhang, Zhi-Qiang; Chao, Jian-Bin; Jia, Jie; Shi, Xun-Long; Zhang, Li-Wei

    2018-07-01

    Phytochemical study of the buds of Wikstroemia chamaedaphne Meisn. led to the isolation of seven previously undescribed diterpenes, including one tigliane diterpene (wikstchalide A), two daphnane diterpenes (wikstroelides W-X), and four lathyrane diterpenes (laurifoliosides A-B and 2-epi-laurifoliosides A-B), along with four known diterpenes. The structures of these compounds were established by extensive spectroscopic evidence and electronic circular dichroism (ECD) calculations. Wikstchalide A possesses a 5,6-epoxy ring in the tigliane skeleton. Two compounds exhibited potential anti-hepatitis B virus activities, with IC 50 values of 46.5 and 88.3 μg/mL against hepatitis B virus (HBV) surface antigen (HBsAg), and six compounds showed certain inhibitory effects on HBV-DNA replication with the inhibition ratios ranging from 2.0% to 33.0% at the concentrations ranging from 0.39 to 6.25 μg/mL. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Rewiring monocyte glucose metabolism via C-type lectin signaling protects against disseminated candidiasis.

    Science.gov (United States)

    Domínguez-Andrés, Jorge; Arts, Rob J W; Ter Horst, Rob; Gresnigt, Mark S; Smeekens, Sanne P; Ratter, Jacqueline M; Lachmandas, Ekta; Boutens, Lily; van de Veerdonk, Frank L; Joosten, Leo A B; Notebaart, Richard A; Ardavín, Carlos; Netea, Mihai G

    2017-09-01

    Monocytes are innate immune cells that play a pivotal role in antifungal immunity, but little is known regarding the cellular metabolic events that regulate their function during infection. Using complementary transcriptomic and immunological studies in human primary monocytes, we show that activation of monocytes by Candida albicans yeast and hyphae was accompanied by metabolic rewiring induced through C-type lectin-signaling pathways. We describe that the innate immune responses against Candida yeast are energy-demanding processes that lead to the mobilization of intracellular metabolite pools and require induction of glucose metabolism, oxidative phosphorylation and glutaminolysis, while responses to hyphae primarily rely on glycolysis. Experimental models of systemic candidiasis models validated a central role for glucose metabolism in anti-Candida immunity, as the impairment of glycolysis led to increased susceptibility in mice. Collectively, these data highlight the importance of understanding the complex network of metabolic responses triggered during infections, and unveil new potential targets for therapeutic approaches against fungal diseases.

  17. PVA-Glutaraldehyde as support for lectin immobilization and affinity chromatography

    Directory of Open Access Journals (Sweden)

    Moacyr Jesus Barreto de Melo Rêgo

    2016-12-01

    Full Text Available Immobilized lectins are a powerful biotechnological tool for separation and isolation of glycoconjugates. In the present study, polyvinyl alcohol (PVA and glutaraldehyde (GA were used as a support for Concanavalin A (Con A covalent immobilization and for entrapment of Parkia pendula seed gum (PpeG. Con A immobilization yielded approximately 30% and 0.6 M glucose solution was the minimum concentration able to elute fetuin from column. PVA-GA-PpeG column was efficiently recognized by pure P. pendula lectin (PpeL. These findings indicate that PVA-GA interpenetrated network showed to be an efficient support for lectin covalent immobilization and as affinity chromatography matrix after trapping of PpeG.

  18. Mice with cancer-induced bone pain show a marked decline in day/night activity

    Directory of Open Access Journals (Sweden)

    Lisa A. Majuta

    2017-10-01

    Conclusion:. Even when the tumor is confined to a single load-bearing bone, CIBP drives a significant loss of activity, which increases with disease progression. Understanding the mechanisms that drive this reduction in activity may allow the development of therapies that allow CIBP patients to better maintain their activity and functional status.

  19. Mu-opioid receptor knockout mice show diminished food-anticipatory activity

    NARCIS (Netherlands)

    Kas, Martien J H; van den Bos, Ruud; Baars, Annemarie M; Lubbers, Marianne; Lesscher, Heidi M B; Hillebrand, Jacquelien J G; Schuller, Alwin G; Pintar, John E; Spruijt, Berry M

    We have previously suggested that during or prior to activation of anticipatory behaviour to a coming reward, mu-opioid receptors are activated. To test this hypothesis schedule induced food-anticipatory activity in mu-opioid receptor knockout mice was measured using running wheels. We hypothesized

  20. Lectin receptor kinase LecRK-b2 localizes to plasma membrane and ...

    African Journals Online (AJOL)

    -b2, has been characterized. Confocal microscopy images showed that the LecRK-b2-GFP fusion protein is localized to plasma membrane. The results of yeast 2 hybrid showed that lectin domain of LecRK-b2 had selfinteraction, while the ...

  1. A L-type lectin gene is involved in the response to hormonal treatment and water deficit in Volkamer lemon.

    Science.gov (United States)

    Vieira, Dayse Drielly Sousa Santana; Emiliani, Giovanni; Bartolini, Paola; Podda, Alessandra; Centritto, Mauro; Luro, François; Carratore, Renata Del; Morillon, Raphaël; Gesteira, Abelmon; Maserti, Biancaelena

    2017-11-01

    Combination of biotic and abiotic stress is a major challenge for crop and fruit production. Thus, identification of genes involved in cross-response to abiotic and biotic stress is of great importance for breeding superior genotypes. Lectins are glycan-binding proteins with a functions in the developmental processes as well as in the response to biotic and abiotic stress. In this work, a lectin like gene, namely ClLectin1, was characterized in Volkamer lemon and its expression was studied in plants exposed to either water stress, hormonal elicitors (JA, SA, ABA) or wounding to understand whether this gene may have a function in the response to multiple stress combination. Results showed that ClLectin1 has 100% homology with a L-type lectin gene from C. sinensis and the in silico study of the 5'UTR region showed the presence of cis-responsive elements to SA, DRE2 and ABA. ClLectin1 was rapidly induced by hormonal treatments and wounding, at local and systemic levels, suggesting an involvement in defence signalling pathways and a possible role as fast detection biomarker of biotic stress. On the other hand, the induction of ClLectin1 by water stress pointed out a role of the gene in the response to drought. The simultaneous response of ClLectin1 expression to water stress and SA treatment could be further investigated to assess whether a moderate drought stress may be useful to improve citrus performance by stimulating the SA-dependent response to biotic stress. Copyright © 2017 Elsevier GmbH. All rights reserved.

  2. Structural basis of carbohydrate recognition by lectin II from Ulex europaeus, a protein with a promiscuous carbohydrate-binding site.

    Science.gov (United States)

    Loris, R; De Greve, H; Dao-Thi, M H; Messens, J; Imberty, A; Wyns, L

    2000-08-25

    Protein-carbohydrate interactions are the language of choice for inter- cellular communication. The legume lectins form a large family of homologous proteins that exhibit a wide variety of carbohydrate specificities. The legume lectin family is therefore highly suitable as a model system to study the structural principles of protein-carbohydrate recognition. Until now, structural data are only available for two specificity families: Man/Glc and Gal/GalNAc. No structural data are available for any of the fucose or chitobiose specific lectins. The crystal structure of Ulex europaeus (UEA-II) is the first of a legume lectin belonging to the chitobiose specificity group. The complexes with N-acetylglucosamine, galactose and fucosylgalactose show a promiscuous primary binding site capable of accommodating both N-acetylglucos amine or galactose in the primary binding site. The hydrogen bonding network in these complexes can be considered suboptimal, in agreement with the low affinities of these sugars. In the complexes with chitobiose, lactose and fucosyllactose this suboptimal hydrogen bonding network is compensated by extensive hydrophobic interactions in a Glc/GlcNAc binding subsite. UEA-II thus forms the first example of a legume lectin with a promiscuous binding site and illustrates the importance of hydrophobic interactions in protein-carbohydrate complexes. Together with other known legume lectin crystal structures, it shows how different specificities can be grafted upon a conserved structural framework. Copyright 2000 Academic Press.

  3. Phylogenetic Analysis of C Type Lectin from Toxocara canis Infective Larvae and Comparison with the C Type Lectin Fam-ily in the Immune System of Mouse and Human

    Directory of Open Access Journals (Sweden)

    Fazeleh ETEBAR

    2018-03-01

    Full Text Available Background: C type lectin (CTL family is a type of calcium-dependent proteins found in vertebrates and invertebrates. The objective of this study was to perform a comparative analysis and phylogenetic inferring for understanding the similarities and differences of carbohydrate recognition domain (CRD domain of Toxocara canis CTL and other nematodes, and similar C type lectin involved in the immune system of mouse and human as their host.Methods: The female T. canis was retrieved from the 2-6 months puppies (Department of Parasitology, Faculty of Veterinary Medicine, University of Tehran, 2015. To collect T. canis eggs, the worms were cultured for 5 d until they were embryonated. The hatching process was accelerated for collecting the stage 2 larvae, and the larvae were cultured for a week. A cDNA library was made from the total mRNA of T. canis infective larvae. The PCR amplification for C type lectin gene was performed and the amino acids were analyzed using the alignment method and the construction of phylogenetic tree.Results: The suspension sample maintained at 30 ºC for four weeks could embryonate 90%-100% of eggs. T. canis CTL gene was 657 bp in length and encoded a protein with 219 amino acids. The CTL of species of Strongylida order were closely placed in the tree, whereas the members of Ascaridida orders were located in a separate branch. High levels of similarity (36%-44% and conservation of C type lectin from T. canis with mouse and human C type lectins. Its C type lectin showed a higher similarity with asialoglycoprotein receptor (ASGPR, macrophage lectin, dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN, MINCLE receptor of mouse and human.Conclusion: Analysis of CRD domain of C type lectin protein could make a better understanding of their role in the interaction of nematode parasite with their hosts.

  4. Mice with cancer-induced bone pain show a marked decline in day/night activity.

    Science.gov (United States)

    Majuta, Lisa A; Guedon, Jean-Marc G; Mitchell, Stefanie A T; Kuskowski, Michael A; Mantyh, Patrick W

    2017-09-01

    Cancer-induced bone pain (CIBP) is the most common type of pain with cancer. In humans, this pain can be difficult to control and highly disabling. A major problem with CIBP in humans is that it increases on weight-bearing and/or movement of a tumor-bearing bone limiting the activity and functional status of the patient. Currently, there is less data concerning whether similar negative changes in activity occur in rodent models of CIBP. To determine whether there are marked changes in activity in a rodent model of CIBP and compare this to changes in skin hypersensitivity. Osteosarcoma cells were injected and confined to 1 femur of the adult male mouse. Every 7 days, spontaneous horizontal and vertical activities were assessed over a 20-hour day and night period using automated activity boxes. Mechanical hypersensitivity of the hind paw skin was assessed using von Frey testing. As the tumor cells grew within the femur, there was a significant decline in horizontal and vertical activity during the times of the day/night when the mice are normally most active. Mice also developed significant hypersensitivity in the skin of the hind paw in the tumor-bearing limb. Even when the tumor is confined to a single load-bearing bone, CIBP drives a significant loss of activity, which increases with disease progression. Understanding the mechanisms that drive this reduction in activity may allow the development of therapies that allow CIBP patients to better maintain their activity and functional status.

  5. Physically Active Men Show Better Semen Parameters than Their Sedentary Counterparts

    OpenAIRE

    Lalinde-Acevedo, Paula C.; Mayorga-Torres, B. Jose Manuel; Agarwal, Ashok; du Plessis, Stefan S.; Ahmad, Gulfam; Cadavid, Ángela P.; Cardona Maya, Walter D.

    2017-01-01

    Background The quality of semen depends upon several factors such as environment, life style, physical activity, age, and occupation. The aim of this study was to analyze and compare the conventional and functional semen parameters in men practicing vigorous physical activity to those of sedentary men. Materials and Methods In this descriptive cross-sectional study, semen samples of 17 physically active men and 15 sedentary men were collected for analysis. Semen analysis was performe...

  6. Glycans: bioactive signals decoded by lectins.

    Science.gov (United States)

    Gabius, Hans-Joachim

    2008-12-01

    The glycan part of cellular glycoconjugates affords a versatile means to build biochemical signals. These oligosaccharides have an exceptional talent in this respect. They surpass any other class of biomolecule in coding capacity within an oligomer (code word). Four structural factors account for this property: the potential for variability of linkage points, anomeric position and ring size as well as the aptitude for branching (first and second dimensions of the sugar code). Specific intermolecular recognition is favoured by abundant potential for hydrogen/co-ordination bonds and for C-H/pi-interactions. Fittingly, an array of protein folds has developed in evolution with the ability to select certain glycans from the natural diversity. The thermodynamics of this reaction profits from the occurrence of these ligands in only a few energetically favoured conformers, comparing favourably with highly flexible peptides (third dimension of the sugar code). Sequence, shape and local aspects of glycan presentation (e.g. multivalency) are key factors to regulate the avidity of lectin binding. At the level of cells, distinct glycan determinants, a result of enzymatic synthesis and dynamic remodelling, are being defined as biomarkers. Their presence gains a functional perspective by co-regulation of the cognate lectin as effector, for example in growth regulation. The way to tie sugar signal and lectin together is illustrated herein for two tumour model systems. In this sense, orchestration of glycan and lectin expression is an efficient means, with far-reaching relevance, to exploit the coding potential of oligosaccharides physiologically and medically.

  7. New crystal forms of Diocleinae lectins in the presence of different dimannosides

    International Nuclear Information System (INIS)

    Moreno, Frederico Bruno Mendes Batista; Bezerra, Gustavo Arruda; Oliveira, Taianá Maia de; Souza, Emmanuel Prata de; Rocha, Bruno Anderson Matias da; Benevides, Raquel Guimarães; Delatorre, Plínio; Cavada, Benildo Sousa; Azevedo, Walter Filgueira Jr de

    2006-01-01

    The crystallization and preliminary X-ray data of Canavalia gladiata lectin (CGL) and C. maritima lectin (CML) complexed with Man(α1-2)Man(α1)OMe, Man(α1-3)Man(α1)OMe and Man(α1-4)Man(α1)OMe in two crystal forms [the complexes with Man(α1-3)Man(α1)OMe and Man(α1-4)Man(α1)OMe crystallized in space group P3 2 and those with Man(α1-2)Man(α1)OMe crystallized in space group I222], which differed from those of the native proteins (P2 1 2 1 2 for CML and C222 for CGL), are reported. Studying the interactions between lectins and sugars is important in order to explain the differences observed in the biological activities presented by the highly similar proteins of the Diocleinae subtribe. Here, the crystallization and preliminary X-ray data of Canavalia gladiata lectin (CGL) and C. maritima lectin (CML) complexed with Man(α1-2)Man(α1)OMe, Man(α1-3)Man(α1)OMe and Man(α1-4)Man(α1)OMe in two crystal forms [the complexes with Man(α1-3)Man(α1)OMe and Man(α1-4)Man(α1)OMe crystallized in space group P3 2 and those with Man(α1-2)Man(α1)OMe crystallized in space group I222], which differed from those of the native proteins (P2 1 2 1 2 for CML and C222 for CGL), are reported. The crystal complexes of ConA-like lectins with Man(α1-4)Man(α1)OMe are reported here for the first time

  8. Characterization and phylogenetic analysis of lectin gene cDNA isolated from sea cucumber ( Apostichopus japonicus) body wall

    Science.gov (United States)

    Xue, Zhuang; Li, Hui; Liu, Yang; Zhou, Wei; Sun, Jing; Wang, Xiuli

    2017-12-01

    As a `living fossil' of species origin and `rich treasure' of food and nutrition development, sea cucumber has received a lot of attentions from researchers. The cDNA library construction and EST sequencing of blood had been conducted previously in our lab. The bioinformatic analysis provided a gene fragment which is highly homologous with the genes of lectin family, named AjL ( Apostichopus japonicus lectin). To characterize and determine the phylogeny of AjL genes in early evolution, we isolated a full-length cDNA of lectin gene from the body wall of A. japonicus. The open reading frame of this gene contained 489 bp and encoded a 163 amino acids secretory protein being homologous to lectins of mammals and aquatic organisms. The deduced protein included a lectin-like domain. SDS-PAGE analysis showed that AjL migrated as a specific band (about 36.09 kDa under reducing), and agglutinated against rabbit red blood cells. AjL was similar to chain A of CEL-IV in space structure. We predicted that AjL may play the same role of CEL-IV. Our results suggested that more than one lectin gene functioned in sea cucumber and most of other species, which was fused by uncertain sequences during the evolution and encoded different proteins with diverse functions. Our findings provided the insights into the function and characteristics of lectin genes invertebrates. The results will also be helpful for the identification and structural, functional, and evolutionary analyses of lectin genes.

  9. Synthesis and biological activity of sulfur compounds showing structural analogy with combretastatin A-4

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Edson dos A. dos; Prado, Paulo C.; Carvalho, Wanderley R. de; Lima, Ricardo V. de; Beatriz, Adilson; Lima, Denis P. de, E-mail: denis.lima@ufms.br [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Departamento de Quimica; Hamel, Ernest [Screening Technologies Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute at Frederick, National Institutes of Health, Frederick, MD (United States); Dyba, Marzena A. [Basic Science Program , SAIC-Frederick, Inc., Structural Biophysics Laboratory National Cancer Institute, Frederick, MD (United States); Albuquerque, Sergio [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas

    2013-09-01

    We extended our previous exploration of sulfur bridges as bioisosteric replacements for atoms forming the bridge between the aromatic rings of combretastatin A-4. Employing coupling reactions between 5-iodo-1,2,3-trimethoxybenzene and substituted thiols, followed by oxidation to sulfones with m-CPBA, different locations for attaching the sulfur atom to ring A through the synthesis of nine compounds were examined. Antitubulin activity was performed with electrophoretically homogenous bovine brain tubulin, and activity occurred with the 1,2,3-trimethoxy-4-[(4-methoxyphenyl)thio]benzene (12), while the other compounds were inactive. The compounds were also tested for leishmanicidal activity using promastigote forms of Leishmania braziliensis (MHOM/BR175/M2904),and the greatest activity was observed with 1,2,3-trimethoxy-4-(phenylthio)benzene (10) and 1,2,3-trimethoxy-4-[(4-methoxyphenyl) sulfinyl]benzene (15). (author)

  10. Self-Assembled Complexes of Horseradish Peroxidase with Magnetic Nanoparticles Showing Enhanced Peroxidase Activity

    KAUST Repository

    Corgié , Sté phane C.; Kahawong, Patarawan; Duan, Xiaonan; Bowser, Daniel; Edward, Joseph B.; Walker, Larry P.; Giannelis, Emmanuel P.

    2012-01-01

    Bio-nanocatalysts (BNCs) consisting of horseradish peroxidase (HRP) self-assembled with magnetic nanoparticles (MNPs) enhance enzymatic activity due to the faster turnover and lower inhibition of the enzyme. The size and magnetization of the MNPs

  11. Regional Brain Activation during Meditation Shows Time and Practice Effects: An Exploratory FMRI Study

    Directory of Open Access Journals (Sweden)

    E. Baron Short

    2010-01-01

    Full Text Available Meditation involves attentional regulation and may lead to increased activity in brain regions associated with attention such as dorsal lateral prefrontal cortex (DLPFC and anterior cingulate cortex (ACC. Using functional magnetic resonance imaging, we examined whether DLPFC and ACC were activated during meditation. Subjects who meditate were recruited and scanned on a 3.0 Tesla scanner. Subjects meditated for four sessions of 12 min and performed four sessions of a 6 min control task. Individual and group t-maps were generated of overall meditation response versus control response and late meditation response versus early meditation response for each subject and time courses were plotted. For the overall group (n = 13, and using an overall brain analysis, there were no statistically significant regional activations of interest using conservative thresholds. A region of interest analysis of the entire group time courses of DLPFC and ACC were statistically more active throughout meditation in comparison to the control task. Moreover, dividing the cohort into short (n = 8 and long-term (n = 5 practitioners (>10 years revealed that the time courses of long-term practitioners had significantly more consistent and sustained activation in the DLPFC and the ACC during meditation versus control in comparison to short-term practitioners. The regional brain activations in the more practised subjects may correlate with better sustained attention and attentional error monitoring. In summary, brain regions associated with attention vary over the time of a meditation session and may differ between long- and short-term meditation practitioners.

  12. Isolation and characterization of pigmented bacteria showing antimicrobial activity from Malaysian marine environment

    Directory of Open Access Journals (Sweden)

    Ahmad, A.

    2013-01-01

    Full Text Available Aims: Natural products play a prominent role in the discovery of leads for the development of drugs in the treatment ofhuman diseases. Much of nature remains to be explored, especially marine and microbial environments.Methodology and results: Fifty-five pigmented marine bacteria were isolated from sponges, seawater, mangrovesediment, sea cucumber and mussel from different coastal area of Malaysia. The antimicrobial activities of thesebacteria were investigated by disk diffusion method against pathogenic bacteria. Out of 55 isolates, 18 isolates exhibitedantimicrobial activity, which based on morphological characterization, 53% of them were Gram positive and 47% wereGram negative. All active isolates were able to tolerate more than 4% NaCl in the nutrient agar medium that indicatedthey were autochthonous to marine environment and moderate salt tolerant in nature. Molecular identification of isolatesby the strong antimicrobial activities indicates that isolates WPRA3 (JX020764 and SM11-3j belong to genus Serratiaand isolate SDPM1 (JQ083392 belongs to genus Zooshikella.Conclusion, significance and impact of study: The results of present study revealed that the active isolates arepotential producer of antimicrobial secondary metabolites and might be utilized as drug candidate.

  13. Bilateral versus ipsilesional cortico-subcortical activity patterns in stroke show hemispheric dependence.

    Science.gov (United States)

    Vidal, Ana C; Banca, Paula; Pascoal, Augusto G; Cordeiro, Gustavo; Sargento-Freitas, João; Gouveia, Ana; Castelo-Branco, Miguel

    2018-01-01

    Background Understanding of interhemispheric interactions in stroke patients during motor control is an important clinical neuroscience quest that may provide important clues for neurorehabilitation. In stroke patients bilateral overactivation in both hemispheres has been interpreted as a poor prognostic indicator of functional recovery. In contrast, ipsilesional patterns have been linked with better motor outcomes. Aim We investigated the pathophysiology of hemispheric interactions during limb movement without and with contralateral restraint, to mimic the effects of constraint-induced movement therapy. We used neuroimaging to probe brain activity with such a movement-dependent interhemispheric modulation paradigm. Methods We used a functional magnetic resonance imaging block design during which the plegic/paretic upper limb was recruited/mobilized to perform unilateral arm elevation, as a function of presence versus absence of contralateral limb restriction (n = 20, with balanced left/right lesion sites). Results Analysis of 10 right hemispheric stroke participants yielded bilateral sensorimotor cortex activation in all movement phases in contrast with the unilateral dominance seen in the 10 left hemispheric stroke participants. Superimposition of contralateral restriction led to a prominent shift from activation to deactivation response patterns, in particular in cortical and basal ganglia motor areas in right hemispheric stroke. Left hemispheric stroke was, in general, characterized by reduced activation patterns, even in the absence of restriction, which induced additional cortical silencing. Conclusion The observed hemispheric-dependent activation/deactivation shifts is novel and these pathophysiological observations suggest short-term neuroplasticity that may be useful for hemisphere-tailored neurorehabilitation.

  14. Lectins, Interconnecting Proteins with Biotechnological/Pharmacological and Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Luana Cassandra Breitenbach Barroso Coelho

    2017-01-01

    Full Text Available Lectins are proteins extensively used in biomedical applications with property to recognize carbohydrates through carbohydrate-binding sites, which identify glycans attached to cell surfaces, glycoconjugates, or free sugars, detecting abnormal cells and biomarkers related to diseases. These lectin abilities promoted interesting results in experimental treatments of immunological diseases, wounds, and cancer. Lectins obtained from virus, microorganisms, algae, animals, and plants were reported as modulators and tool markers in vivo and in vitro; these molecules also play a role in the induction of mitosis and immune responses, contributing for resolution of infections and inflammations. Lectins revealed healing effect through induction of reepithelialization and cicatrization of wounds. Some lectins have been efficient agents against virus, fungi, bacteria, and helminths at low concentrations. Lectin-mediated bioadhesion has been an interesting characteristic for development of drug delivery systems. Lectin histochemistry and lectin-based biosensors are useful to detect transformed tissues and biomarkers related to disease occurrence; antitumor lectins reported are promising for cancer therapy. Here, we address lectins from distinct sources with some biological effect and biotechnological potential in the diagnosis and therapeutic of diseases, highlighting many advances in this growing field.

  15. Lysine and pipecolic acid and some of their derivatives show anticonvulsant activity, and stimulation of benzodiazepine receptor activity

    International Nuclear Information System (INIS)

    Chang, Yung-Feng; Gao, Xue-Min

    1989-01-01

    Benzodiazepines are one of the most widely prescribed drugs in the treatment of anxiety, epilepsy and muscle tension. The natural products lysine and pipecolic acid known to be present in the animal, plant and microorganism, have been shown to be anticonvulsant against pentetrazol (PTZ)-induced seizures in mice. Methyl and ethyl esters of L-lysine and the N-isopropanol derivative of pipecolic acid appear to increase the anticonvulsant potency of the parent compounds, presumably due to their increase in hydrophobicity. Lysine and pipecolic acid showed significant stimulation of specific [ 3 H]flunitrazepam (FZ) binding to mouse brain membranes. This stimulation was enhanced by chloride ions and stereospecific with L-isomer having higher effect. The dose-dependent anticonvulsant activity of lysine and pipecolic acid, and their stimulation of [ 3 H]FZ binding appear to be correlated. The antiepileptic activity lysine, pipecolic acid and their derivatives therefore may be mediated through the γ-aminobutyric acid-benzodiazepine receptor complex

  16. Mannan-Binding Lectin Is Involved in the Protection against Renal Ischemia/Reperfusion Injury by Dietary Restriction.

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    Shushimita Shushimita

    Full Text Available Preoperative fasting and dietary restriction offer robust protection against renal ischemia/reperfusion injury (I/RI in mice. We recently showed that Mannan-binding lectin (MBL, the initiator of the lectin pathway of complement activation, plays a pivotal role in renal I/RI. Based on these findings, we investigated the effect of short-term DR (30% reduction of total food intake or three days of water only fasting on MBL in 10-12 weeks old male C57/Bl6 mice. Both dietary regimens significantly reduce the circulating levels of MBL as well as its mRNA expression in liver, the sole production site of MBL. Reconstitution of MBL abolished the protection afforded by dietary restriction, whereas in the fasting group the protection persisted. These data show that modulation of MBL is involved in the protection against renal I/RI induced by dietary restriction, and suggest that the mechanisms of protection induced by dietary restriction and fasting may be different.

  17. Methanol extract of grain dust shows complement fixing activity and other characteristics similar to tannic acid.

    Science.gov (United States)

    Skea, D; Broder, I

    1986-01-01

    We have found several similarities between tannic acid and grain dust extract prepared with methanol. Both formed a precipitate with IgG, and these interactions were inhibited by albumin. In addition, both preparations fixed complement; this activity was heat stable and was removed by prior adsorption of the preparations with hide powder. Adsorption with polyvinyl polypyrrolidone reduced the complement-fixing activity of tannic acid but not that of the methanol grain dust extract. The similarities between tannic acid and the methanol grain dust extract are consistent with the presence of a tannin or tanninlike material in grain dust. Images FIGURE 1. PMID:3709479

  18. Triazole nucleoside derivatives bearing aryl functionalities on the nucleobases show antiviral and anticancer activity.

    Science.gov (United States)

    Xia, Yi; Qu, Fanqi; Peng, Ling

    2010-08-01

    Synthetic nucleoside mimics are important candidates in the searing for antiviral and anticancer drugs. Ribavirin, the first antiviral nucleoside drug, is unique in its antiviral activity with mutilple modes of action, which are mainly due to its special triazole heterocycle as nucleobase. Additionally, introducing aromatic functionalities to the nucleobase is able to confer novel mechanisms of action for nucleoside mimics. With the aim to combine the special characteristics of unnatural triazole heterocycles with those of the appended aromatic groups on the nucleobases, novel 1,2,4-triazole nucleoside analogs bearing aromatic moieties were designed and developed. The present short review summarizes the molecular design, chemical synthesis and biological activity of these triazole nucleoside analogs. Indeed, the discovery of antiviral and anticancer activities shown by these triazole nucleosides as well as the new mechanism underlying the biological activity by one of the anticancer leads has validated the rationale for molecular design and impacted us to further explore the concept with the aim of developing structurally novel nucleoside drug candidates with new modes of action.

