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Sample records for monocot man-binding lectins

  1. Genome Size Dynamics and Evolution in Monocots

    Directory of Open Access Journals (Sweden)

    Ilia J. Leitch

    2010-01-01

    Full Text Available Monocot genomic diversity includes striking variation at many levels. This paper compares various genomic characters (e.g., range of chromosome numbers and ploidy levels, occurrence of endopolyploidy, GC content, chromosome packaging and organization, genome size between monocots and the remaining angiosperms to discern just how distinctive monocot genomes are. One of the most notable features of monocots is their wide range and diversity of genome sizes, including the species with the largest genome so far reported in plants. This genomic character is analysed in greater detail, within a phylogenetic context. By surveying available genome size and chromosome data it is apparent that different monocot orders follow distinctive modes of genome size and chromosome evolution. Further insights into genome size-evolution and dynamics were obtained using statistical modelling approaches to reconstruct the ancestral genome size at key nodes across the monocot phylogenetic tree. Such approaches reveal that while the ancestral genome size of all monocots was small (1C=1.9 pg, there have been several major increases and decreases during monocot evolution. In addition, notable increases in the rates of genome size-evolution were found in Asparagales and Poales compared with other monocot lineages.

  2. Transcript profiling of a novel plant meristem, the monocot cambium

    Science.gov (United States)

    Matthew Zinkgraf; Suzanne Gerttula; Andrew Groover

    2017-01-01

    While monocots lack the ability to produce a vascular cambium or woody growth, some monocot lineages evolved a novel lateral meristem, the monocot cambium, which supports secondary radial growth of stems. In contrast to the vascular cambium found in woody angiosperm and gymnosperm species, the monocot cambium produces secondary vascular bundles, which have an...

  3. Multiplicity of carbohydrate-binding sites in -prism fold lectins: occurrence and possible evolutionary implications

    Indian Academy of Sciences (India)

    Alok Sharma; Divya Chandran; Desh D Singh; M Vijayan

    2007-09-01

    The -prism II fold lectins of known structure, all from monocots, invariably have three carbohydrate-binding sites in each subunit/domain. Until recently, -prism I fold lectins of known structure were all from dicots and they exhibited one carbohydrate-binding site per subunit/domain. However, the recently determined structure of the -prism fold I lectin from banana, a monocot, has two very similar carbohydrate-binding sites. This prompted a detailed analysis of all the sequences appropriate for two-lectin folds and which carry one or more relevant carbohydrate-binding motifs. The very recent observation of a -prism I fold lectin, griffithsin, with three binding sites in each domain further confirmed the need for such an analysis. The analysis demonstrates substantial diversity in the number of binding sites unrelated to the taxonomical position of the plant source. However, the number of binding sites and the symmetry within the sequence exhibit reasonable correlation. The distribution of the two families of -prism fold lectins among plants and the number of binding sites in them, appear to suggest that both of them arose through successive gene duplication, fusion and divergent evolution of the same primitive carbohydrate-binding motif involving a Greek key. Analysis with sequences in individual Greek keys as independent units lends further support to this conclusion. It would seem that the preponderance of three carbohydrate-binding sites per domain in monocot lectins, particularly those with the -prism II fold, is related to the role of plant lectins in defence.

