Sample records for lectins

  1. Lectins with anti-HIV activity: a review.

    PubMed

    Akkouh, Ouafae; Ng, Tzi Bun; Singh, Senjam Sunil; Yin, Cuiming; Dan, Xiuli; Chan, Yau Sang; Pan, Wenliang; Cheung, Randy Chi Fai

    2015-01-06

    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. Two C-type lectins from shrimp Litopenaeus vannamei that might be involved in immune response against bacteria and virus.

    PubMed

    Wei, Xiumei; Liu, Xiangquan; Yang, Jianmin; Fang, Jinghui; Qiao, Hongjin; Zhang, Ying; Yang, Jialong

    2012-01-01

    C-type lectins play crucial roles in innate immunity to recognize and eliminate pathogens efficiently. In the present study, two C-type lectins from shrimp Litopenaeus vannamei (designated as LvLectin-1 and LvLectin-2) were identified, and their expression patterns, both in tissues and toward pathogen stimulation, were then characterized. The full-length cDNA of LvLectin-1 and LvLectin-2 was 567 and 625 bp, containing an open reading frame (ORF) of 471 and 489 bp, respectively, and deduced amino acid sequences showed high similarity to other members of C-type lectin superfamily. Both two C-type lectins encoded a single carbohydrate-recognition domain (CRD). The motif of Ca(2+) binding site 2 in CRD, which determined carbohydrate-binding specificity, was QPN (Gln(122)-Pro(123)-Asn(124)) in LvLectin-1, but QPD (Gln(128)-Pro(129)-Asp(130)) in LvLectin-2. Two C-type lectins exhibited similar tissue expression pattern, for their mRNA were both constitutively expressed in all tested tissues, including hepatopancreas, muscle, gill, hemocytes, gonad and heart, furthermore they were both mostly expressed in hepatopancreas, though the expression level of LvLectin-2 was much higher than LvLectin-1. The expression level of two C-type lectins mRNA in hemocytes varied greatly after the challenge of Listonella anguillarum or WSSV. After L. anguillarum challenge, the expression of both C-type lectins were significantly (P<0.01) up-regulated compared with blank group, and LvLectin-1 exhibited higher level than LvLectin-2; while after the stimulation of WSSV, the expression of LvLectin-2 was significantly up-regulated at 6 h (P<0.01) and 12 h (P<0.05), but the expression level of LvLectin-1 down-regulated significantly (P<0.01) to 0.4-fold at 6 and 12 h post-stimulation. The results indicated that the two C-type lectins might be involved in immune response toward pathogen infection, and they might perform different recognition specificity toward bacteria or virus. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

    PubMed

    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.

  4. Lectins: production and practical applications

    PubMed Central

    2010-01-01

    Lectins are proteins found in a diversity of organisms. They possess the ability to agglutinate erythrocytes with known carbohydrate specificity since they have at least one non-catalytic domain that binds reversibly to specific monosaccharides or oligosaccharides. This articles aims to review the production and practical applications of lectins. Lectins are isolated from their natural sources by chromatographic procedures or produced by recombinant DNA technology. The yields of animal lectins are usually low compared with the yields of plant lectins such as legume lectins. Lectins manifest a diversity of activities including antitumor, immunomodulatory, antifungal, HIV-1 reverse transcriptase inhibitory, and anti-insect activities, which may find practical applications. A small number of lectins demonstrate antibacterial and anti-nematode activities. PMID:20890754

  5. Comparative study of hemagglutination and lectin activity in Australian medicinal mushrooms (higher Basidiomycetes).

    PubMed

    Rouf, Razina; Tiralongo, Evelin; Krahl, Anja; Maes, Karen; Spaan, Lina; Wolf, Stefan; May, Tom W; Tiralongo, Joe

    2011-01-01

    Fifteen Australian mushroom species (higher Basidiomycetes) were assessed for hemagglutination and lectin activity. Hemagglutination activity was evaluated using both neuraminidase treated and untreated rabbit and human A, B, and O erythrocytes. Lectin activity was determined by the ability of various mono- and oligosaccharides to inhibit hemagglutination activity. Of the mushrooms evaluated, seven contained lectin activity. However, five (Agaricus bitorquis, Chlorophyllum brunneum, Coprinus comatus, Cortinarius sp. TWM 1710, and Omphalotus nidiformis) expressed lectin activity in only one of two collections tested. The two remaining lectin active mushroom species (Phlebopus marginatus and Psathyrella asperospora) possessed lectin activity with the same sugar specificity in both collections. Although lectins were identified with diverse specificity, lactose-specific lectin activity was most frequently identified, being present in Agaricus bitorquis, Copronus comatus, Omphalotus nidiformis, and Phlebopus marginatus. In contrast, Psathyrella asperospora, Cortinarius sp. TWM 1710, and Chlorophyllum brunneum were found to possess lectin activity specific for N-acetyl-D-glucosamine, galactose, and N-acetyl-neurammic acid, respectively. Significantly, the galactose-specific lectin activity identified in Cortinarius sp. TWM 1710 and the lactose-specific lectin activity in Phlebopus marginatus have not been previously reported.

  6. Lectins of beneficial microbes: system organisation, functioning and functional superfamily.

    PubMed

    Lakhtin, M; Lakhtin, V; Alyoshkin, V; Afanasyev, S

    2011-06-01

    In this review our last results and proposals with respect to general aspects of lectin studies are summarised and compared. System presence, organisation and functioning of lectins are proposed, and accents on beneficial symbiotic microbial lectins studies are presented. The proposed general principles of lectin functioning allows for a comparison of lectins with other carbohydrate-recognition systems. A new structure-functional superfamily of symbiotic microbial lectins is proposed and its main properties are described. The proposed superfamily allows for extended searches of the biological activities of any microbial member. Prospects of lectins of beneficial symbiotic microorganisms are discussed.

  7. Interactions of lectins with plasma membrane glycoproteins of the Ehrlich ascites carcinoma cell.

    PubMed

    Nachbar, M S; Oppenheim, J D; Aull, F

    1976-02-06

    Several aspects of the interaction of various lectins with the surface of Ehrlich ascites carcinoma cells are described. The order of agglutinating activity for various lectins is Ricinus communis greater than wheat germ greater than or equal to concanavalin A greater than or equal to soybean greater than Limulus polyphemus. No agglutination was noted for Ulex europaeus. Using 125I-labeled lectins it was determined that there are 1.6 and 7 times as many Ricinus communis lectin binding sites for concanavalin A and soybean lectins. Sodium deoxycholate-solubilized plasma membrane material was subjected to lectin affinity chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The lectin receptors of the plasma membrane appeared to be heterogeneous and some qualitative differences could be discerned among the electrophoretically analyzed material, which bound to and was specifically eluted from the various lectin affinity columns. The characteristics of elution of bound material from individual lectin columns indicated secondary hydrophobic interactions between concanavalin A or wheat germ agglutinin and their respective lectin receptor molecules.

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

    PubMed

    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.

  9. Purification and Characterization of a Mucin Specific Mycelial Lectin from Aspergillus gorakhpurensis: Application for Mitogenic and Antimicrobial Activity

    PubMed Central

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

    2014-01-01

    Background 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. Methods 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. Results 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. Conclusion This is the first report on the mitogenic and antimicrobial potential of Aspergillus gorakhpurensis lectin. The results will provide useful guidelines for further research in clinical applications of this lectin. PMID:25286160

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

    PubMed

    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 results will provide useful guidelines for further research in clinical applications of this lectin.

  11. A Human Lectin Microarray for Sperm Surface Glycosylation Analysis *

    PubMed Central

    Sun, Yangyang; Cheng, Li; Gu, Yihua; Xin, Aijie; Wu, Bin; Zhou, Shumin; Guo, Shujuan; Liu, Yin; Diao, Hua; Shi, Huijuan; Wang, Guangyu; Tao, Sheng-ce

    2016-01-01

    Glycosylation is one of the most abundant and functionally important protein post-translational modifications. As such, technology for efficient glycosylation analysis is in high demand. Lectin microarrays are a powerful tool for such investigations and have been successfully applied for a variety of glycobiological studies. However, most of the current lectin microarrays are primarily constructed from plant lectins, which are not well suited for studies of human glycosylation because of the extreme complexity of human glycans. Herein, we constructed a human lectin microarray with 60 human lectin and lectin-like proteins. All of the lectins and lectin-like proteins were purified from yeast, and most showed binding to human glycans. To demonstrate the applicability of the human lectin microarray, human sperm were probed on the microarray and strong bindings were observed for several lectins, including galectin-1, 7, 8, GalNAc-T6, and ERGIC-53 (LMAN1). These bindings were validated by flow cytometry and fluorescence immunostaining. Further, mass spectrometry analysis showed that galectin-1 binds several membrane-associated proteins including heat shock protein 90. Finally, functional assays showed that binding of galectin-8 could significantly enhance the acrosome reaction within human sperms. To our knowledge, this is the first construction of a human lectin microarray, and we anticipate it will find wide use for a range of human or mammalian studies, alone or in combination with plant lectin microarrays. PMID:27364157

  12. Laccase and lectin activities of intracellular proteins produced in a submerged culture of the xylotrophic basidiomycete Lentinus edodes.

    PubMed

    Vetchinkina, Elena P; Pozdnyakova, Natalia N; Nikitina, Valentina E

    2008-10-01

    The white-rot fungus Lentinus edodes produced D-melibiose-specific lectins and two laccase forms in a lignin-containing medium. The maxima of laccase and lectin activities coincided, falling within the period of active mycelial growth. The enzymes and lectins were isolated and purified by gel filtration followed by anion-exchange chromatography. The L. edodes lectins were found to be able to stabilize the activity of the fungus's own laccases. Lectin activity during the formation of lectin-enzyme complexes remained unchanged.

  13. Effect of gamma irradiation on mistletoe (Viscum album) lectin-mediated toxicity and immunomodulatory activity☆

    PubMed Central

    Sung, Nak-Yun; Byun, Eui-Baek; Song, Du-Sup; Jin, Yeung-Bae; Kim, Jae-Kyung; Park, Jong-Heum; Song, Beom-Seok; Jung, Pil-Mun; Byun, Myung-Woo; Lee, Ju-Woon; Park, Sang-Hyun; Kim, Jae-Hun

    2013-01-01

    This study evaluated the effect of gamma irradiation on the reduction of the toxicity of mistletoe lectin using both in vitro and in vivo models. To extract the lectin from mistletoe, an (NH4)2SO4 precipitation method was employed and the precipitant purified using a Sepharose 4B column to obtain the pure lectin fraction. Purified lectin was then gamma-irradiated at doses of 0, 5, 10, 15, and 20 kGy, or heated at 100 °C for 30 min. Toxic effects of non-irradiated, irradiated, and heat-treated lectins were tested using hemagglutination assays, cytotoxicity assays, hepatotoxicity, and a mouse survival test and immunological response was tested using cytokine production activity. Hemagglutination of lectin was remarkably decreased (P < 0.05) by irradiation at doses exceeding 10 kGy and with heat treatment. However, lectin irradiated with 5 kGy maintained its hemagglutination activity. The cytotoxicity of lectin was decreased by irradiation at doses over 5 kGy and with heat treatment. In experiments using mouse model, glutamate oxaloacetate transaminase (GOT) and glutamic pyruvic transaminase (GPT) levels were decreased in the group treated with the 5 kGy irradiated and heat-treated lectins as compared to the intact lectin, and it was also shown that 5 kGy irradiated and heat-treated lectins did not cause damage in liver tissue or mortality. In the result of immunological response, tumor necrosis factor (TNF-α) and interleukin (IL-6) levels were significantly (P < 0.05) increased in the 5 kGy gamma-irradiated lectin treated group. These results indicate that 5 kGy irradiated lectin still maintained the immunological response with reduction of toxicity. Therefore, gamma-irradiation may be an effective method for reducing the toxicity of lectin maintaining the immune response. PMID:23847758

  14. Lectin engineering, a molecular evolutionary approach to expanding the lectin utilities.

    PubMed

    Hu, Dan; Tateno, Hiroaki; Hirabayashi, Jun

    2015-04-27

    In the post genomic era, glycomics--the systematic study of all glycan structures of a given cell or organism--has emerged as an indispensable technology in various fields of biology and medicine. Lectins are regarded as "decipherers of glycans", being useful reagents for their structural analysis, and have been widely used in glycomic studies. However, the inconsistent activity and availability associated with the plant-derived lectins that comprise most of the commercially available lectins, and the limit in the range of glycan structures covered, have necessitated the development of innovative tools via engineering of lectins on existing scaffolds. This review will summarize the current state of the art of lectin engineering and highlight recent technological advances in this field. The key issues associated with the strategy of lectin engineering including selection of template lectin, construction of a mutagenesis library, and high-throughput screening methods are discussed.

  15. Histological and Lectin Histochemical Studies on the Olfactory and Respiratory Mucosae of the Sheep

    PubMed Central

    IBRAHIM, Dalia; NAKAMUTA, Nobuaki; TANIGUCHI, Kazumi; YAMAMOTO, Yoshio; TANIGUCHI, Kazuyuki

    2013-01-01

    ABSTRACT The olfactory and respiratory mucosae of the Corriedale sheep were examined using lectin histochemistry in order to clarify the histochemical and glycohistochemical differences between these two tissues. The olfactory epithelium was stained with 13 lectins out of 21 lectins examined, while the respiratory epithelium was positive to 16 lectins. The free border of both of the olfactory and respiratory epithelia was stained with 12 lectins: Wheat germ agglutinin (WGA), succinylated-wheat germ agglutinin (s-WGA), Lycopersicon esculentum lectin (LEL), Solanum tuberosum lectin (STL), Datura stramonium lectin (DSL), Soybean agglutinin (SBA), Bandeiraea simplicifolia lectin-I (BSL-I), Ricinus communis agglutinin-I (RCA-120), Erythrina cristagalli lectin (ECL), Concanavalin A (Con A), Phaseolus vulgaris agglutinin-E (PHA-E) and Phaseolus vulgaris agglutinin-L (PHA-L). The associated glands of the olfactory mucosa, Bowman’s glands, were stained with 13 lectins. While both the goblet cells and mucous nasal glands were stained with 8 lectins; five of them (WGA, s-WGA, STL, Vicia villosa agglutinin (VVA) and ECL) were mutually positive among the Bowman’s glands, mucous nasal glands and the goblet cells. These findings indicate that the glycohistochemical characteristics of the free borders of both olfactory and respiratory epithelia are similar to each other, suggesting that secretions from the Bowman’s glands and those of the goblet cells and mucous nasal glands are partially exchanged between the surface of two epithelia to contribute the functions of the respiratory epithelium and the olfactory receptor cells, respectively. PMID:24200894

  16. Histochemical analysis of glycoconjugates in the skin of a catfish (arius tenuispinis, day).

    PubMed

    Al-Banaw, A; Kenngott, R; Al-Hassan, J M; Mehana, N; Sinowatz, F

    2010-02-01

    A histochemical study using conventional carbohydrate histochemistry (periodic-acid staining including diastase controls, alcian blue staining at pH 1 and 2.5) as well as using a battery of 14 fluorescein isothiocyanate (FITC)-labelled lectins to identify glycoconjugates present in 10 different areas of the skin of a catfish (Arius tenuispinis) was carried out. The lectins used were: mannose-binding lectins (Con A, LCA and PSA), galactose-binding lectins (PNA, RCA), N-acetylgalactosamine-binding lectins (DBA, SBA, SJA and GSL I), N-acetylglucosamine-binding lectins (WGA and WGAs), fucose-binding lectins (UEA) and lectins which bind to complex carbohydrate configurations (PHA E, PHA L). Conventional glycoconjugate staining (PAS staining, alcian blue at pH 1 and 2.5) showed that the mucous goblet cells contain a considerable amount of glycoconjugates in all locations of the skin, whereas the other unicellular gland type, the club cells, lacked these glycoconjugates. The glycoproteins found in goblet cells are neutral and therefore stain magenta when subjected to PAS staining. Alcian blue staining indicating acid glycoproteins was distinctly positive at pH 1, but gave only a comparable staining at pH 2.5. The mucus of the goblet cells therefore also contains acid glycoproteins rich in sulphate groups. Using FITC-labelled lectins, the carbohydrate composition of the glycoproteins of goblet cells could be more fully characterized. A distinct staining of the mucus of goblet cells was found with the mannose-binding lectins LCA and PSA; the galactosamine-binding lectins DBA, SBA and GLS I; the glucosamine-binding lectin WGA; and PHA E which stains glycoproteins with complex carbohydrate configurations. No reaction occurred with the fucose-binding lectin UEA and the sialic acid-specific lectin SNA. In addition, the galactose-binding lectins PNA and RCA showed only a weak or completely negative staining of the mucus in the goblet cells. The specificity of the lectin staining could be proved by inhibiting binding of the lectins by competitive inhibition with the corresponding sugars. From these data, we can conclude that the mucus produced by the epidermal goblet cells of A. tenuispinis is rich in mannose, N-acetylgalactosamine and N-acetylglucosamine residues.

  17. Lectins in fruits having gastrointestinal activity: their participation in the hemagglutinating property of Escherichia coli O157:H7.

    PubMed

    Coutiño-Rodríguez, R; Hernández-Cruz, P; Giles-Ríos, H

    2001-01-01

    In fruits with therapeutic properties for antidiarrheal and laxative uses, the presence of lectins may be the bioactive properties that interfere with bacterial adhesion, thought to be competition for glycoside signal sites in the attachment. This study identifies lectins in crude extracts from fruits such as Tamarindus indica (tamarind), Spontia vulgaris (plum), Psidium guava (guava), Mangifera indica (mango), Cydonia vulgaris (quince), and Crataegus mexicanus (tejocote). To verify the procedures, extracts from Ricinus communis (castor bean), Glycine max (soybean), Phaseolus vulgaris (beans), Vicia fava (fava bean), and Solanum tuberosum (potato) were used as controls for lectin activity. Both sources of lectins were analyzed to determine their participation in the host-parasite interaction, using as a model the hemagglutinating properties of Escherichia coli O157:H7 (EHA). All extracts showed hemagglutination to group O erythrocytes test (HA) with the exception of mango. Two new galactose-specific lectins were identified from tamarind and guava. When analyzed for participation in EHA, only guava lectins inhibited this, while soybean lectin induced hemolysis; as both lectins bind to galactose, it is probable that their recognition occurs in different domains. Sugars involved in the attachment between Escherichia coli O157:H7 and red cells were identified and again, galactose in addition to mannose was found to be related in EHA. On the other hand, guava lectins also agglutinated E. coli O157:H7, perhaps due to the same galactose-specific lectin or to another type of lectin. In summary, guava has a galactose-specific lectin that prevents adhesion of E. coli O157:H7 to red cells; this lectin is mediated by galactose. Prevention could also be due to their capacity of agglutinating E. coli by guava lectins. Soybean lectin induced hemolysis only when bacteria was present, but not with floating secretions. This finding showed that guava is a source of lectin that can be explored to prevent adhesion of E. coli to epithelial intestinal cells; contrariwise, soya must be studied to see its participation in the uremia caused during E. coli O157:H7 pathogenesis.

  18. Purification and characterization of a novel thermostable mycelial lectin from Aspergillus terricola.

    PubMed

    Singh, Ram Sarup; Bhari, Ranjeeta; Kaur, Hemant Preet; Vig, Monika

    2010-11-01

    Lectin has been isolated from mycelia of Aspergillus terricola by single step purification on porcine stomach mucin-Sepharose 4B affinity column. Lectin could be effectively purified with 75% recovery and 4.47-fold increase in specific activity. Lectin migrated as a single band on SDS-PAGE with an apparent molecular mass of 32.5 kDa. Sugar inhibition assay revealed that the lectin did not strongly interact with most carbohydrates and their derivatives tested while strong binding affinity to D-glucose, D-sucrose, N-acetyl-D-galactosamine, asialofetuin, porcine stomach mucin, and bovine submaxillary mucin was indicated. Neuraminidase and protease treatment to erythrocytes enhanced lectin titre. Lectin activity was stable within the pH range of 7.0-10.5. A. terricola lectin displayed remarkable thermostability and remained unaffected upon incubation at 70 degrees C for 2.5 h. Lectin did not require metal ions for its activity. Incubation with denaturants (urea, thiourea, and guanidine-HCl) substantially reduced lectin activity. Carbohydrate analysis revealed that it is a glycoprotein with 9.76% total sugars.

  19. Lectins discriminate between pathogenic and nonpathogenic South American trypanosomes

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

    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 europaeusmore » 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.« less

  20. Sorafenib induced alteration of protein glycosylation in hepatocellular carcinoma cells

    PubMed Central

    Liu, Tianhua; Liu, Riqiang; Zhang, Shu; Guo, Kun; Zhang, Qinle; Li, Wei; Liu, Yinkun

    2017-01-01

    Sorafenib is a multikinase inhibitor and is effective in treating hepatocellular carcinoma (HCC). However, it remains unknown whether sorafenib induces the alteration of protein glycosylation. The present study treated HCC MHCC97L and MHCC97H cells with a 50% inhibitory concentration of sorafenib. Following this treatment, alteration of protein glycosylation was detected using a lectin microarray. Compared with the controls, the binding capacity of glycoproteins extracted from sorafenib-treated HCC cells to the lectins Bauhinia purpurea lectin, Dolichos biflorus agglutinin, Euonymus europaeus lectin, Helix aspersa lectin, Helix pomatia lectin, Jacalin, Maclura pomifera lectin and Vicia villosa lectin were enhanced; while, the binding capacities to the lectins Caragana arborescens lectin, Lycopersicon esculentum lectin, Limulus polyphemus lectin, Maackia amurensis lecin I, Phaseolus vulgaris leucoagglutinin, Ricinus communis agglutinin 60, Sambucus nigra lectin and Solanum tuberosum lectin were reduced (spot intensity median/background intensity median ≥2, P<0.05). This difference in glycoprotein binding capacity indicates that cells treated with sorafenib could increase α-1,3GalNAc/Gal, β-1,3 Gal, GalNAcα-Ser/Thr(Tn) and α-GalNAc structures and decrease GlcNAc, sialic acid, tetra-antennary complex-type N-glycan and β-1,4Gal structures. These results were additionally confirmed by lectin blotting. Expression levels of signaling molecules including erythroblastosis 26–1 (Ets-1), extracellular signal-related kinases (ERK) and phosphorylated-ERK were measured by western blotting. There was a reduction in the expression of Ets-1 and ERK phosphorylation in sorafenib or 1,4-Diamino-2,3-dicyano-1,4-bis (2-aminophenylthio) butadiene treated cells suggesting that sorafenib may reduce the expression levels of Ets-1 by blocking the Ras/Raf/mitogen activated protein kinase signaling pathway. In the present study, it was clear that sorafenib could inhibit the proliferation of HCC cells and alter protein glycosylation. The findings of this study may lead to providing a novel way of designing new anti-HCC drugs. PMID:28693200

  1. Use of lectin microarray to differentiate gastric cancer from gastric ulcer

    PubMed Central

    Huang, Wei-Li; Li, Yang-Guang; Lv, Yong-Chen; Guan, Xiao-Hui; Ji, Hui-Fan; Chi, Bao-Rong

    2014-01-01

    AIM: To investigate the feasibility of lectin microarray for differentiating gastric cancer from gastric ulcer. METHODS: Twenty cases of human gastric cancer tissue and 20 cases of human gastric ulcer tissue were collected and processed. Protein was extracted from the frozen tissues and stored. The lectins were dissolved in buffer, and the sugar-binding specificities of lectins and the layout of the lectin microarray were summarized. The median of the effective data points for each lectin was globally normalized to the sum of medians of all effective data points for each lectin in one block. Formalin-fixed paraffin-embedded gastric cancer tissues and their corresponding gastric ulcer tissues were subjected to Ag retrieval. Biotinylated lectin was used as the primary antibody and HRP-streptavidin as the secondary antibody. The glycopatterns of glycoprotein in gastric cancer and gastric ulcer specimens were determined by lectin microarray, and then validated by lectin histochemistry. Data are presented as mean ± SD for the indicated number of independent experiments. RESULTS: The glycosylation level of gastric cancer was significantly higher than that in ulcer. In gastric cancer, most of the lectin binders showed positive signals and the intensity of the signals was stronger, whereas the opposite was the case for ulcers. Significant differences in the pathological score of the two lectins were apparent between ulcer and gastric cancer tissues using the same lectin. For MPL and VVA, all types of gastric cancer detected showed stronger staining and a higher positive rate in comparison with ulcer, especially in the case of signet ring cell carcinoma and intra-mucosal carcinoma. GalNAc bound to MPL showed a significant increase. A statistically significant association between MPL and gastric cancer was observed. As with MPL, there were significant differences in VVA staining between gastric cancer and ulcer. CONCLUSION: Lectin microarray can differentiate the different glycopatterns in gastric cancer and gastric ulcer, and the lectins MPL and VVA can be used as biomarkers. PMID:24833877

  2. Visualizing the dental biofilm matrix by means of fluorescence lectin-binding analysis.

    PubMed

    Tawakoli, Pune N; Neu, Thomas R; Busck, Mette M; Kuhlicke, Ute; Schramm, Andreas; Attin, Thomas; Wiedemeier, Daniel B; Schlafer, Sebastian

    2017-01-01

    The extracellular matrix is a poorly studied, yet important component of dental biofilms. Fluorescence lectin-binding analysis (FLBA) is a powerful tool to characterize glycoconjugates in the biofilm matrix. This study aimed to systematically investigate the ability of 75 fluorescently labeled lectins to visualize and quantify extracellular glycoconjugates in dental biofilms. Lectin binding was screened on pooled supragingival biofilm samples collected from 76 subjects using confocal microscopy. FLBA was then performed with 10 selected lectins on biofilms grown in situ for 48 h in the absence of sucrose. For five lectins that proved particularly suitable, stained biovolumes were quantified and correlated to the bacterial composition of the biofilms. Additionally, combinations of up to three differently labeled lectins were tested. Of the 10 lectins, five bound particularly well in 48-h-biofilms: Aleuria aurantia (AAL), Calystega sepiem (Calsepa), Lycopersicon esculentum (LEA), Morniga-G (MNA-G) and Helix pomatia (HPA). No significant correlation between the binding of specific lectins and bacterial composition was found. Fluorescently labeled lectins enable the visualization of glycoconjugates in the dental biofilm matrix. The characterization and quantification of glycoconjugates in dental biofilms require a combination of several lectins. For 48-h-biofilms grown in absence of sucrose, AAL, Calsepa, HPA, LEA, and MNA-G are recommendable.

  3. Porifera Lectins: Diversity, Physiological Roles and Biotechnological Potential.

    PubMed

    Gardères, Johan; Bourguet-Kondracki, Marie-Lise; Hamer, Bojan; Batel, Renato; Schröder, Heinz C; Müller, Werner E G

    2015-08-07

    An overview on the diversity of 39 lectins from the phylum Porifera is presented, including 38 lectins, which were identified from the class of demosponges, and one lectin from the class of hexactinellida. Their purification from crude extracts was mainly performed by using affinity chromatography and gel filtration techniques. Other protocols were also developed in order to collect and study sponge lectins, including screening of sponge genomes and expression in heterologous bacterial systems. The characterization of the lectins was performed by Edman degradation or mass spectrometry. Regarding their physiological roles, sponge lectins showed to be involved in morphogenesis and cell interaction, biomineralization and spiculogenesis, as well as host defense mechanisms and potentially in the association between the sponge and its microorganisms. In addition, these lectins exhibited a broad range of bioactivities, including modulation of inflammatory response, antimicrobial and cytotoxic activities, as well as anticancer and neuromodulatory activity. In view of their potential pharmacological applications, sponge lectins constitute promising molecules of biotechnological interest.

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

    PubMed

    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.

  5. Porifera Lectins: Diversity, Physiological Roles and Biotechnological Potential

    PubMed Central

    Gardères, Johan; Bourguet-Kondracki, Marie-Lise; Hamer, Bojan; Batel, Renato; Schröder, Heinz C.; Müller, Werner E. G.

    2015-01-01

    An overview on the diversity of 39 lectins from the phylum Porifera is presented, including 38 lectins, which were identified from the class of demosponges, and one lectin from the class of hexactinellida. Their purification from crude extracts was mainly performed by using affinity chromatography and gel filtration techniques. Other protocols were also developed in order to collect and study sponge lectins, including screening of sponge genomes and expression in heterologous bacterial systems. The characterization of the lectins was performed by Edman degradation or mass spectrometry. Regarding their physiological roles, sponge lectins showed to be involved in morphogenesis and cell interaction, biomineralization and spiculogenesis, as well as host defense mechanisms and potentially in the association between the sponge and its microorganisms. In addition, these lectins exhibited a broad range of bioactivities, including modulation of inflammatory response, antimicrobial and cytotoxic activities, as well as anticancer and neuromodulatory activity. In view of their potential pharmacological applications, sponge lectins constitute promising molecules of biotechnological interest. PMID:26262628

  6. Purification and Characterization of Two Major Lectins from Araucaria brasiliensis syn. Araucaria angustifolia Seeds (Pinhão) 1

    PubMed Central

    Datta, Pradip K.; Figueroa, Maria O. D. C. R.; Lajolo, Franco M.

    1991-01-01

    Two major lectins (lectin I and lectin II) were purified to homogeneity from the seeds of Araucaria brasiliensis (Gymnospermae). The purity of the lectins was confirmed by polyacrylamide gel electrophoresis, isoelectric focusing, and high performance liquid chromatography. They are glycoproteins in nature containing 6.3 and 2.9%, respectively, of neutral sugar and have absorption coefficients of 3.8 and 4.7, respectively, at 280 nanometers. The molecular weights of both lectins obtained by gel filtration on Sephacryl S-400 were equal: 200,000. After dissociation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, molecular weights were 20,000 and 34,000, respectively, for lectin I and lectin II, suggesting they are decameric and hexameric in nature. The amino acid composition of both lectins showed little difference, but both had high amounts of acidic amino acids and lacked methionine in their molecule. The carbohydrate binding specificity of lectins was directed towards mannose, glucose, and their oligomers. High inhibitory activity was also found with thyroglobulin. The erythroagglutinating activity of the lectins was enhanced in the presence of high-molecular-weight substances both at 37 and 4°C. Divalent cations do not appear to be essential for activity. They maintained their agglutinating activity over a broad but different range of pH: 5.5 to 7.5 and 6.5 to 7.5, respectively. Both lectins agglutinated erythrocytes of human ABO blood types equally well. ImagesFigure 2Figure 3 PMID:16668523

  7. Lectin Activation in Giardia lamblia by Host Protease: A Novel Host-Parasite Interaction

    NASA Astrophysics Data System (ADS)

    Lev, Boaz; Ward, Honorine; Keusch, Gerald T.; Pereira, Miercio E. A.

    1986-04-01

    A lectin in Giardia lamblia was activated by secretions from the human duodenum, the environment where the parasite lives. Incubation of the secretions with trypsin inhibitors prevented the appearance of lectin activity, implicating proteases as the activating agent. Accordingly, lectin activation was also produced by crystalline trypsin and Pronase; other proteases tested were ineffective. When activated, the lectin agglutinated intestinal cells to which the parasite adheres in vivo. The lectin was most specific to mannose-6-phosphate and apparently was bound to the plasma membrane. Activation of a parasite lectin by a host protease represents a novel mechanism of hostparasite interaction and may contribute to the affinity of Giardia lamblia to the infection site.

  8. The Liverwort Contains a Lectin That Is Structurally and Evolutionary Related to the Monocot Mannose-Binding Lectins1

    PubMed Central

    Peumans, Willy J.; Barre, Annick; Bras, Julien; Rougé, Pierre; Proost, Paul; Van Damme, Els J.M.

    2002-01-01

    A mannose (Man)-binding lectin has been isolated and characterized from the thallus of the liverwort Marchantia polymorpha. N-terminal sequencing indicated that the M. polymorpha agglutinin (Marpola) shares sequence similarity with the superfamily of monocot Man-binding lectins. Searches in the databases yielded expressed sequence tags encoding Marpola. Sequence analysis, molecular modeling, and docking experiments revealed striking structural similarities between Marpola and the monocot Man-binding lectins. Activity and specificity studies further indicated that Marpola is a much stronger agglutinin than the Galanthus nivalis agglutinin and exhibits a preference for methylated Man and glucose, which is unprecedented within the family of monocot Man-binding lectins. The discovery of Marpola allows us, for the first time, to corroborate the evolutionary relationship between a lectin from a lower plant and a well-established lectin family from flowering plants. In addition, the identification of Marpola sheds a new light on the molecular evolution of the superfamily of monocot Man-binding lectins. Beside evolutionary considerations, the occurrence of a G. nivalis agglutinin homolog in a lower plant necessitates the rethinking of the physiological role of the whole family of monocot Man-binding lectins. PMID:12114560

  9. Enhancement of anti-Aeromonas salmonicida activity in Atlantic salmon (Salmo salar) macrophages by a mannose-binding lectin

    USGS Publications Warehouse

    Ottinger, C.A.; Johnson, S.C.; Ewart, K.V.; Brown, L.L.; Ross, N.W.

    1999-01-01

    We investigated the effects of a calcium-dependent mannose-binding lectin isolated from the serum of Atlantic salmon on Aeromonassalmonicida viability and the anti-A. salmonicida activity of Atlantic salmon macrophages. In the absence of other factors, binding of this lectin at concentrations of 0.8, 4.0 and 20.0 ng ml−1 to virulent A. salmonicida failed to significantly reduce (P>0.05) cell viability. However, binding of the lectin to A. salmonicida did result in significant (P≤0.05) dose-dependent increases in phagocytosis, and bactericidal activity. Significant increases (P≤0.05) were also observed in phagocyte respiratory burst activity within the lectin concentration range of 4.0–20.0 ng ml−1 but the stimulation was not dose dependent at these lectin concentrations. At the lowest lectin concentration tested (0.32 ng ml−1), a significant decrease (P≤0.05) in respiratory burst was observed. The structure and activity of this lectin are similar to that of mammalian mannose-binding lectins, which are known to play a pivotal role in innate immunity. The presence of this lectin may be an important defense mechanism against Gram-negative bacteria such as A. salmonicida.

  10. Lectins and their application to clinical microbiology.

    PubMed Central

    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 type blood cells and are used in a wide spectrum of applications, including, in part, as carriers of chemotherapeutic agents, as mitogens, for fractionation of animal cells, and for investigations of cellular surfaces. Numerous studies have shown that lectins can be used to identify rapidly certain microorganisms isolated from a clinical specimen or directly in a clinical specimen. Lectins have been demonstrated to be important diagnostic reagents in the major realms of clinical microbiology. Thus, they have been applied in bacteriology, mycology, mycobacteriology, and virology for the identification and/or differentiation of various microorganisms. Lectins have been used successfully as epidemiologic as well as taxonomic markers of specific microorganisms. Lectins provide the clinical microbiologist with cost-effective and potential diagnostic reagents. This review describes the applications of lectins in clinical microbiology. Images PMID:2200603

  11. A thermostable lectin from the rhizomes of Kaempferia parviflora.

    PubMed

    Konkumnerd, Wichchulada; Karnchanatat, Aphichart; Sangvanich, Polkit

    2010-08-30

    Kaempferia parviflora, or black galingale (Kra-Chai-Dam), belongs to the Zingiberaceae family and is used as both a food ingredient and a medicinal plant. There are diverse reports on the biological activities of compounds extracted from the plant, such as antimalarial, antifungal and an effective sexual-enhancing role, but not on the lectins. A lectin was isolated from the rhizomes of Kaempferia parviflora using affinity chromatography on Concanavalin A followed by gel filtration chromatography on Sephacryl S-100. The molecular weight of the purified lectin was about 41.7 kDa. This lectin showed haemagglutinating activity against erythrocytes from several sources, with the highest level being against those from rabbits. Moreover, the lectin was thermostable, with significant haemagglutinating activity detectable up to 75 degrees C. The results of trypsin digestion and liquid chromatography/tandem mass spectrometry analysis suggested that this protein could be a member of the lectin/endochitnase1 family. A lectin that showed thermotolerant haemagglutinating activity against erythrocytes from several sources was successfully purified from K. paviflora rhizomes. Peptide sequence analysis indicated that this lectin is similar to lectin/endochitinase 1 (Urtica dioica) or Hevein-like protein (Hevea brasiliensis). Copyright (c) 2010 Society of Chemical Industry.

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

    PubMed Central

    Hassan, Mohamed Ali Abol; Rouf, Razina; Tiralongo, Evelin; May, Tom W.; Tiralongo, Joe

    2015-01-01

    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. PMID:25856678

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

    PubMed

    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.

  14. Lectin cDNA and transgenic plants derived therefrom

    DOEpatents

    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.

  15. Purification and Characterization of a Lectin from Phaseolus vulgaris cv. (Anasazi Beans)

    PubMed Central

    Sharma, Arishya; Ng, Tzi Bun; Wong, Jack Ho; Lin, Peng

    2009-01-01

    A lectin has been isolated from seeds of the Phaseolus vulgaris cv. “Anasazi beans” using a procedure that involved affinity chromatography on Affi-gel blue gel, fast protein liquid chromatography (FPLC)-ion exchange chromatography on Mono S, and FPLC-gel filtration on Superdex 200. The lectin was comprised of two 30-kDa subunits with substantial N-terminal sequence similarity to other Phaseolus lectins. The hemagglutinating activity of the lectin was stable within the pH range of 1–14 and the temperature range of 0–80°C. The lectin potently suppressed proliferation of MCF-7 (breast cancer) cells with an IC50 of 1.3 μM, and inhibited the activity of HIV-1 reverse transcriptase with an IC50 of 7.6 μM. The lectin evoked a mitogenic response from murine splenocytes as evidenced by an increase in [3H-methyl]-thymidine incorporation. The lectin had no antifungal activity. It did not stimulate nitric oxide production by murine peritoneal macrophages. Chemical modification results indicated that tryptophan was crucial for the hemagglutinating activity of the lectin. PMID:19343172

  16. A Glucosamine-Specific Lectin from Green Dragon No. 8 Beans (Phaseolus vulgaris) Induced Apoptosis on Nasopharyngeal Carcinoma Cells

    PubMed Central

    Chan, Yau Sang; Xia, Lixin; Ng, Tzi Bun

    2015-01-01

    A lectin exhibiting antiproliferative activity on tumor cell lines but devoid of antifungal activity has been purified from Phaseolus vulgaris cv. Green Dragon no. 8 seeds. The lectin was a 60 kDa dimeric protein with two 30 kDa subunits. It was a glucosamine-specific lectin as implied from the inhibitory effect of glucosamine on hemagglutinating activity of the lectin. The steps for isolation of the lectin involved Affi-gel blue gel (affinity gel), Mono Q (anion exchanger), and Superdex 75 column (size exclusion). The lectin was purified 20.8-fold from the crude extract of the beans. The purified lectin showed antiproliferative activity on breast cancer MCF7 cell line and nasopharyngeal cancer HONE1 and CNE2 cell lines, but a low activity on normal skin fibroblast HSF98 cell line. The lectin was shown to induce apoptosis on HONE1 cells, as indicated by increased phosphatidylserine externalization and mitochondrial depolarization. It also blocked HONE1 cell division and kept the cells at the G2/M phase of the cell cycle. PMID:26290674

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

    PubMed

    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.

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

    PubMed

    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.

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

    PubMed

    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 http://proline.physics.iisc.ernet.in/cancerdb .

  20. Innate Immunity in Lobsters: Partial Purification and Characterization of a Panulirus cygnus Anti-A Lectin.

    PubMed

    Flower, Robert L P

    2012-01-01

    A lectin detected in haemolymph from the Australian spiny lobster Panulirus cygnus agglutinated human ABO Group A cells to a higher titre than Group O or B. The lectin also agglutinated rat and sheep erythrocytes, with reactivity with rat erythrocytes strongly enhanced by treatment with the proteolytic enzyme papain, an observation consistent with reactivity via a glycolipid. The lectin, purified by affinity chromatography on fixed rat-erythrocyte stroma, was inhibited equally by N-acetylglucosamine and N-acetylgalactosamine. Comparison of data from gel filtration of haemolymph (behaving as a 1,800,000 Da macromolecule), and polyacrylamide gel electrophoresis of purified lectin (a single 67,000 Da band), suggested that in haemolymph the lecin was a multimer. The purified anti-A lectin autoprecipitated unless the storage solution contained chaotropic inhibitors (125 mmol/L sucrose: 500 mmol/L urea). The properties of this anti-A lectin and other similar lectins are consistent with a role in innate immunity in these invertebrates.

  1. Lectin-Array Blotting.

    PubMed

    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.

  2. Fungal lectins: a growing family.

    PubMed

    Kobayashi, Yuka; Kawagishi, Hirokazu

    2014-01-01

    Fungi are members of a large group of eukaryotic organisms that include yeasts and molds, as well as the most familiar member, mushrooms. Fungal lectins with unique specificity and structures have been discovered. In general, fungal lectins are classified into specific families based on their amino acid sequences and three-dimensional structures. In this chapter, we provide an overview of the approximately 80 types of mushroom and fungal lectins that have been isolated and studied to date. In particular, we have focused on ten fungal lectins (Agaricus bisporus, Agrocybe cylindracea, Aleuria aurantia, Aspergillus oryzae, Clitocybe nebularis, Marasmius oreades, Psathyrella velutina, Rhizopus stolonifer, Pholiota squarrosa, Polyporus squamosus), many of which are commercially available and their properties, sugar-binding specificities, structural grouping into families, and applications for biological research being described. The sialic acid-specific lectins (Agrocybe cylindracea and Polyporus squamosus) and fucose-specific lectins (Aleuria aurantia, Aspergillus oryzae, Rhizopus stolonifer, and Pholiota squarrosa) each showed potential for use in identifying sialic acid glycoconjugates and fucose glycoconjugates. Although not much is currently known about fungal lectins compared to animal and plant lectins, the knowledge accumulated thus far shows great promise for several applications in the fields of taxonomy, biomedicine, and molecular and cellular biology.

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

    PubMed

    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.

  4. Lectins interact differentially with purified human eosinophils, cultured cord blood-derived mast cells and the myeloid leukaemic cell line AML14.3D10: induction of interleukin-4 secretion is conserved among granulocytes, but is not proportional to agglutination or lectin-glycoprotein interaction.

    PubMed

    Hoffmann, H J; Dahl, C; Schiøtz, P O; Berglund, L; Dahl, R

    2003-07-01

    Atopy is closely associated with the cellular T helper type-2 (Th2) phenotype, that is dominated by the pleiotrophic cytokine IL-4. The cellular source of IL-4 has yet to be determined, although basophils have been proposed. Eosinophils and mast cells are likely contenders investigated here, and the eosinophil-like leukaemia line AML14.3D10 is compared to eosinophils as an in vitro culturable model for eosinophils. Lectins can cross-link-specific surface glycoproteins and are found in the ingested (processed foods) and inhaled (airborne pollen grains) human environment. Therefore it is of interest to determine whether lectins can elicit the release of IL-4 from Th2-associated granulocytes other than basophils. This study investigated the ability of eosinophils, AML14.3D10 and mast cells to secrete preformed IL-4 in response to stimulation with lectins, and explored molecular mechanisms underlying the interaction. Purified eosinophils and basophils, and cultured mast cells and AML14.3D10 cells were incubated with 1 micro m lectin. Agglutination was scored by microscopy. IL-4 secretion was measured by enzyme-linked immunosorbent assay. Biotinylated lectins were used to determine binding to cells by flow cytometry and in lectin blots of sodium dodecyl sulphate (SDS) gels. Purified human eosinophils, AML14.3D10 cells and cultured mast cells secrete IL-4 with a pattern similar to that found in basophils when stimulated with a panel of reactive and unreactive lectins. The lectin SNA induces IL-4 secretion from mast cells and basophils, but not from eosinophils or AML14.3D10. Eosinophils appear to secrete only pre-formed IL-4, whereas mast cells may synthesize IL-4 on ligation with the lectin LCA. Lectins that agglutinate the granulocytes investigated do not necessarily induce secretion of IL-4. Lectins that elicit secretion of IL-4 bind more to eosinophils than unreactive lectins as determined by flow cytometry and lectin blotting of SDS gels. As granulocytes with functions related to that of basophils, eosinophils, AML14.3D10 and cultured mast cells respond to stimulation with lectins similarly to basophils. This emphasizes the possibility that eosinophils and mast cells may be linked in their cellular heritage as the cellular partners, and lectins as ligands, may contribute to the maintenance of a Th2-favoured microenvironment that is thought to underlie the allergic march.

  5. Plant lectins: the ties that bind in root symbiosis and plant defense.

    PubMed

    De Hoff, Peter L; Brill, Laurence M; Hirsch, Ann M

    2009-07-01

    Lectins are a diverse group of carbohydrate-binding proteins that are found within and associated with organisms from all kingdoms of life. Several different classes of plant lectins serve a diverse array of functions. The most prominent of these include participation in plant defense against predators and pathogens and involvement in symbiotic interactions between host plants and symbiotic microbes, including mycorrhizal fungi and nitrogen-fixing rhizobia. Extensive biological, biochemical, and molecular studies have shed light on the functions of plant lectins, and a plethora of uncharacterized lectin genes are being revealed at the genomic scale, suggesting unexplored and novel diversity in plant lectin structure and function. Integration of the results from these different types of research is beginning to yield a more detailed understanding of the function of lectins in symbiosis, defense, and plant biology in general.

  6. Synthesis and optimization of lectin functionalized nanoprobes for the selective recovery of glycoproteins from human body fluids.

    PubMed

    Ferreira, José A; Daniel-da-Silva, Ana Luísa; Alves, Renato M P; Duarte, Daniel; Vieira, Igor; Santos, Lúcio Lara; Vitorino, Rui; Amado, Francisco

    2011-09-15

    Biomedical sciences, and in particular biomarker research, demand efficient glycoprotein enrichment platforms. Herein magnetic nanoprobes (MNP), after being coated with three broad-spectrum lectins-concanavalin A (ConA), wheat germ agglutinin (WGA), and Maackia amurensis lectin (MA)-were utilized to selectively capture glycoproteins from human body fluids. Additionally, a new methodology, based on protection of the lectins with their target sugars prior to coupling with MNPs, was proposed to overcome the nonspecific nature of conjugation. This approach contributed to preserve lectin conformation, increasing by 40% and 90% the affinity of ConA and MA for glycoproteins in relation to synthesis with nonprotected lectins. Optimal operating conditions (temperature, time) and maximum binding capacities were further determined for each lectin by use of fetuin as a reference. The enhanced performance of lectin-based nanoplatforms was demonstrated by comparing MNP@ConA with conventional Sepharose@ConA. These experiments have shown that ConA immobilized on MNP exhibited 5 times higher affinity for fetuin and ovalbumin when compared with Sepharose@ConA with the same amount of immobilized lectin. MNP@Lectins were then applied to human serum, saliva, and urine and the recovered proteins were digested with trypsin and analyzed by nano-HPLC MALDI-TOF/TOF. This allowed the identification of 180 proteins, 90% of which were found to be glycosylated by use of bioinformatics tools, therefore revealing low levels of unspecific binding. Thus, MNP@lectins have proved to be a valuable tool for glycoproteomic studies, particularly when dealing with minute amounts of material.

  7. Selective binding of lectins to normal and neoplastic urothelium in rat and mouse bladder carcinogenesis models.

    PubMed

    Zupančič, Daša; Kreft, Mateja Erdani; Romih, Rok

    2014-01-01

    Bladder cancer adjuvant intravesical therapy could be optimized by more selective targeting of neoplastic tissue via specific binding of lectins to plasma membrane carbohydrates. Our aim was to establish rat and mouse models of bladder carcinogenesis to investigate in vivo and ex vivo binding of selected lectins to the luminal surface of normal and neoplastic urothelium. Male rats and mice were treated with 0.05 % N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in drinking water and used for ex vivo and in vivo lectin binding experiments. Urinary bladder samples were also used for paraffin embedding, scanning electron microscopy and immunofluorescence labelling of uroplakins. During carcinogenesis, the structure of the urinary bladder luminal surface changed from microridges to microvilli and ropy ridges and the expression of urothelial-specific glycoproteins uroplakins was decreased. Ex vivo and in vivo lectin binding experiments gave comparable results. Jacalin (lectin from Artocarpus integrifolia) exhibited the highest selectivity for neoplastic compared to normal urothelium of rats and mice. The binding of lectin from Amaranthus caudatus decreased in rat model and increased in mouse carcinogenesis model, indicating interspecies variations of plasma membrane glycosylation. Lectin from Datura stramonium showed higher affinity for neoplastic urothelium compared to the normal in rat and mouse model. The BBN-induced animal models of bladder carcinogenesis offer a promising approach for lectin binding experiments and further lectin-mediated targeted drug delivery research. Moreover, in vivo lectin binding experiments are comparable to ex vivo experiments, which should be considered when planning and optimizing future research.

  8. Lectin activity in mycelial extracts of Fusarium species.

    PubMed

    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.

  9. Effects of environmental factors on C-type lectin recognition to zooxanthellae in the stony coral Pocillopora damicornis.

    PubMed

    Zhou, Zhi; Zhao, Shuimiao; Ni, Junyi; Su, Yilu; Wang, Lingui; Xu, Yanlai

    2018-08-01

    C-type lectin is a superfamily of Ca 2+ -dependent carbohydrate-recognition proteins that play significant roles in nonself-recognition and pathogen clearance. In the present study, a C-type lectin (PdC-Lectin) was chosen from stony coral Pocillopora damicornis to understand its recognition characteristics to zooxanthellae. PdC-Lectin protein contained a signal peptide and a carbohydrate-recognition domain with EPN motif in Ca 2+ -binding site 2. The PdC-Lectin recombinant protein was expressed and purified in vitro. The binding of PdC-Lectin protein to zooxanthellae was determined with western blotting method, and the bound protein to 10-10 5  cell mL -1 zooxanthellae was detectable in a concentration-dependent manner. Less PdC-Lectin protein binding to zooxanthellae was observed for the incubation at 36 °C than that at 26 °C. Furthermore, the PAMP recognition spectrum of PdC-Lectin protein was tested through surface plasmon resonance method, and it bound to LPS and Lipid A, but not to LTA, β-glucan, mannose or Poly (I:C). When PdC-Lectin protein was preincubated with LPS, there was less protein binding to zooxanthellae compared with that in non-preincubation group. These results collectively suggest that PdC-Lectin could recognize zooxanthellae, and the recognition could be repressed by high temperature and pathogenic bacteria, which would help to further understand the molecular mechanism of coral bleaching and the establishment of coral-zooxanthella symbiosis in the stony coral P. damicornis. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Deterrent activity of plant lectins on cowpea weevil Callosobruchus maculatus (F.) oviposition.

    PubMed

    Sadeghi, Amin; Van Damme, Els J M; Peumans, Willy J; Smagghe, Guy

    2006-09-01

    A set of 14 plant lectins was screened in a binary choice bioassay for inhibitory activity on cowpea weevil Callosobruchus maculatus (F.) oviposition. Coating of chickpea seeds (Cicer arietinum L.) with a 0.05% (w/v) solution of plant lectins caused a significant reduction in egg laying. Control experiments with heat inactivated lectin and BSA indicated that the observed deterrent effects are specific and require carbohydrate-binding activity. However, no clear correlation could be established between deterrent activity and sugar-binding specificity/molecular structure of the lectins. Increasing the insect density reduced the inhibitory effect of the lectins confirming that female insects are capable of adjusting their oviposition rates as a function of host availability.

  11. Graphene oxide-based electrochemical label-free detection of glycoproteins down to aM level using a lectin biosensor

    PubMed Central

    Klukova, L.; Filip, J.; Belicky, S.; Vikartovska, A.; Tkac, J.

    2017-01-01

    A label-free ultrasensitive impedimetric biosensor with lectin immobilised on graphene oxide (GO) for the detection of glycoproteins from 1 aM is shown here. This is the first time a functional lectin biosensor with lectin directly immobilised on a graphene-based interface without any polymer modifier has been described. The study also shows that hydrophilic oxidative debris present on GO has a beneficial effect on the sensitivity of (8.46 ± 0.20)% per decade for the lectin biosensor compared to the sensitivity of (4.52 ± 0.23)% per decade for the lectin biosensor built up from GO with the oxidative debris washed out. PMID:27277703

  12. Electronic Detection of Lectins Using Carbohydrate Functionalized Nanostructures: Graphene versus Carbon Nanotubes

    PubMed Central

    Chen, Yanan; Vedala, Harindra; Kotchey, Gregg P.; Audfray, Aymeric; Cecioni, Samy; Imberty, Anne; Vidal, Sébastien; Star, Alexander

    2012-01-01

    Here we investigated the interactions between lectins and carbohydrates using field-effect transistor (FET) devices comprised of chemically converted graphene (CCG) and single-walled carbon nanotubes (SWNTs). Pyrene- and porphyrin-based glycoconjugates were functionalized noncovalently on the surface of CCG-FET and SWNT-FET devices, which were then treated with 2 µM of nonspecific and specific lectins. In particular, three different lectins (PA-IL, PA-IIL and ConA) and three carbohydrate epitopes (galactose, fucose and mannose) were tested. The responses of 36 different devices were compared and rationalized using computer-aided models of carbon nanostructure/glycoconjugate interactions. Glycoconjugates surface coverage in addition to one-dimensional structures of SWNTs resulted in optimal lectin detection. Additionally, lectin titration data of SWNT- and CCG-based biosensors were used to calculate lectin dissociation constants (Kd) and compare them to the values obtained from the isothermal titration microcalorimetry (ITC) technique. PMID:22136380

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

    PubMed

    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.

  14. Lectins from Mycelia of Basidiomycetes

    PubMed Central

    Nikitina, Valentina E.; Loshchinina, Ekaterina A.; Vetchinkina, Elena P.

    2017-01-01

    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. PMID:28640205

  15. Lectins in fish skin: do they play a role in host-monogenean interactions?

    PubMed

    Buchmann, K

    2001-09-01

    Mucus samples from rainbow trout skin with or without infections by Gyrodactylus derjavini were tested for the presence of lectins reacting with mannose, galactose and lactose. The samples inhibited the binding of biotinylated lectins (from Canavalia ensiformis, Artocarpus integrifolia and Erythrina corallodendron, respectively) to microtitre plates with covalently bound carbohydrates (mannopyranoside, galactopyranoside and lactose, respectively). However, the inhibition of C. ensiformis and A. integrifolia lectins was slightly greater when mucus from infected (but recovering) fish was used, suggesting an increase of mannose and galactose binding lectins in fish skin exposed to parasites. As mannose, galactose and lactose are present on the glycocalyx of Gyrodactylus derjavini, it is suggested that lectins could play a dual role in interactions between fish hosts and their monogenean parasites. Thus, recognition between parasite and host and also host responses towards parasite infections could both, at least partly, involve carbohydrate-lectin binding.

  16. Isolation and molecular characterization of two lectins from dwarf elder (Sambucus ebulus L.) blossoms related to the Sam n1 allergen.

    PubMed

    Jimenez, Pilar; Cabrero, Patricia; Basterrechea, José E; Tejero, Jesús; Cordoba-Diaz, Damian; Girbes, Tomas

    2013-10-14

    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.

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

    PubMed Central

    Jimenez, Pilar; Cabrero, Patricia; Basterrechea, José E.; Tejero, Jesús; Cordoba-Diaz, Damian; Girbes, Tomas

    2013-01-01

    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. PMID:24129061

  18. In-house preparation of lectin panel and detection of Tn polyagglutination.

    PubMed

    Das, Sudipta Sekhar

    2015-01-01

    Polyagglutination is a condition in which red cells are agglutinated by ABO-compatible adult human sera, but not by cord blood sera and may be acquired or inherited. Lectins are invaluable reagents in the investigation of red cells polyagglutination. We prepared in-house lectin panel and confirmed Tn polyagglutination in a pregnant lady. The lady was anemic and refused blood transfusion elsewhere due to serological discrepancy. We found ABO discrepancy and an incompatible minor cross-match in the initial investigation and suspected polyagglutination. Confirmation of polyagglutination was done using adult and cord sera. We then used the in-house lectin panels to detect the type of polyagglutination. The agglutination pattern with the various lectins was suggestive of Tn polyagglutination, which was further supported by the enzyme study. Most blood banks in India lack commercial lectin panels because of cost and procurement difficulty. Lectins play an important role in the diagnosis and differentiation of polyagglutination and immunohematological management of patient. The important and basic lectins can be prepared in-house using specific raw seeds following standardized protocol.

  19. Plant lectins as defense proteins against phytophagous insects.

    PubMed

    Vandenborre, Gianni; Smagghe, Guy; Van Damme, Els J M

    2011-09-01

    One of the most important direct defense responses in plants against the attack by phytophagous insects is the production of insecticidal peptides or proteins. One particular class of entomotoxic proteins present in many plant species is the group of carbohydrate-binding proteins or lectins. During the last decade a lot of progress was made in the study of a few lectins that are expressed in response to herbivory by phytophagous insects and the insecticidal properties of plant lectins in general. This review gives an overview of lectins with high potential for the use in pest control strategies based on their activity towards pest insects. In addition, potential target sites for lectins inside the insect and the mode of action are discussed. In addition, the effect of plant lectins on non-target organisms such as beneficial insects as well as on human/animal consumers is discussed. It can be concluded that some insecticidal lectins are useful tools that can contribute to the development of integrated pest management strategies with minimal effect(s) on non-target organisms. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

    PubMed

    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.

  1. Effects of some plant lectins on hydrogen peroxide release from macrophages induced with streptococcal preparation OK-432.

    PubMed Central

    Tomioka, H; Saito, H

    1980-01-01

    Concanavalin A and phytohemagglutinin were found to cause marked inhibition of H2O2 release from macrophages induced with killed streptococci (preparation OK-432). The inhibitory effect of these two lectins on the H2O2 release from macrophages was observed with spontaneous and wheat germ lectin-triggered H2O2 release. This suggests that the lectins act directly on the macrophage H2O2-releasing function, per se, but not on the wheat germ lectin-H2O2 release-enhancing process. Concanavalin A exhibited its inhibitory action on macrophage H2O2 release by specific binding to D-mannopyranoside receptor sites on the macrophage cell surface. Galactose-binding lectins, peanut agglutinin, and soybean agglutinin failed to inhibit, but, on the other hand, slightly enhanced macrophage H2O2 release. The effect of these five lectins on the phagocytosis of latex particles by macrophages was tested. Wheat germ lectin, concanavalin A, and phytohemagglutinin significantly depressed the macrophage phagocytosis, whereas peanut agglutinin and soybean agglutinin failed to show any inhibitory action. PMID:7399666

  2. The Distribution of Lectins across the Phylum Nematoda: A Genome-Wide Search

    PubMed Central

    Bauters, Lander; Naalden, Diana; Gheysen, Godelieve

    2017-01-01

    Nematodes are a very diverse phylum that has adapted to nearly every ecosystem. They have developed specialized lifestyles, dividing the phylum into free-living, animal, and plant parasitic species. Their sheer abundance in numbers and presence in nearly every ecosystem make them the most prevalent animals on earth. In this research nematode-specific profiles were designed to retrieve predicted lectin-like domains from the sequence data of nematode genomes and transcriptomes. Lectins are carbohydrate-binding proteins that play numerous roles inside and outside the cell depending on their sugar specificity and associated protein domains. The sugar-binding properties of the retrieved lectin-like proteins were predicted in silico. Although most research has focused on C-type lectin-like, galectin-like, and calreticulin-like proteins in nematodes, we show that the lectin-like repertoire in nematodes is far more diverse. We focused on C-type lectins, which are abundantly present in all investigated nematode species, but seem to be far more abundant in free-living species. Although C-type lectin-like proteins are omnipresent in nematodes, we have shown that only a small part possesses the residues that are thought to be essential for carbohydrate binding. Curiously, hevein, a typical plant lectin domain not reported in animals before, was found in some nematode species. PMID:28054982

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

    PubMed Central

    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

  4. The Distribution of Lectins across the Phylum Nematoda: A Genome-Wide Search.

    PubMed

    Bauters, Lander; Naalden, Diana; Gheysen, Godelieve

    2017-01-04

    Nematodes are a very diverse phylum that has adapted to nearly every ecosystem. They have developed specialized lifestyles, dividing the phylum into free-living, animal, and plant parasitic species. Their sheer abundance in numbers and presence in nearly every ecosystem make them the most prevalent animals on earth. In this research nematode-specific profiles were designed to retrieve predicted lectin-like domains from the sequence data of nematode genomes and transcriptomes. Lectins are carbohydrate-binding proteins that play numerous roles inside and outside the cell depending on their sugar specificity and associated protein domains. The sugar-binding properties of the retrieved lectin-like proteins were predicted in silico. Although most research has focused on C-type lectin-like, galectin-like, and calreticulin-like proteins in nematodes, we show that the lectin-like repertoire in nematodes is far more diverse. We focused on C-type lectins, which are abundantly present in all investigated nematode species, but seem to be far more abundant in free-living species. Although C-type lectin-like proteins are omnipresent in nematodes, we have shown that only a small part possesses the residues that are thought to be essential for carbohydrate binding. Curiously, hevein, a typical plant lectin domain not reported in animals before, was found in some nematode species.

  5. [Lectins from Sambucus nigra L inflorescences: isolation and investigation of biological activity using procaryotic test-systems].

    PubMed

    Karpova, I S; Korets'ka, N V; Pal'chykovs'ka, L H; Nehruts'ka, V V

    2007-01-01

    Isolation of lectins from extracts of the Sambucus nigra inflorescences and of pollen material have been performed using isoelectric focusing without carrier ampholytes (autofocusing). Fractions active in agglutination tests with different carbohydrate specificity were subjected to SDS-PAGE. The major lectin found in whole inflores-cences was GalNAc specific and is proposed to be a heterotetramer with subunits of about 30 and 33 kDa. It was called SNAflu-I. At least two other lectins were present in the pollen material and supposed to consist of identical subunits. Major positively charged lectin was Glc/Man specific with subunit of 26 kDa and called SNApol-I. Other pollen component (SNApol-II) was Gal specific with subunit of about 20 kDa. In order to elucidate cell targets sensitive for the S. nigra lectin's activity the combined effects of the lectins and transcriptional of phenazine origin on B. subtilis cells growth have been studied. Only SNApol-I demonstrated the antagonistic activity against these inhibitors in vivo. This lectin but not the SNAflu-I can also inhibit transcription in vitro. It is supposed that lectins from the same source may act in different directions on cell metabolism. Particularly one of the common targets may be the DNA-dependent synthesis of RNA.

  6. Responsive Photonic Crystal Carbohydrate Hydrogel Sensor Materials for Selective and Sensitive Lectin Protein Detection.

    PubMed

    Cai, Zhongyu; Sasmal, Aniruddha; Liu, Xinyu; Asher, Sanford A

    2017-10-27

    Lectin proteins, such as the highly toxic lectin protein, ricin, and the immunochemically important lectin, jacalin, play significant roles in many biological functions. It is highly desirable to develop a simple but efficient method to selectively detect lectin proteins. Here we report the development of carbohydrate containing responsive hydrogel sensing materials for the selective detection of lectin proteins. The copolymerization of a vinyl linked carbohydrate monomer with acrylamide and acrylic acid forms a carbohydrate hydrogel that shows specific "multivalent" binding to lectin proteins. The resulting carbohydrate hydrogels are attached to 2-D photonic crystals (PCs) that brightly diffract visible light. This diffraction provides an optical readout that sensitively monitors the hydrogel volume. We utilize lactose, galactose, and mannose containing hydrogels to fabricate a series of 2-D PC sensors that show strong selective binding to the lectin proteins ricin, jacalin, and concanavalin A (Con A). This binding causes a carbohydrate hydrogel shrinkage which significantly shifts the diffraction wavelength. The resulting 2-D PC sensors can selectively detect the lectin proteins ricin, jacalin, and Con A. These unoptimized 2-D PC hydrogel sensors show a limit of detection (LoD) of 7.5 × 10 -8 M for ricin, a LoD of 2.3 × 10 -7 M for jacalin, and a LoD of 3.8 × 10 -8 M for Con A, respectively. This sensor fabrication approach may enable numerous sensors for the selective detection of numerous lectin proteins.

  7. Effects of Lectins on initial attachment of cariogenic Streptococcus mutans.

    PubMed

    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.

  8. Targeted delivery of antigen to hamster nasal lymphoid tissue with M-cell-directed lectins.

    PubMed Central

    Giannasca, P J; Boden, J A; Monath, T P

    1997-01-01

    The nasal cavity of a rodent is lined by an epithelium organized into distinct regional domains responsible for specific physiological functions. Aggregates of nasal lymphoid tissue (NALT) located at the base of the nasal cavity are believed to be sites of induction of mucosal immune responses to airborne antigens. The epithelium overlying NALT contains M cells which are specialized for the transcytosis of immunogens, as demonstrated in other mucosal tissues. We hypothesized that NALT M cells are characterized by distinct glycoconjugate receptors which influence antigen uptake and immune responses to transcytosed antigens. To identify glycoconjugates that may distinguish NALT M cells from other cells of the respiratory epithelium (RE), we performed lectin histochemistry on sections of the hamster nasal cavity with a panel of lectins. Many classes of glycoconjugates were found on epithelial cells in this region. While most lectins bound to sites on both the RE and M cells, probes capable of recognizing alpha-linked galactose were found to label the follicle-associated epithelium (FAE) almost exclusively. By morphological criteria, the FAE contains >90% M cells. To determine if apical glycoconjugates on M cells were accessible from the nasal cavity, an M-cell-selective lectin and a control lectin in parallel were administered intranasally to hamsters. The M-cell-selective lectin was found to specifically target the FAE, while the control lectin did not. Lectin bound to M cells in vivo was efficiently endocytosed, consistent with the role of M cells in antigen transport. Intranasal immunization with lectin-test antigen conjugates without adjuvant stimulated induction of specific serum immunoglobulin G, whereas antigen alone or admixed with lectin did not. The selective recognition of NALT M cells by a lectin in vivo provides a model for microbial adhesin-host cell receptor interactions on M cells and the targeted delivery of immunogens to NALT following intranasal administration. PMID:9317039

  9. beta-Galactoside-binding muscle lectins of man and monkey show antigenic cross-reactions with those of bovine origin.

    PubMed Central

    Childs, R A; Feizi, T

    1979-01-01

    Endogenous beta-galactoside-binding lectins were isolated from human heart and from human and rhesus-monkey skeletal muscles. Gel precipitation and radioimmunoassays with rabbit antisera to calf heart lectin revealed antigenic cross-reactions between the primate and bovine muscle lectins. Images Fig. 1. Fig. 2. PMID:120198

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

    PubMed

    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.

  11. Surface Glycosylation Profiles of Urine Extracellular Vesicles

    PubMed Central

    Gerlach, Jared Q.; Krüger, Anja; Gallogly, Susan; Hanley, Shirley A.; Hogan, Marie C.; Ward, Christopher J.