  19. Young Adults with Autism Spectrum Disorder Show Early Atypical Neural Activity during Emotional Face Processing

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    Rachel C. Leung

    2018-02-01

    Full Text Available Social cognition is impaired in autism spectrum disorder (ASD. The ability to perceive and interpret affect is integral to successful social functioning and has an extended developmental course. However, the neural mechanisms underlying emotional face processing in ASD are unclear. Using magnetoencephalography (MEG, the present study explored neural activation during implicit emotional face processing in young adults with and without ASD. Twenty-six young adults with ASD and 26 healthy controls were recruited. Participants indicated the location of a scrambled pattern (target that was presented alongside a happy or angry face. Emotion-related activation sources for each emotion were estimated using the Empirical Bayes Beamformer (pcorr ≤ 0.001 in Statistical Parametric Mapping 12 (SPM12. Emotional faces elicited elevated fusiform, amygdala and anterior insula and reduced anterior cingulate cortex (ACC activity in adults with ASD relative to controls. Within group comparisons revealed that angry vs. happy faces elicited distinct neural activity in typically developing adults; there was no distinction in young adults with ASD. Our data suggest difficulties in affect processing in ASD reflect atypical recruitment of traditional emotional processing areas. These early differences may contribute to difficulties in deriving social reward from faces, ascribing salience to faces, and an immature threat processing system, which collectively could result in deficits in emotional face processing.

  20. Show Me the Way: Future Faculty Prefer Directive Feedback When Trying Active Learning Approaches

    Science.gov (United States)

    Stephens, Jessica D.; Battle, David C.; Gormally, Cara L.; Brickman, Peggy

    2017-01-01

    Early training opportunities for future faculty, namely graduate students and postdoctoral researchers, can better prepare them to use active learning approaches. We know that instructional feedback supports sustained change and motivates instructors to improve teaching practices. Here, we incorporate feedback as a key component of a pedagogical…

  1. Human area MT+ shows load-dependent activation during working memory maintenance with continuously morphing stimulation.

    Science.gov (United States)

    Galashan, Daniela; Fehr, Thorsten; Kreiter, Andreas K; Herrmann, Manfred

    2014-07-11

    Initially, human area MT+ was considered a visual area solely processing motion information but further research has shown that it is also involved in various different cognitive operations, such as working memory tasks requiring motion-related information to be maintained or cognitive tasks with implied or expected motion.In the present fMRI study in humans, we focused on MT+ modulation during working memory maintenance using a dynamic shape-tracking working memory task with no motion-related working memory content. Working memory load was systematically varied using complex and simple stimulus material and parametrically increasing retention periods. Activation patterns for the difference between retention of complex and simple memorized stimuli were examined in order to preclude that the reported effects are caused by differences in retrieval. Conjunction analysis over all delay durations for the maintenance of complex versus simple stimuli demonstrated a wide-spread activation pattern. Percent signal change (PSC) in area MT+ revealed a pattern with higher values for the maintenance of complex shapes compared to the retention of a simple circle and with higher values for increasing delay durations. The present data extend previous knowledge by demonstrating that visual area MT+ presents a brain activity pattern usually found in brain regions that are actively involved in working memory maintenance.

  2. Endonuclease α from Saccharomyces cerevisiae shows increased activity on ultraviolet irradiated native DNA

    International Nuclear Information System (INIS)

    Bryant, D.W.; Haynes, R.H.

    1978-01-01

    Endonuclease α isolated from the nucleus of the yeast Saccharomyces cerevisiae is a DNA endonuclease which has been shown to act preferentially on denatured T7 DNA. The purified enzyme is more active with UV-irradiated native T7 DNA than with unirradiated substrate. The relation between damage, measured by pyrimidine dimer concentration, and excess endonuclease activity is most readily explained by local denaturation caused by the presence of pyrimidine dimers. When three radiation sensitive mutants of yeast were tested for the level of endonuclease α present, none were found lacking the enzyme. However, nuclei of strain rad 1-1, a mutant that may be defective in heteroduplex repair as well as excision repair, were found to contain reduced levels of the endonuclease. (orig./AJ) [de

  3. Silver Nanoparticles Synthesized Using Wild Mushroom Show Potential Antimicrobial Activities against Food Borne Pathogens

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    Yugal Kishore Mohanta

    2018-03-01

    Full Text Available The present study demonstrates an economical and eco-friendly method for the synthesis of silver nanoparticles (AgNPs using the wild mushroom Ganoderma sessiliforme. The synthesis of AgNPs was confirmed and the products characterized by UV-visible spectroscopy, dynamic light scattering spectroscopy and X-ray diffraction analysis. Furthermore, Fourier transform infrared spectroscopy (ATR-FTIR analysis was performed to identify the viable biomolecules involved in the capping and active stabilization of AgNPs. Moreover, the average sizes and morphologies of AgNPs were analyzed by field emission scanning electron microscopy (FE-SEM. The potential impacts of AgNPs on food safety and control were evaluated by the antimicrobial activity of the synthesized AgNPs against common food-borne bacteria, namely, Escherichia coli, Bacillus subtilis, Streptococcus faecalis, Listeria innocua and Micrococcus luteus. The results of this study revealed that the synthesized AgNPs can be used to control the growth of food-borne pathogens and have potential application in the food packaging industry. Moreover, the AgNPs were evaluated for antioxidant activity (DPPH, for biocompatibility (L-929, normal fibroblast cells, and for cytotoxic effects on human breast adenosarcoma cells (MCF-7 & MDA-MB231 to highlight their potential for use in a variety of bio-applications.

  4. A novel class of thiosemicarbazones show multi-functional activity for the treatment of Alzheimer's disease.

    Science.gov (United States)

    Palanimuthu, Duraippandi; Poon, Rachal; Sahni, Sumit; Anjum, Rukhsana; Hibbs, David; Lin, Hsuan-Yu; Bernhardt, Paul V; Kalinowski, Danuta S; Richardson, Des R

    2017-10-20

    Over 44 million people live with Alzheimer's disease (AD) worldwide. Currently, only symptomatic treatments are available for AD and no cure exists. Considering the lack of effective treatments for AD due to its multi-factorial pathology, development of novel multi-target-directed drugs are desirable. Herein, we report the development of a novel series of thiosemicarbazones derived from 1-benzylpiperidine, a pharmacophore within the acetylcholinesterase inhibitor, Donepezil. These thiosemicarbazones were designed to target five major AD hallmarks, including: low acetylcholine levels, dysfunctional autophagy, metal dys-homeostasis, protein aggregation and oxidative stress. Of these thiosemicarbazones, pyridoxal 4-N-(1-benzylpiperidin-4-yl)thiosemicarbazone (PBPT) emerged as the lead compound. This agent demonstrated the most promising multi-functional activity by exhibiting very low anti-proliferative activity, substantial iron chelation efficacy, inhibition of copper-mediated amyloid-β aggregation, inhibition of oxidative stress, moderate acetylcholinesterase inhibitory activity and autophagic induction. These diverse properties highlight the potential of the lead ligand, PBPT, as a promising multi-functional agent for AD treatment. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. Glycophenotype Evaluation in Cutaneous Tumors Using Lectins Labeled with Acridinium Ester

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    Luiza Rayanna Amorim Lima

    2013-01-01

    Full Text Available Background. Tumor cells show alterations in their glycosylation patterns when compared to normal cells. Lectins can be used to evaluate these glycocode changes. Chemiluminescence assay is an effective technique for quantitative analysis of proteins, nucleic acids, and carbohydrates due to its high sensitivity, specificity, and rapid testing. Objective. To use histochemiluminescence based on lectin conjugated to acridinium ester (AE for the investigation of glycophenotype changes in cutaneous tumors. Methods. Concanavalin A (Con A, Peanut agglutinin (PNA, Ulex europaeus agglutinin-I (UEA-I, and Maackia amurensis agglutinin (MAA were conjugated to acridinium ester. Biopsies of cutaneous tumors and normal skin were incubated with the lectins-AE, and chemiluminescence was quantified and expressed as Relative Light Units (RLU. Results. Actinic keratosis (AK, keratoacanthoma (KA, squamous cell carcinoma (SCC, and basal cell carcinoma (BCC showed lower expression of α-D-glucose/mannose and α-L-fucose residues compared to normal tissue. Cutaneous tumors displayed higher expression of Gal-β(1-3-GalNAc residues than normal tissue. AK and SCC exhibited higher expression of Neu5Ac-α(2,3Gal residues than normal epidermis. KA and BCC showed equivalent RLU values compared to normal tissue. Conclusions. Lectin histochemiluminescence allowed quantitative assessment of the carbohydrate expression in cutaneous tissues, contributing to eliminate the subjectivity of conventional techniques used in the histopathological diagnosis.

  6. Glycophenotype evaluation in cutaneous tumors using lectins labeled with acridinium ester.

    Science.gov (United States)

    Lima, Luiza Rayanna Amorim; Bezerra, Matheus Filgueira; Almeida, Sinara Mônica Vitalino; Silva, Lúcia Patrícia Bezerra Gomes; Beltrão, Eduardo Isidoro Carneiro; Carvalho Júnior, Luiz Bezerra

    2013-01-01

    Tumor cells show alterations in their glycosylation patterns when compared to normal cells. Lectins can be used to evaluate these glycocode changes. Chemiluminescence assay is an effective technique for quantitative analysis of proteins, nucleic acids, and carbohydrates due to its high sensitivity, specificity, and rapid testing. To use histochemiluminescence based on lectin conjugated to acridinium ester (AE) for the investigation of glycophenotype changes in cutaneous tumors. Concanavalin A (Con A), Peanut agglutinin (PNA), Ulex europaeus agglutinin-I (UEA-I), and Maackia amurensis agglutinin (MAA) were conjugated to acridinium ester. Biopsies of cutaneous tumors and normal skin were incubated with the lectins-AE, and chemiluminescence was quantified and expressed as Relative Light Units (RLU). Results. Actinic keratosis (AK), keratoacanthoma (KA), squamous cell carcinoma (SCC), and basal cell carcinoma (BCC) showed lower expression of α -D-glucose/mannose and α -L-fucose residues compared to normal tissue. Cutaneous tumors displayed higher expression of Gal- β (1-3)-GalNAc residues than normal tissue. AK and SCC exhibited higher expression of Neu5Ac- α (2,3)Gal residues than normal epidermis. KA and BCC showed equivalent RLU values compared to normal tissue. Lectin histochemiluminescence allowed quantitative assessment of the carbohydrate expression in cutaneous tissues, contributing to eliminate the subjectivity of conventional techniques used in the histopathological diagnosis.

  7. Arabidopsis Lectin Receptor Kinases LecRK-IX.1 and LecRK-IX.2 Are Functional Analogs in Regulating Phytophthora Resistance and Plant Cell Death.

    Science.gov (United States)

    Wang, Yan; Cordewener, Jan H G; America, Antoine H P; Shan, Weixing; Bouwmeester, Klaas; Govers, Francine

    2015-09-01

    L-type lectin receptor kinases (LecRK) are potential immune receptors. Here, we characterized two closely-related Arabidopsis LecRK, LecRK-IX.1 and LecRK-IX.2, of which T-DNA insertion mutants showed compromised resistance to Phytophthora brassicae and Phytophthora capsici, with double mutants showing additive susceptibility. Overexpression of LecRK-IX.1 or LecRK-IX.2 in Arabidopsis and transient expression in Nicotiana benthamiana increased Phytophthora resistance but also induced cell death. Phytophthora resistance required both the lectin domain and kinase activity, but for cell death, the lectin domain was not needed. Silencing of the two closely related mitogen-activated protein kinase genes NbSIPK and NbNTF4 in N. benthamiana completely abolished LecRK-IX.1-induced cell death but not Phytophthora resistance. Liquid chromatography-mass spectrometry analysis of protein complexes coimmunoprecipitated in planta with LecRK-IX.1 or LecRK-IX.2 as bait, resulted in the identification of the N. benthamiana ABC transporter NbPDR1 as a potential interactor of both LecRK. The closest homolog of NbPDR1 in Arabidopsis is ABCG40, and coimmunoprecipitation experiments showed that ABCG40 associates with LecRK-IX.1 and LecRK-IX.2 in planta. Similar to the LecRK mutants, ABCG40 mutants showed compromised Phytophthora resistance. This study shows that LecRK-IX.1 and LecRK-IX.2 are Phytophthora resistance components that function independent of each other and independent of the cell-death phenotype. They both interact with the same ABC transporter, suggesting that they exploit similar signal transduction pathways.

  8. Use of lectin-functionalized particles for oral immunotherapy

    Science.gov (United States)

    Diesner, Susanne C; Wang, Xue-Yan; Jensen-Jarolim, Erika; Untersmayr, Eva; Gabor, Franz

    2013-01-01

    Immunotherapy, in recent times, has found its application in a variety of immunologically mediated diseases. Oral immunotherapy may not only increase patient compliance but may, in particular, also induce both systemic as well as mucosal immune responses, due to mucosal application of active agents. To improve the bioavailability and to trigger strong immunological responses, recent research projects focused on the encapsulation of drugs and antigens into polymer particles. These particles protect the loaded antigen from the harsh conditions in the GI tract. Furthermore, modification of the surface of particles by the use of lectins, such as Aleuria aurantia lectin, wheatgerm agglutinin or Ulex europaeus-I, enhances the binding to epithelial cells, in particular to membranous cells, of the mucosa-associated lymphoid tissue. Membranous cell-specific targeting leads to an improved transepithelial transport of the particle carriers. Thus, enhanced uptake and presentation of the encapsulated antigen by antigen-presenting cells favor strong systemic, but also local, mucosal immune responses. PMID:22834202

  9. Anti-Neuroblastoma Properties of a Recombinant Sunflower Lectin

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    Marcela Pinedo

    2017-01-01

    Full Text Available According to their sugar recognition specificity, plant lectins are proposed as bioactive proteins with potential in cancer treatment and diagnosis. Helja is a mannose-specific jacalin-like lectin from sunflower which was shown to inhibit the growth of certain fungi. Here, we report its recombinant expression in a prokaryotic system and its activity in neurobalstoma cells. Helja coding sequence was fused to the pET-32 EK/LIC, the enterokinase/Ligation-independent cloning vector and a 35 kDa protein was obtained in Escherichia coli representing Helja coupled to thioredoxin (Trx. The identity of this protein was verified using anti-Helja antibodies. This chimera, named Trx-rHelja, was enriched in the soluble bacterial extracts and was purified using Ni+2-Sepharose and d-mannose-agarose chromatography. Trx-rHelja and the enterokinase-released recombinant Helja (rHelja both displayed toxicity on human SH-SY5Y neuroblastomas. rHelja decreased the viability of these tumor cells by 75% according to the tetrazolium reduction assay, and microscopic analyses revealed that the cell morphology was disturbed. Thus, the stellate cells of the monolayer became spheroids and were isolated. Our results indicate that rHelja is a promising tool for the development of diagnostic or therapeutic methods for neuroblastoma cells, the most common solid tumors in childhood.

  10. Functional coupling networks inferred from prefrontal cortex activity show experience-related effective plasticity

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    Gaia Tavoni

    2017-10-01

    Full Text Available Functional coupling networks are widely used to characterize collective patterns of activity in neural populations. Here, we ask whether functional couplings reflect the subtle changes, such as in physiological interactions, believed to take place during learning. We infer functional network models reproducing the spiking activity of simultaneously recorded neurons in prefrontal cortex (PFC of rats, during the performance of a cross-modal rule shift task (task epoch, and during preceding and following sleep epochs. A large-scale study of the 96 recorded sessions allows us to detect, in about 20% of sessions, effective plasticity between the sleep epochs. These coupling modifications are correlated with the coupling values in the task epoch, and are supported by a small subset of the recorded neurons, which we identify by means of an automatized procedure. These potentiated groups increase their coativation frequency in the spiking data between the two sleep epochs, and, hence, participate to putative experience-related cell assemblies. Study of the reactivation dynamics of the potentiated groups suggests a possible connection with behavioral learning. Reactivation is largely driven by hippocampal ripple events when the rule is not yet learned, and may be much more autonomous, and presumably sustained by the potentiated PFC network, when learning is consolidated. Cell assemblies coding for memories are widely believed to emerge through synaptic modification resulting from learning, yet their identification from activity is very arduous. We propose a functional-connectivity-based approach to identify experience-related cell assemblies from multielectrode recordings in vivo, and apply it to the prefrontal cortex activity of rats recorded during a task epoch and the preceding and following sleep epochs. We infer functional couplings between the recorded cells in each epoch. Comparisons of the functional coupling networks across the epochs allow us

  11. Retinoblastoma pathway defects show differential ability to activate the constitutive DNA damage response in human tumorigenesis

    DEFF Research Database (Denmark)

    Tort, F.; Bartkova, J.; Sehested, M.

    2006-01-01

    culture models with differential defects of retinoblastoma pathway components, as overexpression of cyclin D1 or lack of p16(Ink4a), either alone or combined, did not elicit detectable DDR. In contrast, inactivation of pRb, the key component of the pathway, activated the DDR in cultured human or mouse...... with their hierarchical positions along the retinoblastoma pathway. Our data provide new insights into oncogene-evoked DDR in human tumorigenesis, with potential implications for individualized management of tumors with elevated cyclin D1 versus cyclin E, due to their distinct clinical variables and biological behavior....

  12. Cloned Bacillus subtilis alkaline protease (aprA) gene showing high level of keratinolytic activity.

    Science.gov (United States)

    Zaghloul, T I

    1998-01-01

    The Bacillus subtilis alkaline protease(aprA) gene was previously cloned on a pUBHO-derivative plasmid. High levels of expression and gene stability were demonstrated when B. subtilis cells were grown on the laboratory medium 2XSG. B. subtilis cells harboring the multicopy aprA gene were grown on basal medium, supplemented with 1 % chicken feather as a source of energy, carbon, and nitrogen. Proteolytic and keratinolytic activities were monitored throughout the cultivation time. A high level of keratinolytic activity was obtained, and this indicates that alkaline protease is acting as a keratinase. Furthermore, considerable amounts of soluble proteins and free amino acids were obtained as a result of the enzymatic hydrolysis of feather. Biodegradation of feather waste using these cells represents an alternative way to improve the nutritional value of feather, since feather waste is currently utilized on a limited basis as a dietary protein supplement for animal feedstuffs. Moreover, the release of free amino acids from feather and the secreted keratinase enzyme would promote industries based on feather waste.

  13. Alcoholic Extract of Eclipta alba Shows In Vitro Antioxidant and Anticancer Activity without Exhibiting Toxicological Effects

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    Navneet Kumar Yadav

    2017-01-01

    Full Text Available As per WHO estimates, 80% of people around the world use medicinal plants for the cure and prevention of various diseases including cancer owing to their easy availability and cost effectiveness. Eclipta alba has long been used in Ayurveda to treat liver diseases, eye ailments, and hair related disorders. The promising medicinal value of E. alba prompted us to study the antioxidant, nontoxic, and anticancer potential of its alcoholic extract. In the current study, we evaluated the in vitro cytotoxic and antioxidant effect of the alcoholic extract of Eclipta alba (AEEA in multiple cancer cell lines along with control. We have also evaluated its effect on different in vivo toxicity parameters. Here, we found that AEEA was found to be most active in most of the cancer cell lines but it significantly induced apoptosis in human breast cancer cell lines by disrupting mitochondrial membrane potential and DNA damage. Moreover, AEEA treatment inhibited migration in both MCF 7 and MDA-MB-231 cells in a dose dependent manner. Further, AEEA possesses robust in vitro antioxidant activity along with high total phenolic and flavonoid contents. In summary, our results indicate that Eclipta alba has enormous potential in complementary and alternative medicine for the treatment of cancer.

  14. Potential Antioxidant Anthraquinones Isolated from Rheum emodi Showing Nematicidal Activity against Meloidogyne incognita

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    Brijesh Tripathi

    2014-01-01

    Full Text Available Antioxidant and nematicidal properties were evaluated for R. emodi extractives which are extracted by standardizing and adopting accelerated solvent extraction (ASE method along with traditional Soxhlet extraction. The extracted material was separated using flash chromatography and the separation conditions and solvents were standardized for the extracted plant constituents. The purity was detected by using analytical reverse phase high pressure liquid chromatography (HPLC. LC-MS/MS detection in the direct infusion mode of the isolated, purified products afforded four anthraquinones, characterized by their infrared spectra (IR and 1H spectra as chrysophanol, physcion, emodin, and aloe-emodin. Five antraquinone glucoside derivatives and piceatannol-3-O-β-d-glucopyranoside have also been detected from the extracted product. During in vitro evaluation the antioxidant potential of methanolic crude extract (CE1 was the highest, followed by ethyl acetate crude extract (CE2 and chloroform extract (CE3 in DPPH radical scavenging activity. The CE1 also demonstrated outstanding nematicidal activity as compared with other extracts, pure anthraquinones, and even positive control azadirachtin. The study conclusively demonstrated the antioxidant potential of R. emodi extracts and also its ability in extenuating the Meloidogyne incognita (root-knot nematode. The bioassay results can be extrapolated to actual field condition and clinical studies.

  15. Medicinal plants and their isolated compounds showing anti-Trichomonas vaginalis- activity.

    Science.gov (United States)

    Mehriardestani, Mozhgan; Aliahmadi, Atousa; Toliat, Tayebeh; Rahimi, Roja

    2017-04-01

    Trichomonas vaginalis is a major of non-viral sexually-transmitted infection and an important cause of serious obstetrical and gynecological complications. Treatment options for trichomoniasis are limited to nitroimidazole compounds. The increasing resistance and allergic reactions to nitroimidazole and recurrent trichomoniasis make it essential to identify and develop new drugs against trichomoniasis. Medicinal plants are an important source for discovery of new medications. This review discusses the anti-trichomonas effects of medicinal plants and their chemical constituents to find better options against this pathogenic protozoon. Electronic databases were searched to collect all data from the year 2000 through September 2015 for in vitro, in vivo and clinical studies on the effect of medicinal plants on T. vaginalis. A total of 95 in vitro and clinical studies were identified. Only four human studies were found in this review. The Asteracea, Lamiaceae and Myrtaceae families contained the greatest number of plants with anti-trichomonas activity. Persea americana, Ocimum basilicum and Verbascum thapsus were the most efficacious against T. vaginalis. Plant metabolites containing alkaloids, isoflavonoid glucosides, essential oils, lipids, saponins and sesquiterpene lactones were found to possess anti-trichomonas properties. Assessing the structure-activity of highly-potent anti-trichomonas phytochemicals is suggested for finding natural, semisynthetic and synthetic anti-trichomonas compounds. Further clinical studies are necessary for confirmation of natural anti-trichomonas substances and completion of their safety profiles. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  16. A new method of lectin histochemistry for the study of brain angiogenesis. Lectin angiography.

    Science.gov (United States)

    Minamikawa, T; Miyake, T; Takamatsu, T; Fujita, S

    1987-01-01

    In an attempt to analyse the kinetics of angiogenesis in the brain, we developed a new lectin-histochemical staining technique for identifying the vasculature. Three horseradish-peroxidase-conjugated lectins, i.e., Griffonia simplicifolia agglutinin 1 (GS1), Ricinus communis agglutinin 1 (RCA1) and soybean agglutinin (SBA), selectively stained vascular walls in brain-tissue sections. When these lectins were injected into the circulation of ether-anesthetized animals via the pulsating left ventricle, they bound specifically to the inner surface of endothelial cells and revealed the three-dimensional architecture of the vascular network within thick tissue preparations. When this technique, referred to a lectin angiography, was combined with 5-bromo-2-deoxyuridine (BudR) immunohistochemistry, proliferating capillary cells could be easily identified in three-dimensional structures of the developing vasculature. Because of its simplicity and wide applicability, lectin angiography should be useful for analysing the kinetics of angiogenesis in developmental, regenerative, and pathological conditions in various tissues and organs.

  17. Genetically engineered fusion of MAP-1 and factor H domains 1-5 generates a potent dual upstream inhibitor of both the lectin and alternative complement pathways

    DEFF Research Database (Denmark)

    Nordmaj, Mie Anemone; Munthe-Fog, Lea; Hein, Estrid

    2015-01-01

    Inhibition of the complement cascade has emerged as an option for treatment of a range of diseases. Mannose-binding lectin/ficolin/collectin-associated protein (MAP-1) is a pattern recognition molecule (PRM)-associated inhibitor of the lectin pathway. The central regulator of the alternative......:4 in a solid-phase functional assay, only the first 5 N-terminal domains of complement FH fused to the C-terminal part of full-length MAP-1 chimeric construct were able to combine inhibition of lectin and AP activation with an half maximal inhibitory concentration of ∼ 100 and 20 nM, respectively. No effect...

  18. PVP-coated silver nanoparticles showing antifungal improved activity against dermatophytes

    Science.gov (United States)

    Silva, Edgar; Saraiva, Sofia M.; Miguel, Sónia P.; Correia, Ilídio J.

    2014-11-01

    Fungal infections affecting human beings have increased during the last years and the currently available treatments, when administered for long periods, trigger microbial resistance. Such demands the development of new viable therapeutic alternatives. Silver is known since the antiquity by its antimicrobial properties and, herein, it was used to produce two types of nanoparticles (NPs), uncoated and coated with polyvinylpyrrolidone (PVP), which were aimed to be used in fungal infection treatment. NPs properties were characterized by Transmission electron microscopy, X-ray diffraction, UV-Vis, Dynamic light scattering, Fourier transform infrared, and Energy-dispersive X-ray spectroscopy. Furthermore, in vitro studies were also performed to evaluate NPs cytotoxic profile and antifungal activity. The results obtained revealed that the produced nanoparticles are biocompatible and have a good potential for being used in the treatment of common skin infections caused by Trichophyton rubrum and Trichophyton mentagrophytes, being PVP-coated silver NPs the most suitable ones.