  4. TIR-NBS-LRR genes are rare in monocots: evidence from diverse monocot orders

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    Tarr D Ellen K

    2009-09-01

    Full Text Available Abstract Background Plant resistance (R gene products recognize pathogen effector molecules. Many R genes code for proteins containing nucleotide binding site (NBS and C-terminal leucine-rich repeat (LRR domains. NBS-LRR proteins can be divided into two groups, TIR-NBS-LRR and non-TIR-NBS-LRR, based on the structure of the N-terminal domain. Although both classes are clearly present in gymnosperms and eudicots, only non-TIR sequences have been found consistently in monocots. Since most studies in monocots have been limited to agriculturally important grasses, it is difficult to draw conclusions. The purpose of our study was to look for evidence of these sequences in additional monocot orders. Findings Using degenerate PCR, we amplified NBS sequences from four monocot species (C. blanda, D. marginata, S. trifasciata, and Spathiphyllum sp., a gymnosperm (C. revoluta and a eudicot (C. canephora. We successfully amplified TIR-NBS-LRR sequences from dicot and gymnosperm DNA, but not from monocot DNA. Using databases, we obtained NBS sequences from additional monocots, magnoliids and basal angiosperms. TIR-type sequences were not present in monocot or magnoliid sequences, but were present in the basal angiosperms. Phylogenetic analysis supported a single TIR clade and multiple non-TIR clades. Conclusion We were unable to find monocot TIR-NBS-LRR sequences by PCR amplification or database searches. In contrast to previous studies, our results represent five monocot orders (Poales, Zingiberales, Arecales, Asparagales, and Alismatales. Our results establish the presence of TIR-NBS-LRR sequences in basal angiosperms and suggest that although these sequences were present in early land plants, they have been reduced significantly in monocots and magnoliids.

  5. Transcript profiling of a novel plant meristem, the monocot cambium.

    Science.gov (United States)

    Zinkgraf, Matthew; Gerttula, Suzanne; Groover, Andrew

    2017-06-01

    While monocots lack the ability to produce a vascular cambium or woody growth, some monocot lineages evolved a novel lateral meristem, the monocot cambium, which supports secondary radial growth of stems. In contrast to the vascular cambium found in woody angiosperm and gymnosperm species, the monocot cambium produces secondary vascular bundles, which have an amphivasal organization of tracheids encircling a central strand of phloem. Currently there is no information concerning the molecular genetic basis of the development or evolution of the monocot cambium. Here we report high-quality transcriptomes for monocot cambium and early derivative tissues in two monocot genera, Yucca and Cordyline. Monocot cambium transcript profiles were compared to those of vascular cambia and secondary xylem tissues of two forest tree species, Populus trichocarpa and Eucalyptus grandis. Monocot cambium transcript levels showed that there are extensive overlaps between the regulation of monocot cambia and vascular cambia. Candidate regulatory genes that vary between the monocot and vascular cambia were also identified, and included members of the KANADI and CLE families involved in polarity and cell-cell signaling, respectively. We suggest that the monocot cambium may have evolved in part through reactivation of genetic mechanisms involved in vascular cambium regulation. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  6. Extensins in graminaceous monocots and dicots compared

    Energy Technology Data Exchange (ETDEWEB)

    Kieliszewski, M.; Lamport, D.T.A.

    1987-04-01

    Is the cellulose-extensin warp-weft model of primary cell wall organization generally applicable, or restricted to dicots. Although wall-bound hydroxyproline is usually a quantitative measure of extensin content, it is not definitive at low hyp levels typical of graminaceous monocots. Therefore the authors searched for putative soluble extensins ionically-bound to the cell wall of maize cell suspension cultures. Fractionation of AlCl/sub 3/ eluates on cellex-P, Cellex-E, and Superose-6 gave two HRGPs CEV and CE1 which compositionally resembled extensins rather than the arabinogalactan HRGPs. CEV and CE1 did not react with Yariv's antigen, but did cross-react with antibodies raised against tomato extensin. A tryptic peptide map of CEV gave some major peptides enriched in hydroxyproline and proline residues, indicating peptide periodicity. TEM of the low-angle shadowed protein gave flexuous rodlike molecules of 80 nm contour length. This is the best evidence to date for extensin in monocots.