    2013-01-01

    Urinary extracellular vesicles (uEVs) are released by cells throughout the nephron and contain biomolecules from their cells of origin. Although uEV-associated proteins and RNA have been studied in detail, little information exists regarding uEV glycosylation characteristics. Surface glycosylation profiling by flow cytometry and lectin microarray was applied to uEVs enriched from urine of healthy adults by ultracentrifugation and centrifugal filtration. The carbohydrate specificity of lectin microarray profiles was confirmed by competitive sugar inhibition and carbohydrate-specific enzyme hydrolysis. Glycosylation profiles of uEVs and purified Tamm Horsfall protein were compared. In both flow cytometry and lectin microarray assays, uEVs demonstrated surface binding, at low to moderate intensities, of a broad range of lectins whether prepared by ultracentrifugation or centrifugal filtration. In general, ultracentrifugation-prepared uEVs demonstrated higher lectin binding intensities than centrifugal filtration-prepared uEVs consistent with lesser amounts of co-purified non-vesicular proteins. The surface glycosylation profiles of uEVs showed little inter-individual variation and were distinct from those of Tamm Horsfall protein, which bound a limited number of lectins. In a pilot study, lectin microarray was used to compare uEVs from individuals with autosomal dominant polycystic kidney disease to those of age-matched controls. The lectin microarray profiles of polycystic kidney disease and healthy uEVs showed differences in binding intensity of 6/43 lectins. Our results reveal a complex surface glycosylation profile of uEVs that is accessible to lectin-based analysis following multiple uEV enrichment techniques, is distinct from co-purified Tamm Horsfall protein and may demonstrate disease-specific modifications. PMID:24069349

  12. Quantitative evaluation of lectin-reactive glycoforms of α(1)-acid glycoprotein using lectin affinity capillary electrophoresis with fluorescence detection.

    PubMed

    Shimura, Kiyohito; Tamura, Mayumi; Toda, Tosifusa; Yazawa, Shin; Kasai, Ken-ichi

    2011-08-01

    α(1)-Acid glycoprotein (AGP) was previously shown to be a marker candidate of disease progression and prognosis of patients with malignancies by analysis of its glycoforms via lectins. Herein, affinity capillary electrophoresis of fluorescein-labeled AGP using lectins with the aid of laser-induced fluorescence detection was developed for quantitative evaluation of the fractional ratios of concanavalin A-reactive or Aleuria aurantia lectin-reactive AGP. Labeled AGP was applied at the anodic end of a fused-silica capillary (50 μm id, 360 μm od, 27 cm long) coated with linear polyacryloyl-β-alanyl-β-alanine, and electrophoresis was carried out for about 10 min in 60 mM 3-morpholinopropane-1-sulfonic acid-NaOH buffer (pH 7.35). Addition of the lectins to the anode buffer resulted in the separation of lectin-reactive glycoform peaks from lectin-non-reactive glycoform peaks. Quantification of the peak area of each group revealed that the percent of lectin-reactive AGP is independent of a labeling ratio ranging from 0.4 to 1.5 mol fluorescein/mol AGP, i.e. the standard deviation of 0.5% for an average of 59.9% (n=3). In combination with a facile procedure for micro-purification of AGP from serum, the present procedure, marking the reactivity of AGP with lectins, should be useful in determining the prognosis for a large number of patients with malignancies. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Functional Mapping of the Lectin Activity Site on the β-Prism Domain of Vibrio cholerae Cytolysin

    PubMed Central

    Rai, Anand Kumar; Paul, Karan; Chattopadhyay, Kausik

    2013-01-01

    Vibrio cholerae cytolysin (VCC) is a prominent member in the family of β-barrel pore-forming toxins. It induces lysis of target eukaryotic cells by forming transmembrane oligomeric β-barrel channels. VCC also exhibits prominent lectin-like activity in interacting with β1-galactosyl-terminated glycoconjugates. Apart from the cytolysin domain, VCC harbors two lectin-like domains: the β-Trefoil and the β-Prism domains; however, precise contribution of these domains in the lectin property of VCC is not known. Also, role(s) of these lectin-like domains in the mode of action of VCC remain obscure. In the present study, we show that the β-Prism domain of VCC acts as the structural scaffold to determine the lectin activity of the protein toward β1-galactosyl-terminated glycoconjugates. Toward exploring the physiological implication of the β-Prism domain, we demonstrate that the presence of the β-Prism domain-mediated lectin activity is crucial for an efficient interaction of the toxin toward the target cells. Our results also suggest that such lectin activity may act to regulate the oligomerization ability of the membrane-bound VCC toxin. Based on the data presented here, and also consistent with the existing structural information, we propose a novel mechanism of regulation imposed by the β-Prism domain's lectin activity, implicated in the process of membrane pore formation by VCC. PMID:23209283

  14. Fluorescence Lectin Bar-Coding of Glycoconjugates in the Extracellular Matrix of Biofilm and Bioaggregate Forming Microorganisms.

    PubMed

    Neu, Thomas R; Kuhlicke, Ute

    2017-02-10

    Microbial biofilm systems are defined as interface-associated microorganisms embedded into a self-produced matrix. The extracellular matrix represents a continuous challenge in terms of characterization and analysis. The tools applied in more detailed studies comprise extraction/chemical analysis, molecular characterization, and visualisation using various techniques. Imaging by laser microscopy became a standard tool for biofilm analysis, and, in combination with fluorescently labelled lectins, the glycoconjugates of the matrix can be assessed. By employing this approach a wide range of pure culture biofilms from different habitats were examined using the commercially available lectins. From the results, a binary barcode pattern of lectin binding can be generated. Furthermore, the results can be fine-tuned and transferred into a heat map according to signal intensity. The lectin barcode approach is suggested as a useful tool for investigating the biofilm matrix characteristics and dynamics at various levels, e.g. bacterial cell surfaces, adhesive footprints, individual microcolonies, and the gross biofilm or bio-aggregate. Hence fluorescence lectin bar-coding (FLBC) serves as a basis for a subsequent tailor-made fluorescence lectin-binding analysis (FLBA) of a particular biofilm. So far, the lectin approach represents the only tool for in situ characterization of the glycoconjugate makeup in biofilm systems.  Furthermore, lectin staining lends itself to other fluorescence techniques in order to correlate it with cellular biofilm constituents in general and glycoconjugate producers in particular.

  15. The bark of Robinia pseudoacacia contains a complex mixture of lectins.Characterization of the proteins and the cDNA clones.

    PubMed Central

    Van Damme, E J; Barre, A; Smeets, K; Torrekens, S; Van Leuven, F; Rougé, P; Peumans, W J

    1995-01-01

    Two lectins were isolated from the inner bark of Robinia pseudoacacia (black locust). The first (and major) lectin (called RPbAI) is composed of five isolectins that originate from the association of 31.5- and 29-kD polypeptides into tetramers. In contrast, the second (minor) lectin (called RPbAII) is a hometetramer composed of 26-kD subunits. The cDNA clones encoding the polypeptides of RPbAI and RPbAII were isolated and their sequences determined. Apparently all three polypeptides are translated from mRNAs of approximately 1.2 kb. Alignment of the deduced amino acid sequences of the different clones indicates that the 31.5- and 29-kD RPbAI polypeptides show approximately 80% sequence identity and are homologous to the previously reported legume seed lectins, whereas the 26-kD RPbAII polypeptide shows only 33% sequence identity to the previously described legume lectins. Modeling the 31.5-kD subunit of RPbAI predicts that its three-dimensional structure is strongly related to the three-dimensional models that have been determined thus far for a few legume lectins. Southern blot analysis of genomic DNA isolated from Robinia has revealed that the Robinia bark lectins are the result of the expression of a small family of lectin genes. PMID:7716244

  16. Termiticidal lectins from Myracrodruon urundeuva (Anacardiaceae) cause midgut damage when ingested by Nasutitermes corniger (Isoptera: Termitidae) workers.

    PubMed

    Lima, Thâmarah A; Fernandes, Kenner M; Oliveira, Ana Patrícia S; Dornelles, Leonardo P; Martins, Gustavo F; Napoleão, Thiago H; Paiva, Patrícia Mg

    2017-05-01

    Myracrodruon urundeuva is a hardwood tree, and its bark, heartwood and leaf contain lectins (MuBL, MuHL and MuLL respectively) with termiticidal activity against Nasutitermes corniger. In this work, the effects of these lectins on the midgut of N. corniger workers were evaluated. The insects were supplied with an artificial diet containing the lectins at their respective LC 50 (previously determined). At 48 h after treatment, the midguts were dissected and fixed for histopathology analyses. Toluidine-blue-stained midguts from lectin-treated workers showed disorganisation, with the presence of debris in the lumen and the absence of brush border. Fluorescence microscopy revealed that the numbers of digestive and proliferating cells were lower in lectin-treated individuals than in the control, and caspase-3 staining confirmed the occurrence of cell apoptosis. Enteroendocrine cells were not seen in the treated individuals. The midguts from treated insects showed greater staining for peroxidase than the control, suggesting that the lectins caused oxidative stress. Staining with wheat germ agglutinin conjugated to FITC revealed that the lectins interfered with the integrity of the peritrophic matrix. This study showed that termiticidal lectins from M. urundeuva cause severe injuries, oxidative stress and cell death in the midgut of N. corniger workers. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

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

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

    Matsuno, Keita; Nakayama, Eri; Noyori, Osamu

    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 ofmore » 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.« less

  18. Interaction of glycophorin A with lectins as measured by surface plasmon resonance (SPR).

    PubMed

    Krotkiewska, Bozena; Pasek, Marta; Krotkiewski, Hubert

    2002-01-01

    Glycophorin A (GPA), the major sialoglycoprotein of the human erythrocyte membrane, was isolated from erythrocytes of healthy individuals of blood groups A, B and O using phenol-water extraction of erythrocyte membranes. Interaction of individual GPA samples with three lectins (Psathyrella velutina lectin, PVL; Triticum vulgaris lectin, WGA and Sambucus nigra I agglutinin SNA-I) was analyzed using a BIAcore biosensor equipped with a surface plasmon resonance (SPR) detector. The experiments showed no substantial differences in the interaction between native and desialylated GPA samples originating from erythrocytes of either blood group and each of the lectins. Desialylated samples reacted weaker than the native ones with all three lectins. PVL reacted about 50-fold more strongly than WGA which, similar to PVL, recognizes GlcNAc and Neu5Ac residues. SNA-I lectin, recognizing alpha2-6 linked Neu5Ac residues, showed relatively weak reaction with native and only residual reaction with desialylated GPA samples. The data obtained show that SPR is a valuable method to determine interaction of glycoproteins with lectins, which potentially can be used to detect differences in the carbohydrate moiety of individual glycoprotein samples.

  19. Structure of a lectin with antitumoral properties in king bolete (Boletus edulis) mushrooms.

    PubMed

    Bovi, Michele; Carrizo, Maria E; Capaldi, Stefano; Perduca, Massimiliano; Chiarelli, Laurent R; Galliano, Monica; Monaco, Hugo L

    2011-08-01

    A novel lectin has been isolated from the fruiting bodies of the common edible mushroom Boletus edulis (king bolete, penny bun, porcino or cep) by affinity chromatography on a chitin column. We propose for the lectin the name BEL (B. edulis lectin). BEL inhibits selectively the proliferation of several malignant cell lines and binds the neoplastic cell-specific T-antigen disaccharide, Galβ1-3GalNAc. The lectin was structurally characterized: the molecule is a homotetramer and the 142-amino acid sequence of the chains was determined. The protein belongs to the saline-soluble family of mushroom fruiting body-specific lectins. BEL was also crystallized and its three-dimensional structure was determined by X-ray diffraction to 1.15 Å resolution. The structure is similar to that of Agaricus bisporus lectin. Using the appropriate co-crystals, the interactions of BEL with specific mono- and disaccharides were also studied by X-ray diffraction. The six structures of carbohydrate complexes reported here provide details of the interactions of the ligands with the lectin and shed light on the selectivity of the two distinct binding sites present in each protomer.

  20. Potential immunomodulatory effects of plant lectins in Schistosoma mansoni infection.

    PubMed

    Reis, Eliana A G; Athanazio, Daniel A; Cavada, Benildo Sousa; Teixeira, Edson Holanda; de Paulo Teixeira Pinto, Vicente; Carmo, Theomira M A; Reis, Alice; Trocolli, Graziela; Croda, Julio; Harn, Donald; Barral-Netto, Manoel; Reis, Mitermayer G

    2008-01-01

    Lectins are sugar-binding glycoproteins that can stimulate, in a non-antigen-specific fashion, lymphocytes, leading to proliferation and cytokine production. Some lectins are utilized as in vitro mitogenic lymphocyte stimulators and their use as immunomodulators against infectious diseases has been evaluated experimentally. In the experimental murine model, the immune response to schistosomiasis is Th1-like during the initial stage of infection, with a shift towards a Th2-like response after oviposition. We report the response of schistosomiasis patients' (n=37) peripheral blood mononuclear cells (PBMC) to stimulation by lectins, including newly isolated lectins from Brazilian flora, and by Schistosomamansoni soluble egg antigens (SEA). Cytokine production upon lectin stimulation ex vivo was assessed in PBMC supernatants, collected at 24 and 72 h, by sandwich ELISA to IL-5, IL-10, TNF-alpha and IFN-gamma. In PBMC from infected patients all but one of the lectins induced a Th2-like cytokine response, characterized by elevated IL-5 production that was higher than that induced by SEA stimulation alone. Our results show that the Th2 environment present during schistosomiasis is not affected and that it may be further stimulated by the presence of lectins.

  1. Structure, properties and enhanced expression of galactose-binding C-type lectins in mucous cells of gills from freshwater Japanese eels (Anguilla japonica).

    PubMed

    Mistry, A C; Honda, S; Hirose, S

    2001-11-15

    Using a Japanese-eel (Anguilla japonica) gill cDNA subtraction library, two novel beta-d-galactose-binding lectins were identified that belong to group VII of the animal C-type lectin family. The eel C-type lectins, termed eCL-1 and eCL-2, are simple lectins composed of 163 amino acid residues, including a 22-residue signal peptide for secretion and a single carbohydrate-recognition domain (CRD) of approximately 130 residues typical of C-type lectins. The galactose specificity of the CRD was suggested by the presence of a QPD motif and confirmed by a competitive binding assay. Using Ruthenium Red staining, the lectins were shown to bind Ca(2+) ions. SDS/PAGE showed that native eCL-1 and eCL-2 have an SDS-resistant octameric structure (a tetramer of disulphide-linked dimers). Northern and Western blot analyses demonstrated high-level expression of eCL-1 and eCL-2 mRNAs and their protein products in gills from freshwater eels, which decreased markedly when the eels were transferred from freshwater to seawater. Immunohistochemistry showed that the eel lectins are localized in the exocrine mucous cells of the gill.

  2. [Study on the extraction technology and hypoglycemic activity of lectin from Trichosanthes kirilowi].

    PubMed

    Li, Qiong; Ye, Xiao-Li; Zeng, Hong; Chen, Xin; Li, Xue-Gang

    2012-03-01

    To extract lectins from Trichosanthes kirilowi and study their hypoglycemic activity. The optimal extraction process included the following parameters were conformed by optimization analysis,lectins extracted from Trichosanthes kirilowi was achieved by ammonium sulfate precipitation; The agglutinate activity was determined by using the agglutination test with 5% human blood cells. Human hepatocarcinoma cell HepG2 and the alloxan-induced diabetic mice model were used to assess hypoglycemic activity of Lectin in Trichosanthes kirilowi. The agglutination indexes of lectins extraction buffer were 32; The cell and mice tests indicated that the lectins exhibited hypoglycemic activity in the 70% saturation. The optimum extraction technology is as follows: extraction with PBS, the material-water ratio is 1:30, the extraction time is 24 h, while the concentration of sodium chloride is 0 mol/L and pH is 7.2. Precipitate lectins by ammonium sulfate in the 70% saturation, centrifugal speed is 10 000 tracted from Trichosanthes kirilowi exposes proper hypoglycemic activity.

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

    PubMed

    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.

  4. High-Throughput Lectin Microarray-Based Analysis of Live Cell Surface Glycosylation

    PubMed Central

    Li, Yu; Tao, Sheng-ce; Zhu, Heng; Schneck, Jonathan P.

    2011-01-01

    Lectins, plant-derived glycan-binding proteins, have long been used to detect glycans on cell surfaces. However, the techniques used to characterize serum or cells have largely been limited to mass spectrometry, blots, flow cytometry, and immunohistochemistry. While these lectin-based approaches are well established and they can discriminate a limited number of sugar isomers by concurrently using a limited number of lectins, they are not amenable for adaptation to a high-throughput platform. Fortunately, given the commercial availability of lectins with a variety of glycan specificities, lectins can be printed on a glass substrate in a microarray format to profile accessible cell-surface glycans. This method is an inviting alternative for analysis of a broad range of glycans in a high-throughput fashion and has been demonstrated to be a feasible method of identifying binding-accessible cell surface glycosylation on living cells. The current unit presents a lectin-based microarray approach for analyzing cell surface glycosylation in a high-throughput fashion. PMID:21400689

  5. Lectins in human pathogenic fungi.

    PubMed

    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.

  6. Network analysis reveals the recognition mechanism for complex formation of mannose-binding lectins

    NASA Astrophysics Data System (ADS)

    Jian, Yiren; Zhao, Yunjie; Zeng, Chen

    The specific carbohydrate binding of lectin makes the protein a powerful molecular tool for various applications including cancer cell detection due to its glycoprotein profile on the cell surface. Most biologically active lectins are dimeric. To understand the structure-function relation of lectin complex, it is essential to elucidate the short- and long-range driving forces behind the dimer formation. Here we report our molecular dynamics simulations and associated dynamical network analysis on a particular lectin, i.e., the mannose-binding lectin from garlic. Our results, further supported by sequence coevolution analysis, shed light on how different parts of the complex communicate with each other. We propose a general framework for deciphering the recognition mechanism underlying protein-protein interactions that may have potential applications in signaling pathways.

  7. Antiviral Lectins: Selective Inhibitors of Viral Entry

    PubMed Central

    Mitchell, Carter A.; Ramessar, Koreen; O’Keefe, Barry R.

    2017-01-01

    Many natural lectins have been reported to have antiviral activity. As some of these have been put forward as potential development candidates for preventing or treating viral infections, we have set out in this review to survey the literature on antiviral lectins. The review groups lectins by structural class and class of source organism we also detail their carbohydrate specificity and their reported antiviral activities. The review concludes with a brief discussion of several of the pertinent hurdles that heterologous proteins must clear to be useful clinical candidates and cites examples where such studies have been reported for antiviral lectins. Though the clearest path currently being followed is the use of antiviral lectins as anti-HIV microbicides via topical mucosal administration, some investigators have also found systemic efficacy against acute infections following subcutaneous administration. PMID:28322922

  8. The two envelope membrane glycoproteins of Tomato spotted wilt virus show differences in lectin-binding properties and sensitivities to glycosidases.

    PubMed

    Naidu, Rayapati A; Ingle, Caroline J; Deom, Carl M; Sherwood, John L

    2004-02-05

    Tomato spotted wilt virus (TSWV, Genus: Tospovirus, Family: Bunyaviridae) is a major constraint to the production of several different crops of agronomic and horticultural importance worldwide. The amino acid sequence of the two envelope membrane glycoproteins, designated as G(N) (N-terminal) and G(C) (C-terminal), of TSWV contain several tripeptide sequences, Asn-Xaa-Ser/Thr, suggesting that the proteins are N-glycosylated. In this study, the lectin-binding properties of the viral glycoproteins and their sensitivities to glycosidases were examined to obtain information on the nature of potential oligosaccharide moieties present on G(N) and G(C). The viral proteins were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and probed by affinoblotting using a battery of biotinylated lectins with specificity to different oligosaccharide structures. G(C) showed strong binding with five mannose-binding lectins, four N-acetyllactosamine-binding lectins and one fucose-binding lectin. G(N) was resolved into two molecular masses and only the slow migrating form showed binding, albeit to a lesser extent than G(C), with three of the five mannose-binding lectins. The N-acetyllactosamine- and fucose-specific lectins did not bind to either molecular mass form of G(N). None of the galactose-, N-acetylgalactosamine-, or sialic acid-binding lectins tested showed binding specificity to G(C) or G(N). Treatment of the denatured virions with endoglycosidase H and peptide:N-glycosidase F (PNGase F) resulted in a significant decrease in the binding of G(C) to high mannose- and N-acetyllactosamine-specific lectins. However, no such differences in lectin binding were apparent with G(N). These results indicate the presence of N-linked oligosaccharides of high mannose- and complex-type on G(C) and possibly high mannose-type on G(N). Differences in the extent of binding of the two envelope glycoproteins to different lectins suggest that G(C) is likely to be more heavily N-glycosylated than G(N). No evidence was observed for the presence of O-linked oligosaccharides on G(N) or G(C).

  9. Enteral exposure to crude red kidney bean lectin induces maturation of the gut in suckling pigs.

    PubMed

    Rådberg, K; Biernat, M; Linderoth, A; Zabielski, R; Pierzynowski, S G; Weström, B R

    2001-10-01

    The present investigation characterized the effect of red kidney bean lectin exposure on gut maturation and function in young piglets. Eleven suckling pigs were given by stomach tube a crude red kidney bean lectin preparation (containing about 25% lectin, 400 mg/kg BW) (lectin-treated pigs) at 10, 11, and 12 d of life, and an additional 16 pigs (control pigs) were given saline instead. On the next day, the intestinal absorptive capacity was determined in vivo, and on the 14th d of life the piglets were killed and organs and small intestine samples were collected for analyses and in vitro permeability experiments. The lectin-treated pigs showed an increase in stomach weights and mucosa thickness, whereas no weight effect was found for the small intestine, spleen, liver, or adrenals. Morphometric analyses of the small intestine in lectin-treated pigs showed a decrease in villus heights, an increase in crypt depths and crypt cell mitotic indices, and fewer vacuolated enterocytes per villus and reduced vacuole size. Lectin treatment also resulted in a decrease in the absorption of different-sized marker molecules after gavage feeding, a decrease in intestinal marker permeability, and a change in small intestinal disaccharidase activities, with increased maltase and sucrase activities. The size of the pancreatic acini was also greater in the lectin-treated pigs, but no increases in enzyme content or pancreatic weight could be determined. In addition, the blood plasma levels of cholecystokinin were higher in the lectin-treated than in the control pigs. The results indicate that exposure to crude red kidney bean lectin induces structural and functional maturation of the gut and pancreatic growth in young suckling piglets. This possibility of inducing gut maturation may lead to an improvement in the piglets' ability to adapt to weaning and to an increase in the growth and health of these animals.

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

    PubMed

    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.

  11. The Lectin Pathway in Thrombotic Conditions-A Systematic Review.

    PubMed

    Larsen, Julie Brogaard; Hvas, Christine Lodberg; Hvas, Anne-Mette

    2018-06-04

    The lectin pathway of the complement system can activate the coagulation system in vitro, but the role of the lectin pathway in haemostatic activation and thrombosis in vivo is not clear. We performed a systematic review of the existing literature on associations between the lectin pathway and arterial and venous thrombosis, in accordance with the Assessing the Methodological Quality of Systematic Reviews guidelines. PubMed and Embase were searched from January 1990 to March 2017. We included original studies on human study populations investigating associations between the lectin pathway (protein serum levels, genotype or gene expression) and thrombotic conditions or laboratory coagulation markers. Exclusion criteria were case studies including fewer than five cases, conference abstracts or any other language than English. In total, 43 studies were included which investigated associations between the lectin pathway and cardiovascular thrombotic events (CVEs) ( n  = 22), ischaemic stroke ( n  = 9), CVE and stroke ( n  = 1) and other conditions (systemic lupus erythematosus [ n  = 6], sepsis-related coagulopathy [ n  = 3], pulmonary embolism [ n  = 1], asparaginase treatment [ n  = 1]). Studies on the lectin pathway and CVE risk reported discrepant results, as both high and low mannose-binding lectin (MBL) serum levels were found to correlate with increased CVE risk. In ischaemic stroke patients, occurrence of stroke as well as increased stroke severity and poor outcome were consistently associated with high serum MBL. For other thromboembolic conditions, only few studies were identified. In conclusion, lectin pathway activation may negatively influence outcome after ischaemic stroke and possibly contribute to CVE risk. Further research is warranted to elucidate the role of the lectin pathway in other thrombotic conditions. Schattauer GmbH Stuttgart.

  12. Agglutination of Helicobacter pylori coccoids by lectins

    PubMed Central

    Khin, Mar Mar; Hua, Jie Song; Ng, Han Cong; Wadström, Torkel; Ho, Bow

    2000-01-01

    AIM: To study the agglutination pattern of Helicobacter pylori coccoid and spiral forms. METHODS: Assays of agglutination and agglutination inhibition were applied using fifteen commercial lectins. RESULTS: Strong agglutination was observed with mannose-specific Concanavalin A (Con A), fucose-specific Tetragonolobus purpureas (Lotus A) and N-acetyl glucosamine-specific Triticum vulgaris (WGA) lectins. Mannose and fucose specific lectins were reactive with all strains of H. pylori coccoids as compared to the spirals. Specific carbohydrates, glycoproteins and mucin were shown to inhibit H. pylori lectin-agglutination reactions. Pre-treatment of the bacterial cells with formalin and sulphuric acid did not alter the agglutination patterns with lectins. However, sodium periodate treatment of bacterial cells were shown to inhibit agglutination reaction with Con A, Lotus A and WGA lectins. On the contrary, enzymatic treatment of coccoids and spirals did not show marked inhibition of H. pylori lectin agglutination. Interes tingly, heating of H. pylori cells at 60 °C for 1 h was shown to augment the agglutination with all of the lectins tested. CONCLUSION: The considerable differences in lectin agglutination patterns seen among the two differentiated forms of H. pylori might be attributable to the structural changes during the events of morphological transformation, resulting in exposing or masking some of the sugar residues on the cell surface. Possibility of various sugar residues on the cell wall of the coccoids may allow them to bind to different carbohydrate receptors on gastric mucus and epithelial cells. The coccoids with adherence characteristics like the spirals could aid in the pathogenic process of Helicobacter infection. This may probably lead to different clinical outcome of H. pylori associated gastroduodenal disease. PMID:11819557

  13. Vitronectin (Vn) glycosylation patterned by lectin affinity assays-A potent glycoproteomic tool to discriminate plasma Vn from cancer ascites Vn.

    PubMed

    Benachour, H; Leroy-Dudal, J; Agniel, R; Wilson, J; Briand, M; Carreiras, F; Gallet, O

    2018-05-01

    Changes in glycosylation have been associated with human cancer, but their complexity poses an analytical challenge. Ovarian cancer is a major cause of death in women because of an often late diagnosis. At least one-third of patients presents ascites fluid at diagnosis, and almost all have ascites at recurrence. Vitronectin (Vn) is a multifunctional glycoprotein that is suggested to be implicated in ovarian cancer metastasis and is found within ascites. The present study evaluated the potential of using lectin affinity for characterizing the glycosylation pattern of Vn. Human Vn was purified from 1 sample of ovarian cancer ascites or a pool of plasma samples. Consistent findings were observed with both dot blot and lectin array assays. Based on a panel of 40 lectins, the lectin array revealed discriminant patterns of lectin binding to Vn glycans. Interestingly, almost all the highlighted interactions were found to be higher with Vn from ascites relative to the plasma counterpart. Also, the lectin array was able to discriminate profiles of lectin interactions (ConA, SNA-I, PHA-E, PHA-L) between Vn samples that were not evident using dot blot, indicating its high sensitivity. The model of ConA binding during thermal unfolding of Vn confirmed the higher accessibility of mannosylated glycans in Vn from ascites as monitored by turbidimetry. Thus, this study demonstrated the usefulness of lectins and the lectin array as a glycoproteomic tool for high throughput and sensitive analysis of glycosylation patterns. Our data provide novel insights concerning Vn glycosylation patterns in clinical specimens, paving the way for further investigations regarding their functional impact and clinical interest. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Stimulation of IFN-γ production by garlic lectin in mouse spleen cells: involvement of IL-12 via activation of p38 MAPK and ERK in macrophages.

    PubMed

    Dong, Qing; Sugiura, Tsutomu; Toyohira, Yumiko; Yoshida, Yasuhiro; Yanagihara, Nobuyuki; Karasaki, Yuji

    2011-02-15

    Several lectins, present in beans and edible plant products, have immuno-potentiating and anti-tumor activities. We here report the effects of garlic lectin purified from garlic bulbs on the production of cytokines such as interleukin-12 (IL-12) and interferon-γ (IFN-γ) in the mouse. Garlic lectin induced IFN-γ production in spleen cells in a bell-shaped time (24-60 h)- and concentration (0.25-2.0 mg/ml)-dependent manner. The maximal enhancement was observed at 36 h with 0.5 mg/ml of garlic lectin. The stimulatory effect of garlic lectin on IFN-γ production was completely inhibited by both actinomycin D and cycloheximide, an inhibitor of ribosomal protein synthesis and DNA-dependent RNA polymerase, respectively, and was associated with an increase in IFN-γ mRNA level. Garlic lectin also induced IL-12 production in mouse peritoneal macrophages in a concentration (0.25-1.0 mg/ml)- and bell-shaped time (3-24 h)-dependent manner. The lectin increased the phosphorylation of extracellular signal-regulated kinases (ERK) and p38 mitogen-activated protein kinase (p38 MAPK) in macrophages. Furthermore, specific pharmacological inhibitors of ERK kinase (U0126) and p38 MAPK (SB203580) also suppressed the production of IL-12 induced by garlic lectin. The present findings suggest that garlic lectin induces IL-12 production via activation of p38 MAPK and ERK in mouse macrophages, which, in turn, stimulates IFN-γ production through an increase in IFN-γ mRNA in the spleen cells. Copyright © 2010 Elsevier GmbH. All rights reserved.

  15. Antibacterial activity of lactose-binding lectins from Bufo arenarum skin.

    PubMed

    Sánchez Riera, Alicia; Daud, Adriana; Gallo, Adriana; Genta, Susana; Aybar, Manuel; Sánchez, Sara

    2003-04-01

    Amphibians respond to microbial infection through cellular and humoral defense mechanisms such as antimicrobial protein secretion. Most humoral defense proteins are synthetized in the skin. In this study we isolated two beta-galactoside-binding lectins with molecular weights of 50 and 56 KDa from the skin of Bufo arenarum. These lectins have significant hemagglutination activity against trypsinized rabbit erythrocytes, which was inhibited by galactose-containing saccharides. They are water-soluble and independent of the presence of calcium. The antimicrobial analysis for each lectin was performed. At mumolar concentration lectins show strong bacteriostatic activity against Gram negative bacteria (Escherichia coli K12 4100 and wild strains of Escherichia coli and Proteus morganii) and Gram positive bacteria (Enterococcus faecalis). The antibacterial activity of these lectins may provide an effective defense against invading microbes in the amphibian Bufo arenarum.

  16. Developmental changes in the distribution of cecal lectin-binding sites of Balb-c mice.

    PubMed

    Doehrn, S; Breipohl, W; Lierse, W; Romaniuk, K; Young, W

    1992-01-01

    The existence of lectin-binding sites was investigated in the cecum of Balb-c mice at seven developmental stages ranging from 18 days post conception (p.c.) to 8 weeks after birth. Nine horseradish-peroxidase-conjugated lectins (concanavalin A, Triticum vulgaris, Dolichus biflorus, Helix pomatia, Arachis hypogaea, Glycine maximus, Lotus tetragonolobus, Ulex europaeus, Limulus polyphemus) were applied to 5- to 7-microns thin paraffin sections of Bouin-fixed tissue. After DAB staining the sections were evaluated by light microscopy. It was shown that each lectin exhibits a unique developmental pattern. The adult binding patterns were established at the age of 3-4 weeks with only minor changes occurring thereafter. Considerable differences in binding patterns occurred not only between lectins of different groups but also between lectins with the same nominal monosaccharide specificity.

  17. Studies on the interaction of the Sophora japonica lectin and concanavalin A with erythrocytes and lymphocytes.

    PubMed Central

    Poretz, R D; Barth, R F

    1976-01-01

    The agglutinating activity of lectins from the seeds of Sophora japonica and Canavalia ensiformis (concanavalin A) with human and murine erythrocytes and lymphocytes have been compared to one another and related to the mitogenic and immunosuppressive properties of these purified proteins. The S. japonica lectin, which demonstrates blood group specificity, is more active than concanavalin A with human erythrocytes, but has a much lower reactivity than concanavalin A with murine red blood cells. Ficin treatment of human erythrocytes results in an increase in agglutinability by both lectins as well as causing the appearance of S. japonica lectin receptors on type O cells. Treatment of murine reythrocytes with ficin alone or followed by beta-galactosidase causes the cells to be more reactive with concanavalin A. Beta-Galactosidase alone has no observable affect on the cells. In contrast, the agglutinability of cells by the S. japonica lectin increases after ficin treatment but is not affected by beta-galaetosidose treatment either after or in the absence of ficinization. Murine lymphocytes react with both lectins in a manner paralleling the agglutination patterns of murine erythrocytes. The S. japonica lectin appears to be devoid of mitogenic and immuno-suppressive activity, in contrast to concanavalin A which suppresses the T helper-dependent antibody response to sheep erythrocytes. These results are discussed in terms of the types of lectin receptors on lymphocytes related to agglutination, induction of blastogenesis and immuno-suppression. PMID:955676

  18. The identification of plant lectins with mucosal adjuvant activity.

    PubMed

    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.

  19. The identification of plant lectins with mucosal adjuvant activity

    PubMed Central

    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

  20. Integrative analysis workflow for the structural and functional classification of C-type lectins

    PubMed Central

    2011-01-01

    Background It is important to understand the roles of C-type lectins in the immune system due to their ubiquity and diverse range of functions in animal cells. It has been observed that currently confirmed C-type lectins share a highly conserved domain known as the C-type carbohydrate recognition domain (CRD). Using the sequence profile of the CRD, an increasing number of putative C-type lectins have been identified. Hence, it is highly needed to develop a systematic framework that enables us to elucidate their carbohydrate (glycan) recognition function, and discover their physiological and pathological roles. Results Presented herein is an integrated workflow for characterizing the sequence and structural features of novel C-type lectins. Our workflow utilizes web-based queries and available software suites to annotate features that can be found on the C-type lectin, given its amino acid sequence. At the same time, it incorporates modeling and analysis of glycans - a major class of ligands that interact with C-type lectins. Thereafter, the results are analyzed together with context-specific knowledge to filter off unlikely predictions. This allows researchers to design their subsequent experiments to confirm the functions of the C-type lectins in a systematic manner. Conclusions The efficacy and usefulness of our proposed immunoinformatics workflow was demonstrated by applying our integrated workflow to a novel C-type lectin -CLEC17A - and we report some of its possible functions that warrants further validation through wet-lab experiments. PMID:22372988

  1. Plant as a plenteous reserve of lectin

    PubMed Central

    Hivrale, AU; Ingale, AG

    2013-01-01

    Lectins are clusters of glycoproteins of nonimmune foundation that combine specifically and reversibly to carbohydrates, mainly the sugar moiety of glycoconjugates, resulting in cell agglutination and precipitation of glycoconjugates. They are universally distributed in nature, being established in plants, fungi, viruses, bacteria, crustacea, insects, and animals, but leguminacae plants are rich source of lectins. The present review reveals the structure, biological properties, and application of plant lectins. PMID:24084524

  2. Lectin cDNA and transgenic plants derived therefrom

    DOEpatents

    Raikhel, N.V.

    1994-01-04

    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. GOVERNMENT RIGHTS This application was funded under Department of Energy Contract DE-AC02-76ER01338. The U.S. Government has certain rights under this application and any patent issuing thereon. .

  3. Lectin cDNA and transgenic plants derived therefrom

    DOEpatents

    Raikhel, Natasha V.

    1994-01-04

    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. GOVERNMENT RIGHTS This application was funded under Department of Energy Contract DE-AC02-76ER01338. The U.S. Government has certain rights under this application and any patent issuing thereon.

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

    PubMed Central

    Van Holle, Sofie; De Schutter, Kristof; Eggermont, Lore; Tsaneva, Mariya; Dang, Liuyi; Van Damme, Els J. M.

    2017-01-01

    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. PMID:28587095

  5. Lectins for gastrointestinal targeting--15 years on.

    PubMed

    Woodley, J F

    2000-01-01

    In the mid-1980s, the concept of bioadhesion using synthetic polymers emerged, and brought with it the promise of improved efficiency for the delivery of drugs via mucosal surfaces. Studies in the author's laboratory concentrated on 'biological' bioadhesion using the naturally-occurring proteins, lectins, which recognise and bind sugars in glycoconjugates, such as those found on the surfaces of cells. Tomato Lectin (TL) was extensively studied as a putative non-toxic lectin with potential for drug targeting/delivery to the gastrointestinal (GI) tract. In vitro, the TL displayed impressive binding to the intestinal mucosa, but in vivo failed to significantly modify intestinal transit. A number of research groups have coupled the TL to microparticles, and significant systemic uptake of these has been observed in animal studies. Polymers with pendant sugars have also been shown to be bioadhesive, by interacting with endogenous lectins present on the cells of the GI tract. The use of lectins to target to Peyer's patches and diseased tissues in the colon is an interesting development, but much work remains to be done. Lectins also have potential in mucosal vaccines. Before advanced drug delivery systems using lectins can be realised, rigorous evaluation of their toxicity and immunogenicity will be required, but they clearly offer a number of possibilities for GI drug targeting systems in the future.

  6. BEL β-trefoil: a novel lectin with antineoplastic properties in king bolete (Boletus edulis) mushrooms.

    PubMed

    Bovi, Michele; Cenci, Lucia; Perduca, Massimiliano; Capaldi, Stefano; Carrizo, Maria E; Civiero, Laura; Chiarelli, Laurent R; Galliano, Monica; Monaco, Hugo L

    2013-05-01

    A novel lectin was purified from the fruiting bodies of king bolete mushrooms (Boletus edulis, also called porcino, cep or penny bun). The lectin was structurally characterized i.e its amino acid sequence and three-dimensional structure were determined. The new protein is a homodimer and each protomer folds as β-trefoil domain and therefore we propose the name Boletus edulis lectin (BEL) β-trefoil to distinguish it from the other lectin that has been described in these mushrooms. The lectin has potent anti-proliferative effects on human cancer cells, which confers to it an interesting therapeutic potential as an antineoplastic agent. Several crystal forms of the apoprotein and of complexes with different carbohydrates were studied by X-ray diffraction. The structure of the apoprotein was solved at 1.12 Å resolution. The interaction of the lectin with lactose, galactose, N-acetylgalactosamine and T-antigen disaccharide, Galβ1-3GalNAc, was examined in detail. All the three potential binding sites present in the β-trefoil fold are occupied in at least one crystal form and are described in detail in this paper. No important conformational changes are observed in the lectin when comparing its co-crystals with carbohydrates with those of the ligand-free protein.

  7. Purification and characterization of a glucosamine-binding antifungal lectin from Phaseolus vulgaris cv. Chinese pinto beans with antiproliferative activity towards nasopharyngeal carcinoma cells.

    PubMed

    Ang, Andrew Si Wo; Cheung, Randy Chi Fai; Dan, Xiuli; Chan, Yau Sang; Pan, Wenliang; Ng, Tzi Bun

    2014-01-01

    A lectin has successfully been isolated from Phaseolus vulgaris cv. Chinese pinto bean using affinity chromatography, ion exchange chromatography, and gel filtration in succession, with a 15.4-fold purification. Investigation of its characteristics revealed that Chinese pinto bean lectin (CPBL) was a 58-kDa dimeric glucosamine-binding protein. Its Mg(2+)-dependent hemagglutinating activity was stable at pH 7-8 and at or below 60 °C. When the purified lectin was tested against six fungal species including Phyllosticta citriasiana, Magnaporthe grisea, Bipolans maydis, Valsa mali, Mycosphaerella arachidicola, and Setosphaeria turcica, only the mycelial growth of V. mali was reduced by 30.6 % by the lectin at 30 μM. The lectin did not exert any discernible antiproliferative effects on breast cancer MCF-7 cells, but was able to suppress proliferation of nasopharyngeal carcinoma HONE-1 cells, with an IC50 of 17.3 μM, as revealed by the MTT assay. Since few plant lectins demonstrate antifungal activity against V. mali, and not many others have inhibitory effects on HONE-1 cells, CPBL is a distinctive lectin which may be exploited for development into an agent against V. mali and HONE-1 cells.

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

    PubMed

    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.

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

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

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

    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 bothmore » 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.« less

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

    PubMed

    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.

  11. Structure, properties and enhanced expression of galactose-binding C-type lectins in mucous cells of gills from freshwater Japanese eels (Anguilla japonica).

    PubMed Central

    Mistry, A C; Honda, S; Hirose, S

    2001-01-01

    Using a Japanese-eel (Anguilla japonica) gill cDNA subtraction library, two novel beta-d-galactose-binding lectins were identified that belong to group VII of the animal C-type lectin family. The eel C-type lectins, termed eCL-1 and eCL-2, are simple lectins composed of 163 amino acid residues, including a 22-residue signal peptide for secretion and a single carbohydrate-recognition domain (CRD) of approximately 130 residues typical of C-type lectins. The galactose specificity of the CRD was suggested by the presence of a QPD motif and confirmed by a competitive binding assay. Using Ruthenium Red staining, the lectins were shown to bind Ca(2+) ions. SDS/PAGE showed that native eCL-1 and eCL-2 have an SDS-resistant octameric structure (a tetramer of disulphide-linked dimers). Northern and Western blot analyses demonstrated high-level expression of eCL-1 and eCL-2 mRNAs and their protein products in gills from freshwater eels, which decreased markedly when the eels were transferred from freshwater to seawater. Immunohistochemistry showed that the eel lectins are localized in the exocrine mucous cells of the gill. PMID:11695997

  12. Affinity entrapment of oligosaccharides and glycopeptides using free lectin solution.

    PubMed

    Yodoshi, Masahiro; Oyama, Takehiro; Masaki, Ken; Kakehi, Kazuaki; Hayakawa, Takao; Suzuki, Shigeo

    2011-01-01

    Two procedures were proposed for the specific recovery of fluorescent derivatives of glycoprotein-derived oligosaccharides and tryptic glycopeptides using certain plant lectins. The first was based on the salting out of oligosaccharide-lectin conjugates with ammonium sulfate. Oligosaccharides specifically bound to lectins were recovered free from lectins using ethanol precipitation after dissolution in water. This method enabled group separation of 2-aminopyridine-labeled oligosaccharides derived from ovalbumin to galacto-oligosaccharides and agalacto-oligosaccharides by Ricinus communis agglutinin, and to high mannose- and hybrid-type oligosaccharides by wheat-germ agglutinin. Fractional precipitation based on differences in affinity for concanavalin A was accomplished by adding an appropriate concentration of methyl α-mannoside as an inhibitor. In the second method, tryptic digests of glycoproteins were mixed with a lectin solution, and the glycopeptide-lectin conjugates were specifically trapped on a centrifugal ultrafiltration membrane with cut-off of 10 kD. Trapped glycopeptides, as retentates, were passed through membranes by resuspension in diluted acid. This method is particularly useful for the enrichment of glycopeptides in protease digestion mixtures for glycosylation analyses by liquid chromatography-mass spectrometry.

  13. Isolation and characterization of lectin from Thai marine crab (Scylla serrata) with binding specificity to sialoglycoconjugates and its application.

    PubMed

    Kongtawelert, P

    1998-12-01

    A lectin from Thai marine carb (Scylla serrata) hemolymph has been isolated and purified by affinity column chromatography and preparative electrophoresis. The amino acid composition and 10 amino-terminal residues have been deduced, and its reactivities have been studied using a biotin labeling technique. A method for the determination of sialoglycoconjugates in human serum is described using this lectin. The principle is based on the reaction between the sialoglycoconjugates and biotinylated lectin. The bovine submaxillary mucin (BSM) is immobilized on polystyrene microplate. The unknown sample or sialoglycoconjugate (BSM equivalent) standards, together with excess biotinylated purified lectin (B-lectin), are then added. The B-lectin that binds to the immobilized BSM is then incubated with the peroxidase-conjugated monoclonal antibiotin antibody, and the color that develops after the addition of enzyme substrate is determined by light absorption using a microplate reader. The assay is not only convenient and reliable, but also capable of measuring sialoglycoconjugates in solution at the submicrogram level. It was used in determining the sialoglycoconjugates in human serum from normal subjects and samples positive for carcinoembryonic antigen.

  14. Diversity in recognition of glycans by F-type lectins and galectins: molecular, structural, and biophysical aspects

    PubMed Central

    Vasta, Gerardo R.; Ahmed, Hafiz; Bianchet, Mario A.; Fernández-Robledo, José A.; Amzel, L. Mario

    2013-01-01

    Although lectins are “hard-wired” in the germline, the presence of tandemly arrayed carbohydrate recognition domains (CRDs), of chimeric structures displaying distinct CRDs, of polymorphic genes resulting in multiple isoforms, and in some cases, of a considerable recognition plasticity of their carbohydrate binding sites, significantly expand the lectin ligand-recognition spectrum and lectin functional diversification. Analysis of structural/functional aspects of galectins and F-lectins—the most recently identified lectin family characterized by a unique CRD sequence motif (a distinctive structural fold) and nominal specificity for l-Fuc—has led to a greater understanding of self/nonself recognition by proteins with tandemly arrayed CRDs. For lectins with a single CRD, however, recognition of self and nonself glycans can only be rationalized in terms of protein oligomerization and ligand clustering and presentation. Spatial and temporal changes in lectin expression, secretion, and local concentrations in extracellular microenvironments, as well as structural diversity and spatial display of their carbohydrate ligands on the host or microbial cell surface, are suggestive of a dynamic interplay of their recognition and effector functions in development and immunity. PMID:22973821

  15. Lectin of Bacillus subtilis sp. as overinducer of gamma-interferonogenesis.

    PubMed

    Kishko, Ia H; Vasylenko, M I; Pidhors'kyĭ, V S; Kovalenko, E O

    1997-01-01

    It has been demonstrated experimentally that lectin of Bacillus subtilis sp. in comparison with generally accepted Con A, PHA and lectin of "gold rain" grass--Laburnum anagyroides M e d i k in trials on white mice of CBA line gave in 4 hours of induction maximal titers of gamma-IFN in blood serum of animals--153.6 +/- 17.0 IU/ml. Practically identical titers had been obtained after induction by lectin "gold rain", some lower--after Con A and PHA. At swine gamma-IFN synthesis optimal density of cell suspension must contain 2.5 + 10(7) immunocytes in 1 ml, owing to which it is possible to obtain the titer equal 1 : 2150. Materials with using of bacterial lectins at various degree of purification had shown that maximal titers in blood serum of mongrel white mice were registered at administration to animals of non-purified lectin, 4 times lower--at using of half-purified and purified lectins. Data of these trials in vivo were confirmed by materials of gamma-IFN induction by immunocytes of swine, cattle and even man.

  16. Lectin-functionalized poly(glycidyl methacrylate)-block-poly(vinyldimethyl azlactone) surface supports for high avidity microbial capture

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

    Hansen, Ryan R; Hinestrosa Salazar, Juan P; Shubert, Katherine R

    2013-01-01

    Microbial exopolysaccharides (EPS) play a critical and dynamic role in shaping the interactions between microbial community members and their local environment. The capture of targeted microbes using surface immobilized lectins that recognize specific extracellular oligosaccharide moieties offers a non-destructive method for functional characterization based on EPS content. In this report, we evaluate the use of the block co-polymer, poly(glycidyl methacrylate)-block-4,4-dimethyl-2-vinylazlactone (PGMA-b-PVDMA), as a surface support for lectin-specific microbial capture. Arrays of circular polymer supports ten micron in diameter were generated on silicon substrates to provide discrete, covalent coupling sites for Triticum vulgare and Lens culinaris lectins. These supports promoted microbemore » adhesion and colony formation in a lectin-specific manner. Silicon posts with similar topography containing only physisorbed lectins showed significantly less activity. These results demonstrate that micropatterned PGMA-b-PVDMA supports provide a unique platform for microbial capture and screening based on EPS content by combining high avidity lectin surfaces with three-dimensional topography.« less

  17. A putative carbohydrate-binding domain of the lactose-binding Cytisus sessilifolius anti-H(O) lectin has a similar amino acid sequence to that of the L-fucose-binding Ulex europaeus anti-H(O) lectin.

    PubMed

    Konami, Y; Yamamoto, K; Osawa, T; Irimura, T

    1995-04-01

    The complete amino acid sequence of a lactose-binding Cytisus sessilifolius anti-H(O) lectin II (CSA-II) was determined using a protein sequencer. After digestion of CSA-II with endoproteinase Lys-C or Asp-N, the resulting peptides were purified by reversed-phase high performance liquid chromatography (HPLC) and then subjected to sequence analysis. Comparison of the complete amino acid sequence of CSA-II with the sequences of other leguminous seed lectins revealed regions of extensive homology. The amino acid sequence of a putative carbohydrate-binding domain of CSA-II was found to be similar to those of several anti-H(O) leguminous lectins, especially to that of the L-fucose-binding Ulex europaeus lectin I (UEA-I).

  18. Insecticidal activity of plant lectins and potential application in crop protection.

    PubMed

    Macedo, Maria Lígia R; Oliveira, Caio F R; Oliveira, Carolina T

    2015-01-27

    Lectins constitute a complex group of proteins found in different organisms. These proteins constitute an important field for research, as their structural diversity and affinity for several carbohydrates makes them suitable for numerous biological applications. This review addresses the classification and insecticidal activities of plant lectins, providing an overview of the applicability of these proteins in crop protection. The likely target sites in insect tissues, the mode of action of these proteins, as well as the use of lectins as biotechnological tools for pest control are also described. The use of initial bioassays employing artificial diets has led to the most recent advances in this field, such as plant breeding and the construction of fusion proteins, using lectins for targeting the delivery of toxins and to potentiate expected insecticide effects. Based on the data presented, we emphasize the contribution that plant lectins may make as tools for the development of integrated insect pest control strategies.

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

    NASA Astrophysics Data System (ADS)

    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.

  20. Quantitation and histochemical localization of galectin-1 and galectin-1-reactive glycoconjugates in fetal development of bovine organs.

    PubMed

    Kaltner, H; Lips, K S; Reuter, G; Lippert, S; Sinowatz, F; Gabius, H J

    1997-10-01

    The display of cellular oligosaccharide chains is known to undergo marked developmental changes, as monitored histochemically with plant lectins. In conjunction with endogenous lectins respective ligand structures may have a functional role during fetal development. The assumption of a recognitive, functionally productive interplay prompts the study of the expression of a tissue lectin and of lectin-reactive glycoconjugates concomitantly. Focusing on common beta-galactosides as constituents of oligosaccharide chains and the predominant member of the family of galectins in mammals, namely galectin-1, the question therefore is addressed as to whether expression of lectin and lectin-reactive glycoconjugates exhibits alterations, assessed in three morphologically defined fetal stages and in adult bovine organs. Using a sandwich ELISA, the level of the rather ubiquitous galectin-1 is mostly increased in adult organs relative to respective fetal stages, except for the case of kidney. This developmental course is seen rather seldom, when the amounts of lectin-reactive glycoproteins or glycolipids are quantitated in solid-phase assays after tissue homogenization. Western blotting, combined with probing by labeled galectin-1, discloses primarily quantitative changes in the reactivity of individual glycoproteins. Performing the same assays on extract aliquots with a plant agglutinin, namely the galactoside-binding mistletoe lectin, whose fine specificity is different from galectin-1, its reduced extent of binding in solid-phase assays and the disparate profile of lectin-reactive glycoproteins reveal a non-uniform developmental alteration within the group of structural variants of beta-galactosides. Although sample preparation can affect ligand preservation and/or presentation and thus restricts the comparability of biochemical and histochemical results, especially for soluble reactants, the histochemical studies on frozen and paraffin-embedded sections of bovine heart, kidney and liver demonstrate that the localization of the galectin and of lectin-reactive epitopes can show a similar distribution, as seen in liver and heart, with organ-typical quantitative changes of a rather similar staining profile (heart, kidney) or notable changes in the spatial distribution (liver) in the course of development. This report emphasizes the potential value of combined monitoring of the lectin and its potential in vivo ligands to contribute to eventually unravel organ-related function(s) of a tissue lectin.

  1. Interaction of a lectin from Psathyrella velutina mushroom with N-acetylneuraminic acid.

    PubMed

    Ueda, H; Kojima, K; Saitoh, T; Ogawa, H

    1999-04-01

    A lectin from the fruiting body of Psathyrella velutina has been used as a specific probe for non-reducing terminal N-acetylglucosamine residues. We reveal in this report that P. velutina lectin recognizes a non-reducing terminal N-acetylneuraminic acid residue in glycoproteins and oligosaccharides. Binding of biotinyl P. velutina lectin to N-acetylneuraminic acid residues was prevented by desialylation of glycoconjugates and was distinguished from the binding to N-acetylglucosamine. Sialooligosaccharides were retarded or bound and eluted with N-acetylglucosamine on a P. velutina lectin column, being differentiated from each other and also from the oligosaccharides with non-reducing terminal N-acetylglucosamine which bound more strongly to the column.

  2. Legume Lectins: Proteins with Diverse Applications

    PubMed Central

    Lagarda-Diaz, Irlanda; Guzman-Partida, Ana Maria; Vazquez-Moreno, Luz

    2017-01-01

    Lectins are a diverse class of proteins distributed extensively in nature. Among these proteins; legume lectins display a variety of interesting features including antimicrobial; insecticidal and antitumor activities. Because lectins recognize and bind to specific glycoconjugates present on the surface of cells and intracellular structures; they can serve as potential target molecules for developing practical applications in the fields of food; agriculture; health and pharmaceutical research. This review presents the current knowledge of the main structural characteristics of legume lectins and the relationship of structure to the exhibited specificities; provides an overview of their particular antimicrobial; insecticidal and antitumor biological activities and describes possible applications based on the pattern of recognized glyco-targets. PMID:28604616

  3. A single-molecule force spectroscopy study of the interactions between lectins and carbohydrates on cancer and normal cells

    NASA Astrophysics Data System (ADS)

    Zhao, Weidong; Cai, Mingjun; Xu, Haijiao; Jiang, Junguang; Wang, Hongda

    2013-03-01

    The interaction forces between carbohydrates and lectins were investigated by single-molecule force spectroscopy on both cancer and normal cells. The binding kinetics was also studied, which shows that the carbohydrate-lectin complex on cancer cells is less stable than that on normal cells.The interaction forces between carbohydrates and lectins were investigated by single-molecule force spectroscopy on both cancer and normal cells. The binding kinetics was also studied, which shows that the carbohydrate-lectin complex on cancer cells is less stable than that on normal cells. Electronic supplementary information (ESI) available: Experimental details. See DOI: 10.1039/c3nr00553d

  4. Plant Lectins Targeting O-Glycans at the Cell Surface as Tools for Cancer Diagnosis, Prognosis and Therapy.

    PubMed

    Poiroux, Guillaume; Barre, Annick; van Damme, Els J M; Benoist, Hervé; Rougé, Pierre

    2017-06-09

    Aberrant O -glycans expressed at the surface of cancer cells consist of membrane-tethered glycoproteins (T and Tn antigens) and glycolipids (Lewis a, Lewis x and Forssman antigens). All of these O -glycans have been identified as glyco-markers of interest for the diagnosis and the prognosis of cancer diseases. These epitopes are specifically detected using T/Tn-specific lectins isolated from various plants such as jacalin from Artocarpus integrifola , and fungi such as the Agaricus bisporus lectin. These lectins accommodate T/Tn antigens at the monosaccharide-binding site; residues located in the surrounding extended binding-site of the lectins often participate in the binding of more extended epitopes. Depending on the shape and size of the extended carbohydrate-binding site, their fine sugar-binding specificity towards complex O -glycans readily differs from one lectin to another, resulting in a great diversity in their sugar-recognition capacity. T/Tn-specific lectins have been extensively used for the histochemical detection of cancer cells in biopsies and for the follow up of the cancer progression and evolution. T/Tn-specific lectins also induce a caspase-dependent apoptosis in cancer cells, often associated with a more or less severe inhibition of proliferation. Moreover, they provide another potential source of molecules adapted to the building of photosensitizer-conjugates allowing a specific targeting to cancer cells, for the photodynamic treatment of tumors.

  5. Plant Lectins Targeting O-Glycans at the Cell Surface as Tools for Cancer Diagnosis, Prognosis and Therapy

    PubMed Central

    Poiroux, Guillaume; Barre, Annick; van Damme, Els J. M.; Benoist, Hervé; Rougé, Pierre

    2017-01-01

    Aberrant O-glycans expressed at the surface of cancer cells consist of membrane-tethered glycoproteins (T and Tn antigens) and glycolipids (Lewis a, Lewis x and Forssman antigens). All of these O-glycans have been identified as glyco-markers of interest for the diagnosis and the prognosis of cancer diseases. These epitopes are specifically detected using T/Tn-specific lectins isolated from various plants such as jacalin from Artocarpus integrifola, and fungi such as the Agaricus bisporus lectin. These lectins accommodate T/Tn antigens at the monosaccharide-binding site; residues located in the surrounding extended binding-site of the lectins often participate in the binding of more extended epitopes. Depending on the shape and size of the extended carbohydrate-binding site, their fine sugar-binding specificity towards complex O-glycans readily differs from one lectin to another, resulting in a great diversity in their sugar-recognition capacity. T/Tn-specific lectins have been extensively used for the histochemical detection of cancer cells in biopsies and for the follow up of the cancer progression and evolution. T/Tn-specific lectins also induce a caspase-dependent apoptosis in cancer cells, often associated with a more or less severe inhibition of proliferation. Moreover, they provide another potential source of molecules adapted to the building of photosensitizer-conjugates allowing a specific targeting to cancer cells, for the photodynamic treatment of tumors. PMID:28598369

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

    PubMed

    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.

  7. Purification and Characterization of a Lectin from Green Split Peas (Pisum sativum).

    PubMed

    Ng, Tzi Bun; Chan, Yau Sang; Ng, Charlene Cheuk Wing; Wong, Jack Ho

    2015-11-01

    Lectins have captured the attention of a large number of researchers on account of their various exploitable activities, including antitumor, immunomodulatory, antifungal, as well as HIV reverse transcriptase inhibitory activities. A mannose/glucose-specific lectin was isolated from green split peas (a variety of Pisum sativum) and characterized. The purification step involved anion-exchange chromatography on a DEAE-cellulose column, cation-exchange chromatography on an SP-Sepharose column, and gel filtration by fast protein liquid chromatography (FPLC) on Superdex 200. The purified lectin had a native molecular mass of around 50 kDa as determined by size exclusion chromatography. It appeared as a heterotetramer, composed of two distinct polypeptide bands with a molecular mass of 6 and 19 kDa, respectively, in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The N-terminal sequence of green split pea lectin shows some degree of homology compared to lectins from other legume species. Its hemagglutinating activity was inhibited by glucose, mannose, and sucrose, and attenuated at pH values higher than 12 or lower than 3. Hemagglutinating activity was preserved at temperatures lower than 80 °C. The lectin did not show antifungal activity toward fungi including Fusarium oxysporum, Botrytis cinerea, and Mycosphaerella arachidicola. Green split pea lectin showed a mitogenic effect toward murine splenocytes and could inhibit the activity of HIV-1 reverse transcriptase.

  8. Purification and biochemical characterization of a D-galactose binding lectin from Japanese sea hare (Aplysia kurodai) eggs.

    PubMed

    Kawsar, S M A; Matsumoto, R; Fujii, Y; Yasumitsu, H; Dogasaki, C; Hosono, M; Nitta, K; Hamako, J; Matsui, T; Kojima, N; Ozeki, Y

    2009-07-01

    A lectin was purified from Japanese sea hare Aplysia kurodai by lactosyl-agarose affinity chromatography. The molecular mass of the lectin was determined to be 56 and 32 kDa by SDS-PAGE under non-reducing and reducing conditions, respectively. It was found to agglutinate trypsinized and glutaraldehyde-fixed rabbit and human erythrocytes in the absence of divalent cations. The lectin exhibited stable thermo-tolerance as it retained hemagglutinating activity for 1 h even at 80 degrees C and showed stability at pH 10. By contrast, it was very sensitive at pH less than 5 and in the presence of the sulfhydryl-group preserving reagent, beta-mercaptoethanol. The hemagglutinating activity by the lectin was specifically inhibited by D-galactose, galacturonic acid, methyl-alpha- and methyl-beta-D-galactopyranoside, lactose, melibiose, and asialofetuin. The association rate constant (k(ass)) and dissociation rate constant (k(diss)) were determined for the lectin to be 4.3 x 10(5) M(-1) x sec(-1) and 2.2 x 10(-3) sec(-1), respectively, using a surface plasmon resonance biosensor. The lectin moderately inhibited cell proliferation in the P388 cell line dose dependently. Interestingly, lectin-treated cells did not show a fragmented DNA ladder as is caused by apoptosis, suggesting that the cell proliferation inhibition was caused by another unknown mechanism.

  9. Structural analysis, molecular docking and molecular dynamics of an edematogenic lectin from Centrolobium microchaete seeds.

    PubMed

    Neco, Antonio Hadson Bastos; Pinto-Junior, Vanir Reis; Araripe, David Alencar; Santiago, Mayara Queiroz; Osterne, Vinicius Jose Silva; Lossio, Claudia Figueiredo; Nobre, Clareane Avelino Simplicio; Oliveira, Messias Vital; Silva, Mayara Torquato Lima; Martins, Maria Gleiciane Queiroz; Cajazeiras, Joao Batista; Marques, Gabriela Fernandes Oliveira; Costa, Diego Rabelo; Nascimento, Kyria Santiago; Assreuy, Ana Maria Sampaio; Cavada, Benildo Sousa

    2018-05-24

    Lectins represent a class of proteins or glycoproteins capable of reversibly binding to carbohydrates. Seed lectins from the Dalbergieae tribe (Leguminosae) have structural variability, carbohydrate specificity, and biological effects, such as inflammation, vasorelaxation and cancer antigen binding. To comprehensively address these factors, the present work aimed to establish and characterize the three-dimensional structure of Centrolobium microchaete lectin (CML) by homology modeling, investigate protein-carbohydrate interactions and evaluate its inflammatory effect on mice. Molecular docking was performed to analyze interactions of the lectin with monosaccharides, disaccharides and N-glycans. Two dimannosides, methyl mannose-1,3-α-D-mannose (MDM) and mannose-1,3-α-D-mannose (M13), were used in molecular dynamics (MD) simulations to study the behavior of the carbohydrate-recognition domain (CRD) over time. Results showed an expanded domain within which hydrophobic interactions with the methyl group in the MDM molecule were established, thus revealing novel interactions for mannose-specific Dalbergieae lectins. To examine its biological activities, CML was purified in a single step by affinity chromatography on Sepharose-mannose matrix. The lectin demonstrated inflammatory response in the paw edema model and stimulated leukocyte migration to the animal peritoneal cavities, an effect elicited by CRD. For the first time, this work reports the molecular dynamics of a lectin from the Dalbergieae tribe. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. 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*

    PubMed Central

    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

  11. Microglial Lectins in Health and Neurological Diseases

    PubMed Central

    Siew, Jian Jing; Chern, Yijuang

    2018-01-01

    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 defense machinery. Most importantly, multiple studies have reported dysregulation of lectins in neurological disorders. Here, we reviewed recent studies on microglial lectins and their functions in CNS health and disease, and suggest that these lectin families are novel, potent therapeutic targets for neurological diseases. PMID:29867350

  12. Calcium-independent haemolysis via the lectin pathway of complement activation in the guinea-pig and other *

    PubMed Central

    Zhang, Y; Suankratay, C; Zhang, X-H; Jones, D R; Lint, T F; Gewurz, H

    1999-01-01

    We previously reported that complement-dependent haemolysis of sheep erythrocytes (E) coated with mannan (M) and sensitized with human mannan-binding lectin (MBL) via the lectin pathway in man occurs in Mg-EGTA and requires alternative pathway amplification. Calcium was required for MBL binding to E-M, but once the E-M-MBL intermediate was formed, MBL was retained and haemolysis occurred in the absence of calcium. Comparable or greater lectin pathway haemolysis in the absence of calcium was observed upon incubation of E-M-MBL in guinea-pig, rat, dog and pig sera, and was further investigated in the guinea-pig, in which titres were much higher (∼14-fold) than in man, and in contrast to humans, greater than classical pathway haemolytic activity. As in human serum, no lysis was observed in C4- or C2-deficient guinea-pig serum until purified C4 or C2, respectively, were restored. However, lectin pathway haemolytic activity in the guinea-pig did not require the alternative pathway. Removal (>98%) of factor D activity by three sequential passages through Sephadex G-75, resulting in serum which retained a normal classical pathway but no alternative pathway haemolytic activity, did not reduce the ability of guinea-pig serum to mediate haemolysis via the lectin pathway. Further, the C3-convertase formed via the lectin pathway (E-M-MBL-C4,2) lysed in C2-deficient guinea-pig but not human serum chelated with EDTA, a condition which precludes alternative pathway amplification. Thus, lectin pathway haemolysis occurs efficiently in guinea-pig serum, in the absence of calcium and without requirement for alternative pathway amplification. The guinea-pig provides a model for studying the assembly and haemolytic function of a lectin pathway which contrasts with the lectin pathway of man, and allows for comparisons that may help clarify the role of this pathway in complement biology. PMID:10457224

  13. High Throughput ELISAs to Measure a Unique Glycan on Transferrin in Cerebrospinal Fluid: A Possible Extension toward Alzheimer's Disease Biomarker Development

    PubMed Central

    Shirotani, Keiro; Futakawa, Satoshi; Nara, Kiyomitsu; Hoshi, Kyoka; Saito, Toshie; Tohyama, Yuriko; Kitazume, Shinobu; Yuasa, Tatsuhiko; Miyajima, Masakazu; Arai, Hajime; Kuno, Atsushi; Narimatsu, Hisashi; Hashimoto, Yasuhiro

    2011-01-01

    We have established high-throughput lectin-antibody ELISAs to measure different glycans on transferrin (Tf) in cerebrospinal fluid (CSF) using lectins and an anti-transferrin antibody (TfAb). Lectin blot and precipitation analysis of CSF revealed that PVL (Psathyrella velutina lectin) bound an unique N-acetylglucosamine-terminated N-glycans on “CSF-type” Tf whereas SSA (Sambucus sieboldiana agglutinin) bound α2,6-N-acetylneuraminic acid-terminated N-glycans on “serum-type” Tf. PVL-TfAb ELISA of 0.5 μL CSF samples detected “CSF-type” Tf but not “serum-type” Tf whereas SSA-TfAb ELISA detected “serum-type” Tf but not “CSF-type” Tf, demonstrating the specificity of the lectin-TfAb ELISAs. In idiopathic normal pressure hydrocephalus (iNPH), a senile dementia associated with ventriculomegaly, amounts of the SSA-reactive Tf were significantly higher than in non-iNPH patients, indicating that Tf glycan analysis by the high-throughput lectin-TfAb ELISAs could become practical diagnostic tools for iNPH. The lectin-antibody ELISAs of CSF proteins might be useful for diagnosis of the other neurological diseases. PMID:21876827

  14. High Throughput ELISAs to Measure a Unique Glycan on Transferrin in Cerebrospinal Fluid: A Possible Extension toward Alzheimer's Disease Biomarker Development.