  19. The combination of sorafenib and everolimus shows antitumor activity in preclinical models of malignant pleural mesothelioma

    International Nuclear Information System (INIS)

    Pignochino, Ymera; Dell’Aglio, Carmine; Inghilleri, Simona; Zorzetto, Michele; Basiricò, Marco; Capozzi, Federica; Canta, Marta; Piloni, Davide; Cemmi, Francesca; Sangiolo, Dario; Gammaitoni, Loretta; Soster, Marco; Marchiò, Serena; Pozzi, Ernesto; Morbini, Patrizia; Luisetti, Maurizio; Aglietta, Massimo; Grignani, Giovanni; Stella, Giulia M

    2015-01-01

    Malignant Pleural Mesothelioma (MPM) is an aggressive tumor arising from mesothelial cells lining the pleural cavities characterized by resistance to standard therapies. Most of the molecular steps responsible for pleural transformation remain unclear; however, several growth factor signaling cascades are known to be altered during MPM onset and progression. Transducers of these pathways, such as PIK3CA-mTOR-AKT, MAPK, and ezrin/radixin/moesin (ERM) could therefore be exploited as possible targets for pharmacological intervention. This study aimed to identify ‘druggable’ pathways in MPM and to formulate a targeted approach based on the use of commercially available molecules, such as the multikinase inhibitor sorafenib and the mTOR inhibitor everolimus. We planned a triple approach based on: i) analysis of immunophenotypes and mutational profiles in a cohort of thoracoscopic MPM samples, ii) in vitro pharmacological assays, ii) in vivo therapeutic approaches on MPM xenografts. No mutations were found in ‘hot spot’ regions of the mTOR upstream genes (e.g. EGFR, KRAS and PIK3CA). Phosphorylated mTOR and ERM were specifically overexpressed in the analyzed MPM samples. Sorafenib and everolimus combination was effective in mTOR and ERM blockade; exerted synergistic effects on the inhibition of MPM cell proliferation; triggered ROS production and consequent AMPK-p38 mediated-apoptosis. The antitumor activity was displayed when orally administered to MPM-bearing NOD/SCID mice. ERM and mTOR pathways are activated in MPM and ‘druggable’ by a combination of sorafenib and everolimus. Combination therapy is a promising therapeutic strategy against MPM. The online version of this article (doi:10.1186/s12885-015-1363-1) contains supplementary material, which is available to authorized users

  20. Novel mesostructured inclusions in the epidermal lining of Artemia franciscana ovisacs show optical activity

    Directory of Open Access Journals (Sweden)

    Elena Hollergschwandtner

    2017-10-01

    Full Text Available Background Biomineralization, e.g., in sea urchins or mollusks, includes the assembly of mesoscopic superstructures from inorganic crystalline components and biopolymers. The resulting mesocrystals inspire biophysicists and material scientists alike, because of their extraordinary physical properties. Current efforts to replicate mesocrystal synthesis in vitro require understanding the principles of their self-assembly in vivo. One question, not addressed so far, is whether intracellular crystals of proteins can assemble with biopolymers into functional mesocrystal-like structures. During our electron microscopy studies into Artemia franciscana (Crustacea: Branchiopoda, we found initial evidence of such proteinaceous mesostructures. Results EM preparations with high-pressure freezing and accelerated freeze substitution revealed an extraordinary intracellular source of mesostructured inclusions in both the cyto-and nucleoplasm of the epidermal lining of ovisacs of A. franciscana. Confocal reflection microscopy not only confirmed our finding; it also revealed reflective, light dispersing activity of these flake-like structures, their positioning and orientation with respect to the ovisac inside. Both the striation of alternating electron dense and electron-lucent components and the sharp edges of the flakes indicate self-assembly of material of yet unknown origin under supposed participation of crystallization. However, selected area electron diffraction could not verify the status of crystallization. Energy dispersive X-ray analysis measured a marked increase in nitrogen within the flake-like inclusion, and the almost complete absence of elements that are typically involved in inorganic crystallization. This rise in nitrogen could possibility be related to higher package density of proteins, achieved by mesostructure assembly. Conclusions The ovisac lining of A. franciscana is endowed with numerous mesostructured inclusions that have not been

  1. Mucosal immunogenicity of plant lectins in mice

    Science.gov (United States)

    Lavelle, E C; Grant, G; Pusztai, A; Pfüller, U; O’Hagan, D T

    2000-01-01

    The mucosal immunogenicity of a number of plant lectins with different sugar specificities was investigated in mice. Following intranasal (i.n.) or oral administration, the systemic and mucosal antibody responses elicited were compared with those induced by a potent mucosal immunogen (cholera toxin; CT) and a poorly immunogenic protein (ovalbumin; OVA). After three oral or i.n. doses of CT, high levels of specific serum antibodies were measured and specific IgA was detected in the serum, saliva, vaginal wash, nasal wash and gut wash of mice. Immunization with OVA elicited low titres of serum IgG but specific IgA was not detected in mucosal secretions. Both oral and i.n. delivery of all five plant lectins investigated [Viscum album (mistletoe lectin 1; ML‐1), Lycospersicum esculentum (tomato lectin; LEA), Phaseolus vulgaris (PHA), Triticum vulgaris (wheat germ agglutinin (WGA), Ulex europaeus I (UEA‐1)] stimulated the production of specific serum IgG and IgA antibody after three i.n. or oral doses. Immunization with ML‐1 induced high titres of serum IgG and IgA in addition to specific IgA in mucosal secretions. The response to orally delivered ML‐1 was comparable to that induced by CT, although a 10‐fold higher dose was administered. Immunization with LEA also induced high titres of serum IgG, particularly after i.n. delivery. Low specific IgA titres were also detected to LEA in mucosal secretions. Responses to PHA, WGA and UEA‐1 were measured at a relatively low level in the serum, and little or no specific mucosal IgA was detected. PMID:10651938

  2. Production of polyclonal antibodies for lectin from Anticarsia gemmatalis hemolymph Produção de anticorpos policlonais para lectina de hemolinfa de Anticarsia gemmatalis

    Directory of Open Access Journals (Sweden)

    Mario Augusto Ono

    2005-10-01

    Full Text Available The velvet bean caterpillar Anticarsia gemmatalis promotes extensive damage to soybean and is controlled frequently by chemical insecticides. Due to risks to human and animal health as well as the environment, new approaches were developed to A. gemmatalis control such as the bioinsectide Baculoviru anticarsia. The development of resistance in A. gemmatalis populations treated along several generations with B. anticarsia was reported under laboratory conditions. The insects show complex mechanisms against microorganism infection, such as the lectins, that work as recognition molecules. The aim of this work was to develop polyclonal antibodies to A. gemmatalis lectin. The lectin activity in A. gemmatalis caterpillar hemolymph was evaluated using erythrocytes from human, rabbit, mouse, sheep and cow. Only bovine erythrocytes were not agglutinated by lectin. The rabbit erythrocytes showed stronger reactivity (1:512. Therefore the polyclonal antibodies were raised in rabbit immunized with autologous erythrocytes sensitized with lectin. The antibody to lectin showed a titer of 1:8 in immunodiffusion test. In this study we described a simple method for antibody production against hemolymph lectin without expensive purification techniques. A lagarta de Anticarsia gemmatalis promove extensos danos na cultura da soja e seu controle é geralmente baseado na aplicação de inseticidas químicos. Devido aos riscos à saúde humana, animal e ao meio ambiente, métodos alternativos de controle tem sido desenvolvidos como o bioinseticida Baculovirus anticarsia. Há relatos de desenvolvimento de resistência em populações de A. gemmatalis submetidas, em laboratório, ao tratamento com baculovirus durante várias gerações. Os insetos apresentam mecanismos elaborados de proteção contra agentes infecciosos, como as lectinas, que atuam como moléculas de reconhecimento. Assim, o objetivo deste estudo foi desenvolver anticorpos policlonais para lectina de A

  3. Lectins discriminate between pathogenic and nonpathogenic South American trypanosomes

    International Nuclear Information System (INIS)

    de Miranda Santos, I.K.; Pereira, M.E.

    1984-01-01

    Cell surface carbohydrates of Trypanosoma cruzi, Trypanosoma rangeli, and Trypanosoma conorhini were analyzed by a micro-agglutination assay employing 27 highly purified lectins and by binding assays using various 125 I-labeled lectins. The following seven lectins discriminated between the trypanosomes: 1) tomato lectin (an N-acetyl-D-glucosamine-binding protein), both in purified form and as crude tomato juice; 2) Bauhinea purpurea and Sophora japonica lectins (both N-acetyl-D-galactosamine-binding proteins), which selectively agglutinated T. cruzi; 3) Vicia villosa (an N-acetyl-D-galactosamine-binding protein) which was specific for T. rangeli; 4) peanut lectin (a D-galactose-binding protein) both in purified form and as crude saline extract; and 5) Ulex europaeus and Lotus tetragonolobus (both L-fucose-binding proteins) lectins which reacted only with T. conorhini. Binding studies with 125I-labeled lectins were performed to find whether unagglutinated cells of the three different species of trypanosomes might have receptors for these lectins, in which case absence of agglutination could be due to a peculiar arrangement of the receptors. These assays essentially confirmed the agglutination experiments

  4. Lectins discriminate between pathogenic and nonpathogenic South American trypanosomes

    Energy Technology Data Exchange (ETDEWEB)

    de Miranda Santos, I.K.; Pereira, M.E.

    1984-09-01

    Cell surface carbohydrates of Trypanosoma cruzi, Trypanosoma rangeli, and Trypanosoma conorhini were analyzed by a micro-agglutination assay employing 27 highly purified lectins and by binding assays using various /sup 125/I-labeled lectins. The following seven lectins discriminated between the trypanosomes: 1) tomato lectin (an N-acetyl-D-glucosamine-binding protein), both in purified form and as crude tomato juice; 2) Bauhinea purpurea and Sophora japonica lectins (both N-acetyl-D-galactosamine-binding proteins), which selectively agglutinated T. cruzi; 3) Vicia villosa (an N-acetyl-D-galactosamine-binding protein) which was specific for T. rangeli; 4) peanut lectin (a D-galactose-binding protein) both in purified form and as crude saline extract; and 5) Ulex europaeus and Lotus tetragonolobus (both L-fucose-binding proteins) lectins which reacted only with T. conorhini. Binding studies with 125I-labeled lectins were performed to find whether unagglutinated cells of the three different species of trypanosomes might have receptors for these lectins, in which case absence of agglutination could be due to a peculiar arrangement of the receptors. These assays essentially confirmed the agglutination experiments.

  5. Crystal Structure and Functional Characterization of the Complement Regulator Mannose-binding Lectin (MBL)/Ficolin-associated Protein-1 (MAP-1)

    DEFF Research Database (Denmark)

    Skjoedt, M.-o.; Roversi, P.; Hummelshoj, T.

    2012-01-01

    .5 nM, respectively. We studied structural aspects of MAP-1 and could show by multi-angle laser light scattering that MAP-1 forms a calcium-dependent homo-dimer in solution. We were able to determine the crystal structure of MAP-1, which also contains a head-to-tail dimer approximately 146 Angstrom...... long. This structure of MAP-1 also enables modeling and assembly of the MASP-1 molecule in its entirety. Finally we found that MAP-1 competes with all three MASPs for ligand binding and is able to mediate a strong dose dependent inhibitory effect on the lectin pathway activation, as measured by levels...

  6. Transmission-Blocking Antibodies against Mosquito C-Type Lectins for Dengue Prevention

    Science.gov (United States)

    Liu, Yang; Zhang, Fuchun; Liu, Jianying; Xiao, Xiaoping; Zhang, Siyin; Qin, Chengfeng; Xiang, Ye; Wang, Penghua; Cheng, Gong

    2014-01-01

    C-type lectins are a family of proteins with carbohydrate-binding activity. Several C-type lectins in mammals or arthropods are employed as receptors or attachment factors to facilitate flavivirus invasion. We previously identified a C-type lectin in Aedes aegypti, designated as mosquito galactose specific C-type lectin-1 (mosGCTL-1), facilitating the attachment of West Nile virus (WNV) on the cell membrane. Here, we first identified that 9 A. aegypti mosGCTL genes were key susceptibility factors facilitating DENV-2 infection, of which mosGCTL-3 exhibited the most significant effect. We found that mosGCTL-3 was induced in mosquito tissues with DENV-2 infection, and that the protein interacted with DENV-2 surface envelop (E) protein and virions in vitro and in vivo. In addition, the other identified mosGCTLs interacted with the DENV-2 E protein, indicating that DENV may employ multiple mosGCTLs as ligands to promote the infection of vectors. The vectorial susceptibility factors that facilitate pathogen invasion may potentially be explored as a target to disrupt the acquisition of microbes from the vertebrate host. Indeed, membrane blood feeding of antisera against mosGCTLs dramatically reduced mosquito infective ratio. Hence, the immunization against mosGCTLs is a feasible approach for preventing dengue infection. Our study provides a future avenue for developing a transmission-blocking vaccine that interrupts the life cycle of dengue virus and reduces disease burden. PMID:24550728

  7. A new mannose-specific lectin from daylily (Hemerocallis fulva L. rhizome: purification and properties

    Directory of Open Access Journals (Sweden)

    V. O. Antonyuk

    2013-04-01

    Full Text Available A new lectin was purified from the daylily (Hemerocallis fulva L. with the yield of approximately 10 mg per kg of fresh plant rhizome. The purification procedure was based on application of the affinity chromathography on the column with yeast mannan and the ion-exchange chromatography on the column with DEAE-Toyopearl. The lectin possessed low affinity for α-methyl-D-mannopyranoside, D-fructose, D-turanose and 2-acetamido-D-galactopyranose and hight affinity for the yeast mannan. The lectin bound with greatly less affinity for the mannose-containig glycoproteins, such as ovoalbumin, ovomucoid and horseradish peroxidase. According to the results of electrophoresis in 20% DSNa-PAGE, the lectin consists of subunits of 12 kDa molecular weight. According to the results of gel-chromatography on the Toyopearl HW-55, the lectin’s molecular weight is 48 kDa. It agglutinated rabbit erythrocytes very well, while rat and guinea-pig erythrocytes were agglutinated worse, and human erythrocytes were not agglutinated at all. Lectin’s dialysis against 1% EDTA or heating to 60 ºC for 60 min did not stop its hemagglutinating activity.

  8. Anti-Retroviral Lectins Have Modest Effects on Adherence of Trichomonas vaginalis to Epithelial Cells In Vitro and on Recovery of Tritrichomonas foetus in a Mouse Vaginal Model

    Science.gov (United States)

    Chatterjee, Aparajita; Ratner, Daniel M.; Ryan, Christopher M.; Johnson, Patricia J.; O’Keefe, Barry R.; Secor, W. Evan; Anderson, Deborah J.; Robbins, Phillips W.; Samuelson, John

    2015-01-01

    Trichomonas vaginalis causes vaginitis and increases the risk of HIV transmission by heterosexual sex, while Tritrichomonas foetus causes premature abortion in cattle. Our goals were to determine the effects, if any, of anti-retroviral lectins, which are designed to prevent heterosexual transmission of HIV, on adherence of Trichomonas to ectocervical cells and on Tritrichomonas infections in a mouse model. We show that Trichomonas Asn-linked glycans (N-glycans), like those of HIV, bind the mannose-binding lectin (MBL) that is part of the innate immune system. N-glycans of Trichomonas and Tritrichomonas bind anti-retroviral lectins (cyanovirin-N and griffithsin) and the 2G12 monoclonal antibody, each of which binds HIV N-glycans. Binding of cyanovirin-N appears to be independent of susceptibility to metronidazole, the major drug used to treat Trichomonas. Anti-retroviral lectins, MBL, and galectin-1 cause Trichomonas to self-aggregate and precipitate. The anti-retroviral lectins also increase adherence of ricin-resistant mutants, which are less adherent than parent cells, to ectocervical cell monolayers and to organotypic EpiVaginal tissue cells. Topical application of either anti-retroviral lectins or yeast N-glycans decreases by 40 to 70% the recovery of Tritrichomonas from the mouse vagina. These results, which are explained by a few simple models, suggest that the anti-retroviral lectins have a modest potential for preventing or treating human infections with Trichomonas. PMID:26252012

  9. Anti-Retroviral Lectins Have Modest Effects on Adherence of Trichomonas vaginalis to Epithelial Cells In Vitro and on Recovery of Tritrichomonas foetus in a Mouse Vaginal Model.

    Directory of Open Access Journals (Sweden)

    Aparajita Chatterjee

    Full Text Available Trichomonas vaginalis causes vaginitis and increases the risk of HIV transmission by heterosexual sex, while Tritrichomonas foetus causes premature abortion in cattle. Our goals were to determine the effects, if any, of anti-retroviral lectins, which are designed to prevent heterosexual transmission of HIV, on adherence of Trichomonas to ectocervical cells and on Tritrichomonas infections in a mouse model. We show that Trichomonas Asn-linked glycans (N-glycans, like those of HIV, bind the mannose-binding lectin (MBL that is part of the innate immune system. N-glycans of Trichomonas and Tritrichomonas bind anti-retroviral lectins (cyanovirin-N and griffithsin and the 2G12 monoclonal antibody, each of which binds HIV N-glycans. Binding of cyanovirin-N appears to be independent of susceptibility to metronidazole, the major drug used to treat Trichomonas. Anti-retroviral lectins, MBL, and galectin-1 cause Trichomonas to self-aggregate and precipitate. The anti-retroviral lectins also increase adherence of ricin-resistant mutants, which are less adherent than parent cells, to ectocervical cell monolayers and to organotypic EpiVaginal tissue cells. Topical application of either anti-retroviral lectins or yeast N-glycans decreases by 40 to 70% the recovery of Tritrichomonas from the mouse vagina. These results, which are explained by a few simple models, suggest that the anti-retroviral lectins have a modest potential for preventing or treating human infections with Trichomonas.

  10. Vital signs: price, activity cycle showing strong evidence of turning up again

    Energy Technology Data Exchange (ETDEWEB)

    Lunan, D.

    2002-07-01

    Economic conditions in the oil and gas industry in the first quarter of 2002 are discussed. The general conclusion is that the ride is every bit as bumpy as it was during the fourth quarter of 2001. New signs, however, point to improvement in the second half of the year, confirming predictions of recovery. The North American economy is emerging quickly from the recession, and OPEC countries seem willing to restrain production sufficiently to keep oil prices in the US$23-$25 per barrel range. As a result, North American natural gas prices will be around the US$3.00 per MMBtu level this year, benchmark West Texas Intermediate oil will average US$22.50 per barrel, up from the initial forecast of US$2.80 and US$21.50, respectively. Canadian heavy crude output in the first quarter of 2002 was down about 30,000 barrels per day from fourth quarter 2001 and about 60,000 barrel per day lower than a year ago. Natural gas prices have been firm since the New Year; Canadian natural gas storage levels stood at a record 251 billion cubic feet, while US levels stood at 1.4 trillion cubic feet, the highest since 1992, without the slightest dent in the remarkable gas price rally of February and March. Gas receipt in Western Canada at the end of March were running 508 million cubic feet per day below the July 2001 peak. No production increases for Canada are likely in 2002 in light of slower drilling activity. As far as 2003 is concerned, higher prices should encourage more drilling, but any gains will merely make up for the decline in 2002. Various methods of dealing with the problem of oxidation in transformer oil refining to minimize the risk of streaming electrification (SE) are described. Streaming electrification in transformers can lead to discharges harmful to both installations and people. The quality of transformer oil in terms of its electrostatic charging tendency (ECT) is one of several key factors affecting SE levels. Several of the factors that affect SE are directly

  11. Lectins from Synadenium carinatum (ScLL) and Artocarpus heterophyllus (ArtinM) Are Able to Induce Beneficial Immunomodulatory Effects in a Murine Model for Treatment of Toxoplasma gondii Infection.

    Science.gov (United States)

    Ramos, Eliézer L P; Santana, Silas S; Silva, Murilo V; Santiago, Fernanda M; Mineo, Tiago W P; Mineo, José R

    2016-01-01

    Infection by Toxoplasma gondii affects around one-third of world population and the treatment for patients presenting toxoplasmosis clinically manifested disease is mainly based by a combination of sulfadiazine, pyrimethamine, and folinic acid. However, this therapeutic protocol is significantly toxic, causing relevant dose-related bone marrow damage. Thus, it is necessary to improve new approaches to investigate the usefulness of more effective and non-toxic agents for treatment of patients with toxoplasmosis. It has been described that lectins from plants can control parasite infections, when used as immunological adjuvants in vaccination procedures. This type of lectins, such as ArtinM and ScLL is able to induce immunostimulatory activities, including efficient immune response against parasites. The present study aimed to evaluate the potential immunostimulatory effect of ScLL and ArtinM for treatment of T. gondii infection during acute phase, considering that there is no study in the literature accomplishing this issue. For this purpose, bone marrow-derived macrophages (BMDMs) were treated with different concentrations from each lectin to determine the maximum concentration without or with lowest cytotoxic effect. After, it was also measured the cytokine levels produced by these cells when stimulated by the selected concentrations of lectins. We found that ScLL showed high capacity to induce of pro-inflammatory cytokine production, while ArtinM was able to induce especially an anti-inflammatory cytokines production. Furthermore, both lectins were able to increase NO levels. Next, we evaluated the treatment effect of ScLL and ArtinM in C57BL/6 mice infected by ME49 strain from T. gondii . The animals were infected and treated with ScLL, ArtinM, ArtinM plus ScLL, or sulfadiazine, and the following parameters analyzed: Cytokines production, brain parasite burden and survival rates. Our results demonstrated that the ScLL or ScLL plus ArtinM treatment induced

  12. Lectins from Synadenium carinatum (ScLL and Artocarpus heterophyllus (ArtinM are able to induce beneficial immunomodulatory effects in a murine model for treatment of Toxoplasma gondii infection

    Directory of Open Access Journals (Sweden)

    Leandro Peixoto Ferreira Souza

    2016-11-01

    Full Text Available Infection by Toxoplasma gondii affects around one-third of world population and the treatment for patients presenting toxoplasmosis clinically manifested disease is mainly based by a combination of sulfadiazine, pyrimethamine and folinic acid. However, this therapeutic protocol is significantly toxic, causing relevant dose-related bone marrow damage. Thus, it is necessary to improve new approaches to investigate the usefulness of more effective and non-toxic agents for treatment of patients with toxoplasmosis. It has been described that lectins from plants can control parasite infections, when used as immunological adjuvants in vaccination procedures. This type of lectins, such as ArtinM and ScLL is able to induce immunostimulatory activities, including efficient immune response against parasites. The present study aimed to evaluate the potential immunostimulatory effect of ScLL and ArtinM for treatment of T. gondii infection during acute phase, considering that there is no study in the literature accomplishing this issue. For this purpose, bone marrow-derived macrophages (BMDMs were treated with different concentrations from each lectin to determine the maximum concentration without or with lowest cytotoxic effect. After, it was also measured the cytokine levels produced by these cells when stimulated by the selected concentrations of lectins. We found that ScLL showed high capacity to induce of pro-inflammatory cytokine production, while ArtinM was able to induce especially an anti-inflammatory cytokines production. Furthermore, both lectins were able to increase NO levels. Next, we evaluated the treatment effect of ScLL and ArtinM in C57BL/6 mice infected by ME49 strain from T. gondii. The animals were infected and treated with ScLL, ArtinM, ArtinM plus ScLL or sulfadiazine, and the following parameters analyzed: cytokines production, brain parasite burden and survival rates. Our results demonstrated that the ScLL or ScLL plus Artin

  13. Interaction of hamster submaxillary sialyl-Tn and Tn glycoproteins with Gal, GalNAc and GlcNAc specific lectins.

    Science.gov (United States)

    Wu, A M; Shen, F; Herp, A; Wu, J H

    1994-04-01

    Hamster submaxillary glycoprotein (HSM), one of the simplest glycoproteins among mammalian salivary mucins, is composed of approximately equivalent amounts of protein, hexosamine and sialic acid. The Thr and Ser residues in the protein core account for more than half of all of the amino acid residues, while Lys, Glu, Pro and Ala are the major components of the remaining portion of amino acids. The carbohydrate side chains of this mucous glycoprotein have mainly the NeuAc-GalNAc-(sialyl-Tn) sequence (HSM), and those of the desialylated product (HSM-Tn) are almost exclusively unsubstituted GalNAc residues (Tn determinants). The binding properties of sialyl-Tn (HSM) and asialo-HSM (HSM-Tn) glycoproteins were tested by precipitin assay with Gal, GalNAc and GlcNAc specific lectins. The HSM-Tn completely precipitated Vicia villosa (VVL both B4 and mixture of A and B), Maclura pomifera (MPL), and Artocarpus integrifolia (Jacalin) lectins; less than 2 micrograms of HSM-Tn were required for precipitating 50% of 5.0-6.3 micrograms lectin nitrogen added. HSM-Tn also reacted well with Helix pomatia lectin (HPL), Wistaria floribunda lectin (WFL) and Abrus precatorius agglutinin (APA) and precipitated in each case over 81% of the lectin nitrogen added. The reactivity of HSM-Tn with other lectins (Ricinus communis, RCA1; Dolichol biflorus, DBL; Viscum album, ML-I; Arachis hypogaea, PNA, and Triticum vulgaris, WGA) was weak or negligible. The activity of sialyl-Tn (HSM) was more restricted; HSM reacted well with Jacalin, moderately with MPL and VVL-B4, but was inactive or only weakly with the other lectins used. These findings indicate that HSM and its desialylated product (HSM-Tn) are highly useful reagents for the differentiation of Tn and T/Gal specific lectins and for anti-T, Tn and Af monoclonal antibodies.

  14. Immunogold study on lectin binding in the porcine zona pellucida and granulosa cells

    Directory of Open Access Journals (Sweden)

    F Parillo

    2009-06-01

    Full Text Available An ultrastructural localization of lectin receptors on the zona pellucida (ZP of porcine antral oocytes and on the granulosa cells was performed using a panel of horseradish peroxidase- labelled lectins in conjunction with antiperoxidase antibody and protein A-gold. In some cases, lectin incubation was preceded by sialidase digestion. WGA-, Con-A-, UEA-I-, RCA-I-, PNA- and SBA-reactive sites were distributed differently in the porcine ZP. Sialidase digestion increased the positivity obtained with RCA-I and it was necessary to promote PNA and SBA reactivity. These results indicated that the ZP contained N-acetylglucosamine, a-mannose, a- fucose, b-Gal-(1-4GlcNAc, b-Gal- (1-3GalNAc, b-GalNAc and sialic acid residues. We also observed the presence of vesicles in both the ooplasm and granulosa cells, showing a similar lectin binding pattern to that of the ZP, thus suggesting that the oocyte and granulosa cells are the site of synthesis of ZP glucidic determinants.

  15. Plant lectin can target receptors containing sialic acid, exemplified by podoplanin, to inhibit transformed cell growth and migration.

    Directory of Open Access Journals (Sweden)

    Jhon Alberto Ochoa-Alvarez

    Full Text Available Cancer is a leading cause of death of men and women worldwide. Tumor cell motility contributes to metastatic invasion that causes the vast majority of cancer deaths. Extracellular receptors modified by α2,3-sialic acids that promote this motility can serve as ideal chemotherapeutic targets. For example, the extracellular domain of the mucin receptor podoplanin (PDPN is highly O-glycosylated with α2,3-sialic acid linked to galactose. PDPN is activated by endogenous ligands to induce tumor cell motility and metastasis. Dietary lectins that target proteins containing α2,3-sialic acid inhibit tumor cell growth. However, anti-cancer lectins that have been examined thus far target receptors that have not been identified. We report here that a lectin from the seeds of Maackia amurensis (MASL with affinity for O-linked carbohydrate chains containing sialic acid targets PDPN to inhibit transformed cell growth and motility at nanomolar concentrations. Interestingly, the biological activity of this lectin survives gastrointestinal proteolysis and enters the cardiovascular system to inhibit melanoma cell growth, migration, and tumorigenesis. These studies demonstrate how lectins may be used to help develop dietary agents that target specific receptors to combat malignant cell growth.

  16. Extração da lectina da folha de mandioca (Manihot esculenta Crantz e o efeito de cátions divalentes na atividade hemaglutinante Extraction of the lectin of cassava leaves (Manihot esculenta Crantz and the effect of divalent cations on the hemagglutinating activity

    Directory of Open Access Journals (Sweden)

    Maria Cristina Silva

    2010-05-01

    Full Text Available Lectinas são proteínas ligantes de carboidratos, capazes de aglutinar eritrócitos, podendo exercer ação antinutricional. O isolamento destas proteínas tóxicas é interessante tanto pela sua ação antinutricional, como pela sua aplicação em biotecnologia. Algumas lectinas necessitam da presença de íons divalentes para exercer sua atividade hemaglutinante (AH. O objetivo neste trabalho foi estudar diferentes métodos de extração da lectina da farinha de folhas de mandioca (FFM e avaliar o efeito dos íons Ca2+ e Mn2+ para sua AH. Foram feitos testes de extração das proteínas utilizando dois extratores, água e solução salina (0,15 mol.L-1, pH 7,4, em quatro tempos de extração, 15, 60, 120 e 180 minutos. Para avaliar o efeito dos íons Ca2+ e Mn2+ na AH da lectina da FFM, o extrato proteico foi dialisado contra EDTA e a AH determinada. O efeito desses cátions na aglutinação de hemácias também foi avaliado isoladamente. O método de extração proteica usando água destilada como extrator por 15 minutos é o mais adequado. Não houve perda da AH na ausência dos íons. Os cátions Ca2+ (5 mmol.L-1, Mn2+ (1, 3 e 5 mmol.L-1 e a mistura de ambos nas mesmas concentrações provocam aglutinação de hemácias, na ausência de lectina.Lectins are carbohydrates binding proteins, capable of agglutinating erythrocytes, which can act as anti-nutritional factors. The isolation of these toxic proteins is interesting both for its anti- nutritional action and for its application in biotechnology. Some lectins need the presence of divalent ions to express hemagglutinating activity (AH. The objective of this work was to investigate different methods of extracting lectins from cassava leaf flour (CLF and to evaluate the effect of the ions Ca2+ and Mn2+ on the AH. Protein extraction tests were performed utilizing two extractors, water and saline solution (0.15 mol.L-1, NaCl pH 7.4, under four extraction times, 15, 60, 120, and 180 minutes

  17. MCL and mincle: C-type lectin receptors that sense damaged self and pathogen associated molecular patterns

    Directory of Open Access Journals (Sweden)

    Mark B Richardson

    2014-06-01

    Full Text Available MCL (macrophage C-type lectin and mincle (macrophage inducible C-type lectin comprise part of an extensive repertoire of pattern recognition receptors with the ability to sense damage associated and pathogen associated molecular patterns. In this review we cover the discovery and molecular characterization of these C-type lectin receptors, and highlight recent advances in the understanding of their roles in orchestrating the response of the immune system to bacterial and fungal infection, and damaged self. We also discuss the identification and structure-activity relationships of activating ligands, particularly trehalose dimycolate (TDM and related mycobacterial glycolipids, which have significant potential in the development of TH1/TH17 vaccination strategies.