  7. Do global diversity patterns of vertebrates reflect those of monocots?

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    Lynsey McInnes

    Full Text Available Few studies of global diversity gradients in plants exist, largely because the data are not available for all species involved. Instead, most global studies have focussed on vertebrates, as these taxa have historically been associated with the most complete data. Here, we address this shortfall by first investigating global diversity gradients in monocots, a morphologically and functionally diverse clade representing a quarter of flowering plant diversity, and then assessing congruence between monocot and vertebrate diversity patterns. To do this, we create a new dataset that merges biome-level associations for all monocot genera with country-level associations for almost all ∼70,000 species. We then assess the evidence for direct versus indirect effects of this plant diversity on vertebrate diversity using a combination of linear regression and structural equation modelling (SEM. Finally, we also calculate overlap of diversity hotspots for monocots and each vertebrate taxon. Monocots follow a latitudinal gradient although with pockets of extra-tropical diversity, mirroring patterns in vertebrates. Monocot diversity is positively associated with vertebrate diversity, but the strength of correlation varies depending on the clades being compared. Monocot diversity explains marginal amounts of variance (<10% after environmental factors have been accounted for. However, correlations remain among model residuals, and SEMs apparently reveal some direct effects of monocot richness. Our results suggest that collinear responses to environmental gradients are behind much of the congruence observed, but that there is some evidence for direct effects of producer diversity on consumer diversity. Much remains to be done before broad-scale diversity gradients among taxa are fully explained. Our dataset of monocot distributions will aid in this endeavour.

  8. Cercosporoid fungi (Mycosphaerellaceae) 3. Species on monocots (Poaceae, true grasses)

    NARCIS (Netherlands)

    Braun, Uwe; Crous, Pedro W; Nakashima, Chiharu

    The third part of a series of monographic treatments of cercosporoid fungi (formerly Cercospora s. lat., Mycosphaerellaceae, Ascomycota) continues with a treatment of taxa on monocots (Liliopsida; Equisetopsida, Magnoliidae, Lilianae), covering asexual and holomorph species with mycosphaerella-like

  9. Molecular basis of development in petaloid monocot flowers

    DEFF Research Database (Denmark)

    Johansen, Bo; Frederiksen, Signe; Skipper, Martin

    2006-01-01

    -class genes and at least two copies of A-class genes: one is expressed in floral meristems, the other in inflorescence meristems. In monocots and non-core eudicots the validity of the ABC model is under discussion. Generally, more than one functional copy is found of at least one of the B-class genes. The A......-class genes apparently are expressed in meristems of both flower and inflorescence. Morphologically petaloid stamens and styles are well known within the petaloid monocots, whereas the phenomenon is rare in core eudicots. A simple model based on the extra copies of B-class genes can explain the molecular...

  10. Isolation and characterization of a new mannose-binding lectin gene from Taxus media

    Indian Academy of Sciences (India)

    Guoyin Kai; Lingxia Zhao; Jingui Zheng; Lei Zhang; Zhiqi Miao; Xiaofen Sun; Kexuan Tanga

    2004-12-01

    In this paper, we report the cloning and characterization of the first mannose-binding lectin gene from a gymnosperm plant species, Taxus media. The full-length cDNA of T. media agglutinin (TMA) consisted of 676 bp and contained a 432 bp open reading frame (ORF) encoding a 144 amino acid protein. Comparative analysis showed that TMA had high homology with many previously reported plant mannose-binding lectins and that tma encoded a precursor lectin with a 26-aa signal peptide. Molecular modelling revealed that TMA was a new mannose-binding lectin with three typical mannose-binding boxes like lectins from species of angiosperms. Tissue expression pattern analyses revealed that tma is expressed in a tissue-specific manner in leaves and stems, but not in fruits and roots. Phylogenetic tree analyses showed that TMA belonged to the structurally and evolutionarily closely related monocot mannose-binding lectin superfamily. This study provides useful information to understand the molecular evolution of plant lectins.

  11. PERIANTH DEVELOPMENT IN THE BASAL MONOCOT TRIGLOCHIN MARITIMA (JUNCAGINACEAE)

    DEFF Research Database (Denmark)

    Buzgo, Matyas; Soltis, Douglas E.; Soltis, Pamela S.;

    2006-01-01

    Basal monocots exhibit considerable variation in inflorescence and floral structure. In some cases, such as Triglochin maritima, it is not clear whether the lateral and terminal structures of the inflores- cence are flowers or pseudanthia, or where the limits between flowers and inflorescence lie...