    PubMed

    Shirotani, Keiro; Futakawa, Satoshi; Nara, Kiyomitsu; Hoshi, Kyoka; Saito, Toshie; Tohyama, Yuriko; Kitazume, Shinobu; Yuasa, Tatsuhiko; Miyajima, Masakazu; Arai, Hajime; Kuno, Atsushi; Narimatsu, Hisashi; Hashimoto, Yasuhiro

    2011-01-01

    We have established high-throughput lectin-antibody ELISAs to measure different glycans on transferrin (Tf) in cerebrospinal fluid (CSF) using lectins and an anti-transferrin antibody (TfAb). Lectin blot and precipitation analysis of CSF revealed that PVL (Psathyrella velutina lectin) bound an unique N-acetylglucosamine-terminated N-glycans on "CSF-type" Tf whereas SSA (Sambucus sieboldiana agglutinin) bound α2,6-N-acetylneuraminic acid-terminated N-glycans on "serum-type" Tf. PVL-TfAb ELISA of 0.5 μL CSF samples detected "CSF-type" Tf but not "serum-type" Tf whereas SSA-TfAb ELISA detected "serum-type" Tf but not "CSF-type" Tf, demonstrating the specificity of the lectin-TfAb ELISAs. In idiopathic normal pressure hydrocephalus (iNPH), a senile dementia associated with ventriculomegaly, amounts of the SSA-reactive Tf were significantly higher than in non-iNPH patients, indicating that Tf glycan analysis by the high-throughput lectin-TfAb ELISAs could become practical diagnostic tools for iNPH. The lectin-antibody ELISAs of CSF proteins might be useful for diagnosis of the other neurological diseases.

  15. 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.

    PubMed

    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.

  16. Studies on a haemolymph lectin isolated from Rhodnius prolixus and its interaction with Trypanosoma rangeli.

    PubMed

    Mello, C B; Nigam, Y; Garcia, E S; Azambuja, P; Newton, R P; Ratcliffe, N A

    1999-04-01

    We demonstrated that in Rhodnius prolixus haemocyte monolayers, both Trypanosoma cruzi and Trypanosoma rangeli are capable of inducing haemocyte/parasite clump formation. We also purified, by one-step affinity chromatography, a haemolymph galactoside-binding lectin from R. prolixus which we believe could play an important role in the development of T. rangeli in the haemocoel of the insect vector. This lectin markedly enhanced the activation of clump formation by T. rangeli in R. prolixus haemocyte monolayers, with an increase in clump size and haemocyte aggregation. The haemolymph lectin also significantly affected the motilitity and survival of T. rangeli culture short forms, but not the long forms, when they were incubated in vitro. This molecule is also one of the few described in insects with agglutination activity independent of calcium ions. The partial N-terminal amino acid sequence of this lectin demonstrated similarity to a bacterial xylulose kinase and in preliminary experiments the purified haemolymph lectin phosphorylated a tyrosine kinase substrate in a dose-dependent manner. The possible role of this haemolymph lectin in the life cycle of T. rangeli is discussed. Copyright 1999 Academic Press.

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

    PubMed

    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.

  18. Plant Lectins: Wheat Defense Strategy Against Hessian Fly

    USDA-ARS?s Scientific Manuscript database

    Plants produce a variety of defense proteins, including lectins in response to attack by phytophagous insects. Ultrastructural studies reveal that binding to insect gut structures and resistance to proteolytic degradation by insect digestive enzymes are the two main prerequisites for the lectins to...

  19. 21 CFR 864.9550 - Lectins and protectins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... antigens. These substances are used to detect blood group antigens for in vitro diagnostic purposes. (b...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Products Used In Establishments That Manufacture Blood and Blood Products § 864.9550 Lectins and protectins. (a) Identification. Lectins and protectins are...

  20. Differentiation of Bacillus Anthracis and Other Bacillus Species by Use of Lectins

    DTIC Science & Technology

    1983-07-18

    TITL9 fAnd Subtfitle) S.TypeO REPORT gi PZRCC rvt 4 DIFFERENTIATION OF BACIL-LUSg’ ANTHRAtgACIS D OTHER BACILLUS , SPECIES BY-USE OYLECTINS" Inter[im...Ricinus communis. Some strains of Bacillus cer-eus var. m-ycoides (B. Mycoides) were strongly reactive with the lectin from Helbi pomtia and weakly reacti...ve with the Glycine max lectin. The differential iCnteractions between Bacillus species and lectins af forded a means of distinguishing B. anthracis

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

    PubMed

    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).

  2. Glycoconjugate pattern of membranes in the acinar cell of the rat pancreas.

    PubMed

    Willemer, S; Köhler, H; Naumann, R; Kern, H F; Adler, G

    1990-01-01

    Lectin-binding studies were performed at the ultrastructural level to characterize glycoconjugate patterns on membrane systems in pancreatic acinar cells of the rat. Five lectins reacting with different sugar moieties were applied to ultrathin frozen sections: concanavalin A (ConA): glucose, mannose; wheat-germ agglutinin (WGA): N-acetylglucosamine, sialic acid; Ricinus communis agglutinin I (RCA I): galactose; Ulex europaeus agglutinin I (UEA I): L-fucose; soybean agglutinin (SBA): N-acetylgalactosamine). Binding sites of lectins were visualized either by direct conjugation to colloidal gold or by the use of a three-step procedure involving additional immune reactions. The rough endoplasmic reticulum and the nuclear envelope of acinar cells was selectively labelled for ConA. The membranes of the Golgi apparatus bound all lectins applied with an increasing intensity proceeding from the cis- to the trans-Golgi area for SBA, UEA I and WGA. In contrast RCA I selectively labelled the trans-Golgi cisternae. The membranes of condensing vacuoles and zymogen granules were labelled for all lectins used although the density of the label differed between the lectins. In contrast the content of zymogen granules failed to bind SBA and WGA. Lysosomal bodies (membranes and content) revealed binding sites for all lectins used. The plasma membranes were heavily labelled by all lectins except for SBA which showed only a weak binding to the lateral and the apical plasma membrane. These results are in accordance to current biochemical knowledge of the successive steps in the glycosylation of membrane proteins. It could be demonstrated, that the cryo-section technique is suitable for the fine structural localisation of surface glycoconjugates of plasma membranes and internal membranes in pancreatic acinar cells using plant lectins.

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

    PubMed

    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.

  4. Effect of surface modifiers on an ectoenzyme: granulocyte 5'-nucleotidase.

    PubMed

    Smolen, J E; Karnovsky, M L

    1980-05-01

    Several agents that react with plasma membranes, namely the native lectins concanavalin A, Ricinus communis agglutinin, and wheat germ agglutinin, the modified lectin succinyl concanavalin A, and sodium meta-periodate, inhibited the ecto-5'-nucleotidase of intact guinea pig granulocytes. Stimulation of the enzyme was not observed at any lectin concentration. Inhibition by native lectins could be blocked or reversed by appropriate competing hapten sugars. In the case of concanavalin A, reversal could be achieved at 37 degrees C, but not at 5 degrees C. When lectins were used in combination with each other, the effects were found to be largely independent. However, when concanavalin A and R. communis agglutinin were applied together, complications arose because the former lectin binds to the latter as well as to the cell surface. To avoid some of the complexities inherent in studying intact cell 5'-nucleotidase and to gain additional information about the system, two broken cell enzyme preparations were also examined. The enzyme of plasma membrane-enriched fractions was inhibited by all five agents mentioned above. 5'-Nucleotidase solubilized in sodium deoxycholate was inhibited by the four lectins but stimulated by periodate. The effects of the surface modifiers on kinetic data for all three enzyme preparations are consistent with the hypothesis that direct interactions with the enzyme molecule give rise to changes in Vmax; interactions at membrane sites other than 5'-nucleotidase itself could cause increases in apparent Km values. Effects of interactions of ectoenzymes with plant lectins may serve as models for phenomena that result from cell-cell interactions or from interactions of animal cells with lectin-like components of the cellular environment.

  5. Lectins stain cells differentially in the coral, Montipora capitata

    USGS Publications Warehouse

    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.

  6. Insights into animal and plant lectins with antimicrobial activities.

    PubMed

    Dias, Renata de Oliveira; Machado, Leandro Dos Santos; Migliolo, Ludovico; Franco, Octavio Luiz

    2015-01-05

    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.

  7. Deficiency in Mannose-Binding Lectin-Associated Serine Protease-2 Does Not Increase Susceptibility to Trypanosoma cruzi Infection

    PubMed Central

    Ribeiro, Carolina H.; Lynch, Nicholas J.; Stover, Cordula M.; Ali, Youssif M.; Valck, Carolina; Noya-Leal, Francisca; Schwaeble, Wilhelm J.; Ferreira, Arturo

    2015-01-01

    Trypanosoma cruzi is the causative agent of Chagas' disease, a chronic illness affecting 10 million people around the world. The complement system plays an important role in fighting microbial infections. The recognition molecules of the lectin pathway of complement activation, mannose-binding lectin (MBL), ficolins, and CL-11, bind to specific carbohydrates on pathogens, triggering complement activation through MBL-associated serine protease-2 (MASP-2). Previous in vitro work showed that human MBL and ficolins contribute to T. cruzi lysis. However, MBL-deficient mice are only moderately compromised in their defense against the parasite, as they may still activate the lectin pathway through ficolins and CL-11. Here, we assessed MASP-2-deficient mice, the only presently available mouse line with total lectin pathway deficiency, for a phenotype in T. cruzi infection. Total absence of lectin pathway functional activity did not confer higher susceptibility to T. cruzi infection, suggesting that it plays a minor role in the immune response against this parasite. PMID:25548381

  8. Lectin from embryos and oocytes of Xenopus laevis. Purification and properties.

    PubMed

    Roberson, M M; Barondes, S H

    1982-07-10

    Soluble extracts of Xenopus laevis blastula stage embryos, oocytes, and adult liver contain lectin activities detected by agglutination of trypsinized, glutaraldehyde-fixed rabbit erythrocytes. Lectin from the embryos and oocytes was purified by affinity chromatography on a column derivatized with melibiose. Trace contaminants were removed either by preparative isoelectric focusing or by gel filtration. Based on its behavior on Sepharose 6B the purified oocyte lectin has an apparent molecular weight of approximately 480,000. On sodium dodecyl sulfate polyacrylamide gel electrophoresis under reducing conditions there were two major bands with molecular weight ranges of about 43,000 and 45,000, with diffuse trails. Since the purified lectin contains about 20% saccharides by weight and since both bands are glycosylated, diffuseness might be due to variable glycosylation. Heterogeneity was indicated by isoelectric focusing in polyacrylamide gels, which showed four protein bands with isoelectric points ranging from 4.4 to 4.9. Lectins from both embryos and oocytes comprised about 1 to 2% of the total soluble protein and could not be distinguished by sodium dodecyl sulfate polyacrylamide gel electrophoresis. However, the specific hemagglutination activity of the purified oocyte lectin was, on the average, 7-fold higher. Levels in crude extracts of liver were 3 orders of magnitude lower than those from oocytes. The hemagglutination activities of the lectins from embryos, oocytes, and adult liver required Ca2+ and were blocked by similar concentrations of both alpha- and beta-galactosides.

  9. Proteins with an Euonymus lectin-like domain are ubiquitous in Embryophyta

    PubMed Central

    2009-01-01

    Background Cloning of the Euonymus lectin led to the discovery of a novel domain that also occurs in some stress-induced plant proteins. The distribution and the diversity of proteins with an Euonymus lectin (EUL) domain were investigated using detailed analysis of sequences in publicly accessible genome and transcriptome databases. Results Comprehensive in silico analyses indicate that the recently identified Euonymus europaeus lectin domain represents a conserved structural unit of a novel family of putative carbohydrate-binding proteins, which will further be referred to as the Euonymus lectin (EUL) family. The EUL domain is widespread among plants. Analysis of retrieved sequences revealed that some sequences consist of a single EUL domain linked to an unrelated N-terminal domain whereas others comprise two in tandem arrayed EUL domains. A new classification system for these lectins is proposed based on the overall domain architecture. Evolutionary relationships among the sequences with EUL domains are discussed. Conclusion The identification of the EUL family provides the first evidence for the occurrence in terrestrial plants of a highly conserved plant specific domain. The widespread distribution of the EUL domain strikingly contrasts the more limited or even narrow distribution of most other lectin domains found in plants. The apparent omnipresence of the EUL domain is indicative for a universal role of this lectin domain in plants. Although there is unambiguous evidence that several EUL domains possess carbohydrate-binding activity further research is required to corroborate the carbohydrate-binding properties of different members of the EUL family. PMID:19930663

  10. Lectin-based food poisoning: a new mechanism of protein toxicity.

    PubMed

    Miyake, Katsuya; Tanaka, Toru; McNeil, Paul L

    2007-08-01

    Ingestion of the lectins present in certain improperly cooked vegetables can result in acute GI tract distress, but the mechanism of toxicity is unknown. In vivo, gut epithelial cells are constantly exposed to mechanical and other stresses and consequently individual cells frequently experience plasma membrane disruptions. Repair of these cell surface disruptions allows the wounded cell to survive: failure results in necrotic cell death. Plasma membrane repair is mediated, in part, by an exocytotic event that adds a patch of internal membrane to the defect site. Lectins are known to inhibit exocytosis. We therefore tested the novel hypothesis that lectin toxicity is due to an inhibitory effect on plasma membrane repair. Repair of plasma membrane disruptions and exocytosis of mucus was assessed after treatment of cultured cell models and excised segments of the GI tract with lectins. Plasma membrane disruptions were produced by focal irradiation of individual cells, using a microscope-based laser, or by mechanical abrasion of multiple cells, using a syringe needle. Repair was then assessed by monitoring the cytosolic penetration of dyes incapable of crossing the intact plasma membrane. We found that cell surface-bound lectins potently inhibited plasma membrane repair, and the exocytosis of mucus that normally accompanies the repair response. Lectins potently inhibit plasma membrane repair, and hence are toxic to wounded cells. This represents a novel form of protein-based toxicity, one that, we propose, is the basis of plant lectin food poisoning.

  11. 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

    PubMed Central

    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

  12. Characterization of mannose binding lectin from channel catfish Ictalurus punctatus

    USDA-ARS?s Scientific Manuscript database

    Mannose-binding lectin (MBL) is an important component of innate immunity capable of activating the lectin pathway of the complement system. A MBL gene was isolated from channel catfish (Ictalurus punctatus). The deduced protein contains a canonical collagen-like domain, a carbohydrate recognition d...

  13. [Comparative assessment of inductive effects of Azospirillum lectins with different antigenic properties on the signal systems of wheat seedling roots].

    PubMed

    Alen'kina, S A; Petrova, L P; Sokolova, M K; Chernyshova, M P; Trutneva, K A; Bogatyrev, V A; Nikitina, V E

    2014-01-01

    The lectins of associative nitrogen-fixing bacteria Azospirillum brasilense Sp7 and its mutant A. brasilense Sp7.2.3 were shown to have different effects on the components of the wheat seedling root signal system, namely to regulate the levels of cAMP, nitric oxide, diacylglycerol, and salicylic acid, as well as to induce the activities of superoxide dismutase and lipoxygenase. Our results make it possible to consider azospirilla lectins as inducers of the signal systems in wheat seedling roots, since they cause development of several flows of primary signals. These data are of general biological importance, since lectins are present in all living organisms and most ot the functions of lectins remain insufficiently understood.

  14. [Effect of thyroid hormones on the histotopography of lectin receptors in the rat salivary gland].

    PubMed

    Lutsik, A D; Iashchenko, A M; Detiuk, E S

    1987-04-01

    Using lectin-peroxidase technique, the influence of hypo- and hyperthyroidism on histotopography of glycoconjugates has been investigated in rat submandibular gland. The following lectins were used: peanut agglutinin (PNA), wheat germ agglutinin (WGA), Laburnum anagyroides lectin (LAL) and concanavalin A (con A). It has been demonstrated that hyperthyroidism is accompanied by the loss of con A, WGA and LAL receptor sites. Hypothyrodism enhanced con A binding to granular duct cells with a parallel reduction in WGA and LAL binding to these or other duct cells. Hypothyroidism as well as hyperthyroidism markedly enhanced PNA binding to duct epitheliocytes with redistribution of these lectin binding sites from the luminal surface of salivary ducts into the cytoplasm of duct cells. Possible interpretations of the observed phenomena are discussed.

  15. Structure and Function of Mammalian Carbohydrate-Lectin Interactions

    NASA Astrophysics Data System (ADS)

    Anderson, Kevin; Evers, David; Rice, Kevin G.

    Over the past three decades the field of glycobiology has expanded beyond a basic understanding of the structure and biosynthesis of glycoprotein, proteoglycans, and glycolipids toward a more detailed picture of how these molecules afford communication through binding to mammalian lectins. Although the number of different mammalian lectin domains appears to be finite and even much smaller than early estimates predicated based on the diversity of glycan structures, nature appears capable of using these in numerous combinations to fine tune specificity. The following provides an overview of the major classes of mammalian lectins and discusses their glycan binding specificity. The review provides a snapshot of the field of glycobiology that continues to grow providing an increasing number of examples of biological processes that rely upon glycan-lectin binding.

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

    PubMed Central

    Itakura, Yoko; Nakamura-Tsuruta, Sachiko; Kominami, Junko; Tateno, Hiroaki; Hirabayashi, Jun

    2017-01-01

    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. PMID:28556796

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

    PubMed

    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.

  18. Integrated Microfluidic Lectin Barcode Platform for High-Performance Focused Glycomic Profiling

    NASA Astrophysics Data System (ADS)

    Shang, Yuqin; Zeng, Yun; Zeng, Yong

    2016-02-01

    Protein glycosylation is one of the key processes that play essential roles in biological functions and dysfunctions. However, progress in glycomics has considerably lagged behind genomics and proteomics, due in part to the enormous challenges in analysis of glycans. Here we present a new integrated and automated microfluidic lectin barcode platform to substantially improve the performance of lectin array for focused glycomic profiling. The chip design and flow control were optimized to promote the lectin-glycan binding kinetics and speed of lectin microarray. Moreover, we established an on-chip lectin assay which employs a very simple blocking method to effectively suppress the undesired background due to lectin binding of antibodies. Using this technology, we demonstrated focused differential profiling of tissue-specific glycosylation changes of a biomarker, CA125 protein purified from ovarian cancer cell line and different tissues from ovarian cancer patients in a fast, reproducible, and high-throughput fashion. Highly sensitive CA125 detection was also demonstrated with a detection limit much lower than the clinical cutoff value for cancer diagnosis. This microfluidic platform holds the potential to integrate with sample preparation functions to construct a fully integrated “sample-to-answer” microsystem for focused differential glycomic analysis. Thus, our technology should present a powerful tool in support of rapid advance in glycobiology and glyco-biomarker development.

  19. Integrated Microfluidic Lectin Barcode Platform for High-Performance Focused Glycomic Profiling

    PubMed Central

    Shang, Yuqin; Zeng, Yun; Zeng, Yong

    2016-01-01

    Protein glycosylation is one of the key processes that play essential roles in biological functions and dysfunctions. However, progress in glycomics has considerably lagged behind genomics and proteomics, due in part to the enormous challenges in analysis of glycans. Here we present a new integrated and automated microfluidic lectin barcode platform to substantially improve the performance of lectin array for focused glycomic profiling. The chip design and flow control were optimized to promote the lectin-glycan binding kinetics and speed of lectin microarray. Moreover, we established an on-chip lectin assay which employs a very simple blocking method to effectively suppress the undesired background due to lectin binding of antibodies. Using this technology, we demonstrated focused differential profiling of tissue-specific glycosylation changes of a biomarker, CA125 protein purified from ovarian cancer cell line and different tissues from ovarian cancer patients in a fast, reproducible, and high-throughput fashion. Highly sensitive CA125 detection was also demonstrated with a detection limit much lower than the clinical cutoff value for cancer diagnosis. This microfluidic platform holds the potential to integrate with sample preparation functions to construct a fully integrated “sample-to-answer” microsystem for focused differential glycomic analysis. Thus, our technology should present a powerful tool in support of rapid advance in glycobiology and glyco-biomarker development. PMID:26831207

  20. Specific interactions between lectins and red blood cells of Chornobyl cleanup workers as indicator of some late radiation effects.

    PubMed

    Karpova, I S

    2016-12-01

    Growing interest in lectins is based on their diagnostic and pharmacological potential, especially the ability to inhibit proliferation and initiate apoptosis of cancer cells. In our research microplate lectinoassay able to detect carbohydrate containing structures (receptors) on erythrocyte surface have been proposed for Chornobyl cleanup workers (1986) monitoring. It was expected to reveal specific abnormalities associated with pathological condition arising as a result of late radiation effects. Red blood cell (RBC) specimens were taken from 171 persons distributed into the six cohorts: nonexposed donors (1); chronically exposed to the doses below (2) and over 50 cGy (3); exposed to acute radiation without (4) and with manifestation of acute radiation syndrome (5 and 6). Lectins from 24 species of medicinal plants were purified by ethanol fractionation and electrofocusing. Intensity of lectin-receptor interactions was determined in reaction of hemagglutination. Method of flow cytofluorometry was used to study B-cell counts. Hormone levels in blood serum were determined by radioimmunoassay. An elevated ability of RBC to interact with the panel of lectins was found in all cohorts of exposed persons versus nonexposed donors, moreover, changes in the intensity of lectin-receptor binding depended on the dose of irradiation. Diagnostic value of specific RBC reactions with some individual lectins has been elucidated. Elevated intensity of RBC reaction with Zea mays lectin was accompanied by a decrease in serum content of thyroid hormones T4 and T3, as well as reduction of B-cell counts. In the case of Rubus caesius lectin the more intensive reaction with RBC, the higher level of hormone cortisol was observed. Deviations from donor's norm in intensity of lectin - RBC interactions in radiation exposed men are supposed to carry information about negative changes in their health status following Chornobyl catastrophe and show the diagnostic potential. The most sensitive reactions have been associated primarily with shifts in endocrine and immune systems. This article is a part of a Special Issue entitled "The Chornobyl Nuclear Accident: Thirty Years After".

  1. cDNA cloning, molecular modeling and docking calculations of L-type lectins from Swartzia simplex var. grandiflora (Leguminosae, Papilionoideae), a member of the tribe Swartzieae.

    PubMed

    Maranhão, Paulo A C; Teixeira, Claudener S; Sousa, Bruno L; Barroso-Neto, Ito L; Monteiro-Júnior, José E; Fernandes, Andreia V; Ramos, Marcio V; Vasconcelos, Ilka M; Gonçalves, José F C; Rocha, Bruno A M; Freire, Valder N; Grangeiro, Thalles B

    2017-07-01

    The genus Swartzia is a member of the tribe Swartzieae, whose genera constitute the living descendants of one of the early branches of the papilionoid legumes. Legume lectins comprise one of the main families of structurally and evolutionarily related carbohydrate-binding proteins of plant origin. However, these proteins have been poorly investigated in Swartzia and to date, only the lectin from S. laevicarpa seeds (SLL) has been purified. Moreover, no sequence information is known from lectins of any member of the tribe Swartzieae. In the present study, partial cDNA sequences encoding L-type lectins were obtained from developing seeds of S. simplex var. grandiflora. The amino acid sequences of the S. simplex grandiflora lectins (SSGLs) were only averagely related to the known primary structures of legume lectins, with sequence identities not greater than 50-52%. The SSGL sequences were more related to amino acid sequences of papilionoid lectins from members of the tribes Sophoreae and Dalbergieae and from the Cladratis and Vataireoid clades, which constitute with other taxa, the first branching lineages of the subfamily Papilionoideae. The three-dimensional structures of 2 representative SSGLs (SSGL-A and SSGL-E) were predicted by homology modeling using templates that exhibit the characteristic β-sandwich fold of the L-type lectins. Molecular docking calculations predicted that SSGL-A is able to interact with D-galactose, N-acetyl-D-galactosamine and α-lactose, whereas SSGL-E is probably a non-functional lectin due to 2 mutations in the carbohydrate-binding site. Using molecular dynamics simulations followed by density functional theory calculations, the binding free energies of the interaction of SSGL-A with GalNAc and α-lactose were estimated as -31.7 and -47.5 kcal/mol, respectively. These findings gave insights about the carbohydrate-binding specificity of SLL, which binds to immobilized lactose but is not retained in a matrix containing D-GalNAc as ligand. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Molecular dynamics simulations of pea (Pisum sativum) lectin structure with octyl glucoside detergents: the ligand interactions and dynamics.

    PubMed

    Konidala, Praveen; Niemeyer, Bernd

    2007-07-01

    The mitogenic pea (Pisum sativum) lectin is a legume protein of non-immunoglobulin nature capable of specific recognition of glucose derivatives without altering its structure. Molecular dynamics simulations were performed in a realistic environment to investigate the structure and interaction properties of pea lectin with various concentrations of n-octyl-beta-d-glucopyranoside (OG) detergent monomers distributed inside explicit solvent cell. In addition, the diffusion coefficients of the ligands (OG, Ca2+, Mn2+, and Cl-) and the water molecules were also reported. The structural flexibility of the lectin was conserved in all simulations. The self-assembly of OG monomers into a small micelle at the hydrophobic site of the lectin was noticed in the simulation with 20 OG monomers. The interaction energy analysis concludes that the lectin was appropriately termed an adaptive structure. One or rarely two binding sites were observed at an instant in each simulation that were electrostatically favoured for the OG to interact with the surface amino acid residues. Enhanced binding of OG to the pea lectin was quantified in the system containing only Ca2+ divalent ions. Interestingly, no binding was observed in the simulation without divalent ions. Furthermore, the lectin-ligand complex was stabilized by multiple hydrogen bonds and at least one water bridge. Finally, the work was also in accordance with the published work elsewhere that the simulations performed with different initial conditions and using higher nonbonded cutoffs for the van der Waals and electrostatic interactions provide more accurate information and clues than the single large simulation of the biomolecular system of interest.

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

    PubMed

    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.

  4. A comparative study of lectin affinity based plant n-glycoproteome profiling using tomato fruit as a model

    USDA-ARS?s Scientific Manuscript database

    Lectin affinity chromatography (LAC) can provide a valuable front-end enrichment strategy for the study of N-glycoproteins and has been used to characterize a broad range eukaryotic N-glycoproteomes. Moreover, studies with mammalian systems have suggested that the use of multiple lectins with differ...

  5. Lectin histochemistry of the rat lymph node: visualisation of stroma, blood vessels, sinuses, and macrophages. A contribution to the concept of an immune accessory role of sinus-lining endothelia.

    PubMed

    Düllmann, Jochen; Van Damme, Els J M; Peumans, Willy J; Ziesenitz, Maike; Schumacher, Udo

    2002-01-01

    The lectin Chelidonium majus agglutinin (CMA) was previously shown to visualise endothelia of all blood vessels and those lining sinuses of red pulp, stromal reticular meshwok (RM) and dendritic cells of lymphatic follicles in white pulp of the spleen in rats. The aim of the present study was the analysis of CMA and some other lectins in labelling RM, vascular structures and macrophages in lymph nodes of rats. It appeared that CMA stained the entire RM, dendritic cells, lining cells of sinuses and all types of blood vessels. Sinus-lining cells of lymph nodes were labelled with CMA and mannose-, GalNac-, and sialic acid-specific lectins. Moreover, lymph node macrophages were labelled above all by mannose specific lectins. The broad lectin-binding pattern of sinuses--not observed in rat spleen- and CMA-reactivity of both sinus-lining and dendritic cells corroborates the hypothesis that lymph node sinus-lining endothelia are precursors or a special type of immune accessory cells.

  6. A descriptive and comparative lectin histochemical study of the vomeronasal system in pigs and sheep

    PubMed Central

    SALAZAR, IGNACIO; SANCHEZ-QUINTEIRO, PABLO; LOMBARDERO, MATILDE; CIFUENTES, JOSE MANUEL

    2000-01-01

    The accessory olfactory bulb (AOB) is the primary target of the sensory epithelium of the vomeronasal organ (VNO), and thus constitutes a fundamental component of the accessory olfactory system, which is involved in responses to behaviour-related olfactory stimuli. In this study we investigated the characteristics of the AOB, VNO, vomeronasal nerves (VNNs) and caudal nasal nerve (CdNN) in pigs and sheep, species in which olfaction plays a key behavioural role both in the neonatal period and in adulthood. The patterns of staining of the AOB by the Bandeiraea simplicifolia and Lycopersicon esculentum lectins were the same in the 2 species, whereas the Ulex europeus and Dolichos biflorus lectins gave different patterns. In both species, lectin staining of the AOB was consistent with that of the VNNs, while the CdNN did not label any of the structures studied. The entire sensory epithelium of the pig was labelled by Ulex europeus and Lycopersicum esculentum lectins, and all 4 lectins used labelled the mucomicrovillar surface of the sensory epithelium in sheep. PMID:10697284

  7. A simple procedure for the isolation of L-fucose-binding lectins from Ulex europaeus and Lotus tetragonolobus.

    PubMed

    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.

  8. Sea bass Dicentrarchus labrax (L.) bacterial infection and confinement stress acts on F-type lectin (DlFBL) serum modulation.

    PubMed

    Parisi, M G; Benenati, G; Cammarata, M

    2015-11-01

    The F-lectin, a fucose-binding protein found from invertebrates to ectothermic vertebrates, is the last lectin family to be discovered. Here, we describe effects of two different types of stressors, bacterial infection and confinement stress, on the modulation of European sea bass Dicentrarchus labrax (L.) F-lectin (DlFBL), a well-characterized serum opsonin, using a specific antibody. The infection of the Vibrio alginolyticus bacterial strain increased the total haemagglutinating activity during the 16-day testing period. The DlFBL value showed an upward regulation on the first, second and last days and underwent a slight downward regulation 4 days post-challenge. In contrast, the effect of confinement and density stress showed a decrease in the plasma concentration of lectin, ranging from 50% to 60% compared with the control. The modulation of DlFBL is in line with the hypothesis that humoral lectins could be involved and recruited in the initial recognition step of the inflammation, which leads to agglutination, and the activation of mechanisms responsible for killing of the pathogens. © 2014 John Wiley & Sons Ltd.

  9. Effect of the lectin of Bauhinia variegata and its recombinant isoform on surgically induced skin wounds in a murine model.

    PubMed

    Neto, Luiz Gonzaga do Nascimento; Pinto, Luciano da Silva; Bastos, Rafaela Mesquita; Evaristo, Francisco Flávio Vasconcelos; Vasconcelos, Mayron Alves de; Carneiro, Victor Alves; Arruda, Francisco Vassiliepe Sousa; Porto, Ana Lúcia Figueiredo; Leal, Rodrigo Bainy; Júnior, Valdemiro Amaro da Silva; Cavada, Benildo Sousa; Teixeira, Edson Holanda

    2011-11-07

    Lectins are a structurally heterogeneous group of highly specific carbohydrate-binding proteins. Due to their great biotechnological potential, lectins are widely used in biomedical research. The purpose of the present study was to evaluate the healing potential of the lectin of Bauhinia variegata (nBVL) and its recombinant isoform (rBVL-1). Following surgical creation of dorsal skin wounds, seven groups of mice were submitted to topical treatment for 12 days with lectin, D-galactose, BSA and saline. The animals were anesthetized and euthanized on POD 2, 7 and 12 in order to evaluate the healing potential of each treatment. The parameters considered included wound size, contraction rate, epithelialization rate and histopathological findings. Wound closure was fastest in animals treated with rBVL-1 (POD 7). nBVL was more effective than the controls. All skin layers were reconstructed and keratin deposition increased. Our findings indicate that the lectin of Bauhinia variegata possesses pro-healing properties and may be employed in the treatment of acute skin wounds.

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

    PubMed

    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.

  11. Temperature effect on affinity chromatography of two lectins from the seeds of Ricinus communis

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

    Hsu, H.W.; Davis, D.S.; Wei, C.H.

    1976-06-01

    Specific adsorption capacity of Sepharose 4B in affinity chromatography for two purified galactose-binding lectins, designated as III/sub L/ and III/sub H/, from the seed of Ricinus communis (castor bean) was measured from 7 to 24/sup 0/C. The adsorption coefficients for these two protein fractions as a function of temperature were also obtained. It was found that there is a characteristic transition of adsorption coefficient at 18/sup 0/C for both lectins. Adsorption coefficients between Sepharose 4B and these two lectins were also expressed in terms of ..delta..G, ..delta..H, and ..delta..S. It is suggested that the difference in the temperature dependence ofmore » the binding energy of these two lectins may be used for their separation at selected temperature.« less

  12. Carbohydrate binding specificity of pea lectin studied by NMR spectroscopy and molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Cheong, Youngjoo; Shim, Gyuchang; Kang, Dongil; Kim, Yangmee

    1999-02-01

    The conformational details of Man( α1,6)Man( α)OMe are investigated through NMR spectroscopy in conjunction with molecular modeling. The lowest energy structure (M1) in the adiabatic energy map calculated with a dielectric constant of 50 has glycosidic dihedral angles of φ=-60°, ψ=180° and ω=180°. The other low energy structure (M2) has glycosidic dihedral angles of φ=-60°, ψ=180° and ω=-60°. Molecular dynamics simulations and NMR experiments prove that Man( α1,6)Man( α)OMe in the free form exists with conformational averaging of M1 and M2 conformers predominantly. Molecular dynamics simulations of the pea lectin-carbohydrate complex with explicit water molecules starting from the X-ray crystallographic structure of pea lectin show that the protein-carbohydrate interaction centers mainly on the hydrogen bonds and van der Waals interactions between protein and carbohydrate. From the molecular dynamics simulation, it is found that the M1 structure can bind to pea lectin better than the M2 structure. The origin of this selectivity is the water- mediated hydrogen bond interactions between the remote mannose and the binding site of pea lectin as well as the direct hydrogen bond interaction between the terminal mannose and pea lectin. Extensive networks of interactions in the carbohydrate binding site and the metal binding site are important in maintaining the carbohydrate binding properties of pea lectin. Especially, the predominant factors of mannose binding specificity of pea lectin are the hydrogen bond interactions between the 4th hydroxyl groups of the terminal sugar ring and the side chains of Asp-81 and Asn-125 in the carbohydrate binding site, and the additional interactions between these side chains of Asp-81 and Asn-125 and the calcium ion in the metal binding site of pea lectin.

  13. Structure Predictions of Two Bauhinia variegata Lectins Reveal Patterns of C-Terminal Properties in Single Chain Legume Lectins

    PubMed Central

    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. PMID:24260572

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

    PubMed

    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.

  15. Ulex europaeus I and glycine max bind to the human olfactory bulb.

    PubMed

    Nagao, M; Oka, N; Kamo, H; Akiguchi, I; Kimura, J

    1993-12-24

    The distribution of binding sites for the fucose-selective lectin Ulex europaeus I and the terminal N-acetylgalactosamine-selective lectin glycine max in the human olfactory bulb were studied. These lectins bound to primary olfactory axons in the olfactory nerve layer and the glomerular layer. They also bound to fibers located in the deeper layers such as the external plexiform layer and the granular layer. Furthermore they projected to the olfactory stalk but not in the cerebrum. The deeper projections of the lectin binding fibers may affect the function of the olfactory bulb in humans.

  16. The Structure of the Neurotoxin- Associated Protein HA33/A from Clostridium botulinum Suggests a Reoccurring Beta-Trefoil Fold in the Progenitor Toxin Complex

    DTIC Science & Technology

    2004-12-16

    mistletoe lectin I. The ricin and mistle- toe lectin I structures revealed a domain architec- ture that are similar to HA33/A with two b-trefoil...domains. The complex crystal structures of ricin bound to lactose and mistletoe lectin I bound to galactose revealed that only the 1a and 2g repeats of...H., Tonevitsky, A. G., Agapov, I. I., Saward, S., Pfuller, U. & Palmer, R. A. (2003). Crystal structure at 3 Å of mistletoe lectin I, a dimeric

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

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

    Feng, K.; College of Food Science, Heilongjiang August First Land Reclamation University, Daqing 163319; Liu, Q.H.

    2006-07-14

    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{sub 4}){sub 2}SO{sub 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 {sup o}C but was acid- and alkali-labile. Salts including FeCl{sub 3}, AlCl{sub 3}, and ZnCl{sub 2} inhibited the activity whereas MgCl{sub 2},more » MnCl{sub 2}, and CaCl{sub 2} did not. The lectin stimulated mitogenic response of mouse splenocytes with the maximal response achieved by 1 {mu}M lectin. Proliferation of tumor cells including MBL2 cells, HeLa cells, and L1210 cells was inhibited by the lectin with an IC{sub 5} of 2.5, 5, and 10 {mu}M, 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.« less

  18. Lectin histochemistry as a tool to identify apoptotic cells in the seminiferous epithelium of Syrian hamster (Mesocricetus auratus) subjected to short photoperiod.

    PubMed

    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.

  19. A new TRAF-like protein from B. oleracea ssp. botrytis with lectin activity and its effect on macrophages.

    PubMed

    Duarte, Christiane E M; Abranches, Monise V; Silva, Patrick F; de Paula, Sérgio O; Cardoso, Silvia A; Oliveira, Leandro L

    2017-01-01

    Lectins are involved in a wide range of biological mechanisms, like immunomodulatory agent able to activate the innate immunity. In this study, we purified and characterized a new lectin from cauliflower (Brassica oleracea ssp. botrytis - BOL) by three sequential chromatographic steps and confirmed the purity by SDS-PAGE. Additionally, we evaluated the role of the lectin in innate immunity by a phagocytosis assay, production of H 2 O 2 and NO. BOL was characterized like a non-glycosylated protein that showed a molecular mass of ∼34kDa in SDS-PAGE. Its N-terminal sequence (ETRAFREERPSSKIVTIAG) did not reveal any similarity to the other lectins; nevertheless, it showed 100% homology to a putative TRAF-like protein from Brassica rapa and Brassica napus. This is a first report of the TRAF-protein with lectinic activity. The BOL retained its complete hemagglutination activity from 4°C up to 60°C, with stability being more apparent between pH 7.0 and 8.0. Moreover, the lectin was able to stimulate phagocytosis and induce the production of H 2 O 2 and NO. Therefore, BOL can be explored as an immunomodulatory agent by being able to activate the innate immunity and favor antigen removal. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. A lectin-coupled, targeted proteomic mass spectrometry (MRM MS) platform for identification of multiple liver cancer biomarkers in human plasma.

    PubMed

    Ahn, Yeong Hee; Shin, Park Min; Oh, Na Ree; Park, Gun Wook; Kim, Hoguen; Yoo, Jong Shin

    2012-09-18

    Aberrantly glycosylated proteins related to liver cancer progression were captured with specific lectin and identified from human plasma by multiple reaction monitoring (MRM) mass spectrometry as multiple biomarkers for hepatocellular carcinoma (HCC). The lectin fractionation for fucosylated protein glycoforms in human plasma was conducted with a fucose-specific aleuria aurantia lectin (AAL). Following tryptic digestion of the lectin-captured fraction, plasma samples from 30 control cases (including 10 healthy, 10 hepatitis B virus [HBV], and 10 cirrhosis cases) and 10 HCC cases were quantitatively analyzed by MRM to identify which glycoproteins are viable HCC biomarkers. A1AG1, AACT, A1AT, and CERU were found to be potent biomarkers to differentiate HCC plasma from control plasmas. The AUROC generated independently from these four biomarker candidates ranged from 0.73 to 0.92. However, the lectin-coupled MRM assay with multiple combinations of biomarker candidates is superior statistically to those generated from the individual candidates with AUROC more than 0.95, which can be an alternative to the immunoassay inevitably requiring tedious development of multiple antibodies against biomarker candidates to be verified. Eventually the lectin-coupled, targeted proteomic mass spectrometry (MRM MS) platform was found to be efficient to identify multiple biomarkers from human plasma according to cancer progression. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Crystal structure of Pisum arvense seed lectin (PAL) and characterization of its interaction with carbohydrates by molecular docking and dynamics.

    PubMed

    Pinto-Junior, Vanir Reis; Santiago, Mayara Queiroz; Nobre, Camila Bezerra; Osterne, Vinicius Jose Silva; Leal, Rodrigo Bainy; Cajazeiras, Joao Batista; Lossio, Claudia Figueiredo; Rocha, Bruno Anderson Matias; Martins, Maria Gleiciane Queiroz; Nobre, Clareane Avelino Simplicio; Silva, Mayara Torquato Lima; Nascimento, Kyria Santiago; Cavada, Benildo Sousa

    2017-09-15

    The Pisum arvense lectin (PAL), a legume protein belonging to the Vicieae tribe, is capable of specific recognition of mannose, glucose and its derivatives without altering its structure. In this work, the three-dimensional structure of PAL was determined by X-ray crystallography and studied in detail by a combination of molecular docking and molecular dynamics (MD). Crystals belonging to monoclinic space group P2 1 were grown by the vapor diffusion method at 293 K. The structure was solved at 2.16 Å and was similar to that of other Vicieae lectins. The structure presented R factor and R free of 17.04% and 22.08%, respectively, with all acceptable geometric parameters. Molecular docking was performed to analyze interactions of the lectin with monosaccharides, disaccharides and high-mannose N-glycans. PAL demonstrated different affinities on carbohydrates, depending on bond orientation and glycosidic linkage present in ligands. Furthermore, the lectin interacted with representative N-glycans in a manner consistent with the biological effects described for Vicieae lectins. Carbohydrate-recognition domain (CRD) in-depth analysis was performed by MD, describing the behavior of CRD residues in complex with ligand, stability, flexibility of the protein over time, CRD volume and topology. This is a first report of its kind for a lectin of the Vicieae tribe. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    PubMed

    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.

  3. Water-soluble Moringa oleifera lectin interferes with growth, survival and cell permeability of corrosive and pathogenic bacteria.

    PubMed

    Moura, M C; Napoleão, T H; Coriolano, M C; Paiva, P M G; Figueiredo, R C B Q; Coelho, L C B B

    2015-09-01

    This work evaluated the antibacterial activity of a water-soluble Moringa oleifera seed lectin (WSMoL) by evaluating its effect on growth, survival and cell permeability of Bacillus sp., Bacillus cereus, Bacillus pumillus, Bacillus megaterium, Micrococcus sp., Pseudomonas sp., Pseudomonas fluorescens, Pseudomonas stutzeri and Serratia marcescens. In addition, the effect of lectin on membrane integrity of most sensitive species was also evaluated. All the tested bacteria are able to cause biocorrosion and some are also responsible for human infections. WSMoL inhibited the bacterial growth, induced agglutination and promoted the leakage of proteins from cells of all strains. Bactericidal effect was detected against Bacillus sp., B. pumillus, B. megaterium, Ps. fluorescens and Ser. marcescens. The bacteriostatic effect of lectin was evident with only 6 h of incubation. Fluorescence microscopy of Ser. marcescens showed that WSMoL caused loss of cell integrity and indicated an anti-biofilm activity of the lectin. WSMoL was active against the bacteria by inhibiting growth and affecting cell permeability. The lectin also interfered with membrane integrity of Ser. marcescens, the most sensitive species. The study indicates that WSMoL was active against bacteria that cause serious problems in both industrial and health sectors. Also, the study contributes for the 'state-of-art' on antibacterial mechanisms of lectins. © 2015 The Society for Applied Microbiology.

  4. Localization of binding sites of Ulex europaeus I, Helix pomatia and Griffonia simplicifolia I-B4 lectins and analysis of their backbone structures by several glycosidases and poly-N-acetyllactosamine-specific lectins in human breast carcinomas.

    PubMed

    Ito, N; Imai, S; Haga, S; Nagaike, C; Morimura, Y; Hatake, K

    1996-09-01

    Several studies have shown the deletion of blood group A or B antigens and the accumulation of H antigens in human breast carcinomas. Other studies have independently demonstrated that the binding sites of lectins such as Helix pomatia agglutinin (HPA) and Griffonia simplicifolia agglutinin I-B4 (GSAI-B4) are highly expressed in these cells. In order to clarify the molecular mechanisms of malignant transformation and metastasis of carcinoma cells, it is important to understand the relationship between such phenotypically distinct events. For this purpose, we examined whether the binding sites of these lectins and Ulex europaeus agglutinin I (UEA-I) are expressed concomitantly in the same carcinoma cells and analyzed their backbone structures. The expression of the binding sites of these lectins was observed independently of the blood group (ABO) of the patients and was not affected by the histological type of the carcinomas. Observation of serial sections stained with these lectins revealed that the distribution of HPA binding sites was almost identical to that of GSAI-B4 in most cases. Furthermore, in some cases, UEA-I binding patterns were similar to those of HPA and GSAI-B4 but in other cases, mosaic staining patterns with these lectins were also observed, i.e., some cell clusters were stained with both HPA and GSAI-B4 but not with UEA-I and adjacent cell clusters were stained only with UEA-I. Digestion with endo-beta-galactosidase or N-glycosidase F markedly reduced the staining intensity of these lectins. Together with the reduction of staining by these lectins, reactivity with Griffonia simplicifolia agglutinin II appeared in carcinoma cells following endo-beta-galactosidase digestion. Among the lectins specific to poly-N-acetyllactosamine, Lycopersicon esculentum agglutinin (LEA) most vividly and consistently stained the cancer cells. Next to LEA, pokeweed mitogen agglutinin was also effective in staining these cells. Carcinoma cells reactive with these lectins corresponded well to those stained with both HPA and GSAI-B4, and in some cases, with UEA-I. These results demonstrate that the binding sites of UEA-I, HPA, and GSAI-B4 are expressed concomitantly in the same carcinoma cells and all carry linear and branched poly-N-acetyllactosamine on N-glycans, suggesting that the synthesis of this complex carbohydrate is one of the most important and basic processes leading to the malignant transformation of cells, invasion, and metastasis of carcinoma cells.

  5. A Lectin from Platypodium elegans with Unusual Specificity and Affinity for Asymmetric Complex N-Glycans*

    PubMed Central

    Benevides, Raquel Guimarães; Ganne, Géraldine; Simões, Rafael da Conceição; Schubert, Volker; Niemietz, Mathäus; Unverzagt, Carlo; Chazalet, Valérie; Breton, Christelle; Varrot, Annabelle; Cavada, Benildo Sousa; Imberty, Anne

    2012-01-01

    Lectin activity with specificity for mannose and glucose has been detected in the seed of Platypodium elegans, a legume plant from the Dalbergieae tribe. The gene of Platypodium elegans lectin A has been cloned, and the resulting 261-amino acid protein belongs to the legume lectin family with similarity with Pterocarpus angolensis agglutinin from the same tribe. The recombinant lectin has been expressed in Escherichia coli and refolded from inclusion bodies. Analysis of specificity by glycan array evidenced a very unusual preference for complex type N-glycans with asymmetrical branches. A short branch consisting of one mannose residue is preferred on the 6-arm of the N-glycan, whereas extensions by GlcNAc, Gal, and NeuAc are favorable on the 3-arm. Affinities have been obtained by microcalorimetry using symmetrical and asymmetrical Asn-linked heptasaccharides prepared by the semi-synthetic method. Strong affinity with Kd of 4.5 μm was obtained for both ligands. Crystal structures of Platypodium elegans lectin A complexed with branched trimannose and symmetrical complex-type Asn-linked heptasaccharide have been solved at 2.1 and 1.65 Å resolution, respectively. The lectin adopts the canonical dimeric organization of legume lectins. The trimannose bridges the binding sites of two neighboring dimers, resulting in the formation of infinite chains in the crystal. The Asn-linked heptasaccharide binds with the 6-arm in the primary binding site with extensive additional contacts on both arms. The GlcNAc on the 6-arm is bound in a constrained conformation that may rationalize the higher affinity observed on the glycan array for N-glycans with only a mannose on the 6-arm. PMID:22692206

  6. Safety testing of GM-rice expressing PHA-E lectin using a new animal test design.

    PubMed

    Poulsen, Morten; Schrøder, Malene; Wilcks, Andrea; Kroghsbo, Stine; Lindecrona, Rikke Hvid; Miller, Andreas; Frenzel, Thomas; Danier, Jürgen; Rychlik, Michael; Shu, Qingyao; Emami, Kaveh; Taylor, Mark; Gatehouse, Angharad; Engel, Karl-Heinz; Knudsen, Ib

    2007-03-01

    The 90-day animal study is the core study for the safety assessment of genetically modified foods in the SAFOTEST project. The model compound tested in the 90-day study was a rice variety expressing the kidney bean Phaseolus vulgaris lectin agglutinin E-form (PHA-E lectin). Female Wistar rats were given a nutritionally balanced purified diet with 60% parental rice, 60% PHA-E rice or 60% PHA-E rice spiked with 0.1% recombinant PHA-E lectin for 90 days. This corresponded to a mean daily PHA-E lectin intake of approximately 0, 30 and 100mg/kg body weight for each group, respectively. The spiking was used to increase the specificity and to demonstrate the sensitivity of the study. A range of biological, biochemical, microbiological and pathological parameters were examined and significant differences in weight of small intestine, stomach and pancreas and plasma biochemistry were seen between groups. Included in this paper are also data from the molecular characterisation and chemical analysis of the PHA-E rice, from the construction and production of the PHA-E lectin, and from the preceding 28-day in vivo study where the toxicity of the pure PHA-E lectin was determined. In conclusion, the combined use of information from the compositional analysis, the 28-day study and the characterisation of the PHA-E rice and the PHA-E lectin has improved the design of the 90-day study. The spiking procedure has facilitated the interpretation of the results of the study and transferred it into a valuable tool for the future safety testing of genetically modified foods.

  7. Purification, Biochemical Characterization, and Amino Acid Sequence of a Novel Type of Lectin from Aplysia dactylomela Eggs with Antibacterial/Antibiofilm Potential.

    PubMed

    Carneiro, Rômulo Farias; Torres, Renato Cézar Farias; Chaves, Renata Pinheiro; de Vasconcelos, Mayron Alves; de Sousa, Bruno Lopes; Goveia, André Castelo Rodrigues; Arruda, Francisco Vassiliepe; Matos, Maria Nágila Carneiro; Matthews-Cascon, Helena; Freire, Valder Nogueira; Teixeira, Edson Holanda; Nagano, Celso Shiniti; Sampaio, Alexandre Holanda

    2017-02-01

    A new lectin from Aplysia dactylomela eggs (ADEL) was isolated by affinity chromatography on HCl-activated Sepharose™ media. Hemagglutination caused by ADEL was inhibited by several galactosides, mainly galacturonic acid (Ka = 6.05 × 10 6  M -1 ). The primary structure of ADEL consists of 217 residues, including 11 half-cystines involved in five intrachain and one interchain disulfide bond, resulting in a molecular mass of 57,228 ± 2 Da, as determined by matrix-assisted laser desorption/ionization time of flight mass spectrometry. ADEL showed high similarity with lectins isolated from Aplysia eggs, but not with other known lectins, indicating that these lectins could be grouped into a new family of animal lectins. Three glycosylation sites were found in its polypeptide backbone. Data from peptide-N-glycosidase F digestion and MS suggest that all oligosaccharides attached to ADEL are high in mannose. The secondary structure of ADEL is predominantly β-sheet, and its tertiary structure is sensitive to the presence of ligands, as observed by CD. A 3D structure model of ADEL was created and shows two domains connected by a short loop. Domain A is composed of a flat three-stranded and a curved five-stranded β-sheet, while domain B presents a flat three-stranded and a curved four-stranded β-sheet. Molecular docking revealed favorable binding energies for interactions between lectin and galacturonic acid, lactose, galactosamine, and galactose. Moreover, ADEL was able to agglutinate and inhibit biofilm formation of Staphylococcus aureus, suggesting that this lectin may be a potential alternative to conventional use of antimicrobial agents in the treatment of infections caused by Staphylococcal biofilms.

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

    PubMed

    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.

  9. Cytotoxicity of Crude Lectins from Red Macroalgae from the Southern Coast of Java Island, Gunung Kidul Regency, Yogyakarta, Indonesia

    NASA Astrophysics Data System (ADS)

    Anam, C.; Chasanah, E.; Perdhana, B. P.; Fajarningsih, ND; Yusro, N. F.; Sari, A. M.; Nursiwi, A.; Praseptiangga, D.; Yunus, A.

    2017-04-01

    Lectins or carbohydrate-binding proteins, are widely distributed in nature, including in marine algae. It may have been considered that binding specificity of lectins to some carbohydrates provokes to produce many unique biological activities, including cell agglutination, mitogenic activity, and antitumor activity. The aim of this study was to determine the cytotoxicity of crude lectins from red macroalgae collected from the southern coast of Java Island, Gunung Kidul Regency, Yogyakarta against MCF-7 and HeLa cancer cells. In vitro MTT assay was used in this study. The results showed that less than 50% of MCF-7 and HeLa cancer cells growth were inhibited by the crude lectins from five species of red macro algae used in this study. The highest inhibition ability shown in the red alga A. nana was able to kill 47.68% of HeLa cervical cancer cells.

  10. Plant Lectins and Lectin Receptor-Like Kinases: How Do They Sense the Outside?

    PubMed Central

    Bellande, Kevin; Bono, Jean-Jacques; Savelli, Bruno; Jamet, Elisabeth; Canut, Hervé

    2017-01-01

    Lectins are fundamental to plant life and have important roles in cell-to-cell communication; development and defence strategies. At the cell surface; lectins are present both as soluble proteins (LecPs) and as chimeric proteins: lectins are then the extracellular domains of receptor-like kinases (LecRLKs) and receptor-like proteins (LecRLPs). In this review; we first describe the domain architectures of proteins harbouring G-type; L-type; LysM and malectin carbohydrate-binding domains. We then focus on the functions of LecPs; LecRLKs and LecRLPs referring to the biological processes they are involved in and to the ligands they recognize. Together; LecPs; LecRLKs and LecRLPs constitute versatile recognition systems at the cell surface contributing to the detection of symbionts and pathogens; and/or involved in monitoring of the cell wall structure and cell growth. PMID:28561754

  11. Ulex europaeus I lectin as a marker for vascular endothelium in human tissues.

    PubMed

    Holthöfer, H; Virtanen, I; Kariniemi, A L; Hormia, M; Linder, E; Miettinen, A

    1982-07-01

    Ulex europaeus I agglutinin, a lectin specific for some alpha-L-fucose-containing glycocompounds, was used in fluorescence microscopy to stain cryostat sections of human tissues. The endothelium of vessels of all sizes was stained ubiquitously in all tissues studied as judged by double staining with a known endothelial marker, antibodies against human clotting factor VIII. Cultured human umbilical vein endothelial cells, but not fibroblasts, also bound Ulex lectin. The staining was not affected by the blood group type of the tissue donor. In some tissues Ulex lectin presented additional binding to epithelial structures. Also, this was independent on the blood group or the ability of the tissue donor to secrete soluble blood group substances. Lotus tetragonolobus agglutinin, another lectin specific for some alpha-L-fucose-containing moieties failed to react with endothelial cells. Our results suggest that Ulex europaeus I agglutinin is a good histologic marker for endothelium in human tissues.

  12. Plant Lectins and Lectin Receptor-Like Kinases: How Do They Sense the Outside?

    PubMed

    Bellande, Kevin; Bono, Jean-Jacques; Savelli, Bruno; Jamet, Elisabeth; Canut, Hervé

    2017-05-31

    Lectins are fundamental to plant life and have important roles in cell-to-cell communication; development and defence strategies. At the cell surface; lectins are present both as soluble proteins (LecPs) and as chimeric proteins: lectins are then the extracellular domains of receptor-like kinases (LecRLKs) and receptor-like proteins (LecRLPs). In this review; we first describe the domain architectures of proteins harbouring G-type; L-type; LysM and malectin carbohydrate-binding domains. We then focus on the functions of LecPs; LecRLKs and LecRLPs referring to the biological processes they are involved in and to the ligands they recognize. Together; LecPs; LecRLKs and LecRLPs constitute versatile recognition systems at the cell surface contributing to the detection of symbionts and pathogens; and/or involved in monitoring of the cell wall structure and cell growth.

  13. Purification, crystallization and preliminary X-ray structure analysis of the banana lectin from Musa paradisiaca.

    PubMed

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

    2004-11-01

    The banana lectin from Musa paradisiaca, MW 29.4 kDa, has been isolated, purified and crystallized. The trigonal crystals contain one dimeric molecule in the asymmetric unit. The structure has been solved using molecular replacement to a resolution of 3 A. The structure of the subunit is similar to that of jacalin-like lectins.

  14. Rapid Methods for the Laboratory Identification of Pathogenic Microorganisms.

    DTIC Science & Technology

    1981-09-01

    Preliminary results provide strong evidence to show that the fungi, Candida and Cryptococcus , can be raoidly differentiated by a lectin test. SFor Oro...SUMMATION LECTIN-YEAST INTERACTIONS Objective: To find a lectin that selectively agglutinates Cryptococcus neoformans (the etiologic agent of...peanut), Conavalia ensiformis (Con A) and mango extract may potentially be utilized to differentiate Cryptococcus from the other yeasts most commonly

  15. Selective binding and transcytosis of Ulex europaeus 1 lectin by mouse Peyer's patch M-cells in vivo.

    PubMed

    Clark, M A; Jepson, M A; Simmons, N L; Hirst, B H

    1995-12-01

    The in vivo interaction of the lectin Ulex europaeus agglutinin 1 with mouse Peyer's patch follicle-associated epithelial cells was studied in the mouse Peyer's patch gut loop model by immunofluorescence and electron microscopy. The lectin targets to mouse Peyer's patch M-cells and is rapidly endocytosed and transcytosed. These processes are accompanied by morphological changes in the M-cell microvilli and by redistribution of polymerised actin. The demonstration of selective binding and uptake of a lectin by intestinal M-cells in vivo suggests that M-cell-specific surface glycoconjugates might act as receptors for the selective adhesion/uptake of microorganisms.

  16. Parkia pendula lectin as histochemistry marker for meningothelial tumour.

    PubMed

    Beltrão, E I C; Medeiros, P L; Rodrigues, O G; Figueredo-Silva, J; Valença, M M; Coelho, L C B B; Carvalho, L B

    2003-01-01

    Lectins have been intensively used in histochemical techniques for cell surface characterization. These proteins are involved in several biological processes and their use as histochemical markers have been evaluated since they can indicate differences in cell surfaces. Parkia pendula lectin (PpeL) was evaluated as histochemical marker for meningothelial meningioma biopsies. Tissue slices were incubated with PpeL conjugated to horseradish peroxidase (PpeL-HRP) and Concanavalin A-HRP (ConA-HPR) and the binding visualized with diaminobenzidine and hydrogen peroxide. The lectin-tissue binding was inhibited with D-glucose. PpeL showed to be a useful tool for the characterization of meningothelial tumour and clinico-pathological diagnosis.

  17. A Lectin Purified from Blood Red Bracket Mushroom, Pycnoporus sanguineus (Agaricomycetidae), Mycelium Displayed Affinity Toward Bovine Transferrin.

    PubMed

    Albores, Silvana; Moros, Maria; Cerdeiras, Maria Pia; de la Fuente, Jesus Martinez; Grazu, Valeria; Fraguas, Laura Franco

    2016-01-01

    Fungal lectins constitute excellent ligands for development of affinity adsorbents useful in affinity chromatography. In this work, a lectin was purified from Pycnoporus sanguineus (PSL) mycelium using 3 procedures: by affinity chromatography, using magnetic galactosyl-nanoparticles or galactose coupled to Sepharose, and by ionic exchange chromatography (IEC). The highest lectin yield was achieved by IEC (55%); SDS-PAGE of PSL showed 2 bands with molecular mass of 68.7 and 55.2 kDa and IEC displayed 2 bands at pi 5.5 and 5.2. The lectin agglutinates rat erythrocytes, exhibiting broad specificity toward several monosaccharides, including galactose. The agglutination was also inhibited by the glycoproteins fetal calf fetuin, bovine lactoferrin, bovine transferrin, and horseradish peroxidase. The lectin was then used to synthesize an affinity adsorbent (PSL-Sepharose) and the interaction with glycoproteins was evaluated by analyzing their chromatographic behaviors. The strongest interaction with the PSL-derivative was observed with transferrin, although lower interactions were also displayed toward fetuin and lactoferrin. These results indicate that the purified PSL constitutes an interesting ligand for the design of affinity adsorbents to be used (i.e., in glycoprotein purification).

  18. Identification of Lectins from Metastatic Cancer Cells through Magnetic Glyconanoparticles

    PubMed Central

    Kavunja, Herbert W.; Voss, Patricia G.

    2016-01-01

    Cancer cells can have characteristic carbohydrate binding properties. Previously, it was shown that a highly metastatic melanoma cell line B16F10 bound to galacto-side-functionalized nanoparticles much stronger than the corresponding less metastatic B16F1 cells. To better understand the carbohydrate binding properties of cancer cells, herein, we report the isolation and characterization of endogenous galactose binding proteins from B16F10 cells using magnetic glyconanoparticles. The galactose-coated magnetic glyconanoparticles could bind with lectins present in the cells and be isolated through magnet-mediated separation. Through Western blot and mass spectrometry, the arginine/serine rich splicing factor Sfrs1 was identified as a galactose-selective endogenous lectin, overexpressed in B16F10 cells, compared with B16F1 cells. In addition, galactin-3 was found in higher amounts in B16F10 cells. Finally, the glyconanoparticles exhibited a superior efficiency in lectin isolation, from both protein mixtures and live cells, than the corresponding more traditional microparticles functionalized with carbohydrates. Thus, the magnetic glyconanoparticles present a useful tool for discovery of endogenous lectins, as well as binding partners of lectins, without prior knowledge of protein identities. PMID:27110035

  19. Oligolysine-based saccharide clusters: synthesis and specificity.

    PubMed Central

    Frison, Natacha; Marceau, Philippe; Roche, Annie-Claude; Monsigny, Michel; Mayer, Roger

    2002-01-01

    In search of specific and highly selective sugar clusters for cell receptors, such as membrane lectins, various disaccharides were coupled to small peptide cores through an amide bond. In a first step, the reducing disaccharides, i.e. lactose and three different dimannoses, were converted into glycosyl-pyroglutamyl-beta-alanine derivatives. The free carboxylic group of these conjugates was then coupled to the alpha and epsilon amino groups of the core peptide (Lys( n )-Ala-Cys-NH2) with n =1 to 5, with complete substitution leading to homogeneous glycoclusters. The thiol group of the cysteine residue was used to tag the glycosylated oligolysines upon reaction with fluorescein iodoacetamide. The affinity of these glycoclusters towards two plant lectins was assessed by surface plasmon resonance. The selectivity of their cell uptake was investigated by flow cytometry using two types of cells: a human hepatoma cell line (HepG2 cells) expressing the plasma membrane galactose-specific lectin, and monocyte-derived dendritic cells expressing the plasma membrane mannose-specific lectin. The glycoclusters containing four or five disaccharides were shown to bind plant lectins and cell surface membrane lectins with a narrow selectivity and with a high affinity. PMID:12119048

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

    PubMed Central

    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

  1. 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).

    PubMed

    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.

  2. Three novel B-type mannose-specific lectins of Cynoglossus semilaevis possess varied antibacterial activities against Gram-negative and Gram-positive bacteria.

    PubMed

    Sun, Yuan-yuan; Liu, Li; Li, Jun; Sun, Li

    2016-02-01

    Lectins are a group of sugar-binding proteins that are important factors of the innate immune system. In this study, we examined, in a comparative manner, the expression and function of three Bulb-type (B-type) mannose-specific lectins (named CsBML1, CsBML2, and CsBML3) from tongue sole. All three lectins possess three repeats of the conserved mannose binding motif QXDXNXVXY. Expression of CsBML1, CsBML2, and CsBML3 was most abundant in liver and upregulated by bacterial infection. Recombinant (r) CsBML1, CsBML2, and CsBML3 bound to a wide arrange of bacteria in a dose-dependent manner and with different affinities. All three lectins displayed mannose-specific and calcium-dependent agglutinating capacities but differed in agglutinating profiles. rCsBML1 and rCsBML2, but not rCsBML3, killed target bacteria in vitro and inhibited bacterial dissemination in fish tissues in vivo. These results indicate for the first time that in teleost, different members of B-type mannose-specific lectins likely play different roles in antibacterial immunity. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

    PubMed Central

    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

  4. Electrogenerated poly(pyrrole-lactosyl) and poly(pyrrole-3'-sialyllactosyl) interfaces: towards the impedimetric detection of lectins

    NASA Astrophysics Data System (ADS)

    Gondran, Chantal; Dubois, Marie-Pierre; Fort, Sebastien; Cosnier, Serge

    2013-07-01

    This paper reports on the impedimetric transduction of binding reaction between polymerized saccharides and target lectins. The controlled potential electro-oxidation of pyrrole-lactosyl and pyrrole-3’-sialyllactosyl at 0.95 V vs Ag/AgCl, provides thin and reproducible poly(pyrrole-saccharide) films. The affinity binding of two lectins: Arachis hypogaea, (PNA) and Maackia amurensis (MAA) onto poly(pyrrole-lactosyl) and poly(pyrrole-3’-sialyllactosyl) electrodes, was demonstrated by cyclic voltammetry in presence of ruthenium hexamine and hydroquinone. In addition, rotating disk experiments were carried out to determine the permeability of both polypyrrole films and its evolution after incubating with lectin target. Finally, the possibility of using the poly(pyrrole-lactosyl) or poly(pyrrole-3’-siallyllactosyl) films for the impedimetric transduction of the lectin binding reaction, was investigated with hydroquinone (2×10-3 mol L-1) as a redox probe in phosphate buffer. The resuting impedance spectra were interpreted and modeled as an equivalent circuit indicating that charge transfer resistance (Rct) and relaxation frequency (f°) parameters are sensitive to the lectin binding. Rct increases from 77 to 97 Ω cm2 for PNA binding and from 93 to 131 Ω cm2 for MAA binding. In parallel, f° decreases from 276 to 222 Hz for PNA binding and from 223 to 131 Hz for MAA binding. This evolution of both parameters reflects the steric hindrances generated by the immobilised lectins towards the permeation of the redox probe.

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

    PubMed

    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.