  18. Lectin enhancement of the lipofection efficiency in human lung carcinoma cells.

    Science.gov (United States)

    Yanagihara, K; Cheng, P W

    1999-10-18

    Poor transfection efficiency of human lung carcinoma cells by lipofection begs further development of more efficient gene delivery strategies. The purpose of this study was to determine whether lectins can improve the lipofection efficiency in lung carcinoma cells. A549, Calu3, and H292 cells grown to 90% confluence were transfected for 18 h with a plasmid DNA containing a beta-galactosidase reporter gene (pCMVlacZ) using lipofectin plus a lectin as the vector. Ten different lectins, which exhibit a wide range of carbohydrate-binding specificities, were examined for their abilities to enhance the efficiency of lipofection. The transfected cells were assessed for transfection efficiency by beta-galactosidase activity (units/microg protein) and % blue cells following X-Gal stain. Lipofectin supplemented with Griffonia simplicifolia-I (GS-I) yields largest enhancement of the lipofection efficiency in A549 and Calu3 cells (5.3- and 28-fold, respectively). Maackia amurensis gives the largest enhancement (6.5-fold) of lipofection efficiency in H292 cells. The transfection efficiency correlates with the amounts of DNA delivered to the nucleus. Binding of FITC-labeled GS-I and the enhancement of the lipofection efficiency by GS-I were inhibited by alpha-methyl-D-galactopyranoside, indicating an alpha-galactoside-mediated gene transfer to lung carcinoma cells. We conclude that lectin-facilitated lipofection is an efficient gene delivery strategy. Employment of cell type-specific lectins may allow for efficient cell type-specific gene targeting.

  19. A simple procedure for the isolation of L-fucose-binding lectins from Ulex europaeus and Lotus tetragonolobus.

    Science.gov (United States)

    Allen, H J; Johnson, E A

    1977-10-01

    L-Fucose-binding lectins from Ulex europeaus and Lotus tetragonolobus were isolated by affinity chromatography on columns of L-fucose-Sepharose 6B. L-Fucose was coupled to Sepharose 6B after divinyl sulfone-activation of the gel to give an affinity adsorbent capable of binding more than 1.2 mg of Ulex lextin/ml of gel, which could then be eluted with 0.1M or 0.05M L-fucose. Analysis of the isolated lectins by hemagglutination assay, by gel filtration, and polyacrylamide disc-electrophoresis revealed the presence of isolectins, or aggregated species, or both. The apparent mol. wt. of the major lectin fraction from Lotus was 35000 when determined on Sephadex G-200 or Ultrogel AcA 34. In contrast, the apparent mol. wt. of the major lectin fraction from Ulex was 68 000 when chromatographed on Sephadex G-200 and 45 000 when chromatographed on Ultrogel AcA 34. The yields of lectins were 4.5 mg/100 g of Ulex seeds and 394 mg/100 g of Lotus seeds.

  20. Engineering of PA-IIL lectin from Pseudomonas aeruginosa – Unravelling the role of the specificity loop for sugar preference

    Directory of Open Access Journals (Sweden)

    Imberty Anne

    2007-06-01

    Full Text Available Abstract Background Lectins are proteins of non-immune origin capable of binding saccharide structures with high specificity and affinity. Considering the high encoding capacity of oligosaccharides, this makes lectins important for adhesion and recognition. The present study is devoted to the PA-IIL lectin from Pseudomonas aeruginosa, an opportunistic human pathogen capable of causing lethal complications in cystic fibrosis patients. The lectin may play an important role in the process of virulence, recognizing specific saccharide structures and subsequently allowing the bacteria to adhere to the host cells. It displays high values of affinity towards monosaccharides, especially fucose – a feature caused by unusual binding mode, where two calcium ions participate in the interaction with saccharide. Investigating and understanding the nature of lectin-saccharide interactions holds a great potential of use in the field of drug design, namely the targeting and delivery of active compounds to the proper site of action. Results In vitro site-directed mutagenesis of the PA-IIL lectin yielded three single point mutants that were investigated both structurally (by X-ray crystallography and functionally (by isothermal titration calorimetry. The mutated amino acids (22–23–24 triad belong to the so-called specificity binding loop responsible for the monosaccharide specificity of the lectin. The mutation of the amino acids resulted in changes to the thermodynamic behaviour of the mutants and subsequently in their relative preference towards monosaccharides. Correlation of the measured data with X-ray structures provided the molecular basis for rationalizing the affinity changes. The mutations either prevent certain interactions to be formed or allow formation of new interactions – both of afore mentioned have strong effects on the saccharide preferences. Conclusion Mutagenesis of amino acids forming the specificity binding loop allowed

  1. Current status of lectin-based cancer diagnosis and therapy

    Directory of Open Access Journals (Sweden)

    Fohona S. Coulibaly

    2017-01-01

    Full Text Available Lectins are carbohydrate recognizing proteins originating from diverse origins in nature, including animals, plants, viruses, bacteria and fungus. Due to their exceptional glycan recognition property, they have found many applications in analytical chemistry, biotechnology and surface chemistry. This manuscript explores the current use of lectins for cancer diagnosis and therapy. Moreover, novel drug delivery strategies aiming at improving lectin’s stability, reducing their undesired toxicity and controlling their non-specific binding interactions are discussed. We also explore the nanotechnology application of lectins for cancer targeting and imaging. Although many investigations are being conducted in the field of lectinology, there is still a limited clinical translation of the major findings reported due to lectins stability and toxicity concerns. Therefore, new investigations of safe and effective drug delivery system strategies for lectins are warranted in order to take full advantage of these proteins.

  2. Effects of Lectins on initial attachment of cariogenic Streptococcus mutans.

    Science.gov (United States)

    Ito, Takashi; Yoshida, Yasuhiro; Shiota, Yasuyoshi; Ito, Yuki; Yamamoto, Tadashi; Takashiba, Shogo

    2018-02-01

    Oral bacteria initiate biofilm formation by attaching to tooth surfaces via an interaction of a lectin-like bacterial protein with carbohydrate chains on the pellicle. This study aimed to find naturally derived lectins that inhibit the initial attachment of a cariogenic bacterial species, Streptococcus mutans (S. mutans), to carbohydrate chains in saliva in vitro. Seventy kinds of lectins were screened for candidate motifs that inhibit the attachment of S. mutans ATCC 25175 to a saliva-coated culture plate. The inhibitory effect of the lectins on attachment of the S. mutans to the plates was quantified by crystal violet staining, and the biofilm was observed under a scanning electron microscope (SEM). Surface plasmon resonance (SPR) analysis was performed to examine the binding of S. mutans to carbohydrate chains and the binding of candidate lectins to carbohydrate chains, respectively. Moreover, binding assay between the biotinylated-lectins and the saliva components was conducted to measure the lectin binding. Lectins recognizing a salivary carbohydrate chain, Galβ1-3GalNAc, inhibited the binding of S. mutans to the plate. In particular, Agaricus bisporus agglutinin (ABA) markedly inhibited the binding. This inhibition was confirmed by SEM observation. SPR analysis indicated that S. mutans strongly binds to Galβ1-3GalNAc, and ABA binds to Galβ1-3GalNAc. Finally, the biotinylated Galβ1-3GalNAc-binding lectins including ABA demonstrated marked binding to the saliva components. These results suggest that ABA lectin inhibited the attachment of S. mutans to Galβ1-3GalNAc in saliva and ABA can be useful as a potent inhibitor for initial attachment of oral bacteria and biofilm formation.

  3. Lectin Complement Pathway Proteins in Healthy Individuals

    DEFF Research Database (Denmark)

    Troldborg, Anne; Hansen, Annette Gudmann; Hansen, Søren W K

    2017-01-01

    , it is pivotal to know the normal. Our aim was to describe the concentrations of the eleven known proteins of the lectin pathway in serum and plasma and to uncover possible gender differences, age and diurnal variations, which must be taken into account for investigations in different cohorts. We examined...... morning to the middle of night. There were gender differences for most proteins, whereas age did not seem to influence concentration. The present study underlines the necessity of considering which material to use, correct matching and a trial design that takes the nature of the protein into account...

  4. Dynamic interplay between catalytic and lectin domains of GalNAc-transferases modulates protein O-glycosylation

    DEFF Research Database (Denmark)

    Lira-Navarrete, Erandi; de Las Rivas, Matilde; Compañón, Ismael

    2015-01-01

    the first crystal structures of complexes of GalNAc-T2 with glycopeptides that together with enhanced sampling molecular dynamics simulations demonstrate a cooperative mechanism by which the lectin domain enables free acceptor sites binding of glycopeptides into the catalytic domain. Atomic force microscopy......Protein O-glycosylation is controlled by polypeptide GalNAc-transferases (GalNAc-Ts) that uniquely feature both a catalytic and lectin domain. The underlying molecular basis of how the lectin domains of GalNAc-Ts contribute to glycopeptide specificity and catalysis remains unclear. Here we present...... and small-angle X-ray scattering experiments further reveal a dynamic conformational landscape of GalNAc-T2 and a prominent role of compact structures that are both required for efficient catalysis. Our model indicates that the activity profile of GalNAc-T2 is dictated by conformational heterogeneity...

  5. Identification of the site of human mannan-binding lectin involved in the interaction with its partner serine proteases: the essential role of Lys55

    DEFF Research Database (Denmark)

    Teillet, F; Lacroix, M; Thiel, Steffen

    2007-01-01

    Mannan-binding lectin (MBL) is an oligomeric lectin that binds neutral carbohydrates on pathogens, forms complexes with MBL-associated serine proteases (MASP)-1, -2, and -3 and 19-kDa MBL-associated protein (MAp19), and triggers the complement lectin pathway through activation of MASP-2. To ident......Mannan-binding lectin (MBL) is an oligomeric lectin that binds neutral carbohydrates on pathogens, forms complexes with MBL-associated serine proteases (MASP)-1, -2, and -3 and 19-kDa MBL-associated protein (MAp19), and triggers the complement lectin pathway through activation of MASP-2....... To identify the MASP binding site(s) of human MBL, point mutants targeting residues C-terminal to the hinge region were produced and tested for their interaction with the MASPs and MAp19 using surface plasmon resonance and functional assays. Mutation Lys(55)Ala abolished interaction with the MASPs and MAp19...... and prevented formation of functional MBL-MASP-2 complexes. Mutations Lys(55)Gln and Lys(55)Glu abolished binding to MASP-1 and -3 and strongly inhibited interaction with MAp19. Conversely, mutation Lys(55)Arg abolished interaction with MASP-2 and MAp19, but only weakened interaction with MASP-1 and -3...

  6. Lectin histochemistry as a tool to identify apoptotic cells in the seminiferous epithelium of Syrian hamster (Mesocricetus auratus) subjected to short photoperiod.

    Science.gov (United States)

    Seco-Rovira, V; Beltrán-Frutos, E; Ferrer, C; Sánchez-Huertas, M M; Madrid, J F; Saez, F J; Pastor, L M

    2013-12-01

    Lectins have been widely used to study the pattern of cellular glycoconjugates in numerous species. In the process of cellular apoptosis, it has been observed that changes occur in the membrane sugar sequences of these apoptotic cells. The aim of our work was to identify which lectins, out of an extensive battery of the same (PNA, SBA, HPA, LTA, Con-A, UEA-I, WGA, DBA, MAA, GNA, AAA, SNA), show affinity for germinal cells in apoptosis, at what stage of cell death they do so and in which germinal cell types they can be detected. For this, we studied testis sections during testicular regression in Syrian hamster (Mesocricetus auratus) subjected to short photoperiod. Several lectins showed an affinity for the glycoconjugate residues of germ cells in apoptosis: Gal β1,3-GalNAcα1, α-d-mannose, N-acetylgalactosamine and l-fucose. Furthermore, lectin specificity was observed for some specific germinal cells and in certain stages of apoptosis. It was also observed that one of these lectins (PNA) showed affinity for Sertoli cells undergoing apoptosis. Therefore, we conclude that the use of lectin histochemistry could be a very useful tool for studying apoptosis in the seminiferous epithelium because of the specificity shown towards germinal cells in pathological or experimentally induced epithelial depletion models. © 2013 Blackwell Verlag GmbH.

  7. Extrinsic functions of lectin domains in O-N-acetylgalactosamine glycan biosynthesis

    DEFF Research Database (Denmark)

    Lorenz, Virginia; Ditamo, Yanina; Cejas, Romina B

    2016-01-01

    during O-GalNAc glycan biosynthesis. The presence of lectin domain T3lec or T4lec during ppGalNAc-T2 and ppGalNAc-T3 catalytic reaction had a clear inhibitory effect on GalNAc-T activity. Interaction of T3lec or T4lec with ppGalNAc-T2 catalytic domain was not mediated by carbohydrate. T3lec, but not T2......Glycan biosynthesis occurs mainly in Golgi. Molecular organization and functional regulation of this process are not well understood. We evaluated the extrinsic effect of lectin domains (β-trefoil fold) of polypeptide GalNAc-transferases (ppGalNAc-Ts) on catalytic activity of glycosyltransferases...

  8. Characterization and optimization of ArtinM lectin expression in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Pranchevicius Maria-Cristina S

    2012-08-01

    Full Text Available Abstract Background ArtinM is a d-mannose-specific lectin from Artocarpus integrifolia seeds that induces neutrophil migration and activation, degranulation of mast cells, acceleration of wound healing, induction of interleukin-12 production by macrophages and dendritic cells, and protective T helper 1 immune response against Leishmania major, Leishmania amazonensis and Paracoccidioides brasiliensis infections. Considering the important biological properties of ArtinM and its therapeutic applicability, this study was designed to produce high-level expression of active recombinant ArtinM (rArtinM in Escherichia coli system. Results The ArtinM coding region was inserted in pET29a(+ vector and expressed in E. coli BL21(DE3-Codon Plus-RP. The conditions for overexpression of soluble ArtinM were optimized testing different parameters: temperatures (20, 25, 30 or 37°C and shaking speeds (130, 200 or 220 rpm during induction, concentrations of the induction agent IPTG (0.01-4 mM and periods of induction (1-19 h. BL21-CodonPlus(DE3-RP cells induced under the optimized conditions (incubation at 20°C, at a shaking speed of 130 rpm, induction with 0.4 mM IPTG for 19 h resulted in the accumulation of large amounts of soluble rArtinM. The culture provided 22.4 mg/L of rArtinM, which activity was determined by its one-step purification through affinity chromatography on immobilized d-mannose and glycoarray analysis. Gel filtration showed that rArtinM is monomeric, contrasting with the tetrameric form of the plant native protein (jArtinM. The analysis of intact rArtinM by mass spectrometry revealed a 16,099.5 Da molecular mass, and the peptide mass fingerprint and esi-cid-ms/ms of amino acid sequences of peptides from a tryptic digest covered 41% of the total ArtinM amino acid sequence. In addition, circular dichroism and fluorescence spectroscopy of rArtinM indicated that its global fold comprises β-sheet structure. Conclusions Overall, the

  9. Phloem-specific expression of the lectin gene from Allium sativum confers resistance to the sap-sucker Nilaparvata lugens.

    Science.gov (United States)

    Chandrasekhar, Kottakota; Vijayalakshmi, Muvva; Vani, Kalasamudramu; Kaul, Tanushri; Reddy, Malireddy K

    2014-05-01

    Rice production is severely hampered by insect pests. Garlic lectin gene (ASAL) holds great promise in conferring protection against chewing (lepidopteran) and sap-sucking (homopteran) insect pests. We have developed transgenic rice lines resistant to sap-sucking brown hopper (Nilaparvata lugens) by ectopic expression of ASAL in their phloem tissues. Molecular analyses of T0 lines confirmed stable integration of transgene. T1 lines (NP 1-2, 4-3, 11-6 & 17-7) showed active transcription and translation of ASAL transgene. ELISA revealed ASAL expression was as high as 0.95% of total soluble protein. Insect bioassays on T2 homozygous lines (NP 18 & 32) revealed significant reduction (~74-83%) in survival rate, development and fecundity of brown hoppers in comparison to wild type. Transgenics exhibited enhanced resistance (1-2 score) against brown hoppers, minimal plant damage and no growth penalty or phenotypic abnormalities.

  10. Mood Dimensions Show Distinct Within-Subject Associations With Non-exercise Activity in Adolescents: An Ambulatory Assessment Study

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    Elena D. Koch

    2018-03-01

    Full Text Available Physical activity is known to preserve both physical and mental health. However, the physical activity levels of a large proportion of adolescents are insufficient. This is critical, since physical activity levels in youth have been shown to translate into adulthood. Whereas in adult populations, mood has been supposed to be one important psychological factor that drives physical activity in everyday life, this issue has been poorly studied in adolescent populations. Ambulatory Assessment is the state-of-the-art approach to investigate how mood and non-exercise activity fluctuate within persons in everyday life. Through assessments in real time and real life, this method provides ecological validity, bypassing several limitations of traditional assessment methods (e.g., recall biases. To investigate whether mood is associated with non-exercise activity in adolescents, we equipped a community-based sample comprising 113 participants, aged 12–17 years, with GPS-triggered e-diaries querying for valence, energetic arousal, and calmness, and with accelerometers continuously measuring physical activity in their everyday lives for 1 week. We excluded all acceleration data due to participants' exercise activities and thereafter we parameterized non-exercise activity as the mean value across 10-min intervals of movement acceleration intensity following each e-diary prompt. We used multilevel analyses to compute the effects of the mood dimensions on non-exercise activity within 10-min intervals directly following each e-diary prompt. Additionally, we conducted explorative analyses of the time course of the effects, i.e., on different timeframes of non-exercise activity up to 300 min following the mood assessment. The results showed that valence (p < 0.001 and energetic arousal (p < 0.001 were positively associated with non-exercise activity within the 10 min interval, whereas calmness (p < 0.001 was negatively associated with non-exercise activity

  11. The Macrophage Galactose-Type Lectin-1 (MGL1 Recognizes Taenia crassiceps Antigens, Triggers Intracellular Signaling, and Is Critical for Resistance to This Infection

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    Daniel Montero-Barrera

    2015-01-01

    Full Text Available C-type lectins are multifunctional sugar-binding molecules expressed on dendritic cells (DCs and macrophages that internalize antigens for processing and presentation. Macrophage galactose-type lectin 1 (MGL1 recognizes glycoconjugates expressing Lewis X structures which contain galactose residues, and it is selectively expressed on immature DCs and macrophages. Helminth parasites contain large amounts of glycosylated components, which play a role in the immune regulation induced by such infections. Macrophages from MGL1−/− mice showed less binding ability toward parasite antigens than their wild-type (WT counterparts. Exposure of WT macrophages to T. crassiceps antigens triggered tyrosine phosphorylation signaling activity, which was diminished in MGL1−/− macrophages. Following T. crassiceps infection, MGL1−/− mice failed to produce significant levels of inflammatory cytokines early in the infection compared to WT mice. In contrast, MGL1−/− mice developed a Th2-dominant immune response that was associated with significantly higher parasite loads, whereas WT mice were resistant. Flow cytometry and RT-PCR analyses showed overexpression of the mannose receptors, IL-4Rα, PDL2, arginase-1, Ym1, and RELM-α on MGL1−/− macrophages. These studies indicate that MGL1 is involved in T. crassiceps recognition and subsequent innate immune activation and resistance.

  12. Morphometric Measurements to Quantify the Cerulein Induced Hyperstimulatory Pancreatitis of Rats under the Protective Effect of Lectins

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    Ludwig Jonas

    1998-01-01

    Full Text Available In preceding papers we demonstrated an inhibitory effect of wheat germ agglutinin (WGA and Ulex europaeus agglutinin (UEA on the cholecystokinin (CCK binding to the CCK receptor of rat pancreatic cells and also on the CCK induced Ca2+ release and α-amylase secretion in vitro as well as on pancreatic secretion of intact rats in vivo. In the present study we show the same inhibitory effect of both lectins on the cerulein pancreatitis of rats. This acute pancreatitis was induced by supramaximal injections (5 µg/kg/h iv or 10 µg/kg/h ip of the CCK analogue cerulein in rats every hour. To monitor the degree of pancreatitis, we measured the number and diameter of injury vacuoles in the pancreatic acinar cells as one of the most important signs of this type of pancreatitis by light microscopic morphometry with two different systems on paraffin sections. Furthermore, the serum α-amylase activity was measured biochemically. We found a correlation between the diameter of vacuoles inside the acinar cells and the serum enzyme activity up to 24 h. The simultaneous ip administration of cerulein and WGA or UEA in a dosage of 125 µg/kg/h for 8 h led to a reduction of vacuolar diameter from 13.1 ± 2.0 µm (cerulein to 7.5 ± 1.1 µm (cerulein + WGA or 7.2 ± 1.3 µm (cerulein + UEA. The serum amylase activity was reduced from 63.7 ± 15.8 mmol/l \\times min (cerulein to 37.7 ± 11.8 (cerulein + WGA or 39.4; +52.9; -31.1 (cerulein + UEA-I. Both parameters allow the grading this special type of pancreatitis to demonstrate the protective effect of the lectins.

  13. Genome sequence of Lactobacillus salivarius SMXD51, a potential probiotic strain isolated from chicken cecum, showing anti-campylobacter activity.

    Science.gov (United States)

    Kergourlay, Gilles; Messaoudi, Soumaya; Dousset, Xavier; Prévost, Hervé

    2012-06-01

    We report the draft genome sequence of Lactobacillus salivarius SMXD51, isolated from the cecum of healthy chickens showing an activity against Campylobacter--the food-borne pathogen that is the most common cause of gastroenteritis in the European Union (EU)--and potentially interesting features for a probiotic strain, explaining our interest in it.

  14. N-Acylated and d Enantiomer Derivatives of a Nonamer Core Peptide of Lactoferricin B Showing Improved Antimicrobial Activity

    OpenAIRE

    Wakabayashi, Hiroyuki; Matsumoto, Hiroshi; Hashimoto, Koichi; Teraguchi, Susumu; Takase, Mitsunori; Hayasawa, Hirotoshi

    1999-01-01

    N-acylated or d enantiomer peptide derivatives based on the sequence RRWQWRMKK in lactoferricin B demonstrated antimicrobial activities greater than those of lactoferricin B against bacteria and fungi. The most potent peptide, conjugated with an 11-carbon-chain acyl group, showed two to eight times lower MIC than lactoferricin B.

  15. N-Acylated and D enantiomer derivatives of a nonamer core peptide of lactoferricin B showing improved antimicrobial activity.

    Science.gov (United States)

    Wakabayashi, H; Matsumoto, H; Hashimoto, K; Teraguchi, S; Takase, M; Hayasawa, H

    1999-05-01

    N-acylated or D enantiomer peptide derivatives based on the sequence RRWQWRMKK in lactoferricin B demonstrated antimicrobial activities greater than those of lactoferricin B against bacteria and fungi. The most potent peptide, conjugated with an 11-carbon-chain acyl group, showed two to eight times lower MIC than lactoferricin B.

  16. Mannose-binding Lectin and the Risk of HIV Transmission and Disease Progression in Children A Systematic Review

    NARCIS (Netherlands)

    Israëls, Joël; Scherpbier, Henriette J.; Frakking, Florine N. J.; van de Wetering, Marianne D.; Kremer, Leontien C. M.; Kuijpers, Taco W.

    2012-01-01

    Background: Mannose-binding lectin (MBL) can activate the complement system by binding to carbohydrates, such as those presented on the HIV virion surface. It is unclear whether genetically determined MBL deficiency is related to vertical HIV transmission and disease progression in HIV-infected

  17. A chimeric protein of aluminum-activated malate transporter generated from wheat and Arabidopsis shows enhanced response to trivalent cations.

    Science.gov (United States)

    Sasaki, Takayuki; Tsuchiya, Yoshiyuki; Ariyoshi, Michiyo; Ryan, Peter R; Yamamoto, Yoko

    2016-07-01

    TaALMT1 from wheat (Triticum aestivum) and AtALMT1 from Arabidopsis thaliana encode aluminum (Al)-activated malate transporters, which confer acid-soil tolerance by releasing malate from roots. Chimeric proteins from TaALMT1 and AtALMT1 (Ta::At, At::Ta) were previously analyzed in Xenopus laevis oocytes. Those studies showed that Al could activate malate efflux from the Ta::At chimera but not from At::Ta. Here, functions of TaALMT1, AtALMT1 and the chimeric protein Ta::At were compared in cultured tobacco BY-2 cells. We focused on the sensitivity and specificity of their activation by trivalent cations. The activation of malate efflux by Al was at least two-fold greater in the chimera than the native proteins. All proteins were also activated by lanthanides (erbium, ytterbium, gadolinium, and lanthanum), but the chimera again released more malate than TaALMT1 or AtALMT1. In Xenopus oocytes, Al, ytterbium, and erbium activated inward currents from the native TaALMT1 and the chimeric protein, but gadolinium only activated currents from the chimera. Lanthanum inhibited currents from both proteins. These results demonstrated that function of the chimera protein was altered compared to the native proteins and was more responsive to a range of trivalent cations when expressed in plant cells. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Pomegranate (Punica granatum Juice Shows Antioxidant Activity against Cutaneous Leishmaniasis-Induced Oxidative Stress in Female BALB/c Mice

    Directory of Open Access Journals (Sweden)

    Badriah Alkathiri

    2017-12-01

    Full Text Available Leishmania species are parasites that multiply within phagocytes and cause several clinical diseases characterized by single or multiple ulcerations. One of the complications that can induce tissue damage and the resulting scars is caused by secondary bacterial infections. Studies to find new, effective, and safe oral drugs for treating leishmaniasis are being conducted since several decades, owing to the problems associated with the use of antimonials available. Previously, the antiparasitic and antioxidant properties of Punica granatum (pomegranate, P. granatum have been reported. Therefore, in the present study, we aimed to investigate the antileishmanial activity of pomegranate aqueous juice in vitro and in female BALB/c mice. A 3-(4.5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay in Leishmania major promastigotes and alterations in the antioxidant status, liver function, and skin histological changes in L. major-infected mice orally treated with pomegranate juice alone and in combination with the antibiotic ciprofloxacin, were used to investigate the in vitro and in vivo antileishmanial activity of pomegranate juice, respectively. Oral P. granatum juice treatment significantly reduced the average size of cutaneous leishmaniasis lesions compared with that of the untreated mice. This antileishmanial activity of P. granatum was associated with enhanced antioxidant enzyme activities. Histopathological evaluation proved the antileishmanial activity of P. granatum, but did not reveal changes in the treated animals, compared to the positive control. In conclusion, P. granatum shows high and fast antileishmanial activity probably by boosting the endogenous antioxidant activity.

  19. Pomegranate (Punica granatum) Juice Shows Antioxidant Activity against Cutaneous Leishmaniasis-Induced Oxidative Stress in Female BALB/c Mice.