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

    Science.gov (United States)

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

    2000-01-01

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

  13. Molecular cloning and characterization of a novel mannose-binding lectin gene from Amorphophallus konjac.

    Science.gov (United States)

    Fei, Jiong; Liao, Zhihua; Chai, Yourong; Pang, Yongzhen; Yao, Jianhong; Sun, Xiaofen; Tang, Kexuan

    2003-09-01

    A new lectin gene was cloned from Amorphophallus konjac. The full-length cDNA of Amorphophallus konjac agglutinin (aka) was 736 bp and contained a 474 bp open reading frame encoding a 158 amino acid protein. Homology analysis revealed that the lectin from this Araceae species belonged to the superfamily of monocot mannose-binding proteins. Molecular modeling of AKA indicated that the three-dimensional structure of AKA strongly resembles that of the snowdrop lectin. Southern blot analysis of the genomic DNA revealed that aka belonged to a low-copy gene family. Northern blot analysis demonstrated that aka expression was tissue-specific with the strongest expression being found in root.

  14. cDNA cloning and characterization of a mannose-binding lectin from Zingiber officinale Roscoe (ginger) rhizomes

    Indian Academy of Sciences (India)

    Zhonghai Chen; Guoyin Kai; Xiaojun Liu; Juan Lin; Xiaofen Sun; Kexuan Tang

    2005-03-01

    Using RNA extracted from Zingiber officinale rhizomes and primers designed according to the conservative regions of monocot mannose-binding lectins, the full-length cDNA of Z. officinale agglutinin (ZOA) was cloned by rapid amplification of cDNA ends (RACE). The full-length cDNA of zoa was 746 bp and contained a 510 bp open reading frame (ORF) encoding a lectin precursor of 169 amino acids with a signal peptide. ZOA was a mannose-binding lectin with three typical mannose-binding sites (QDNY). Semi-quantitative RT-PCR analysis revealed that zoa expressed in all the tested tissues of Z. officinale including leaf, root and rhizome, suggesting it to be a constitutively expressing form. ZOA protein was successfully expressed in Escherichia coli with the molecular weight expected. To our knowledge, this is the first mannose-binding lectin cDNA cloned from the family Zingiberaceae. Our results demonstrate that monocot mannose-binding lectins also occur within the family Zingiberaceae.

  15. The role of auxin transporters in monocots development

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    Sara eBalzan

    2014-08-01

    Full Text Available Auxin is a key regulator of plant growth and development, orchestrating cell division, elongation and differentiation, embryonic development, root and stem tropisms, apical dominance and transition to flowering. Auxin levels are higher in undifferentiated cell populations and decrease following organ initiation and tissue differentiation. This differential auxin distribution is achieved by polar auxin transport (PAT mediated by auxin transport proteins. There are 4 major families of auxin transporters in plants: PINs, ABCBs, AUX/LAXs and PILS. These families include proteins located at the plasma membrane (PM or at the Endoplasmic Reticulum (ER, which participate in auxin influx, efflux or both, from the apoplast into the cell or from the cytosol into the ER compartment. Auxin transporters have been largely studied in the dicotyledon model species Arabidopsis, but there is increasing evidence of their role in auxin regulated development in monocotyledon species. In monocots, families of auxin transporters are enlarged and often include duplicated genes and proteins with high sequence similarity. Some of these proteins underwent sub- and neo-functionalization with substantial modification to their structure and expression in organs such as adventitious roots, panicles, tassels and ears. Most of the present information on monocot auxin transporters function derives from studies conducted in rice, maize, sorghum and Brachypodium using pharmacological applications (PAT inhibitors or down-/up-regulation (over-expression and RNAi of candidate genes. Gene expression studies and comparison of predicted protein structures have also increased our knowledge of the role of PAT in monocots. However, knockout mutants and functional characterization of single genes are still scarce and the future availability of such resources will prove crucial to elucidate the role of auxin transporters in monocot development.