  6. New GlcNAc/GalNAc-specific lectin from the ascidian Didemnum ternatanum.

    PubMed

    Molchanova, Valentina; Chikalovets, Irina; Li, Wei; Kobelev, Stanislav; Kozyrevskaya, Svetlana; Bogdanovich, Raisa; Howard, Eric; Belogortseva, Natalia

    2005-05-25

    Previously we isolated GlcNAc-specific lectin (DTL) from the ascidian Didemnum ternatanum by affinity chromatography on cross-linked ovalbumin. Here we report the purification and characterization of new D-GlcNAc/D-GalNAc-specific lectin DTL-A from the same ascidian. This lectin was isolated from non-bound cross-linked ovalbumin fraction and further was purified by gel filtration on Sepharose CL-4B, affinity chromatography on GlcNAc-agarose and gel filtration on Superdex 200. SDS-polyacrylamide gel electrophoresis and gel filtration of purified lectin on Sepharose CL-4B indicates that it exists as large aggregates in the native state. Investigations of the carbohydrate specificity of DTL-A by enzyme-linked lectin assay suggest the multi-specificity of this lectin. DTL-A binds BSM, asialo-BSM as well as heparin and dextran sulfate. The binding of DTL-A to BSM was inhibited by monosaccharides D-GlcNAc and D-GalNAc, their alpha- but not beta-anomers. Among polysaccharides and glycoconjugates, DTL-A binding to BSM was effectively inhibited by BSM, asialo-BSM, pronase-treated BSM and synthetic alpha-D-GalNAc-PAA. Fetuin and asialofetuin showed a much lower inhibitory potency, heparin and dextran sulfate were noninhibitory. On the other hand, DTL-A binding to heparin was effectively inhibited by dextran sulfate, fucoidan, whereas BSM showed insignificantly inhibitory effect. DTL-A binding to heparin was not inhibited by D-GlcNAc and D-GalNAc.

  7. Mannose-binding lectin binds to Ebola and Marburg envelope glycoproteins, resulting in blocking of virus interaction with DC-SIGN and complement-mediated virus neutralization.

    PubMed

    Ji, Xin; Olinger, Gene G; Aris, Sheena; Chen, Ying; Gewurz, Henry; Spear, Gregory T

    2005-09-01

    Mannose-binding lectin (MBL), a serum lectin that mediates innate immune functions including activation of the lectin complement pathway, binds to carbohydrates expressed on some viral glycoproteins. In this study, the ability of MBL to bind to virus particles pseudotyped with Ebola and Marburg envelope glycoproteins was evaluated. Virus particles bearing either Ebola (Zaire strain) or Marburg (Musoke strain) envelope glycoproteins bound at significantly higher levels to immobilized MBL compared with virus particles pseudotyped with vesicular stomatitis virus glycoprotein or with no virus glycoprotein. As observed in previous studies, Ebola-pseudotyped virus bound to cells expressing the lectin DC-SIGN (dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin). However, pre-incubation of virus with MBL blocked DC-SIGN-mediated binding to cells, suggesting that the two lectins bind at the same or overlapping sites on the Ebola glycoprotein. Neutralization experiments showed that virus pseudotyped with Ebola or Marburg (Musoke) glycoprotein was neutralized by complement, while the Marburg (Ravn strain) glycoprotein-pseudotyped virus was less sensitive to neutralization. Neutralization was partially mediated through the lectin complement pathway, since a complement source deficient in MBL was significantly less effective at neutralizing viruses pseudotyped with filovirus glycoproteins and addition of purified MBL to the MBL-deficient complement increased neutralization. These experiments demonstrated that MBL binds to filovirus envelope glycoproteins resulting in important biological effects and suggest that MBL can interact with filoviruses during infection in humans.

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

    PubMed

    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.

  9. Rapid Methods for the Laboratory Identification of Pathogenic Microorganisms.

    DTIC Science & Technology

    1982-09-01

    for the use of plant proteins, called lectins, in diagnostic microbiology. We studied lectin interactions with Staphylococcus, Legionella, Streptococcus ...commercial sources (BBL and Difco). Thethree Brucella species: suis abortus, and melitensis were also purchased from BBL and Difco. Lectins were obtained...that are killed by antibiotic treatment rather than formalin. Lee Laboratories in Georgia has offered to prepare these antigens for us according to our

  10. Crystallization and preliminary characterization of a highly thermostable lectin from Trichosanthes dioica and comparison with other Trichosanthes lectins

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

    Dharkar, Poorva D.; Anuradha, P.; Gaikwad, Sushama M.

    2006-03-01

    A lectin from Trichosanthes dioica seeds has been purified and crystallized using 25%(w/v) PEG 2K MME, 0.2 M ammonium acetate, 0.1 M Tris–HCl pH 8.5 and 50 µl 0.5%(w/v) n-octyl β-d-glucopyranoside as thick needles belonging to hexagonal space group P6{sub 4}. A lectin from Trichosanthes dioica seeds has been purified and crystallized using 25%(w/v) PEG 2K MME, 0.2 M ammonium acetate, 0.1 M Tris–HCl pH 8.5 and 50 µl 0.5%(w/v) n-octyl β-d-glucopyranoside as thick needles belonging to hexagonal space group P6{sub 4}. Unit-cell parameters were a = b = 167.54, c = 77.42 Å. The crystals diffracted to a Braggmore » spacing of 2.8 Å. Both the structures of abrin-a and T. kirilowii lectin could be used as a model in structure determination using the molecular-replacement method; however, T. kirilowii lectin coordinates gave better values of reliability and correlation parameters. The thermal, chemical and pH stability of this lectin have also been studied. When heated, its haemagglutination activity remained unaffected up to 363 K. Other stability studies show that 4 M guanidinium hydrochloride (Gdn–HCl) initiates unfolding and that the protein is completely unfolded at 6 M Gdn–HCl. Treatment with urea resulted in a total loss of activity at higher concentrations of denaturant with no major structural changes. The protein remained stable over a wide pH range, from pH 6 to pH 12, except for partial unfolding at extremely alkaline pH. The role of disulfide bonds in the protein stability was found to be insignificant. Rayleigh light-scattering studies showed no molecular aggregation in any of the extreme treated conditions. The unusual stability of this lectin resembles that of type II ribosome-inactivating proteins (type II RIPs), which is also supported by structure determination. The structural features observed in a preliminary electron-density map were compared with the other two available Trichosanthes lectin structures.« less

  11. Molecular cloning, characterization and expression analysis of a putative C-type lectin (Fclectin) gene in Chinese shrimp Fenneropenaeus chinensis.

    PubMed

    Liu, Yi-Chen; Li, Fu-Hua; Dong, Bo; Wang, Bing; Luan, Wei; Zhang, Xiao-Jun; Zhang, Liu-Suo; Xiang, Jian-Hai

    2007-01-01

    Lectin is regarded as a potential molecule involved in immune recognition and phagocytosis through opsonization in crustacean. Knowledge on lectin at molecular level would help us to understand its regulation mechanism in crustacean immune system. A novel C-type lectin gene (Fclectin) was cloned from hemocytes of Chinese shrimp Fenneropenaeus chinensis by 3' and 5' rapid amplification of cDNA ends (RACE) PCR. The full-length cDNA consists of 1482 bp with an 861 bp open reading frame, encoding 287 amino acids. The deduced amino acid sequence contains a putative signal peptide of 19 amino acids. It also contains two carbohydrate recognition domains/C-type lectin-like domains (CRD1 and CRD2), which share 78% identity with each other. CRD1 and CRD2 showed 34% and 30% identity with that of mannose-binding lectin from Japanese lamprey (Lethenteron japonicum), respectively. Both CRD1 and CRD2 of Fclectin have 11 amino acids residues, which are relatively invariant in animals' C-type lectin CRDs. Five residues at Ca2+ binding site 1 are conserved in Fclectin. The potential Ca2+/carbohydrate-binding (site 2) motif QPD, E, NP (Gln-Pro-Asp, Glu, Asn-Pro) presented in the two CRDs of Fclectin may support its ability to bind galactose-type sugars. It could be deduced that Fclectin is a member of C-type lectin superfamily. Transcripts of Fclectin were found only in hemocytes by Northern blotting and RNA in situ hybridization. The variation of mRNA transcription level in hemocytes during artificial infection with bacteria and white spot syndrome virus (WSSV) was quantitated by capillary electrophoresis after RT-PCR. An exploration of mRNA expression variation after LPS stimulation was carried out in primarily cultured hemocytes in vitro. Expression profiles of Fclectin gene were greatly modified after bacteria, LPS or WSSV challenge. The above-stated data can provide us clues to understand the probable role of C-type lectin in innate immunity of shrimp and would be helpful to shrimp disease control.

  12. Symbiotic Bacteria Direct Expression of an Intestinal Bactericidal Lectin

    PubMed Central

    Cash, Heather L.; Whitham, Cecilia V.; Behrendt, Cassie L.; Hooper, Lora V.

    2009-01-01

    The mammalian intestine harbors complex societies of beneficial bacteria that are maintained in the lumen with minimal penetration of mucosal surfaces. Microbial colonization of germ-free mice triggers epithelial expression of RegIIIγ, a secreted C-type lectin. RegIIIγ binds intestinal bacteria but lacks the complement recruitment domains present in other microbe-binding mammalian C-type lectins. We show that RegIIIγ and its human counterpart, HIP/PAP, are directly antimicrobial proteins that bind their bacterial targets via interactions with peptidoglycan carbohydrate. We propose that these proteins represent an evolutionarily primitive form of lectin-mediated innate immunity, and that they reveal intestinal strategies for maintaining symbiotic host-microbial relationships. PMID:16931762

  13. The use of lectins as markers for differentiated secretory cells in planarians.

    PubMed

    Zayas, Ricardo M; Cebrià, Francesc; Guo, Tingxia; Feng, Junjie; Newmark, Phillip A

    2010-11-01

    Freshwater planarians have reemerged as excellent models to investigate mechanisms underlying regeneration. The introduction of molecular tools has facilitated the study of planarians, but cell- and tissue-specific markers are still needed to examine differentiation of most cell types. Here we report the utility of fluorescent lectin-conjugates to label tissues in the planarian Schmidtea mediterranea. We show that 16 lectin-conjugates stain planarian cells or tissues; 13 primarily label the secretory cells, their cytoplasmic projections, and terminal pores. Thus, we examined regeneration of the secretory system using lectin markers and functionally characterized two genes expressed in the secretory cells: marginal adhesive gland-1 (mag-1) and Smed-reticulocalbin1 (Smed-rcn1). RNAi knockdown of these genes caused a dramatic reduction of secretory cell lectin staining, suggesting a role for mag-1 and Smed-rcn1 in secretory cell differentiation. Our results provide new insights into planarian secretory system regeneration and add new markers for labeling several planarian tissues. © 2010 Wiley-Liss, Inc.

  14. Structural insights into Aspergillus fumigatus lectin specificity: AFL binding sites are functionally non-equivalent.

    PubMed

    Houser, Josef; Komarek, Jan; Cioci, Gianluca; Varrot, Annabelle; Imberty, Anne; Wimmerova, Michaela

    2015-03-01

    The Aspergillus fumigatus lectin AFL was recently described as a new member of the AAL lectin family. As a lectin from an opportunistic pathogen, it might play an important role in the interaction of the pathogen with the human host. A detailed study of structures of AFL complexed with several monosaccharides and oligosaccharides, including blood-group epitopes, was combined with affinity data from SPR and discussed in the context of previous findings. Its six binding sites are non-equivalent, and owing to minor differences in amino-acid composition they exhibit a marked difference in specific ligand recognition. AFL displays a high affinity in the micromolar range towards oligosaccharides which were detected in plants and also those bound on the human epithelia. All of these results indicate AFL to be a complex member of the lectin family and a challenging target for future medical research and, owing to its binding properties, a potentially useful tool in specific biotechnological applications.

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

    PubMed

    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.

  16. "Click" saccharide/beta-lactam hybrids for lectin inhibition.

    PubMed

    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.

  17. Aptamer-recognized carbohydrates on the cell membrane revealed by super-resolution microscopy.

    PubMed

    Jing, Yingying; Cai, Mingjun; Xu, Haijiao; Zhou, Lulu; Yan, Qiuyan; Gao, Jing; Wang, Hongda

    2018-04-26

    Carbohydrates are one of the most important components on the cell membrane, which participate in various physiological activities, and their aberrant expression is a consequence of pathological changes. In previous studies, carbohydrate analysis basically relied on lectins. However, discrimination between lectins still exists due to their multivalent character. Furthermore, the structures obtained by carbohydrate-lectin crosslinking confuse our direct observation to some extent. Fortunately, the emergence of aptamers, which are smaller and more flexible, has provided us an unprecedented choice. Herein, an aptamer recognition method with high precise localization was developed for imaging membrane-bound N-acetylgalactosamine (GalNAc). By using direct stochastic optical reconstruction microscopy (dSTORM), we compared this aptamer recognition method with the lectin recognition method for visualizing the detailed structure of GalNAc at the nanometer scale. The results indicated that GalNAc forms irregular clusters on the cell membrane with a resolution of 23 ± 7 nm by aptamer recognition. Additionally, when treated with N-acetylgalactosidase, the aptamer-recognized GalNAc shows a more significant decrease in cluster size and localization density, thus verifying better specificity of aptamers than lectins. Collectively, our study suggests that aptamers can act as perfect substitutes for lectins in carbohydrate labeling, which will be of great potential value in the field of super-resolution fluorescence imaging.

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

    PubMed

    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.

  19. High levels of E4-PHA-reactive oligosaccharides: potential as marker for cells with characteristics of hepatic progenitor cells.

    PubMed

    Sasaki, Nozomi; Moriwaki, Kenta; Uozumi, Naofumi; Noda, Katsuhisa; Taniguchi, Naoyuki; Kameyama, Akihiko; Narimatsu, Hisashi; Takeishi, Shunsaku; Yamada, Masao; Koyama, Nobuto; Miyoshi, Eiji

    2009-12-01

    Oligosaccharides serve as markers of the cell surface and have been used as certain kinds of tumor markers. In the present study, we established a simple method for isolating hepatic progenitor cells using a lectin, which recognizes a characteristic oligosaccharide structure. Rat liver epithelial (RLE) cells, which have been established as a hepatic stem-like cell, were used to identify characteristic oligosaccharide structures on hepatic stem cells. As a result from lectin micro array, several types of lectin including E4-PHA were identified to bind RLE cells specifically. Furthermore, lectin blot and lectin flow cytometry analyses showed that binding to E(4)-PHA lectin was significantly increased in RLE cells, compared to hepatocytes, and hepatoma cells. The induction of differentiation into a hepatocyte lineage of RLE cells by treatment with Oncostatin M and dexamethasone resulted in a decrease in E(4)-PHA binding. Using an E(4)-PHA column, we succeeded in isolating hepatic stem cells from LEC (Long-Evans with cinnamon coat color) rat livers with fluminant hepatitis. The characteristics of the established cells were similar to RLE cells and had a potential of proliferating in rat liver. These results suggest that oligosaccharides can serve as a novel marker for the isolation of the hepatic progenitor cells.

  20. Molecular cloning of a C-type lectin (LvLT) from the shrimp Litopenaeus vannamei: early gene down-regulation after WSSV infection.

    PubMed

    Ma, Tracy Hoi Tung; Tiu, Shirley Hiu Kwan; He, Jian-Guo; Chan, Siu-Ming

    2007-08-01

    C-type lectin is one of the pattern-recognition proteins of the non-self innate immune system in the invertebrates. In this study, a lectin-like cDNA (LvLT) of Litopenaeus vannamei was cloned and characterized. LvLT cDNA consists of 1035 nt encoding for a protein with 345 amino acid residues. The deduced LvLT consists of two putative carbohydrate-recognition domains (CRDs) as found in most C-type lectins. The first CRD consists of an amino acid motif (QPD) for the binding of galactose and the other CRDs consist of amino acid motifs (EPN) for the binding of mannose. Except for some conserved amino acid residues, the CRD of LvLT shared an overall low amino acid sequence identity with CRDs of other lectins. Unlike other shrimp lectins, LvLT is expressed only in the hepatopancreas but not in the hemocytes as revealed by RT-PCR. When juvenile shrimp were challenged with shrimp extracts containing white spot syndrome virus (WSSV), the expression levels of LvLT decreased initially in the first 2 h and then increased to a much higher level after 4 h. The results suggest that the initial reduction in LvLT transcript level may be related to the WSSV infection in shrimp.

  1. Preventing Pseudomonas aeruginosa and Chromobacterium violaceum infections by anti-adhesion-active components of edible seeds

    PubMed Central

    2012-01-01

    Background Pseudomonas aeruginosa adhesion to animal/human cells for infection establishment involves adhesive proteins, including its galactose- and fucose-binding lectins PA-IL (LecA) and PA-IIL (LecB). The lectin binding to the target-cell receptors may be blocked by compatible glycans that compete with those of the receptors, functioning as anti-adhesion glycodecoys. The anti-adhesion treatment is of the utmost importance for abrogating devastating antibiotic-resistant P. aeruginosa infections in immunodeficient and cystic fibrosis (CF) patients. This strategy functions in nature in protecting embryos and neonates. We have shown that PA-IL, PA-IIL, and also CV-IIL (a PA-IIL homolog produced in the related pathogen Chromobacterium violaceum) are highly useful for revealing natural glycodecoys that surround embryos in diverse avian eggs and are supplied to neonates in milks and royal jelly. In the present study, these lectins were used as probes to search for seed embryo-protecting glycodecoys. Methods The lectin-blocking glycodecoy activities were shown by the hemagglutination-inhibition test. Lectin-binding glycoproteins were detected by Western blotting with peroxidase-labeled lectins. Results The present work reports the finding - by using PA-IL, PA-IIL, and CV-IIL - of rich glycodecoy activities of low (< 10 KDa) and high MW (> 10 kDa) compounds (including glycoproteins) in extracts of cashew, cocoa, coffee, pumpkin, and tomato seeds, resembling those of avian egg whites, mammal milks, and royal jelly. Conclusions Edible seed extracts possess lectin-blocking glycodecoys that might protect their embryos from infections and also might be useful for hampering human and animal infections. PMID:22336073

  2. Binding of navy bean (Phaseolus vulgaris) lectin to the intestinal cells of the rat and its effect on the absorption of glucose

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

    Donatucci, D.A.; Liener, I.E.; Gross, C.J.

    The main objectives of this investigation were to study the binding of a lectin from navy beans with the epithelial cells of the rat intestine and to assess the effect of such binding on the ability of the intestine to absorb glucose. A Scatchard plot, based on the binding of /sup 125/I-labeled lectin to isolated intestinal epithelial cells, was used to calculate an association constant (Ka) of 15 x 10(6)M-1 and the number of binding sites per cell, 12 x 10(6). Metabolic studies were conducted over a period of 5 d on groups of rats fed raw or autoclaved navymore » bean flour and casein with or without the purified lectin. Growth, protein digestibility, biological value and net protein utilization were significantly lower in animals that had been fed raw navy bean flour or casein plus lectin than in control groups fed diets containing autoclaved navy bean flour or casein alone. Vascular perfusion was used to measure the rate of uptake of glucose by the intestines of rats that had received the various dietary treatments. The rate of absorption of (/sup 14/C)glucose by intestines from rats fed raw navy bean flour or casein plus lectin was approximately one-half that of their counterparts fed the autoclaved flour or casein alone. These results provide evidence that the lectin, by virtue of its interference with intestinal absorption, is responsible, at least in part, for the nutritional inferiority of raw navy beans.« less

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

    PubMed

    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.

  4. Identification of polymorphisms in the bovine collagenous lectins and their association with infectious diseases in cattle.

    PubMed

    Fraser, R S; Lumsden, J S; Lillie, B N

    2018-05-10

    Infectious diseases are a significant issue in animal production systems, including both the dairy and beef cattle industries. Understanding and defining the genetics of infectious disease susceptibility in cattle is an important step in the mitigation of their impact. Collagenous lectins are soluble pattern recognition receptors that form an important part of the innate immune system, which serves as the first line of host defense against pathogens. Polymorphisms in the collagenous lectin genes have been shown in previous studies to contribute to infectious disease susceptibility, and in cattle, mutations in two collagenous lectin genes (MBL1 and MBL2) are associated with mastitis. To further characterize the contribution of variation in the bovine collagenous lectins to infectious disease susceptibility, we used a pooled NGS approach to identify short nucleotide variants (SNVs) in the collagenous lectins (and regulatory DNA) of cattle with (n = 80) and without (n = 40) infectious disease. Allele frequency analysis identified 74 variants that were significantly (p < 5 × 10 -6 ) associated with infectious disease, the majority of which were clustered in a 29-kb segment upstream of the collectin locus on chromosome 28. In silico analysis of the functional effects of all the variants predicted 11 SNVs with a deleterious effect on protein structure and/or function, 148 SNVs that occurred within potential transcription factor binding sites, and 31 SNVs occurring within potential miRNA binding elements. This study provides a detailed look at the genetic variation of the bovine collagenous lectins and identifies potential genetic markers for infectious disease susceptibility.

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

    PubMed

    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.

  6. Flow cytometric analysis of lectin binding to in vitro-cultured Perkinsus marinus surface carbohydrates

    USGS Publications Warehouse

    Gauthier, J.D.; Jenkins, J.A.; La Peyre, Jerome F.

    2004-01-01

    Parasite surface glycoconjugates are frequently involved in cellular recognition and colonization of the host. This study reports on the identification of Perkinsus marinus surface carbohydrates by flow cytometric analyses of fluorescein isothiocyanate-conjugated lectin binding. Lectin-binding specificity was confirmed by sugar inhibition and Kolmogorov-Smirnov statistics. Clear, measurable fluorescence peaks were discriminated, and no parasite autofluorescence was observed. Parasites (GTLA-5 and Perkinsus-1 strains) harvested during log and stationary phases of growth in a protein-free medium reacted strongly with concanavalin A and wheat germ agglutinin, which bind to glucose-mannose and N-acetyl-D-glucosamine (GlcNAc) moieties, respectively. Both P. marinus strains bound with lower intensity to Maclura pomifera agglutinin, Bauhinia purpurea agglutinin, soybean agglutinin (N-acetyl-D-galactosamine-specific lectins), peanut agglutinin (PNA) (terminal galactose specific), and Griffonia simplicifolia II (GlcNAc specific). Only background fluorescence levels were detected with Ulex europaeus agglutinin I (L-fucose specific) and Limulus polyphemus agglutinin (sialic acid specific). The lectin-binding profiles were similar for the 2 strains except for a greater relative binding intensity of PNA for Perkinsus-1 and an overall greater lectin-binding capacity of Perkinsus-1 compared with GTLA-5. Growth stage comparisons revealed increased lectin-binding intensities during stationary phase compared with log phase of growth. This is the first report of the identification of surface glycoconjugates on a Perkinsus spp. by flow cytometry and the first to demonstrate that differential surface sugar expression is growth phase and strain dependent. ?? American Society of Parasitologists 2004.

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

    PubMed Central

    Osthoff, Michael; Brown, Karl D.; Kong, David C.M.; Daniell, Mark

    2014-01-01

    Purpose 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. Methods 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. Results 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. Conclusions 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. PMID:24426774

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

    PubMed

    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.

  9. Diagnosis of myocardial infarction based on lectin-induced erythrocyte agglutination: a feasibility study

    NASA Astrophysics Data System (ADS)

    Bocsi, József; Nieschke, Kathleen; Mittag, Anja; Reichert, Thomas; Laffers, Wiebke; Marecka, Monika; Pierzchalski, Arkadiusz; Piltz, Joachim; Esche, Hans-Jürgen; Wolf, Günther; Dähnert, Ingo; Baumgartner, Adolf; Tarnok, Attila

    2014-03-01

    Myocardial infarction (MI) is an acute life-threatening disease with a high incidence worldwide. Aim of this study was to test lectin-carbohydrate binding-induced red blood cell (RBC) agglutination as an innovative tool for fast, precise and cost effective diagnosis of MI. Five lectins (Ricinus communis agglutinin (RCA), Phaseolus vulgaris erythroagglutinin (PHA), Datura stramonium agglutinin (DSA), Artocarpus agglutinin (ArA), Triticum agglutinin (TA)) were tested for ability to differentiate between agglutination characteristics in patients with MI (n = 101) or angina pectoris without MI (AP) (n = 34) and healthy volunteers (HV) as control (n =68) . RBC agglutination was analyzed by light absorbance of a stirred RBC suspension in the green to red light spectrum in an agglutimeter (amtec, Leipzig, Germany) for 15 min after lectin addition. Mean cell count in aggregates was estimated from light absorbance by a mathematical model. Each lectin induced RBC agglutination. RCA led to the strongest RBC agglutination (~500 RBCs/aggregate), while the others induced substantially slower agglutination and lead to smaller aggregate sizes (5-150 RBCs/aggregate). For all analyzed lectins the lectin-induced RBC agglutination of MI or AP patients was generally higher than for HV. However, only PHA induced agglutination that clearly distinguished MI from HV. Variance analysis showed that aggregate size after 15 min. agglutination induced by PHA was significantly higher in the MI group (143 RBCs/ aggregate) than in the HV (29 RBC-s/aggregate, p = 0.000). We hypothesize that pathological changes during MI induce modification of the carbohydrate composition on the RBC membrane and thus modify RBC agglutination. Occurrence of carbohydrate-lectin binding sites on RBC membranes provides evidence about MI. Due to significant difference in the rate of agglutination between MI > HV the differentiation between these groups is possible based on PHA-induced RBC-agglutination. This novel assay could serve as a rapid, cost effective valuable new tool for diagnosis of MI.

  10. Computational Analysis of the Ligand Binding Site of the Extracellular ATP Receptor, DORN1

    DOE PAGES

    Nguyen, Cuong The; Tanaka, Kiwamu; Cao, Yangrong; ...

    2016-09-01

    DORN1 (also known as P2K1) is a plant receptor for extracellular ATP, which belongs to a large gene family of legume-type (L-type) lectin receptor kinases. Extracellular ATP binds to DORN1 with strong affinity through its lectin domain, and the binding triggers a variety of intracellular activities in response to biotic and abiotic stresses. However, information on the tertiary structure of the ligand binding site of DORN1is lacking, which hampers efforts to fully elucidate the mechanism of receptor action. Available data of the crystal structures from more than 50 L-type lectins enable us to perform an in silico study of molecularmore » interaction between DORN1 and ATP. In this study, we employed a computational approach to develop a tertiary structure model of the DORN1 lectin domain. A blind docking analysis demonstrated that ATP binds to a cavity made by four loops (defined as loops A B, C and D) of the DORN1 lectin domain with high affinity. In silico target docking of ATP to the DORN1 binding site predicted interaction with 12 residues, located on the four loops, via hydrogen bonds and hydrophobic interactions. The ATP binding pocket is structurally similar in location to the carbohydrate binding pocket of the canonical L-type lectins. However, four of the residues predicted to interact with ATP are not conserved between DORN1 and the other carbohydrate-binding lectins, suggesting that diversifying selection acting on these key residues may have led to the ATP binding activity of DORN1. Finally, the in silico model was validated by in vitro ATP binding assays using the purified extracellular lectin domain of wild-type DORN1, as well as mutated DORN1 lacking key ATP binding residues.« less

  11. Computational Analysis of the Ligand Binding Site of the Extracellular ATP Receptor, DORN1

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

    Nguyen, Cuong The; Tanaka, Kiwamu; Cao, Yangrong

    DORN1 (also known as P2K1) is a plant receptor for extracellular ATP, which belongs to a large gene family of legume-type (L-type) lectin receptor kinases. Extracellular ATP binds to DORN1 with strong affinity through its lectin domain, and the binding triggers a variety of intracellular activities in response to biotic and abiotic stresses. However, information on the tertiary structure of the ligand binding site of DORN1is lacking, which hampers efforts to fully elucidate the mechanism of receptor action. Available data of the crystal structures from more than 50 L-type lectins enable us to perform an in silico study of molecularmore » interaction between DORN1 and ATP. In this study, we employed a computational approach to develop a tertiary structure model of the DORN1 lectin domain. A blind docking analysis demonstrated that ATP binds to a cavity made by four loops (defined as loops A B, C and D) of the DORN1 lectin domain with high affinity. In silico target docking of ATP to the DORN1 binding site predicted interaction with 12 residues, located on the four loops, via hydrogen bonds and hydrophobic interactions. The ATP binding pocket is structurally similar in location to the carbohydrate binding pocket of the canonical L-type lectins. However, four of the residues predicted to interact with ATP are not conserved between DORN1 and the other carbohydrate-binding lectins, suggesting that diversifying selection acting on these key residues may have led to the ATP binding activity of DORN1. Finally, the in silico model was validated by in vitro ATP binding assays using the purified extracellular lectin domain of wild-type DORN1, as well as mutated DORN1 lacking key ATP binding residues.« less

  12. Visualization of melanoma tumor with lectin-conjugated rare-earth doped fluoride nanocrystals

    PubMed Central

    Dumych, Tetiana; Lutsyk, Maxym; Banski, Mateusz; Yashchenko, Antonina; Sojka, Bartlomiej; Horbay, Rostyslav; Lutsyk, Alexander; Stoika, Rostyslav; Misiewicz, Jan; Podhorodecki, Artur; Bilyy, Rostyslav

    2014-01-01

    Aim To develop specific fluorescent markers for melanoma tumor visualization, which would provide high selectivity and reversible binding pattern, by the use of carbohydrate-recognizing proteins, lectins, combined with the physical ability for imaging deep in the living tissues by utilizing red and near infrared fluorescent properties of specific rare-earth doped nanocrystals (NC). Methods B10F16 melanoma cells were inoculated to C57BL/6 mice for inducing experimental melanoma tumor. Tumors were removed and analyzed by lectin-histochemistry using LABA, PFA, PNA, HPA, SNA, GNA, and NPL lectins and stained with hematoxylin and eosin. NPL lectin was conjugated to fluorescent NaGdF4:Eu3+-COOH nanoparticles (5 nm) via zero length cross-linking reaction, and the conjugates were purified from unbound substances and then used for further visualization of histological samples. Fluorescent microscopy was used to visualize NPL-NaGdF4:Eu3+ with the fluorescent emission at 600-720 nm range. Results NPL lectin selectively recognized regions of undifferentiated melanoblasts surrounding neoangiogenic foci inside melanoma tumor, PNA lectin recognized differentiated melanoblasts, and LCA and WGA were bound to tumor stroma regions. NPL-NaGdF4:Eu3+ conjugated NC were efficiently detecting newly formed regions of melanoma tumor, confirmed by fluorescent microscopy in visible and near infrared mode. These conjugates possessed high photostability and were compatible with convenient xylene-based mounting systems and preserved intensive fluorescent signal at samples storage for at least 6 months. Conclusion NPL lectin-NaGdF4:Eu3+ conjugated NC permitted distinct identification of contours of the melanoma tissue on histological sections using red excitation at 590-610 nm and near infrared emission of 700-720 nm. These data are of potential practical significance for development of glycans-conjugated nanoparticles to be used for in vivo visualization of melanoma tumor. PMID:24891277

  13. Genome-wide analysis of lectin receptor-like kinases in Populus

    DOE PAGES

    Yang, Yongil; Labbé, Jessy; Muchero, Wellington; ...

    2016-09-01

    Receptor-like kinases (RLKs) belong to a large protein family with over 600 members in Arabidopsis and over 1000 in rice. Among RLKs, the lectin receptor-like kinases (LecRLKs) possess a characteristic extracellular carbohydrate-binding lectin domain and play important roles in plant development and innate immunity. In addition, there are 75 and 173 LecRLKs in Arabidopsis and rice, respectively. However, little is known about LecRLKs in perennial woody plants.

  14. Lectin binding profiles of SSEA-4 enriched, pluripotent human embryonic stem cell surfaces

    PubMed Central

    Venable, Alison; Mitalipova, Maisam; Lyons, Ian; Jones, Karen; Shin, Soojung; Pierce, Michael; Stice, Steven

    2005-01-01

    Background Pluripotent human embryonic stem cells (hESCs) have the potential to form every cell type in the body. These cells must be appropriately characterized prior to differentiation studies or when defining characteristics of the pluripotent state. Some developmentally regulated cell surface antigens identified by monoclonal antibodies in a variety of species and stem cell types have proven to be side chains of membrane glycolipids and glycoproteins. Therefore, to examine hESC surfaces for other potential pluripotent markers, we used a panel of 14 lectins, which were chosen based on their specificity for a variety of carbohydrates and carbohydrate linkages, along with stage specific embryonic antigen-4 (SSEA-4), to determine binding quantitation by flow cytometry and binding localization in adherent colonies by immunocytochemistry. Results Enriching cells for SSEA-4 expression increased the percentage of SSEA-4 positive cells to 98–99%. Using enriched high SSEA-4-expressing hESCs, we then analyzed the binding percentages of selected lectins and found a large variation in binding percentages ranging from 4% to 99% binding. Lycopersicon (tomato)esculetum lectin (TL), Ricinus communis agglutinin (RCA), and Concanavalin A (Con A) bound to SSEA-4 positive regions of hESCs and with similar binding percentages as SSEA-4. In contrast, we found Dolichos biflorus agglutinin (DBA) and Lotus tetragonolobus lectin (LTL) did not bind to hESCs while Phaseolus vulgaris leuco-agglutinin (PHA-L), Vicia villosa agglutinin (VVA), Ulex europaeus agglutinin (UEA), Phaseolus vulgaris erythro-agglutinin (PHA-E), and Maackia amurensis agglutinin (MAA) bound partially to hESCs. These binding percentages correlated well with immunocytochemistry results. Conclusion Our results provide information about types of carbohydrates and carbohydrate linkages found on pluripotent hESC surfaces. We propose that TL, RCA and Con A may be used as markers that are associated with the pluripotent state of hESCs because binding percentages and binding localization of these lectins are similar to those of SSEA-4. Non-binding lectins, DBA and LTL, may identify differentiated cell types; however, we did not find these lectins to bind to pluripotent SSEA-4 positive hESCs. This work represents a fundamental base to systematically classify pluripotent hESCs, and in future studies these lectins may be used to distinguish differentiated hESC types based on glycan presentation that accompanies differentiation. PMID:16033656

  15. Phylogenetic and specificity studies of two-domain GNA-related lectins: generation of multispecificity through domain duplication and divergent evolution

    PubMed Central

    Van Damme, Els J. M.; Nakamura-Tsuruta, Sachiko; Smith, David F.; Ongenaert, Maté; Winter, Harry C.; Rougé, Pierre; Goldstein, Irwin J.; Mo, Hanqing; Kominami, Junko; Culerrier, Raphaël; Barre, Annick; Hirabayashi, Jun; Peumans, Willy J.

    2007-01-01

    A re-investigation of the occurrence and taxonomic distribution of proteins built up of protomers consisting of two tandem arrayed domains equivalent to the GNA [Galanthus nivalis (snowdrop) agglutinin] revealed that these are widespread among monotyledonous plants. Phylogenetic analysis of the available sequences indicated that these proteins do not represent a monophylogenetic group but most probably result from multiple independent domain duplication/in tandem insertion events. To corroborate the relationship between inter-domain sequence divergence and the widening of specificity range, a detailed comparative analysis was made of the sequences and specificity of a set of two-domain GNA-related lectins. Glycan microarray analyses, frontal affinity chromatography and surface plasmon resonance measurements demonstrated that the two-domain GNA-related lectins acquired a marked diversity in carbohydrate-binding specificity that strikingly contrasts the canonical exclusive specificity of their single domain counterparts towards mannose. Moreover, it appears that most two-domain GNA-related lectins interact with both high mannose and complex N-glycans and that this dual specificity relies on the simultaneous presence of at least two different independently acting binding sites. The combined phylogenetic, specificity and structural data strongly suggest that plants used domain duplication followed by divergent evolution as a mechanism to generate multispecific lectins from a single mannose-binding domain. Taking into account that the shift in specificity of some binding sites from high mannose to complex type N-glycans implies that the two-domain GNA-related lectins are primarily directed against typical animal glycans, it is tempting to speculate that plants developed two-domain GNA-related lectins for defence purposes. PMID:17288538

  16. Profile of Resistance of Human Immunodeficiency Virus to Mannose-Specific Plant Lectins

    PubMed Central

    Balzarini, Jan; Van Laethem, Kristel; Hatse, Sigrid; Vermeire, Kurt; De Clercq, Erik; Peumans, Willy; Van Damme, Els; Vandamme, Anne-Mieke; Böhlmstedt, Anders; Schols, Dominique

    2004-01-01

    The mannose-specific plant lectins from the Amaryllidaceae family (e.g., Hippeastrum sp. hybrid and Galanthus nivalis) inhibit human immunodeficiency virus (HIV) infection of human lymphocytic cells in the higher nanogram per milliliter range and suppress syncytium formation between persistently HIV type 1 (HIV-1)-infected cells and uninfected CD4+ T cells. These lectins inhibit virus entry. When exposed to escalating concentrations of G. nivalis and Hippeastrum sp. hybrid agglutinin, a variety of HIV-1(IIIB) strains were isolated after 20 to 40 subcultivations which showed a decreased sensitivity to the plant lectins. Several amino acid changes in the envelope glycoprotein gp120, but not in gp41, of the mutant virus isolates were observed. The vast majority of the amino acid changes occurred at the N glycosylation sites and at the S or T residues that are part of the N glycosylation motif. The degree of resistance to the plant lectins was invariably correlated with an increasing number of mutated glycosylation sites in gp120. The nature of these mutations was entirely different from that of mutations that are known to appear in HIV-1 gp120 under the pressure of other viral entry inhibitors such as dextran sulfate, bicyclams (i.e., AMD3100), and chicoric acid, which also explains the lack of cross-resistance of plant lectin-resistant viruses to any other HIV inhibitor including T-20 and the blue-green algae (cyanobacteria)-derived mannose-specific cyanovirin. The plant lectins represent a well-defined class of anti-HIV (microbicidal) drugs with a novel HIV drug resistance profile different from those of other existing anti-HIV drugs. PMID:15367629

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

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

    Moreno, Frederico Bruno Mendes Batista; Bezerra, Gustavo Arruda; Oliveira, Taianá Maia de

    2006-11-01

    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{sub 2} and those with Man(α1-2)Man(α1)OMe crystallized in space group I222], which differed from those of the native proteins (P2{sub 1}2{sub 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 andmore » 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{sub 2} and those with Man(α1-2)Man(α1)OMe crystallized in space group I222], which differed from those of the native proteins (P2{sub 1}2{sub 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.« less

  18. Proximity labeling of cis-ligands of CD22/Siglec-2 reveals stepwise α2,6 sialic acid-dependent and -independent interactions.

    PubMed

    Alborzian Deh Sheikh, Amin; Akatsu, Chizuru; Imamura, Akihiro; Abdu-Allah, Hajjaj H M; Takematsu, Hiromu; Ando, Hiromune; Ishida, Hideharu; Tsubata, Takeshi

    2018-01-01

    Lectins expressed on the cell surface are often bound and regulated by the membrane molecules containing the glycan ligands on the same cell (cis-ligands). However, molecular nature and function of cis-ligands are generally poorly understood partly because of weak interaction between lectins and glycan ligands. Cis-ligands are most extensively studied in CD22 (also known as Siglec-2), an inhibitory B lymphocyte receptor specifically recognizing α2,6 sialic acids. CD22, CD45 and IgM are suggested to be ligands of CD22. Here we labeled molecules in the proximity of CD22 in situ on B cell surface using biotin-tyramide. Molecules including CD22, CD45 and IgM were labeled in wild-type but not ST6GalI -/- B cells that lack α2,6 sialic acids, indicating that these molecules associate with CD22 by lectin-glycan interaction, and are therefore cis-ligands. In ST6GalI -/- B cells, these cis-ligands are located in a slightly more distance from CD22. Thus, the lectin-glycan interaction recruits cis-ligands already located in the relative proximity of CD22 through non-lectin-glycan interaction to the close proximity. Moreover, cis-ligands are labeled in Cmah -/- B cells that lack Neu5Gc preferred by mouse CD22 as efficiently as in wild-type B cells, indicating that very low affinity lectin-glycan interaction is sufficient for recruiting cis-ligands, and can be detected by proximity labeling. Thus, proximity labeling with tyramide appears to be a useful method to identify cis-ligands and to analyze their interaction with the lectins. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Expression of C-type lectin receptor mRNA in chronic otitis media with cholesteatoma.

    PubMed

    Kim, Sang Hoon; Han, Seung-Ho; Byun, Jae Yong; Park, Moon Suh; Kim, Young Il; Yeo, Seung Geun

    2017-06-01

    The levels of expression of various C-type lectin receptors (CLRs) messenger ribo nucleic acids (mRNAs) were significantly higher in cholesteatomas than in normal skin, suggesting that these CLRs may be involved in the pathogenesis of cholesteatoma. Altered expression of pattern recognition receptors may be associated with immune responses in patients with cholesteatoma. This study assessed the levels of expression of CLR mRNAs in normal skin and in cholesteatoma. Cholesteatoma specimens were obtained from 38 patients with acquired cholesteatoma. The levels of expression of various CLR mRNAs were assessed quantitatively using real-time RT-PCR (Reverse transcription polymerase chain reaction) and correlated with age, sex, the presence of bacteria, hearing level, frequency of surgery, and degree of ossicle destruction. The levels of CD206 (cluster of differentiation 206), DEC-205 (Dendritic and epithelial cell-205), MGL (monoacylglycerol lipase), CLEC5A (C-type lectin domain family 5 member A), Dectin-2 (dendrite cell-associated C-type lectin-2), BDCA2 (Blood dendritic cell antigen 2), Mincle, DCIR (dendritic cell immunoreceptor), Dectin-1, MICL (Myeloid inhibitory C type-like lectin), and CLEC12B (C-type lectin domain family 12, member B) mRNAs were significantly higher in cholesteatoma than in control skin samples (p < 0.05). The levels of CLEC5A (C-type lectin domain family 5 member) and Dectin-1 mRNAs were significantly higher in cholesteatomas with ≥2 than ≤1 destroyed ossicles (p < 0.05), and the levels of MGL, Mincle, Dectin-1, and CLEC12B mRNAs were significantly higher in recurrent than initial cholesteatoma specimens (p < 0.05). The level of CLEC5A mRNAs was significantly higher in patients with severe than mild-to-moderate hearing loss (p < 0.05).

  20. Glycome Diagnosis of Human Induced Pluripotent Stem Cells Using Lectin Microarray*

    PubMed Central

    Tateno, Hiroaki; Toyota, Masashi; Saito, Shigeru; Onuma, Yasuko; Ito, Yuzuru; Hiemori, Keiko; Fukumura, Mihoko; Matsushima, Asako; Nakanishi, Mio; Ohnuma, Kiyoshi; Akutsu, Hidenori; Umezawa, Akihiro; Horimoto, Katsuhisa; Hirabayashi, Jun; Asashima, Makoto

    2011-01-01

    Induced pluripotent stem cells (iPSCs) can now be produced from various somatic cell (SC) lines by ectopic expression of the four transcription factors. Although the procedure has been demonstrated to induce global change in gene and microRNA expressions and even epigenetic modification, it remains largely unknown how this transcription factor-induced reprogramming affects the total glycan repertoire expressed on the cells. Here we performed a comprehensive glycan analysis using 114 types of human iPSCs generated from five different SCs and compared their glycomes with those of human embryonic stem cells (ESCs; nine cell types) using a high density lectin microarray. In unsupervised cluster analysis of the results obtained by lectin microarray, both undifferentiated iPSCs and ESCs were clustered as one large group. However, they were clearly separated from the group of differentiated SCs, whereas all of the four SCs had apparently distinct glycome profiles from one another, demonstrating that SCs with originally distinct glycan profiles have acquired those similar to ESCs upon induction of pluripotency. Thirty-eight lectins discriminating between SCs and iPSCs/ESCs were statistically selected, and characteristic features of the pluripotent state were then obtained at the level of the cellular glycome. The expression profiles of relevant glycosyltransferase genes agreed well with the results obtained by lectin microarray. Among the 38 lectins, rBC2LCN was found to detect only undifferentiated iPSCs/ESCs and not differentiated SCs. Hence, the high density lectin microarray has proved to be valid for not only comprehensive analysis of glycans but also diagnosis of stem cells under the concept of the cellular glycome. PMID:21471226

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

    PubMed

    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.

  2. The β-Prism Lectin Domain of Vibrio cholerae Hemolysin Promotes Self-assembly of the β-Pore-forming Toxin by a Carbohydrate-independent Mechanism*

    PubMed Central

    Ganguly, Sreerupa; Mukherjee, Amarshi; Mazumdar, Budhaditya; Ghosh, Amar N.; Banerjee, Kalyan K.

    2014-01-01

    Vibrio cholerae cytolysin/hemolysin (VCC) is an amphipathic 65-kDa β-pore-forming toxin with a C-terminal β-prism lectin domain. Because deletion or point mutation of the lectin domain seriously compromises hemolytic activity, it is thought that carbohydrate-dependent interactions play a critical role in membrane targeting of VCC. To delineate the contributions of the cytolysin and lectin domains in pore formation, we used wild-type VCC, 50-kDa VCC (VCC50) without the lectin domain, and mutant VCCD617A with no carbohydrate-binding activity. VCC and its two variants with no carbohydrate-binding activity moved to the erythrocyte stroma with apparent association constants on the order of 107 m−1. However, loss of the lectin domain severely reduced the efficiency of self-association of the VCC monomer with the β-barrel heptamer in the synthetic lipid bilayer from ∼83 to 27%. Notably, inactivation of the carbohydrate-binding activity by the D617A mutation marginally reduced oligomerization to ∼77%. Oligomerization of VCC50 was temperature-insensitive; by contrast, VCC self-assembly increased with increasing temperature, suggesting that the process is driven by entropy and opposed by enthalpy. Asialofetuin, the β1-galactosyl-terminated glycoprotein inhibitor of VCC-induced hemolysis, promoted oligomerization of 65-kDa VCC to a species that resembled the membrane-inserted heptamer in stoichiometry and morphology but had reduced global amphipathicity. In conclusion, we propose (i) that the β-prism lectin domain facilitated toxin assembly by producing entropy during relocation in the heptamer and (ii) that glycoconjugates inhibited VCC by promoting its assembly to a water-soluble, less amphipathic oligomer variant with reduced ability to penetrate the bilayer. PMID:24356964

  3. A label-free fluorescence biosensor for highly sensitive detection of lectin based on carboxymethyl chitosan-quantum dots and gold nanoparticles.

    PubMed

    Liu, Ziping; Liu, Hua; Wang, Lei; Su, Xingguang

    2016-08-17

    In this work, we report a novel label-free fluorescence "turn off-on" biosensor for lectin detection. The highly sensitive and selective sensing system is based on the integration of carboxymethyl chitosan (CM-CHIT), CuInS2 quantum dots (QDs) and Au nanoparticles (NPs). Firstly, CuInS2 QDs featuring carboxyl groups were directly synthesized via a hydrothermal synthesis method. Then, the carboxyl groups on the CuInS2 QDs surface were interacted with the amino groups (NH2), carboxyl groups (COOH) and hydroxyl groups (OH) within CM-CHIT polymeric chains via electrostatic interactions and hydrogen bonding to form CM-CHIT-QDs assemblies. Introduction of Au NPs could quench the fluorescence of CM-CHIT-QDs through electron and energy transfer. In the presence of lectin, lectin could bind exclusively with CM-CHIT-QDs by means of specific multivalent carbohydrate-protein interaction. Thus, the electron and energy transfer process between CM-CHIT-QDs and Au NPs was inhibited, and as a result, the fluorescence of CM-CHIT-QDs was effectively "turned on". Under the optimum conditions, there was a good linear relationship between the fluorescence intensity ratio I/I0 (I and I0 were the fluorescence intensity of CM-CHIT-QDs-Au NPs in the presence and absence of lectin, respectively) and lectin concentration in the range of 0.2-192.5 nmol L(-1), And the detection limit could be down to 0.08 nmol L(-1). Furthermore, the proposed biosensor was employed for the determination of lectin in fetal bovine serum samples with satisfactory results. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Differential staining of Western blots of human secreted glycoproteins from serum, milk, saliva, and seminal fluid using lectins displaying diverse sugar specificities.

    PubMed

    Gilboa-Garber, Nechama; Lerrer, Batya; Lesman-Movshovich, Efrat; Dgani, Orly

    2005-12-01

    Human milk, serum, saliva, and seminal fluid glycoproteins (gps) nourish and protect newborn and adult tissues. Their saccharides, which resemble cell membrane components, may block pathogen adhesion and infection. In the present study, they were examined by a battery of lectins from plants, animals, and bacteria, using hemagglutination inhibition and Western blot analyses. The lectins included galactophilic ones from Aplysia gonad, Erythrina corallodendron, Maclura pomifera (MPL), peanut, and Pseudomonas aeruginosa (PA-IL); fucose-binding lectins from Pseudomonas aeruginosa (PA-IIL), Ralstonia solanacearum (RSL), and Ulex europaeus (UEA-I), and mannose/glucose-binding Con A. The results demonstrated the chosen lectin efficiency for differential analysis of human secreted gps as compared to CBB staining. They unveiled the diversity of these body fluid gp glycans (those of the milk and seminal fluid being highest): the milk gps interacted most strongly with PA-IIL, followed by RSL; the saliva gps with RSL, followed by PA-IIL and MPL; the serum gps with Con A and MPL, followed by PA-IIL and RSL, and the seminal plasma gps with RSL and MPL, followed by UEA-I and PA-IIL. The potential usage of these lectins as probes for scientific, industrial, and medical purposes, and for quality control of the desired gps is clearly indicated.

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

    PubMed

    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.

  6. Isolation and Characterization of a Sex-Specific Lectin in a Marine Red Alga, Aglaothamnion oosumiense Itono

    PubMed Central

    Han, Jong Won; Klochkova, Tatyana A.; Shim, Jun Bo; Yoon, Kangsup

    2012-01-01

    In red algae, spermatial binding to female trichogynes is mediated by a lectin-carbohydrate complementary system. Aglaothamnion oosumiense is a microscopic filamentous red alga. The gamete recognition and binding occur at the surface of the hairlike trichogyne on the female carpogonium. Male spermatia are nonmotile. Previous studies suggested the presence of a lectin responsible for gamete recognition on the surface of female trychogynes. A novel N-acetyl-d-galactosamine-specific protein was isolated from female plants of A. oosumiense by affinity chromatography and named AOL1. The lectin was monomeric and did not agglutinate horse blood or human erythrocytes. The N-terminal amino acid sequence of the protein was analyzed, and degenerate primers were designed. A full-length cDNA encoding the lectin was obtained using rapid amplification of cDNA ends-PCR (RACE-PCR). The cDNA was 1,095 bp in length and coded for a protein of 259 amino acids with a deduced molecular mass of 21.4 kDa, which agreed well with the protein data. PCR analysis using genomic DNA showed that both male and female plants have this gene. However, Northern blotting and two-dimensional electrophoresis showed that this protein was expressed 12 to 15 times more in female plants. The lectin inhibited spermatial binding to the trichogynes when preincubated with spermatia, suggesting its involvement in gamete binding. PMID:22865077

  7. Technical Report for DE-FG02-03ER46029 Sugar-Coated PPEs, Novel Nanomaterials and Sensing Modules for Disease and Bioterrorism Related Threats

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

    Uwe Bunz

    2003-08-27

    The detection and sensing of biological warfare agents (Ricin, Anthrax toxin), of disease agents (cholera, botulinum and tetanus toxins, influenza virus etc) and of biologically active species is important for national security and disease control. A premiere goal would be the simple colorimetric or fluorimetric detection of such toxins by a dipstick test. It would be desirable to sense 5,000-10,000 toxin molecules, i.e. 10-100 fg of a toxin contained 1-5 mL of sample. Fluorescent conjugated polymers should be particularly interesting in this regard, because they can carry multiple identical and/or different recognition units. Such an approach is particularly valuable formore » the detection of lectin toxins, because these bind to oligomeric carbohydrate displays. Lectins bind multivalently to sugars, i.e. several covalently connected sugar moieties have to be exposed to the lectin at the same time to obtain binding. The requirement of multivalency of the lectin-sugar interactions should allow a very sensitive detection of lectins with sugar coated conjugated polymers in an agglutination type assay, where the fluorescence of the PPEs disappears upon binding to the lectins. High molecular weights of the used PPEs would mean high sensitivity. Herein we present our progress towards that goal up to date.« less

  8. Isolation and determination of the primary structure of a lectin protein from the serum of the American alligator (Alligator mississippiensis).

    PubMed

    Darville, Lancia N F; Merchant, Mark E; Maccha, Venkata; Siddavarapu, Vivekananda Reddy; Hasan, Azeem; Murray, Kermit K

    2012-02-01

    Mass spectrometry in conjunction with de novo sequencing was used to determine the amino acid sequence of a 35kDa lectin protein isolated from the serum of the American alligator that exhibits binding to mannose. The protein N-terminal sequence was determined using Edman degradation and enzymatic digestion with different proteases was used to generate peptide fragments for analysis by liquid chromatography tandem mass spectrometry (LC MS/MS). Separate analysis of the protein digests with multiple enzymes enhanced the protein sequence coverage. De novo sequencing was accomplished using MASCOT Distiller and PEAKS software and the sequences were searched against the NCBI database using MASCOT and BLAST to identify homologous peptides. MS analysis of the intact protein indicated that it is present primarily as monomer and dimer in vitro. The isolated 35kDa protein was ~98% sequenced and found to have 313 amino acids and nine cysteine residues and was identified as an alligator lectin. The alligator lectin sequence was aligned with other lectin sequences using DIALIGN and ClustalW software and was found to exhibit 58% and 59% similarity to both human and mouse intelectin-1. The alligator lectin exhibited strong binding affinities toward mannan and mannose as compared to other tested carbohydrates. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. The Tn Antigen-Specific Lectin from Ground Ivy Is an Insecticidal Protein with an Unusual Physiology1

    PubMed Central

    Wang, Weifang; Hause, Bettina; Peumans, Willy J.; Smagghe, Guy; Mackie, Anne; Fraser, Robin; Van Damme, Els J.M.

    2003-01-01

    Leaves of ground ivy (Glechoma hederacea) contain a lectin (called Gleheda) that is structurally and evolutionary related to the classical legume lectins. Screening of a population of wild plants revealed that Gleheda accounts for more than one-third of the total leaf protein in some clones, whereas it cannot be detected in other clones growing in the same environment. Gleheda is predominantly expressed in the leaves where it accumulates during early leaf maturation. The lectin is not uniformly distributed over the leaves but exhibits a unique localization pattern characterized by an almost exclusive confinement to a single layer of palisade parenchyma cells. Insect feeding trials demonstrated that Gleheda is a potent insecticidal protein for larvae of the Colorado potato beetle (Leptinotarsa decemlineata). Because Gleheda is not cytotoxic, it is suggested that the insecticidal activity is linked to the carbohydrate-binding specificity of the lectin, which as could be demonstrated by agglutination assays with different types of polyagglutinable human erythrocytes is specifically directed against the Tn antigen structure (N-acetylgalactosamine O-linked to serine or threonine residues of proteins). PMID:12857814

  10. Dynamic interplay between catalytic and lectin domains of GalNAc-transferases modulates protein O-glycosylation

    NASA Astrophysics Data System (ADS)

    Lira-Navarrete, Erandi; de Las Rivas, Matilde; Compañón, Ismael; Pallarés, María Carmen; Kong, Yun; Iglesias-Fernández, Javier; Bernardes, Gonçalo J. L.; Peregrina, Jesús M.; Rovira, Carme; Bernadó, Pau; Bruscolini, Pierpaolo; Clausen, Henrik; Lostao, Anabel; Corzana, Francisco; Hurtado-Guerrero, Ramon

    2015-05-01

    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 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 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 and relies on a flexible linker located between the catalytic and the lectin domains. Our results also shed light on how GalNAc-Ts generate dense decoration of proteins with O-glycans.

  11. Linear Precision Glycomacromolecules with Varying Interligand Spacing and Linker Functionalities Binding to Concanavalin A and the Bacterial Lectin FimH.

    PubMed

    Igde, Sinaida; Röblitz, Susanna; Müller, Anne; Kolbe, Katharina; Boden, Sophia; Fessele, Claudia; Lindhorst, Thisbe K; Weber, Marcus; Hartmann, Laura

    2017-12-01

    A series of precision glycomacromolecules is prepared following previously established solid phase synthesis allowing for controlled variations of interligand spacing and the overall number of carbohydrate ligands. In addition, now also different linkers are installed between the carbohydrate ligand and the macromolecular scaffold. The lectin binding behavior of these glycomacromolecules is then evaluated in isothermal titration calorimetry (ITC) and kinITC experiments using the lectin Concanavalin A (Con A) in its dimeric and tetrameric form. The results indicate that both sterical and statistical effects impact lectin binding of precision glycomacromolecules. Moreover, ITC results show that highest affinity toward Con A can be achieved with an ethyl phenyl linker, which parallels earlier findings with the bacterial lectin FimH. In this way, a first set of glycomacromolecule structures is selected for testing in a bacterial adhesion-inhibition study. Here, the findings point to a one-sugar binding mode mainly affected by sterical restraints of the nonbinding parts of the respective glycomacromolecule. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Synthesis of β-galactosylamides as ligands of the peanut lectin. Insights into the recognition process.

    PubMed

    Cano, María Emilia; Varela, Oscar; García-Moreno, María Isabel; García Fernández, José Manuel; Kovensky, José; Uhrig, María Laura

    2017-04-18

    The synthesis of mono and divalent β-galactosylamides linked to a hydroxylated chain having a C2 symmetry axis derived from l-tartaric anhydride is reported. Reference compounds devoid of hydroxyl groups in the linker were also prepared from β-galactosylamine and succinic anhydride. After functionalization with an alkynyl residue, the resulting building blocks were grafted onto different azide-equipped scaffolds through the copper catalyzed azide-alkyne cycloaddition. Thus, a family of structurally related mono and divalent β-N-galactopyranosylamides was obtained and fully characterized. The binding affinities of the ligands towards the model lectin PNA were measured by the enzyme-linked lectin assay (ELLA). The IC 50 values were significantly higher than that of galactose but the presence of hydroxyl groups in the aglycone chain improved lectin recognition. Docking and molecular dynamics experiments were in accordance with the hypothesis that a hydroxyl group properly disposed in the linker could mimic the Glc O3 in the recognition process. On the other hand, divalent presentation of the ligands led to lectin affinity enhancements. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Unfolding energetics and stability of banana lectin.

    PubMed

    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.

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

    PubMed Central

    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

  15. Determination of a Unique Epitope Binding Site for a Complement-Lysis- Enhancing Monoclonal Antibody, 3D12, on the Galactose Adherence Lectin of Entamoeba histolytica, Using BIAcore.

    DTIC Science & Technology

    1992-05-01

    COMPLEMENT-LYSIS-ENHANCING MONOCLONAL ANTIBODY, 3D12, ON THE GALACTOSE ADHERENCE LECTIN OF ENTAMOEBA HISTOLYTICA, USING BIAcore Sheila J. Wood...Binding 5. FUNDING NUMBERS Site for a Complement-Lysis-Enhancing Monoclonal Antibody, 3D12, on the Galactose Adherence Lectin of Entamoeba Hiiutolitica...Mechani sms of pathogenicity used by Entamoeba histolytica to invade the bloodstream and cause liver abscess, include complement mediated lysis

  16. Tumor Suppression and Sensitization to Taxol Induces Apoptosis of EIA in Breast Cancer Cells

    DTIC Science & Technology

    2005-06-01

    participated in the regulation of apoptosis induced by ceramide, mistletoe lectin, and 4-hydroxynonenal, an aldehyde product of mem- brane lipid peroxidation... Mistletoe lectin induces apoptosis and telomerase inhibition in hu- man A253 cancer cells through dephosphorylation of Akt. Arch Pharm Res 2004; 27:68-76...participated subunit of protein phosphatase 2A [PP2A (PP2A/C)l enhanced the activity in the regulation of apoptosis induced by ceramide, mistletoe lectin, of

  17. Identification of the glycoproteins of lymphocystis disease virus (LDV) of fish.

    PubMed

    Robin, J; Laperrière, A; Berthiaume, L

    1986-01-01

    Analysis of highly purified fish Lymphocystis Disease Virus (LDV), strain Leetown NFH, by three different methods, namely periodic Acid Schiff reaction, radiolabelling with tritiated fucose and N-acetyl-D-glucosamine and staining with three lectins, indicated that ten glycoproteins were associated with the virus structure. Six of them were detected by all of the three methods, three by both radiolabelling and lectin staining but only one by the lectin technique. Localization of these glycoproteins at the surface or inside the virion is discussed.

  18. A tuber lectin from Arisaema jacquemontii Blume with anti-insect and anti-proliferative properties.

    PubMed

    Kaur, Manpreet; Singh, Kuljinder; Rup, Pushpinder Jai; Kamboj, Sukhdev Singh; Saxena, Ajit Kumar; Sharma, Madhunika; Bhagat, Madhulika; Sood, Sarvesh Kumar; Singh, Jatinder

    2006-07-31

    A tuber lectin from Arisaema jacquemontii Blume belonging to family Araceae was purified by employing a single step affinity chromatography using column of asialofetuin-linked amino activated silica beads and the bound lectin was eluted with 100 mM glycine-HCl buffer pH 2.5. The purified A. jacquemontii lectin (AJL) showed a single protein band with an apparent molecular mass of 13.4 kDa when submitted to SDS-polyacrylamide gel electrophoresis under reducing as well as non-reducing conditions. The native molecular mass of AJL determined by gel filtration on a Biogel P-200 column was 52 kDa and its carbohydrate content was estimated to be 3.40%. Thus AJL is a tetrameric glycoprotein. The purified lectin agglutinated erythrocytes from rabbit but not from human. Its activity was not inhibited by any of the mono- and disaccharides tested except N-acetyl-D-lactosamine having minimal inhibitory sugar concentration (MIC) 25 mM. Among the glycoproteins tested only asialofetuin was found to be inhibitory (MIC125 microg/mL). A single band was obtained in native PAGE at pH 4.5 while PAGE at pH 8.3 showed two bands. Isoelectric focusing of AJL gave multiple bands in the pI range of 4.6-5.5. When incorporated in artificial diet AJL significantly affected the development of Bactrocera cucurbitae (Coquillett) larvae indicating the possibility of using this lectin in a biotechnological strategy for insect management of cucurbits. Larvae fed on artificial diet containing sublethal dose of AJL showed a significant decrease in acid phosphatase and alkaline phosphatase activity while esterase activity markedly increased as compared to larvae fed on diet without lectin. Out of various human cancer cell lines employed in sulphorhodamine B (SRB) assay, this lectin was found to have appreciable inhibitory effect on the in vitro proliferation of HCT-15, HOP-62, SW-620, HT-29, IMR-32, SKOV-3, Colo-205, PC-3, HEP-2 and A-549 cancer cell lines by 82, 77, 73, 70, 41, 41, 37, 29, 21 and 21% respectively.

  19. Structural analysis and unique molecular recognition properties of a Bauhinia forficata lectin that inhibits cancer cell growth.

    PubMed

    Lubkowski, Jacek; Durbin, Sarah V; Silva, Mariana C C; Farnsworth, David; Gildersleeve, Jeffrey C; Oliva, Maria Luiza V; Wlodawer, Alexander

    2017-02-01

    Lectins have been used at length for basic research and clinical applications. New insights into the molecular recognition properties enhance our basic understanding of carbohydrate-protein interactions and aid in the design/development of new lectins. In this study, we used a combination of cell-based assays, glycan microarrays, and X-ray crystallography to evaluate the structure and function of the recombinant Bauhinia forficata lectin (BfL). The lectin was shown to be cytostatic for several cancer cell lines included in the NCI-60 panel; in particular, it inhibited growth of melanoma cancer cells (LOX IMVI) by over 95%. BfL is dimeric in solution and highly specific for binding of oligosaccharides and glycopeptides with terminal N-acetylgalactosamine (GalNAc). BfL was found to have especially strong binding (apparent K d  = 0.5-1.0 nm) to the tumor-associated Tn antigen. High-resolution crystal structures were determined for the ligand-free lectin, as well as for its complexes with three Tn glycopeptides, globotetraose, and the blood group A antigen. Extensive analysis of the eight crystal structures and comparison to structures of related lectins revealed several unique features of GalNAc recognition. Of special note, the carboxylate group of Glu126, lining the glycan-binding pocket, forms H-bonds with both the N-acetyl of GalNAc and the peptide amido group of Tn antigens. Stabilization provided by Glu126 is described here for the first time for any GalNAc-specific lectin. Taken together, the results provide new insights into the molecular recognition of carbohydrates and provide a structural understanding that will enable rational engineering of BfL for a variety of applications. Structural data are available in the PDB under the accession numbers 5T50, 5T52, 5T55, 5T54, 5T5L, 5T5J, 5T5P, and 5T5O. © 2016 Federation of European Biochemical Societies.

  20. Association of Lectin Pathway Protein Levels and Genetic Variants Early after Injury with Outcomes after Severe Traumatic Brain Injury: A Prospective Cohort Study.

    PubMed

    Osthoff, Michael; Walder, Bernhard; Delhumeau, Cécile; Trendelenburg, Marten; Turck, Natacha

    2017-09-01

    The lectin pathway of the complement system has been implicated in secondary ischemic/inflammatory injury after traumatic brain injury (TBI). However, previous experimental studies have yielded conflicting results, and human studies are scarce. In this exploratory study, we investigated associations of several lectin pathway proteins early after injury and single-nucleotide polymorphisms (SNP) with outcomes after severe TBI (mortality at 14 days [primary outcome] and consciousness assessed with the Glasgow Coma Scale [GCS] at 14 days, disability assessed with the Glasgow Outcome Scale Extended [GOSE] at 90 days). Forty-four patients with severe TBI were included. Plasma levels of lectin pathway proteins were sampled at 6, 12, 24, and 48 h after injury and eight mannose-binding lectin (MBL) and ficolin (FCN)2 SNPs were analyzed by enzyme-linked immunosorbent assay (ELISA) and genotyping, respectively. Plasma protein levels were stable with only a slight increase in mannose-binding protein-associated serine protease (MASP)-2 and FCN2 levels after 48 h (p < 0.05), respectively. Neither lectin protein plasma levels (6 h or mean levels) nor MBL2 genotypes or FCN2 variant alleles were associated with 14 day mortality or 14 day consciousness. However, FCN2, FCN3, and MASP-2 levels were higher in patients with an unfavorable outcome (GOSE 1-4) at 90 days (p < 0.05), whereas there was no difference in MBL2 genotypes or FCN2 variant alleles. In particular, higher mean MASP-2 levels over 48 h were independently associated with a GOSE score < 4 at 90 days after adjustment (odds ratio 3.46 [95% confidence interval 1.12-10.68] per 100 ng/mL increase, p = 0.03). No association was observed between the lectin pathway of the complement system and 14 day mortality or 14 day consciousness. However, higher plasma FCN2, FCN3, and, in particular, MASP-2 levels early after injury were associated with an unfavorable outcome at 90 days (death, vegetative state, and severe disability) which may be related to an increased activation of the lectin pathway.