    Science.gov (United States)

    Alkathiri, Badriah; El-Khadragy, Manal F; Metwally, Dina M; Al-Olayan, Ebtesam M; Bakhrebah, Muhammed A; Abdel Moneim, Ahmed E

    2017-12-18

    Leishmania species are parasites that multiply within phagocytes and cause several clinical diseases characterized by single or multiple ulcerations. One of the complications that can induce tissue damage and the resulting scars is caused by secondary bacterial infections. Studies to find new, effective, and safe oral drugs for treating leishmaniasis are being conducted since several decades, owing to the problems associated with the use of antimonials available. Previously, the antiparasitic and antioxidant properties of Punica granatum (pomegranate, P. granatum ) have been reported. Therefore, in the present study, we aimed to investigate the antileishmanial activity of pomegranate aqueous juice in vitro and in female BALB/c mice. A 3-(4.5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in Leishmania major promastigotes and alterations in the antioxidant status, liver function, and skin histological changes in L. major -infected mice orally treated with pomegranate juice alone and in combination with the antibiotic ciprofloxacin, were used to investigate the in vitro and in vivo antileishmanial activity of pomegranate juice, respectively. Oral P. granatum juice treatment significantly reduced the average size of cutaneous leishmaniasis lesions compared with that of the untreated mice. This antileishmanial activity of P. granatum was associated with enhanced antioxidant enzyme activities. Histopathological evaluation proved the antileishmanial activity of P. granatum , but did not reveal changes in the treated animals, compared to the positive control. In conclusion, P. granatum shows high and fast antileishmanial activity probably by boosting the endogenous antioxidant activity.

  20. Structure of the C-type lectin carbohydrate recognition domain of human Tetranectin

    DEFF Research Database (Denmark)

    Kastrup, Jette Sandholm Jensen; Nielsen, Bettina Bryde; Rasmussen, Hanne B.

    1998-01-01

    Tetranectin (TN) is a C-type lectin involved in fibrinolysis, being the only endogenous ligand known to bind specifically to the kringle 4 domain of plasminogen. TN was originally isolated from plasma, but shows a wide tissue distribution. Furthermore, TN has been found in the extracellular matri...... molecules. One sulfate ion has been located at the surface of TN3, forming contacts to Glu120, Lys148, Asn106 of a symmetry-related molecule, and to an ethanol molecule....

  1. Pentaclethra macroloba tannins fractions active against methicillin-resistant staphylococcal and Gram-negative strains showing selective toxicity

    Directory of Open Access Journals (Sweden)

    Ivana Correa Ramos Leal

    2011-12-01

    Full Text Available The ethanol extract of the vegetal species Pentaclethra macroloba (Willd. Kuntze, Fabaceae, was fractioned and the antibacterial activity was determined. The active ethyl acetate (ea fraction showed activity against Gram-positive (Staphylococcus spp. and Enterococcus spp. and Gram-negative (Pseudomonas aeruginosa, Acinetobacter spp. and Klebsiella pneumoniae multiresistant bacteria. Gallic acid derivatives were identified as the main compounds in inactive subfractions from the ea fraction, while the active one afforded ellagic acid as the major constituent when submitted to acid hydrolysis reaction, which suggests the presence of hydrolysable tannins. The minimum bactericidal concentration analysis showed a bactericide mechanism of action for the tannin subfraction found. The antibacterial mechanism of action of the active tannin subfraction against S. aureus reference strains (ATCC 29213 e 33591 was proposed adopting an in vitro assay of protein synthesis inhibition. For this, bacterial cells were labeled with [35S] methionine in the presence of the subfraction. The protein synthesis inhibition was observed at 256 µg/mL of this subfraction. At this concentration it did not present cytotoxicity in eukaryotic cells by the neutral red technique, suggesting selective toxicity. The present study is the first in vitro investigation of the antibacterial properties of tannin fractions obtained from a polar extract of P. macroloba.

  2. Pentaclethra macroloba tannins fractions active against methicillin-resistant staphylococcal and Gram-negative strains showing selective toxicity

    Directory of Open Access Journals (Sweden)

    Ivana Correa Ramos Leal

    2011-08-01

    Full Text Available The ethanol extract of the vegetal species Pentaclethra macroloba (Willd. Kuntze, Fabaceae, was fractioned and the antibacterial activity was determined. The active ethyl acetate (ea fraction showed activity against Gram-positive (Staphylococcus spp. and Enterococcus spp. and Gram-negative (Pseudomonas aeruginosa, Acinetobacter spp. and Klebsiella pneumoniae multiresistant bacteria. Gallic acid derivatives were identified as the main compounds in inactive subfractions from the ea fraction, while the active one afforded ellagic acid as the major constituent when submitted to acid hydrolysis reaction, which suggests the presence of hydrolysable tannins. The minimum bactericidal concentration analysis showed a bactericide mechanism of action for the tannin subfraction found. The antibacterial mechanism of action of the active tannin subfraction against S. aureus reference strains (ATCC 29213 e 33591 was proposed adopting an in vitro assay of protein synthesis inhibition. For this, bacterial cells were labeled with [35S] methionine in the presence of the subfraction. The protein synthesis inhibition was observed at 256 µg/mL of this subfraction. At this concentration it did not present cytotoxicity in eukaryotic cells by the neutral red technique, suggesting selective toxicity. The present study is the first in vitro investigation of the antibacterial properties of tannin fractions obtained from a polar extract of P. macroloba.

  3. A cry in the dark: depressed mothers show reduced neural activation to their own infant’s cry

    Science.gov (United States)

    Ablow, Jennifer C.

    2012-01-01

    This study investigated depression-related differences in primiparous mothers’ neural response to their own infant’s distress cues. Mothers diagnosed with major depressive disorder (n = 11) and comparison mothers with no diagnosable psychopathology (n = 11) were exposed to their own 18-months-old infant’s cry sound, as well as unfamiliar infant’s cry and control sound, during functional neuroimaging. Depressed mothers’ response to own infant cry greater than other sounds was compared to non-depressed mothers’ response in the whole brain [false discovery rate (FDR) corrected]. A continuous measure of self-reported depressive symptoms (CESD) was also tested as a predictor of maternal response. Non-depressed mothers activated to their own infant’s cry greater than control sound in a distributed network of para/limbic and prefrontal regions, whereas depressed mothers as a group failed to show activation. Non-depressed compared to depressed mothers showed significantly greater striatal (caudate, nucleus accumbens) and medial thalamic activation. Additionally, mothers with lower depressive symptoms activated more strongly in left orbitofrontal, dorsal anterior cingulate and medial superior frontal regions. Non-depressed compared to depressed mothers activated uniquely to own infant greater than other infant cry in occipital fusiform areas. Disturbance of these neural networks involved in emotional response and regulation may help to explain parenting deficits in depressed mothers. PMID:21208990

  4. Altered glycosylation of complexed native IgG molecules is associated with disease activity of systemic lupus erythematosus.

    Science.gov (United States)

    Sjöwall, C; Zapf, J; von Löhneysen, S; Magorivska, I; Biermann, M; Janko, C; Winkler, S; Bilyy, R; Schett, G; Herrmann, M; Muñoz, L E

    2015-05-01

    In addition to the redundancy of the receptors for the Fc portion of immunoglobulins, glycans result in potential ligands for a plethora of lectin receptors found in immune effector cells. Here we analysed the exposure of glycans containing fucosyl residues and the fucosylated tri-mannose N-type core by complexed native IgG in longitudinal serum samples of well-characterized patients with systemic lupus erythematosus. Consecutive serum samples of a cohort of 15 patients with systemic lupus erythematosus during periods of increased disease activity and remission were analysed. All patients fulfilled the 1982 American College of Rheumatology classification criteria. Sera of 15 sex- and age-matched normal healthy blood donors served as controls. The levels and type of glycosylation of complexed random IgG was measured with lectin enzyme-immunosorbent assays. After specifically gathering IgG complexes from sera, biotinylated lectins Aleuria aurantia lectin and Lens culinaris agglutinin were employed to detect IgG-associated fucosyl residues and the fucosylated tri-mannose N-glycan core, respectively. In sandwich-ELISAs, IgG-associated IgM, IgA, C1q, C3c and C-reactive protein (CRP) were detected as candidates for IgG immune complex constituents. We studied associations of the glycan of complexed IgG and disease activity according to the physician's global assessment of disease activity and the systemic lupus erythematosus disease activity index 2000 documented at the moment of blood taking. Our results showed significantly higher levels of Aleuria aurantia lectin and Lens culinaris agglutinin binding sites exposed on IgG complexes of patients with systemic lupus erythematosus than on those of normal healthy blood donors. Disease activity in systemic lupus erythematosus correlated with higher exposure of Aleuria aurantia lectin-reactive fucosyl residues by immobilized IgG complexes. Top levels of Aleuria aurantia lectin-reactivity were found in samples taken during the

  5. Crotacetin, a novel snake venom C-type lectin, is homolog of convulxin

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    G. Rádis-Baptista

    2005-12-01

    Full Text Available Snake venom (sv C-type lectins encompass a group of hemorrhagic toxins, which are able to interfere with hemostasis. They share significant similarity in their primary structures with C-type lectins of other animals, and also present a conserved carbohydrate recognition domain (CRD. A very well studied sv C-type lectin is the heterodimeric toxin, convulxin (CVX, from the venoms of South American rattlesnakes, Crotalus durissus terrificus and C. d. cascavella. It consists of two subunits, alfa (CVXalpha , 13.9 kDa and beta (CVXbeta , 12.6 kDa, joined by inter and intra-chain disulfide bounds, and is arranged in a tetrameric alpha4beta4 conformation. Convulxin is able to activate platelet and induce their aggregation by acting via p62/GPVI collagen receptor. Several cDNA precursors, homolog of CVX subunits, were cloned by PCR homology screening. As determined by computational analysis, one of them, named crotacetin beta subunit, was predicted as a polypeptide with a tridimensional conformation very similar to other subunits of convulxin-like snake toxins. Crotacetin was purified from C. durissus venoms by gel permeation and reverse phase high performance liquid chromatography. The heterodimeric crotacetin is expressed in the venoms of several C. durissus subspecies, but it is prevalent in the venom of C. durissus cascavella. As inferred from homology modeling, crotacetin induces platelet aggregation but noticeably exhibits antimicrobial activity against Gram-positive and Gram-negative bacteria.

  6. Free-Standing Metal Oxide Nanoparticle Superlattices Constructed with Engineered Protein Containers Show in Crystallo Catalytic Activity.

    Science.gov (United States)

    Lach, Marcel; Künzle, Matthias; Beck, Tobias

    2017-12-11

    The construction of defined nanostructured catalysts is challenging. In previous work, we established a strategy to assemble binary nanoparticle superlattices with oppositely charged protein containers as building blocks. Here, we show that these free-standing nanoparticle superlattices are catalytically active. The metal oxide nanoparticles inside the protein scaffold are accessible for a range of substrates and show oxidase-like and peroxidase-like activity. The stable superlattices can be reused for several reaction cycles. In contrast to bulk nanoparticle-based catalysts, which are prone to aggregation and difficult to characterize, nanoparticle superlattices based on engineered protein containers provide an innovative synthetic route to structurally defined heterogeneous catalysts with control over nanoparticle size and composition. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Burn injury reveals altered phenotype in mannan-binding lectin-deficient mice

    DEFF Research Database (Denmark)

    Møller-Kristensen, Mette; Hamblin, Michael R; Thiel, Steffen

    2007-01-01

    Burn injury destroys skin, the second largest innate immune organ in the body, and triggers chaotic immune and inflammatory responses. The pattern recognition molecule, mannan-binding lectin (MBL), plays an important role in the first-line host defense against infectious agents. MBL initiates...... the lectin complement pathway and acts as an opsonin. Recent studies suggest that MBL also modulates inflammatory responses. We report that local responses after burn in MBL null mice differ from those found in wild-type (WT) mice in the following important biological markers: spontaneous eschar separation......, thinned epidermis and dermis, upregulation of soluble factors including cytokines, chemokines, cell adhesion molecules, a growth factor-binding protein, and matrix metalloproteinases. Mice lacking C1q, C4, or C3 did not show the lack of eschar separation seen in MBL null-burn phenotype. These findings...

  8. Modulation of ovomucoid-specific oral tolerance in mice fed plant extracts containing lectins

    DEFF Research Database (Denmark)

    Kjær, Tanja; Frøkiær, Hanne

    2002-01-01

    We investigated the effect of feeding extracts of four different legumes (red kidney bean (Phaseolus vulgaris), peanut (Arachis hypogaea), soyabean (Glycine max) and pea (Pisum sativum) on the specific immune response against a food protein. Mice were fed ovomucoid and the specific immune response...... influenced the immune response against ovomucoid; however, this was not as pronounced as for kidney bean and was only significant (Ppea extract was fed and peanut extract had a non-significant effect on induction of oral tolerance...... and on the general immune response. Plasma antibodies against kidney-bean lectin, but not against the three other legume lectins, were detected. Our current findings show that other dietary components can influence the specific immune response against food proteins. Various dietary components may thus contribute...

  9. Lactobacillus reuteri Surface Mucus Adhesins Upregulate Inflammatory Responses Through Interactions With Innate C-Type Lectin Receptors.

    Science.gov (United States)

    Bene, Krisztián P; Kavanaugh, Devon W; Leclaire, Charlotte; Gunning, Allan P; MacKenzie, Donald A; Wittmann, Alexandra; Young, Ian D; Kawasaki, Norihito; Rajnavolgyi, Eva; Juge, Nathalie

    2017-01-01

    The vertebrate gut symbiont Lactobacillus reuteri exhibits strain-specific adhesion and health-promoting properties. Here, we investigated the role of the mucus adhesins, CmbA and MUB, upon interaction of L. reuteri ATCC PTA 6475 and ATCC 53608 strains with human monocyte-derived dendritic cells (moDCs). We showed that mucus adhesins increased the capacity of L. reuteri strains to interact with moDCs and promoted phagocytosis. Our data also indicated that mucus adhesins mediate anti- and pro-inflammatory effects by the induction of interleukin-10 (IL-10), tumor necrosis factor alpha (TNF-α), IL-1β, IL-6, and IL-12 cytokines. L. reuteri ATCC PTA 6475 and ATCC 53608 were exclusively able to induce moDC-mediated Th1 and Th17 immune responses. We further showed that purified MUB activates moDCs and induces Th1 polarized immune responses associated with increased IFNγ production. MUB appeared to mediate these effects via binding to C-type lectin receptors (CLRs), as shown using cell reporter assays. Blocking moDCs with antibodies against DC-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) or Dectin-2 did not affect the uptake of the MUB-expressing strain, but reduced the production of TNF-α and IL-6 by moDCs significantly, in line with the Th1 polarizing capacity of moDCs. The direct interaction between MUB and CLRs was further confirmed by atomic force spectroscopy. Taken together these data suggest that mucus adhesins expressed at the cell surface of L. reuteri strains may exert immunoregulatory effects in the gut through modulating the Th1-promoting capacity of DCs upon interaction with C-type lectins.

  10. Actinobacteria from Termite Mounds Show Antiviral Activity against Bovine Viral Diarrhea Virus, a Surrogate Model for Hepatitis C Virus

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    Marina Aiello Padilla

    2015-01-01

    Full Text Available Extracts from termite-associated bacteria were evaluated for in vitro antiviral activity against bovine viral diarrhea virus (BVDV. Two bacterial strains were identified as active, with percentages of inhibition (IP equal to 98%. Both strains were subjected to functional analysis via the addition of virus and extract at different time points in cell culture; the results showed that they were effective as posttreatments. Moreover, we performed MTT colorimetric assays to identify the CC50, IC50, and SI values of these strains, and strain CDPA27 was considered the most promising. In parallel, the isolates were identified as Streptomyces through 16S rRNA gene sequencing analysis. Specifically, CDPA27 was identified as S. chartreusis. The CDPA27 extract was fractionated on a C18-E SPE cartridge, and the fractions were reevaluated. A 100% methanol fraction was identified to contain the compound(s responsible for antiviral activity, which had an SI of 262.41. GC-MS analysis showed that this activity was likely associated with the compound(s that had a peak retention time of 5 min. Taken together, the results of the present study provide new information for antiviral research using natural sources, demonstrate the antiviral potential of Streptomyces chartreusis compounds isolated from termite mounds against BVDV, and lay the foundation for further studies on the treatment of HCV infection.

  11. Appearance and cellular distribution of lectin-like receptors for alpha 1-acid glycoprotein in the developing rat testis

    DEFF Research Database (Denmark)

    Andersen, U O; Bøg-Hansen, T C; Kirkeby, S

    1996-01-01

    A histochemical avidin-biotin technique with three different alpha 1-acid glycoprotein glycoforms showed pronounced alterations in the cellular localization of two alpha 1-acid glycoprotein lectin-like receptors during cell differentiation in the developing rat testis. The binding of alpha 1-acid...

  12. L-rhamnose-binding lectins (RBLs) in Nile tilapia, Oreochromis niloticus: characterization and expression profiling in mucosal tissues

    Science.gov (United States)

    Rhamnose-binding lectins (RBLs) are crucial elements associated with innate immune responses to infections and have been characterized from a variety of teleost fishes. Our previous work highlighted a major role of a RBL (IpRBL1a) in mediating F. columnare adhesion and IpRBL1a showed higher expressi...

  13. C-Type Lectin Receptors in Asthma

    Directory of Open Access Journals (Sweden)

    Sabelo Hadebe

    2018-04-01

    Full Text Available Asthma is a heterogeneous disease that affects approximately 300 million people worldwide, largely in developed countries. The etiology of the disease is poorly understood, but is likely to involve specific innate and adaptive responses to inhaled microbial components that are found in allergens. Fungal-derived allergens represent a major contributing factor in the initiation, persistence, exacerbation, and severity of allergic asthma. C-type lectin like receptors, such as dectin-1, dectin-2, DC-specific intercellular adhesion molecule 3-grabbing nonintegrin, and mannose receptor, recognize many fungal-derived allergens and other structurally similar allergens derived from house dust mites (HDM. In some cases, the fungal derived allergens have been structurally and functionally identified alongside their respective receptors in both humans and mice. In this review, we discuss recent understanding on how selected fungal and HDM derived allergens as well as their known or unknown receptors shape allergic airway diseases.

  14. Crystallization of Ulex europaeus lectin I.

    Science.gov (United States)

    Vandonselaar, M; Delbaere, L T

    1994-10-21

    The lectin I from Ulex europaeus (UEAI) has a strong affinity for the H-type 2 human blood group determinant. Single crystals of UEAI have been grown in the monoclinic crystal system. Initial crystals were obtained after 11 months from a solution of 10 mg/ml protein, 40% 2,4-methylpentanediol and 0.1 N acetate buffer at pH 5.2. The technique of washing and reseeding was used to generate large suitable crystals. The space group is C2 with a = 78.84 A, b = 69.85 A, c = 120.62 A, beta = 108.74 degrees and Z = 4; there is one molecular dimer per asymmetric unit and the solvent content is estimated to be 58%. The crystals diffract to at least 2.8 A d spacings and are stable in the X-ray beam for more than three days.

  15. Genetics Home Reference: mannose-binding lectin deficiency

    Science.gov (United States)

    ... and Caregivers: Complement System Nobelprize.org: The Immune System - In More Detail Patient ... Sources for This Page Arora M, Munoz E, Tenner AJ. Identification of a site on mannan-binding lectin critical ...

  16. Human Lectins and Their Roles in Viral Infections

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    Christopher P. Mason

    2015-01-01

    Full Text Available Innate recognition of virus proteins is an important component of the immune response to viral pathogens. A component of this immune recognition is the family of lectins; pattern recognition receptors (PRRs that recognise viral pathogen-associated molecular patterns (PAMPs including viral glycoproteins. In this review we discuss the contribution of soluble and membrane-associated PRRs to immunity against virus pathogens, and the potential role of these molecules in facilitating virus replication. These processes are illustrated with examples of viruses including human immunodeficiency virus (HIV, hepatitis C virus (HCV and Ebola virus (EBOV. We focus on the structure, function and genetics of the well-characterised C-type lectin mannose-binding lectin, the ficolins, and the membrane-bound CD209 proteins expressed on dendritic cells. The potential for lectin-based antiviral therapies is also discussed.

  17. Lectins stain cells differentially in the coral, Montipora capitata

    Science.gov (United States)

    Work, Thierry M.; Farah, Yael

    2014-01-01

    A limitation in our understanding of coral disease pathology and cellular pathogenesis is a lack of reagents to characterize coral cells. We evaluated the utility of plant lectins to stain tissues of a dominant coral, Montipora capitata, from Hawaii. Of 22 lectins evaluated, nine of these stained structures in the upper or basal body wall of corals. Specific structures revealed by lectins that were not considered distinct or evident on routine hematoxylin and eosin sections of coral tissues included apical and basal granules in gastrodermis and epidermis, cnidoglandular tract and actinopharynx cell surface membranes, capsules of mature holotrichous isorhizas, and perivitelline and periseminal cells. Plant lectins could prove useful to further our understanding of coral physiology, anatomy, cell biology, and disease pathogenesis.

  18. Activity/inactivity circadian rhythm shows high similarities between young obesity-induced rats and old rats.

    Science.gov (United States)

    Bravo Santos, R; Delgado, J; Cubero, J; Franco, L; Ruiz-Moyano, S; Mesa, M; Rodríguez, A B; Uguz, C; Barriga, C

    2016-03-01

    The objective of the present study was to compare differences between elderly rats and young obesity-induced rats in their activity/inactivity circadian rhythm. The investigation was motivated by the differences reported previously for the circadian rhythms of both obese and elderly humans (and other animals), and those of healthy, young or mature individuals. Three groups of rats were formed: a young control group which was fed a standard chow for rodents; a young obesity-induced group which was fed a high-fat diet for four months; and an elderly control group with rats aged 2.5 years that was fed a standard chow for rodents. Activity/inactivity data were registered through actimetry using infrared actimeter systems in each cage to detect activity. Data were logged on a computer and chronobiological analysis were performed. The results showed diurnal activity (sleep time), nocturnal activity (awake time), amplitude, acrophase, and interdaily stability to be similar between the young obesity-induced group and the elderly control group, but different in the young control group. We have concluded that obesity leads to a chronodisruption status in the body similar to the circadian rhythm degradation observed in the elderly.

  19. The novel oral glucan synthase inhibitor SCY-078 shows in vitro activity against sessile and planktonic Candida spp.

    Science.gov (United States)

    Marcos-Zambrano, Laura Judith; Gómez-Perosanz, Marta; Escribano, Pilar; Bouza, Emilio; Guinea, Jesús

    2017-07-01

    We studied the antifungal activity of SCY-078 (an orally bioavailable 1,3-β -d- glucan synthesis inhibitor), micafungin and fluconazole against the planktonic and sessile forms of 178 Candida and non- Candida isolates causing fungaemia in patients recently admitted to a large European hospital. The in vitro activity of SCY-078, micafungin and fluconazole against the planktonic form of the isolates was assessed using EUCAST EDef 7.3 and CLSI M27-A3. Antibiofilm activity was assessed using the XTT reduction assay. SCY-078 and micafungin showed potent in vitro activity against Candida and non- Candida isolates. The in vitro activity of both drugs was similar, but SYC-078 displayed significantly lower MIC values than micafungin against Candida parapsilosis and non- Candida isolates, whereas micafungin displayed significantly lower MIC values for the remaining species ( P  Candida glabrata , in which the micafungin sessile MIC values were significantly lower ( P  Candida isolates in both sessile and planktonic forms is comparable to that of micafungin. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Quercetin and quercetin 3-O-glycosides from Bauhinia longifolia (Bong.) Steud. show anti-Mayaro virus activity.

    Science.gov (United States)

    dos Santos, Alda E; Kuster, Ricardo M; Yamamoto, Kristie A; Salles, Tiago S; Campos, Renata; de Meneses, Marcelo D F; Soares, Márcia R; Ferreira, Davis

    2014-03-28

    The arthropod-borne Mayaro virus (MAYV) causes 'Mayaro fever', a disease of medical significance, primarily affecting individuals in permanent contact with forested areas in tropical South America. Recently, MAYV has attracted attention due to its likely urbanization. Currently, there are no licensed drugs against most mosquito-transmitted viruses. Here, we investigated the in vitro anti-MAYV activity of the flavonoids quercetin and its derivatives from the Brazilian shrub Bauhinia longifolia (Bong.) Steud. Flavonoids were purified by chromatographic fractionation from leaf extracts of B. longifolia and chemically identified as quercetin and quercetin glycosides using spectroscopic techniques. Cytotoxicity of purified flavonoids and of EtOAc- and n-BuOH-containing flavonoid mixtures was measured by the dye-uptake assay while their antiviral activity was evaluated by a virus yield inhibition assay. The following flavonoids were purified from B. longifolia leaves: non-glycosylated quercetin and its glycosides guaijaverin, quercitrin, isoquercitrin, and hyperin. EtOAc and n-BuOH fractions containing these flavonoids demonstrated the highest antiviral activity of all tested substances, while quercetin had the highest antiviral activity amongst purified flavonoids. Quercetin, EtOAc, or n-BuOH fractions inhibited MAYV production by more than 90% at 25 μg/mL, displaying a stronger antiviral effect than the licensed antiviral ribavirin. A mixture of the isomers isoquercitrin and hyperin had a modest antiviral effect (IC90 = 104.9), while guaijaverin and quercitrin did not show significant antiviral activity. B. longifolia is a good source of flavonoids with anti-Mayaro virus activity. This is the first report of the activity of quercetin and its derivatives against an alphavirus.

  1. Expression analysis of carbohydrate antigens in ductal carcinoma in situ of the breast by lectin histochemistry

    Directory of Open Access Journals (Sweden)

    Kieber-Emmons Thomas

    2008-05-01

    Full Text Available Abstract Background The number of breast cancer patients diagnosed with ductal carcinoma in situ (DCIS continues to grow. Laboratory and clinical data indicate that DCIS can progress to invasive disease. Carbohydrate-mediated cell-cell adhesion and tumor-stroma interaction play crucial roles in tumorigenesis and tumor aggressive behavior. Breast carcinogenesis may reflect quantitative as well as qualitative changes in oligosaccharide expression, which may provide a useful tool for early detection of breast cancer. Because tumor-associated carbohydrate antigens (TACA are implicated in tumor invasion and metastasis, the purpose of this study was to assess the expression of selected TACA by lectin histochemistry on DCIS specimens from the archival breast cancer tissue array bank of the University of Arkansas for Medical Sciences. Methods For detection of TACA expression, specimens were stained with Griffonia simplicifolia lectin-I (GS-I and Vicia vilosa agglutinin (VVA. We studied associations of lectin reactivity with established prognostic factors, such as tumor size, tumor nuclear grade, and expression of Her-2/neu, p53 mutant and estrogen and progesterone receptors. Results We observed that both lectins showed significant associations with nuclear grade of DCIS. DCIS specimens with nuclear grades II and III showed significantly more intense reactivity than DCIS cases with nuclear grade I to GS-1 (Mean-score chi-square = 17.60, DF = 2; P = 0.0002 and VVA (Mean-score chi-square = 15.72, DF = 2; P = 0.0004. Conclusion The results suggest that the expression of VVA- and GS-I-reactive carbohydrate antigens may contribute to forming higher grade DCIS and increase the recurrence risk.