  16. Lectins with Anti-HIV Activity: A Review

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    Ouafae Akkouh

    2015-01-01

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

  17. Morphogenic Regulators Baby boom and Wuschel Improve Monocot Transformation.

    Science.gov (United States)

    Lowe, Keith; Wu, Emily; Wang, Ning; Hoerster, George; Hastings, Craig; Cho, Myeong-Je; Scelonge, Chris; Lenderts, Brian; Chamberlin, Mark; Cushatt, Josh; Wang, Lijuan; Ryan, Larisa; Khan, Tanveer; Chow-Yiu, Julia; Hua, Wei; Yu, Maryanne; Banh, Jenny; Bao, Zhongmeng; Brink, Kent; Igo, Elizabeth; Rudrappa, Bhojaraja; Shamseer, P M; Bruce, Wes; Newman, Lisa; Shen, Bo; Zheng, Peizhong; Bidney, Dennis; Falco, S Carl; RegisterIII, James C; Zhao, Zuo-Yu; Xu, Deping; Jones, Todd J; Gordon-Kamm, William James

    2016-09-06

    While transformation of the major monocot crops is currently possible, the process typically remains confined to one or two genotypes per species, often with poor agronomics, and efficiencies that place these methods beyond the reach of most academic laboratories. Here, we report a transformation approach involving overexpression of the maize (Zea mays) Baby boom (Bbm) and maize Wuschel2 (Wus2) genes, which produced high transformation frequencies in numerous previously non-transformable maize inbred lines. For example, the Pioneer inbred PHH5G is recalcitrant to biolistic and Agrobacterium transformation. However, when Bbm and Wus2 were expressed, transgenic calli were recovered from over 40% of the starting explants, with most producing healthy, fertile plants. Another limitation for many monocots is the intensive labor and greenhouse space required to supply immature embryos for transformation. This problem could be alleviated by using alternative target tissues that could be supplied consistently with automated preparation. As a major step toward this objective, we transformed Bbm and Wus2 directly into either embryo slices from mature seed or leaf segments from seedlings in a variety of Pioneer inbred lines, routinely recovering healthy, fertile T0 plants. Finally, we demonstrated that the maize Bbm and Wus2 genes stimulate transformation in sorghum (Sorghum bicolor) immature embryos, sugarcane (Saccharum officinarum) callus, and indica rice (Oryza sativa var. indica) callus. {copyright, serif} 2016 American Society of Plant Biologists. All rights reserved.

  18. Motif content comparison between monocot and dicot species

    Directory of Open Access Journals (Sweden)

    Matyas Cserhati

    2015-03-01

    Full Text Available While a number of DNA sequence motifs have been functionally characterized, the full repertoire of motifs in an organism (the motifome is yet to be characterized. The present study wishes to widen the scope of motif content analysis in different monocot and dicot species that include both rice species, Brachypodium, corn, wheat as monocots and Arabidopsis, Lotus japonica, Medicago truncatula, and Populus tremula as dicots. All possible existing motifs were analyzed in different regions of genomes such as were found in different sets of sequences in these species: the whole genome, core proximal and distal promoters, 5′ and 3′ UTRs, and the 1st introns. Due to the increased number of species involved in this study compared to previous works, species relationships were analyzed based on the similarity of common motif content. Certain secondary structure elements were inferred in the genomes of these species as well as new unknown motifs. The distribution of 20 motifs common to the studied species were found to have a significantly larger occurrence within the promoters and 3′ UTRs of genes, both being regulatory regions. Motifs common to the promoter regions of japonica rice, Brachypodium, and corn were also found in a number of orthologous and paralogous genes. Some of our motifs were found to be complementary to miRNA elements in Brachypodium distachyon and japonica rice.

  19. Structural characterisation of the native fetuin-binding protein Scilla campanulata agglutinin: a novel two-domain lectin.