  1. Genetics Home Reference: mannose-binding lectin deficiency

    MedlinePlus

    ... Nobelprize.org: The Immune System - In More Detail Patient Support and Advocacy Resources (1 link) ... Sources for This Page Arora M, Munoz E, Tenner AJ. Identification of a site on mannan-binding lectin critical ...

  2. Crystallization and preliminary X-ray diffraction analysis of the lectin from Dioclea rostrata Benth seeds

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

    Delatorre, Plínio; Departamento de Ciências Biológicas, Universidade Regional do Cariri, Crato, CE 63195-000; Nascimento, Kyria Santiago

    2006-02-01

    D. rostrata lectin was crystallized by hanging-drop vapor diffusion. The crystal belongs to the orthorhombic space group I222 and diffracted to 1.87 Å resolution. Lectins from the Diocleinae subtribe (Leguminosae) are highly similar proteins that promote various biological activities with distinctly differing potencies. The structural basis for this experimental data is not yet fully understood. Dioclea rostrata lectin was purified and crystallized by hanging-drop vapour diffusion at 293 K. The crystal belongs to the orthorhombic space group I222, with unit-cell parameters a = 61.51, b = 88.22, c = 87.76 Å. Assuming the presence of one monomer per asymmetric unit,more » the solvent content was estimated to be about 47.9%. A complete data set was collected at 1.87 Å resolution.« less

  3. Crystallization and preliminary X-ray analysis of the Man(α1-2)Man-specific lectin from Bowringia mildbraedii in complex with its carbohydrate ligand

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

    Garcia-Pino, Abel; Loris, Remy; Wyns, Lode

    2005-10-01

    The lectin from the Nigerian legume B. mildbraedii was crystallized in complex with Man(α1-2)Man and data were collected to a resolution of 1.90 Å using synchrotron radiation. The lectin from Bowringia mildbraedii seeds crystallizes in the presence of the disaccharide Man(α1-2)Man. The best crystals grow at 293 K within four weeks after a pre-incubation at 277 K to induce nucleation. A complete data set was collected to a resolution of 1.90 Å using synchrotron radiation. The crystals belong to space group I222, with unit-cell parameters a = 66.06, b = 86.35, c = 91.76 Å, and contain one lectin monomermore » in the asymmetric unit.« less

  4. High glucose disrupts oligosaccharide recognition function via competitive inhibition: a potential mechanism for immune dysregulation in diabetes mellitus.

    PubMed

    Ilyas, Rebecca; Wallis, Russell; Soilleux, Elizabeth J; Townsend, Paul; Zehnder, Daniel; Tan, Bee K; Sim, Robert B; Lehnert, Hendrik; Randeva, Harpal S; Mitchell, Daniel A

    2011-01-01

    Diabetic complications include infection and cardiovascular disease. Within the immune system, host-pathogen and regulatory host-host interactions operate through binding of oligosaccharides by C-type lectin. A number of C-type lectins recognise oligosaccharides rich in mannose and fucose - sugars with similar structures to glucose. This raises the possibility that high glucose conditions in diabetes affect protein-oligosaccharide interactions via competitive inhibition. Mannose-binding lectin, soluble DC-SIGN and DC-SIGNR, and surfactant protein D, were tested for carbohydrate binding in the presence of glucose concentrations typical of diabetes, via surface plasmon resonance and affinity chromatography. Complement activation assays were performed in high glucose. DC-SIGN and DC-SIGNR expression in adipose tissues was examined via immunohistochemistry. High glucose inhibited C-type lectin binding to high-mannose glycoprotein and binding of DC-SIGN to fucosylated ligand (blood group B) was abrogated in high glucose. Complement activation via the lectin pathway was inhibited in high glucose and also in high trehalose - a nonreducing sugar with glucoside stereochemistry. DC-SIGN staining was seen on cells with DC morphology within omental and subcutaneous adipose tissues. We conclude that high glucose disrupts C-type lectin function, potentially illuminating new perspectives on susceptibility to infectious and inflammatory disease in diabetes. Mechanisms involve competitive inhibition of carbohydrate binding within sets of defined proteins, in contrast to broadly indiscriminate, irreversible glycation of proteins. Copyright © 2010 Elsevier GmbH. All rights reserved.

  5. Crystal structure of extracellular domain of human lectin-like transcript 1 (LLT1), the ligand for natural killer receptor-P1A.

    PubMed

    Kita, Shunsuke; Matsubara, Haruki; Kasai, Yoshiyuki; Tamaoki, Takaharu; Okabe, Yuki; Fukuhara, Hideo; Kamishikiryo, Jun; Krayukhina, Elena; Uchiyama, Susumu; Ose, Toyoyuki; Kuroki, Kimiko; Maenaka, Katsumi

    2015-06-01

    Emerging evidence has revealed the pivotal roles of C-type lectin-like receptors (CTLRs) in the regulation of a wide range of immune responses. Human natural killer cell receptor-P1A (NKRP1A) is one of the CTLRs and recognizes another CTLR, lectin-like transcript 1 (LLT1) on target cells to control NK, NKT and Th17 cells. The structural basis for the NKRP1A-LLT1 interaction was limitedly understood. Here, we report the crystal structure of the ectodomain of LLT1. The plausible receptor-binding face of the C-type lectin-like domain is flat, and forms an extended β-sheet. The residues of this face are relatively conserved with another CTLR, keratinocyte-associated C-type lectin, which binds to the CTLR member, NKp65. A LLT1-NKRP1A complex model, prepared using the crystal structures of LLT1 and the keratinocyte-associated C-type lectin-NKp65 complex, reasonably satisfies the charge consistency and the conformational complementarity to explain a previous mutagenesis study. Furthermore, crystal packing and analytical ultracentrifugation revealed dimer formation, which supports a complex model. Our results provide structural insights for understanding the binding modes and signal transduction mechanisms, which are likely to be conserved in the CTLR family, and for further rational drug design towards regulating the LLT1 function. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Changes in cell surface structure by viral transformation studied by binding of lectins differing in sugar specificity.

    PubMed

    Tsuda, M; Kurokawa, T; Takeuchi, M; Sugino, Y

    1975-10-01

    Changes in cell surface structure by viral transformation were studied by examining changes in the binding of various lectins differing in carbohydrate specificities. Binding of lectins was assayed directly using cells grown in coverslips. The following 125I-lectins were used: Concanavalin-A (specific for glucose and mannose), wheat germ agglutinin (specific for N-acetylglucosamine), castor bean agglutinin (specific for galactose), Wistaria floribunda agglutinin (specific for N-acetylgalactosamine), and soybean agglutinin (specific for N-acetyl-galactosamine). Cells for a clone, SS7, transformed by bovine adenovirus type-3, were found to bind 5 to 6 times more Wistaria floribunda agglutinin than the normal counterpart cells (clone C31, from C3H mouse kidney). In contrast, the binding of soybean agglutinin, which has a sugar specificity similar to Wistaria floribunda agglutinin, to normal and transformed cells was similar. The binding of wheat germ agglutinin and castor bean agglutinin, respectively, to normal and transformed cells was also similar. However, normal cells bound twice as much concanavalin-A as transformed cells. Only half as much Wistaria floribunda agglutinin was bound to transformed cells when they had been dispersed with EDTA. These changes in the number of lectin binding sites on transformation are thought to reflect alteration of the cell surface structure. The amount of lectins bound per cell decreased with increase in cell density, especially in the case of binding of Wistaria floribunda agglutinin to normal cells.

  7. Entry Inhibition of Influenza Viruses with High Mannose Binding Lectin ESA-2 from the Red Alga Eucheuma serra through the Recognition of Viral Hemagglutinin

    PubMed Central

    Sato, Yuichiro; Morimoto, Kinjiro; Kubo, Takanori; Sakaguchi, Takemasa; Nishizono, Akira; Hirayama, Makoto; Hori, Kanji

    2015-01-01

    Lectin sensitivity of the recent pandemic influenza A virus (H1N1-2009) was screened for 12 lectins with various carbohydrate specificity by a neutral red dye uptake assay with MDCK cells. Among them, a high mannose (HM)-binding anti-HIV lectin, ESA-2 from the red alga Eucheuma serra, showed the highest inhibition against infection with an EC50 of 12.4 nM. Moreover, ESA-2 exhibited a wide range of antiviral spectrum against various influenza strains with EC50s of pico molar to low nanomolar levels. Besides ESA-2, HM-binding plant lectin ConA, fucose-binding lectins such as fungal AOL from Aspergillus oryzae and AAL from Aleuria aurantia were active against H1N1-2009, but the potency of inhibition was of less magnitude compared with ESA-2. Direct interaction between ESA-2 and a viral envelope glycoprotein, hemagglutinin (HA), was demonstrated by ELISA assay. This interaction was effectively suppressed by glycoproteins bearing HM-glycans, indicating that ESA-2 binds to the HA of influenza virus through HM-glycans. Upon treatment with ESA-2, no viral antigens were detected in the host cells, indicating that ESA-2 inhibited the initial steps of virus entry into the cells. ESA-2 would thus be useful as a novel microbicide to prevent penetration of viruses such as HIV and influenza viruses to the host cells. PMID:26035023

  8. Lectin I from Bauhinia variegata (BVL-I) expressed by Pichia pastoris inhibits initial adhesion of oral bacteria in vitro.

    PubMed

    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.

  9. Altered glycosylation of complexed native IgG molecules is associated with disease activity of systemic lupus erythematosus.

    PubMed

    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 highest activity of systemic lupus erythematosus. Our results show that native circulating IgG complexes from active systemic lupus erythematosus patients expose fucosyl residues and their glycan core is accessible to soluble lectins. Two putative mechanisms may contribute to the increased exposure of these glycans: (1) the canonical N-glycosylation site of the IgG-CH2 domain; (2) an IgG binding non-IgG molecule, like complement or C-reactive protein. In both cases the complexed IgG may be alternatively targeted to lectin receptors of effector cells, e.g. dendritic cells. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  10. Fluorescence emission and polarization analyses for evaluating binding of ruthenium metalloglycoclusters to lectins and tetanus toxin C-fragment

    NASA Astrophysics Data System (ADS)

    Okada, Tomoko; Minoura, Norihiko

    2011-03-01

    We develop a fluorescent ruthenium metalloglycocluster for use as a powerful molecular probe in evaluating the binding between carbohydrates and lectins by fluorescence emission (FE) and fluorescence polarization (FP) analyses. Changes in the FE and FP of these metalloglycoclusters are measured following the addition of lectin [peanut agglutinin (PNA), Ricinus communis agglutinin 120, Concanavalin A (ConA), or wheat germ agglutinin] or tetanus toxin c-fragment (TCF). After the addition of PNA, the FE spectrum of [Ru(bpy-2Gal)3] shows a new emission peak and the FP value of [Ru(bpy-2Gal)3] increases. Similarly, the FE spectrum of [Ru(bpy-2Glc)3] shows a new emission peak and the FP value increases on addition of ConA. Because other combinations of metalloglycoclusters and lectins show little change, specific binding of galactose to PNA and that of glucose to ConA are confirmed by the FE and FP measurements. Resulting dissociation constants (Kd) prove that the metalloglycoclusters with highly clustered carbohydrates show higher affinity for the respective lectins than those with less clustered carbohydrates. Furthermore, specific binding of [Ru(bpy-2Gal)3] to TCF was confirmed by the FP measurement.

  11. Quantitative assessment of the multivalent protein-carbohydrate interactions on silicon.

    PubMed

    Yang, Jie; Chazalviel, Jean-Noël; Siriwardena, Aloysius; Boukherroub, Rabah; Ozanam, François; Szunerits, Sabine; Gouget-Laemmel, Anne Chantal

    2014-10-21

    A key challenge in the development of glycan arrays is that the sensing interface be fabricated reliably so as to ensure the sensitive and accurate analysis of the protein-carbohydrate interaction of interest, reproducibly. These goals are complicated in the case of glycan arrays as surface sugar density can influence dramatically the strength and mode of interaction of the sugar ligand at any interface with lectin partners. In this Article, we describe the preparation of carboxydecyl-terminated crystalline silicon (111) surfaces onto which are grafted either mannosyl moieties or a mixture of mannose and spacer alcohol molecules to provide "diluted" surfaces. The fabrication of the silicon surfaces was achieved efficiently through a strategy implicating a "click" coupling step. The interactions of these newly fabricated glycan interfaces with the lectin, Lens culinaris, have been characterized using quantitative infrared (IR) spectroscopy in the attenuated total geometry (ATR). The density of mannose probes and lectin targets was precisely determined for the first time by the aid of special IR calibration experiments, thus allowing for the interpretation of the distribution of mannose and its multivalent binding with lectins. These experimental findings were accounted for by numerical simulations of lectin adsorption.

  12. Mannan-binding lectin of the sea urchin Strongylocentrotus nudus.

    PubMed

    Bulgakov, Aleksandr A; Eliseikina, Marina G; Kovalchuk, Svetlana N; Petrova, Irina Yu; Likhatskaya, Galina N; Shamshurina, Ekaterina V; Rasskazov, Valery A

    2013-02-01

    A novel lectin specific to low-branched mannans (MBL-SN) was isolated from coelomic plasma of the sea urchin Strongylocentrotus nudus by combining anion-exchange liquid chromatography on DEAE Toyopearl 650 M, affinity chromatography on mannan-Sepharose and gel filtration on the Sephacryl S-200. The molecular mass of MBL-SN was estimated by sodium dodecyl sulphate polyacrylamide gel electrophoresis under non-reducing conditions to be about 34 kDa. MBL-SN was shown to be a dimer with two identical subunits of about 17 kDa. The native MBL-SN exists as a tetramer. The physico-chemical properties of MBL-SN indicate that it belongs to C-type mannan-binding lectins. The cDNA encoding MBL-SN was cloned from the total cDNA of S. nudus coelomocytes and encodes a 17-kDa protein of 144 amino acid residues that contains a single carbohydrate-recognition domain of C-type lectins. Prediction of the MBL-SN tertiary structure using comparative modelling revealed that MBL-SN is an α/β-protein with eight β-strands and two α-helices. Comparison of the MBL-SN model with available three-dimensional structures of C-type lectins revealed that they share a common fold pattern.

  13. Fungal lectin MpL enables entry of protein drugs into cancer cells and their subcellular targeting.

    PubMed

    Å Urga, Simon; Nanut, Milica Perišić; Kos, Janko; Sabotič, Jerica

    2017-04-18

    Lectins have been recognized as promising carrier molecules for targeted drug delivery. They specifically bind carbohydrate moieties on cell membranes and trigger cell internalization. Fungal lectin MpL (Macrolepiota procera lectin) does not provoke cancer cell cytotoxicity but is able to bind aminopeptidase N (CD13) and integrin α3β1, two glycoproteins that are overexpressed on the membrane of tumor cells. Upon binding, MpL is endocytosed in a clathrin-dependent manner and accumulates initially in the Golgi apparatus and, finally, in the lysosomes. For effective binding and internalization a functional binding site on the α-repeat is needed. To test the potential of MpL as a carrier for delivering protein drugs to cancer cells we constructed fusion proteins consisting of MpL and the cysteine peptidase inhibitors cystatin C and clitocypin. The fused proteins followed the same endocytic route as the unlinked MpL. Peptidase inhibitor-MpL fusions impaired both the intracellular degradation of extracellular matrix and the invasiveness of cancer cells. MpL is thus shown in vitro to be a lectin that can enable protein drugs to enter cancer cells, enhance their internalization and sort them to lysosomes and the Golgi apparatus.

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

    PubMed

    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.

  15. Dynamic light scattering as an efficient tool to study glyconanoparticle-lectin interactions.

    PubMed

    Wang, Xin; Ramström, Olof; Yan, Mingdi

    2011-10-21

    Glyconanomaterials, an emerging class of bio-functional nanomaterials, have shown promise in detecting, imaging and targeting proteins, bacteria, and cells. In this article, we report that dynamic light scattering (DLS) can be used as an efficient tool to study glyconanoparticle (GNP)--lectin interactions. Silica and Au nanoparticles (NPs) conjugated with D-mannose (Man) and D-galactose (Gal) were treated with the lectins Concanavalin A (Con A) and Ricinus communis agglutinin (RCA(120)), and the hydrodynamic volumes of the resulting aggregates were measured by DLS. The results showed that the particle size grew with increasing lectin concentration. The limit of detection (LOD) was determined to be 2.9 nM for Con A with Man-conjugated and 6.6 nM for RCA(120) with Gal-conjugated silica NPs (35 nm), respectively. The binding affinity was also determined by DLS and the results showed 3-4 orders of magnitude higher affinity of GNPs than the free ligands with lectins. The assay sensitivity and affinity were particle size dependent and decreased with increasing particle diameter. Because the method relies on the particle size growth, it is therefore general and can be applied to nanomaterials of different compositions.

  16. Purification, characterization, and biological activities of broccolini lectin.

    PubMed

    Xu, Pingping; Zhang, Ting; Guo, Xiaolei; Ma, Chungwah; Zhang, Xuewu

    2015-01-01

    Plant lectins have displayed a variety of biological activities. In this study, for the first time, a 27 kDa arabinose- and mannose-specific lectin from Broccolini (Brassica oleracea Italica × Alboglabra), named as BL (Broccolini lectin), was purified by an activity-driven protocol. Mass spectrometry analysis and database search indicated that no matches with any plant lectin were found, but BL contained some peptide fragments (QQQGQQGQQLQQVISR, QQGQQQGQQGQQLQQVISR and VCNIPQVSVCPF QK). BL exhibited hemagglutinating activity against chicken erythrocytes at 4 µg/mL. BL retained full hemagglutinating activity at pH 7-8 and temperature 30-40°C, and had an optimal activity in Ca(2+) solution. Bioactivity assay revealed that BL exhibited dose-dependent inhibition activity on 5 bacterial species with IC50 values of 143.95-486.33 μg/mL, and on 3 cancer cells with IC50 values of 178.82-350.93 μg/mL. Notably, 5-fold reduction in IC50 values was observed on normal L-O2 vs cancerous HepG-2 cells (924.35 vs. 178.82 μg/mL). This suggests that BL should be promising in food and medicine. © 2015 American Institute of Chemical Engineers.

  17. Purification and partial characterization of a lectin protein complex, the clathrilectin, from the calcareous sponge Clathrina clathrus.

    PubMed

    Gardères, Johan; Domart-Coulon, Isabelle; Marie, Arul; Hamer, Bojan; Batel, Renato; Müller, Werner E G; Bourguet-Kondracki, Marie-Lise

    2016-10-01

    Carbohydrate-binding proteins were purified from the marine calcareous sponge Clathrina clathrus via affinity chromatography on lactose and N-acetyl glucosamine-agarose resins. Proteomic analysis of acrylamide gel separated protein subunits obtained in reducing conditions pointed out several candidates for lectins. Based on amino-acid sequence similarity, two peptides displayed homology with the jack bean lectin Concanavalin A, including a conserved domain shared by proteins in the L-type lectin superfamily. An N-acetyl glucosamine - binding protein complex, named clathrilectin, was further purified via gel filtration chromatography, bioguided with a diagnostic rabbit erythrocyte haemagglutination assay, and its activity was found to be calcium dependent. Clathrilectin, a protein complex of 3200kDa estimated by gel filtration, is composed of monomers with apparent molecular masses of 208 and 180kDa estimated on 10% SDS-PAGE. Nine internal peptides were identified using proteomic analyses, and compared to protein libraries from the demosponge Amphimedon queenslandica and a calcareous sponge Sycon sp. from the Adriatic Sea. The clathrilectin is the first lectin isolated from a calcareous sponge and displays homologies with predicted sponge proteins potentially involved in cell aggregation and interaction with bacteria. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Crystallization and X-ray analysis of the salmon-egg lectin SEL24K

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

    Murata, Kenji; Fisher, Andrew J.; Hedrick, Jerry L., E-mail: jlhedrick@ucdavis.edu

    2007-05-01

    The 24 kDa egg lectin of Chinook salmon (Oncorhynchus tshawytscha) was purified by affinity chromatography from salmon eggs and crystallized by the hanging-drop vapor-diffusion method using 15/4 EO/OH (pentaerythritol ethoxylate) as a precipitant. The 24 kDa egg lectin of Chinook salmon (Oncorhynchus tshawytscha) is released from the egg during the cortical reaction. The lectin functions in blocking polyspermy during the fertilization process. The egg lectin was purified by affinity chromatography from salmon eggs and crystallized by the hanging-drop vapor-diffusion method using 15/4 EO/OH (pentaerythritol ethoxylate) as a precipitant. The crystal diffracted synchrotron-radiation X-rays to 1.63 Å resolution. The crystal belongsmore » to the monoclinic space group P2{sub 1}, with unit-cell parameters a = 93.0, b = 73.6, c = 113.6 Å, α = 90, β = 92.82, γ = 90°. The crystal is likely to contain eight molecules in the asymmetric unit (V{sub M} = 2.3 Å{sup 3} Da{sup −1}), corresponding to a solvent content of 45.5%. A self-rotation function suggests an arrangement with 222 point symmetry within the asymmetric unit.« less

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

    PubMed

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

    1988-09-01

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

  20. Seasonal Fluctuations of Lectins in Barks of Elderberry (Sambucus nigra) and Black Locust (Robinia pseudoacacia) 1

    PubMed Central

    Nsimba-Lubaki, Makuta; Peumans, Willy J.

    1986-01-01

    Elderberry (Sambucus nigra) and black locust (Robinia pseudoacacia) agglutinins, which are abundantly present in the bark of both species, display seasonal fluctuations with regard to their content in this tissue. These seasonal changes result apparently from a circa-annual rhythm of lectin accumulation and depletion during autumn and spring, respectively. Because the bark of trees can be considered as a type of vegetative storage tissue, the results suggest that bark lectins behave as typical storage proteins. Images Fig. 4 PMID:16664696

  1. Rapid assays for lectin toxicity and binding changes that reflect altered glycosylation in mammalian cells.

    PubMed

    Stanley, Pamela; Sundaram, Subha

    2014-06-03

    Glycosylation engineering is used to generate glycoproteins, glycolipids, or proteoglycans with a more defined complement of glycans on their glycoconjugates. For example, a mammalian cell glycosylation mutant lacking a specific glycosyltransferase generates glycoproteins, and/or glycolipids, and/or proteoglycans with truncated glycans missing the sugar transferred by that glycosyltransferase, as well as those sugars that would be added subsequently. In some cases, an alternative glycosyltransferase may then use the truncated glycans as acceptors, thereby generating a new or different glycan subset in the mutant cell. Another type of glycosylation mutant arises from gain-of-function mutations that, for example, activate a silent glycosyltransferase gene. In this case, glycoconjugates will have glycans with additional sugar(s) that are more elaborate than the glycans of wild type cells. Mutations in other genes that affect glycosylation, such as nucleotide sugar synthases or transporters, will alter the glycan complement in more general ways that usually affect several types of glycoconjugates. There are now many strategies for generating a precise mutation in a glycosylation gene in a mammalian cell. Large-volume cultures of mammalian cells may also generate spontaneous mutants in glycosylation pathways. This article will focus on how to rapidly characterize mammalian cells with an altered glycosylation activity. The key reagents for the protocols described are plant lectins that bind mammalian glycans with varying avidities, depending on the specific structure of those glycans. Cells with altered glycosylation generally become resistant or hypersensitive to lectin toxicity, and have reduced or increased lectin or antibody binding. Here we describe rapid assays to compare the cytotoxicity of lectins in a lectin resistance test, and the binding of lectins or antibodies by flow cytometry in a glycan-binding assay. Based on these tests, glycosylation changes expressed by a cell can be revealed, and glycosylation mutants classified into phenotypic groups that may reflect a loss-of-function or gain-of-function mutation in a specific gene involved in glycan synthesis. Copyright © 2014 John Wiley & Sons, Inc.

  2. A scallop C-type lectin from Argopecten irradians (AiCTL5) with activities of lipopolysaccharide binding and Gram-negative bacteria agglutination.

    PubMed

    Mu, Changkao; Song, Xiaoyan; Zhao, Jianmin; Wang, Lingling; Qiu, Limei; Zhang, Huan; Zhou, Zhi; Wang, Mengqiang; Song, Linsheng; Wang, Chunlin

    2012-05-01

    C-type lectins are a family of calcium-dependent carbohydrate-binding proteins. In the present study, a C-type lectin (designated as AiCTL5) was identified and characterized from Argopecten irradians. The full-length cDNA of AiCTL5 was of 673 bp, containing a 5' untranslated region (UTR) of 24 bp, a 3' UTR of 130 bp with a poly (A) tail, and an open reading frame (ORF) of 519 bp encoding a polypeptide of 172 amino acids with a putative signal peptide of 17 amino acids. A C-type lectin-like domain (CRD) containing 6 conserved cysteines and a putative glycosylation sites were identified in the deduced amino acid sequence of AiCTL5. AiCTL5 shared 11%-27.5% identity with the previous reported C-type lectin from A. irradians. The cDNA fragment encoding the mature peptide of AiCTL5 was recombined into pET-21a (+) with a C-terminal hexa-histidine tag fused in-frame, and expressed in Escherichia coli Origami (DE3). The recombinant AiCTL5 (rAiCTL5) agglutinated Gram-negative E. coli TOP10F' and Listonella anguillarum, but did not agglutinate Gram-positive bacteria Bacillus thuringiensis and Micrococcus luteus, and the agglutination could be inhibited by EDTA, indicating that AiCTL5 was a Ca(2+)-dependent lectin. rAiCTL5 exhibited a significantly strong activity to bind LPS from E. coli, which conformed to the agglutinating activity toward Gram-negative bacteria. Moreover, rAiCTL5 also agglutinated rabbit erythrocytes. These results indicated that AiCTL5 could function as a pattern recognition receptor to protect bay scallop from Gram-negative bacterial infection, and also provide evidence to understand the structural and functional diverse of lectin. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

    PubMed

    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.

  4. A Jacalin-Related Lectin Regulated the Formation of Aerial Mycelium and Fruiting Body in Flammulina velutipes

    PubMed Central

    Lu, Yuan-Ping; Chen, Ren-Liang; Long, Ying; Li, Xiao; Jiang, Yu-Ji; Xie, Bao-Gui

    2016-01-01

    Flammulina velutipes, one of the most popular mushroom species in the world, has been recognized as a useful model system to study the biochemical and physiological aspects of the formation and elongation of fruit body. However, few reports have been published on the regulation of fruiting body formation in F. velutipes at the molecular level. In this study, a jacalin-related lectin gene from F. velutipes was characterized. The phylogenetic tree revealed that Fv-JRL1 clustered with other basidiomycete jacalin-like lectins. Moreover, the transcriptional pattern of the Fv-JRL1 gene in different developmental stages of F. velutipes implied that Fv-JRL1 could be important for formation of fruit body. Additionally, RNA interference (RNAi) and overexpression analyses provided powerful evidence that the lectin gene Fv-JRL1 from F. velutipes plays important roles in fruiting body formation. PMID:27916794

  5. Crystallization and X-ray analysis of the salmon-egg lectin SEL24K.

    PubMed

    Murata, Kenji; Fisher, Andrew J; Hedrick, Jerry L

    2007-05-01

    The 24 kDa egg lectin of Chinook salmon (Oncorhynchus tshawytscha) is released from the egg during the cortical reaction. The lectin functions in blocking polyspermy during the fertilization process. The egg lectin was purified by affinity chromatography from salmon eggs and crystallized by the hanging-drop vapor-diffusion method using 15/4 EO/OH (pentaerythritol ethoxylate) as a precipitant. The crystal diffracted synchrotron-radiation X-rays to 1.63 A resolution. The crystal belongs to the monoclinic space group P2(1), with unit-cell parameters a = 93.0, b = 73.6, c = 113.6 A, alpha = 90, beta = 92.82, gamma = 90 degrees. The crystal is likely to contain eight molecules in the asymmetric unit (V(M) = 2.3 A3 Da(-1)), corresponding to a solvent content of 45.5%. A self-rotation function suggests an arrangement with 222 point symmetry within the asymmetric unit.

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

    PubMed

    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.

  7. Bivalent O-glycoside mimetics with S/disulfide/Se substitutions and aromatic core: Synthesis, molecular modeling and inhibitory activity on biomedically relevant lectins in assays of increasing physiological relevance.

    PubMed

    Kaltner, Herbert; Szabó, Tamás; Fehér, Krisztina; André, Sabine; Balla, Sára; Manning, Joachim C; Szilágyi, László; Gabius, Hans-Joachim

    2017-06-15

    The emerging significance of recognition of cellular glycans by lectins for diverse aspects of pathophysiology is a strong incentive for considering development of bioactive and non-hydrolyzable glycoside derivatives, for example by introducing S/Se atoms and the disulfide group instead of oxygen into the glycosidic linkage. We report the synthesis of 12 bivalent thio-, disulfido- and selenoglycosides attached to benzene/naphthalene cores. They present galactose, for blocking a plant toxin, or lactose, the canonical ligand of adhesion/growth-regulatory galectins. Modeling reveals unrestrained flexibility and inter-headgroup distances too small to bridge two sites in the same lectin. Inhibitory activity was first detected by solid-phase assays using a surface-presented glycoprotein, with relative activity enhancements per sugar unit relative to free cognate sugar up to nearly 10fold. Inhibitory activity was also seen on lectin binding to surfaces of human carcinoma cells. In order to proceed to characterize this capacity in the tissue context monitoring of lectin binding in the presence of inhibitors was extended to sections of three types of murine organs as models. This procedure proved to be well-suited to determine relative activity levels of the glycocompounds to block binding of the toxin and different human galectins to natural glycoconjugates at different sites in sections. The results on most effective inhibition by two naphthalene-based disulfides and a selenide raise the perspective for broad applicability of the histochemical assay in testing glycoclusters that target biomedically relevant lectins. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Structural Investigation of a Novel N-Acetyl Glucosamine Binding Chi-Lectin Which Reveals Evolutionary Relationship with Class III Chitinases

    PubMed Central

    Patil, Dipak N.; Datta, Manali; Dev, Aditya; Dhindwal, Sonali; Singh, Nirpendra; Dasauni, Pushpanjali; Kundu, Suman; Sharma, Ashwani K.; Tomar, Shailly; Kumar, Pravindra

    2013-01-01

    The glycosyl hydrolase 18 (GH18) family consists of active chitinases as well as chitinase like lectins/proteins (CLPs). The CLPs share significant sequence and structural similarities with active chitinases, however, do not display chitinase activity. Some of these proteins are reported to have specific functions and carbohydrate binding property. In the present study, we report a novel chitinase like lectin (TCLL) from Tamarindus indica. The crystal structures of native TCLL and its complex with N-acetyl glucosamine were determined. Similar to the other CLPs of the GH18 members, TCLL lacks chitinase activity due to mutations of key active site residues. Comparison of TCLL with chitinases and other chitin binding CLPs shows that TCLL has substitution of some chitin binding site residues and more open binding cleft due to major differences in the loop region. Interestingly, the biochemical studies suggest that TCLL is an N-acetyl glucosamine specific chi-lectin, which is further confirmed by the complex structure of TCLL with N-acetyl glucosamine complex. TCLL has two distinct N-acetyl glucosamine binding sites S1 and S2 that contain similar polar residues, although interaction pattern with N-acetyl glucosamine varies extensively among them. Moreover, TCLL structure depicts that how plants utilize existing structural scaffolds ingenuously to attain new functions. To date, this is the first structural investigation of a chi-lectin from plants that explore novel carbohydrate binding sites other than chitin binding groove observed in GH18 family members. Consequently, TCLL structure confers evidence for evolutionary link of lectins with chitinases. PMID:23717482

  9. Subtle Differences in Symbiont Cell Surface Glycan Profiles Do Not Explain Species-Specific Colonization Rates in a Model Cnidarian-Algal Symbiosis

    PubMed Central

    Parkinson, John E.; Tivey, Trevor R.; Mandelare, Paige E.; Adpressa, Donovon A.; Loesgen, Sandra; Weis, Virginia M.

    2018-01-01

    Mutualisms between cnidarian hosts and dinoflagellate endosymbionts are foundational to coral reef ecosystems. These symbioses are often re-established every generation with high specificity, but gaps remain in our understanding of the cellular mechanisms that control symbiont recognition and uptake dynamics. Here, we tested whether differences in glycan profiles among different symbiont species account for the different rates at which they initially colonize aposymbiotic polyps of the model sea anemone Aiptasia (Exaiptasia pallida). First, we used a lectin array to characterize the glycan profiles of colonizing Symbiodinium minutum (ITS2 type B1) and noncolonizing Symbiodinium pilosum (ITS2 type A2), finding subtle differences in the binding of lectins Euonymus europaeus lectin (EEL) and Urtica dioica agglutinin lectin (UDA) that distinguish between high-mannoside and hybrid-type protein linked glycans. Next, we enzymatically cleaved glycans from the surfaces of S. minutum cultures and followed their recovery using flow cytometry, establishing a 48–72 h glycan turnover rate for this species. Finally, we exposed aposymbiotic host polyps to cultured S. minutum cells masked by EEL or UDA lectins for 48 h, then measured cell densities the following day. We found no effect of glycan masking on symbiont density, providing further support to the hypothesis that glycan-lectin interactions are more important for post-phagocytic persistence of specific symbionts than they are for initial uptake. We also identified several methodological and biological factors that may limit the utility of studying glycan masking in the Aiptasia system. PMID:29765363

  10. Lectindb: a plant lectin database.

    PubMed

    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.

  11. Prevalence of the F-type lectin domain.

    PubMed

    Bishnoi, Ritika; Khatri, Indu; Subramanian, Srikrishna; Ramya, T N C

    2015-08-01

    F-type lectins are fucolectins with characteristic fucose and calcium-binding sequence motifs and a unique lectin fold (the "F-type" fold). F-type lectins are phylogenetically widespread with selective distribution. Several eukaryotic F-type lectins have been biochemically and structurally characterized, and the F-type lectin domain (FLD) has also been studied in the bacterial proteins, Streptococcus mitis lectinolysin and Streptococcus pneumoniae SP2159. However, there is little knowledge about the extent of occurrence of FLDs and their domain organization, especially, in bacteria. We have now mined the extensive genomic sequence information available in the public databases with sensitive sequence search techniques in order to exhaustively survey prokaryotic and eukaryotic FLDs. We report 437 FLD sequence clusters (clustered at 80% sequence identity) from eukaryotic, eubacterial and viral proteins. Domain architectures are diverse but mostly conserved in closely related organisms, and domain organizations of bacterial FLD-containing proteins are very different from their eukaryotic counterparts, suggesting unique specialization of FLDs to suit different requirements. Several atypical phylogenetic associations hint at lateral transfer. Among eukaryotes, we observe an expansion of FLDs in terms of occurrence and domain organization diversity in the taxa Mollusca, Hemichordata and Branchiostomi, perhaps coinciding with greater emphasis on innate immune strategies in these organisms. The naturally occurring FLDs with diverse domain organizations that we have identified here will be useful for future studies aimed at creating designer molecular platforms for directing desired biological activities to fucosylated glycoconjugates in target niches. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Titanium dioxide nanotubes functionalized with Cratylia mollis seed lectin, Cramoll, enhanced osteoblast-like cells adhesion and proliferation.

    PubMed

    Oliveira, Weslley F; Silva, Germana M M; Cabral Filho, Paulo E; Fontes, Adriana; Oliveira, Maria D L; Andrade, César A S; Silva, Márcia V; Coelho, Luana C B B; Machado, Giovanna; Correia, Maria T S

    2018-09-01

    An alternative to accelerate the osseointegration on titanium dioxide nanotubes (TNTs) used in osseointegrated implants is through the functionalization of these nanostructured surfaces with biomolecules. In this work, we immobilized a lectin with recognized mitogenic activity, the Cramoll lectin, extracted from Cratylia mollis seeds, on surfaces modified by TNTs. For the immobilization of Cramoll on TNTs surfaces, we used the Layer-by-Layer technique (LbL) by growing five alternate layers of poly(allylamine) hydrochloride (PAH) and poly(acrylic) acid (PAA); lastly we incubated the lectin, at different concentrations, with the TNTs-LbL. Before and after the immobilization procedures, the substrate surfaces were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and, electrochemical impedance spectroscopy (EIS). We also evaluated the Cramoll activity after immobilization on TNTs by using the lectin interaction with ovalbumin. The lectin did not lose its biological activity, even after immobilization onto nanotubular arrays. In addition, we observed an increase osteoblast-like cell adhesion on the TNTs-LbL-Cramoll system when compared to the bare TNTs surfaces. Moreover, a significative cell proliferation was identified on the substrates when Cramoll was immobilized at concentrations of 80, 160 and 320 μg/mL after 48 h of incubation by using the resazurin assay. Our results suggest that Cramoll was efficiently immobilized on a nanotubular array and this new platform presents a great potential to be tested in implantology. Copyright © 2018 Elsevier B.V. All rights reserved.

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

    PubMed

    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.

  14. Role of Ficolin-A and Lectin Complement Pathway in the Innate Defense against Pathogenic Aspergillus Species

    PubMed Central

    Bidula, Stefan; Kenawy, Hany; Ali, Youssif M.; Sexton, Darren; Schwaeble, Wilhelm J.

    2013-01-01

    Aspergillus species are saprophytic molds causing life-threatening invasive fungal infections in the immunocompromised host. Innate immune recognition, in particular, the mechanisms of opsonization and complement activation, has been reported to be an integral part of the defense against fungi. We have shown that the complement component ficolin-A significantly binds to Aspergillus conidia and hyphae in a concentration-dependent manner and was inhibited by N-acetylglucosamine and N-acetylgalactosamine. Calcium-independent binding to Aspergillus fumigatus and A. terreus was observed, but binding to A. flavus and A. niger was calcium dependent. Ficolin-A binding to conidia was increased under low-pH conditions, and opsonization led to enhanced binding of conidia to A549 airway epithelial cells. In investigations of the lectin pathway of complement activation, ficolin-A-opsonized conidia did not lead to lectin pathway-specific C4 deposition. In contrast, the collectin mannose binding lectin C (MBL-C) but not MBL-A led to efficient lectin pathway activation on A. fumigatus in the absence of ficolin-A. In addition, ficolin-A opsonization led to a modulation of the proinflammatory cytokine interleukin-8. We conclude that ficolin-A may play an important role in the innate defense against Aspergillus by opsonizing conidia, immobilizing this fungus through enhanced adherence to epithelial cells and modulation of inflammation. However, it appears that other immune pattern recognition molecules, i.e., those of the collectin MBL-C, are involved in the Aspergillus-lectin complement pathway activation rather than ficolin-A. PMID:23478320

  15. The gene for stinging nettle lectin (Urtica dioica agglutinin) encodes both a lectin and a chitinase.

    PubMed

    Lerner, D R; Raikhel, N V

    1992-06-05

    Chitin-binding proteins are present in a wide range of plant species, including both monocots and dicots, even though these plants contain no chitin. To investigate the relationship between in vitro antifungal and insecticidal activities of chitin-binding proteins and their unknown endogenous functions, the stinging nettle lectin (Urtica dioica agglutinin, UDA) cDNA was cloned using a synthetic gene as the probe. The nettle lectin cDNA clone contained an open reading frame encoding 374 amino acids. Analysis of the deduced amino acid sequence revealed a 21-amino acid putative signal sequence and the 86 amino acids encoding the two chitin-binding domains of nettle lectin. These domains were fused to a 19-amino acid "spacer" domain and a 244-amino acid carboxyl extension with partial identity to a chitinase catalytic domain. The authenticity of the cDNA clone was confirmed by deduced amino acid sequence identity with sequence data obtained from tryptic digests, RNA gel blot, and polymerase chain reaction analyses. RNA gel blot analysis also showed the nettle lectin message was present primarily in rhizomes and inflorescence (with immature seeds) but not in leaves or stems. Chitinase enzymatic activity was found when the chitinase-like domain alone or the chitinase-like domain with the chitin-binding domains were expressed in Escherichia coli. This is the first example of a chitin-binding protein with both a duplication of the 43-amino acid chitin-binding domain and a fusion of the chitin-binding domains to a structurally unrelated domain, the chitinase domain.

  16. Candida glabrata binds to glycosylated and lectinic receptors on the coronary endothelial luminal membrane and inhibits flow sense and cardiac responses to agonists.

    PubMed

    Torres-Tirado, David; Knabb, Maureen; Castaño, Irene; Patrón-Soberano, Araceli; De Las Peñas, Alejandro; Rubio, Rafael

    2016-01-01

    Candida glabrata (CG) is an opportunistic fungal pathogen that initiates infection by binding to host cells via specific lectin-like adhesin proteins. We have previously shown the importance of lectin-oligosaccharide binding in cardiac responses to flow and agonists. Because of the lectinic-oligosaccharide nature of CG binding, we tested the ability of CG to alter the agonist- and flow-induced changes in cardiac function in isolated perfused guinea pig hearts. Both transmission and scanning electron microscopy showed strong attachment of CG to the coronary endothelium, even after extensive washing. CG shifted the coronary flow vs. auricular-ventricular (AV) delay relationship upward, indicating that greater flow was required to achieve the same AV delay. This effect was completely reversed with mannose, partially reversed with galactose and N-acetylgalactosamine, but hyaluronan had no effect. Western blot analysis was used to determine binding of CG to isolated coronary endothelial luminal membrane (CELM) receptors, and the results indicate that flow-sensitive CELM receptors, ANG II type I, α-adrenergic 1A receptor, endothelin-2, and VCAM-1 bind to CG. In addition, CG inhibited agonist-induced effects of bradykinin, angiotensin, and phenylephrine on AV delay, coronary perfusion pressure, and left ventricular pressure. Mannose reversed the inhibitory effects of CG on the agonist responses. These results suggest that CG directly binds to flow-sensitive CELM receptors via lectinic-oligosaccharide interactions with mannose and disrupts the lectin-oligosaccharide binding necessary for flow-induced cardiac responses. Copyright © 2016 the American Physiological Society.

  17. PmLT, a C-type lectin specific to hepatopancreas is involved in the innate defense of the shrimp Penaeus monodon.

    PubMed

    Ma, Tracy Hoi-Tung; Benzie, John A H; He, Jian-Guo; Chan, Siu-Ming

    2008-11-01

    A diverse class of proteins called lectins plays a major role in shrimp innate immunity. In this study, the cDNA encoding a C-type lectin of Penaeus monodon (PmLT) was cloned, and its potential role examined. Despite the low overall amino acid sequence identity with other animal lectins, PmLT includes conserved carbohydrate recognition domains (CRDs) characteristic of animal C-type lectins. Unlike the other two P. monodon lectin-like proteins described to date that have one CRD, PmLT has two CRDs. The first CRD contains a QPD motif with specificity for binding galactose, while the second CRD contains a EPN motif for binding mannose. PmLT transcripts can be detected in the hepatopancreas but not in other tissues. Expression studies showed that PmLT mRNA transcript level decreased initially and then gradually increased after whole shrimp or hepatopancreas tissue fragments were treated with white spot syndrome virus (WSSV) extract but were not affected by bacteria. Using anti-rPmLT antibody, PmLT was detected only in the hepatopancreas specific F cells (Hpf). In vitro encapsulation assay showed that agarose beads coated with rPmLT were encapsulated by hemocytes indicating a role in innate immune response. In summary, PmLT is produced in the hepatopancreas and may act as a pattern recognition protein for viral pathogens and also activates the innate immune responses of the shrimp to bacteria. The dual-CRD structure of PmLT may assist the recognition of diverse pathogens.

  18. 15 CFR 742.18 - Chemical Weapons Convention (CWC or Convention).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ricin in the form of Ricinus Communis AgglutininII (RCAII), which is also known as ricin D or Ricinus Communis LectinIII (RCLIII), and Ricinus Communis LectinIV (RCLIV), which is also known as ricin E. CW...

  19. 15 CFR 742.18 - Chemical Weapons Convention (CWC or Convention).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ricin in the form of Ricinus Communis AgglutininII (RCAII), which is also known as ricin D or Ricinus Communis LectinIII (RCLIII), and Ricinus Communis LectinIV (RCLIV), which is also known as ricin E. CW...

  20. 15 CFR 742.18 - Chemical Weapons Convention (CWC or Convention).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ricin in the form of Ricinus Communis AgglutininII (RCAII), which is also known as ricin D or Ricinus Communis LectinIII (RCLIII), and Ricinus Communis LectinIV (RCLIV), which is also known as ricin E. CW...

  1. Identification of a Gal/GalNAc Lectin in the Protozoan Hartmannella vermiformis as a Potential Receptor for Attachment and Invasion by the Legionnaires' Disease Bacterium

    PubMed Central

    Venkataraman, Chandrasekar; Haack, Bradley J.; Bondada, Subbarao; Kwaik, Yousef Abu

    1997-01-01

    The Legionnaire's disease bacterium, Legionella pneumophila, is a facultative intracellular pathogen which invades and replicates within two evolutionarily distant hosts, free-living protozoa and mammalian cells. Invasion and intracellular replication within protozoa are thought to be major factors in the transmission of Legionnaire's disease. Although attachment and invasion of human macrophages by L. pneumophila is mediated in part by the complement receptors CR1 and CR3, the protozoan receptor involved in bacterial attachment and invasion has not been identified. To define the molecular events involved in invasion of protozoa by L. pneumophila, we examined the role of protein tyrosine phosphorylation of the protozoan host Hartmannella vermiformis upon attachment and invasion by L. pneumophila. Bacterial attachment and invasion were associated with a time-dependent tyrosine dephosphorylation of multiple host cell proteins. This host cell response was highly specific for live L. pneumophila, required contact with viable bacteria, and was completely reversible following washing off the bacteria from the host cell surface. Tyrosine dephosphorylation of host proteins was blocked by a tyrosine phosphatase inhibitor but not by tyrosine kinase inhibitors. One of the tyrosine dephosphorylated proteins was identified as the 170-kD galactose/N-acetylgalactosamine–inhibitable lectin (Gal/GalNAc) using immunoprecipitation and immunoblotting by antibodies generated against the Gal/GalNAc lectin of the protozoan Entamoeba histolytica. This Gal/GalNAc–inhibitable lectin has been shown previously to mediate adherence of E. histolytica to mammalian epithelial cells. Uptake of L. pneumophila by H. vermiformis was specifically inhibited by two monovalent sugars, Gal and GalNAc, and by mABs generated against the 170-kD lectin of E. histolytica. Interestingly, inhibition of invasion by Gal and GalNAc was associated with inhibition of bacterial-induced tyrosine dephosphorylation of H. vermiformis proteins. High stringency DNA hybridization confirmed the presence of the 170-kD lectin gene in H. vermiformis. We conclude that attachment of L. pneumophila to the H. vermiformis 170-kD lectin is required for invasion and is associated with tyrosine dephosphorylation of the Gal lectin and other host proteins. This is the first demonstration of a potential receptor used by L. pneumophila to invade protozoa. PMID:9254652

  2. Lectin Ulex europaeus agglutinin I specifically labels a subset of primary afferent fibers which project selectively to the superficial dorsal horn of the spinal cord.

    PubMed

    Mori, K

    1986-02-19

    To examine differential carbohydrate expression among different subsets of primary afferent fibers, several fluorescein-isothiocyanate conjugated lectins were used in a histochemical study of the dorsal root ganglion (DRG) and spinal cord of the rabbit. The lectin Ulex europaeus agglutinin I specifically labeled a subset of DRG cells and primary afferent fibers which projected to the superficial laminae of the dorsal horn. These results suggest that specific carbohydrates containing L-fucosyl residue is expressed selectively in small diameter primary afferent fibers which subserve nociception or thermoception.

  3. Development of glycan specific lectin based immunoassay for detection of prostate specific antigen.

    PubMed

    Bhanushali, Paresh B; Badgujar, Shamkant B; Tripathi, Mukesh M; Gupta, Sanjeev; Murthy, Vedang; Krishnasastry, Musti V; Puri, Chander P

    2016-05-01

    We describe an analytical approach for the detection and verification of glycosylation patterns of prostate specific antigen (PSA), a key biomarker currently used for understanding the onset and prognosis of prostate cancer. PSA has been purified from the human seminal plasma and total PSA from prostate cancer sera. PSA is a monomeric glycoprotein with an apparent molecular mass 28040.467 Da, which exhibits a characteristic protease activity against casein and gelatin. Its optimal protease activity is centered on neutral pH. Peptide mass fingerprint analysis of the purified PSA has yielded peptides that partially match with known database sequences (Uniprot ID P07288). Tryptic digestion profile of isolated PSA, infer the exclusive nature of PSA and may be additive molecule in the dictionary of seminal proteins. Surface plasmon resonance and lectin immunoassay revealed direct interaction between a newly developed anti-PSA monoclonal antibody (C4E6) and PSA. A lectin based immunoassay is reported here which was achieved with the C4E6 anti-PSA antibody and biotinylated plant lectins. This investigation provides an alternative method to isolate and quantify PSA with altered glycosylation which might be seen in the prostate cancer and developing a lectin based immunoassay to detect PSA in serum of prostate cancer patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Intravital lectin perfusion analysis of vascular permeability in human micro- and macro- blood vessels.

    PubMed

    Debbage, P L; Sölder, E; Seidl, S; Hutzler, P; Hugl, B; Ofner, D; Kreczy, A

    2001-10-01

    We previously applied intravital lectin perfusion in mouse models to elucidate mechanisms underlying vascular permeability. The present work transfers this technique to human models, analysing vascular permeability in macro- and microvessels. Human vascular endothelial surface carbohydrate biochemistry differs significantly from its murine counterpart, lacking alpha-galactosyl epitopes and expressing the L-fucose moiety in the glycocalyx; the poly-N-lactosamine glycan backbone is common to all mammals. We examined extensively lectin binding specificities in sections and in vivo, and then applied the poly-N-lactosamine-specific lectin LEA and the L-fucose-specific lectin UEA-I in human intravital perfusions. Transendothelial transport differed in macrovessels and microvessels. In microvessels of adult human fat tissue, rectal wall and rectal carcinomas, slow transendothelial transport by vesicles was followed by significant retention at the subendothelial basement membrane; paracellular passage was not observed. Passage time exceeded 1 h. Thus we found barrier mechanisms resembling those we described previously in murine tissues. In both adult and fetal macrovessels, the vena saphena magna and the umbilical vein, respectively, rapid passage across the endothelial lining was observed, the tracer localising completely in the subendothelial tissues within 15 min; vesicular transport was more rapid than in microvessels, and retention at the subendothelial basement membrane briefer.

  5. The effect of the lectin from Cherax quadricarinatus on its granular hemocytes.

    PubMed

    Sánchez-Salgado, José Luis; Pereyra, Mohamed Alí; Agundis, Concepción; Vivanco-Rojas, Oscar; Rosales, Carlos; Pascual, Cristina; Alpuche-Osorno, Juan José; Zenteno, Edgar

    2018-06-01

    In crustaceans, lectins and hemocytes of the innate immune system provide the first line of defense. Although evidence points to the potential role of lectins in regulating hemocyte activity, the processes underlying the lectin activation have not been evaluated. In the present study, the receptor for CqL, a humoral lectin from Cherax quadricarinatus specific for galactose/sialic acid, was identified in a granular subset of hemocytes. The CqL receptor (CqLR) is a 490-kDa glycoprotein, composed of four identical 120-kDa subunits. As shown by immunohistochemistry, CqL at 7.5 μg/mL as optimal dose, after 2 min, induced, specifically on granular hemocytes, increased phosphorylation of serine (152%), threonine (192%), and tyrosine (242%) as compared with non-treated hemocytes; moreover, CqL induced increased generation of reactive oxygen species (ROS). Specific kinase inhibitors showed inhibition (P < 0.001) of ROS production induced by CqL. These results strongly suggest that CqL actively participated in the generation of ROS through kinases induced by a CqLR in a subset of granular hemocytes of the crayfish C. quadricarinatus. The results provide strong evidence that CqL activates, through specific granular hemocytes, receptors that modulate cellular functions in C. quadricarinatus. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

    PubMed

    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.

  7. A Novel Fucose-binding Lectin from Photorhabdus luminescens (PLL) with an Unusual Heptabladed β-Propeller Tetrameric Structure*

    PubMed Central

    Kumar, Atul; Sýkorová, Petra; Demo, Gabriel; Dobeš, Pavel; Hyršl, Pavel

    2016-01-01

    Photorhabdus luminescens is known for its symbiosis with the entomopathogenic nematode Heterorhabditis bacteriophora and its pathogenicity toward insect larvae. A hypothetical protein from P. luminescens was identified, purified from the native source, and characterized as an l-fucose-binding lectin, named P. luminescens lectin (PLL). Glycan array and biochemical characterization data revealed PLL to be specific toward l-fucose and the disaccharide glycan 3,6-O-Me2-Glcβ1–4(2,3-O-Me2)Rhaα-O-(p-C6H4)-OCH2CH2NH2. PLL was discovered to be a homotetramer with an intersubunit disulfide bridge. The crystal structures of native and recombinant PLL revealed a seven-bladed β-propeller fold creating seven putative fucose-binding sites per monomer. The crystal structure of the recombinant PLL·l-fucose complex confirmed that at least three sites were fucose-binding. Moreover, the crystal structures indicated that some of the other sites are masked either by the tetrameric nature of the lectin or by incorporation of the C terminus of the lectin into one of these sites. PLL exhibited an ability to bind to insect hemocytes and the cuticular surface of a nematode, H. bacteriophora. PMID:27758853

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

    PubMed

    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.

  9. Immobilization of sugars in supermacroporous cryogels for the purification of lectins by affinity chromatography.

    PubMed

    Gonçalves, Gabriel Ramos Ferreira; Gandolfi, Olga Reinert Ramos; Santos, Leandro Soares; Bonomo, Renata Cristina Ferreira; Veloso, Cristiane Martins; Veríssimo, Lizzy Ayra Alcântara; Fontan, Rafael da Costa Ilhéu

    2017-11-15

    Lectins are glycoproteins that bind to carbohydrates or glycoconjugates by specific interactions. The specificity of lectins to various carbohydrates is a determinant factor in the choice of ligand for the chromatographic matrix when using chromatography as a lectin purification technique. In this work, the immobilization of three different aminated carbohydrates on the surface of macroporous polymeric cryogels was evaluated. Carbohydrates were immobilized on cryogel surfaces via the glutaraldehyde method to create spacer arms, reducing steric hindrance. The immobilized N-acetyl-d-glucosamine and N-acetyl-d-mannosamine concentrations contained approximately 130mg of carbohydrate/g dehydrated cryogel, while the N-acetyl-d-galactosamine contained 105mg of carbohydrate/g dehydrated cryogel. Scanning electron microscopy showed that the physical structure and porosity of the chromatographic columns were not affected by the immobilization process, maintaining an elevated hydration capacity and the macroporous structure of the cryogels. Adsorption of concanavalin A on cryogels functionalized with N-acetyl-d-glucosamine (cryo-d-GlcNAc) was tested, as well as its reuse capability. After 5 cycles of use, cryo-d-GlcNAc was shown to be stable, with an adsorptive capacity of around 50mg/g. Carbohydrate immobilization in polyacrylamide cryogels was satisfactory, with promise for applications in lectin purification processes. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Expression of soybean lectin in transgenic tobacco results in enhanced resistance to pathogens and pests.

    PubMed

    Guo, Peipei; Wang, Yu; Zhou, Xiaohui; Xie, Yongli; Wu, Huijun; Gao, Xuewen

    2013-10-01

    Lectins are proteins of non-immune origin that specifically interact with carbohydrates, known to play important roles in the defense system of plants. In this study, in order to study the function of a new soybean lectin (SBL), the corresponding encoding gene lec-s was introduced into tobacco plants via Agrobacterium-mediated transformation. Southern blot analyses had revealed that the lec-s gene was stable integrated into the chromosome of the tobacco. The results of the reverse transcription polymerase chain reaction (RT-PCR) also indicated that the lec-s gene in the transgenic tobacco plants could be expressed under the control of the constitutive CaMV35S promoter. Evaluation agronomic of the performance had showed that the transgenic plants could resist to the infection of Phytophthora nicotianae. Insect bioassays using detached leaves from transgenic tobacco plants demonstrated that the ectopically expressed SBL significantly (P.0.05) reduced the weight gain of larvae of the beet armyworm (Spodoptera exigua). Further on, the lectins retarded the development of the larvae and their metamorphosis. These findings suggest that soybean lectins have potential as a protective agent against pathogens and insect pests through a transgenic approach. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  11. Tobacco plants transformed with the bean. alpha. ai gene express an inhibitor of insect. alpha. -amylase in their seeds. [Nicotiana tabacum; Tenebrio molitor

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

    Altabella, T.; Chrispeels, M.J.

    Bean (Phaseolus vulgaris L.) seeds contain a putative plant defense protein that inhibits insect and mammalian but not plant {alpha}-amylases. We recently presented strong circumstantial evidence that this {alpha}-amylase inhibitor ({alpha}Al) is encoded by an already-identified lectin gene whose product is referred to as lectin-like-protein (LLP). We have now made a chimeric gene consisting of the coding sequence of the lectin gene that encodes LLP and the 5{prime} and 3{prime} flanking sequences of the lectin gene that encodes phytohemagglutinin-L. When this chimeric gene was expressed in transgenic tobacco (Nicotiana tabacum), we observed in the seeds a series of polypeptides (M{submore » r} 10,000-18,000) that cross-react with antibodies to the bean {alpha}-amylase inhibitor. Most of these polypeptides bind to a pig pancreas {alpha}-amylase affinity column. An extract of the seeds of the transformed tobacco plants inhibits pig pancreas {alpha}-amylase activity as well as the {alpha}-amylase present in the midgut of Tenebrio molitor. We suggest that introduction of this lectin gene (to be called {alpha}ai) into other leguminous plants may be a strategy to protect the seeds from the seed-eating larvae of Coleoptera.« less

  12. Fungal lectin MpL enables entry of protein drugs into cancer cells and their subcellular targeting

    PubMed Central

    Kos, Janko; Sabotič, Jerica

    2017-01-01

    Lectins have been recognized as promising carrier molecules for targeted drug delivery. They specifically bind carbohydrate moieties on cell membranes and trigger cell internalization. Fungal lectin MpL (Macrolepiota procera lectin) does not provoke cancer cell cytotoxicity but is able to bind aminopeptidase N (CD13) and integrin α3β1, two glycoproteins that are overexpressed on the membrane of tumor cells. Upon binding, MpL is endocytosed in a clathrin-dependent manner and accumulates initially in the Golgi apparatus and, finally, in the lysosomes. For effective binding and internalization a functional binding site on the α-repeat is needed. To test the potential of MpL as a carrier for delivering protein drugs to cancer cells we constructed fusion proteins consisting of MpL and the cysteine peptidase inhibitors cystatin C and clitocypin. The fused proteins followed the same endocytic route as the unlinked MpL. Peptidase inhibitor-MpL fusions impaired both the intracellular degradation of extracellular matrix and the invasiveness of cancer cells. MpL is thus shown in vitro to be a lectin that can enable protein drugs to enter cancer cells, enhance their internalization and sort them to lysosomes and the Golgi apparatus. PMID:28460472

  13. Capture of cell culture-derived influenza virus by lectins: strain independent, but host cell dependent.

    PubMed

    Opitz, Lars; Zimmermann, Anke; Lehmann, Sylvia; Genzel, Yvonne; Lübben, Holger; Reichl, Udo; Wolff, Michael W

    2008-12-01

    Strategies to control influenza outbreaks are focused mainly on prophylactic vaccination. Human influenza vaccines are trivalent blends of different virus subtypes. Therefore and due to frequent antigenic drifts, strain independent manufacturing processes are required for vaccine production. This study verifies the strain independency of a capture method based on Euonymus europaeus lectin-affinity chromatography (EEL-AC) for downstream processing of influenza viruses under various culture conditions propagated in MDCK cells. A comprehensive lectin binding screening was conducted for two influenza virus types from the season 2007/2008 (A/Wisconsin/67/2005, B/Malaysia/2506/2004) including a comparison of virus-lectin interaction by surface plasmon resonance technology. EEL-AC resulted in a reproducible high product recovery rate and a high degree of contaminant removal in the case of both MDCK cell-derived influenza virus types demonstrating clearly the general applicability of EEL-AC. In addition, host cell dependency of EEL-AC was studied with two industrial relevant cell lines: Vero and MDCK cells. However, the choice of the host cell lines is known to lead to different product glycosylation profiles. Hence, altered lectin specificities have been observed between the two cell lines, requiring process adaptations between different influenza vaccine production systems.

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

    PubMed Central

    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. Glycophenotype evaluation in cutaneous tumors using lectins labeled with acridinium ester.

    PubMed

    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.

  16. Engineering the Pseudomonas aeruginosa II lectin: designing mutants with changed affinity and specificity

    NASA Astrophysics Data System (ADS)

    Kříž, Zdeněk; Adam, Jan; Mrázková, Jana; Zotos, Petros; Chatzipavlou, Thomais; Wimmerová, Michaela; Koča, Jaroslav

    2014-09-01

    This article focuses on designing mutations of the PA-IIL lectin from Pseudomonas aeruginosa that lead to change in specificity. Following the previous results revealing the importance of the amino acid triad 22-23-24 (so-called specificity-binding loop), saturation in silico mutagenesis was performed, with the intent of finding mutations that increase the lectin's affinity and modify its specificity. For that purpose, a combination of docking, molecular dynamics and binding free energy calculation was used. The combination of methods revealed mutations that changed the performance of the wild-type lectin and its mutants to their preferred partners. The mutation at position 22 resulted in 85 % in inactivation of the binding site, and the mutation at 23 did not have strong effects thanks to the side chain being pointed away from the binding site. Molecular dynamics simulations followed by binding free energy calculation were performed on mutants with promising results from docking, and also at those where the amino acid at position 24 was replaced for bulkier or longer polar chain. The key mutants were also prepared in vitro and their binding properties determined by isothermal titration calorimetry. Combination of the used methods proved to be able to predict changes in the lectin performance and helped in explaining the data observed experimentally.

  17. A shrimp C-type lectin inhibits proliferation of the hemolymph microbiota by maintaining the expression of antimicrobial peptides.

    PubMed

    Wang, Xian-Wei; Xu, Ji-Dong; Zhao, Xiao-Fan; Vasta, Gerardo Raul; Wang, Jin-Xing

    2014-04-25

    Some aquatic invertebrates such as shrimp contain low albeit stable numbers of bacteria in the circulating hemolymph. The proliferation of this hemolymph microbiota in such a nutrient-rich environment is tightly controlled in healthy animals, but the mechanisms responsible had remained elusive. In the present study, we report a C-type lectin (MjHeCL) from the kuruma shrimp (Marsupenaeus japonicus) that participates in restraining the hemolymph microbiota. Although the expression of MjHeCL did not seem to be modulated by bacterial challenge, the down-regulation of its expression by RNA interference led to proliferation of the hemolymph microbiota, ultimately resulting in shrimp death. This phenotype was rescued by the injection of recombinant MjHeCL, which restored the healthy status of the knockdown shrimp. A mechanistic analysis revealed that MjHeCL inhibited bacterial proliferation by modulating the expression of antimicrobial peptides. The key function of MjHeCL in the shrimp immune homeostasis might be related to its broader recognition spectrum of the hemolymph microbiota components than other lectins. Our study demonstrates the role of MjHeCL in maintaining the healthy status of shrimp and provides new insight into the biological significance of C-type lectins, a diversified and abundant lectin family in invertebrate species.

  18. The sequence and structure of snake gourd (Trichosanthes anguina) seed lectin, a three-chain nontoxic homologue of type II RIPs.

    PubMed

    Sharma, Alok; Pohlentz, Gottfried; Bobbili, Kishore Babu; Jeyaprakash, A Arockia; Chandran, Thyageshwar; Mormann, Michael; Swamy, Musti J; Vijayan, M

    2013-08-01

    The sequence and structure of snake gourd seed lectin (SGSL), a nontoxic homologue of type II ribosome-inactivating proteins (RIPs), have been determined by mass spectrometry and X-ray crystallography, respectively. As in type II RIPs, the molecule consists of a lectin chain made up of two β-trefoil domains. The catalytic chain, which is connected through a disulfide bridge to the lectin chain in type II RIPs, is cleaved into two in SGSL. However, the integrity of the three-dimensional structure of the catalytic component of the molecule is preserved. This is the first time that a three-chain RIP or RIP homologue has been observed. A thorough examination of the sequence and structure of the protein and of its interactions with the bound methyl-α-galactose indicate that the nontoxicity of SGSL results from a combination of changes in the catalytic and the carbohydrate-binding sites. Detailed analyses of the sequences of type II RIPs of known structure and their homologues with unknown structure provide valuable insights into the evolution of this class of proteins. They also indicate some variability in carbohydrate-binding sites, which appears to contribute to the different levels of toxicity exhibited by lectins from various sources.

  19. Use of lectins to in situ visualize glycoconjugates of extracellular polymeric substances in acidophilic archaeal biofilms

    PubMed Central

    Zhang, R Y; Neu, T R; Bellenberg, S; Kuhlicke, U; Sand, W; Vera, M

    2015-01-01

    Biofilm formation and the production of extracellular polymeric substances (EPS) by meso- and thermoacidophilic metal-oxidizing archaea on relevant substrates have been studied to a limited extent. In order to investigate glycoconjugates, a major part of the EPS, during biofilm formation/bioleaching by archaea on pyrite, a screening with 75 commercially available lectins by fluorescence lectin-binding analysis (FLBA) has been performed. Three representative archaeal species, Ferroplasma acidiphilum DSM 28986, Sulfolobus metallicus DSM 6482T and a novel isolate Acidianus sp. DSM 29099 were used. In addition, Acidianus sp. DSM 29099 biofilms on elemental sulfur were studied. The results of FLBA indicate (i) 22 lectins bound to archaeal biofilms on pyrite and 21 lectins were binding to Acidianus sp. DSM 29099 biofilms on elemental sulfur; (ii) major binding patterns, e.g. tightly bound EPS and loosely bound EPS, were detected on both substrates; (iii) the three archaeal species produced various EPS glycoconjugates on pyrite surfaces. Additionally, the substratum induced different EPS glycoconjugates and biofilm structures of cells of Acidianus sp. DSM 29099. Our data provide new insights into interactions between acidophilic archaea on relevant surfaces and also indicate that FLBA is a valuable tool for in situ investigations on archaeal biofilms. PMID:25488256

  20. Cytochemical analysis of alkaline phosphatase and esterase activities and of lectin-binding and anionic sites in rat and mouse Peyer's patch M cells.