  2. Expression analysis of carbohydrate antigens in ductal carcinoma in situ of the breast by lectin histochemistry

    International Nuclear Information System (INIS)

    Korourian, Soheila; Siegel, Eric; Kieber-Emmons, Thomas; Monzavi-Karbassi, Behjatolah

    2008-01-01

    The number of breast cancer patients diagnosed with ductal carcinoma in situ (DCIS) continues to grow. Laboratory and clinical data indicate that DCIS can progress to invasive disease. Carbohydrate-mediated cell-cell adhesion and tumor-stroma interaction play crucial roles in tumorigenesis and tumor aggressive behavior. Breast carcinogenesis may reflect quantitative as well as qualitative changes in oligosaccharide expression, which may provide a useful tool for early detection of breast cancer. Because tumor-associated carbohydrate antigens (TACA) are implicated in tumor invasion and metastasis, the purpose of this study was to assess the expression of selected TACA by lectin histochemistry on DCIS specimens from the archival breast cancer tissue array bank of the University of Arkansas for Medical Sciences. For detection of TACA expression, specimens were stained with Griffonia simplicifolia lectin-I (GS-I) and Vicia vilosa agglutinin (VVA). We studied associations of lectin reactivity with established prognostic factors, such as tumor size, tumor nuclear grade, and expression of Her-2/neu, p53 mutant and estrogen and progesterone receptors. We observed that both lectins showed significant associations with nuclear grade of DCIS. DCIS specimens with nuclear grades II and III showed significantly more intense reactivity than DCIS cases with nuclear grade I to GS-1 (Mean-score chi-square = 17.60, DF = 2; P = 0.0002) and VVA (Mean-score chi-square = 15.72, DF = 2; P = 0.0004). The results suggest that the expression of VVA- and GS-I-reactive carbohydrate antigens may contribute to forming higher grade DCIS and increase the recurrence risk

  3. Human surfactant protein D: SP-D contains a C-type lectin carbohydrate recognition domain.

    Science.gov (United States)

    Rust, K; Grosso, L; Zhang, V; Chang, D; Persson, A; Longmore, W; Cai, G Z; Crouch, E

    1991-10-01

    Lung surfactant protein D (SP-D) shows calcium-dependent binding to specific saccharides, and is similar in domain structure to certain members of the calcium-dependent (C-type) lectin family. Using a degenerate oligomeric probe corresponding to a conserved peptide sequence derived from the amino-terminus of the putative carbohydrate binding domain of rat and bovine SP-D, we screened a human lung cDNA library and isolated a 1.4-kb cDNA for the human protein. The relationship of the cDNA to SP-D was established by several techniques including amino-terminal microsequencing of SP-D-derived peptides, and immunoprecipitation of translation products of transcribed mRNA with monospecific antibodies to SP-D. In addition, antibodies to a synthetic peptide derived from a predicted unique epitope within the carbohydrate recognition domain of SP-D specifically reacted with SP-D. DNA sequencing demonstrated a noncollagenous carboxy-terminal domain that is highly homologous with the carboxy-terminal globular domain of previously described C-type lectins. This domain contains all of the so-called "invariant residues," including four conserved cysteine residues, and shows high homology with the mannose-binding subfamily of C-type lectins. Sequencing also demonstrated an amino-terminal collagenous domain that contains an uninterrupted sequence of 59 Gly-X-Y triplets and that also contains the only identified consensus for asparagine-linked oligosaccharides. The studies demonstrate that SP-D is a member of the C-type lectin family, and confirm predicted structural similarities to conglutinin, SP-D, and the serum mannose binding proteins.

  4. Novel animal defenses against predation: a snail egg neurotoxin combining lectin and pore-forming chains that resembles plant defense and bacteria attack toxins.

    Directory of Open Access Journals (Sweden)

    Marcos Sebastián Dreon

    Full Text Available Although most eggs are intensely predated, the aerial egg clutches from the aquatic snail Pomacea canaliculata have only one reported predator due to unparalleled biochemical defenses. These include two storage-proteins: ovorubin that provides a conspicuous (presumably warning coloration and has antinutritive and antidigestive properties, and PcPV2 a neurotoxin with lethal effect on rodents. We sequenced PcPV2 and studied whether it was able to withstand the gastrointestinal environment and reach circulation of a potential predator. Capacity to resist digestion was assayed using small-angle X-ray scattering (SAXS, fluorescence spectroscopy and simulated gastrointestinal proteolysis. PcPV2 oligomer is antinutritive, withstanding proteinase digestion and displaying structural stability between pH 4.0-10.0. cDNA sequencing and protein domain search showed that its two subunits share homology with membrane attack complex/perforin (MACPF-like toxins and tachylectin-like lectins, a previously unknown structure that resembles plant Type-2 ribosome-inactivating proteins and bacterial botulinum toxins. The protomer has therefore a novel AB toxin combination of a MACPF-like chain linked by disulfide bonds to a lectin-like chain, indicating a delivery system for the former. This was further supported by observing PcPV2 binding to glycocalix of enterocytes in vivo and in culture, and by its hemaggutinating, but not hemolytic activity, which suggested an interaction with surface oligosaccharides. PcPV2 is able to get into predator's body as evidenced in rats and mice by the presence of circulating antibodies in response to sublethal oral doses. To our knowledge, a lectin-pore-forming toxin has not been reported before, providing the first evidence of a neurotoxic lectin in animals, and a novel function for ancient and widely distributed proteins. The acquisition of this unique neurotoxic/antinutritive/storage protein may confer the eggs a survival advantage

  5. Transgenic alfalfa (Medicago sativa) with increased sucrose phosphate synthase activity shows enhanced growth when grown under N2-fixing conditions.

    Science.gov (United States)

    Gebril, Sayed; Seger, Mark; Villanueva, Fabiola Muro; Ortega, Jose Luis; Bagga, Suman; Sengupta-Gopalan, Champa

    2015-10-01

    Overexpression of SPS in alfalfa is accompanied by early flowering, increased plant growth and an increase in elemental N and protein content when grown under N2-fixing conditions. Sucrose phosphate synthase (SPS; EC 2.3.1.14) is the key enzyme in the synthesis of sucrose in plants. The outcome of overexpression of SPS in different plants using transgenic approaches has been quite varied, but the general consensus is that increased SPS activity is associated with the production of new sinks and increased sink strength. In legumes, the root nodule is a strong C sink and in this study our objective was to see how increasing SPS activity in a legume would affect nodule number and function. Here we have transformed alfalfa (Medicago sativa, cv. Regen SY), with a maize SPS gene driven by the constitutive CaMV35S promoter. Our results showed that overexpression of SPS in alfalfa, is accompanied by an increase in nodule number and mass and an overall increase in nitrogenase activity at the whole plant level. The nodules exhibited an increase in the level of key enzymes contributing to N assimilation including glutamine synthetase and asparagine synthetase. Moreover, the stems of the transformants showed higher level of the transport amino acids, Asx, indicating increased export of N from the nodules. The transformants exhibited a dramatic increase in growth both of the shoots and roots, and earlier flowering time, leading to increased yields. Moreover, the transformants showed an increase in elemental N and protein content. The overall conclusion is that increased SPS activity improves the N status and plant performance, suggesting that the availability of more C in the form of sucrose enhances N acquisition and assimilation in the nodules.

  6. Autistic adolescents show atypical activation of the brain's mentalizing system even without a prior history of mentalizing problems.

    Science.gov (United States)

    White, Sarah J; Frith, Uta; Rellecke, Julian; Al-Noor, Zainab; Gilbert, Sam J

    2014-04-01

    Some autistic children pass classic Theory of Mind (ToM) tasks that others fail, but the significance of this finding is at present unclear. We identified two such groups of primary school age (labelled ToM+ and ToM-) and a matched comparison group of typically developing children (TD). Five years later we tested these participants again on a ToM test battery appropriate for adolescents and conducted an fMRI study with a story based ToM task. We also assessed autistic core symptoms at these two time points. At both times the ToM- group showed more severe social communication impairments than the ToM+ group, and while showing an improvement in mentalizing performance, they continued to show a significant impairment compared to the NT group. Two independent ROI analyses of the BOLD signal showed activation of the mentalizing network including medial prefrontal cortex, posterior cingulate and lateral temporal cortices. Strikingly, both ToM+ and ToM- groups showed very similar patterns of heightened activation in comparison with the NT group. No differences in other brain regions were apparent. Thus, autistic adolescents who do not have a history of mentalizing problems according to our ToM battery showed the same atypical neurophysiological response during mentalizing as children who did have such a history. This finding indicates that heterogeneity at the behavioural level may nevertheless map onto a similar phenotype at the neuro-cognitive level. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. "Click" saccharide/beta-lactam hybrids for lectin inhibition.

    Science.gov (United States)

    Palomo, Claudio; Aizpurua, Jesus M; Balentová, Eva; Azcune, Itxaso; Santos, J Ignacio; Jiménez-Barbero, Jesús; Cañada, Javier; Miranda, José Ignacio

    2008-06-05

    Hybrid glycopeptide beta-lactam mimetics designed to bind lectins or carbohydrate recognition domains in selectins have been prepared according to a "shape-modulating linker" design. This approach was implemented using the azide-alkyne "click" cycloaddition reaction, and as shown by NMR/MD experiments, binding of the resulting mimetics to Ulex Europaeus Lectin-1 (UEL-1) occurred after a "bent-to-extended" conformational change around a partially rotatable triazolylmethylene moiety.

  8. Identification and characterization of a novel legume-like lectin ...

    Indian Academy of Sciences (India)

    A legume-type lectin (L-lectin) gene of the red algae Gracilaria fisheri (GFL) was cloned by rapid amplification of cDNA ends (RACE). The full-length cDNA of GFL was 1714 bp and contained a 1542 bp open reading frame encoding 513 amino acids with a predicted molecular mass of 56.5 kDa. Analysis of the putative ...

  9. Proteomic Analysis Shows Constitutive Secretion of MIF and p53-associated Activity of COX-2−/− Lung Fibroblasts

    Directory of Open Access Journals (Sweden)

    Mandar Dave

    2017-12-01

    Full Text Available The differential expression of two closelyassociated cyclooxygenase isozymes, COX-1 and COX-2, exhibited functions beyond eicosanoid metabolism. We hypothesized that COX-1 or COX-2 knockout lung fibroblasts may display altered protein profiles which may allow us to further differentiate the functional roles of these isozymes at the molecular level. Proteomic analysis shows constitutive production of macrophage migration inhibitory factor (MIF in lung fibroblasts derived from COX-2−/− but not wild-type (WT or COX-1−/− mice. MIF was spontaneously released in high levels into the extracellular milieu of COX2−/− fibroblasts seemingly from the preformed intracellular stores, with no change in the basal gene expression of MIF. The secretion and regulation of MIF in COX-2−/− was “prostaglandin-independent.” GO analysis showed that concurrent with upregulation of MIF, there is a significant surge in expression of genes related to fibroblast growth, FK506 binding proteins, and isomerase activity in COX-2−/− cells. Furthermore, COX-2−/− fibroblasts also exhibit a significant increase in transcriptional activity of various regulators, antagonists, and co-modulators of p53, as well as in the expression of oncogenes and related transcripts. Integrative Oncogenomics Cancer Browser (IntroGen analysis shows downregulation of COX-2 and amplification of MIF and/or p53 activity during development of glioblastomas, ependymoma, and colon adenomas. These data indicate the functional role of the MIF-COX-p53 axis in inflammation and cancer at the genomic and proteomic levels in COX-2-ablated cells. This systematic analysis not only shows the proinflammatory state but also unveils a molecular signature of a pro-oncogenic state of COX-1 in COX-2 ablated cells.

  10. Polypyridylruthenium(II complexes exert in vitro and in vivo nematocidal activity and show significant inhibition of parasite acetylcholinesterases

    Directory of Open Access Journals (Sweden)

    Madhu Sundaraneedi

    2018-04-01

    Full Text Available Over 4.5 billion people are at risk of infection with soil transmitted helminths and there are concerns about the development of resistance to the handful of frontline nematocides in endemic populations. We investigated the anti-nematode efficacy of a series of polypyridylruthenium(II complexes and showed they were active against L3 and adult stages of Trichuris muris, the rodent homologue of the causative agent of human trichuriasis, T. trichiura. One of the compounds, Rubb12-mono, which was among the most potent in its ability to kill L3 (IC50 = 3.1 ± 0.4 μM and adult (IC50 = 5.2 ± 0.3 μM stage worms was assessed for efficacy in a mouse model of trichuriasis by administering 3 consecutive daily oral doses of the drug 3 weeks post infection with the murine whipworm Trichuris muris. Mice treated with Rubb12-mono showed an average 66% reduction (P = 0.015 in faecal egg count over two independent trials. The drugs partially exerted their activity through inhibition of acetylcholinesterases, as worms treated in vitro and in vivo showed significant decreases in the activity of this class of enzymes. Our data show that ruthenium complexes are effective against T. muris, a model gastro-intestinal nematode and soil-transmitted helminth. Further, knowledge of the target of ruthenium drugs can facilitate modification of current compounds to identify analogues which are even more effective and selective against Trichuris and other helminths of human and veterinary importance. Keywords: Acetylcholinesterase, Trichuris muris, Ruthenium complex, Anthelmintic

  11. Simian Immunodeficiency Virus and Human Immunodeficiency Virus Type 1 Nef Proteins Show Distinct Patterns and Mechanisms of Src Kinase Activation

    Science.gov (United States)

    Greenway, Alison L.; Dutartre, Hélène; Allen, Kelly; McPhee, Dale A.; Olive, Daniel; Collette, Yves

    1999-01-01

    The nef gene from human and simian immunodeficiency viruses (HIV and SIV) regulates cell function and viral replication, possibly through binding of the nef product to cellular proteins, including Src family tyrosine kinases. We show here that the Nef protein encoded by SIVmac239 interacts with and also activates the human Src kinases Lck and Hck. This is in direct contrast to the inhibitory effect of HIV type 1 (HIV-1) Nef on Lck catalytic activity. Unexpectedly, however, the interaction of SIV Nef with human Lck or Hck is not mediated via its consensus proline motif, which is known to mediate HIV-1 Nef binding to Src homology 3 (SH3) domains, and various experimental analyses failed to show significant interaction of SIV Nef with the SH3 domain of either kinase. Instead, SIV Nef can bind Lck and Hck SH2 domains, and its N-terminal 50 amino acid residues are sufficient for Src kinase binding and activation. Our results provide evidence for multiple mechanisms by which Nef binds to and regulates Src kinases. PMID:10364375

  12. Glycoconjugate sugar residues in the chick embryo developing lung: a lectin histochemical study.

    Science.gov (United States)

    Gheri, G; Sgambati, E; Bryk, S G

    2000-03-01

    A lectin histochemical study was performed to investigate the distribution and changes of the oligosaccharidic component of the glycoconjugates in the lung of chick embryos, of 1-day-old chick, and of the adult animal. For this purpose, a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, Con A, LTA, and UEA I) were employed. During the first phase of parabronchi and atria formation, D-galactose-(beta1-->3)-N-acetyl-D-galactosamine, beta-N-acetyl-D-galactosamine, D-glucosamine, alpha-D-mannose, and sialic acid, present at the level of the surface and of cytoplasmic granules of the lining epithelial cells, seem to play a role in regulating morphogenetic phenomena. In the subsequent phases, the parabronchial lumen and the atrial cavities were characterized by the presence of lectin-reactive material rich in terminal D-galactose-(beta1-->3)-N-acetyl-D-galactosamine, beta-N-acetyl-D-galactosamine, D-glucosamine and alpha-D-mannose. From day 18 onwards and immediately after hatching, the free border of the cells lining the air capillaries was characterized by the presence of beta-N-acetyl-D-galactosamine and alpha-D-mannose. The appearance of these sugar residues was concomitant with the beginning of respiratory activity. Copyright 2000 Wiley-Liss, Inc.

  13. A sheep hydatid cyst glycoprotein as receptors for three toxic lectins, as well as Abrus precatorius and Ricinus communis agglutinins.

    Science.gov (United States)

    Wu, A M; Song, S C; Wu, J H; Pfüller, U; Chow, L P; Lin, J Y

    1995-01-18

    The binding properties of a glycoprotein with blood group P1 specificity isolated from sheep hydatid cyst fluid with Gal and GalNAc specific lectins was investigated by quantitative precipitin and precipitin inhibition assays. The glycoprotein completely precipitated Ricinus communis agglutinin (RCA1), Abrus precatorius agglutinin (APA) and Mistletoe toxic lectin-I (ML-I). Only 1.0 microgram of P1 glycoprotein was required to precipitate 50% of 5.1 micrograms ML-I nitrogen. It also reacted well with abrin-a and ricin, precipitating over 73% of the lectin nitrogen added, but poorly or weakly with Dolichos biflorus (DBL), Vicia villosa (VVL, a mixture of A4, A2B2 and B4), VVL-B4, Arachis hypogaea (PNA), Maclura pomifera (MPL), Bauchinia purpurea alba (BPL) and Wistaria floribunda (WFL) lectins. When an inhibition assay in the range of 5.1 micrograms N to 5.9 micrograms N of lectins (ML-I, abrin-a; ricin, RCA1, and APA, and 10 micrograms P1 active glycoprotein interaction was performed; from 76 to 100% of the precipitations were inhibited by 0.44 and 0.52 mumol of Gal alpha 1-->4Gal and Gal beta 1-->4GlcNAc, respectively, but not or insignificantly with 1.72 mumol of GlcNAc. The Gal alpha 1-->4Gal disaccharide found in this P1 active glycoprotein is a frequently occurring sequence of many glycosphingolipids located at the surface of mammalian cell membranes, especially human erythrocytes and intestinal cells for ligand binding and microbial toxin attachment. The present finding suggests that the Gal alpha 1-->4Gal beta 1-->4GlcNAc sequence in this P1 active glycoprotein is one of the best glycoprotein receptors for three toxic lectins (ricin, abrin-a, and ML-I) as well as for APA, and RCA1, and the result of inhibition assay implies that these lectins are recognizing part or all of the Gal alpha 1-->4Gal beta 1-->4GlcNAc sequence in the P1 active glycoprotein.

  14. Crude extract and fractions from Eugenia uniflora Linn leaves showed anti-inflammatory, antioxidant, and antibacterial activities.

    Science.gov (United States)

    Falcão, Tamires Rocha; de Araújo, Aurigena Antunes; Soares, Luiz Alberto Lira; de Moraes Ramos, Rhayanne Thaís; Bezerra, Isabelle Cristinne Ferraz; Ferreira, Magda Rhayanny Assunção; de Souza Neto, Manoel André; Melo, Maria Celeste Nunes; de Araújo, Raimundo Fernandes; de Aguiar Guerra, Andreza Conceição Véras; de Medeiros, Juliana Silva; Guerra, Gerlane Coelho Bernardo

    2018-03-09

    This study showed phytochemical composition and evaluates the anti-inflammatory, and analgesic activities of crude extract (CE) and fractions from E. uniflora Linn leaves. Polyphenols present in crude extract (CE), in aqueous fraction (AqF), and ethyl acetate (EAF) treated fractions from E. uniflora Linn leaves were shown by chromatographic analysis in order to conduct a phytochemical characterization. Antibacterial activity was evaluated based on minimum inhibitory concentrations (MICs) determined using the agar dilution method. Doses of 50, 100, and 200 mg/kg of the CE and fractions were applied for conducting in vivo models (male Swiss mice, 8-10 weeks old). The peritonitis experimental model was induced by carrageenan following of Myeloperoxidase activity (MPO), Total glutathione and malondialdehyde (MDA), IL-1β and TNF-α levels by spectroscopic UV/VIS analysis. Antinociceptive activity was evaluated based on an abdominal writhing model and hot plate test. The results were statistically evaluated using one-way analysis of variance (ANOVA), followed by Bonferroni's post-hoc test. The level of statistical significance was p fractions obtained from E. uniflora Linn leaves (0.05-0.87%w/w, 0.20-0.32%w/w, and 1.71-6.56%w/w, respectively). In general, the CE had lower MIC values than the fractions, including the lowest MIC against the MRSA strain. The CE and AqF also significantly reduced leukocyte migration and MPO activity (p fractions exhibited an antioxidant effect (p fractions from the studied E. uniflora Linn leaves exhibited antibacterial, anti-inflammatory, antioxidant, and analgesic activity in the performed assays.

  15. Immunohistochemical, lectin histochemical and ultrastructural studies of canine transmissible venereal tumor in Brazil

    Directory of Open Access Journals (Sweden)

    Mariana B. Mascarenhas

    Full Text Available ABSTRACT: Canine transmissible venereal tumor (CTVT is a naturally occurring contagious round-cell neoplasia, with poorly understood origin and transmission. This study aims to further investigate the tumor nature through immunohistochemistry, lectin histochemistry and transmission electron microscopy (TEM analysis, and to provide support for diagnostic and differential diagnoses of CTVT. Immunohistochemistry was performed in 10 genital and six exclusively extragenital tumors, which were previously diagnosed by citology and histopathology. CTVT samples were incubated with biotinylated antibodies to specific membrane and cytoplasmic antigens (anti-lysozyme, anti-macrophage, anti-vimentin, anti-CD18, monoclonal anti-CD117, monoclonal anti-CD3, polyclonal anti-CD117, polyclonal CD3 and anti-CD79a, followed by the avidin-biotin-peroxidase complex technique. The lectins Con A, DBA, SBA, PNA, UEA-1, WGA, sWGA, GSL, JSA, PSA, PHA-L, PHA-E and RCA were additionally tested in four genital CTVTs and TEM was performed in eight genital tumors. The anti-vimentin antibody revealed strong immunoreactivity to neoplastic cells in all the assessed samples (16/16. The polyclonal anti-CD3 antibodies showed moderate to strong immunoreactivity in fourteen (14/16 and the polyclonal anti-CD117 in fifteen cases (15/16. There was no immunoreactivity to anti-lysozyme, anti-macrophage, anti-CD18, monoclonal anti-CD117, monoclonal anti-CD3 and anti-CD79a antibodies. At lectin histochemistry, it was observed strong staining of tumor cells to Con-A, PHA-L and RCA. There was no histopathological and immunoreactivity differences between genital and extragenital CTVTs. These findings do not support the hypothesis of histiocytic origin of CTVT. In contrast, the lectin histochemical results were similar to cells from lymphoid/myeloid origin.

  16. Plectasin shows intracellular activity against Staphylococcus aureus in human THP-1 monocytes and in a mouse peritonitis model

    DEFF Research Database (Denmark)

    Brinch, Karoline Sidelmann; Sandberg, Anne; Baudoux, Pierre

    2009-01-01

    was maintained (maximal relative efficacy [E(max)], 1.0- to 1.3-log reduction in CFU) even though efficacy was inferior to that of extracellular killing (E(max), >4.5-log CFU reduction). Animal studies included a novel use of the mouse peritonitis model, exploiting extra- and intracellular differentiation assays...... concentration. These findings stress the importance of performing studies of extra- and intracellular activity since these features cannot be predicted from traditional MIC and killing kinetic studies. Application of both the THP-1 and the mouse peritonitis models showed that the in vitro results were similar...

  17. Crystallization and preliminary X-ray study of the common edible mushroom (Agaricus bisporus) lectin.

    Science.gov (United States)

    Carrizo, Maria E; Irazoqui, Fernando J; Lardone, Ricardo D; Nores, Gustavo A; Curtino, Juan A; Capaldi, Stefano; Perduca, Massimiliano; Monaco, Hugo L

    2004-04-01

    The lectin from the common edible mushroom Agaricus bisporus (ABL) belongs to the group of proteins that have the property of binding the Thomsen-Friedenreich antigen (T-antigen) selectively and with high affinity, but does not show any sequence similarity to the other proteins that share this property. The ABL sequence is instead similar to those of members of the saline-soluble fungal lectins, a protein family with pesticidal properties. The presence of different isoforms has been reported. It has been found that in order to be able to grow diffraction-quality crystals of the lectin, it is essential to separate the isoforms, which was performed by preparative isoelectric focusing. Using standard procedures, it was possible to crystallize the most basic of the forms by either vapour diffusion or equilibrium dialysis, but attempts to grow crystals of the other more acidic forms were unsuccessful. The ABL crystals belong to the orthorhombic space group C222(1), with unit-cell parameters a = 93.06, b = 98.16, c = 76.38 A, and diffract to a resolution of 2.2 A on a conventional source at room temperature. It is expected that the solution of this structure will yield further valuable information on the differences in the T-antigen-binding folds and will perhaps help to clarify the details of the ligand binding to the protein.

  18. Sugar residues content and distribution in atrophic and hyperplastic postmenopausal human endometrium: lectin histochemistry.

    Science.gov (United States)

    Gheri, G; Bryk, S G; Taddei, G; Moncini, D; Noci, I

    1996-10-01

    A lectin histochemical study was performed to investigate the glycoconjugate saccharidic moieties of the human postmenopausal endometrium (14 atrophic and 15 hyperplastic). For this purpose a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, ConA, LTA and UEA I) was used. No differences in lectin binding between atrophic and hyperplastic endometria were observed. This investigation allowed us to provide a basic picture of the oligosaccharidic distribution in postmenopausal endometria. The data on the saccharidic distribution at the postmenopausal endometria showed a large amount of sugar residues at all the investigated sites, i.e. the lining and glandular epithelium, the stroma and the vessels (capillary and large vessels). Furthermore, at the endometrial lining epithelium, at the glands and at the wall of the blood vessels of some postmenopausal women the presence of alpha-L-fucosyl residues which bind via alpha (1-6) linkage to penultimate glucosaminyl residues and/or difucosylated oligosaccharides was demonstrated for the first time.

  19. Upgrading wholesomeness of soybeans through radiation deactivation of toxic lectin content

    International Nuclear Information System (INIS)

    Farag, D.M.

    1994-01-01

    The biological effects of raw soybeans were investigated through feeding experiments on rats and the wholesomeness of soybeans after radiation deactivation of toxic lectin present in seeds has been evaluated. The injection of crude lectins extracted from 0.15 g raw soybean by intraperitoneal route was toxic to rats (120-125 g body weight) and caused death within 24 hour while lectins extracted from irradiated beans showed no lethal effect. Administration of 28% raw beans diet as the sole protein in balanced diet caused strong growth depression in young rats. Radiation treatment corrects poor growth but did not prevent liver and stomach hypertrophy. No significant differences in relative organs body weight, between groups fed irradiated soybeans and casein diet were observed, except for an increased relative lever and stomach weights with group fed irradiated beans. Rats which received raw beans in their diet suffered from pancreatic, liver, stomach, testes and kidney hypertrophy and spleen atrophy. Data obtained on certain blood plasma chemical constituents (total plasma protein creatine, creatinine) revealed no significant difference between the control and experimental groups. 4 tabs

  20. Lysophosphatidic acid stimulates thrombomodulin lectin-like domain shedding in human endothelial cells

    International Nuclear Information System (INIS)

    Wu Hualin; Lin ChiIou; Huang Yuanli; Chen, Pin-Shern; Kuo, Cheng-Hsiang; Chen, Mei-Shing; Wu, G.C.-C.; Shi, G.-Y.; Yang, H.-Y.; Lee Hsinyu

    2008-01-01

    Thrombomodulin (TM) is an anticoagulant glycoprotein highly expressed on endothelial cell surfaces. Increased levels of soluble TM in circulation have been widely accepted as an indicator of endothelial damage or dysfunction. Previous studies indicated that various proinflammatory factors stimulate TM shedding in various cell types such as smooth muscle cells and epithelial cells. Lysophosphatidic acid (LPA) is a bioactive lipid mediator present in biological fluids during endothelial damage or injury. In the present study, we first observed that LPA triggered TM shedding in human umbilical vein endothelial cells (HUVECs). By Cyflow analysis, we showed that the LPA-induced accessibility of antibodies to the endothelial growth factor (EGF)-like domain of TM is independent of matrix metalloproteinases (MMPs), while LPA-induced TM lectin-like domain shedding is MMP-dependent. Furthermore, a stable cell line expressing TM without its lectin-like domain exhibited a higher cell proliferation rate than a stable cell line expressing full-length TM. These results imply that LPA induces TM lectin-like domain shedding, which might contribute to the exposure of its EGF-like domain for EGF receptor (EGFR) binding, thereby stimulating subsequent cell proliferation. Based on our findings, we propose a novel mechanism for the exposure of TM EGF-like domain, which possibly mediates LPA-induced EGFR transactivation

  1. Dyslexic Children Show Atypical Cerebellar Activation and Cerebro-Cerebellar Functional Connectivity in Orthographic and Phonological Processing.