    Science.gov (United States)

    Wright, L M; Reynolds, C D; Rizkallah, P J; Allen, A K; Van Damme, E J; Donovan, M J; Peumans, W J

    2000-02-18

    The three-dimensional structure of a 244-residue, multivalent, fetuin-binding lectin, SCAfet, isolated from bluebell (Scilla campanulata) bulbs, has been solved at 3.3 A resolution by molecular replacement using the coordinates of the 119-residue, mannose-binding lectin, SCAman, also from bluebell bulbs. Unlike most monocot mannose-binding lectins, such as Galanthus nivalis agglutinin from snowdrop bulbs, which fold into a single domain, SCAfet contains two domains with approximately 55% sequence identity, joined by a linker peptide. Both domains are made up of a 12-stranded beta-prism II fold, with three putative carbohydrate-binding sites, one on each subdomain. SCAfet binds to the complex saccharides of various animal glycoproteins but not to simple sugars.

  20. Structural basis of oligomannose recognition by the Pterocarpus angolensis seed lectin.

    Science.gov (United States)

    Loris, Remy; Van Walle, Ivo; De Greve, Henri; Beeckmans, Sonia; Deboeck, Francine; Wyns, Lode; Bouckaert, Julie

    2004-01-30

    The crystal structure of a Man/Glc-specific lectin from the seeds of the bloodwood tree (Pterocarpus angolensis), a leguminous plant from central Africa, has been determined in complex with mannose and five manno-oligosaccharides. The lectin contains a classical mannose-specificity loop, but its metal-binding loop resembles that of lectins of unrelated specificity from Ulex europaeus and Maackia amurensis. As a consequence, the interactions with mannose in the primary binding site are conserved, but details of carbohydrate-binding outside the primary binding site differ from those seen in the equivalent carbohydrate complexes of concanavalin A. These observations explain the differences in their respective fine specificity profiles for oligomannoses. While Man(alpha1-3)Man and Man(alpha1-3)[Man(alpha1-6)]Man bind to PAL in low-energy conformations identical with that of ConA, Man(alpha1-6)Man is required to adopt a different conformation. Man(alpha1-2)Man can bind only in a single binding mode, in sharp contrast to ConA, which creates a higher affinity for this disaccharide by allowing two binding modes.

  1. Molecular dynamics simulations and MM-PBSA calculations of the lectin from snowdrop (Galanthus nivalis).

    Science.gov (United States)

    Liu, Zhen; Zhang, Yizheng

    2009-12-01

    Galanthus nivalis agglutinin (GNA), a mannose-specific lectin from snowdrop bulbs, is a member of the monocot mannose-specific lectin family and exhibits antiviral activity toward HIV. In the present study, molecular dynamics (MD) simulations were performed to study the interaction between GNA and its carbohydrate ligand over a specific time span. By analysis of the secondary structures, it was observed that the GNA conformation maintains rather stable along the trajectories and the high fluctuations were only centered on the carbohydrate recognition domains. Our MD simulations also reproduced most of the hydrogen bonds observed in the x-ray crystal structure. Furthermore, the obtained MD trajectories were used to estimate the binding free energy of the complex using the molecular mechanics/Poisson Boltzmann surface area (MM-PBSA) method. It was revealed by the inspection of the binding free energy components that the major contributions to the complex stability arose from electrostatic interactions.

  2. Cercosporoid fungi (Mycosphaerellaceae) 3. Species on monocots (Poaceae, true grasses).

    Science.gov (United States)

    Braun, Uwe; Crous, Pedro W; Nakashima, Chiharu

    2015-06-01

    The third part of a series of monographic treatments of cercosporoid fungi (formerly Cercospora s. lat., Mycosphaerellaceae, Ascomycota) continues with a treatment of taxa on monocots (Liliopsida; Equisetopsida, Magnoliidae, Lilianae), covering asexual and holomorph species with mycosphaerella-like sexual morphs on true grasses (Poaceae), which were excluded from the second part. The species concerned are keyed out, alphabetically listed, described, illustrated and supplemented by references to previously published descriptions, illustrations, and exsiccatae. A key to the recognised genera and a discussion of taxonomically relevant characters was published in the first part of this series. Several species are lecto- or neotypified. The following taxonomic novelties are introduced: Cercospora barretoana comb. nov., C. cymbopogonicola nom. nov., Cladosporium elymi comb. nov., Passalora agrostidicola sp. nov., P. brachyelytri comb. nov., and P. dichanthii-annulati comb. nov.