    PubMed

    Owen, R L; Bhalla, D K

    1983-10-01

    M cells in Peyer's patch follicle epithelium endocytose and transport luminal materials to intraepithelial lymphocytes. We examined (1) enzymatic characteristics of the epithelium covering mouse and rat Peyer's patches by using cytochemical techniques, (2) distribution of lectin-binding sites by peroxidase-labeled lectins, and (3) anionic site distribution by using cationized ferritin to develop a profile of M cell surface properties. Alkaline phosphatase activity resulted in deposits of dense reaction product over follicle surfaces but was markedly reduced over M cells, unlike esterase which formed equivalent or greater product over M cells. Concanavalin A, ricinus communis agglutinin, wheat germ agglutinin and peanut agglutinin reacted equally with M cells and with surrounding enterocytes over follicle surfaces. Cationized ferritin distributed in a random fashion along microvillus membranes of both M cells and enterocytes, indicating equivalent anionic site distribution. Staining for alkaline phosphatase activity provides a new approach for distinguishing M cells from enterocytes at the light microscopic level. Identical binding of lectins indicates that M cells and enterocytes share common glycoconjugates even though molecular groupings may differ. Lectin binding and anionic charge similarities of M cells and enterocytes may facilitate antigen sampling by M cells of particles and compounds that adhere to intestinal surfaces in non-Peyer's patch areas.

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

    PubMed

    Biswas, C; Sinha, D; Mandal, C

    2000-01-01

    Achatinin, a 9-O-acetyl sialic acid (9-O-AcSA) binding lectin, has been demonstrated to be synthesized in amoebocytes of Achatina fulica snails. This lectin was affinity-purified from Achatina amoebocytes lysate (AAL); it appeared as a single band on native polyacrylamide gel electrophoresis (PAGE) and showed 16 identical subunits of M.W. 15 kDa on sodium dodecyl sulphate (SDS)-PAGE. It was found to be homologous with an earlier reported lectin, Achatinin-H, derived from hemolymph of A. fulica snails (Sen, G., Mandal, C., 1995. The specificity of the binding site of Achatinin-H, a sialic-acid binding lectin from Achantia fulica. Carbohydr. Res., 268, 115-125). Homology between both lectins was confirmed by their similar electrophoretic mobilities, carbohydrate specificity and cross reactivity on immunodiffusion. Achatinin showed in vitro calcium dependent binding to two 9-O-acetylated sialoglyoconjugates (9-O-AcSG) on lipopolysaccharide (LPS) (Escherichia coli 055: B5) of M.W. 40 kDa and 27.5 kDa, which was abolished following de-O-acetylation. Based on the previously defined narrow sugar specificity of Achatinin towards 9-O-AcSAalpha2-->6GalNAc [Sen, G., Mandal, C., 1995. The specificity of the binding site of Achatinin-H, a sialic-acid binding lectin from Achatina fulica. Carbohydr. Res., 268, 115-125], we conclude that LPS contains this lectinogenic epitope at the terminal sugar moiety. The Achatinin-mediated hemagglutination inhibition of rabbit erythrocytes by LPS further confirmed it. The lectin exhibited bacteriostatic effect on Gram-negative bacteria E. coli, DH5alpha and C600. AAL was earlier reported to undergo coagulation in presence of pg level of LPS (Biswas, C., Mandal, C., 1999. The role of amoebocytes in the endotoxin-mediated coagulation in the innate immunity of Achatina fulica snail, Scand. J. Immunol. 49, 131-138). We now demonstrate that Achatinin participates in LPS-mediated coagulation of AAL as indicated by enhanced release of Achatinin from 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.

  2. Label-free detection of glycoproteins by the lectin biosensor down to attomolar level using gold nanoparticles

    PubMed Central

    Bertok, Tomas; Sediva, Alena; Katrlik, Jaroslav; Gemeiner, Pavol; Mikula, Milan; Nosko, Martin; Tkac, Jan

    2016-01-01

    We present here an ultrasensitive electrochemical biosensor based on a lectin biorecognition capable to detect concentrations of glycoproteins down to attomolar (aM) level by investigation of changes in the charge transfer resistance (Rct) using electrochemical impedance spectroscopy (EIS). On polycrystalline gold modified by an aminoalkanethiol linker layer, gold nanoparticles were attached. A Sambucus nigra agglutinin was covalently immobilised on a mixed self-assembled monolayer formed on gold nanoparticles and finally, the biosensor surface was blocked by poly(vinylalcohol). The lectin biosensor was applied for detection of sialic acid containing glycoproteins fetuin and asialofetuin. Building of a biosensing interface was carefully characterised by a broad range of techniques such as electrochemistry, EIS, atomic force microscopy, scanning electron microscopy and surface plasmon resonance with the best performance of the biosensor achieved by application of HS-(CH2)11-NH2 linker and gold nanoparticles with a diameter of 20 nm. The lectin biosensor responded to an addition of fetuin (8.7% of sialic acid) with sensitivity of (338 ± 11) Ω decade-1 and to asialofetuin (≤ 0.5% of sialic acid) with sensitivity of (109 ± 10) Ω decade-1 with a blank experiment with oxidised asialofetuin (without recognisable sialic acid) revealing sensitivity of detection of (79 ± 13) Ω decade-1. These results suggest the lectin biosensor responded to changes in the glycan amount in a quantitative way with a successful validation by a lectin microarray. Such a biosensor device has a great potential to be employed in early biomedical diagnostics of diseases such as arthritis or cancer, which are connected to aberrant glycosylation of protein biomarkers in biological fluids. PMID:23601864

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

    PubMed Central

    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

  4. Purification and properties of an N-acetylglucosamine-specific lectin from Psathyrella velutina mushroom.

    PubMed

    Kochibe, N; Matta, K L

    1989-01-05

    A lectin in the fruiting bodies of Psathyrella velutina was purified by affinity chromatography on a chitin column and subsequent ion-exchange chromatography. P. velutina lectin (PVL) tends to aggregate irreversibly in buffered saline, but the addition of glycerol (10%, v/v) to lectin solutions was found to prevent aggregate formation. PVL is assumed to occur as a monomer of a polypeptide of Mr = 40,000 as determined by gel filtration and by gel electrophoresis in the presence of sodium dodecyl sulfate. PVL is specific for N-acetylglucosamine (GlcNAc). It was determined by equilibrium dialysis to have four binding sites/polypeptide molecule showing an average intrinsic association constant of K0 = 6.4 x 10(3) M-1 toward this sugar. The binding specificity of the lectin was studied by hemagglutination inhibition assays and by avidin-biotin-mediated enzyme immunoassays using various GlcNAc-containing saccharides. The results indicate that methyl N-acetyl beta-glucosaminide was a slightly better inhibitor than the corresponding alpha-anomer. PVL binds well to oligosaccharides bearing nonreducing terminal beta-GlcNAc linked 1----6 or 1----3 but poorly to those having a 1----4 linkage, such as N-acetylated chito-oligosaccharides. It also binds to the subterminal GlcNAc moiety when it is substituted at the C-6 position but does not interact with the moiety when substituted either at C-3 or C-4. Thus, these results show that PVL is quite different in its binding specificity from other GlcNAc-binding lectins of higher plants since they bind preferentially to beta-GlcNAc in 1----4 linkage and they have a high affinity for chitin oligosaccharides.

  5. Suppression of proliferation and neurite extension of human neuroblastoma SH-SY5Y cells on immobilized Psathyrella velutina lectin.

    PubMed

    Kitamura, Noriaki; Ikekita, Masahiko; Hayakawa, Satoru; Funahashi, Hisayuki; Furukawa, Kiyoshi

    2004-02-01

    Glycoproteins from mammalian brain tissues contain unique N-linked oligosaccharides terminating with beta-N-acetylglucosamine residues. Lectin blot analysis of membrane glycoprotein samples from human neuroblastoma SH-SY5Y cells showed that several protein bands bind to Psathylera velutina lectin (PVL), which interacts with beta-N-acetylglucosamine-terminating oligosaccharides. No lectin positive bands were detected by digestion with jack bean beta-N-acetyl-hexosaminidase or N-glycanase before incubation with the lectin, indicating that the cells contain beta-N-acetylglucosamine-terminating N-linked oligosaccharides. When cells were cultured in dishes with different concentrations of PVL, the cell proliferation was inhibited in a dose-dependent manner. Similarly, the neurite extension, which was stimulated with nerve growth factor, was also inhibited in a manner dependent on the lectin dose. Cell proliferation and neurite extension were recovered by the addition of 10 mM N-acetylglucosamine into the medium. Immunoblot analysis of the activation of mitogen-activated protein (MAP) kinases and protein kinase C revealed that phosphorylation of 42-kDa and 44-kDa MAP kinases and 80-kDa protein kinase C are inhibited when SH-SY5Y cells are cultured in PVL-coated dishes, but are restored by the addition of the haptenic sugar into the medium, indicating that MAP kinase and protein kinase C pathways are inhibited by interaction with immobilized PVL. These results indicate that beta-N-acetylglucosamine-terminating N-linked oligosaccharides expressed on neural cells can induce intracellular signals upon binding to extracellular receptors, and are important for growth regulation of neural cells. Copyright 2003 Wiley-Liss, Inc.

  6. Purification and characterization of a Ca(2+)-dependent novel lectin from Nymphaea nouchali tuber with antiproliferative activities.

    PubMed

    Kabir, Syed Rashel; Zubair, Md Abu; Nurujjaman, Md; Haque, Md Azizul; Hasan, Imtiaj; Islam, Md Farhadul; Hossain, Md Tanvir; Hossain, Md Anowar; Rakib, Md Abdur; Alam, Mohammad Taufiq; Shaha, Ranajit Kumar; Hossain, Md Tofazzal; Kimura, Yoshinobu; Absar, Nurul

    2011-12-01

    A lectin (termed NNTL) was purified from the extracts of Nymphaea nouchali tuber followed by anion-exchange chromatography on DEAE-cellulose, hydrophobic chromatography on HiTrap Phenyl HP and by repeated anion-exchange chromatography on HiTrap Q FF column. The molecular mass of the purified lectin was 27.0 ± 1.0 kDa, as estimated by SDS/PAGE both in the presence and in the absence of 2-mercaptoethanol. NNTL was an o-nitrophenyl β-D-galactopyranoside sugar-specific lectin that agglutinated rat, chicken and different groups of human blood cells and exhibited high agglutination activity over the pH range 5-9 and temperatures of 30-60 °C. The N-terminal sequence of NNTL did not show sequence similarity with any other lectin and the amino acid analysis revealed that NNTL was rich in leucine, methionine and glycine residues. NNTL was a glycoprotein containing 8% neutral sugar and showed toxicity against brine shrimp nauplii with an LC(50) value of 120 ± 29 μg/ml and exerted strong agglutination activity against four pathogenic bacteria (Bacillus subtilis, Sarcina lutea, Shigella shiga and Shigella sonnei). In addition, antiproliferative activity of this lectin against EAC (Ehrlich ascites carcinoma) cells showed 56% and 76% inhibition in vivo in mice at 1.5 and 3 mg·kg(-1)·day(-1) respectively. NNTL was a divalent ion-dependent glycoprotein, which lost its activity markedly in the presence of denaturants. Furthermore, measurement of fluorescence spectra in the presence and absence of urea and CaCl(2) indicated the requirement of Ca(2+) for the stability of NNTL. © The Authors Journal compilation © 2011 Biochemical Society

  7. A novel recombinantly produced banana lectin isoform is a valuable tool for glycoproteomics and a potent modulator of the proliferation response in CD3+, CD4+, and CD8+ populations of human PBMCs.

    PubMed

    Gavrovic-Jankulovic, Marija; Poulsen, Knud; Brckalo, Tamara; Bobic, Sonja; Lindner, Buko; Petersen, Arnd

    2008-01-01

    Lectins as carbohydrate-binding proteins have been employed in various biological assays for the detection and characterization of glycan structures on glycoproteins, including clinical biomarkers in disease states. A mannose-specific banana lectin (BanLec) is unique in its specificity for internal alpha1,3 linkages as well as beta1,3 linkages at the reducing termini. The immunomodulatory potential of natural BanLec was recognized by a strong immunoglobulin G4 antibody response and T cell mitogen activity in humans. To explore its applicability in glycoproteomics and its modulatory potential, the gene of banana lectin was cloned, sequenced and a recombinant protein was produced in Escherichia coli. The obtained cDNA revealed a novel banana lectin isoform, with an open reading frame of 426 nucleotides, encoding a cytoplasmatic protein of 141 amino acids. The molecular mass of rBanLec determined by ESI FT-MS and N-terminal sequencing confirmed the cDNA at the protein level. The specificity of rBanLec for detection glycan structures was the same as for natural BanLec as examined with five protein extracts rich in glycoprotein content, as well as with horseradish peroxidase glycoprotein. Besides, the immunomodulatory potential of rBanLec and nBanLec were comparable as assessed by an inhibition assay and a human T cell proliferation assay where they induced a strong proliferation response in CD3+, CD4+, and CD8+ populations of human PBMCs. This recombinant BanLec is a useful reagent for glycoproteomics and lectin microarrays, with a potential for modulation of the immune response.

  8. The adhesion of Pseudomonas aeruginosa to high molecular weight human tear film species corresponds to glycoproteins reactive with Sambucus nigra lectin.

    PubMed

    Aristoteli, Lina Panayiota; Willcox, Mark D P

    2006-11-01

    Pseudomonas aeruginosa is a pathogen gaining prevalence in contact lens-related corneal ulcers. Tear outflow protects the ocular surface, where high molecular weight tear glycoproteins bind bacteria for removal from the eye. The purpose of the present study was to identify glycoproteins in human tears involved in the adhesion of ocular P. aeruginosa isolates. Basal human tears were applied to a bacterial adhesion assay involving electrophoretic separation of tear components, transfer to nitrocellulose and incubation with biotin-labelled bacteria. Glycoproteins were further characterised using lectin profiling. The results showed large-dimension agarose gels were imperative for the detection of at least four glycoproteins with a migration >200 kDa, including species not previously identified. P. aeruginosa 6294 preferentially bound to a well-defined glycoprotein near the origin of the gel that, unlike other glycoproteins >200 kDa, reacted with Sambucus nigra lectin (sialic acid alpha2-6) but not WGA lectin (N-acetylglucosamine, sialic acid alpha2-3). Adhesion did not involve free biotin label or hydrophobic interactions. Also, the pre-incubation of separated tear glycoproteins with S. nigra lectin increased subsequent adhesion of 6294 to this tear glycoprotein. The less virulent Paer1 strain showed diffuse adhesion in the S. nigra-reactive region at the gel origin. In conclusion, an overlay adhesion assay was developed that identified slow-migrating sialylated glycoprotein species in human tears preferentially bound by P. aeruginosa ocular strains, and S. nigra lectin seemed to enhance the interaction. The study provides a basis for direct investigation of bacterial adhesion to glycoproteins with an apparent migration >200 kDa in tear fluid.

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

    PubMed

    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.

  10. Urtica dioica agglutinin. A superantigenic lectin from stinging nettle rhizome.

    PubMed

    Galelli, A; Truffa-Bachi, P

    1993-08-15

    Urtica dioica agglutinin (UDA) is an unusual plant lectin that differs from all other known plant lectins with respect to its molecular structure and its extremely low specific agglutination activity. We recently reported that this small lectin (8.5 kDa) is a T cell mitogen distinguishable from classical T cell lectin mitogens by its ability to discriminate a particular population of CD4+ and CD8+ T cells as well as its capacity to induce an original pattern of T cell activation and cytokine production. The mechanism by which UDA activates T cells was investigated and compared with the conventional T cell mitogen Con A and the known superantigen staphylococcal enterotoxin B. Our data show that T cell proliferation induced by UDA is strictly dependent on AC expressing MHC class II molecules but is not MHC restricted. This proliferation can be partially inhibited by anti-I-A or anti-I-E mAb and completely blocked by a mAb recognizing monomorphic determinants on the Ia molecule. UDA indeed binds to specific carbohydrate structures present on class II molecules. UDA-induced T cell stimulation is dependent on TCR recognition of the unprocessed intact molecule in association with various Ia molecules. T cell response to UDA is clonally expressed and correlates with particular TCR V beta gene families usage. This stimulation leads to a sixfold enrichment of V beta 8.3+ T cells within 3 days. Therefore, UDA appears to use the same molecular mechanism as structurally unrelated bacterial or retroviral superantigens and we propose that this lectin is a superantigen. UDA, which is not a pathogenicity factor, could provide a useful probe for the analysis of T cell activation by superantigens.

  11. Lectin array and glycogene expression analyses of ovarian cancer cell line A2780 and its cisplatin-resistant derivate cell line A2780-cp.

    PubMed

    Zhao, Ran; Qin, Wenjun; Qin, Ruihuan; Han, Jing; Li, Can; Wang, Yisheng; Xu, Congjian

    2017-01-01

    Ovarian cancer is one of the most lethal gynecological malignancies, in which platinum resistance is a common cause of its relapse and death. Glycosylation has been reported to be involved in drug resistance, and glycomic analyses of ovarian cancer may improve our understanding of the mechanisms underlying cancer cell drug resistance and provide potential biomarkers and therapeutic targets. The serous ovarian cancer cell line A2780 and its platinum-resistant counterpart A2780-cp were used in this study. We performed a lectin array analysis to compare the glycosylation patterns of the two cell lines, a gene expression array was employed to probe the differences in glycogenes. Furthermore, the results were verified by lectin blots. A2780-cp cell exhibited stronger intensities of Lens culinaris (LCA) Canavalia ensiformis (ConA), and Lycopersicon esculentum (LEL) and weaker intensities of Sambucus nigra (SNA) lectins. The gene expression array analysis revealed increased expression of Fut8, B3gnt4, B3gnt5, B4galt2 and decreased expression of Fut1 and ST6GalNAc 6 expression were evident in the A2780-cp cells. The lectin blot confirmed the differences in LCA, ConA, SNA and LEL between the A2780 and A2780-cp cells. The combination of the lectin and gene expression analyses showed that the levels of core fucosylation and poly-LacNAc were increased in the A2780-cp cells and the levels of Fuc α1-2(gal β1-4) GlcNAc and α2-6-linked sialic structures were decreased in the A2780-cp cells. These glycans represent potential biomarkers and might be involved in the mechanism of drug resistance in ovarian cancer.

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

    PubMed

    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.

  13. Enhanced hydrogen peroxide release from macrophages stimulated with streptococcal preparation OK-432.

    PubMed Central

    Saito, H; Tomioka, H

    1979-01-01

    Wheat germ lectin was found to be a potent triggering agent for hydrogen peroxide release from mouse peritoneal macrophages. Macrophages stimulated by intraperitoneal injection of OK-432, a lyophilized attenuated streptococcal preparation, were highly responsive to wheat germ lectin. PMID:546795

  14. Sugar residues content and distribution in atrophic and hyperplastic postmenopausal human endometrium: lectin histochemistry.

    PubMed

    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.

  15. Regional differences in lectin binding patterns of vestibular hair cells

    NASA Technical Reports Server (NTRS)

    Baird, Richard A.; Schuff, N. R.; Bancroft, J.

    1994-01-01

    Surface glycoconjugates of hair cells and supporting cells in the vestibular endorgans of the bullfrog were identified using biotinylated lectins with different carbohydrate specificities. Lectin binding in hair cells was consistent with the presence of glucose and mannose (CON A), galactose (RCA-I), N-acetylgalactosamine (VVA), but not fucose (UEA-I) residues. Hair cells in the bullfrog sacculus, unlike those in the utriculus and semicircular canals, did not stain for N-acetylglucosamine (WGA) or N-acetylgalactosamine (VVA). By contrast, WGA and, to a lesser extent, VVA, differentially stained utricular and semicircular canal hair cells, labeling hair cells located in peripheral, but not central, regions. In mammals, WGA uniformly labeled Type 1 hair cells while labeling, as in the bullfrog, Type 2 hair cells only in peripheral regions. These regional variations were retained after enzymatic digestion. We conclude that vestibular hair cells differ in their surface glycoconjugates and that differences in lectin binding patterns can be used to identify hair cell types and to infer the epithelial origin of isolated vestibular hair cells.

  16. Single molecular dynamic interactions between glycophorin A and lectin as probed by atomic force microscopy.

    PubMed

    Yan, Chao; Yersin, Alexandre; Afrin, Rehana; Sekiguchi, Hiroshi; Ikai, Atsushi

    2009-09-01

    Glycophorin A (GpA) is one of the most abundant transmembrane proteins in human erythrocytes and its interaction with lectins has been studied as model systems for erythrocyte related biological processes. We performed a force measurement study using the force mode of atomic force microscopy (AFM) to investigate the single molecular level biophysical mechanisms involved in GpA-lectin interactions. GpA was mounted on a mica surface or natively presented on the erythrocyte membrane and probed with an AFM tip coated with the monomeric but multivalent Psathyrella velutina lectin (PVL) through covalent crosslinkers. A dynamic force spectroscopy study revealed similar interaction properties in both cases, with the unbinding force centering around 60 pN with a weak loading rate dependence. Hence we identified the presence of one energy barrier in the unbinding process. Force profile analysis showed that more than 70% of GpAs are free of cytoskeletal associations in agreement with previous reports.

  17. Glycodendritic structures based on Boltorn hyperbranched polymers and their interactions with Lens culinaris lectin.

    PubMed

    Arce, Eva; Nieto, Pedro M; Díaz, Vicente; Castro, Rossana García; Bernad, Antonio; Rojo, Javier

    2003-01-01

    Multivalent scaffolds bearing carbohydrates have been prepared to mediate biological processes where carbohydrates are involved. These systems consist of dendritic structures based on Boltorn H20 and H30 hyperbranched polymers to which carbohydrates are linked through a convenient spacer. Mannose has been chosen as a sugar unit to test the viability of this strategy. These glycodendritic compounds have been prepared in a few steps with good yields, showing a high solubility in physiological media and low toxicity. The binding of these dendritic polymers to the mannose-binding lectin Lens culinaris (LCA) was studied using STD-NMR experiments and quantitative precipitation assays. The results demonstrate the existence of a clear interaction between the mannose derivative systems and the Lens lectin where the dendritic scaffold does not have an important role in mannose binding but supplies the necessary multivalence for lectin cluster formation. These glycodendritic structures are able to interact with a receptor, and therefore they can be considered as promising tools for biological studies.

  18. Molecular profile of the unique species of traditional Chinese medicine, Chinese seahorse (Hippocampus kuda Bleeker).

    PubMed

    Zhang, Ning; Xu, Bin; Mou, Chunyan; Yang, Wenli; Wei, Jianwen; Lu, Liang; Zhu, Junjie; Du, Jingchun; Wu, Xiaokun; Ye, Lanting; Fu, Zhiyan; Lu, Yang; Lin, Jianghai; Sun, Zizi; Su, Jing; Dong, Meiling; Xu, Anlong

    2003-08-28

    A cDNA library of male Chinese seahorse (Hippocampus kuda Bleeker) was constructed to investigate the molecular profile of seahorse as one of the most famous traditional Chinese medicine materials, and to reveal immunological and physiological mechanisms of seahorse as one of the most primitive vertebrates at molecular level. A total of 3372 expressed sequence tags (ESTs) consisting of 1911 unique genes (345 clusters and 1566 singletons) were examined in the present study. Identification of the genes related to immune system, paternal brooding and physiological regulation provides not only valuable insights into the molecular mechanism of immune system in teleost fish but also plausible explanations for pharmacological activities of Chinese seahorse. Furthermore, the occurrence of high prevalent C-type lectins suggested that a lectin-complement pathway might exert a more dominant function in the innate immune system of teleost than mammal. Carbohydrate recognition domain (CRD) without a collagen-like region in the lectins of seahorse was likely an ancient characteristic of lectins similar to invertebrates.

  19. Engineering a therapeutic lectin by uncoupling mitogenicity from antiviral activity.

    PubMed

    Swanson, Michael D; Boudreaux, Daniel M; Salmon, Loïc; Chugh, Jeetender; Winter, Harry C; Meagher, Jennifer L; André, Sabine; Murphy, Paul V; Oscarson, Stefan; Roy, René; King, Steven; Kaplan, Mark H; Goldstein, Irwin J; Tarbet, E Bart; Hurst, Brett L; Smee, Donald F; de la Fuente, Cynthia; Hoffmann, Hans-Heinrich; Xue, Yi; Rice, Charles M; Schols, Dominique; Garcia, J Victor; Stuckey, Jeanne A; Gabius, Hans-Joachim; Al-Hashimi, Hashim M; Markovitz, David M

    2015-10-22

    A key effector route of the Sugar Code involves lectins that exert crucial regulatory controls by targeting distinct cellular glycans. We demonstrate that a single amino-acid substitution in a banana lectin, replacing histidine 84 with a threonine, significantly reduces its mitogenicity, while preserving its broad-spectrum antiviral potency. X-ray crystallography, NMR spectroscopy, and glycocluster assays reveal that loss of mitogenicity is strongly correlated with loss of pi-pi stacking between aromatic amino acids H84 and Y83, which removes a wall separating two carbohydrate binding sites, thus diminishing multivalent interactions. On the other hand, monovalent interactions and antiviral activity are preserved by retaining other wild-type conformational features and possibly through unique contacts involving the T84 side chain. Through such fine-tuning, target selection and downstream effects of a lectin can be modulated so as to knock down one activity, while preserving another, thus providing tools for therapeutics and for understanding the Sugar Code. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. The bean. alpha. -amylase inhibitor is encoded by a lectin gene

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

    Moreno, J.; Altabella, T.; Chrispeels, M.J.

    The common bean, Phaseolus vulgaris, contains an inhibitor of insect and mammalian {alpha}-amylases that does not inhibit plant {alpha}-amylase. This inhibitor functions as an anti-feedant or seed-defense protein. We purified this inhibitor by affinity chromatography and found that it consists of a series of glycoforms of two polypeptides (Mr 14,000-19,000). Partial amino acid sequencing was carried out, and the sequences obtained are identical with portions of the derived amino acid sequence of a lectin-like gene. This lectin gene encodes a polypeptide of MW 28,000, and the primary in vitro translation product identified by antibodies to the {alpha}-amylase inhibitor has themore » same size. Co- and posttranslational processing of this polypeptide results in glycosylated polypeptides of 14-19 kDa. Our interpretation of these results is that the bean lectins constitute a gene family that encodes diverse plant defense proteins, including phytohemagglutinin, arcelin and {alpha}-amylase inhibitor.« less

  1. Labeling of lectin receptors during the cell cycle.

    PubMed

    Garrido, J

    1976-12-01

    Labeling of lectin receptors during the cell cycle. (Localizabión de receptores para lectinas durante el ciclo celular). Arch. Biol. Med. Exper. 10: 100-104, 1976. The topographic distribution of specific cell surface receptors for concanavalin A and wheat germ agglutinin was studied by ultrastructural labeling in the course of the cell cycle. C12TSV5 cells were synchronized by double thymidine block or mechanical selection (shakeoff). They were labeled by means of lectin-peroxidase techniques while in G1 S, G2 and M phases of the cycle. The results obtained were similar for both lectins employed. Interphase cells (G1 S, G2) present a stlihtly discontinous labeling pattern that is similar to the one observed on unsynchronized cells of the same line. Cells in mitosis, on the contrary, present a highly discontinous distribution of reaction product. This pattern disappears after the cells enters G1 and is not present on mitotic cells fixed in aldehyde prior to labeling.

  2. Engineering a Therapeutic Lectin by Uncoupling Mitogenicity from Antiviral Activity

    PubMed Central

    Swanson, Michael D.; Boudreaux, Daniel M.; Salmon, Loïc; Chugh, Jeetender; Winter, Harry C.; Meagher, Jennifer L.; André, Sabine; Murphy, Paul V.; Oscarson, Stefan; Roy, René; King, Steven; Kaplan, Mark H.; Goldstein, Irwin J.; Tarbet, E. Bart; Hurst, Brett L.; Smee, Donald F.; de la Fuente, Cynthia; Hoffmann, Hans-Heinrich; Xue, Yi; Rice, Charles M.; Schols, Dominique; Garcia, J. Victor; Stuckey, Jeanne A.; Gabius, Hans-Joachim; Al-Hashimi, Hashim M.; Markovitz, David M.

    2015-01-01

    Summary A key effector route of the Sugar Code involves lectins that exert crucial regulatory controls by targeting distinct cellular glycans. We demonstrate that a single amino acid substitution in a banana lectin, replacing histidine 84 with a threonine, significantly reduces its mitogenicity while preserving its broad-spectrum antiviral potency. X-ray crystallography, NMR spectroscopy, and glycocluster assays reveal that loss of mitogenicity is strongly correlated with loss of pi-pi stacking between aromatic amino acids H84 and Y83, which removes a wall separating two carbohydrate binding sites, thus diminishing multivalent interactions. On the other hand, monovalent interactions and antiviral activity are preserved by retaining other wild-type conformational features and possibly through unique contacts involving the T84 side chain. Through such fine-tuning, target selection and downstream effects of a lectin can be modulated so as to knock down one activity while preserving another, thus providing tools for therapeutics and for understanding the Sugar Code. PMID:26496612

  3. Lectin-Like Bacteriocins from Pseudomonas spp. Utilise D-Rhamnose Containing Lipopolysaccharide as a Cellular Receptor

    PubMed Central

    Josts, Inokentijs; Roszak, Aleksander W.; Waløen, Kai I.; Cogdell, Richard J.; Milner, Joel; Evans, Tom; Kelly, Sharon; Tucker, Nicholas P.; Byron, Olwyn; Smith, Brian; Walker, Daniel

    2014-01-01

    Lectin-like bacteriocins consist of tandem monocot mannose-binding domains and display a genus-specific killing activity. Here we show that pyocin L1, a novel member of this family from Pseudomonas aeruginosa, targets susceptible strains of this species through recognition of the common polysaccharide antigen (CPA) of P. aeruginosa lipopolysaccharide that is predominantly a homopolymer of d-rhamnose. Structural and biophysical analyses show that recognition of CPA occurs through the C-terminal carbohydrate-binding domain of pyocin L1 and that this interaction is a prerequisite for bactericidal activity. Further to this, we show that the previously described lectin-like bacteriocin putidacin L1 shows a similar carbohydrate-binding specificity, indicating that oligosaccharides containing d-rhamnose and not d-mannose, as was previously thought, are the physiologically relevant ligands for this group of bacteriocins. The widespread inclusion of d-rhamnose in the lipopolysaccharide of members of the genus Pseudomonas explains the unusual genus-specific activity of the lectin-like bacteriocins. PMID:24516380

  4. The role of lectins and glycans in platelet clearance

    PubMed Central

    Hoffmeister, Karin M.

    2015-01-01

    Summary In recent years, it has become increasingly apparent that the life span of transfused platelets in circulation is regulated, at least in part, by glycan-lectin mediated mechanisms. There is clear evidence that refrigerated platelets are cleared by glycan-lectin mediated clearance mechanisms. Acute platelet cooling clusters glycoprotein (GP) Ibα receptors bearing uncovered N-acetylglucosamine (GlcNAc), and αMβ2 integrins on hepatic macrophages recognise clustered GlcNAc to rapidly clear these platelets from circulation. With prolonged refrigeration GPIbα clustering bearing uncovered galactose increases, which mediates the removal of long-term refrigerated platelets via hepatic Ashwell-Morell receptors (AMR), originally named as asialoglycoprotein receptors. In contrast, little is known about the molecular mechanisms of transfused room temperature platelet clearance. This review examines the role of glycan-lectin mediated clearance of exogenous, i.e. transfused chilled platelet clearance and briefly addresses the current knowledge of stored platelet function, degradation and its relation to platelet clearance. PMID:21781240

  5. Interfacing nanostructures to biological cells

    DOEpatents

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

    2012-09-04

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

  6. Lectins and substitution for helper function in anti-hapten responses in Xenopus laevis.

    PubMed

    Clothier, R H; James, H S; Ruben, L N; Balls, M

    1984-08-01

    Substitution by lectins for the carrier-priming requirement in thymus-dependent, antigen-binding responses in Xenopus laevis has been examined. Concanavalin A (Con A) was found to substitute for carrier priming in control, early-thymectomized and adult-thymectomized animals, but not in animals given a single, high dose of N-methyl-N-nitrosourea, which has a permanent effect on certain thymus-dependent functions in this species. Lipopolysaccharide and other lectins, such as peanut agglutinin and wheat germ agglutinin, were unable to substitute for carrier priming. These effects of Con A are discussed in terms of substitution via amplifier T cells or a helper T cell subset.

  7. Cytology of cardiac myxomas: presence of Ulex europaeus agglutinin-I (UEA-I) lectin by immunoperoxidase staining.

    PubMed

    Iwa, N; Yutani, C

    1993-12-01

    Cytological findings are presented of seven cases of cardiac myxomas. Avidin-biotin-peroxidase complex (ABC) method was employed to demonstrate Ulex europaeus agglutinin-I (UEA-I) lectin in imprint smears as well as in paraffin-embedded tissue sections in cardiac myxomas. The cytology was characterized by tumor cells with polyhedral or stellate and mucinous background with lymphocytes, neutrophils, and hemosiderin-laden macrophages. In smears as well as tissue sections, UEA-I lectin was detected throughout the cytoplasm of myxoma cells. This study established the applicability of the immunoperoxidase staining for cardiac myxoma as an aid in cytopathological diagnosis.

  8. 21 CFR 864.9550 - Lectins and protectins.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Lectins and protectins. 864.9550 Section 864.9550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Products Used In Establishments That Manufacture Blood...

  9. 21 CFR 864.9550 - Lectins and protectins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Lectins and protectins. 864.9550 Section 864.9550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Products Used In Establishments That Manufacture Blood...

  10. 21 CFR 864.9550 - Lectins and protectins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Lectins and protectins. 864.9550 Section 864.9550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Products Used In Establishments That Manufacture Blood...

  11. Mistletoe lectin is not the only cytotoxic component in fermented preparations of Viscum album from white fir (Abies pectinata)

    PubMed Central

    Eggenschwiler, Jenny; von Balthazar, Leopold; Stritt, Bianca; Pruntsch, Doreen; Ramos, Mac; Urech, Konrad; Rist, Lukas; Simões-Wüst, A Paula; Viviani, Angelika

    2007-01-01

    Background Preparations of mistletoe (Viscum album) are the form of cancer treatment that is most frequently used in the complementary medicine. Previous work has shown that these preparations are able to exert cytotoxic effects on carcinoma cells, the extent of which might be influenced by the host tree species and by the content of mistletoe lectin. Methods Using colorimetric assays, we have now compared the cytotoxic effects of Viscum album preparations (VAPs) obtained from mistletoe growing on oak (Quercus robur and Q. petraea, VAP-Qu), apple tree (Malus domestica,, VAP-M), pine (Pinus sylvestris, VAP-P) or white fir (Abies pectinata, VAP-A), on the in vitro growth of breast and bladder carcinoma cell lines. While MFM-223, KPL-1, MCF-7 and HCC-1937 were the breast carcinoma cell lines chosen, the panel of tested bladder carcinoma cells comprised the T-24, TCC-SUP, UM-UC-3 and J-82 cell lines. Results Each of the VAPs inhibited cell growth, but the extent of this inhibition differed with the preparation and with the cell line. The concentrations of VAP-Qu, VAP-M and VAP-A which led to a 50 % reduction of cell growth (IC50) varied between 0.6 and 0.03 mg/ml. Higher concentrations of VAP-P were required to obtain a comparable effect. Purified mistletoe lectin I (MLI) led to an inhibition of breast carcinoma cell growth at concentrations lower than those of VAPs, but the sensitivity towards purified MLI did not parallel that towards VAPs. Bladder carcinoma cells were in most cases more sensitive to VAPs treatment than breast carcinoma cells. The total mistletoe lectin content was very high in VAP-Qu (54 ng/mg extract), intermediate in VAP-M (25 ng/mg extract), and very low in VAP-P (1.3 ng/mg extract) and in VAP-A (1 ng/mg extract). As to be expected from the low content of mistletoe lectin, VAP-P led to relatively weak cytotoxic effects. Most remarkably, however, the lectin-poor VAP-A revealed a cytotoxic effect comparable to, or even stronger than, that of the lectin-rich VAP-Qu, on all tested bladder and breast carcinoma cell lines. Conclusion The results suggest the existence of cytotoxic components other than mistletoe lectin in VAP-A and reveal an unexpected potential of this preparation for the treatment of breast and bladder cancer. PMID:17493268

  12. Influence of the state of phase of lipid bilayer on the exposure of glucose residues on the surface of liposomes.

    PubMed

    Villalva, Denise Gradella; Giansanti, Luisa; Mauceri, Alessandro; Ceccacci, Francesca; Mancini, Giovanna

    2017-11-01

    The presence of carbohydrate-binding proteins (i.e. lectins) on the surface of various bacterial strains and their overexpression in some tumor tissues makes the use of glycosylated liposomes a promising approach for the specific drug delivery in antibacterial and anti-cancer therapies. However, the functionalization of liposome surface with sugar moieties by glycosylated amphiphiles does not ensure the binding of sugar-coated vesicles with lectins. In fact, the composition and properties of lipid bilayer play a pivotal role in the exposure of sugar residues and in the interaction with lectins. The influence of the length of the hydrophilic spacer that links the sugar to liposome surface and of the presence of saturated or unsaturated phospholipids in the lipid bilayer on the ability of glucosylated liposomes to interact with a model lectin, Concanavalin A, was investigated. Our results demonstrate that both the chain length and the prensece of unsaturation, parameters that strongly affect the fluidity of the lipid bilayer, affect agglutination. In particular, agglutination is favored when liposomes are in the gel phase within a defined range of temperature. Moreover, the obtained results confirm that the length of the PEG spacer, that influences both lipid organization and the exposure of sugar moieties to the bulk, plays a crucial role in liposome/lectin interaction. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Catfish (Clarias batrachus) serum lectin recognizes polyvalent Tn [alpha-D-GalpNAc1-Ser/Thr], Talpha [beta-D-Galp-(1-->3)-alpha-D-GalpNAc1-Ser/Thr], and II [beta-D-Galp(1-->4)-beta-D-GlcpNAc1-] mammalian glycotopes.

    PubMed

    Singha, Biswajit; Adhya, Mausumi; Chatterjee, Bishnu P

    2008-09-22

    A new calcium dependent GalNAc/Gal specific lectin was isolated from the serum of Indian catfish, Clarias batrachus and designated as C. batrachus lectin (CBL). It is a disulfide-linked homodecameric lectin of 74.65kDa subunits and the oligomeric form is essential for its activity. Binding specificity of CBL was investigated by enzyme-linked lectin-sorbent assay using a series of simple sugars, polysaccharides, and glycoproteins. GalNAc was more potent inhibitor than Gal; and alpha glycosides of both were more inhibitory than their beta counterparts. CBL showed maximum affinity for human tumor-associated Tn-antigens (GalNAcalpha1-Ser/Thr) at the molecular level and was 3.5 times higher than GalNAc. CBL interacted strongly with polyvalent Tn and Talpha (Galbeta1,3GalNAcalpha1-) as well as multivalent-II (Galbeta1,4GlcNAcbeta1-) antigens containing glycoproteins and intensity of inhibition was 10(3)-10(5) times more than monovalent ones. The overall specificity of CBL lies in the order of polyvalent Tn, Talpha and II>monovalent Tn > or = Me-alphaGalNAc>monovalent Talpha> Me-betaGalNAc>Me-alphaGal>monovalent T>GalNAc>monovalent F>monovalent II>Me-betaGal>Gal.

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

    DOE PAGES

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

    2015-09-21

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

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

    PubMed

    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.

  16. Docking, synthesis, and NMR studies of mannosyl trisaccharide ligands for DC-SIGN lectin.

    PubMed

    Reina, José J; Díaz, Irene; Nieto, Pedro M; Campillo, Nuria E; Páez, Juan A; Tabarani, Georges; Fieschi, Franck; Rojo, Javier

    2008-08-07

    DC-SIGN, a lectin, which presents at the surface of immature dendritic cells, constitutes nowadays a promising target for the design of new antiviral drugs. This lectin recognizes highly glycosylated proteins present at the surface of several pathogens such as HIV, Ebola virus, Candida albicans, Mycobacterium tuberculosis, etc. Understanding the binding mode of this lectin is a topic of tremendous interest and will permit a rational design of new and more selective ligands. Here, we present computational and experimental tools to study the interaction of di- and trisaccharides with DC-SIGN. Docking analysis of complexes involving mannosyl di- and trisaccharides and the carbohydrate recognition domain (CRD) of DC-SIGN have been performed. Trisaccharides Manalpha1,2[Manalpha1,6]Man 1 and Manalpha1,3[Manalpha1,6]Man 2 were synthesized from an orthogonally protected mannose as a common intermediate. Using these ligands and the soluble extracellular domain (ECD) of DC-SIGN, NMR experiments based on STD and transfer-NOE were performed providing additional information. Conformational analysis of the mannosyl ligands in the free and bound states was done. These studies have demonstrated that terminal mannoses at positions 2 or 3 in the trisaccharides are the most important moiety and present the strongest contact with the binding site of the lectin. Multiple binding modes could be proposed and therefore should be considered in the design of new ligands.

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

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

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

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

  18. Plant Defense Inhibitors Affect the Structures of Midgut Cells in Drosophila melanogaster and Callosobruchus maculatus

    PubMed Central

    Li-Byarlay, Hongmei; Pittendrigh, Barry R.; Murdock, Larry L.

    2016-01-01

    Plants produce proteins such as protease inhibitors and lectins as defenses against herbivorous insects and pathogens. However, no systematic studies have explored the structural responses in the midguts of insects when challenged with plant defensive proteins and lectins across different species. In this study, we fed two kinds of protease inhibitors and lectins to the fruit fly Drosophila melanogaster and alpha-amylase inhibitors and lectins to the cowpea bruchid Callosobruchus maculatus. We assessed the changes in midgut cell structures by comparing them with such structures in insects receiving normal diets or subjected to food deprivation. Using light and transmission electron microscopy in both species, we observed structural changes in the midgut peritrophic matrix as well as shortened microvilli on the surfaces of midgut epithelial cells in D. melanogaster. Dietary inhibitors and lectins caused similar lesions in the epithelial cells but not much change in the peritrophic matrix in both species. We also noted structural damages in the Drosophila midgut after six hours of starvation and changes were still present after 12 hours. Our study provided the first evidence of key structural changes of midguts using a comparative approach between a dipteran and a coleopteran. Our particular observation and discussion on plant–insect interaction and dietary stress are relevant for future mode of action studies of plant defensive protein in insect physiology. PMID:27594789

  19. Plant Defense Inhibitors Affect the Structures of Midgut Cells in Drosophila melanogaster and Callosobruchus maculatus.

    PubMed

    Li-Byarlay, Hongmei; Pittendrigh, Barry R; Murdock, Larry L

    2016-01-01

    Plants produce proteins such as protease inhibitors and lectins as defenses against herbivorous insects and pathogens. However, no systematic studies have explored the structural responses in the midguts of insects when challenged with plant defensive proteins and lectins across different species. In this study, we fed two kinds of protease inhibitors and lectins to the fruit fly Drosophila melanogaster and alpha-amylase inhibitors and lectins to the cowpea bruchid Callosobruchus maculatus. We assessed the changes in midgut cell structures by comparing them with such structures in insects receiving normal diets or subjected to food deprivation. Using light and transmission electron microscopy in both species, we observed structural changes in the midgut peritrophic matrix as well as shortened microvilli on the surfaces of midgut epithelial cells in D. melanogaster. Dietary inhibitors and lectins caused similar lesions in the epithelial cells but not much change in the peritrophic matrix in both species. We also noted structural damages in the Drosophila midgut after six hours of starvation and changes were still present after 12 hours. Our study provided the first evidence of key structural changes of midguts using a comparative approach between a dipteran and a coleopteran. Our particular observation and discussion on plant-insect interaction and dietary stress are relevant for future mode of action studies of plant defensive protein in insect physiology.

  20. Lectins as probes for assessing the accessibility of N-linked glycans in relation to the conformational changes of fibronectin.

    PubMed

    Agniel, Rémy; Vendrely, Charlotte; Poulouin, Laurent; Bascetin, Rümeyza; Benachour, Hamanou; Gallet, Olivier; Leroy-Dudal, Johanne

    2015-12-01

    Fibronectin, a ≈ 450-kDa protein with 4-9% (w/w) glycosylation, is a key component of extracellular matrices and has a high conformational lability regarding its functions. However, the accessibility and the role of glycosylated moieties associated with the conformational changes of fibronectin are poorly understood. Using lectins as probes, we developed an approach comprising dynamic light scattering, turbidimetry measurements, and isothermal titration calorimetry to assess the accessibility of glycosylated moieties of fibronectin undergoing thermal-induced conformational changes. Among a set of 14 lectins, fibronectin mainly reacted with mannose-binding lectins, specifically concanavalin A. When temperature was raised from 25 to 50 °C, fibronectin underwent progressive unfolding, but the conformation of concanavalin A was unaffected. Dynamic light scattering, turbidimetry measurements, and isothermal titration calorimetry showed increased concanavalin A binding to fibronectin during progressive thermal-induced unfolding of the protein core. Such data suggest that mannosylated residues are progressively exposed as fibronectin unfolds. Because oligosaccharide moieties can be differently exposed to cells, and the cell's responses could be modified physiologically or pathologically, modulation of fibronectin sugar chains could be relevant to its biological functions. Thus, lectins might be useful tools to probe the glycosylation accessibility accompanying changes in protein core folding, for which a better understanding would be of value for biological and biomedical research. Copyright © 2015 John Wiley & Sons, Ltd.

  1. Thrombomodulin-mediated cell adhesion: involvement of its lectin-like domain.

    PubMed

    Huang, Huey-Chun; Shi, Guey-Yueh; Jiang, Shinn-Jong; Shi, Chung-Sheng; Wu, Chun-Mei; Yang, Hsi-Yuan; Wu, Hua-Lin

    2003-11-21

    Thrombomodulin (TM) is an integral membrane glycoprotein that is a potent anticoagulant factor. TM may also possess functions distinct from its anticoagulant activity. Here the influence of TM on cell adhesion was studied in TM-negative melanoma A2058 cells transfected with green fluorescent protein-tagged TM (TMG) or lectin domain-deleted TM (TMG(DeltaL)). Confocal microscopy demonstrated that both TMG and TMG(DeltaL) were distributed in the plasma membrane. TMG-expressed cells grew as closely clustered colonies, with TM localized prominently in the intercellular boundaries. TMG(DeltaL)-expressed cells grew singly. Overexpression of TMG, but not TMG(DeltaL), decreased monolayer permeability in vitro and tumor growth in vivo. The cell-to-cell adhesion in TMG-expressed cells was Ca2+-dependent and was inhibited by monoclonal antibody against the lectin-like domain of TM. The effects of TM-mediated cell adhesion were abolished by the addition of mannose, chondroitin sulfate A, or chondroitin sulfate C. In addition, anti-lectin-like domain antibody disrupted the close clustering of the endogenous TM-expressed keratinocyte HaCaT cell line derived from normal human epidermis. Double-labeling immunofluorescence staining revealed similar distributions of TM and actin filament in the cortex region of the TMG-expressed cells. Thus, TM can function as a Ca2+-dependent cell-to-cell adhesion molecule. Binding of specific carbohydrates to the lectin-like domain is essential for this specific function.

  2. Multi-effect of the water-soluble Moringa oleifera lectin against Serratia marcescens and Bacillus sp.: antibacterial, antibiofilm and anti-adhesive properties.

    PubMed

    Moura, M C; Trentin, D S; Napoleão, T H; Primon-Barros, M; Xavier, A S; Carneiro, N P; Paiva, P M G; Macedo, A J; Coelho, L C B B

    2017-10-01

    To evaluate the antibiofilm potential of water-soluble Moringa oleifera seed lectin (WSMoL) on Serratia marcescens and Bacillus sp. WSMoL inhibited biofilm formation by S. marcescens at concentrations lower than 2·6 μg ml -1 and impaired bacterial growth at higher concentrations, avoiding biofilm formation. For Bacillus sp., the lectin inhibited bacterial growth at all concentrations. The antibiofilm action of WSMoL is associated with damage to bacterial cells. WSMoL did not disrupt preformed S. marcescens biofilms but was able to damage cells inside them. On the other hand, the lectin reduced the number of cells in Bacillus sp. biofilm treated with it. WSMoL was able to control biofilm formation when immobilized on glass surface (116 μg cm -2 ), damaging S. marcescens cells and avoiding adherence of Bacillus sp. cells on glass. The Bacillus sp. isolate is member of Bacillus subtilis species complex and closely related to species of the conspecific 'amyloliquefaciens' group. WSMoL prevented biofilm development by S. marcescens and Bacillus sp. and the antibiofilm effect is also observed when the lectin is immobilized on glass. Taking together, our results provide support to the potential use of WSMoL for controlling biofilm formation by bacteria. © 2017 The Society for Applied Microbiology.

  3. Glycophenotype Evaluation in Cutaneous Tumors Using Lectins Labeled with Acridinium Ester

    PubMed Central

    Lima, Luiza Rayanna Amorim; Almeida, Sinara Mônica Vitalino; Silva, Lúcia Patrícia Bezerra Gomes; Beltrão, Eduardo Isidoro Carneiro; Carvalho Júnior, Luiz Bezerra

    2013-01-01

    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(2,3)Gal 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. PMID:24167360

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

    PubMed

    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.

  5. Maize Root Lectins Mediate the Interaction with Herbaspirillum seropedicae via N-Acetyl Glucosamine Residues of Lipopolysaccharides

    PubMed Central

    Balsanelli, Eduardo; Tuleski, Thalita Regina; de Baura, Valter Antonio; Yates, Marshall Geoffrey; Chubatsu, Leda Satie; de Oliveira Pedrosa, Fabio; 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. PMID:24130823

  6. A tuber lectin from Arisaema helleborifolium Schott with anti-insect activity against melon fruit fly, Bactrocera cucurbitae (Coquillett) and anti-cancer effect on human cancer cell lines.

    PubMed

    Kaur, Manpreet; Singh, Kuljinder; Rup, Pushpinder J; Saxena, A K; Khan, Rizwan H; Ashraf, Mohd Tashfeen; Kamboj, Sukhdev Singh; Singh, Jatinder

    2006-01-01

    An anti-insect and anti-cancer lectin has been isolated from Arisaema helleborifolium Schott by affinity chromatography using asialofetuin-linked amino activated silica beads. The bound A. helleborifolium lectin (AHL) was eluted with 100mM glycine-HCl buffer, pH 2.5. It gave a single band on SDS-PAGE, pH 8.3, and PAGE, pH 4.5. However, multiple bands were obtained in PAGE at pH 8.3 and isoelectric focusing. The lectin was a homotetramer having subunit molecular mass 13.4kDa while its native molecular mass was 52kDa. It was a glycoprotein with 3.40% carbohydrate and was stable up to 60 degrees C for 30min. It showed anti-insect activity towards second instar larvae of Bactrocera cucurbitae (Coquillett) with LC(50) value of 16.4microg/ml. Larvae fed on artificial diet containing sub-lethal dose of AHL showed a significant decrease in acid phosphatase and alkaline phosphatase activity while esterase activity markedly increased as compared to larvae fed on diet without lectin. AHL was also found to inhibit in vitro proliferation of some well established human cancer cell lines viz HOP-62 (95%), HCT-15 (92%), HEP-2 (66%), HT-29 (68%), PC-3 (39.4%), and A-549 (20.7%).

  7. Transmission-blocking antibodies against mosquito C-type lectins for dengue prevention.

    PubMed

    Liu, Yang; Zhang, Fuchun; Liu, Jianying; Xiao, Xiaoping; Zhang, Siyin; Qin, Chengfeng; Xiang, Ye; Wang, Penghua; Cheng, Gong

    2014-02-01

    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.

  8. Microfibrillar associated protein 4 mfap4 genes in catfish play a novel role in innate immune responses

    USDA-ARS?s Scientific Manuscript database

    The lectin pathway of the complement system is characterized by two groups of soluble pattern recognition molecules, mannose-binding lectins (MBLs) and ficolins. These molecules recognize and bind carbohydrates in pathogens and activate complement leading to opsonization, leukocyte activation, and d...

  9. C-type lectins in immunity: recent developments

    PubMed Central

    Dambuza, Ivy M; Brown, Gordon D

    2015-01-01

    C-type lectin receptors (CLRs) comprise a large superfamily of proteins, which recognise a diverse range of ligands, and are defined by the presence of at least one C-type lectin-like domain (CTLD). Of particular interest are the single extracellular CTLD-containing receptors of the ‘Dectin-1’ and ‘Dectin-2’ clusters, which associate with signalling adaptors or possess integral intracellular signalling domains. These CLRs have traditionally been associated with the recognition of fungi, but recent discoveries have revealed diverse and unexpected functions. In this review, we describe their newly identified roles in anti-microbial host defence, homeostasis, autoimmunity, allergy and their functions in the recognition and response to dead and cancerous cells. PMID:25553393

  10. Functional Aspects of Fish Mucosal Lectins-Interaction with Non-Self.

    PubMed

    Brinchmann, Monica Fengsrud; Patel, Deepti Manjari; Pinto, Nevil; Iversen, Martin Haugmo

    2018-05-09

    Mucosal surfaces are of key importance in protecting animals against external threats including pathogens. In the mucosal surfaces, host molecules interact with non-self to prevent infection and disease. Interestingly, both inhibition and stimulation of uptake hinder infection. In this review, the current knowledgebase on teleost mucosal lectins’ ability to interact with non-self is summarised with a focus on agglutination, growth inhibition, opsonisation, cell adhesion, and direct killing activities. Further research on lectins is essential, both to understand the immune system of fishes, since they rely more on the innate immune system than mammals, and also to explore these molecules’ antibiotic and antiparasitic activities against veterinary and human pathogens.

  11. Cell Surface Changes Associated with Cellular Immune Reactions in Drosophila

    NASA Astrophysics Data System (ADS)

    Nappi, Anthony J.; Silvers, Michael

    1984-09-01

    In Drosophila melanogaster a temperature-induced change in immune competence accompanies cell surface alterations that cause its blood cells to adhere and to encapsulate a parasite. At 29 degrees C the blood cells of the tumorous-lethal (Tuml) mutant show a high degree of immune competence and encapsulate the eggs of the parasitic wasp Leptopilina heterotoma. At 21 degrees C the blood cells are essentially immune incompetent. High percentages of lectin binding cells were found under conditions which potentiated cellular encapsulation responses. Some immune reactive blood cells did not bind lectin. The low percentages of lectin binding cells in susceptible hosts suggest that developing parasites alter the cell surface of the blood cells of immune reactive hosts.

  12. Innate immune response of channel catfish (Ictalurus punctatus) mannose-binding lectin to channel catfish virus

    USDA-ARS?s Scientific Manuscript database

    The channel catfish virus (CCV) is a pathogenic herpesvirus that infects channel catfish (Ictalurus punctatus) in pond aquaculture in the Southeast USA. The innate immune protein mannose-binding lectin (MBL) could play an important role in the innate response of channel catfish by binding to the CC...

  13. Transcriptional Signatures in Response to Wheat Germ Agglutinin and Starvation in Drosophila melanogaster Larval Midgut

    USDA-ARS?s Scientific Manuscript database

    One function of plant lectins such as wheat germ agglutinin (WGA) is to serve as defenses against herbivorous insects. The midgut is one critical site affected by dietary lectins. We observed marked cellular, structural, and gene expression changes in the midguts of Drosophila melanogaster third-i...

  14. Alternate gram staining technique using a fluorescent lectin.

    PubMed Central

    Sizemore, R K; Caldwell, J J; Kendrick, A S

    1990-01-01

    Fluorescence-labeled wheat germ agglutinin binds specifically to N-acetylglucosamine in the outer peptidoglycan layer of gram-positive bacteria. The peptidoglycan layer of gram-negative bacteria is covered by a membrane and is not labeled by the lectin. By exploiting this phenomenon, an alternative Gram staining technique has been developed. Images PMID:1697149

  15. Regional differences in lectin binding patterns of vestibular hair cells

    NASA Technical Reports Server (NTRS)

    Baird, R. A.; Schuff, N. R.; Bancroft, J.

    1993-01-01

    Surface glycoconjugates of hair cells and supporting cells in the vestibular endorgans of the bullfrog were identified using biotinylated lectins with different carbohydrate specificities. Lectin binding in hair cells was consistent with the presence of glucose and mannose (CON A), galactose (RCA-I), N-acetylglucosamine (WGA), N-acetylgalactosamine (VVA), but not fucose (UEA-I) residues. Hair cells in the bullfrog sacculus, unlike those in the utriculus and semicircular canals, did not strain for N-acetylglucosamine (WGA) or N-acetylgalactosamine (VVA). By contrast, WGA and, to a lesser extent, VVA, differentially stained utricular and semicircular canal hair cells, labeling hair cells located in peripheral, but not central, regions. In mammals, WGA uniformly labeled Type I hair cells while labeling, as in the bullfrog, Type II hair cells only in peripheral regions. These regional variations were retained after enzymatic digestion. We conclude that vestibular hair cells differ in their surface glycoconjugates and that differences in lectin binding patterns can be used to identify hair cell types and to infer the epithelial origin of isolated vestibular hair cells.

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

    PubMed

    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.

  17. Glycosylation patterns of kidney proteins differ in rat diabetic nephropathy.

    PubMed

    Ravidà, Alessandra; Musante, Luca; Kreivi, Marjut; Miinalainen, Ilkka; Byrne, Barry; Saraswat, Mayank; Henry, Michael; Meleady, Paula; Clynes, Martin; Holthofer, Harry

    2015-05-01

    Diabetic nephropathy often progresses to end-stage kidney disease and, ultimately, to renal replacement therapy. Hyperglycemia per se is expected to have a direct impact on the biosynthesis of N- and O-linked glycoproteins. This study aims to establish the link between protein glycosylation and progression of experimental diabetic kidney disease using orthogonal methods. Kidneys of streptozotocin-diabetic and control rats were harvested at three different time points post streptozotocin injection. A panel of 12 plant lectins was used in the screening of lectin blots. The lectins UEAI, PHA-E, GSI, PNA, and RCA identified remarkable disease-associated differences in glycoprotein expression. Lectin affinity chromatography followed by mass spectrometric analyses led to the identification of several glycoproteins involved in salt-handling, angiogenesis, and extracellular matrix degradation. Our data confirm a substantial link between glycosylation signature and diabetes progression. Furthermore, as suggested by our findings on dipeptidyl peptidase-IV, altered protein glycosylation may reflect changes in biochemical properties such as enzymatic activity. Thus, our study demonstrates the unexplored potential of protein glycosylation analysis in the discovery of molecules linked to diabetic kidney disease.

  18. Comparison of antigen-capture ELISA to stool-culture methods for the detection of asymptomatic Entamoeba species infection in Kafer Daoud, Egypt.

    PubMed

    Abd-Alla, M D; Wahib, A A; Ravdin, J I

    2000-05-01

    We performed a prospective field study in the village of Kafer Daoud in Menofia, Egypt to compare the fecal culture method with enzyme linked immuno assay (ELISA) for detection of 170 kDa lectin antigen in feces for diagnosis of asymptomatic Entamoeba histolytica and Entamoeba dispar infection. All subjects with E. histolytica or E. dispar infection detected by culture also had positive ELISA for amebic antigen in their feces and an additional 57 Entameoba infections missed by culture were detected by ELISA (P < 0.001 compared to culture). The presence of fecal anti-lectin IgA antibodies and serum anti-LC3 (recombinant cysteine-rich lectin protein) IgG antibodies were positive predictors for E. histolytica infection (P < 0.03). Of interest, infection with Trichomonas hominis but not Blastocystis hominis was positively associated with E. histolytica infection (P < 0.05). In conclusion, ELISA for detection of fecal lectin antigen is a more sensitive method than fecal culture for detecting asymptomatic E. histolytica infection.

  19. Invertase proteinaceous inhibitor of Cyphomandra betacea Sendt fruits.

    PubMed

    Ordóñez, R M; Isla, M I; Vattuone, M A; Sampietro, A R

    2000-01-01

    This work describes a new invertase proteinaceous inhibitor from Cyphomandra betacea Sendt. (tomate de arbol) fruits. The proteinaceous inhibitor was isolated and purified from a cell wall preparation. The pH stability, kinetics of the inhibition of the C. betacea invertase, inhibition of several higher plant invertases and lectin nature of the inhibitor were studied. The inhibitor structure involves a single polypeptide (Mr = 19000), as shown by gel filtration and SDS-PAGE determinations. N-terminal aminoacid sequence was determined. The properties and some structural features of the inhibitor are compared with the proteinaceous inhibitors from several plant species (Beta vulgaris L., Ipomoea batatas L. and Lycopersicon esculentum Mill.). All these inhibitors share lectinic properties, some common epitopes, some aminoacid sequences and a certain lack of specificity towards invertases of different species, genera and even plant family. In consequence, the inhibitors appear to belong to the same lectin family. It is now known that some lectins are part of the defence mechanism of higher plants against fungi and bacteria and this is a probable role of the proteinaceous inhibitors.

  20. Expression of Ulex europaeus agglutinin I lectin-binding sites in squamous cell carcinomas and their absence in basal cell carcinomas. Indicator of tumor type and differentiation.

    PubMed

    Heng, M C; Fallon-Friedlander, S; Bennett, R

    1992-06-01

    Lectins bind tightly to carbohydrate moieties on cell surfaces. Alterations in lectin binding have been reported to accompany epidermal cell differentiation, marking alterations in membrane sugars during this process. The presence of UEA I (Ulex europaeus agglutinin I) L-fucose-specific lectin-binding sites has been used as a marker for terminally differentiated (committed) keratinocytes. In this article, we report the presence of UEA-I-binding sites on squamous keratinocytes of well-differentiated squamous cell carcinomas, with patchy loss of UEA I positivity on poorly differentiated cells of squamous cell carcinomas, suggesting a possible use for this technique in the rapid assessment of less differentiated areas within the squamous cell tumor. The absence of UEA-I-binding sites on basal cell carcinomas may be related to an inability of cells comprising this tumor to convert the L-D-pyranosyl moiety on basal cells to the L-fucose moiety, resulting in an inability of basal cell carcinoma cell to undergo terminal differentiation into a committed keratinocyte.

  1. Two mannose-binding lectin homologues and an MBL-associated serine protease are expressed in the gut epithelia of the urochordate species Ciona intestinalis.

    PubMed

    Skjoedt, Mikkel-Ole; Palarasah, Yaseelan; Rasmussen, Karina; Vitved, Lars; Salomonsen, Jan; Kliem, Anette; Hansen, Soren; Koch, Claus; Skjodt, Karsten

    2010-01-01

    The lectin complement pathway has important functions in vertebrate host defence and accumulating evidence of primordial complement components trace its emergence to invertebrate phyla. We introduce two putative mannose-binding lectin homologues (CioMBLs) from the urochordate species Ciona intestinalis. The CioMBLs display similarities with vertebrate MBLs and comprise a collagen-like region, alpha-helical coiled-coils and a carbohydrate recognition domain (CRD) with conserved residues involved in calcium and carbohydrate binding. Structural analysis revealed an oligomerization through interchain disulphide bridges between N-terminal cysteine residues and cysteines located between the neck region and the CRD. RT-PCR showed a tissue specific expression of CioMBL in the gut and by immunohistochemistry analysis we also demonstrated that CioMBL co-localize with an MBL-associated serine protease in the epithelia cells lining the stomach and intestine. In conclusion we present two urochordate MBLs and identify an associated serine protease, which support the concept of an evolutionary ancient origin of the lectin complement pathway.

  2. Real-time analysis of the carbohydrates on cell surfaces using a QCM biosensor: a lectin-based approach.

    PubMed

    Pei, Zhichao; Saint-Guirons, Julien; Käck, Camilla; Ingemarsson, Björn; Aastrup, Teodor

    2012-05-15

    A novel approach to the study of molecular interactions on the surface of mammalian cells using a QCM biosensor was developed. For this study, an epidermoid carcinoma cell line (A-431) and a breast adenocarcinoma cell line (MDA-MB-468) were immobilized onto polystyrene-coated quartz crystals. The binding and dissociation between the lectin Con A and the cells as well as the inhibition of the binding by monosaccharides were monitored in real time and provided an insight into the complex avidic recognition of cell glycoconjugates. The real-time lectin screening of a range of lectins, including Con A, DBA, PNA and UEA-I, enabled the accurate study of the glycosylation changes between cells, such as changes associated with cancer progression and development. Furthermore, the kinetic parameters of the interaction of Con A with MDA-MB-468 cells were studied. This application provides investigators in the field of glycobiology with a novel tool to study cell surface glycosylation and may also have impacts on drug discovery. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. A simple and accessible synthetic lectin for glucose recognition and sensing

    NASA Astrophysics Data System (ADS)

    Ke, Chenfeng; Destecroix, Harry; Crump, Matthew P.; Davis, Anthony P.

    2012-09-01

    Binding carbohydrates from water is a difficult task, even for the natural carbohydrate-binding proteins known as lectins. The design of synthetic lectin mimics is correspondingly challenging, especially if good selectivities are required. In previous work we showed that success is possible, but only for complex polycyclic architectures that require lengthy and low-yielding syntheses; for example, one glucose-selective system was made in 21 steps and only 0.1% overall yield. Here we report the discovery of a simple monocyclic host that matches the earlier designs, but is far more accessible as it is prepared in just five steps and 23% overall yield. The new synthetic lectin binds glucose with excellent selectivity versus other common monosaccharides (for example, ∼50:1 versus galactose) and sufficient affinity for glucose sensing at the concentrations found in blood. It also features a built-in signalling system in the form of strong and guest-dependent fluorescence emission. The effectiveness and simplicity of this molecule suggests the potential for development into a new methodology for practical glucose monitoring.

  4. Binding of isolated plant lectin by rhizobia during episodes of reduced gravity obtained by parabolic flight

    NASA Technical Reports Server (NTRS)

    Henry, R. L.; Green, P. D.; Wong, P. P.; Guikema, J. A.; Spooner, B. S. (Principal Investigator)

    1990-01-01

    Development of a legume root nodule is a complex process culminating in a plant/bacterial symbiosis possessing the capacity for biological dinitrogen fixation. Formation of root nodules is initiated by the binding and stabilization of rhizobia to plant root hairs, mediated in part by a receptor/ligand recognition system composed of lectins on the plant root surface and lectin-binding sites on the rhizobial cell surface. The dinitrogen fixation activity of these root nodules may be an important feature of enclosed, space-based life support systems, and may provide an ecological method to recycle nitrogen for amino acid production. However, the effects on nodule development of varied gravitational fields, or of root nutrient delivery hardware, remain unknown. We have investigated the effects of microgravity on root nodule formation, with preliminary experiments focused upon the receptor/ligand component. Microgravity, obtained during parabolic flight aboard NASA 930, has no apparent effect on the binding of purified lectin to rhizobia, a result that will facilitate forthcoming experiments using intact root tissues.

  5. Lectin activity of species of genus Cerrena S.F. Gray (Aphyllophoromycetideae) in submerged fermentation of lignocellulosic materials.