    Science.gov (United States)

    Feng, Xiaoxia; Li, Le; Zhang, Manli; Yang, Xiujie; Tian, Mengyu; Xie, Weiyi; Lu, Yao; Liu, Li; Bélanger, Nathalie N; Meng, Xiangzhi; Ding, Guosheng

    2017-04-01

    Previous neuroimaging studies have found atypical cerebellar activation in individuals with dyslexia in either motor-related tasks or language tasks. However, studies investigating atypical cerebellar activation in individuals with dyslexia have mostly used tasks tapping phonological processing. A question that is yet unanswered is whether the cerebellum in individuals with dyslexia functions properly during orthographic processing of words, as growing evidence shows that the cerebellum is also involved in visual and spatial processing. Here, we investigated cerebellar activation and cerebro-cerebellar functional connectivity during word processing in dyslexic readers and typically developing readers using tasks that tap orthographic and phonological codes. In children with dyslexia, we observed an abnormally higher engagement of the bilateral cerebellum for the orthographic task, which was negatively correlated with literacy measures. The greater the reading impairment was for young dyslexic readers, the stronger the cerebellar activation was. This suggests a compensatory role of the cerebellum in reading for children with dyslexia. In addition, a tendency for higher cerebellar activation in dyslexic readers was found in the phonological task. Moreover, the functional connectivity was stronger for dyslexic readers relative to typically developing readers between the lobule VI of the right cerebellum and the left fusiform gyrus during the orthographic task and between the lobule VI of the left cerebellum and the left supramarginal gyrus during the phonological task. This pattern of results suggests that the cerebellum compensates for reading impairment through the connections with specific brain regions responsible for the ongoing reading task. These findings enhance our understanding of the cerebellum's involvement in reading and reading impairment.

  2. Rosmarinic Acid from Eelgrass Shows Nematicidal and Antibacterial Activities against Pine Wood Nematode and Its Carrying Bacteria

    Directory of Open Access Journals (Sweden)

    Qunqun Guo

    2012-11-01

    Full Text Available Pine wilt disease (PWD, a destructive disease for pine trees, is caused by the pine wood nematode (PWN, Bursaphelenchus xylophilus and additional bacteria. In this study, extracts of Zostera marina showed a high nematicidal activity against PWN and some of the bacteria that it carries. Light yellow crystals were obtained from extracts of Z. marina through solvent extraction, followed by chromatography on AB-8 resin and crystallization. The NMR and HPLC analysis showed that the isolated compound was rosmarinic acid (RosA. RosA showed effective nematicidal activity, of which the LC50 (50% lethal concentration to PWN at 24 h, 48 h and 72 h was 1.18 mg/g, 1.05 mg/g and 0.95 mg/g, respectively. To get a high yield rate of RosA from Z. marina, single factor experiments and an L9 (34 orthogonal experiment were performed. This extraction process involved 70% ethanol for 3 h at 40 °C. The extraction dosage was 1:50 (w/v. The highest yield of RosA from Zostera was 3.13 mg/g DW (dried weight. The crude extracts of Zostera marina (10 mg/mL and RosA (1 mg/mL also showed inhibitory effects to some bacterial strains carried by PWN: Klebsiella sp., Stenotrophomonas maltophilia, Streptomyces sp. and Pantoea agglomerans. The results of these studies provide clues for preparing pesticide to control PWD from Z. marina.

  3. Direct analysis of the lectin reactivity of alpha-fetoprotein in maternal serum by crossed affinity radio-immunoelectrophoresis

    International Nuclear Information System (INIS)

    Kerckaert, J.P.; Bayard, B.; Biserte, G.; Puech, F.; Codaccioni, X.

    1980-01-01

    Affinity experiments with the lentil (Lens culinaris) lectin have revealed the existence of two distinct molecular populations of alpha-fetoprotein: lectin reactive and lectin non-reactive. Using a combination of crossed lectin immunoelectrophoresis and radio-immunoelectrophoresis, it has been possible to obtain directly the lentil lectin affinity patterns of alpha-fetoprotein present in maternal sera. The lentil lectin reactivity of maternal alpha-fetoprotein decreases almost linearly with the gestational age from week 15 to 35. (Auth.)

  4. Seizures and Sleep in the Thalamus: Focal Limbic Seizures Show Divergent Activity Patterns in Different Thalamic Nuclei.

    Science.gov (United States)

    Feng, Li; Motelow, Joshua E; Ma, Chanthia; Biche, William; McCafferty, Cian; Smith, Nicholas; Liu, Mengran; Zhan, Qiong; Jia, Ruonan; Xiao, Bo; Duque, Alvaro; Blumenfeld, Hal

    2017-11-22

    The thalamus plays diverse roles in cortical-subcortical brain activity patterns. Recent work suggests that focal temporal lobe seizures depress subcortical arousal systems and convert cortical activity into a pattern resembling slow-wave sleep. The potential simultaneous and paradoxical role of the thalamus in both limbic seizure propagation, and in sleep-like cortical rhythms has not been investigated. We recorded neuronal activity from the central lateral (CL), anterior (ANT), and ventral posteromedial (VPM) nuclei of the thalamus in an established female rat model of focal limbic seizures. We found that population firing of neurons in CL decreased during seizures while the cortex exhibited slow waves. In contrast, ANT showed a trend toward increased neuronal firing compatible with polyspike seizure discharges seen in the hippocampus. Meanwhile, VPM exhibited a remarkable increase in sleep spindles during focal seizures. Single-unit juxtacellular recordings from CL demonstrated reduced overall firing rates, but a switch in firing pattern from single spikes to burst firing during seizures. These findings suggest that different thalamic nuclei play very different roles in focal limbic seizures. While limbic nuclei, such as ANT, appear to participate directly in seizure propagation, arousal nuclei, such as CL, may contribute to depressed cortical function, whereas sleep spindles in relay nuclei, such as VPM, may interrupt thalamocortical information flow. These combined effects could be critical for controlling both seizure severity and impairment of consciousness. Further understanding of differential effects of seizures on different thalamocortical networks may lead to improved treatments directly targeting these modes of impaired function. SIGNIFICANCE STATEMENT Temporal lobe epilepsy has a major negative impact on quality of life. Previous work suggests that the thalamus plays a critical role in thalamocortical network modulation and subcortical arousal

  5. Origanum vulgare subsp. hirtum essential oil prevented biofilm formation and showed antibacterial activity against planktonic and sessile bacterial cells.

    Science.gov (United States)

    Schillaci, Domenico; Napoli, Edoardo Marco; Cusimano, Maria Grazia; Vitale, Maria; Ruberto, Andgiuseppe

    2013-10-01

    Essential oils from six different populations of Origanum vulgare subsp. hirtum were compared for their antibiofilm properties. The six essential oils (A to F) were characterized by a combination of gas chromatography with flame ionization detector and gas chromatography with mass spectrometer detector analyses. All oils showed weak activity against the planktonic form of a group of Staphylococcus aureus strains and against a Pseudomonas aeruginosa ATCC 15442 reference strain. The ability to inhibit biofilm formation was investigated at sub-MIC levels of 200, 100, and 50 m g/ml by staining sessile cells with safranin. Sample E showed the highest average effectiveness against all tested strains at 50 m g/ml and had inhibition percentages ranging from 30 to 52%. In the screening that used preformed biofilm from the reference strain P. aeruginosa, essential oils A through E were inactive at 200 m g/ml; F was active with a percentage of inhibition equal to 53.2%. Oregano essential oil can inhibit the formation of biofilms of various food pathogens and food spoilage organisms.

  6. A label-free fluorescence biosensor for highly sensitive detection of lectin based on carboxymethyl chitosan-quantum dots and gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ziping; Liu, Hua; Wang, Lei; Su, Xingguang, E-mail: suxg@jlu.edu.cn

    2016-08-17

    inner filter effect of Au NPs on CM-CHIT-QDs. • Lectin could bind exclusively to CM-CHIT-QDs via multivalent carbohydrate-protein interactions, and “turn on” the fluorescence. • The biosensor sensor showed good selectivity for the detection of lectin with a low detection limit of 0.07 nM.

  7. A label-free fluorescence biosensor for highly sensitive detection of lectin based on carboxymethyl chitosan-quantum dots and gold nanoparticles

    International Nuclear Information System (INIS)

    Liu, Ziping; Liu, Hua; Wang, Lei; Su, Xingguang

    2016-01-01

    -CHIT-QDs. • Lectin could bind exclusively to CM-CHIT-QDs via multivalent carbohydrate-protein interactions, and “turn on” the fluorescence. • The biosensor sensor showed good selectivity for the detection of lectin with a low detection limit of 0.07 nM.

  8. Association between lectin complement pathway initiators, C-reactive protein and left ventricular remodeling in myocardial infarction-a magnetic resonance study

    DEFF Research Database (Denmark)

    Schoos, Mikkel Malby; Munthe-Fog, Lea; Skjoedt, Mikkel-Ole

    2013-01-01

    Lectin complement pathway (LP) activation is an important mechanism in myocardial ischemia reperfusion injury (IRI). LP is activated via the recognition molecules mannose-binding lectin (MBL), ficolins-2 and-3 and is regulated by MBL/Ficolin-associated Protein-1 (MAP-1). Also, C-reactive protein...... (CRP) and ficolin-2 interact in vitro, but the role of the ficolins in IRI is unknown.Methods and results In 55 patients with ST segment elevation myocardial infarction, we investigated the association of LP components and CRP in plasma samples with left ventricular (LV) end systolic and diastolic......-activation in IRI and LV remodeling....

  9. Comparison of the antimicrobial adhesion potential of human body fluid glycoconjugates using fucose-binding lectin (PA-IIL) of Pseudomonas aeruginosa and Ulex europaeus lectin (UEA-I).

    Science.gov (United States)

    Lerrer, Batia; Lesman-Movshovich, Efrat; Gilboa-Garber, Nechama

    2005-09-01

    Pseudomonas aeruginosa produces a fucose-binding lectin (PA-IIL) which strongly binds to human cells. This lectin was shown to be highly sensitive to inhibition by fucose-bearing human milk glycoproteins. Since the glycans of these glycoproteins mimic human cell receptors, they may function as decoys in blocking lectin-dependent pathogen adhesion to the host cells. Human saliva and seminal fluid also contain such compounds, and body fluids of individuals who are "secretors" express additional fucosylated (alpha 1,2) residues. The latter are selectively detected by Ulex europaeus lectin UEA-I. The aim of the present research was to compare the PA-IIL and UEA-I interactions with human salivas and seminal fluids of "secretors" and "nonsecretors" with those obtained with the respective milks. Using hemagglutination inhibition and Western blot analyses, we showed that PA-IIL interactions with the saliva and seminal fluid glycoproteins were somewhat weaker than those obtained with the milk and that "nonsecretor" body fluids were not less efficient than those of "secretors" in PA-IIL blocking. UEA-I, which interacted only with the "secretors" glycoproteins, was most sensitive to those of the seminal fluids.

  10. Rescuing Alu: recovery of new inserts shows LINE-1 preserves Alu activity through A-tail expansion.

    Directory of Open Access Journals (Sweden)

    Bradley J Wagstaff

    Full Text Available Alu elements are trans-mobilized by the autonomous non-LTR retroelement, LINE-1 (L1. Alu-induced insertion mutagenesis contributes to about 0.1% human genetic disease and is responsible for the majority of the documented instances of human retroelement insertion-induced disease. Here we introduce a SINE recovery method that provides a complementary approach for comprehensive analysis of the impact and biological mechanisms of Alu retrotransposition. Using this approach, we recovered 226 de novo tagged Alu inserts in HeLa cells. Our analysis reveals that in human cells marked Alu inserts driven by either exogenously supplied full length L1 or ORF2 protein are indistinguishable. Four percent of de novo Alu inserts were associated with genomic deletions and rearrangements and lacked the hallmarks of retrotransposition. In contrast to L1 inserts, 5' truncations of Alu inserts are rare, as most of the recovered inserts (96.5% are full length. De novo Alus show a random pattern of insertion across chromosomes, but further characterization revealed an Alu insertion bias exists favoring insertion near other SINEs, highly conserved elements, with almost 60% landing within genes. De novo Alu inserts show no evidence of RNA editing. Priming for reverse transcription rarely occurred within the first 20 bp (most 5' of the A-tail. The A-tails of recovered inserts show significant expansion, with many at least doubling in length. Sequence manipulation of the construct led to the demonstration that the A-tail expansion likely occurs during insertion due to slippage by the L1 ORF2 protein. We postulate that the A-tail expansion directly impacts Alu evolution by reintroducing new active source elements to counteract the natural loss of active Alus and minimizing Alu extinction.

  11. Indonesian Fire Activity and Smoke Pollution in 2015 Show Persistent Nonlinear Sensitivity to El Niño-induced Drought

    Science.gov (United States)

    Field, Robert D.; van der Werf, Guido R.; Fanin, Thierry; Fetzer, Eric; Fuller, Ryan; Jethva, Hiren; Levy, Robert; Livesey, Nathaniel; Luo, Ming; Torres, Omar; hide

    2016-01-01

    The 2015 fire season and related smoke pollution in Indonesia was more severe than the major 2006 episode, making it the most severe season observed by the NASA Earth Observing System satellites that go back to the early 2000s, namely active fire detections from the Terra and Aqua Moderate Resolution Imaging Spectroradiometers (MODIS), MODIS aerosol optical depth, Terra Measurement of Pollution in the Troposphere (MOPITT) carbon monoxide (CO), Aqua Atmospheric Infrared Sounder (AIRS) CO, Aura Ozone Monitoring Instrument (OMI) aerosol index, and Aura Microwave Limb Sounder (MLS) CO. The MLS CO in the upper troposphere showed a plume of pollution stretching from East Africa to the western Pacific Ocean that persisted for two months. Longer-term records of airport visibility in Sumatra and Kalimantan show that 2015 ranked after 1997 and alongside 1991 and 1994 as among the worst episodes on record. Analysis of yearly dry season rainfall from the Tropical Rainfall Measurement Mission (TRMM) and rain gauges shows that, due to the continued use of fire to clear and prepare land on degraded peat, the Indonesian fire environment continues to have non-linear sensitivity to dry conditions during prolonged periods with less than 4mmday of precipitation, and this sensitivity appears to have increased over Kalimantan. Without significant reforms in land use and the adoption of early warning triggers tied to precipitation forecasts, these intense fire episodes will re-occur during future droughts, usually associated with El Nio events.

  12. Coadministration of doxorubicin and etoposide loaded in camel milk phospholipids liposomes showed increased antitumor activity in a murine model

    Directory of Open Access Journals (Sweden)

    Maswadeh HM

    2015-04-01

    Full Text Available Hamzah M Maswadeh,1 Ahmed N Aljarbou,1 Mohammed S Alorainy,2 Arshad H Rahmani,3 Masood A Khan3 1Department of Pharmaceutics, College of Pharmacy, 2Department of Pharmacology and Therapeutics, College of Medicine, 3College of Applied Medical Sciences, Qassim University, Buraydah, Kingdom of Saudi Arabia Abstract: Small unilamellar vesicles from camel milk phospholipids (CML mixture or from 1,2 dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC were prepared, and anticancer drugs doxorubicin (Dox or etoposide (ETP were loaded. Liposomal formulations were used against fibrosarcoma in a murine model. Results showed a very high percentage of Dox encapsulation (~98% in liposomes (Lip prepared from CML-Lip or DPPC-Lip, whereas the percentage of encapsulations of ETP was on the lower side, 22% of CML-Lip and 18% for DPPC-Lip. Differential scanning calorimetry curves show that Dox enhances the lamellar formation in CML-Lip, whereas ETP enhances the nonlamellar formation. Differential scanning calorimetry curves also showed that the presence of Dox and ETP together into DPPC-Lip produced the interdigitation effect. The in vivo anticancer activity of liposomal formulations of Dox or ETP or a combination of both was assessed against benzopyrene (BAP-induced fibrosarcoma in a murine model. Tumor-bearing mice treated with a combination of Dox and ETP loaded into CML-Lip showed increased survival and reduced tumor growth compared to other groups, including the combination of Dox and ETP in DPPC-Lip. Fibrosarcoma-bearing mice treated with a combination of free (Dox + ETP showed much higher tumor growth compared to those groups treated with CML-Lip-(Dox + ETP or DPPC-Lip-(Dox + ETP. Immunohistochemical study was also performed to show the expression of tumor-suppressor PTEN, and it was found that the tumor tissues from the group of mice treated with a combination of free (Dox + ETP showed greater loss of cytoplasmic PTEN than tumor tissues obtained from the

  13. Intrinsic atopic dermatitis shows similar TH2 and higher TH17 immune activation compared with extrinsic atopic dermatitis.

    Science.gov (United States)

    Suárez-Fariñas, Mayte; Dhingra, Nikhil; Gittler, Julia; Shemer, Avner; Cardinale, Irma; de Guzman Strong, Cristina; Krueger, James G; Guttman-Yassky, Emma

    2013-08-01

    Atopic dermatitis (AD) is classified as extrinsic and intrinsic, representing approximately 80% and 20% of patients with the disease, respectively. Although sharing a similar clinical phenotype, only extrinsic AD is characterized by high serum IgE levels. Because most patients with AD exhibit high IgE levels, an "allergic"/IgE-mediated disease pathogenesis was hypothesized. However, current models associate AD with T-cell activation, particularly TH2/TH22 polarization, and epidermal barrier defects. We sought to define whether both variants share a common pathogenesis. We stratified 51 patients with severe AD into extrinsic AD (n = 42) and intrinsic AD (n = 9) groups (with similar mean disease activity/SCORAD scores) and analyzed the molecular and cellular skin pathology of lesional and nonlesional intrinsic AD and extrinsic AD by using gene expression (real-time PCR) and immunohistochemistry. A significant correlation between IgE levels and SCORAD scores (r = 0.76, P extrinsic AD. Marked infiltrates of T cells and dendritic cells and corresponding epidermal alterations (keratin 16, Mki67, and S100A7/A8/A9) defined lesional skin of patients with both variants. However, higher activation of all inflammatory axes (including TH2) was detected in patients with intrinsic AD, particularly TH17 and TH22 cytokines. Positive correlations between TH17-related molecules and SCORAD scores were only found in patients with intrinsic AD, whereas only patients with extrinsic AD showed positive correlations between SCORAD scores and TH2 cytokine (IL-4 and IL-5) levels and negative correlations with differentiation products (loricrin and periplakin). Although differences in TH17 and TH22 activation exist between patients with intrinsic AD and those with extrinsic AD, we identified common disease-defining features of T-cell activation, production of polarized cytokines, and keratinocyte responses to immune products. Our data indicate that a TH2 bias is not the sole cause of high Ig

  14. Fusion of protegrin-1 and plectasin to MAP30 shows significant inhibition activity against dengue virus replication.

    Directory of Open Access Journals (Sweden)

    Hussin A Rothan

    Full Text Available Dengue virus (DENV broadly disseminates in tropical and sub-tropical countries and there are no vaccine or anti-dengue drugs available. DENV outbreaks cause serious economic burden due to infection complications that requires special medical care and hospitalization. This study presents a new strategy for inexpensive production of anti-DENV peptide-fusion protein to prevent and/or treat DENV infection. Antiviral cationic peptides protegrin-1 (PG1 and plectasin (PLSN were fused with MAP30 protein to produce recombinant antiviral peptide-fusion protein (PG1-MAP30-PLSN as inclusion bodies in E. coli. High yield production of PG1-MAP30-PLSN protein was achieved by solubilization of inclusion bodies in alkaline buffer followed by the application of appropriate refolding techniques. Antiviral PG1-MAP30-PLSN protein considerably inhibited DENV protease (NS2B-NS3pro with half-maximal inhibitory concentration (IC50 0.5±0.1 μM. The real-time proliferation assay (RTCA and the end-point proliferation assay (MTT assay showed that the maximal-nontoxic dose of the peptide-fusion protein against Vero cells is approximately 0.67±0.2 μM. The cell-based assays showed considerable inhibition of the peptide-fusion protein against binding and proliferating stages of DENV2 into the target cells. The peptide-fusion protein protected DENV2-challeged mice with 100% of survival at the dose of 50 mg/kg. In conclusion, producing recombinant antiviral peptide-fusion protein by combining short antiviral peptide with a central protein owning similar activity could be useful to minimize the overall cost of short peptide production and take advantage of its synergistic antiviral activities.

  15. Antifungal activity of secondary plant metabolites from potatoes (Solanum tuberosum L.): Glycoalkaloids and phenolic acids show synergistic effects.

    Science.gov (United States)

    Sánchez-Maldonado, A F; Schieber, A; Gänzle, M G

    2016-04-01

    To study the antifungal effects of the potato secondary metabolites α-solanine, α-chaconine, solanidine and caffeic acid, alone or combined. Resistance to glycoalkaloids varied among the fungal species tested, as derived from minimum inhibitory concentrations assays. Synergistic antifungal activity between glycoalkaloids and phenolic compounds was found. Changes in the fluidity of fungal membranes caused by potato secondary plant metabolites were determined by calculation of the generalized polarization values. The results partially explained the synergistic effect between caffeic acid and α-chaconine and supported findings on membrane disruption mechanisms from previous studies on artificial membranes. LC/MS analysis was used to determine variability and relative amounts of sterols in the different fungal species. Results suggested that the sterol pattern of fungi is related to their resistance to potato glycoalkaloids and to their taxonomy. Fungal resistance to α-chaconine and possibly other glycoalkaloids is species dependent. α-Chaconine and caffeic acid show synergistic antifungal activity. The taxonomic classification and the sterol pattern play a role in fungal resistance to glycoalkaloids. Results improve the understanding of the antifungal mode of action of potato secondary metabolites, which is essential for their potential utilization as antifungal agents in nonfood systems. © 2016 The Society for Applied Microbiology.

  16. Transcriptome analysis shows activation of the arginine deiminase pathway in Lactococcus lactis as a response to ethanol stress.

    Science.gov (United States)

    Díez, Lorena; Solopova, Ana; Fernández-Pérez, Rocío; González, Miriam; Tenorio, Carmen; Kuipers, Oscar P; Ruiz-Larrea, Fernanda

    2017-09-18

    This paper describes the molecular response of Lactococcus lactis NZ9700 to ethanol. This strain is a well-known nisin producer and a lactic acid bacteria (LAB) model strain. Global transcriptome profiling using DNA microarrays demonstrated a bacterial adaptive response to the presence of 2% ethanol in the culture broth and differential expression of 67 genes. The highest up-regulation was detected for those genes involved in arginine degradation through the arginine deiminase (ADI) pathway (20-40 fold up-regulation). The metabolic responses to ethanol of wild type L. lactis strains were studied and compared to those of regulator-deletion mutants MG∆argR and MG∆ahrC. The results showed that in the presence of 2% ethanol those strains with an active ADI pathway reached higher growth rates when arginine was available in the culture broth than in absence of arginine. In a chemically defined medium strains with an active ADI pathway consumed arginine and produced ornithine in the presence of 2% ethanol, hence corroborating that arginine catabolism is involved in the bacterial response to ethanol. This is the first study of the L. lactis response to ethanol stress to demonstrate the relevance of arginine catabolism for bacterial adaptation and survival in an ethanol containing medium. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Akinetic-rigid and tremor-dominant Parkinson's disease patients show different patterns of intrinsic brain activity.

    Science.gov (United States)

    Zhang, Jiuquan; Wei, Luqing; Hu, Xiaofei; Xie, Bing; Zhang, Yanling; Wu, Guo-Rong; Wang, Jian

    2015-01-01

    Parkinson's disease (PD) is a surprisingly heterogeneous neurodegenerative disorder. It is well established that different subtypes of PD present with different clinical courses and prognoses. However, the neural mechanism underlying these disparate presentations is uncertain. Here we used resting-state fMRI (rs-fMRI) and the regional homogeneity (ReHo) method to determine neural activity patterns in the two main clinical subgroups of PD (akinetic-rigid and tremor-dominant). Compared with healthy controls, akinetic-rigid (AR) subjects had increased ReHo mainly in right amygdala, left putamen, bilateral angular gyrus, bilateral medial prefrontal cortex (MPFC), and decreased ReHo in left post cingulate gyrus/precuneus (PCC/PCu) and bilateral thalamus. In contrast, tremor-dominant (TD) patients showed higher ReHo mostly in bilateral angular gyrus, left PCC, cerebellum_crus1, and cerebellum_6, while ReHo was decreased in right putamen, primary sensory cortex (S1), vermis_3, and cerebellum_4_5. These results indicate that AR and TD subgroups both represent altered spontaneous neural activity in default-mode regions and striatum, and AR subjects exhibit more changed neural activity in the mesolimbic cortex (amygdala) but TD in the cerebellar regions. Of note, direct comparison of the two subgroups revealed a distinct ReHo pattern primarily located in the striatal-thalamo-cortical (STC) and cerebello-thalamo-cortical (CTC) loops. Overall, our findings highlight the involvement of default mode network (DMN) and STC circuit both in AR and TD subtypes, but also underscore the importance of integrating mesolimbic-striatal and CTC loops in understanding neural systems of akinesia and rigidity, as well as resting tremor in PD. This study provides improved understanding of the pathophysiological models of different subtypes of PD. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Overexpression of Nictaba-Like Lectin Genes from Glycine max Confers Tolerance towards Pseudomonas syringae Infection, Aphid Infestation and Salt Stress in Transgenic Arabidopsis Plants

    Directory of Open Access Journals (Sweden)

    Sofie Van Holle

    2016-10-01

    Full Text Available Plants have evolved a sophisticated immune system that allows them to recognize invading pathogens by specialized receptors. Carbohydrate-binding proteins or lectins are part of this immune system and especially the lectins that reside in the nucleocytoplasmic compartment are known to be implicated in biotic and abiotic stress responses. The class of Nictaba-like lectins (NLL groups all proteins with homology to the tobacco (Nicotiana tabacum lectin, known as a stress-inducible lectin. Here we focus on two Nictaba homologs from soybean (Glycine max, referred to as GmNLL1 and GmNLL2. Confocal laser scanning microscopy of fusion constructs with the green fluorescent protein either transiently expressed in Nicotiana benthamiana leaves or stably transformed in tobacco BY-2 suspension cells revealed a nucleocytoplasmic localization for the GmNLLs under study. RT-qPCR analysis of the transcript levels for the Nictaba-like lectins in soybean demonstrated that the genes are expressed in several tissues throughout the development of the plant. Furthermore, it was shown that salt treatment, Phytophthora sojae infection and Aphis glycines infestation trigger the expression of particular NLL genes. Stress experiments with Arabidopsis lines overexpressing the NLLs from soybean yielded an enhanced tolerance of the plant towards bacterial infection (Pseudomonas syringae, insect infestation (Myzus persicae and salinity. Our data showed a better performance of the transgenic lines compared to wild type plants, indicating that the NLLs from soybean are implicated in the stress response. These data can help to further elucidate the physiological importance of the Nictaba-like lectins from soybean, which can ultimately lead to the design of crop plants with a better tolerance to changing environmental conditions.

  19. Mistletoe lectin I in complex with galactose and lactose reveals distinct sugar-binding properties

    International Nuclear Information System (INIS)

    Mikeska, Ruth; Wacker, Roland; Arni, Raghuvir; Singh, Tej P.; Mikhailov, Albert; Gabdoulkhakov, Azat; Voelter, Wolfgang; Betzel, Christian

    2004-01-01

    The structures of mistletoe lectin I in complex with lactose and galactose reveal differences in binding by the two known sites in subdomains α1 and γ2 and suggest the presence of a third low-affinity site in subdomain β1. The structures of mistletoe lectin I (ML-I) from Viscum album complexed with lactose and galactose have been determined at 2.3 Å resolution and refined to R factors of 20.9% (R free = 23.6%) and 20.9 (R free = 24.6%), respectively. ML-I is a heterodimer and belongs to the class of ribosome-inactivating proteins of type II, which consist of two chains. The A-chain has rRNA N-glycosidase activity and irreversibly inhibits eukaryotic ribosomes. The B-chain is a lectin and preferentially binds to galactose-terminated glycolipids and glycoproteins on cell membranes. Saccharide binding is performed by two binding sites in subdomains α1 and γ2 of the ML-I B-chain separated by ∼62 Å from each other. The favoured binding of galactose in subdomain α1 is achieved via hydrogen bonds connecting the 4-hydroxyl and 3-hydroxyl groups of the sugar moiety with the side chains of Asp23B, Gln36B and Lys41B and the main chain of 26B. The aromatic ring of Trp38B on top of the preferred binding pocket supports van der Waals packing of the apolar face of galactose and stabilizes the sugar–lectin complex. In the galactose-binding site II of subdomain γ2, Tyr249B provides the hydrophobic stacking and the side chains of Asp235B, Gln238B and Asn256B are hydrogen-bonding partners for galactose. In the case of the galactose-binding site I, the 2-hydroxyl group also stabilizes the sugar–protein complex, an interaction thus far rarely detected in galactose-specific lectins. Finally, a potential third low-affinity galactose-binding site in subunit β1 was identified in the present ML-I structures, in which a glycerol molecule from the cryoprotectant buffer has bound, mimicking the sugar compound

  20. Tear fluid analysis in patients with primary Sjögren's syndrome using lectin probes

    DEFF Research Database (Denmark)

    Bjerrum, Kirsten Birgitte

    1999-01-01

    Ophthalmology, Sjögren's syndrome, dry eye, keratoconjunctivitis sicca, glycoprotein, mucus, lectins, Coomassie, electrophoresis, SDS-PAGE-blotting......Ophthalmology, Sjögren's syndrome, dry eye, keratoconjunctivitis sicca, glycoprotein, mucus, lectins, Coomassie, electrophoresis, SDS-PAGE-blotting...