  3. Lectins from Mycelia of Basidiomycetes

    Directory of Open Access Journals (Sweden)

    Valentina E. Nikitina

    2017-06-01

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

  4. Glycan and lectin biosensors

    Science.gov (United States)

    Belický, Štefan; Katrlík, Jaroslav

    2016-01-01

    A short description about the importance of glycan biorecognition in physiological (blood cell type) and pathological processes (infections by human and avian influenza viruses) is provided in this review. Glycans are described as much better information storage media, compared to proteins or DNA, due to the extensive variability of glycan structures. Techniques able to detect an exact glycan structure are briefly discussed with the main focus on the application of lectins (glycan-recognising proteins) in the specific analysis of glycans still attached to proteins or cells/viruses. Optical, electrochemical, piezoelectric and micromechanical biosensors with immobilised lectins or glycans able to detect a wide range of analytes including whole cells/viruses are also discussed. PMID:27365034

  5. Lectin typing of Campylobacter concisus

    DEFF Research Database (Denmark)

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

    2002-01-01

    A total of 44 clinical isolates and the type strain of the putative pathogen Campylobacter concisus were grouped based on their reactions with plant lectins. The optimized lectin typing system used C. concisus strains proteolytically pretreated and subsequently typed by using a panel of four...

  6. The lectin pathway of complement

    DEFF Research Database (Denmark)

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

    2014-01-01

    The pattern recognition molecules of the lectin complement pathway are important components of the innate immune system with known functions in host-virus interactions. This paper summarizes current knowledge of how these intriguing molecules, including mannose-binding lectin (MBL), Ficolin-1, -2...

  7. Wetland dicots and monocots differ in colonization by arbuscular mycorrhizal fungi and dark septate endophytes.

    Science.gov (United States)

    Weishampel, Peter A; Bedford, Barbara L

    2006-10-01

    As an initial step towards evaluating whether mycorrhizas influence composition and diversity in calcareous fen plant communities, we surveyed root colonization by arbuscular mycorrhizal fungi (AMF) and dark septate endophytic fungi (DSE) in 67 plant species in three different fens in central New York State (USA). We found colonization by AMF and DSE in most plant species at all three sites, with the type and extent of colonization differing between monocots and dicots. On average, AMF colonization was higher in dicots (58+/-3%, mean+/-SE) than in monocots (13+/-4%) but DSE colonization followed the opposite trend (24+/-3% in monocots and 9+/-1% in dicots). In sedges and cattails, two monocot families that are often abundant in fens and other wetlands, AMF colonization was usually very low (<10%) in five species and completely absent in seven others. However, DSE colonization in these species was frequently observed. Responses of wetland plants to AMF and DSE are poorly understood, but in the fen communities surveyed, dicots appear to be in a better position to respond to AMF than many of these more abundant monocots (e.g., sedges and cattails). In contrast, these monocots may be more likely to respond to DSE. Future work directed towards understanding the response of these wetland plants to AMF and DSE should provide insight into the roles these fungal symbionts play in influencing diversity in fen plant communities.