    PubMed

    Davitashvili, Elene; Kapanadze, Ekaterine; Kachlishvili, Eva; Elisashvili, Vladimir

    2011-01-01

    The capability of 5 strains of 2 species of genus Cerrena (Aphyllophoromycetideae) to express hemagglutinating activity (HA) was evaluated in submerged fermentation of 7 lignocellulosic materials of different chemical compositions. Among the lignocellulosic substrates tested, walnut pericarp, followed by mandarin and kiwi peels provided the highest specific HA of C. unicolor IBB 300; walnut leaves and pericarp appeared to be the best substrates for the accumulation of lectin by C. unicolor IBB 301, whereas the fermentation of kiwi peels ensured the highest HA of C. unicolor IBB 302. The highest HA was detected in C. maxima IBB 402 cultivation in submerged fermentation of walnut leaves (64103 U/mg), mandarin (33333 U/mg) and kiwi peels (28571 U/mg). Moreover, the fermentation of walnut pericarp and leaves provided the secretion of high lectin levels in culture liquid (9143 U/mg). The carbohydrate specificity of tested preparations significantly depended on both fungus strain and lignocellulosic growth substrate. By substitution of lignocellulosic material, it is possible to regulate lectin production and to obtain a preparation with different specificity toward carbohydrates.

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

    PubMed

    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.

  7. Step-By-Step In Vitro Mutagenesis: Lessons From Fucose-Binding Lectin PA-IIL.

    PubMed

    Mrázková, Jana; Malinovská, Lenka; Wimmerová, Michaela

    2017-01-01

    Site-directed mutagenesis is a powerful technique which is used to understand the basis of interactions between proteins and their binding partners, as well as to modify these interactions. Methods of rational design that are based on detailed knowledge of the structure of a protein of interest are often used for preliminary investigations of the possible outcomes which can result from the practical application of site-directed mutagenesis. Also, random mutagenesis can be used in tandem with site-directed mutagenesis for an examination of amino acid "hotspots."Lectins are sugar-binding proteins which, among other functions, mediate the recognition of host cells by a pathogen and its adhesion to the host cell surface. Hence, lectins and their binding properties are studied and engineered using site-directed mutagenesis.In this chapter, we describe a site-directed mutagenesis method used for investigating the sugar binding pattern of the PA-IIL lectin from the pathogenic bacterium Pseudomonas aeruginosa. Moreover, procedures for the production and purification of PA-IIL mutants are described, and several basic methods for characterizing the mutants are discussed.

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

    PubMed

    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.

  9. Fluorescence emission and polarization analyses for evaluating binding of ruthenium metalloglycocluster to lectin and tetanus toxin c-fragment

    NASA Astrophysics Data System (ADS)

    Okada, Tomoko; Minoura, Norihiko

    2010-02-01

    We have developed a fluorescent ruthenium metalloglycocluster as a powerful molecular probe for evaluating a binding event between carbohydrates and lectins by fluorescence emission (FE) and fluorescence polarization (FP) analysis. The fluorescent ruthenium metalloglycoclusters, [Ru(bpy-2Gal)3] and [Ru(bpy-2Glc)3], possess clustered galactose and glucose surrounding the ruthenium center. Changes in FE and FP of these metalloglycoclusters were measured by adding each lectin (Peanut agglutinin (PNA), Ricinus communis agglutinin 120 (RCA), Concanavalin A (ConA), or Wheat germ agglutinin (WGA)) or tetanus toxin c-fragment (TCF). Following the addition of PNA, the FE spectrum of [Ru(bpy- 2Gal)3] showed new emission peak and the FP value of [Ru(bpy-2Gal)3] increased. Similarly, the FE spectrum of [Ru(bpy-2Glc)3] showed new emission peak and the FP value increased following the addition of ConA. Since other combinations of the metalloglycoclusters and lectin caused little change, specific bindings of galactose to PNA and glucose to ConA were proved by the FE and FP measurement. From nonlinear least-squares fitting, dissociation constants (Kd) of [Ru(bpy-2Gal)3] to PNA was 6.1 μM, while the Kd values of [Ru(bpy)2(bpy-2Gal)] to PNA was ca. 10-4 M. Therefore, the clustered carbohydrates were proved to increase affinity to lectins. Furthermore, the FP measurements proved specific binding of [Ru(bpy-2Gal)3] to TCF.

  10. Identification of a new C-type lectin, TES-70, secreted by infective larvae of Toxocara canis, which binds to host ligands.

    PubMed

    Loukas, A; Doedens, A; Hintz, M; Maizels, R M

    2000-11-01

    Infective larvae of the dog roundworm Toxocara canis survive in the tissues of their hosts for extended periods in a state of developmental arrest, successfully evading immune destruction. This survival strategy is thought to be mediated by T. canis excretory/secretory (TES) products which downregulate or divert the immune response. We purified one of the major TES products, TES-70 and gained amino acid sequence from 4 tryptic peptides. These peptides were matched to a predicted protein from a cDNA that was isolated by expression screening a T. canis cDNA library with mouse anti-TES serum. The predicted protein (Tc-CTL-4) is similar to, but larger than, Tc-CTL-1, a 32-kDa C-type lectin secreted by T. canis larvae. Tc-CTL-4 has a signal peptide, 2 Cys-rich domains and a C-terminal calcium-dependent C-type lectin domain that shares sequence similarity with host immune cell receptors such as macrophage mannose receptor and CD23. The lectin domain was expressed in bacteria and antiserum to the purified recombinant protein was used to confirm that Tc-ctl-4 did encode the native TES-70 glycoprotein. TES-70 selectively bound to ligands on the surface of Madin-Darby Canine Kidney cells in vitro in a calcium-dependent manner, inhibitable by mammalian serum, indicating that a host glycan is the native ligand for this new parasite lectin.

  11. Glycans: bioactive signals decoded by lectins.

    PubMed

    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.

  12. Knowledge-based modeling of a legume lectin and docking of the carbohydrate ligand: the Ulex europaeus lectin I and its interaction with fucose.

    PubMed

    Gohier, A; Espinosa, J F; Jimenez-Barbero, J; Carrupt, P A; Pérez, S; Imberty, A

    1996-12-01

    Ulex europaeus isolectin I is specific for fucose-containing oligosaccharide such as H type 2 trisaccharide alpha-L-Fuc (1-->2) beta-D-Gal (1-->4) beta-D-GlcNAc. Several legume lectins have been crystallized and modeled, but no structural data are available concerning such fucose-binding lectin. The three-dimensional structure of Ulex europaeus isolectin I has been constructed using seven legume lectins for which high-resolution crystal structures were available. Some conserved water molecules, as well as the structural cations, were taken into account for building the model. In the predicted binding site, the most probable locations of the secondary hydroxyl groups were determined using the GRID method. Several possible orientations could be determined for a fucose residue. All of the four possible conformations compatible with energy calculations display several hydrogen bonds with Asp-87 and Ser-132 and a stacking interaction with Tyr-220 and Phe-136. In two orientations, the O-3 and O-4 hydroxyl groups of fucose are the most buried ones, whereas two other, the O-2 and O-3 hydroxyl groups are at the bottom of the site. Possible docking modes are also studied by analysis of the hydrophobic and hydrophilic surfaces for both the ligand and the protein. The SCORE method allows for a quantitative evaluation of the complementarity of these surfaces, on the basis of molecular lipophilicity calculations. The predictions presented here are compared with known biochemical data.

  13. Eutirucallin, a RIP-2 Type Lectin from the Latex of Euphorbia tirucalli L. Presents Proinflammatory Properties

    PubMed Central

    Santana, Sanzio Silva; Gennari-Cardoso, Margareth Leitão; Carvalho, Fernanda Caroline; Roque-Barreira, Maria Cristina; Santiago, André da Silva; Alvim, Fátima Cerqueira; Pirovani, Carlos Priminho

    2014-01-01

    Lectins are carbohydrate-binding proteins that recognize and modulate physiological activities and have been used as a toll for detection and identification of biomolecules, and therapy of diseases. In this study we have isolated a lectin present in the latex of Euphorbia tirucalli, and named it Eutirucallin. The latex protein extract was subjected to ion exchange chromatography and showed two peaks with haemagglutinating activity. Polypeptides of 32 kDa protein extract strongly interacted with immobilized galactose (α-lactose > D-N-acetylgalactosamine). The Eutirucallin was obtained with a yield of 5.6% using the α-lactose column. The lectin domain has 32 kDa subunits and at least two of which are joined by disulfide bridges. The agglutinating capacity for human erythrocytes A+, B+ and O+ is inhibited by D-galactose. The haemagglutinating activity of Eutirucallin was independent of Ca2+ and maintained until the temperature of 55°C. Eutirucallin presented biological activities such as neutrophils recruitment and cytokine prodution by macrophages. The analysis of the trypsin-digested Eutirucallin by ms/ms in ESI-Q-TOFF resulted in nine peptides similar to type 2 ribosome-inactivating protein (type-2 RIP). It's partial sequence showed a similarity of 67.4 – 83.1% for the lectin domain of type-2 RIP [Ricin and Abrin (83.1%), Viscumin, Ebulin, Pulchellin, Cinnamomin, Volkensin and type-2 RIP Iris hollandica]. Our data suggest that Eutirucallin is a new member of type 2 ribosome-inactivating protein and presents biotechnological potential. PMID:24558388

  14. nES GEMMA Analysis of Lectins and Their Interactions with Glycoproteins - Separation, Detection, and Sampling of Noncovalent Biospecific Complexes

    NASA Astrophysics Data System (ADS)

    Engel, Nicole Y.; Weiss, Victor U.; Marchetti-Deschmann, Martina; Allmaier, Günter

    2017-01-01

    In order to better understand biological events, lectin-glycoprotein interactions are of interest. The possibility to gather more information than the mere positive or negative response for interactions brought mass spectrometry into the center of many research fields. The presented work shows the potential of a nano-electrospray gas-phase electrophoretic mobility molecular analyzer (nES GEMMA) to detect weak, noncovalent, biospecific interactions besides still unbound glycoproteins and unreacted lectins without prior liquid phase separation. First results for Sambucus nigra agglutinin, concanavalin A, and wheat germ agglutinin and their retained noncovalent interactions with glycoproteins in the gas phase are presented. Electrophoretic mobility diameters (EMDs) were obtained by nES GEMMA for all interaction partners correlating very well with molecular masses determined by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) of the individual molecules. Moreover, EMDs measured for the lectin-glycoprotein complexes were in good accordance with theoretically calculated mass values. Special focus was laid on complex formation for different lectin concentrations and binding specificities to evaluate the method with respect to results obtained in the liquid phase. The latter was addressed by capillary electrophoresis on-a-chip (CE-on-a-chip). Of exceptional interest was the fact that the formed complexes could be sampled according to their size onto nitrocellulose membranes after gas-phase separation. Subsequent immunological investigation further proved that the collected complex actually retained its native structure throughout nES GEMMA analysis and sampling.

  15. Lectin histochemistry reveals SNA as a prognostic carbohydrate-dependent probe for invasive ductal carcinoma of the breast: a clinicopathological and immunohistochemical auxiliary tool

    PubMed Central

    dos-Santos, Petra B; Zanetti, Juliana S; Vieira-de-Mello, Gabriela S; Rêgo, Moacyr BM; A, Alfredo Ribeiro-Silva; Beltrão, Eduardo Isidoro Carneiro

    2014-01-01

    Increased sialylation and β1,6-branched oligosaccharides has been associated with a variety of structural changes in cell surface carbohydrates, most notably in tumorigenesis. Lectins are defined as proteins that preferentially recognize and bind carbohydrate complexes protruding from glycolipids and glycoproteins. This interaction with carbohydrates can be as specific as the interaction between antigen and antibody. Due to this type of interaction lectins have been used as experimental auxiliary tools in histopathological diagnosis of cancer. This study was designed to evaluate the differential expression of sialic acids and β1,6-N-acetylglucosaminyltransferase V (MGAT5) in invasive (IDC) and in situ (DCIS) ductal carcinoma of the breast and its possible application as prognostic biomarkers. A possible transition between pre-malign and malign lesions was evaluated using DCIS samples. Biopsies were analyzed regarding the expression of MUC1, p53, Ki-67, estrogen receptor, progesterone receptor, HER-2 and MGAT5. α2,6-linked sialic acids residues recognized by SNA lectin was overexpressed in 33.3% of IDC samples and it was related with Ki-67 (p=0.042), PR (p=0.029), lymphnodes status (p=0.017) and death (p=0.011). Regarding survival analysis SNA was the only lectin able to correlate with specific-disease survival and disease-free survival (p=0.024 and p=0.041, respectively), besides, it presents itself as an independent variable by Cox Regression analysis (p= 0.004). Comparing IDC and DCIS cases, only SNA showed different staining pattern (p=0.034). The presence of sialic acids on tumor cell surface can be an indicative of poor prognosis and our study provides further evidence that SNA lectin can be used as a prognostic probe in IDC and DCIS patients. PMID:24966944

  16. Identification and transcriptional analysis of two types of lectins (SgCTL-1 and SgGal-1) from mollusk Solen grandis.

    PubMed

    Wei, Xiumei; Yang, Jianmin; Liu, Xiangquan; Yang, Dinglong; Xu, Jie; Fang, Jinghui; Wang, Weijun; Yang, Jialong

    2012-08-01

    C-type lectin and galectin are two types of animal carbohydrate-binding proteins which serve as pathogen recognition molecules and play crucial roles in the innate immunity of invertebrates. In the present study, a C-type lectin (designated as SgCTL-1) and galectin (designated as SgGal-1) were identified from mollusk Solen grandis, and their expression patterns, both in tissues and toward three pathogen-associated molecular patterns (PAMPs) stimulation were characterized. The full-length cDNA of SgCTL-1 and SgGal-1 was 1280 and 1466 bp, containing an open reading frame (ORF) of 519 and 1218 bp, respectively. Their deduced amino acid sequences showed high similarity to other members of C-type lectin and galectin superfamily, respectively. SgCTL-1 encoded a single carbohydrate-recognition domain (CRD), and the motif of Ca(2+)-binding site 2 was EPN (Glu(135)-Pro(136)-Asn(137)). While SgGal-1 encoded two CRDs, and the amino acid residues constituted the carbohydrate-binding motifs were well conserved in CRD1 but partially conserved in CRD2. Although SgCTL-1 and SgGal-1 exhibited different tissue expression pattern, they were both constitutively expressed in all tested tissues, including hemocytes, gonad, mantle, muscle, gill and hepatopancreas, and they were both highly expressed in hepatopancreas and gill. Furthermore, the mRNA expression of two lectins in hemocytes was significantly (P < 0.01) up-regulated with different levels after S. grandis were stimulated by lipopolysaccharide (LPS), peptidoglycan (PGN) or β-1,3-glucan. Our results suggested that SgCTL-1 and SgGal-1 from razor clam were two novel members of animal lectins, and they might function as pattern recognition receptors (PRRs) taking part in the process of pathogen recognition. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Lectin histochemistry of metastatic adenocarcinomas of the lung.

    PubMed

    Thöm, Ina; Schult-Kronefeld, Olaf; Burkholder, Iris; Goern, Michael; Andritzky, Birte; Blonski, Katharina; Kugler, Christian; Edler, Lutz; Bokemeyer, Carsten; Schumacher, Udo; Laack, Eckart

    2007-06-01

    Several clinical studies indicate that primary tumour cells with high metastatic potential often show aberrant glycosylation as detected by lectin histochemistry. However, it is unclear whether aberrant glycosylation is still present in metastatic deposits. The aim of the present investigation was thus to analyse a possible association between the presence of lectin binding sites of pulmonary adenocarcinoma cells and their lymph node and haematogenous metastatic cells. For this purpose, the expression of HPA, PHA-L and UEA-I was assessed in primary tumours, lymph node metastases and haematogenous metastases of 96 patients with metastatic adenocarcinomas of the lung that underwent surgery between 1999 and 2002. Besides, lectin-binding data and other known prognostic factors were correlated with survival. We found a significant positive correlation between the binding of the lectins HPA (p=0.002), PHA-L (p<0.00001) and UEA-I (p<0.00001) to the cells of the primary tumour and to their lymph node metastases. There was a positive correlation between the binding of HPA to the cells of the primary tumour and the haematogenous metastases as well. Patients with tumours which did not show HPA binding sites had a median overall survival of 27.9 months (95%-CI 7.7-infinity months). Patients with a HPA binding tumour had a median overall survival of 20.9 months (95%-CI 18.5-28.7 months). This is the first investigation to demonstrate a positive correlation between the binding of the lectins HPA, PHA-L and UEA-I to the cells of the primary tumour and to their lymph node metastases. Expression of HPA binding sites is also preserved in the haematogenous metastases. In summary, our results support the hypothesis that altered glycosylation of the membrane-bound glycoproteins of the tumour cells is associated with, but not sufficient for promotion of lymphogenic and haematogenous metastasis.

  18. The 2.2 A resolution structure of the O(H) blood-group-specific lectin I from Ulex europaeus.

    PubMed

    Audette, G F; Vandonselaar, M; Delbaere, L T

    2000-12-01

    The tertiary and quaternary structure of the lectin I from Ulex europaeus (UE-I) has been determined to 2.2 A resolution. UE-I is a dimeric metalloglycoprotein that binds the H-type 2 human blood group determinant [alpha-L-Fucalpha(1-->2)-beta-D-Galbeta(1-->4)-beta-D-Glc NAcalpha-]. Nine changes from the published amino acid sequence were necessary to account for the electron density. The quaternary structural organization of UE-I is that of the most commonly occurring legume lectin dimer. The tertiary structure of the monomeric subunits is similar to that in the conventional lectin subunit; however, some structural differences are noted. These differences include a four-stranded anti-parallel "S" sheet in UE-I versus the five-stranded S sheet in other lectin monomers. The Ala residue of the Ala-Asp cis-peptide bond present in the carbohydrate-binding site of the conventional lectin monomer is replaced with a Thr in the UE-I structure. Also, a novel disulfide bridge linking Cys115 and Cys150 is present. There are two metallic ions, one calcium and the other manganese, per subunit. N-linked oligosaccharides are at residues 23 and 111 of each subunit. One molecule of R-2-methyl-2, 4-pentanediol (R-MPD) is present in a shallow depression on the surface of each subunit. In order to examine the binding of the H-type 2 blood group determinant by UE-I, its beta-methyl glycoside (H-type 2-OMe) was docked into the binding site of R-MPD. The epitope previously identified for H-type 2-OMe by chemical mapping proved, with only minor adjustment of amino acid residues, to be complementary to the shallow cavity occupied by R-MPD in the structure. Several key interactions have been proposed between the H-type 2-OMe and UE-I. Copyright 2000 Academic Press.

  19. Genomic Analysis of Storage Protein Deficiency in Genetically Related Lines of Common Bean (Phaseolus vulgaris)

    PubMed Central

    Pandurangan, Sudhakar; Diapari, Marwan; Yin, Fuqiang; Munholland, Seth; Perry, Gregory E.; Chapman, B. Patrick; Huang, Shangzhi; Sparvoli, Francesca; Bollini, Roberto; Crosby, William L.; Pauls, Karl P.; Marsolais, Frédéric

    2016-01-01

    A series of genetically related lines of common bean (Phaseolus vulgaris L.) integrate a progressive deficiency in major storage proteins, the 7S globulin phaseolin and lectins. SARC1 integrates a lectin-like protein, arcelin-1 from a wild common bean accession. SMARC1N-PN1 is deficient in major lectins, including erythroagglutinating phytohemagglutinin (PHA-E) but not α-amylase inhibitor, and incorporates also a deficiency in phaseolin. SMARC1-PN1 is intermediate and shares the phaseolin deficiency. Sanilac is the parental background. To understand the genomic basis for variations in protein profiles previously determined by proteomics, the genotypes were submitted to short-fragment genome sequencing using an Illumina HiSeq 2000/2500 platform. Reads were aligned to reference sequences and subjected to de novo assembly. The results of the analyses identified polymorphisms responsible for the lack of specific storage proteins, as well as those associated with large differences in storage protein expression. SMARC1N-PN1 lacks the lectin genes pha-E and lec4-B17, and has the pseudogene pdlec1 in place of the functional pha-L gene. While the α-phaseolin gene appears absent, an approximately 20-fold decrease in β-phaseolin accumulation is associated with a single nucleotide polymorphism converting a G-box to an ACGT motif in the proximal promoter. Among residual lectins compensating for storage protein deficiency, mannose lectin FRIL and α-amylase inhibitor 1 genes are uniquely present in SMARC1N-PN1. An approximately 50-fold increase in α-amylase inhibitor like protein accumulation is associated with multiple polymorphisms introducing up to eight potential positive cis-regulatory elements in the proximal promoter specific to SMARC1N-PN1. An approximately 7-fold increase in accumulation of 11S globulin legumin is not associated with variation in proximal promoter sequence, suggesting that the identity of individual proteins involved in proteome rebalancing might also be determined at the translational level. PMID:27066039

  20. 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.

    PubMed

    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).

  1. 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.

    PubMed

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

    2016-04-01

    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 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 a litter 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).

  2. Structural studies of the carbohydrate moieties of lectins from potato (Solanum tuberosum) tubers and thorn-apple (Datura stramonium) seeds

    PubMed Central

    Ashford, David; Desai, Nila N.; Allen, Anthony K.; Neuberger, Albert; O'Neill, Malcolm A.; Selvendran, Robert R.

    1982-01-01

    1. Methylation analysis of potato (Solanum tuberosum) lectin and thorn-apple (Datura stramonium) lectin confirmed previous conclusions that both glycoproteins contained high proportions of l-arabinofuranosides and lesser amounts of d-galactopyranosides. The arabinofuranosides are present in both lectins as short unbranched chains containing 1→2- and 1→3-linkages, which are known to be linked to hydroxyproline. Galactopyranosides are present as monosaccharides, which are known to be attached to serine, in potato lectin and as both the monosaccharide and the 1→3-linked disaccharide in Datura lectin. 2. Alkaline digestion of potato lectin and subsequent separation of the components by gel filtration led to the isolation of four fractions corresponding to the mono-, di-, tri- and tetra-arabinosides of hydroxyproline. The latter two fractions accounted for over 70% of the total hydroxyproline. 3. Methylation analysis was used to show that the triarabinoside contained only 1→2-linkages between sugars, but that the tetra-arabinoside contained both 1→2- and 1→3-linkages. Direct-insertion mass spectrometry of these compounds using electron impact and chemical ionization, in a comparison with other known structural patterns, was used to determine the sequences of the sugars, which were Araƒ1→2Araƒ1→2Araƒ1→Hyp and Araƒ1→3Araƒ1→2Araƒ1→2Araƒ 1→Hyp. 4. On the basis of optical rotation it had previously been suggested [Allen, Desai, Neuberger & Creeth (1978) Biochem. J. 171, 665–674] that all the arabinose of potato lectin was present as the β-l-furanoside. However, measurement of the optical rotations of the hydroxyprolyl arabinosides showed that whereas the diarabinoside had a molar rotation ([m]) value close to that predicted, the triarabinoside was more dextrorotatory and the tetra-arabinoside was less dextrorotatory than expected. Possible explanations for these findings are that, although the di- and tri-arabinosides contain exclusively β-arabinofuranosides, in the tri-arabinoside, interactions between pentose units lead to an enhanced positive rotation. The tetra-arabinoside, however, is proposed to contain a single α-arabinofuranoside residue, which is responsible for the lower than expected positive rotation. The observed rotation of the tetra-arabinoside was found to be close to the theoretical value predicted on that basis. Furthermore, the action of a specific α-arabinofuranosidase on the tetrasaccharide was to remove a single arabinose residue, presumably the terminal non-reducing sugar, and to produce a product that was indistinguishable on electrophoresis from the triarabinoside. Changes in rotation were compatible with this assumption. 5. It is concluded that the structures of the hydroxyprolyl tri- and tetra-arabinosides of potato lectin are: βAraƒ1→2βAraƒ1→2βAraƒ1→Hyp and αAraƒ1→3βAraƒ1→2βAraƒ 1→2βAraƒ1→Hyp. These are identical with compounds that have been isolated from the insoluble hydroxyproline-rich glycoproteins of plant cell walls. PMID:7082284

  3. Impact of oral and waterborne administration of rhamnolipids on the susceptibility of channel catfish (Ictalurus punctatus) to Flavobacterium columnare infection

    USDA-ARS?s Scientific Manuscript database

    Flavobacterium columnare is the causative agent of columnaris disease and causes tremendous morbidity and mortality of farmed fish globally. Previously, we identified a potential lectin-mediator (a rhamnose-binding lectin; RBL1a) of F. columnare adhesion and showed higher RBL1a expression in suscept...

  4. Characterization of Extracellular Proteins in Tomato Fruit using Lectin Affinity Chromatography and LC-MALDI-MS/MS analysis

    USDA-ARS?s Scientific Manuscript database

    The large-scale isolation and analysis of glycoproteins by lectin affinity chromatography coupled with mass spectrometry has become a powerful tool to monitor changes in the “glycoproteome” of mammalian cells. Thus far, however, this approach has not been used extensively for the analysis of plant g...

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

    PubMed

    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.

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

    PubMed

    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.

  7. Photoswitchable Janus glycodendrimer micelles as multivalent inhibitors of LecA and LecB from Pseudomonas aeruginosa.

    PubMed

    Hu, Yingxue; Beshr, Ghamdan; Garvey, Christopher J; Tabor, Rico F; Titz, Alexander; Wilkinson, Brendan L

    2017-11-01

    The first example of the self-assembly and lectin binding properties of photoswitchable glycodendrimer micelles is reported. Light-addressable micelles were assembled from a library of 12 amphiphilic Janus glycodendrimers composed of variable carbohydrate head groups and hydrophobic tail groups linked to an azobenzene core. Spontaneous association in water gave cylindrical micelles with uniform size distribution as determined by dynamic light scattering (DLS) and small angle neutron scattering (SANS). Trans-cis photoisomerization of the azobenzene dendrimer core was used to probe the self-assembly behaviour and lectin binding properties of cylindrical micelles, revealing moderate-to-potent inhibition of lectins LecA and LecB from Pseudomonas aeruginosa. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  8. Endothelial cell markers in vascular neoplasms: an immunohistochemical study comparing factor VIII-related antigen, blood group specific antigens, 6-keto-PGF1 alpha, and Ulex europaeus 1 lectin.

    PubMed

    Little, D; Said, J W; Siegel, R J; Fealy, M; Fishbein, M C

    1986-06-01

    Markers for endothelial cells including Ulex europaeus 1 lectin, blood group A, B, and H, and the prostaglandin metabolite 6-keto-PGF1 alpha were evaluated in paraffin secretions from formalin-fixed benign and malignant vascular neoplasms using a variety of immunohistochemical techniques, and results compared with staining for factor VIII-related antigen. Staining for Ulex appeared more sensitive than factor VIII-related antigen in identifying poorly differentiated neoplasms including haemangiosarcomas and spindle cell proliferations in Kaposi's sarcoma. Staining for blood group related antigens correlated with blood group in all cases. Ulex europaeus 1 lectin was the only marker for endothelial cells in lymphangiomas.

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

    PubMed Central

    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

  10. Psathyrella velutina Mushroom Lectin Exhibits High Affinity toward Sialoglycoproteins Possessing Terminal N-Acetylneuraminic Acid alpha 2,3-Linked to Penultimate Galactose Residues of Trisialyl N-Glycans. Comparison with other sialic acid-specific lectins.

    PubMed

    Ueda, Haruko; Matsumoto, Hanako; Takahashi, Noriko; Ogawa, Haruko

    2002-07-12

    A lectin from the fruiting body of the Psathyrella velutina mushroom (PVL) was found to bind specifically to N-acetylneuraminic acid, as well as to GlcNAc (Ueda, H., Kojima, K., Saitoh, T., and Ogawa, H. (1999) FEBS Lett. 448, 75-80). In this study, the glycan sequences that PVL recognizes with high affinity on sialoglycoproteins were revealed. Among sialic acid-specific lectins only PVL could reveal the sialylated N-acetyllactosamine structure of glycoproteins in blotting studies, based on the dual specificity. The affinity of PVL to fetuin was measured by surface plasmon resonance to be 10(7) m(-1), which is an order of magnitude higher than those of Sambucus nigra agglutinin and Maackia amurensis mitogen, whereas affinity to asialofetuin was approximately 0 and to asialo-agalactofetuin was 10(8) m(-1), suggesting that PVL exhibits remarkably high affinities toward glycoproteins possessing trisialo- or GlcNAc-exposed glycans. Transferrin was separated into fractions that correspond to the sialylation states on an immobilized PVL column. Transferrin-possessing trisialoglycans containing alpha2,3-linked N-acetylneuraminic acid on the beta1,4-linked GlcNAc branch bound to the PVL column and eluted with GlcNAc; those containing only alpha2,6-linked sialic acids were retarded, whereas other transferrin fractions passed through the column. These results indicate that PVL is a lectin with potential for separation and detection of sialoglycoproteins because of its dual specificity toward sialoglycans and GlcNAc exposed glycans.

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

    PubMed

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

    PubMed Central

    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

  13. Mucosal immunogenicity of plant lectins in mice

    PubMed Central

    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

  14. The Lectin Pathway of Complement and Rheumatic Heart Disease

    PubMed Central

    Beltrame, Marcia Holsbach; Catarino, Sandra Jeremias; Goeldner, Isabela; Boldt, Angelica Beate Winter; de Messias-Reason, Iara José

    2014-01-01

    The innate immune system is the first line of host defense against infection and is comprised of humoral and cellular mechanisms that recognize potential pathogens within minutes or hours of entry. The effector components of innate immunity include epithelial barriers, phagocytes, and natural killer cells, as well as cytokines and the complement system. Complement plays an important role in the immediate response against microorganisms, including Streptococcus sp. The lectin pathway is one of three pathways by which the complement system can be activated. This pathway is initiated by the binding of mannose-binding lectin (MBL), collectin 11 (CL-K1), and ficolins (Ficolin-1, Ficolin-2, and Ficolin-3) to microbial surface oligosaccharides and acetylated residues, respectively. Upon binding to target molecules, MBL, CL-K1, and ficolins form complexes with MBL-associated serine proteases 1 and 2 (MASP-1 and MASP-2), which cleave C4 and C2 forming the C3 convertase (C4b2a). Subsequent activation of complement cascade leads to opsonization, phagocytosis, and lysis of target microorganisms through the formation of the membrane-attack complex. In addition, activation of complement may induce several inflammatory effects, such as expression of adhesion molecules, chemotaxis and activation of leukocytes, release of reactive oxygen species, and secretion of cytokines and chemokines. In this chapter, we review the general aspects of the structure, function, and genetic polymorphism of lectin-pathway components and discuss most recent understanding on the role of the lectin pathway in the predisposition and clinical progression of Rheumatic Fever. PMID:25654073

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

    PubMed

    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.

  16. The complete amino acid sequence of echinoidin, a lectin from the coelomic fluid of the sea urchin Anthocidaris crassispina. Homologies with mammalian and insect lectins.

    PubMed

    Giga, Y; Ikai, A; Takahashi, K

    1987-05-05

    The complete amino acid sequence of echinoidin, the proposed name for a lectin from the coelomic fluid of the sea urchin Anthocidaris crassispina, has been determined by sequencing the peptides obtained from tryptic, Staphylococcus aureus V8 protease, chymotryptic, and thermolysin digestions. Echinoidin is a multimeric protein (Giga, Y., Sutoh, K., and Ikai, A. (1985) Biochemistry 24, 4461-4467) whose subunit consists of a total of 147 amino acid residues and one carbohydrate chain attached to Ser38. The molecular weight of the polypeptide without carbohydrate was calculated to be 16,671. Each polypeptide chain contains seven half-cystines, and six of them form three disulfide bonds in the single polypeptide chain (Cys3-Cys14, Cys31-Cys141, and Cys116-Cys132), while Cys2 is involved in an interpolypeptide disulfide linkage. From secondary structure prediction by the method of Chou and Fasman (Chou, P. Y., and Fasman, G. D. (1974) Biochemistry 13, 211-222) the protein appears to be rich in beta-sheet and beta-turn structures and poor in alpha-helical structure. The sequence of the COOH-terminal half of echinoidin is highly homologous to those of the COOH-terminal carbohydrate recognition portions of rat liver mannose-binding protein and several other hepatic lectins. This COOH-terminal region of echinoidin is also homologous to the central portion of the lectin from the flesh fly Sarcophaga peregrina. Moreover, echinoidin contains an Arg-Gly-Asp sequence which has been proposed to be a basic functional unit in cellular recognition proteins.

  17. L-rhamnose-binding lectins (RBLs) in Nile tilapia, Oreochromis niloticus: characterization and expression profiling in mucosal tissues

    USDA-ARS?s Scientific Manuscript database

    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...

  18. Effects of a phytogenic feed additive on susceptibility of channel catfish to Edwardsiella ictaluri and levels of rhamnose binding lectin

    USDA-ARS?s Scientific Manuscript database

    We investigated the effects of a phytogenic feed additive (Digestarom® P.E.P. MGE) on growth performance, disease susceptibility to Edwardsiella ictaluri, and regulation of six rhamnose binding lectin (RBL) genes. Two hundred and fifty juvenile channel catfish (13.4 ± 0.1 g) were allotted to the fo...

  19. Functional characterization of chitin-binding lectin from Solanum integrifolium containing anti-fungal and insecticidal activities.

    PubMed

    Chen, Chang-Shan; Chen, Chun-Yi; Ravinath, Divya Malathy; Bungahot, Agustina; Cheng, Chi-Ping; You, Ren-In

    2018-01-03

    Along with the rapid development of glycomic tools, the study of lectin-carbohydrate interactions has expanded, opening the way for applications in the fields of analytic, diagnostic, and drug delivery. Chitin-binding lectins (CBLs) play roles in immune defense against chitin-containing pathogens. CBLs from species of the Solanaceae family, such as tomato, potato and jimsonweed, display different binding specificities to sugar chains containing poly-N-acetyllactosamine. In this report, CBLs from Solanum integrifolium were isolated by ion exchange chromatography. The fractions showed hemagglutination activity (HA). The recombinant CBL in the 293F cell culture supernatant was able to inhibit the growth of Rhizoctonia solani and Colletotrichum gloeosporioide. Furthermore, the carbohydrate-binding property of CBLs was confirmed with the inhibition of HA. Binding of CBL to Spodoptera frugiperda (sf21) insect cells can partly be inhibited by N-Acetylglucosamine (GlcNAc), which is related to decrease mitochondrial membrane potential of sf21 cells. The results showed that CBL exhibited antifungal properties and inhibited insect cell growth, which is directly correlated to the lectin-carbohydrate interaction. Further identification and characterization of CBLs will help to broaden their scope of application in plant defense and in biomedical applications.

  20. Lectin conjugates as biospecific contrast agents for MRI. Coupling of Lycopersicon esculentum agglutinin to linear water-soluble DTPA-loaded oligomers.

    PubMed

    Pashkunova-Martic, Irena; Kremser, Christian; Galanski, Markus; Schluga, Petra; Arion, Vladimir; Debbage, Paul; Jaschke, Werner; Keppler, Bernhard

    2011-06-01

    Magnetic resonance imaging (MRI) requires synthesis of contrast media bearing targeting groups and numerous gadolinium chelating groups generating high relaxivity. This paper explores the results of linking the gadolinium chelates to the targeting group, a protein molecule, via various types of linkers. Polycondensates of diethylenetriaminepentaacetic acid (DTPA) with either diols or diamines were synthesised and coupled to the targeting group, a lectin (Lycopersicon esculentum agglutinin, tomato lectin) which binds with high affinity to specific oligosaccharide configurations in the endothelial glycocalyx. The polycondensates bear up to four carboxylic groups per constitutive unit. Gd-chelate bonds are created through dative interactions with the unshared pair of electrons on each oxygen and nitrogen atom on DTPA. This is mandatory for complexation of Gd(III) and avoidance of the severe toxicity of free gadolinium ions. The polymer-DTPA compounds were characterised by (1)H NMR and mass spectrometry. The final lectin-DTPA-polycondensate conjugates were purified by fast protein liquid chromatography (FPLC). The capacity for specific binding was assessed, and the MRI properties were examined in order to evaluate the use of these oligomers as components of selective perfusional contrast agents.

  1. Comparative evaluation of several docking tools for docking small molecule ligands to DC-SIGN.

    PubMed

    Jug, Gregor; Anderluh, Marko; Tomašič, Tihomir

    2015-06-01

    Five docking tools, namely AutoDock, FRED, CDOCKER, FlexX and GOLD, have been critically examined, with the aim of selecting those most appropriate for use as docking tools for docking molecules to the lectin dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN). This lectin has been selected for its rather non-druggable binding site, which enables complex interactions that guide the binding of the core monosaccharide. Since optimal orientation is crucial for forming coordination bonds, it was important to assess whether the selected docking tools could reproduce the optimal binding conformation for several oligosaccharides that are known to bind DC-SIGN. Our results show that even widely used docking programs have certain limitations when faced with a rather shallow and featureless binding site, as is the case of DC-SIGN. The FRED docking software (OpenEye Scientific Software, Inc.) was found to score as the best tool for docking ligands to DC-SIGN. The performance of FRED was further assessed on another lectin, Langerin. We have demonstrated that this validated docking protocol could be used for docking to other lectins similar to DC-SIGN.

  2. Lycopersicon esculentum lectin is a marker of transient amplifying cells in in vitro cultures of isolated limbal stem cells.

    PubMed

    Vergallo, C; Fonseca, T; Pizzi, G; Dini, L

    2010-08-01

    The maintenance of a healthy corneal epithelium under both normal and wound healing conditions is achieved by a population of stem cells (SCs) located in the basal epithelium at the corneoscleral limbus. In the light of the development of strategies for reconstruction of the ocular surface in patients with limbal stem cell deficiency, a major challenge in corneal SCs biology remains the ability to identify stem cells in situ and in vitro. To date, not so much markers exist for the identification of different phenotypes. CESCs (corneal epithelial stem cells) isolated from limbal biopsies were maintained in primary culture for 14 days and stained with Hoechst and a panel of FITC-conjugated lectins. All lectins, with the exception of Lycopersicon esculentum, labelled CESCs irrespective of the degree of differentiation. Lycopersicon esculentum, that binds N-acetylglucosamine oligomers, labelled intensely only the surface of TACs (single corneal epithelial stem cells better than colonial cells). These results suggest that Lycopersicon esculentum lectin is a useful and easy-to-use marker for the in vitro identification of TACs (transient amplifying cells) in cultures of isolated CESCs. Copyright 2010. Published by Elsevier Ltd.

  3. Lectin-binding histochemistry of non-decalcified growth plate cartilage: a postembedment method for light microscopy of epon-embedded tissue.

    PubMed

    Farnum, C E; Wilsman, N J

    1984-06-01

    A postembedment method for the localization of lectin-binding glycoconjugates was developed using Epon-embedded growth plate cartilage from Yucatan miniature swine. By testing a variety of etching, blocking, and incubation procedures, a standard protocol was developed for 1 micron thick sections that allowed visualization of both intracellular and extracellular glycoconjugates with affinity for wheat germ agglutinin and concanavalin A. Both fluorescent and peroxidase techniques were used, and comparisons were made between direct methods and indirect methods using the biotin-avidin bridging system. Differential extracellular lectin binding allowed visualization of interterritorial , territorial, and pericellular matrices. Double labeling experiments showed the precision with which intracellular binding could be localized to specific cytoplasmic compartments, with resolution of binding to the Golgi apparatus, endoplasmic reticulum, and nuclear membrane at the light microscopic level. This method allows the localization of both intracellular and extracellular lectin-binding glycoconjugates using fixation and embedment procedures that are compatible with simultaneous ultrastructural analysis. As such it should have applicability both to the morphological analysis of growth plate organization during normal endochondral ossification, as well as to the diagnostic pathology of matrix abnormalities in disease states of growing cartilage.

  4. A lectin receptor kinase as a potential sensor for extracellular nicotinamide adenine dinucleotide in Arabidopsis thaliana

    PubMed Central

    Wang, Chenggang; Zhou, Mingqi; Zhang, Xudong; Yao, Jin; Zhang, Yanping; Mou, Zhonglin

    2017-01-01

    Nicotinamide adenine dinucleotide (NAD+) participates in intracellular and extracellular signaling events unrelated to metabolism. In animals, purinergic receptors are required for extracellular NAD+ (eNAD+) to evoke biological responses, indicating that eNAD+ may be sensed by cell-surface receptors. However, the identity of eNAD+-binding receptors still remains elusive. Here, we identify a lectin receptor kinase (LecRK), LecRK-I.8, as a potential eNAD+ receptor in Arabidopsis. The extracellular lectin domain of LecRK-I.8 binds NAD+ with a dissociation constant of 436.5 ± 104.8 nM, although much higher concentrations are needed to trigger in vivo responses. Mutations in LecRK-I.8 inhibit NAD+-induced immune responses, whereas overexpression of LecRK-I.8 enhances the Arabidopsis response to NAD+. Furthermore, LecRK-I.8 is required for basal resistance against bacterial pathogens, substantiating a role for eNAD+ in plant immunity. Our results demonstrate that lectin receptors can potentially function as eNAD+-binding receptors and provide direct evidence for eNAD+ being an endogenous signaling molecule in plants. DOI: http://dx.doi.org/10.7554/eLife.25474.001 PMID:28722654

  5. Electrochemical lectin based biosensors as a label-free tool in glycomics

    PubMed Central

    Bertók, Tomáš; Katrlík, Jaroslav; Gemeiner, Peter; Tkac, Jan

    2016-01-01

    Glycans and other saccharide moieties attached to proteins and lipids, or present on the surface of a cell, are actively involved in numerous physiological or pathological processes. Their structural flexibility (that is based on the formation of various kinds of linkages between saccharides) is making glycans superb “identity cards”. In fact, glycans can form more “words” or “codes” (i.e., unique sequences) from the same number of “letters” (building blocks) than DNA or proteins. Glycans are physicochemically similar and it is not a trivial task to identify their sequence, or - even more challenging - to link a given glycan to a particular physiological or pathological process. Lectins can recognise differences in glycan compositions even in their bound state and therefore are most useful tools in the task to decipher the “glycocode”. Thus, lectin-based biosensors working in a label-free mode can effectively complement the current weaponry of analytical tools in glycomics. This review gives an introduction into the area of glycomics and then focuses on the design, analytical performance, and practical utility of lectin-based electrochemical label-free biosensors for the detection of isolated glycoproteins or intact cells. PMID:27239071

  6. Processing, targeting, and antifungal activity of stinging nettle agglutinin in transgenic tobacco.

    PubMed

    Does, M P; Houterman, P M; Dekker, H L; Cornelissen, B J

    1999-06-01

    The gene encoding the precursor to stinging nettle (Urtica dioica L. ) isolectin I was introduced into tobacco (Nicotiana tabacum). In transgenic plants this precursor was processed to mature-sized lectin. The mature isolectin is deposited intracellularly, most likely in the vacuoles. A gene construct lacking the C-terminal 25 amino acids was also introduced in tobacco to study the role of the C terminus in subcellular trafficking. In tobacco plants that expressed this construct, the mutant precursor was correctly processed and the mature isolectin was targeted to the intercellular space. These results indicate the presence of a C-terminal signal for intracellular retention of stinging nettle lectin and most likely for sorting of the lectin to the vacuoles. In addition, correct processing of this lectin did not depend on vacuolar deposition. Isolectin I purified from tobacco displayed identical biological activities as isolectin I isolated from stinging nettle. In vitro antifungal assays on germinated spores of the fungi Botrytis cinerea, Trichoderma viride, and Colletotrichum lindemuthianum revealed that growth inhibition by stinging nettle isolectin I occurs at a specific phase of fungal growth and is temporal, suggesting that the fungi had an adaptation mechanism.

  7. PNA lectin for purifying mouse acinar cells from the inflamed pancreas.

    PubMed

    Xiao, Xiangwei; Fischbach, Shane; Fusco, Joseph; Zimmerman, Ray; Song, Zewen; Nebres, Philip; Ricks, David Matthew; Prasadan, Krishna; Shiota, Chiyo; Husain, Sohail Z; Gittes, George K

    2016-02-17

    Better methods for purifying human or mouse acinar cells without the need for genetic modification are needed. Such techniques would be advantageous for the specific study of certain mechanisms, such as acinar-to-beta-cell reprogramming and pancreatitis. Ulex Europaeus Agglutinin I (UEA-I) lectin has been used to label and isolate acinar cells from the pancreas. However, the purity of the UEA-I-positive cell fraction has not been fully evaluated. Here, we screened 20 widely used lectins for their binding specificity for major pancreatic cell types, and found that UEA-I and Peanut agglutinin (PNA) have a specific affinity for acinar cells in the mouse pancreas, with minimal affinity for other major pancreatic cell types including endocrine cells, duct cells and endothelial cells. Moreover, PNA-purified acinar cells were less contaminated with mesenchymal and inflammatory cells, compared to UEA-I purified acinar cells. Thus, UEA-I and PNA appear to be excellent lectins for pancreatic acinar cell purification. PNA may be a better choice in situations where mesenchymal cells or inflammatory cells are significantly increased in the pancreas, such as type 1 diabetes, pancreatitis and pancreatic cancer.

  8. PNA lectin for purifying mouse acinar cells from the inflamed pancreas

    PubMed Central

    Xiao, Xiangwei; Fischbach, Shane; Fusco, Joseph; Zimmerman, Ray; Song, Zewen; Nebres, Philip; Ricks, David Matthew; Prasadan, Krishna; Shiota, Chiyo; Husain, Sohail Z.; Gittes, George K.

    2016-01-01

    Better methods for purifying human or mouse acinar cells without the need for genetic modification are needed. Such techniques would be advantageous for the specific study of certain mechanisms, such as acinar-to-beta-cell reprogramming and pancreatitis. Ulex Europaeus Agglutinin I (UEA-I) lectin has been used to label and isolate acinar cells from the pancreas. However, the purity of the UEA-I-positive cell fraction has not been fully evaluated. Here, we screened 20 widely used lectins for their binding specificity for major pancreatic cell types, and found that UEA-I and Peanut agglutinin (PNA) have a specific affinity for acinar cells in the mouse pancreas, with minimal affinity for other major pancreatic cell types including endocrine cells, duct cells and endothelial cells. Moreover, PNA-purified acinar cells were less contaminated with mesenchymal and inflammatory cells, compared to UEA-I purified acinar cells. Thus, UEA-I and PNA appear to be excellent lectins for pancreatic acinar cell purification. PNA may be a better choice in situations where mesenchymal cells or inflammatory cells are significantly increased in the pancreas, such as type 1 diabetes, pancreatitis and pancreatic cancer. PMID:26884345

  9. Identification of natural killer cell receptor clusters in the platypus genome reveals an expansion of C-type lectin genes.

    PubMed

    Wong, Emily S W; Sanderson, Claire E; Deakin, Janine E; Whittington, Camilla M; Papenfuss, Anthony T; Belov, Katherine

    2009-08-01

    Natural killer (NK) cell receptors belong to two unrelated, but functionally analogous gene families: the immunoglobulin superfamily, situated in the leukocyte receptor complex (LRC) and the C-type lectin superfamily, located in the natural killer complex (NKC). Here, we describe the largest NK receptor gene expansion seen to date. We identified 213 putative C-type lectin NK receptor homologs in the genome of the platypus. Many have arisen as the result of a lineage-specific expansion. Orthologs of OLR1, CD69, KLRE, CLEC12B, and CLEC16p genes were also identified. The NKC is split into at least two regions of the genome: 34 genes map to chromosome 7, two map to a small autosome, and the remainder are unanchored in the current genome assembly. No NK receptor genes from the LRC were identified. The massive C-type lectin expansion and lack of Ig-domain-containing NK receptors represents the most extreme polarization of NK receptors found to date. We have used this new data from platypus to trace the possible evolutionary history of the NK receptor clusters.

  10. Processing, Targeting, and Antifungal Activity of Stinging Nettle Agglutinin in Transgenic Tobacco

    PubMed Central

    Does, Mirjam P.; Houterman, Petra M.; Dekker, Henk L.; Cornelissen, Ben J.C.

    1999-01-01

    The gene encoding the precursor to stinging nettle (Urtica dioica L.) isolectin I was introduced into tobacco (Nicotiana tabacum). In transgenic plants this precursor was processed to mature-sized lectin. The mature isolectin is deposited intracellularly, most likely in the vacuoles. A gene construct lacking the C-terminal 25 amino acids was also introduced in tobacco to study the role of the C terminus in subcellular trafficking. In tobacco plants that expressed this construct, the mutant precursor was correctly processed and the mature isolectin was targeted to the intercellular space. These results indicate the presence of a C-terminal signal for intracellular retention of stinging nettle lectin and most likely for sorting of the lectin to the vacuoles. In addition, correct processing of this lectin did not depend on vacuolar deposition. Isolectin I purified from tobacco displayed identical biological activities as isolectin I isolated from stinging nettle. In vitro antifungal assays on germinated spores of the fungi Botrytis cinerea, Trichoderma viride, and Colletotrichum lindemuthianum revealed that growth inhibition by stinging nettle isolectin I occurs at a specific phase of fungal growth and is temporal, suggesting that the fungi had an adaptation mechanism. PMID:10364393

  11. The galactose-binding lectin isolated from Bauhinia bauhinioides Mart seeds inhibits neutrophil rolling and adhesion via primary cytokines.

    PubMed

    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 carrageenan peritoneal neutrophil migration (51%), leukocyte rolling (58%) and adhesion (68%) and the neutrophil migration induced by TNF-α (64%). These effects were reversed by the association of BBL with galactose, demonstrating that the carbohydrate-binding domain is essential for lectin activity. In addition, BBL reduced myeloperoxidase activity (84%) and TNF-α (68%) and IL1-β (47%) levels. In conclusion, the present investigation demonstrated that BBL contains highly homologous isolectins, resulting in a total of 86 amino acid residues, and exhibits anti-inflammatory activity by inhibiting neutrophil migration by reducing TNF-α and IL1-β levels via the lectin domain. Copyright © 2015 John Wiley & Sons, Ltd.

  12. A lectin histochemical study on carbohydrate moieties of the gonadotropin-like substance in the epithelial cells of Hatschek's pit of Branchiostoma belcheri

    NASA Astrophysics Data System (ADS)

    Fang, Y. Q.; Welsch, U.

    1997-03-01

    The present light microscopic lectin, histochemical study suggests for the first time that the vertebrate gonadotropin-like substance in the basal part of the epithelial cells of Hatschek's pit is a sialic acid-containing glycoprotein. The binding intensity of the epithelial cells in Hatschek's pit to 6 lectins ( Limulus polyphemus agglutinin (LPA), Wheat germ agglutinin (WGA), Helix pomatia agglutinin (HPA), Concanavalin A (Con A), Ulex europaeus agglutinin I (UEA I) and Ricinus communis agglutinin I (RCA I)) indicate that the carbohydrate composition of the gonadotrophic glycoprotein is similar to that of mammals and fish, and that N-acetyl-D-galactosamine, sialic acid, glucosamine, D-mannose and L-fucose are components of the carbohydrate portion.

  13. Plant Lectins as Medical Tools against Digestive System Cancers

    PubMed Central

    Estrada-Martínez, Laura Elena; Cervantes-Jiménez, Ricardo; Ferriz-Martínez, Roberto Augusto; Blanco-Labra, Alejandro

    2017-01-01

    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. PMID:28671623

  14. 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.

    PubMed

    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 production of pro-inflammatory and anti-inflammatory cytokines, showing differential but complementary profiles. Moreover, when compared with non-treated mice, the parasite burden was significantly lower and survival rates higher in mice treated with ScLL or ScLL plus ArtinM, similarly with sulfadiazine treatment. In conclusion, the results demonstrated the suitable potential immunotherapeutic effect of ScLL and ArtinM lectins to control acute toxoplasmosis in this experimental murine model.

  15. 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

    PubMed Central

    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 production of pro-inflammatory and anti-inflammatory cytokines, showing differential but complementary profiles. Moreover, when compared with non-treated mice, the parasite burden was significantly lower and survival rates higher in mice treated with ScLL or ScLL plus ArtinM, similarly with sulfadiazine treatment. In conclusion, the results demonstrated the suitable potential immunotherapeutic effect of ScLL and ArtinM lectins to control acute toxoplasmosis in this experimental murine model. PMID:27933277

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

    Yang, Yongil; Labbé, Jessy; Muchero, Wellington

    Receptor-like kinases (RLKs) belong to a large protein family with over 600 members in Arabidopsis and over 1000 in rice. Among RLKs, the lectin receptor-like kinases (LecRLKs) possess a characteristic extracellular carbohydrate-binding lectin domain and play important roles in plant development and innate immunity. In addition, there are 75 and 173 LecRLKs in Arabidopsis and rice, respectively. However, little is known about LecRLKs in perennial woody plants.

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

    PubMed

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

    2001-02-01

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

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

    PubMed Central

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

    2001-01-01

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

  19. Identification and Characterization of Prostate Cancer Associated Protein Biomarkers Using High-Throughput Mass Spectrometry

    DTIC Science & Technology

    2006-09-01

    Specific examples using serum samples from prostate cancer and hepatocellular carcinoma subjects are provided, along with suggested experimental...from prostate cancer and hepatocellular carcinoma subjects are provided, along with suggested experimental strategies for integration of lectin based...application of different lectins to enrich for serum glycoforms found in sera from prostate cancer and hepatocellular carcinoma subjects. For the

  20. Functional evaluation of carbohydrate-centred glycoclusters by enzyme-linked lectin assay: ligands for concanavalin A.

    PubMed

    Köhn, Maja; Benito, Juan M; Ortiz Mellet, Carmen; Lindhorst, Thisbe K; García Fernández, José M

    2004-06-07

    The affinities of the mannose-specific lectin concanavalin A (Con A) towards D-glucose-centred mannosyl clusters differing in the anomeric configuration of the monosaccharide core, nature of the bridging functional groups and valency, have been measured by a competitive enzyme-linked lectin assay. Pentavalent thioether-linked ligands (5 and 7) were prepared by radical addition of 2,3,4,6-tetra-O-acetyl-1-thio-alpha-D-mannopyranose to the corresponding penta-O-allyl-alpha- or -beta-D-glucopyranose, followed by deacetylation. The distinct reactivity of the anomeric position in the D-glucose scaffold was exploited in the preparation of a tetravalent cluster (10) that keeps a reactive aglyconic group for further manipulation, including incorporation of a reporter group or attachment to a solid support. Hydroboration of the double bonds in the penta-O-allyl-alpha-D-glucopyranose derivative and replacement of the hydroxy groups with amine moieties gave a suitable precursor for the preparation of pentavalent and 15-valent mannosides through the thiourea-bridging reaction (17 and 20, respectively). The diastereomeric 1-thiomannose-coated clusters 5 and 7 were demonstrated to be potent ligands for Con A, with IC(50) values for the inhibition of the Con A-yeast mannan association indicative of 6.4- and 5.5-fold increases in binding affinity (valency-corrected values), respectively, relative to the value for methyl alpha-D-mannopyranoside. The tetravalent cluster 10 exhibited a valency-corrected relative lectin-binding potency virtually identical to that of the homologous pentavalent mannoside 7. In sharp contrast, replacement of the 1-thiomannose wedges of 5 with alpha-D-mannopyranosylthioureido units (17) virtually abolished any multivalent or statistic effects, with a dramatic decrease of binding affinity. The 15-valent ligand 20, possessing classical O-glycosidic linkages, exhibited a twofold increase in lectin affinity relative to the penta-O-(thioglycoside) 5; it is less efficient based on the number of mannose units. The results illustrate the potential of carbohydrates as polyfunctional platforms for glycocluster construction and underline the importance of careful design of the overall architecture in optimising glycocluster recognition by specific lectins.

  1. Characterizing the glycocalyx of poultry spermatozoa: III. Semen cryopreservation methods alter the carbohydrate component of rooster sperm membrane glycoconjugates.

    PubMed

    Peláez, J; Bongalhardo, D C; Long, J A

    2011-02-01

    The carbohydrate-rich zone on the sperm surface is essential for inmunoprotection in the female tract and early gamete interactions. We recently have shown the glycocalyx of chicken sperm to be extensively sialylated and to contain residues of mannose, glucose, galactose, fucose, N-acetyl-galactosamine, N-acetyl-glucosamine, and N-acetyl-lactosamine. Our objective here was to evaluate the effects of 3 different cryopreservation methods on the sperm glycocalyx. Semen from roosters was pooled, diluted, cooled to 5°C, and aliquoted for cryopreservation using 6% dimethylacetamide (DMA), 11% dimethylsulfoxide (DMSO), or 11% glycerol (GOH). For the DMA method, semen was equilibrated for 1 min with cryoprotectant and rapidly frozen by dropping 25-µL aliquots into liquid nitrogen. For the other methods, semen was equilibrated for either 1 min (DMSO) or 20 min (GOH), loaded into straws, and frozen with a programmable freezer. Thawing rates mimicked the freezing rates (e.g., rapid for DMA; moderate for DMSO and GOH). Aliquots of thawed and fresh, unfrozen semen were incubated with 1 of 12 fluorescein isothiocyanate-conjugated lectins and counterstained with propidium iodide, and mean fluorescence intensity (MFI) was assessed by flow cytometry. For each lectin, the MFI of propidium iodide-negative (viable sperm) was compared among the fresh and frozen-thawed treatments (n = 5). For sperm frozen with GOH and DMA, the MFI of most lectins was similar (P > 0.05) to that of fresh sperm, whereas only 5 of 12 lectins were similar between fresh and DMSO-frozen sperm. Sperm from all 3 methods had higher (P < 0.05) MFI for lectins specific for N-acetyl-glucosamine and β-galactose than did fresh sperm. Fewer sperm were damaged (P < 0.001) with GOH than with DMA or DMSO, and membrane integrity was correlated with MFI for 9 of 12 lectins (P < 0.05). These data indicate that surface carbohydrates are altered during cryopreservation, and that cryoprotectant type and freezing-thawing rates affect the degree of modification. Although the glycoconjugates have not yet been identified, it is likely that these cryopreservation-induced changes contribute to the reduced fertility of frozen-thawed chicken semen.

  2. Mistletoe lectin I in complex with galactose and lactose reveals distinct sugar-binding properties

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

    Mikeska, Ruth; Wacker, Roland; Arni, Raghuvir

    2005-01-01

    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{sub free} = 23.6%) and 20.9 (R{sub 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-chainmore » 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.« less

  3. Ectopic Expression of GsSRK in Medicago sativa Reveals Its Involvement in Plant Architecture and Salt Stress Responses.

    PubMed

    Sun, Mingzhe; Qian, Xue; Chen, Chao; Cheng, Shufei; Jia, Bowei; Zhu, Yanming; Sun, Xiaoli

    2018-01-01

    Receptor-like kinases (RLK) play fundamental roles in plant growth and stress responses. Compared with other RLKs, little information is provided concerning the S-locus LecRLK subfamily, which is characterized by an extracellular G-type lectin domain and an S-locus-glycop domain. Until now, the function of the G-type lectin domain is still unknown. In a previous research, we identified a Glycine soja S-locus LecRLK gene GsSRK , which conferred increased salt stress tolerance in transgenic Arabidopsis . In this study, to investigate the role of the G-type lectin domain and to breed transgenic alfalfa with superior salt stress tolerance, we transformed the full-length GsSRK ( GsSRK-f ) and a truncated version of GsSRK ( GsSRK-t ) deleting the G-type lectin domain into alfalfa. Our results showed that overexpression of GsSRK-t , but not GsSRK-f , resulted in changes of plant architecture, as evidenced by more branches but shorter shoots of GsSRK-t transgenic alfalfa, indicating a potential role of the extracellular G-type lectin domain in regulating plant architecture. Furthermore, we also found that transgenic alfalfa overexpressing either GsSRK-f or GsSRK-t showed increased salt stress tolerance, and GsSRK-t transgenic alfalfa displayed better growth (more branches and higher fresh weight) than GsSRK-f lines under salt stress. In addition, our results suggested that both GsSRK-f and GsSRK-t were involved in ion homeostasis, ROS scavenging, and osmotic regulation. Under salt stress, the Na + content in the transgenic lines was significantly lower, while the K + content was slightly higher than that in WT. Moreover, the transgenic lines displayed reduced ion leakage and MDA content, but increased SOD activity and proline content than WT. Notably, no obvious difference in these physiological indices was observed between GsSRK-f and GsSRK-t transgenic lines, implying that deletion of the GsSRK G-type lectin domain does not affect its physiological function in salt stress responses. In conclusion, results in this research reveal the dual role of GsSRK in regulating both plant architecture and salt stress responses.

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

    PubMed

    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.

  5. A Nanoparticle-Lectin Immunoassay Improves Discrimination of Serum CA125 from Malignant and Benign Sources.

    PubMed

    Gidwani, Kamlesh; Huhtinen, Kaisa; Kekki, Henna; van Vliet, Sandra; Hynninen, Johanna; Koivuviita, Niina; Perheentupa, Antti; Poutanen, Matti; Auranen, Annika; Grenman, Seija; Lamminmäki, Urpo; Carpen, Olli; van Kooyk, Yvette; Pettersson, Kim

    2016-10-01

    Measurement of serum cancer antigen 125 (CA125) is the standard approach for epithelial ovarian cancer (EOC) diagnostics and follow-up. However, the clinical specificity is not optimal because increased values are also detected in healthy controls and in benign diseases. CA125 is known to be differentially glycosylated in EOC, potentially offering a way to construct CA125 assays with improved cancer specificity. Our goal was to identify carbohydrate-reactive lectins for discriminating between CA125 originating from EOC and noncancerous sources. CA125 from the OVCAR-3 cancer cell line, placental homogenate, and ascites fluid from patients with cirrhosis were captured on anti-CA125 antibody immobilized on microtitration wells. A panel of lectins, each coated onto fluorescent europium-chelate-doped 97-nm nanoparticles (Eu(+3)-NPs), was tested for detection of the immobilized CA125. Serum samples from high-grade serous EOC or patients with endometriosis and healthy controls were analyzed. By using macrophage galactose-type lectin (MGL)-coated Eu(+3)-NPs, an analytically sensitive CA125 assay (CA125(MGL)) was achieved that specifically recognized the CA125 isoform produced by EOC, whereas the recognition of CA125 from nonmalignant conditions was reduced. Serum CA125(MGL) measurement better discriminated patients with EOC from endometriosis compared to conventional immunoassay. The discrimination was particularly improved for marginally increased CA125 values and for earlier detection of EOC progression. The new CA125(MGL) assay concept could help reduce the false-positive rates of conventional CA125 immunoassays. The improved analytical specificity of this test approach is dependent on a discriminating lectin immobilized in large numbers on Eu(+3)-NPs, providing both an avidity effect and signal amplification. © 2016 American Association for Clinical Chemistry.

  6. Changes in the levels of mannan-binding lectin and ficolins during head-down tilted bed rest.

    PubMed

    Kelsen, Jens; Sandahl, Thomas D; Storm, Line; Frings-Meuthen, Petra; Dahlerup, Jens F; Thiel, Steffen

    2014-08-01

    Spaceflight studies and ground-based analogues of microgravity indicate a weakening of human immunity. Mannan-binding lectin (MBL) and H-, L-, and M-ficolin together constitute the lectin pathway and mediate the clearance of pathogens through complement activation. We hypothesized that simulated microgravity may weaken human innate immune functions and studied the impact of 6° head-down tilted bed rest (HDT) for 21 d on MBL and ficolin levels. Within a 6-mo period, seven men underwent two periods of HDT. Blood samples were analyzed for MBL, H-, L-, and M-ficolin, mannose-binding lectin-associated protein of 44 kDa (MAp44), and collectin liver 1 (CL-L1) by time-resolved immunofluorometric assays (TRIFMA). We observed well-defined individual preintervention levels of MBL and ficolins. Remarkably similar intraindividual changes occurred for MBL and MBL levels decreased (mean 282 ng · ml⁻¹) in the recovery phase. Conversely, CL-L1, a protein with MBL-like properties, increased (mean 102 ng · ml⁻¹) during the recovery phase. M-ficolin increased (mean 79 ng · ml⁻¹) within the first 2 d of HDT, followed by a decrease (mean 112 ng · ml⁻¹) during the recovery phase. L-ficolin increased (mean 304 ng · ml⁻¹) during HDT, while H-ficolin was essentially unaffected. MAp44, a down-regulator of the lectin pathway, decreased initially (mean 78 ng · ml⁻¹) in the recovery phase followed by an increase (mean 131 ng · ml⁻¹). Alterations in MBL and ficolin levels were modest and with our current knowledge do not lead to overt immunodeficiency. Pronounced changes occurred when the subjects resumed the upright position. In selected individuals, these changes appear to be a conserved response to HDT.

  7. Lectin-carbohydrate recognition mechanism of Plasmodium berghei in the midgut of malaria vector Anopheles stephensi using quantum dot as a new approach.

    PubMed

    Basseri, Hamid R; Javazm, Mahdi Salari; Farivar, Leila; Abai, Mohammad R

    2016-04-01

    Potential targets of Plasmodium ookinetes at the mosquito midgut walls were investigated in relation to interfering malarial transmission. In this study, the essential application of Quantum Dots (QDs) was used to examine the interaction between Plasmodium berghei ookinetes and the Anopheles stephensi midgut, based on lectin-carbohydrate recognition. Two significant lectins were utilized to determine this interaction. Two QDs, cadmium telluride (CdTe)/CdS and cadmium selenide (CdSe)/CdS, were employed in staining Plasmodium ookinete to study its interaction in the midgut of the mosquito vector in vivo. Concurrently, two lectins, wheat germ agglutinin (WGA) and concanavalin A (Con A), were inadvertently exploited to mask lectin binding sites between ookinetes and mosquito midgut cells. The numbers of ookinetes in both lumen and epithelial cells were eventually counted, following adequate preparation of wax sections extracted from whole midgut, and subsequent examination using a differential interference contrast a fluorescence microscopic technique. Interestingly, we detected that neither of the QDs mutated ookinete invasion into the midgut cells of the investigated mosquitoes. QD staining of ookinetes remained permanent despite the effective embedding procedure. The massive binding potency of ookinetes to midgut cells of the cross-examined mosquitoes undoubtedly revealed that Con A did not interrupt ookinete penetration into the midgut wall. In contrast, WGA inhibited ookinete invasion into the midgut cells. The results proved that QD nanoparticles are biocompatible, non-toxic to P. berghei and stable to photobleaching. The QDs staining, which was successfully implemented for ookinete labelling, is a simple and effective tool which plays a crucial role in bioimaging including the study of parasite-vector interactions. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. The first trimeric Galanthus nivalis agglutinin-related lectin of Orchidaceae was found in Dendrobium pendulum: purification, characterization, and effects of stress factors.