  1. Mannan-Binding Lectin in Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Izabela Pągowska-Klimek

    2014-01-01

    Full Text Available Cardiovascular disease remains the leading cause of mortality and morbidity worldwide so research continues into underlying mechanisms. Since innate immunity and its potent component mannan-binding lectin have been proven to play an important role in the inflammatory response during infection and ischaemia-reperfusion injury, attention has been paid to its role in the development of cardiovascular complications as well. This review provides a general outline of the structure and genetic polymorphism of MBL and its role in inflammation/tissue injury with emphasis on associations with cardiovascular disease. MBL appears to be involved in the pathogenesis of atherosclerosis and, in consequence, coronary artery disease and also inflammation and tissue injury after myocardial infarction and heart transplantation. The relationship between MBL and disease is rather complex and depends on different genetic and environmental factors. That could be why the data obtained from animal and clinical studies are sometimes contradictory proving not for the first time that innate immunity is a “double-edge sword,” sometimes beneficial and, at other times disastrous for the host.

  2. Lectin I from Bauhinia variegata (BVL-I) expressed by Pichia pastoris inhibits initial adhesion of oral bacteria in vitro.

    Science.gov (United States)

    Klafke, Gabriel Baracy; Moreira, Gustavo Marçal Schmidt Garcia; Pereira, Juliano Lacava; Oliveira, Patrícia Diaz; Conceição, Fabricio Rochedo; Lund, Rafael Guerra; Grassmann, André Alex; Dellagostin, Odir Antonio; da Silva Pinto, Luciano

    2016-12-01

    Lectins are non-immune proteins that reversibly bind to carbohydrates in a specific manner. Bauhinia variegata lectin I (BVL-I) is a Gal/GalNAc-specific, single-chain lectin isolated from Bauhinia variegata seeds that has been implicated in the inhibition of bacterial adhesion and the healing of damaged skin. Since the source of the native protein (nBVL) is limited, this study aimed to produce recombinant BVL-I in Pichia pastoris (rBVL-Ip). The coding sequence for BVL-I containing preferential codons for P. pastoris was cloned into the pPICZαB plasmid. A single expressing clone was selected and fermented, resulting in the secretion and glycosylation of the protein. Fed-batch fermentation in 7L-scale was performed, and the recombinant lectin was purified from culture supernatant, resulting in a yield of 1.5mg/L culture. Further, rBVL-Ip was compared to nBVL and its recombinant version expressed in Escherichia coli BL21 (DE3) (rBVL-Ie). Although it was expressed as a monomer, rBVL-Ip retained its biological activity since it was able to impair the initial adhesion of Streptococcus mutans and S. sanguinis in an in vitro model of biofilm formation and bacterial adhesion. In summary, rBVL-Ip produced in Pichia pastoris represents a viable alternative to large-scale production, encouraging further biological application studies with this lectin. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Population heterogeneity in the surface expression of Ulex europaeus I-lectin (UEA I)-binding sites in cultured malignant and transformed cells

    Energy Technology Data Exchange (ETDEWEB)

    Virtanen, I.; Lehtonen, E.; Naervaenen, O.; Leivo, I.; Lehto, V.P.

    1985-11-01

    We studied the binding of fluorochrome-coupled Ulex europaeus I-lectin (UEA-I) to cultured malignant cells: all human malignant and transformed cells and also mouse teratocarcinoma cells examined gave a homogeneous cell membrane-type of surface staining only in some of the cells. Such a population heterogeneity appeared to be independent of the cell cycle. Instead, other lectin conjugates used bound homogeneously to all cell. In permeabilized cells, a juxtanuclear reticular staining of the Golgi apparatus was seen in the UEA-I-positive cells. No staining of the pericellular matrix components, produced by malignant cells grown in serum-free culture medium, could be obtained with TRITC-UEA-I. UEA-I-lectin recognized most polypeptides from A8387 fibrosarcoma cells and HeLa cells, metabolically labelled with (/sup 3/H)fucose. Furthermore, surface labelling of these cells with the neuraminidase-galactose oxidase/sodium borohydride method disclosed that both UEA-I and Ricinus communis agglutinin I revealed the same major surface glycoproteins. Results with metabolically labelled cells showed, in addition, that UEA-I-lectin did not bind to secreted glycoproteins produced by A8387 cells and recognized by other lectins. The results indicate that transformed and malignant cells show a distinct population heterogeneity in their expression of some cell surface-associated fucosyl glycoconjugates. The results also suggest that malignant cells can glycosylate their membrane and secreted glycoproteins in a different manner.

  4. A Computational analysis on Lectin and Histone H1 protein of different pulse species as well as comparative study with rice for balanced diet.

    Science.gov (United States)

    Hasan, Md Anayet; Mannan, Adnan; Alam, Rashel; Islam, Md Taohidul; Amin, Mohammad Al; Khan, Md Sarowar Jahan; Islam, Md Ashraful; Muzahid, Nazmul Hasan

    2012-01-01

    The issue of balanced nutrition is of great concern to human. Meat and fish are the best sources of protein. The affordability of these resources for people in developing countries is less. Thus, there is an increasing interest in pulses and its derivates as an alternative to fish and meat. Lectin and histone H1 are the most common proteins in various pulses and our interest is in identifying the dominant essential amino acids in them for use as supplements. However, actin and lectin are common among Oryza Sativa and cicer arietinum. We describe the amount of lectin and histone H1 in cicer arietinum, Lens culinaris and Pisum sativum in a comparative manner. cicer arietinum was found to contain more essential amino acids than Lens culinaris and Pisum sativum. The secondary structures of lectin and histone H1 protein were analyzed to gain functional inferences in these species. The comparative study shows the relatively poor presence of the amino acid methionine in most pulses. However, Oryza Sativa was found to contain sufficient methionine. The study shows that pulses (especially cicer arietinum) were a suitable alternative source to meat and fish for Lectin and Histone H1 balance. Hence, pulses could be suggested with rice for balanced protein diet.

  5. Lectins binding during alloxan-induced diabetes in rat soleus muscle

    African Journals Online (AJOL)

    Membrane structural changes of soleus muscle of alloxan-diabetic rats were detected with a panel of six biotinylated lectins. Samples of muscles were obtained from normal and diabetic rats. The biotinylated lectins in staining were detected by avidin-peroxidase complex. Lectin stainning of soleus muscle cryostat sections ...

  6. One Size Does Not Fit All: Contextualising Family Physical Activity Using a Write, Draw, Show and Tell Approach.

    Science.gov (United States)

    Noonan, Robert J; Fairclough, Stuart J; Knowles, Zoe R; Boddy, Lynne M

    2017-07-14

    Understanding family physical activity (PA) behaviour is essential for designing effective family-based PA interventions. However, effective approaches to capture the perceptions and "lived experiences" of families are not yet well established. The aims of the study were to: (1) demonstrate how a "write, draw, show and tell" (WDST) methodological approach can be appropriate to family-based PA research, and (2) present two distinct family case studies to provide insights into the habitual PA behaviour and experiences of a nuclear and single-parent family. Six participants (including two "target" children aged 9-11 years, two mothers and two siblings aged 6-8 years) from two families were purposefully selected to take part in the study, based on their family structure. Participants completed a paper-based PA diary and wore an ActiGraph GT9X accelerometer on their left wrist for up to 10 weekdays and 16 weekend days. A range of WDST tasks were then undertaken by each family to offer contextual insight into their family-based PA. The selected families participated in different levels and modes of PA, and reported contrasting leisure opportunities and experiences. These novel findings encourage researchers to tailor family-based PA intervention programmes to the characteristics of the family.

  7. The temperate Burkholderia phage AP3 of the Peduovirinae shows efficient antimicrobial activity against B. cenocepacia of the IIIA lineage.

    Science.gov (United States)

    Roszniowski, Bartosz; Latka, Agnieszka; Maciejewska, Barbara; Vandenheuvel, Dieter; Olszak, Tomasz; Briers, Yves; Holt, Giles S; Valvano, Miguel A; Lavigne, Rob; Smith, Darren L; Drulis-Kawa, Zuzanna

    2017-02-01

    Burkholderia phage AP3 (vB_BceM_AP3) is a temperate virus of the Myoviridae and the Peduovirinae subfamily (P2likevirus genus). This phage specifically infects multidrug-resistant clinical Burkholderia cenocepacia lineage IIIA strains commonly isolated from cystic fibrosis patients. AP3 exhibits high pairwise nucleotide identity (61.7 %) to Burkholderia phage KS5, specific to the same B. cenocepacia host, and has 46.7-49.5 % identity to phages infecting other species of Burkholderia. The lysis cassette of these related phages has a similar organization (putative antiholin, putative holin, endolysin, and spanins) and shows 29-98 % homology between specific lysis genes, in contrast to Enterobacteria phage P2, the hallmark phage of this genus. The AP3 and KS5 lysis genes have conserved locations and high amino acid sequence similarity. The AP3 bacteriophage particles remain infective up to 5 h at pH 4-10 and are stable at 60 °C for 30 min, but are sensitive to chloroform, with no remaining infective particles after 24 h of treatment. AP3 lysogeny can occur by stable genomic integration and by pseudo-lysogeny. The lysogenic bacterial mutants did not exhibit any significant changes in virulence compared to wild-type host strain when tested in the Galleria mellonella moth wax model. Moreover, AP3 treatment of larvae infected with B. cenocepacia revealed a significant increase (P < 0.0001) in larvae survival in comparison to AP3-untreated infected larvae. AP3 showed robust lytic activity, as evidenced by its broad host range, the absence of increased virulence in lysogenic isolates, the lack of bacterial gene disruption conditioned by bacterial tRNA downstream integration site, and the absence of detected toxin sequences. These data suggest that the AP3 phage is a promising potent agent against bacteria belonging to the most common B. cenocepacia IIIA lineage strains.

  8. Connexin30-deficient mice show increased emotionality and decreased rearing activity in the open-field along with neurochemical changes.

    Science.gov (United States)

    Dere, E; De Souza-Silva, M A; Frisch, C; Teubner, B; Söhl, G; Willecke, K; Huston, J P

    2003-08-01

    Gap-junction channels in the brain, formed by connexin (Cx) proteins with a distinct regional/cell-type distribution, allow intercellular electrical and metabolic communication. In astrocytes, mainly the connexins 43, 26 and 30 are expressed. In addition, connexin30 is expressed in ependymal and leptomeningeal cells, as well as in skin and cochlea. The functional implications of the astrocytic gap-junctional network are not well understood and evidence regarding their behavioural relevance is lacking. Thus, we have tested groups of Cx30-/-, Cx30+/-, and Cx30+/+ mice in the open-field, an object exploration task, in the graded anxiety test and on the rotarod. The Cx30-/- mice showed reduced exploratory activity in terms of rearings but not locomotion in the open-field and object exploration task. Furthermore, Cx30-/- mice exhibited anxiogenic behaviour as shown by higher open-field centre avoidance and corner preference. Graded anxiety test and rotarod performance was similar across groups. The Cx30-/- mice had elevated choline levels in the ventral striatum, possibly related to their aberrant behavioural phenotypes. The Cx30+/- mice had lower dopamine and metabolite levels in the amygdala and ventral striatum and lower hippocampal 5-hydroxyindole acid (5-HIAA) concentrations relative to Cx30+/+ mice. Furthermore, the Cx30+/- mice had lower acetylcholine concentrations in the ventral striatum and higher choline levels in the neostriatum, relative to Cx30+/+ mice. Our data suggest that the elimination of connexin30 can alter the reactivity to novel environments, pointing to the importance of gap-junctional signalling in behavioural processes.

  9. Production of Active Nonglycosylated Recombinant B-Chain of Type-2 Ribosome-Inactivating Protein from Viscum articulatum and Its Biological Effects on Peripheral Blood Mononuclear Cells

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    Tzu-Li Lu

    2011-01-01

    Full Text Available Type-2 ribosome-inactivating proteins, composed of a toxic A-chain and lectin-like B-chain, display various biological functions, including cytotoxicity and immunomodulation. We here cloned the lectin-like B-chain encoding fragment of a newly identified type-2 RIP gene, articulatin gene, from Viscum articulatum, into a bacterial expression vector to obtain nonglycosylated recombinant protein expressed in inclusion bodies. After purification and protein refolding, soluble refolded recombinant articulatin B-chain (rATB showed lectin activity specific toward galactoside moiety and was stably maintained while stored in low ionic strength solution. Despite lacking glycosylation, rATB actively bound leukocytes with preferential binding to monocytes and in vitro stimulated PBMCs to release cytokines without obvious cytotoxicity. These results implicated such a B-chain fragment as a potential immunomodulator.

  10. New Activity of a Protein from Canavalia ensiformis

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    Vanya Petkova BOGOEVA

    2014-06-01

    Full Text Available Concanavalin A is a legume lectin which preferentially agglutinates transformed cells and shows antitumor effects on human breast carcinoma cells in vitro and in vivo. It is considered as a new potential antineoplastic agent targeting apoptosis, autophagy, and anti-angiogenesis in preclinical or clinical trials for cancer therapeutics, which has recently become the object of intensive study. In the present investigation, we show the capacity of the lectin to bind manganese, gold, iron, and zinc porphyrins: all potential anticancer agents. The interaction of the legume lectin with the studied compounds has been investigated by tryptophan fluorescence, showing conformational changes within the quaternary and tertiary structures of the protein. The binding of Con A with manganese, gold, and iron porphyrins, as well as adenine, was studied by fluorescence quenching. In contrast, the interaction of Con A with zinc porphyrin caused an increase in Trp fluorescence and a red shift of 10 nm of the emission maximum position. However, the binding of Con A to iron porphyrin was accompanied by a 5 nm blue shift of the emission maximum, and a kD of 0.95 ± 0.13 μM was calculated, respectively. The sigmoidal shape of the curve showed cooperative interactions, which indicated the presence of more than one class of binding site within the Con A molecule for iron porphyrin, confirmed by the Hill slope (h = 1.89±0.46. We have found that the legume lectin interacts with porphyrins and adenine with an affinity (0.14–1.89 μM similar to that of the non-legume lectin, wheat germ agglutinin. In conclusion, the protein Con A shows new binding activity towards porphyrins with anticancer activities and could find prospective application as a drug delivery molecule that specifically targets cancer cells.

  11. Ferromagnetic Levan Composite: An Affinity Matrix to Purify Lectin

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    Renata Angeli

    2009-01-01

    Full Text Available A simple and inexpensive procedure used magnetite and levan to synthesize a composite recovered by a magnetic field. Lectins from Canavalia ensiformis (Con A and Cratylia mollis (Cramoll 1 and Cramoll 1,4 did bind specifically to composite. The magnetic property of derivative favored washing out contaminating proteins and recovery of pure lectins with glucose elution. Cramoll 1 was purified by this affinity binding procedure in two steps instead of a previous three-step protocol with ammonium sulfate fractionation, affinity chromatography on Sephadex G-75, and ion exchange chromatography through a CM-cellulose column.

  12. Lung Adenocarcinomas and Lung Cancer Cell Lines Show Association of MMP-1 Expression With STAT3 Activation

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    Alexander Schütz

    2015-04-01

    Full Text Available Signal transducer and activator of transcription 3 (STAT3 is constitutively activated in the majority of lung cancer. This study aims at defining connections between STAT3 function and the malignant properties of non–small cell lung carcinoma (NSCLC cells. To address possible mechanisms by which STAT3 influences invasiveness, the expression of matrix metalloproteinase-1 (MMP-1 was analyzed and correlated with the STAT3 activity status. Studies on both surgical biopsies and on lung cancer cell lines revealed a coincidence of STAT3 activation and strong expression of MMP-1. MMP-1 and tyrosine-phosphorylated activated STAT3 were found co-localized in cancer tissues, most pronounced in tumor fronts, and in particular in adenocarcinomas. STAT3 activity was constitutive, although to different degrees, in the lung cancer cell lines investigated. Three cell lines (BEN, KNS62, and A549 were identified in which STAT3 activitation was inducible by Interleukin-6 (IL-6. In A549 cells, STAT3 activity enhanced the level of MMP-1 mRNA and stimulated transcription from the MMP-1 promoter in IL-6–stimulated A549 cells. STAT3 specificity of this effect was confirmed by STAT3 knockdown through RNA interference. Our results link aberrant activity of STAT3 in lung cancer cells to malignant tumor progression through up-regulation of expression of invasiveness-associated MMPs.

  13. Imidazopyridine-Based Fatty Acid Synthase Inhibitors That Show Anti-HCV Activity and in Vivo Target Modulation.

    Science.gov (United States)

    Oslob, Johan D; Johnson, Russell J; Cai, Haiying; Feng, Shirley Q; Hu, Lily; Kosaka, Yuko; Lai, Julie; Sivaraja, Mohanram; Tep, Samnang; Yang, Hanbiao; Zaharia, Cristiana A; Evanchik, Marc J; McDowell, Robert S

    2013-01-10

    Potent imidazopyridine-based inhibitors of fatty acid synthase (FASN) are described. The compounds are shown to have antiviral (HCV replicon) activities that track with their biochemical activities. The most potent analogue (compound 19) also inhibits rat FASN and inhibits de novo palmitate synthesis in vitro (cell-based) as well as in vivo.

  14. Evidence from northwest European bogs shows ‘Little Ice Age’ climatic changes driven by variations in solar activity

    NARCIS (Netherlands)

    Mauquoy, D; van Geel, B; Blaauw, Maarten; van der Plicht, J

    2002-01-01

    Fluctuations in Holocene atmospheric radiocarbon concentrations have been shown to be due to variations in solar activity. Analyses of both Be-10 and C-14 nuclides confirm that production-rate changes during the Holocene were largely modulated by solar activity. Analyses of peat samples from two

  15. Potential effects of Cramoll 1,4 lectin on murine Schistosomiasis mansoni.

    Science.gov (United States)

    Melo, Cristiane Moutinho Lagos de; de Lima, Amanda Lucena Rosendo; Beltrão, Eduardo Isidoro Carneiro; Cavalcanti, Carmelita C Bezerra; de Melo-Júnior, Mário Ribeiro; Montenegro, Silvia Maria L; Coelho, Luana Cassandra B Barroso; Correia, Maria Tereza dos Santos; Carneiro-Leão, Ana Maria dos Anjos

    2011-05-01

    Cratylia mollis is a natural forage plant from the Northeast of Brazil. C. mollis seed lectin (Cramoll) containing molecular forms 1 and 4 (Cramoll 1,4) has shown anti-inflammatory and wound-healing activities. This work analyzed the effect of Cramoll 1,4 on experimental schistosomiasis in mice. Experimental groups (n=15/group) were composed of female albino Swiss mice, which were subcutaneously and caudally infected with Schistosoma mansoni (BH strain, 100 cercariae/mouse) and were treated with an intraperitoneal dose after infection as follows: (1) Cramoll 1,4 (50 mg kg(-1) single dose - after 40 days of infection), (2) Cramoll 1,4 (7 mg kg(-1) daily dose - for 7 days after infection) and control (untreated mice). Mice were sacrificed 8 weeks after infection and adult worms were recovered from the portal-hepatic system. Livers were fixed in 10% (v/v) formaldehyde/0.15M NaCl and tissue sections were processed for haematoxilin and Masson's trichrome stainings. Mice infected subcutaneously harboured no or very few worms and hence the effect of Cramoll 1,4 could not be assessed. Results (P≤0.05) were obtained with Cramoll 1,4 using the two treatments, with reduction of: egg excretion (79 and 80%), adult worm recovery (71 and 79%) and liver granulomas (40 and 73.5%) in relation to control. This study showed the potential anti-helminthic activity of Cramoll 1,4 when tested against Schistosomiasis mansoni infection in mice. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Thermal, chemical and pH induced unfolding of turmeric root lectin: modes of denaturation.

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    Himadri Biswas

    Full Text Available Curcuma longa rhizome lectin, of non-seed origin having antifungal, antibacterial and α-glucosidase inhibitory activities, forms a homodimer with high thermal stability as well as acid tolerance. Size exclusion chromatography and dynamic light scattering show it to be a dimer at pH 7, but it converts to a monomer near pH 2. Circular dichroism spectra and fluorescence emission maxima are virtually indistinguishable from pH 7 to 2, indicating secondary and tertiary structures remain the same in dimer and monomer within experimental error. The tryptophan environment as probed by acrylamide quenching data yielded very similar data at pH 2 and pH 7, implying very similar folding for monomer and dimer. Differential scanning calorimetry shows a transition at 350.3 K for dimer and at 327.0 K for monomer. Thermal unfolding and chemical unfolding induced by guanidinium chloride for dimer are both reversible and can be described by two-state models. The temperatures and the denaturant concentrations at which one-half of the protein molecules are unfolded, are protein concentration-dependent for dimer but protein concentration-independent for monomer. The free energy of unfolding at 298 K was found to be 5.23 Kcal mol-1 and 14.90 Kcal mol-1 for the monomer and dimer respectively. The value of change in excess heat capacity upon protein denaturation (ΔCp is 3.42 Kcal mol-1 K-1 for dimer. The small ΔCp for unfolding of CLA reflects a buried hydrophobic core in the folded dimeric protein. These unfolding experiments, temperature dependent circular dichroism and dynamic light scattering for the dimer at pH 7 indicate its higher stability than for the monomer at pH 2. This difference in stability of dimeric and monomeric forms highlights the contribution of inter-subunit interactions in the former.

  17. Effect of the lectins wheat germ agglutinin (WGA) and Ulex europaeus agglutinin (UEA-I) on the alpha-amylase secretion of rat pancreas in vitro and in vivo.

    Science.gov (United States)

    Mikkat, U; Damm, I; Schröder, G; Schmidt, K; Wirth, C; Weber, H; Jonas, L

    1998-05-01

    Lectins are able to bind to cholecystokinin (CCK) receptors and other glycosylated membrane proteins. The lectins wheat germ agglutinin (WGA) and Ulex europaeus agglutinin (UEA-I) are used for affinity chromatography to isolate the highly glycosylated CCK-A receptor of pancreatic acinar cells. According to the working hypothesis that lectin binding to the CCK receptor should alter the ligand-receptor interaction, the effect of WGA and UEA-I on CCK-8-induced enzyme secretion was studied on isolated rat pancreatic acini in vitro. In vitro both lectins showed a dosage-dependent inhibition of CCK-8-induced alpha-amylase secretion of acini over 60 min. WGA showed a strong inhibitory effect on amylase secretion, approximately 40%, in vitro. UEA-I caused a smaller, but significant decrease, approximately 20%, in enzyme secretion of isolated acini. Additionally, both lectins inhibited cerulein/secretin- or cerulein-induced pancreatic secretion of rats in vivo, but not after secretin alone. The results are discussed with respect to a possible influence of both lectins on the interaction of CCK or cerulein with the CCK-A receptor.

  18. The Arabidopsis thaliana lectin receptor kinase LecRK-I.9 is required for full resistance to Pseudomonas syringae and affects jasmonate signalling.

    Science.gov (United States)

    Balagué, Claudine; Gouget, Anne; Bouchez, Olivier; Souriac, Camille; Haget, Nathalie; Boutet-Mercey, Stéphanie; Govers, Francine; Roby, Dominique; Canut, Hervé

    2017-09-01

    On microbial attack, plants can detect invaders and activate plant innate immunity. For the detection of pathogen molecules or cell wall damage, plants employ receptors that trigger the activation of defence responses. Cell surface proteins that belong to large families of lectin receptor kinases are candidates to function as immune receptors. Here, the function of LecRK-I.9 (At5g60300), a legume-type lectin receptor kinase involved in cell wall-plasma membrane contacts and in extracellular ATP (eATP) perception, was studied through biochemical, gene expression and reverse genetics approaches. In Arabidopsis thaliana, LecRK-I.9 expression is rapidly, highly and locally induced on inoculation with avirulent strains of Pseudomonas syringae pv. tomato (Pst). Two allelic lecrk-I.9 knock-out mutants showed decreased resistance to Pst. Conversely, over-expression of LecRK-I.9 led to increased resistance to Pst. The analysis of defence gene expression suggests an alteration of both the salicylic acid (SA) and jasmonic acid (JA) signalling pathways. In particular, LecRK-I.9 expression during plant-pathogen interaction was dependent on COI1 (CORONATINE INSENSITIVE 1) and JAR1 (JASMONATE RESISTANT 1) components, and JA-responsive transcription factors (TFs) showed altered levels of expression in plants over-expressing LecRK-I.9. A similar misregulation of these TFs was obtained by JA treatment. This study identified LecRK-I.9 as necessary for full resistance to Pst and demonstrated its involvement in the control of defence against pathogens through a regulation of JA signalling components. The role of LecRK-I.9 is discussed with regard to the potential molecular mechanisms linking JA signalling to cell wall damage and/or eATP perception. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  19. Monomeric banana lectin at acidic pH overrules conformational stability of its native dimeric form.

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    Javed M Khan

    Full Text Available Banana lectin (BL is a homodimeric protein categorized among jacalin-related family of lectins. The effect of acidic pH was examined on conformational stability of BL by using circular dichroism, intrinsic fluorescence, 1-anilino-8-napthalene sulfonate (ANS binding, size exclusion chromatography (SEC and dynamic light scattering (DLS. During acid denaturation of BL, the monomerization of native dimeric protein was found at pH 2.0. The elution profile from SEC showed two different peaks (59.65 ml & 87.98 ml at pH 2.0 while single peak (61.45 ml at pH 7.4. The hydrodynamic radii (R h of native BL was 2.9 nm while at pH 2.0 two species were found with R h of 1.7 and 3.7 nm. Furthermore at, pH 2.0 the secondary structures of BL remained unaltered while tertiary structure was significantly disrupted with the exposure of hydrophobic clusters confirming the existence of molten globule like state. The unfolding of BL with different subunit status was further evaluated by urea and temperature mediated denaturation to check their stability. As inferred from high Cm and ΔG values, the monomeric form of BL offers more resistance towards chemical denaturation than the native dimeric form. Besides, dimeric BL exhibited a Tm of 77°C while no loss in secondary structures was observed in monomers even up to 95°C. To the best of our knowledge, this is the first report on monomeric subunit of lectins showing more stability against denaturants than its native dimeric state.

  20. The galactose-binding lectin isolated from Bauhinia bauhinioides Mart seeds inhibits neutrophil rolling and adhesion via primary cytokines.

    Science.gov (United States)

    Girão, Deysen Kerlla Fernandes Bezerra; Cavada, Benildo Sousa; de Freitas Pires, Alana; Martins, Timna Varela; Franco, Álvaro Xavier; Morais, Cecília Mendes; Santiago do Nascimento, Kyria; Delatorre, Plinio; da Silva, Helton Colares; Nagano, Celso Shiniti; Assreuy, Ana Maria Sampaio; Soares, Pedro Marcos Gomes

    2015-05-01

    In this study, the amino acid sequence and anti-inflammatory effect of Bauhinia bauhinioides (BBL) lectin were evaluated. Tandem mass spectrometry revealed that BBL possesses 86 amino acid residues. BBL (1 mg/kg) intravenously injected in rats 30 min prior to inflammatory stimuli inhibited the cellular edema induced by carrageenan in only the second phase (21% - 3 h, 19% - 4 h) and did not alter the osmotic edema induced by dextran. BBL also inhibited