    PubMed

    Siripipatthana, Patthraporn; Phaonakrop, Narumon; Roytrakul, Sittiruk; Senawong, Gulsiri; Mudalige-Jayawickrama, Rasika G; Sattayasai, Nison

    2015-07-01

    Trimeric Galanthus nivalis agglutinin-related lectin of Orchidaceae with two conformational forms was first studied in Dendrobium pendulum . It was highly expressed by stress factors. Using mannan-agarose column chromatography, a mannose-binding protein was purified from Dendrobium pendulum Roxb. pseudobulb. After heating in the presence of sodium dodecyl sulfate (SDS) with or without 2-mercaptoethanol, the protein showed one band with molecular mass of 14.0 kDa on SDS-polyacrylamide gel electrophoresis (PAGE). Without heating, three bands were found at positions of 14.0, 39.4, and 41.5 kDa, but a higher amount of 39.4 and 41.5 kDa protein bands were seen in the presence of 2-mercaptoethanol. Liquid chromatography-tandem mass spectrometry and database search indicated that the 14.0 kDa protein band contained three peptide fragments identical to parts of a lectin precursor from Dendrobiu m findleyanum Parish & Rchb.f. Native-PAGE and Ferguson plot showed that the purified protein had two native forms with molecular masses of 44.2 and 45.3 kDa, indicating three 14.0 kDa polypeptide subunits. The purified protein exhibited the agglutination activity with trypsinized chicken erythrocytes. It was then recognized as a Galanthus nivalis agglutinin-related lectin and named D. pendulum agglutinin (DPA). Using reverse transcription-polymerase chain reaction and DNA sequencing, the deduced amino acid sequence of DPA precursor showed the highest homology (96.4%) with a lectin precursor of D. findleyanum and contained three mannose-binding sites. Greater amounts of DPA were found when the pseudobulbs were treated with stress factors including ultraviolet light, abscisic acid, hydrogen peroxide, and acetylene gas.

  9. Lectins Offer New Perspectives in the Development of Macrophage-Targeted Therapies for COPD/Emphysema

    PubMed Central

    Mukaro, Violet R.; Bylund, Johan; Hodge, Greg; Holmes, Mark; Jersmann, Hubertus; Reynolds, Paul N.; Hodge, Sandra

    2013-01-01

    We have previously shown that the defective ability of alveolar macrophages (AM) to phagocytose apoptotic cells (‘efferocytosis’) in chronic obstructive pulmonary disease/emphysema (COPD) could be therapeutically improved using the C-type lectin, mannose binding lectin (MBL), although the exact mechanisms underlying this effect are unknown. An S-type lectin, galectin-3, is also known to regulate macrophage phenotype and function, via interaction with its receptor CD98. We hypothesized that defective expression of galectin/CD98 would be associated with defective efferocytosis in COPD and that mechanisms would include effects on cytoskeletal remodeling and macrophage phenotype and glutathione (GSH) availability. Galectin-3 was measured by ELISA in BAL from controls, smokers and current/ex-smokers with COPD. CD98 was measured on AM using flow cytometry. We assessed the effects of galectin-3 on efferocytosis, CD98, GSH, actin polymerisation, rac activation, and the involvement of PI3K (using β-actin probing and wortmannin inhibition) in vitro using human AM and/or MH-S macrophage cell line. Significant decreases in BAL galectin-3 and AM CD98 were observed in BAL from both current- and ex-smoker COPD subjects vs controls. Galectin 3 increased efferocytosis via an increase in active GTP bound Rac1. This was confirmed with β-actin probing and the role of PI3K was confirmed using wortmannin inhibition. The increased efferocytosis was associated with increases in available glutathione and expression of CD98. We provide evidence for a role of airway lectins in the failed efferocytosis in COPD, supporting their further investigation as potential macrophage-targeted therapies. PMID:23441163

  10. Quantitative analysis of aberrant protein glycosylation in liver cancer plasma by AAL-enrichment and MRM mass spectrometry.

    PubMed

    Ahn, Yeong Hee; Shin, Park Min; Kim, Yong-Sam; Oh, Na Ree; Ji, Eun Sun; Kim, Kwang Hoe; Lee, Yeon Jung; Kim, Sung Ho; Yoo, Jong Shin

    2013-11-07

    A lectin-coupled mass spectrometry (MS) approach was employed to quantitatively monitor aberrant protein glycosylation in liver cancer plasma. To do this, we compared the difference in the total protein abundance of a target glycoprotein between hepatocellular carcinoma (HCC) plasmas and hepatitis B virus (HBV) plasmas, as well as the difference in lectin-specific protein glycoform abundance of the target glycoprotein. Capturing the lectin-specific protein glycoforms from a plasma sample was accomplished by using a fucose-specific aleuria aurantia lectin (AAL) immobilized onto magnetic beads via a biotin-streptavidin conjugate. Following tryptic digestion of both the total plasma and its AAL-captured fraction of each HCC and HBV sample, targeted proteomic mass spectrometry was conducted quantitatively by a multiple reaction monitoring (MRM) technique. From the MRM-based analysis of the total plasmas and AAL-captured fractions, differences between HCC and HBV plasma groups in fucosylated glycoform levels of target glycoproteins were confirmed to arise from both the change in the total protein abundance of the target proteins and the change incurred by aberrant fucosylation on target glycoproteins in HCC plasma, even when no significant change occurs in the total protein abundance level. Combining the MRM-based analysis method with the lectin-capturing technique proved to be a successful means of quantitatively investigating aberrant protein glycosylation in cancer plasma samples. Additionally, it was elucidated that the differences between HCC and control groups in fucosylated biomarker candidates A1AT and FETUA mainly originated from an increase in fucosylation levels on these target glycoproteins, rather than an increase in the total protein abundance of the target glycoproteins.

  11. Puncture mechanics of cnidarian cnidocysts: a natural actuator

    PubMed Central

    Oppegard, Shawn C; Anderson, Peter A; Eddington, David T

    2009-01-01

    Background Cnidocysts isolated from cnidarian organisms are attractive as a drug-delivery platform due to their fast, efficient delivery of toxins. The cnidocyst could be utilized as the means to deliver therapeutics in a wearable drug-delivery patch. Cnidocysts have been previously shown to discharge upon stimulation via electrical, mechanical, and chemical pathways. Cnidocysts isolated from the Portuguese Man O' War jellyfish (Physalia physalis) are attractive for this purpose because they possess relatively long threads, are capable of puncturing through hard fish scales, and are stable for years. Results As a first step in using cnidocysts as a functional component of a drug delivery system, the puncture mechanics of the thread were characterized. Tentacle-contained cnidocysts were used as a best-case scenario due to physical immobilization of the cnidocysts within the tentacle. Ex vivo tentacle-contained cnidocysts from Physalia possessed an elastic modulus puncture threshold of approximately 1-2 MPa, based on puncture tests of materials with a gamut of hardness. Also, a method for inducing discharge of isolated cnidocysts was found, utilizing water as the stimulant. Preliminary lectin-binding experiments were performed using fluorophore-conjugated lectins as a possible means to immobilize the isolated cnidocyst capsule, and prevent reorientation upon triggering. Lectins bound homogeneously to the surface of the capsule, suggesting the lectins could be used for cnidocyst immobilization but not orientation. Conclusion Cnidocysts were found to puncture materials up to 1 MPa in hardness, can be discharged in a dry state using water as a stimulant, and bind homogeneously to lectins, a potential means of immobilization. The information gained from this preliminary work will aid in determining the materials and design of the patch that could be used for drug delivery. PMID:19785761

  12. Mechanism of allosteric propagation across a β-sheet structure investigated by molecular dynamics simulations.

    PubMed

    Interlandi, Gianluca; Thomas, Wendy E

    2016-07-01

    The bacterial adhesin FimH consists of an allosterically regulated mannose-binding lectin domain and a covalently linked inhibitory pilin domain. Under normal conditions, the two domains are bound to each other, and FimH interacts weakly with mannose. However, under tensile force, the domains separate and the lectin domain undergoes conformational changes that strengthen its bond with mannose. Comparison of the crystallographic structures of the low and the high affinity state of the lectin domain reveals conformational changes mainly in the regulatory inter-domain region, the mannose binding site and a large β sheet that connects the two distally located regions. Here, molecular dynamics simulations investigated how conformational changes are propagated within and between different regions of the lectin domain. It was found that the inter-domain region moves towards the high affinity conformation as it becomes more compact and buries exposed hydrophobic surface after separation of the pilin domain. The mannose binding site was more rigid in the high affinity state, which prevented water penetration into the pocket. The large central β sheet demonstrated a soft spring-like twisting. Its twisting motion was moderately correlated to fluctuations in both the regulatory and the binding region, whereas a weak correlation was seen in a direct comparison of these two distal sites. The results suggest a so called "population shift" model whereby binding of the lectin domain to either the pilin domain or mannose locks the β sheet in a rather twisted or flat conformation, stabilizing the low or the high affinity state, respectively. Proteins 2016; 84:990-1008. © 2016 The Authors. Proteins: Structure, Function, and Bioinformatics Published by Wiley Periodicals, Inc. © 2016 The Authors. Proteins: Structure, Function, and Bioinformatics Published by Wiley Periodicals, Inc.

  13. A Novel Functional Role of Collagen Glycosylation

    PubMed Central

    Jürgensen, Henrik J.; Madsen, Daniel H.; Ingvarsen, Signe; Melander, Maria C.; Gårdsvoll, Henrik; Patthy, Laszlo; Engelholm, Lars H.; Behrendt, Niels

    2011-01-01

    Collagens make up the most abundant component of interstitial extracellular matrices and basement membranes. Collagen remodeling is a crucial process in many normal physiological events and in several pathological conditions. Some collagen subtypes contain specific carbohydrate side chains, the function of which is poorly known. The endocytic collagen receptor urokinase plasminogen activator receptor-associated protein (uPARAP)/Endo180 plays an important role in matrix remodeling through its ability to internalize collagen for lysosomal degradation. uPARAP/Endo180 is a member of the mannose receptor protein family. These proteins all include a fibronectin type II domain and a series of C-type lectin-like domains, of which only a minor part possess carbohydrate recognition activity. At least two of the family members, uPARAP/Endo180 and the mannose receptor, interact with collagens. The molecular basis for this interaction is known to involve the fibronectin type II domain but nothing is known about the function of the lectin domains in this respect. In this study, we have investigated a possible role of the single active lectin domain of uPARAP/Endo180 in the interaction with collagens. By expressing truncated recombinant uPARAP/Endo180 proteins and analyzing their interaction with collagens with high and low levels of glycosylation we demonstrated that this lectin domain interacts directly with glycosylated collagens. This interaction is functionally important because it was found to modulate the endocytic efficiency of the receptor toward highly glycosylated collagens such as basement membrane collagen IV. Surprisingly, this property was not shared by the mannose receptor, which internalized glycosylated collagens independently of its lectin function. This role of modulating its uptake efficiency by a specific receptor is a previously unrecognized function of collagen glycosylation. PMID:21768090

  14. High diversification of CD94 by alternative splicing in New World primates.

    PubMed

    Galindo, John A; Cadavid, Luis F

    2013-04-01

    CD94 forms heterodimers with NKG2A, -C, or -E to constitute lectin-like natural killer cell receptors for MHC-E. Its structure differs from other C-type lectins in that the second α-helix is replaced by a loop that forms the interacting interface with the NKG2 molecules. Although CD94 has remained highly conserved mammals, several alternative splicing variants have been detected in some species. To evaluate the prevalence and significance of this phenomenon, we have cloned and sequenced CD94 cDNAs in six species of New World primates from the Cebidae and Atelidae families. Full-length sequences had a mean similarity of 96 % amongst New World primates and of 90 % to the human orthologue, with little variation in the residues interacting with NKG2 or MHC-E molecules. Despite this high conservation, a total of 14 different splice variants were identified, half of which were shared by two or more primate species. Homology-based modeling of the C-type lectin domain showed that most isoforms folded stably, although they had modifications that prevented its interaction with NKG2 and MHC-E. Two isoforms were predicted to replace the typical CD94 loop by a second α-helix, evidencing a domain fold transition from a CD94 structure to a canonical C-type lectin. These two structures were more similar to members of the CLEC lectin family than to the native CD94. Thus, CD94 has remained conserved in primates to maintain functional interactions with NKG2 and MHC-E, while at the same time has diversified by alternative splicing potentially providing additional functional scenarios.

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

    PubMed

    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.

  16. Determination of the glycosylation-pattern of the middle ear mucosa in guinea pigs.

    PubMed

    Engleder, Elisabeth; Demmerer, Elisabeth; Wang, Xueyan; Honeder, Clemens; Zhu, Chengjing; Studenik, Christian; Wirth, Michael; Arnoldner, Christoph; Gabor, Franz

    2015-04-30

    In the present study the glycosylation pattern of the middle ear mucosa (MEM) of guinea pigs, an approved model for middle ear research, was characterized with the purpose to identify bioadhesive ligands which might prolong the contact time of drug delivery systems with the middle ear mucosa (MEM). To assess the utility of five fluorescein labeled plant lectins with different carbohydrate specificities as bioadhesive ligands, viable MEM specimens were incubated at 4°C and the lectin binding capacities were calculated from the MEM-associated relative fluorescence intensities. Among all lectins under investigation, fluorescein-labeled wheat germ agglutinin (F-WGA) emerged as the highest bioadhesive lectin. In general, the accessibility of carbohydrate moieties of the MEM followed the order: sialic acid and N-acetyl-d-glucosamine (WGA)>mannose and galactosamine (Lensculinaris agglutinin)>N-acetyl-d-glucosamine (Solanumtuberosum agglutinin)>fucose (Ulexeuropaeus isoagglutinin I)>terminal mannose α-(1,3)-mannose (Galanthusnivalis agglutinin). Competitive inhibition studies with the corresponding carbohydrate revealed that F-WGA-binding was inhibited up to 90% confirming specificity of the F-WGA-MEM interaction. The cilia of the MEM were identified as F-WGA binding sites by fluorescence imaging as well as a z-stack of overlays of transmission, F-WGA- and nuclei-stained images of the MEM. Additionally, co-localisation experiments revealed that F-WGA bound to acidic mucopolysaccharides of the MEM. All in all, lectin-mediated bioadhesion to the MEM is proposed as a new concept for drug delivery to prolong the residence time of the drug in the tympanic cavity especially for successful therapy for difficult-to-treat diseases such as otitis media. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

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

    PubMed

    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.

  18. Crystal structure of a dimeric mannose-specific agglutinin from garlic: quaternary association and carbohydrate specificity.

    PubMed

    Chandra, N R; Ramachandraiah, G; Bachhawat, K; Dam, T K; Surolia, A; Vijayan, M

    1999-01-22

    A mannose-specific agglutinin, isolated from garlic bulbs, has been crystallized in the presence of a large excess of alpha-d-mannose, in space group C2 and cell dimensions, a=203.24, b=43.78, c=79.27 A, beta=112.4 degrees, with two dimers in the asymmetric unit. X-ray diffraction data were collected up to a nominal resolution of 2.4 A and the structure was solved by molecular replacement. The structure, refined to an R-factor of 22.6 % and an Rfree of 27.8 % reveals a beta-prism II fold, similar to that in the snowdrop lectin, comprising three antiparallel four-stranded beta-sheets arranged as a 12-stranded beta-barrel, with an approximate internal 3-fold symmetry. This agglutinin is, however, a dimer unlike snowdrop lectin which exists as a tetramer, despite a high degree of sequence similarity between them. A comparison of the two structures reveals a few substitutions in the garlic lectin which stabilise it into a dimer and prevent tetramer formation. Three mannose molecules have been identified on each subunit. In addition, electron density is observed for another possible mannose molecule per dimer resulting in a total of seven mannose molecules in each dimer. Although the mannose binding sites and the overall structure are similar in the subunits of snowdrop and garlic lectin, their specificities to glycoproteins such as GP120 vary considerably. These differences appear, in part, to be a direct consequence of the differences in oligomerisation, implying that variation in quaternary association may be a mode of achieving oligosaccharide specificity in bulb lectins. Copyright 1998 Academic Press.

  19. C-Type Lectin Receptor MCL Facilitates Mincle Expression and Signaling through Complex Formation.

    PubMed

    Miyake, Yasunobu; Masatsugu, Oh-hora; Yamasaki, Sho

    2015-06-01

    C-type lectin receptors expressed in APCs are recently defined pattern recognition receptors that play a crucial role in immune responses against pathogen-associated molecular patterns. Among pathogen-associated molecular patterns, cord factor (trehalose-6,6'-dimycolate [TDM]) is the most potent immunostimulatory component of the mycobacterial cell wall. Two C-type lectin receptors, macrophage-inducible C-type lectin (Mincle) and macrophage C-type lectin (MCL), are required for immune responses against TDM. Previous studies indicate that MCL is required for TDM-induced Mincle expression. However, the mechanism by which MCL induces Mincle expression has not been fully understood. In this study, we demonstrate that MCL interacts with Mincle to promote its surface expression. After LPS or zymosan stimulation, MCL-deficient bone marrow-derived dendritic cells (BMDCs) had a lower level of Mincle protein expression, although mRNA expression was comparable with wild-type BMDCs. Meanwhile, BMDCs from MCL transgenic mice showed an enhanced level of Mincle expression on the cell surface. MCL was associated with Mincle through the stalk region and this region was necessary and sufficient for the enhancement of Mincle expression. This interaction appeared to be mediated by the hydrophobic repeat of MCL, as substitution of four hydrophobic residues within the stalk region with serine (MCL(4S)) abolished the function to enhance the surface expression of Mincle. MCL(4S) mutant failed to restore the defective TDM responses in MCL-deficient BMDCs. These results suggest that MCL positively regulates Mincle expression through protein-protein interaction via its stalk region, thereby magnifying Mincle-mediated signaling. Copyright © 2015 by The American Association of Immunologists, Inc.

  20. Evidence for the Adhesive Function of the Exopolysaccharide of Hyphomonas Strain MHS-3 in Its Attachment to Surfaces

    PubMed Central

    Quintero, E. J.; Weiner, R. M.

    1995-01-01

    Hyphomonas strain MHS-3 (MHS-3) is a marine procaryote with a biphasic life cycle and which has prosthecate stages that adhere to submerged substrata. We found that adherent forms produced an exopolysaccharide (EPS) capsule that bound Glycine max lectin, Arachis hypogaea lectin, and Bauhinia purpurea lectin (BPA), each having affinity for N-acetyl-d-galactosamine. It also bound the dye Calcofluor. BPA and Calcofluor were tested for the ability to hinder MHS-3 adhesion to glass surfaces; they reduced attachment by >50 and >85%, respectively. Periodate treatment also reduced attachment (by >80%), but pronase treatment did not. Furthermore, an EPS(sup-) variant, Hyphomonas strain MHS-3 rad, did not attach well to surfaces. These results suggest that the MHS-3 EPS capsule is an adhesin. PMID:16535028

  1. Extracorporeal virus elimination for the treatment of severe Ebola virus disease--first experience with lectin affinity plasmapheresis.

    PubMed

    Büttner, Stefan; Koch, Benjamin; Dolnik, Olga; Eickmann, Markus; Freiwald, Tilo; Rudolf, Sarah; Engel, Jürgen; Becker, Stephan; Ronco, Claudio; Geiger, Helmut

    2014-01-01

    Therapeutic options for Ebola virus disease (EVD) are currently limited to (1) best supportive care, and (2) evolving virus-specific therapies, resulting from decades of analyzing one of the world's deadliest diseases. Supportive care ranges from oral or intravenous rehydration therapy and anti-emetics in developing countries to much more extensive life-support interventions in resource-rich countries. Current EVD-specific therapies attempt to either interfere with the earliest steps of viral replication or to elicit a strong immune response against the virus. An entirely new approach is the extracorporeal elimination of viruses and viral glycoproteins by lectin affinity plasmapheresis. Herein, we report for the first time the successful and safe use of lectin affinity plasmapheresis in a patient with severe Ebola virus disease. © 2015 S. Karger AG, Basel.

  2. Inhibition of Pseudomonas aeruginosa adhesion to fibronectin by PA-IL and monosaccharides: involvement of a lectin-like process.

    PubMed

    Rebiere-Huët, Julie; Di Martino, Patrick; Hulen, Christian

    2004-05-01

    Pseudomonas aeruginosa adherence to fibronectin has been shown to be important to bacterial colonization and infection. To better understand the mechanisms involved in this interaction, the role of the carbohydrate moiety of the fibronectin molecule in P. aeruginosa adhesion was studied. Strain NK 125 502 adhered to immobilized fibronectin with an adherence index of 4.8 x 10(5) CFU/ micro g. Periodic oxidation of fibronectin markedly reduced the adhesion of P. aeruginosa, while a neuraminidase treatment increased bacteria adhesion. N-Acetylgalactosamine, N-acetylglucosamine, sialic acid, and also lectin PA-IL worked as efficient inhibitors in adhesion assays: 59%, 70.7%, 100%, and 60% of inhibition, respectively. We have demonstrated here the involvement of a lectin-like process in the interaction of P. aeruginosa NK 125 502 with immobilized fibronectin.

  3. How to Crack the Sugar Code.

    PubMed

    Gabius, H-J

    2017-01-01

    The known ubiquitous presence of glycans fulfils an essential prerequisite for fundamental roles in cell sociology. Since carbohydrates are chemically predestined to form biochemical messages of a maximum of structural diversity in a minimum of space, coding of biological information by sugars is the reason for the broad occurrence of cellular glycoconjugates. Their glycans originate from sophisticated enzymatic assembly and dynamically adaptable remodelling. These signals are read and translated into effects by receptors (lectins). The functional pairing between lectins and their counterreceptor(s) is highly specific, often orchestrated by intimate co-regulation of the receptor, the cognate glycan and the bioactive scaffold (e.g., an integrin). Bottom-up approaches, teaming up synthetic and supramolecular chemistry to prepare fully programmable nanoparticles as binding partners with systematic network analysis of lectins and rational design of variants, enable us to delineate the rules of the sugar code.

  4. Rhizoid differentiation of Spirogyra is regulated by substratum.

    PubMed

    Ikegaya, Hisato; Sonobe, Seiji; Murakami, Kohei; Shimmen, Teruo

    2008-11-01

    Some species of Spirogyra can anchor to substratum with rod- or rosette-shaped rhizoid (hapteron). The rhizoid differentiation can be induced by cutting algal filaments in a laboratory. Requirement of contact stimulation for rhizoid differentiation has been reported (Nagata in Plant Cell Physiol 14:531-541, 1973a). However, the control mechanism of rhizoid morphology has not been elucidated. When cut filaments were incubated on the glass surface, start of tip growth, secretion of lectin-binding material and callose synthesis were observed. In the absence of contact to the glass surface, none of above phenomena was induced. Systematic analysis showed that rosette-shaped rhizoid was formed only on the hydrophobic substratum. On the hydrophobic substratum, both Bandeiraea (Griffonia) simplicifolia lectin and jacalin strongly stained the rhizoids. On the hydrophilic substratum, however, only Bandeiraea (Griffonia) simplicifolia lectin strongly stained the rhizoids.

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

    Wurzburg, Beth A.; Tarchevskaya, Svetlana S.; Jardetzky, Theodore S.

    CD23, the low-affinity receptor for IgE (Fc{var_epsilon}RII), regulates IgE synthesis and also mediates IgE-dependent antigen transport and processing. CD23 is a unique Fc receptor belonging to the C-type lectin-like domain superfamily and binds IgE in an unusual, non-lectin-like manner, requiring calcium but not carbohydrate. We have solved the high-resolution crystal structures of the human CD23 lectin domain in the presence and absence of Ca{sup 2+}. The crystal structures differ significantly from a previously determined NMR structure and show that calcium binding occurs at the principal binding site, but not at an auxiliary site that appears to be absent in humanmore » CD23. Conformational differences between the apo and Ca{sup 2+} bound structures suggest how IgE-Fc binding can be both calcium-dependent and carbohydrate-independent.« less

  6. Mannose-binding lectin binds to a range of clinically relevant microorganisms and promotes complement deposition.

    PubMed

    Neth, O; Jack, D L; Dodds, A W; Holzel, H; Klein, N J; Turner, M W

    2000-02-01

    Mannose-binding lectin (MBL) is a collagenous serum lectin believed to be of importance in innate immunity. Genetically determined low levels of the protein are known to predispose to infections. In this study the binding of purified MBL to pathogens isolated from immunocompromised children was investigated by flow cytometry. Diverse Candida species, Aspergillus fumigatus, Staphylococcus aureus, and beta-hemolytic group A streptococci exhibited strong binding of MBL, whereas Escherichia coli, Klebsiella species, and Haemophilus influenzae type b were characterized by heterogeneous binding patterns. In contrast, beta-hemolytic group B streptococci, Streptococcus pneumoniae, and Staphylococcus epidermidis showed low levels of binding. Bound MBL was able to promote C4 deposition in a concentration-dependent manner. We conclude that MBL may be of importance in first-line immune defense against several important pathogens.

  7. The glycoconjugate sugar residues of the sessile and motile cells in the thymus of normal and cyclosporin-A-treated rats: lectin histochemistry.

    PubMed

    Gheri, G; Gheri Bryk, S; Riccardi, R; Sgambati, E; Cirri Borghi, M B

    2002-01-01

    It is well known that cell surface glycoconjugates play a determinant role in cellular recognition, cell-to-cell adhesion and serve as receptor molecules. T-lymphocytes are in strict contact with the thymic epithelial cells, which control their process of maturation and proliferation. On the other hand the normal maturation of the epithelial cells is believed to be induced by T-lymphocytes. For these reasons we have studied the glycoconjugates saccharidic moieties of the sessile and motile cells in the thymus of normal male albino Wistar rats and their changes following cyclosporin-A treatment, using a battery of seven HRP-lectins. Cytochemical controls were performed for specificity of lectin-sugar reaction. Some sections were pre-treated with neuraminidase prior to staining with HRP-lectins. Our results have demonstrated, in the control rats, a large amount and a variety of terminal and subterminal oligosaccharides within and/or on the epithelial thymic cells and in macrophages. After cyclosporin-A treatment, among the thymic epithelial cells, the subcapsular, paraseptal and perivascular cells showed the loss of some sugar residues, which characterized the same cells in the intact thymus. Some hypotheses are reported on the role played by the glycoconjugate sugar residues in control and cyclosporin-A treated rats.

  8. Glycoconjugate sugar residues in the chick embryo developing lung: a lectin histochemical study.

    PubMed

    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.

  9. Beta-propeller crystal structure of Psathyrella velutina lectin: an integrin-like fungal protein interacting with monosaccharides and calcium.

    PubMed

    Cioci, Gianluca; Mitchell, Edward P; Chazalet, Valerie; Debray, Henri; Oscarson, Stefan; Lahmann, Martina; Gautier, Catherine; Breton, Christelle; Perez, Serge; Imberty, Anne

    2006-04-14

    The lectin from the mushroom Psathyrella velutina recognises specifically N-acetylglucosamine and N-acetylneuraminic acid containing glycans. The crystal structure of the 401 amino acid residue lectin shows that it adopts a very regular seven-bladed beta-propeller fold with the N-terminal region tucked into the central cavity around the pseudo 7-fold axis. In the complex with N-acetylglucosamine, six monosaccharides are bound in pockets located between two consecutive propeller blades. Due to the repeats shown by the sequence the binding sites are very similar. Five hydrogen bonds between the protein and the sugar hydroxyl and N-acetyl groups stabilize the complex, together with the hydrophobic interactions with a conserved tyrosine and histidine. The complex with N-acetylneuraminic acid shows molecular mimicry with the same hydrogen bond network, but with different orientations of the carbohydrate ring in the binding site. The beta-hairpin loops connecting the two inner beta-strands of each blade are metal binding sites and two to three calcium ions were located in the structure. The multispecificity and high multivalency of this mushroom lectin, combined with its similarity to the extracellular domain of an important class of cell adhesion molecules, integrins, are another example of the outstanding success of beta-propeller structures as molecular binding machines in nature.

  10. Forces in yeast flocculation

    NASA Astrophysics Data System (ADS)

    El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Vincent, Stéphane P.; Abellán Flos, Marta; Hols, Pascal; Lipke, Peter N.; Dufrêne, Yves F.

    2015-01-01

    In the baker's yeast Saccharomyces cerevisiae, cell-cell adhesion (``flocculation'') is conferred by a family of lectin-like proteins known as the flocculin (Flo) proteins. Knowledge of the adhesive and mechanical properties of flocculins is important for understanding the mechanisms of yeast adhesion, and may help controlling yeast behaviour in biotechnology. We use single-molecule and single-cell atomic force microscopy (AFM) to explore the nanoscale forces engaged in yeast flocculation, focusing on the role of Flo1 as a prototype of flocculins. Using AFM tips labelled with mannose, we detect single flocculins on Flo1-expressing cells, showing they are widely exposed on the cell surface. When subjected to force, individual Flo1 proteins display two distinct force responses, i.e. weak lectin binding forces and strong unfolding forces reflecting the force-induced extension of hydrophobic tandem repeats. We demonstrate that cell-cell adhesion bonds also involve multiple weak lectin interactions together with strong unfolding forces, both associated with Flo1 molecules. Single-molecule and single-cell data correlate with microscale cell adhesion behaviour, suggesting strongly that Flo1 mechanics is critical for yeast flocculation. These results favour a model in which not only weak lectin-sugar interactions are involved in yeast flocculation but also strong hydrophobic interactions resulting from protein unfolding.

  11. Influence of Trp flipping on carbohydrate binding in lectins. An example on Aleuria aurantia lectin AAL.

    PubMed

    Houser, Josef; Kozmon, Stanislav; Mishra, Deepti; Mishra, Sushil K; Romano, Patrick R; Wimmerová, Michaela; Koča, Jaroslav

    2017-01-01

    Protein-carbohydrate interactions are very often mediated by the stacking CH-π interactions involving the side chains of aromatic amino acids such as tryptophan (Trp), tyrosine (Tyr) or phenylalanine (Phe). Especially suitable for stacking is the Trp residue. Analysis of the PDB database shows Trp stacking for 265 carbohydrate or carbohydrate like ligands in 5 208 Trp containing motives. An appropriate model system to study such an interaction is the AAL lectin family where the stacking interactions play a crucial role and are thought to be a driving force for carbohydrate binding. In this study we present data showing a novel finding in the stacking interaction of the AAL Trp side chain with the carbohydrate. High resolution X-ray structure of the AAL lectin from Aleuria aurantia with α-methyl-l-fucoside ligand shows two possible Trp side chain conformations with the same occupation in electron density. The in silico data shows that the conformation of the Trp side chain does not influence the interaction energy despite the fact that each conformation creates interactions with different carbohydrate CH groups. Moreover, the PDB data search shows that the conformations are almost equally distributed across all Trp-carbohydrate complexes, which would suggest no substantial preference for one conformation over another.

  12. 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.

    PubMed

    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.

  13. Glycoconjugate distribution in early human notochord and axial mesenchyme.

    PubMed

    Götz, W; Quondamatteo, F

    2001-02-01

    Glycosylation patterns of cells and tissues give insights into spatially and temporally regulated developmental processes and can be detected histochemically using plant lectins with specific affinities for sugar moieties. The early development of the vertebral column in man is a process which has never been investigated by lectin histochemistry. Therefore, we studied binding of several lectins (AIA, Con A, GSA II, LFA, LTA, PNA, RCA I, SBA, SNA, WGA) in formaldehyde-fixed sections of the axial mesenchyme of 5 human embryos in Carnegie stages 12-15. During these developmental stages, an unsegmented mesenchyme covers the notochord. Staining patterns did not show striking temporal variations except for SBA which stained the cranial axial mesenchyme only in the early stage 12 embryo and for PNA, of which the staining intensity in the mesenchyme decreased with age. The notochord appeared as a highly glycosylated tissue. Carbohydrates detected may correspond to adhesion molecules or to secreted substances like proteoglycans or proteins which could play an inductive role, for example, for the neural tube. The axial perinotochordal unsegmented mesenchyme showed strong PNA binding. Therefore, its function as a PNA-positive "barrier" tissue is discussed. The endoderm of the primitive gut showed a lectin-binding pattern that was similar to that of the notochord, which may correlate with interactions between these tissues during earlier developmental stages.

  14. Histochemistry of lectin-binding sites in Halicryptus spinulosus (Priapulida).

    PubMed

    Busch, A; Schumacher, U; Storch, V

    2001-02-01

    Priapulida represent one of the phylogenetically oldest multicellular animal groups. In multicellular animals (Metazoa) cell-to-cell and cell-to-matrix interactions are often mediated by carbohydrate residues of glycoconjugates. To analyze the carbohydrate composition of a phylogenetically old species, lectin histochemistry was employed on 5 specimens of the priapulid Halicryptus spinulosus. Many lectins bound to the chitin-containing cuticle, including those specific for carbohydrates other than N-acetylglucosamine, the principle building block of chitin. The connective tissue of the animals contained both N-acetylglucosamine and N-acetylgalactosamine. Mannose residues were widely distributed with the exception of the cuticle, but complex type carbohydrates were not present in the entire animal. Sialic acid residues were only detected in the cuticle and brush border of the intestinal epithelium, while fucose was limited to the cuticle. Thus, the lectin-binding pattern indicated that sugars typical for the linking region of both N- and O-glycoproteins in mammals are also present in H. spinulosus. Carbohydrate residues that are typical for the complex type of N-linked glycans in vertebrates are not present as are carbohydrate residues typical for the termination of O-linked carbohydrate chains. Hence, a truncated form of both N- and O-linked glycosylation is present in H. spinulosus indicating that more complex patterns of glycosylation developed later during evolution.

  15. Cell cycle-dependent O-GlcNAc modification of tobacco histones and their interaction with the tobacco lectin.

    PubMed

    Delporte, Annelies; De Zaeytijd, Jeroen; De Storme, Nico; Azmi, Abdelkrim; Geelen, Danny; Smagghe, Guy; Guisez, Yves; Van Damme, Els J M

    2014-10-01

    The Nicotiana tabacum agglutinin or Nictaba is a nucleocytoplasmic lectin that is expressed in tobacco after the plants have been exposed to jasmonate treatment or insect herbivory. Nictaba specifically recognizes GlcNAc residues. Recently, it was shown that Nictaba is interacting in vitro with the core histone proteins from calf thymus. Assuming that plant histones - similar to their animal counterparts - undergo O-GlcNAcylation, this interaction presumably occurs through binding of the lectin to the O-GlcNAc modification present on the histones. Hereupon, the question was raised whether this modification also occurs in plants and if it is cell cycle dependent. To this end, histones were purified from tobacco BY-2 suspension cells and the presence of O-GlcNAc modifications was checked. Concomitantly, O-GlcNAcylation of histone proteins was studied. Our data show that similar to animal histones plant histones are modified by O-GlcNAc in a cell cycle-dependent fashion. In addition, the interaction between Nictaba and tobacco histones was confirmed using lectin chromatography and far Western blot analysis. Collectively these findings suggest that Nictaba can act as a modulator of gene transcription through its interaction with core histones. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  16. Molecular cloning and characterization of a C-type lectin in yellow catfish Tachysurus fulvidraco.

    PubMed

    Ke, F; Zhang, H B; Wang, Y; Hou, L F; Dong, H J; Wang, Z F; Pan, G W; Cao, X Y

    2016-09-01

    This study represents the first report of a C-type lectin (ctl) in yellow catfish Tachysurus fulvidraco. The complete sequence of ctl complementary (c)DNA consisted of 685 nucleotides. The open reading frame potentially encoded a protein of 177 amino acids with a calculated molecular mass of c.y 20.204 kDa. The deduced amino-acid sequence contained a signal peptide and a single carbohydrate recognition domain with four cysteine residues and GlnProAsp (QPD) and TrpAsnAsp (WND) motifs. Ctl showed the highest identity (56.0%) to the predicted lactose binding lectin from channel catfish Ictalurus punctatus. Quantitative real-time (qrt)-PCR analysis showed that ctl messenger (m)RNA was constitutively expressed in all examined tissues in normal fish, with high expression in trunk kidney and head kidney, which was increased following Aeromonas hydrophila challenge in a duration-dependent manner. Purified recombinant Ctl (rCtl) from Escherichia coli BL21 was able to bind and agglutinate Gram-positive and Gram-negative bacteria in a calcium-dependent manner. These results suggested that Ctl might be a C-type lectin of T. fulvidraco involved in innate immune responses as receptors (PRR). © 2016 The Fisheries Society of the British Isles.

  17. Protein Adsorption and Its Role in Bacterial Film Development

    DTIC Science & Technology

    1989-06-27

    only the secondary antibody conjugated to alkaline phosphatase was used. Combined Amino Acids as Measured by HPLC We are interested in a simple, direct...specific assay for chitin that relies on the lectin, wheat germ agglutinin (WGA). Lectins are a general class of proteins that bind to carbohydrates. The...protein; 2) a new method for measuring combined amino acids (includes proteins) in seawater was shown to measure higher concentration than the old

  18. O-Alkylated heavy atom carbohydrate probes for protein X-ray crystallography: Studies towards the synthesis of methyl 2-O-methyl-L-selenofucopyranoside.

    PubMed

    Sommer, Roman; Hauck, Dirk; Varrot, Annabelle; Imberty, Anne; Künzler, Markus; Titz, Alexander

    2016-01-01

    Selenoglycosides are used as reactive glycosyl donors in the syntheses of oligosaccharides. In addition, such heavy atom analogs of natural glycosides are useful tools for structure determination of their lectin receptors using X-ray crystallography. Some lectins, e.g., members of the tectonin family, only bind to carbohydrate epitopes with O-alkylated ring hydroxy groups. In this context, we report the first synthesis of an O -methylated selenoglycoside, specifically methyl 2- O -methyl-L-selenofucopyranoside, a ligand of the lectin tectonin-2 from the mushroom Laccaria bicolor . The synthetic route required a strategic revision and further optimization due to the intrinsic lability of alkyl selenoglycosides, in particular for the labile fucose. Here, we describe a successful synthetic access to methyl 2- O -methyl-L-selenofucopyranoside in 9 linear steps and 26% overall yield starting from allyl L-fucopyranoside.

  19. Increased lectin binding capacity of trophoblastic cells of late day 5 rat blastocysts.

    PubMed Central

    Stein, B A; Shaw, T J; Turner, V F; Murphy, C R

    1994-01-01

    The binding of lectins to the trophoblast of rat blastocysts has been studied using quantitative ultrastructural cytochemistry. Rat blastocysts from early, mid and late d 5 of gestation were stained using biotinylated lectins (Phytolacca americana [Phy am], fucose binding protein [FBP] and soybean agglutinin [SBA]) and a sensitive avidin-ferritin cytochemical method. Electron micrographs of ferritin particles along the membrane were processed to produce images for which grey scale levels could be established and the ferritin particles automatically counted. The ferritin:membrane ratio was then calculated. Increased binding with Phy am (which detects short chain oligosaccharides) was found after midday of d 5, i.e. after hatching. Binding of FBP and SBA did not alter during the period studied. The increased concentration of oligosaccharides on the blastocyst surface membrane after hatching may have important implications for blastocyst attachment to the endometrium. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:7649802

  20. Differential Lectin Agglutination of Fetal, Dividing-Postnatal, and Malignant Hepatocytes

    PubMed Central

    Becker, F. F.

    1974-01-01

    Numerous studies have reported the capacity of the lectin, concanavalin A, to agglutinate selected cell-types. The finding that cells transformed in culture, embryonic cells, and malignant cells are all agglutinated by this substance, may contribute to our understanding of the oncogenic process. The present study compared the response to concanavalin A of rat hepatocytes derived from livers of differing developmental and mitotic-status as well as those derived from malignant liver tumors (hepatomas). Fetal hepatocytes and hepatoma cells were highly susceptible to agglutination while hepatocytes from post-natal livers, whether dividing or quiescent, were not. Treatment with protease(s) did not make the interphase hepatocyte agglutinable. These data emphasize the importance of examining a wide variety of cells in attempting to understand the interaction of lectins on cell surfaces, and further, demonstrate the value of obtaining cells directly from tissue(s) during differing physiologic and pathologic states. Images PMID:4373708

  1. Screening of Caatinga plants as sources of lectins and trypsin inhibitors.

    PubMed

    Arcoverde, José Hélton Vasconcelos; Carvalho, Aline de Souza; Neves, Fernanda Pacífico de Almeida; Dionízio, Bianca Paiva; Pontual, Emmanuel Viana; Paiva, Patrícia Maria Guedes; Napoleão, Thiago Henrique; Correia, Maria Tereza dos Santos; da Silva, Márcia Vanusa; Carneiro-da-Cunha, Maria das Graças

    2014-01-01

    Although it is one of the most threatened areas in the Earth, there are few studies on the biotechnological potential of the Caatinga. This work evaluated 36 extracts from 27 Caatinga plants for lectin and trypsin inhibitor activities. The presence of lectin was detected in 77.7% of samples by haemagglutinating assay. The highest values of specific haemagglutinating activity were found in extracts of leaves from Mimosa lewesii, Bauhinia acuruana and Manilkara rufula and in branches from Myracrodruon urundeuva. Trypsin inhibitor activity was detected in 63.9% of the tested extracts, strong inhibitory effect (>70%) being found in 11 samples. This work demonstrates that Caatinga is a potential source of bioactive plant proteins that can be isolated and studied for several applications. The biochemical prospecting of Caatinga is essential for collection of bioactive principles so as to add conservation value to the region.

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

    PubMed

    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.

  3. Extensive Basal Level Activation of Complement Mannose-Binding Lectin-Associated Serine Protease-3: Kinetic Modeling of Lectin Pathway Activation Provides Possible Mechanism.

    PubMed

    Oroszlán, Gábor; Dani, Ráhel; Szilágyi, András; Závodszky, Péter; Thiel, Steffen; Gál, Péter; Dobó, József

    2017-01-01

    Serine proteases (SPs) are typically synthesized as precursors, termed proenzymes or zymogens, and the fully active form is produced via limited proteolysis by another protease or by autoactivation. The lectin pathway of the complement system is initiated by mannose-binding lectin (MBL)-associated SPs (MASP)-1, and MASP-2, which are known to be present as proenzymes in blood. The third SP of the lectin pathway, MASP-3, was recently shown to be the major activator, and the exclusive "resting blood" activator of profactor D, producing factor D, the initiator protease of the alternative pathway. Because only activated MASP-3 is capable of carrying out this cleavage, it was presumed that a significant fraction of MASP-3 must be present in the active form in resting blood. Here, we aimed to detect active MASP-3 in the blood by a more direct technique and to quantitate the active to zymogen ratio. First, MASPs were partially purified (enriched) from human plasma samples by affinity chromatography using immobilized MBL in the presence of inhibitors. Using this MASP pool, only the zymogen form of MASP-1 was detected by Western blot, whereas over 70% MASP-3 was in an activated form in the same samples. Furthermore, the active to zymogen ratio of MASP-3 showed little individual variation. It is enigmatic how MASP-3, which is not able to autoactivate, is present mostly as an active enzyme, whereas MASP-1, which has a potent autoactivation capability, is predominantly proenzymic in resting blood. In an attempt to explain this phenomenon, we modeled the basal level fluid-phase activation of lectin pathway proteases and their subsequent inactivation by C1 inhibitor and antithrombin using available and newly determined kinetic constants. The model can explain extensive MASP-3 activation only if we assume efficient intracomplex activation of MASP-3 by zymogen MASP-1. On the other hand, the model is in good agreement with the fact that MASP-1 and -2 are predominantly proenzymic and some of them is present in the form of inactive serpin-protease complexes. As an alternative hypothesis, MASP-3 activation by proprotein convertases is also discussed.

  4. Radiolabeled Peptide Scaffolds for PET/SPECT - Optical in Vivo Imaging of Carbohydrate-Lectin Interactions

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

    Deutscher, Susan

    2014-09-30

    The objective of this research is to develop phage display-selected peptides into radio- and fluoresecently- labeled scaffolds for the multimodal imaging of carbohydrate-lectin interactions. While numerous protein and receptor systems are being explored for the development of targeted imaging agents, the targeting and analysis of carbohydrate-lectin complexes in vivo remains relatively unexplored. Antibodies, nanoparticles, and peptides are being developed that target carbohydrate-lectin complexes in living systems. However, antibodies and nanoparticles often suffer from slow clearance and toxicity problems. Peptides are attractive alternative vehicles for the specific delivery of radionuclides or fluorophores to sites of interest in vivo, although, because ofmore » their size, uptake and retention may be less than antibodies. We have selected high affinity peptides that bind a specific carbohydrate-lectin complex involved in cell-cell adhesion and cross-linking using bacteriophage (phage) display technologies (1,2). These peptides have allowed us to probe the role of these antigens in cell adhesion. Fluorescent versions of the peptides have been developed for optical imaging and radiolabeled versions have been used in single photon emission computed tomography (SPECT) and positron emission tomography (PET) in vivo imaging (3-6). A benefit in employing the radiolabeled peptides in SPECT and PET is that these imaging modalities are widely used in living systems and offer deep tissue sensitivity. Radiolabeled peptides, however, often exhibit poor stability and high kidney uptake in vivo. Conversely, optical imaging is sensitive and offers good spatial resolution, but is not useful for deep tissue penetration and is semi-quantitative. Thus, multimodality imaging that relies on the strengths of both radio- and optical- imaging is a current focus for development of new in vivo imaging agents. We propose a novel means to improve the efficacy of radiolabeled and fluorescently labeled peptides, including our lectin/carbohydrate- targeting peptides, by displaying the targeting epitopes on small ~29 amino acid cyclic plant protein scaffolds known as cyclotides. Cyclotides are extremely stable molecules with long serum half-lives and low kidney uptake (7). More than one copy of the peptide can be engineered into the cyclotide loops, thus increasing the avidity of the peptide construct for its target.« less

  5. Pathogenic and Nonpathogenic Strains of Entamoeba histolytica can be Differentiated by Monoclonal Antibodies to the Galactose-Specific Adherence Lectin

    DTIC Science & Technology

    1991-04-01

    AD- A235 913 DEVELOPMENT Ei ENGINEERING CENTER CRDEC-TR-268 PATHOGENIC AND NONPATHOGENIC STRAINS OF ENTAMOEBA HISTOLYTICA CAN BE DIFFERENTIATED BY...Pathogenic and Nonpathogenic Strains of Entamoeba Histolytica can be Differentiated by Monoclonal PR-IFJlX2XXRPEW Antibodies to the Galactose-Specific...galactose lectin produced by Entamoeba histolytica provide the basis for development of a model system for the environmental detection of adherence and

  6. Surface reaction of Leishmania. III. Ulex europaeus II lectin affinity for excreted factor (EF) serotype A strains.

    PubMed

    Greenblatt, C L; Meline, D; Slutzky, G M; Schnur, L F; Levene, C

    1984-04-01

    Eukaryotic parasites, including species of Leishmania, acquire or synthesize carbohydrate moieties similar to human blood group antigens. Leishmanial strains separate into three serotypes: A, B and AB. All strains containing the A component are agglutinated by Ulex europaeus lectin. Inhibition by haptene sugar suggests that a Ulex II-like receptor is involved. Organic solvents, but not protease treatment, remove its reactivity, suggesting that the receptor is a glycolipid.

  7. Two antibacterial C-type lectins from crustacean, Eriocheir sinensis, stimulated cellular encapsulation in vitro.

    PubMed

    Jin, Xing-Kun; Li, Shuang; Guo, Xiao-Nv; Cheng, Lin; Wu, Min-Hao; Tan, Shang-Jian; Zhu, You-Ting; Yu, Ai-Qing; Li, Wei-Wei; Wang, Qun

    2013-12-01

    The first step of host fighting against pathogens is that pattern recognition receptors recognized pathogen-associated molecular patterns. However, the specificity of recognition within the innate immune molecular of invertebrates remains largely unknown. In the present study, we investigated how invertebrate pattern recognition receptor (PRR) C-type lectins might be involved in the antimicrobial response in crustacean. Based on our previously obtained completed coding regions of EsLecA and EsLecG in Eriocheir sinensis, the recombinant EsLectin proteins were produced via prokaryotic expression system and affinity chromatography. Subsequently, both rEsLecA and rEsLecG were discovered to have wide spectrum binding activities towards microorganisms, and their microbial-binding was calcium-independent. Moreover, the binding activities of both rEsLecA and rEsLecG induced the aggregation against microbial pathogens. Both microorganism growth inhibitory activities assays and antibacterial activities assays revealed their capabilities of suppressing microorganisms growth and directly killing microorganisms respectively. Furthermore, the encapsulation assays signified that both rEsLecA and rEsLecG could stimulate the cellular encapsulation in vitro. Collectively, data presented here demonstrated the successful expression and purification of two C-type lectins proteins in the Chinese mitten crab, and their critical role in the innate immune system of an invertebrate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Computer simulation of protein—carbohydrate complexes: application to arabinose-binding protein and pea lectin

    NASA Astrophysics Data System (ADS)

    Rao, V. S. R.; Biswas, Margaret; Mukhopadhyay, Chaitali; Balaji, P. V.

    1989-03-01

    The CCEM method (Contact Criteria and Energy Minimisation) has been developed and applied to study protein-carbohydrate interactions. The method uses available X-ray data even on the native protein at low resolution (above 2.4 Å) to generate realistic models of a variety of proteins with various ligands. The two examples discussed in this paper are arabinose-binding protein (ABP) and pea lectin. The X-ray crystal structure data reported on ABP-β- L-arabinose complex at 2.8, 2.4 and 1.7 Å resolution differ drastically in predicting the nature of the interactions between the protein and ligand. It is shown that, using the data at 2.4 Å resolution, the CCEM method generates complexes which are as good as the higher (1.7 Å) resolution data. The CCEM method predicts some of the important hydrogen bonds between the ligand and the protein which are missing in the interpretation of the X-ray data at 2.4 Å resolution. The theoretically predicted hydrogen bonds are in good agreement with those reported at 1.7 Å resolution. Pea lectin has been solved only in the native form at 3 Å resolution. Application of the CCEM method also enables us to generate complexes of pea lectin with methyl-α- D-glucopyranoside and methyl-2,3-dimethyl-α- D-glucopyranoside which explain well the available experimental data in solution.

  9. Screening method of carbohydrate-binding proteins in biological sources by capillary affinity electrophoresis and its application to determination of Tulipa gesneriana agglutinin in tulip bulbs.

    PubMed

    Nakajima, Kazuki; Kinoshita, Mitsuhiro; Oda, Yasuo; Masuko, Takashi; Kaku, Hanae; Shibuya, Naoto; Kakehi, Kazuaki

    2004-09-01

    We developed capillary affinity electrophoresis (CAE) to analyze the molecular interaction between carbohydrate chains and proteins in solution state. A mixture of oligosaccharides derived from a glycoprotein was labeled with 8-aminopyrene-1,3,6-trisulfonate (APTS), and used as glycan library without isolation. Interaction of a carbohydrate-binding protein with each oligosaccharide in the mixture could be simultaneously observed, and relative affinities of oligosaccharides toward the protein were accurately determined. In this study, we applied CAE to detect the presence of lectins in some plants (Japanese elderberry bark and tulip bulb). In the crude extract of the elderberry bark, binding activity toward sialo-carbohydrate chains could be easily detected. We also examined the presence of lectins in the crude extract of tulip bulbs and determined the detailed carbohydrate-binding specificity of Tulipa gesneriana agglutinin (TGA), one of the lectins from tulip bulbs. Kinetic studies demonstrated that TGA showed novel carbohydrate-binding specificity and preferentially recognized triantennary oligosaccharides with Gal residues at nonreducing termini and a Fuc residue linked through alpha(1-6) linkage at chitobiose portion of the reducing termini but not tetraantennary carbohydrates. The results described here indicate that CAE will be a valuable method for both screening of lectins in natural sources and determination of their detailed carbohydrate-binding specificities.

  10. Light microscopic detection of sugar residues in glycoconjugates of salivary glands and the pancreas with lectin-horseradish peroxidase conjugates. I. Mouse.

    PubMed

    Schulte, B A; Spicer, S S

    1983-12-01

    Mouse salivary glands and pancreases were stained with a battery of ten horseradish peroxidase-conjugated lectins. Lectin staining revealed striking differences in the structure of oligosaccharides of stored intracellular secretory glycoproteins and glycoconjugates associated with the surface of epithelial cells lining excretory ducts. The percentage of acinar cells containing terminal alpha-N-acetylgalactosamine residues varied greatly in submandibular glands of 30 male mice, but all submandibular acinar cells contained oligosaccharides with terminal sialic acid and penultimate beta-galactose residues. The last named dimer was abundant in secretory glycoprotein of all mucous acinar cells in murine sublingual glands and an additional 20-50% of these cells in all glands contained terminal N-acetylglucosamine residues. In contrast, terminal alpha-N-acetylgalactosamine was abundant in sublingual serous demilune secretions. Serous acinar cells in the exorbital lacrimal gland, posterior lingual gland, parotid gland and pancreas exhibited a staining pattern unique to each organ. In contrast, the apical cytoplasm and surface of striated duct epithelial cells in the submandibular, sublingual, parotid and exorbital lacrimal gland stained similarly. A comparison of staining with conjugated lectins reported biochemically to have very similar carbohydrate binding specificity has revealed some remarkable differences in their reactivity, suggesting different binding specificity for the same terminal sugars having different glycosidic linkages or with different penultimate sugar residues.

  11. Multi-specificity of a Psathyrella velutina mushroom lectin: heparin/pectin binding occurs at a site different from the N-acetylglucosamine/N-acetylneuraminic acid-specific site.

    PubMed

    Ueda, H; Saitoh, T; Kojima, K; Ogawa, H

    1999-09-01

    An N-acetylglucosamine (GlcNAc)/N-acetylneuraminic acid-specific lectin from the fruiting body of Psathyrella velutina (PVL) is a useful probe for the detection and fractionation of specific carbohydrates. In this study, PVL was found to exhibit multispecificity to acidic polysaccharides and sulfatides. Purified PVL and a counterpart lectin to PVL in the mycelium interact with heparin neoproteoglycans, as detected by both membrane analysis and solid phase assay. The pH-dependencies of the binding to heparin and GlcNAc5-6 differ. The heparin binding of PVL is inhibited best by pectin, polygalacturonic acid, and highly sulfated polysaccharides, but not by GlcNAc, colominic acid, or other glycosaminoglycans. Sandwich affinity chromatography indicated that PVL can simultaneously interact with heparin- and GlcNAc-containing macromolecules. Extensive biotinylation was found to suppress the binding activity to heparin while the GlcNAc binding activity is retained. On the other hand, biotinyl PVL binds to sulfatide and the binding is not inhibited by GlcNAc, N-acetylneuraminic acid, or heparin. These results indicate that PVL is a multi-ligand adhesive lectin that can interact with various glycoconjugates. This multispecificity needs to be recognized when using PVL as a sugar-specific probe to avoid misleading information about the nature of glycoforms.

  12. Recombinant fungal lectin as a new tool to investigate O-GlcNAcylation processes.

    PubMed

    Machon, Oriane; Baldini, Steffi F; Ribeiro, João P; Steenackers, Agata; Varrot, Annabelle; Lefebvre, Tony; Imberty, Anne

    2017-01-01

    Glycosylation is a group of post-translational modifications that displays a large variety of structures and are implicated in a plethora of biological processes. Therefore, studying glycosylation requires different technical approaches and reliable tools, lectins being part of them. Here, we describe the use of the recombinant mushroom lectin PVL to discriminate O-GlcNAcylation, a modification consisting in the attachment of a single N-acetylglucosamine residue to proteins confined within the cytosolic, nuclear and mitochondrial compartments. Recombinant PVL (Psathyrella velutina lectin) (rPVL) displays significantly stronger affinity for GlcNAc over Neu5Ac residues as verified by thermal shift assays and surface plasmon resonance experiments, being therefore an excellent alternative to WGA (wheat germ agglutinin). Labeling of rPVL with biotin or HRP (horseradish peroxidase) allows its useful and efficient utilization by western blot. The staining of whole cell lysates with  labeled-rPVL was dramatically decreased in response to O-GlcNAc transferase knockdown and seen to increase after pharmacological blockade of O-GlcNAcase. Also, HRP-rPVL seemed to be more sensitive than the anti-O-GlcNAc antibody RL2. Thus, rPVL is a potent new tool to selectively detect O-GlcNAcylated proteins. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Lectin-Based Assay for Glycoform-Specific Detection of α2,6-sialylated Transferrin and Carcinoembryonic Antigen in Tissue and Body Fluid.

    PubMed

    Ito, Hiromi; Hoshi, Kyoka; Honda, Takashi; Hashimoto, Yasuhiro

    2018-05-30

    Antibodies are useful for detecting glycoprotein antigens, but a conventional antibody recognizes only a protein epitope rather than a glycan. Thus, glycan isoform detection generally requires time- and labor-consuming processes such as lectin affinity column chromatography followed by sandwich ELISA. We recently found antigen-antibody reactions that were inhibited by lectin binding to glycans on the glycoprotein antigen, leading to a convenient glycoform-specific assay. Indeed, Sambucus sieboldiana agglutinin (SSA) lectin, a binder to sialylα2,6galactose residue, inhibited antibody binding to α2,6-sialylated transferrin (Tf) (SSA inhibition). SSA inhibition was not observed with other glycoforms, such as periodate-treated, sialidase-treated and sialidase/galactosidase-treated Tf, suggesting that the assay was glycoform-specific. SSA inhibition was also applicable for visualizing localization of α2,6-sialylated-Tf in a liver section. This is the first immunohistochemical demonstration of glycoform localization in a tissue section. SSA inhibition was utilized for establishing ELISA to quantify α2,6-sialylated carcinoembryonic antigen (CEA), a marker for various cancers. In addition, α2,6-sialylated-CEA was visualized in a colonic adenocarcinoma section by SSA inhibition. The method would further be applicable to a simple and rapid estimation of other α2,6-sialylated glycoproteins and have a potential aid to histopathological diagnosis.

  14. Molecular characterization of Helja, an extracellular jacalin-related protein from Helianthus annuus: Insights into the relationship of this protein with unconventionally secreted lectins.

    PubMed

    Pinedo, Marcela; Orts, Facundo; Carvalho, André de Oliveira; Regente, Mariana; Soares, Julia Ribeiro; Gomes, Valdirene Moreira; de la Canal, Laura

    2015-07-01

    Jacalin-related lectins (JRLs) encompass cytosolic, nuclear and vacuolar members displaying the jacalin domain in one or more copies or in combination with unrelated domains. Helianthus annuus jacalin (Helja) is a mannose-specific JRL previously identified in the apoplast of Helianthus annuus seedlings, and this protein has been proposed to follow unconventional secretion. Here, we describe the full-length Helja cDNA sequence, which presents a unique jacalin domain (merolectin) and the absence of a signal peptide, confirming that the protein cannot follow the classical ER-dependent secretory pathway. Helja mRNA is present in seeds, cotyledons, roots and hypocotyls, but no transcripts were detected in the leaves. Searches for sequence similarity showed that Helja is barely similar to other JRLs present in H. annuus databases and less than 45% identical to other monocot or dicot JRLs. Strikingly, most of the merolectins recovered through data mining using Helja as a query were predicted as apoplastic, although most of these proteins lack the signal peptide required for classical secretion. Thus, Helja is the first bait identified to recover putative unconventionally secreted lectins. Because the recovered JRLs are widely distributed among the plant kingdom, an as yet unknown role for jacalin lectins in the apoplast is emerging. Copyright © 2015 Elsevier GmbH. All rights reserved.

  15. Insecticidal action of Bauhinia monandra leaf lectin (BmoLL) against Anagasta kuehniella (Lepidoptera: Pyralidae), Zabrotes subfasciatus and Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Macedo, Maria Lígia Rodrigues; das Graças Machado Freire, Maria; da Silva, Maria Barbosa Reis; Coelho, Luana Cassandra Breitenbach Barroso

    2007-04-01

    Bruchid beetle larvae cause major losses in grain legume crops throughout the world. Some bruchid species, such as the cowpea weevil (Callosobruchus maculatus) and the Mexican bean weevil (Zabrotes subfasciatus), are pests that damage stored seeds. The Mediterranean flour moth (Anagasta kuehniella) is of major economic importance as a flour and grain feeder; it is often a severe pest in flour mills. Plant lectins have been implicated as antibiosis factors against insects. Bauhinia monandra leaf lectin (BmoLL) was tested for anti-insect activity against C. maculatus, Z. subfasciatus and A. kuehniella larvae. BmoLL produced ca. 50% mortality to Z. subfaciatus and C. maculatus when incorporated into an artificial diet at a level of 0.5% and 0.3% (w/w), respectively. BmoLL up to 1% did not significantly decrease the survival of A. kuehniella larvae, but produced a decrease of 40% in weight. Affinity chromatography showed that BmoLL bound to midgut proteins of the insect C. maculatus. 33 kDa subunit BmoLL was not digested by midgut preparations of these bruchids. BmoLL-fed C. maculatus larvae increased the digestion of potato starch by 25% compared with the control. The transformation of the genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops.

  16. Jeltraxin, a frog egg jelly glycoprotein, has calcium-dependent lectin properties and is related to human serum pentraxins CRP and SAP.

    PubMed

    Peavy, Thomas R; Hernandez, Cesar; Carroll, Edward J

    2003-11-11

    The egg jelly that encapsulates amphibian eggs is essential for fertilization, but its molecular composition and roles remain largely unknown. We identified a calcium-dependent lectin from the pentraxin superfamily in the egg jelly coat from the South American burrowing frog, Lepidobatrachus laevis. This lectin, jeltraxin, was related to the host-response acute phase serum proteins C-reactive P component (CRP) and serum amyloid P component (SAP). The amino acid sequence of jeltraxin is 44% identical to that of Xenopus laevis CRP, 31-35% identical to those of mammalian CRP and SAP, and 21-27% identical to those of the large fusion pentraxins. Expression of jeltraxin mRNA was restricted to the oviduct, which distinguishes it as the first serum-related pentraxin not expressed in the liver. Purified jeltraxin was previously shown to exist in an oligomeric complex of approximately 250 kDa comprised of self-associating subunits. We have demonstrated by MALDI-TOF that this configuration is due to a decameric complex of 27.7 kDa subunits. Biotinylated jeltraxin bound to the high-molecular mass components of the egg jelly in a calcium-dependent manner with specificity for beta-galactose residues. On the basis of homology modeling, we predict that jeltraxin will coordinate two calcium ions. The function of jeltraxin will likely be related to its calcium-dependent lectin properties.

  17. Identification of cell surface glycoprotein markers for glioblastoma-derived stem-like cells using a lectin microarray and LC-MS/MS approach

    PubMed Central

    He, Jintang; Liu, Yashu; Xie, Xiaolei; Zhu, Thant; Soules, Mary; DiMeco, Francesco; Vescovi, Angelo L.; Fan, Xing; Lubman, David M.

    2010-01-01

    Despite progress in the treatment of glioblastoma, more than 95% of patients suffering from this disease still die within two years. Recent findings support the belief that cancer stem-like cells are responsible for tumor formation and ongoing growth. Here a method combining lectin microarray and LC-MS/MS was used to discover the cell surface glycoprotein markers of a glioblastoma-derived stem-like cell line. Lectin microarray analysis of cell surface glycans showed that two galactose-specific lectins Trichosanthes kirilowii agglutinin (TKA) and Peanut agglutinin (PNA) could distinguish the stem-like glioblastoma neurosphere culture from a traditional adherent glioblastoma cell line. Agarose-bound TKA and PNA were used to capture the glycoproteins from the two cell cultures, which were analyzed by LC-MS/MS. The glycoproteins were quantified by spectral counting, resulting in the identification of 12 and 11 potential glycoprotein markers from the TKA and PNA captured fractions respectively. Almost all of these proteins were membrane proteins. Differential expression was verified by Western blotting analysis of 6 interesting proteins, including the up-regulated Receptor-type tyrosine-protein phosphatase zeta, Tenascin-C, Chondroitin sulfate proteoglycan NG2, Podocalyxin-like protein 1 and CD90, and the down-regulated CD44. An improved understanding of these proteins may be important for earlier diagnosis and better therapeutic targeting of glioblastoma. PMID:20235609

  18. Characterization of the carbohydrate components of Taenia solium oncosphere proteins and their role in the antigenicity.

    PubMed

    Arana, Yanina; Verastegui, Manuela; Tuero, Iskra; Grandjean, Louis; Garcia, Hector H; Gilman, Robert H

    2013-10-01

    This study examines the carbohydrate composition of Taenia solium whole oncosphere antigens (WOAs), in order to improve the understanding of the antigenicity of the T. solium. Better knowledge of oncosphere antigens is crucial to accurately diagnose previous exposure to T. solium eggs and thus predict the development of neurocysticercosis. A set of seven lectins conjugates with wide carbohydrate specificity were used on parasite fixations and somatic extracts. Lectin fluorescence revealed that D-mannose, D-glucose, D-galactose and N-acetyl-D-galactosamine residues were the most abundant constituents of carbohydrate chains on the surface of T. solium oncosphere. Lectin blotting showed that posttranslational modification with N-glycosylation was abundant while little evidence of O-linked carbohydrates was observed. Chemical oxidation and enzymatic deglycosylation in situ were performed to investigate the immunoreactivity of the carbohydrate moieties. Linearizing or removing the carbohydrate moieties from the protein backbones did not diminish the immunoreactivity of these antigens, suggesting that a substantial part of the host immune response against T. solium oncosphere is directed against the peptide epitopes on the parasite antigens. Finally, using carbohydrate probes, we demonstrated for the first time that the presence of several lectins on the surface of the oncosphere was specific to carbohydrates found in intestinal mucus, suggesting a possible role in initial attachment of the parasite to host cells.

  19. Medicinal Properties of the Genus Clitocybe and of Lectins from the Clouded Funnel Cap Mushroom, C. nebularis (Agaricomycetes): A Review.

    PubMed

    Pohleven, Jure; Kos, Janko; Sabotic, Jerica

    2016-01-01

    Current knowledge of the medicinal properties of Basidiomycetes mushroom species of the genus Clitocybe and of the biological activity of C. nebularis fruiting bodies is reviewed. The main focus is the therapeutic potential of lectins from C. nebularis. Species of the genus Clitocybe, including C. nebularis, have not been traditionally considered as medicinal mushrooms; however, recent studies have demonstrated their antitumor, immunomodulatory, and antioxidative properties, their antimicrobial (antiviral, antibacterial, and antifungal) activities against various bacteria and fungi, as well as their potential use in therapy for alcoholism and as psychotropic agents. These activities have been shown to be due to various compounds, either isolated or in extracts, mainly polysaccharides but also phenols, ribonucleosides, and proteins. These include laccase, protease inhibitors, and lectins. C. nebularis has been shown to be rich in a variety of lectins and isolectins with distinct carbohydrate-binding specificities, showing versatile biological activities. They exhibit immunostimulatory and adhesion-/phagocytosis-promoting properties, as well as toxicity in various invertebrates. Mushroom species of the genus Clitocybe, including C. nebularis, thus constitute a valuable source of compounds showing diverse biological activities with a broad potential for applications in biomedicine or biotechnology. On the basis of such evidence reviewed here, we propose that C. nebularis and other Clitocybe species can be considered to be medicinal mushrooms.

  20. Antimicrobial lectin from Schinus terebinthifolius leaf.

    PubMed

    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.

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