  8. Lectins and Tetrahymena - A review.

    Science.gov (United States)

    Csaba, György

    2016-09-01

    The unicellular ciliate Tetrahymena is a complete organism, one of the most highly developed protozoans, which has specialized organelles performing each of the functions characteristic to the cells of higher ranked animals. It is also able to produce, store, and secrete hormones of higher ranked animals and also react to them. It produces lectins that can bind them and has functions, which are influenced by exogenous lectins. The review lists the observations on the relationship between lectins and Tetrahymena and try to construe them on the basis of the data, which are at our disposal. Considering the data, lectins can be used by Tetrahymena as materials for influencing conjugation, for stimulating hormone receptors, and by this, mimic the hormonal functions. Lectins can influence phagocytosis and movement of the cells as well as the cell division. As Tetrahymena can recognize both related and hostile cells by the help of lectins and surface sugars, it could be surmised a complex predator-prey system. This could determine the survival of the population as well as the nourishment conditions. When Tetrahymena is pathogenic, it can use lectins as virulence factors.

  9. DNA barcoding of the Lemnaceae, a family of aquatic monocots

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    Wang Wenqin

    2010-09-01

    Full Text Available Abstract Background Members of the aquatic monocot family Lemnaceae (commonly called duckweeds represent the smallest and fastest growing flowering plants. Their highly reduced morphology and infrequent flowering result in a dearth of characters for distinguishing between the nearly 38 species that exhibit these tiny, closely-related and often morphologically similar features within the same family of plants. Results We developed a simple and rapid DNA-based molecular identification system for the Lemnaceae based on sequence polymorphisms. We compared the barcoding potential of the seven plastid-markers proposed by the CBOL (Consortium for the Barcode of Life plant-working group to discriminate species within the land plants in 97 accessions representing 31 species from the family of Lemnaceae. A Lemnaceae-specific set of PCR and sequencing primers were designed for four plastid coding genes (rpoB, rpoC1, rbcL and matK and three noncoding spacers (atpF-atpH, psbK-psbI and trnH-psbA based on the Lemna minor chloroplast genome sequence. We assessed the ease of amplification and sequencing for these markers, examined the extent of the barcoding gap between intra- and inter-specific variation by pairwise distances, evaluated successful identifications based on direct sequence comparison of the "best close match" and the construction of a phylogenetic tree. Conclusions Based on its reliable amplification, straightforward sequence alignment, and rates of DNA variation between species and within species, we propose that the atpF-atpH noncoding spacer could serve as a universal DNA barcoding marker for species-level identification of duckweeds.

  10. Use of lectins in immunohematology

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    Ajit C Gorakshakar

    2016-01-01

    Full Text Available Lectins are carbohydrate binding proteins present in seeds of many plants, especially corals and beans, in fungi and bacteria, and in animals. Apart from their hemagglutinating property, a wide range of functions have been attributed to them. Their importance in the area of immunohematology is immense. They are used to detect specific red cell antigens, to activate different types of lymphocytes, in order to resolve problems related to polyagglutination and so on. The introduction of advanced biotechnological tools generates new opportunities to exploit the properties of lectins, which were not used earlier. Stem cell research is a very important area in transplant medicine. Certain lectins detect surface markers of stem cell. Hence, they are used to understand the developmental biology of stem cells. The role of various lectins in the areas of transfusion and transplant medicine is discussed in detail in this review.

  11. Lectins in human pathogenic fungi.

    Science.gov (United States)

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

    2014-01-01

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

  12. Lectin-probed western blot analysis.

    Science.gov (United States)

    Sato, Takeshi

    2014-01-01

    Lectin-probed western blot analysis, the so-called lectin blot analysis, is a useful method to yield basic information on the glycan structures of glycoproteins, based on the carbohydrate-binding specificities of lectins. By lectin blot analysis, researchers can directly analyze the glycan structures without releasing the glycans from glycoproteins. Here, the author describes protocols for standard analysis, and applies analysis in combination with glycosidase digestion of blot.

  13. Dynamics and evolution of the inverted repeat-large single copy junctions in the chloroplast genomes of monocots

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    Wu Chun-Lin

    2008-01-01

    Full Text Available Abstract Background Various expansions or contractions of inverted repeats (IRs in chloroplast genomes led to fluxes in the IR-LSC (large single copy junctions. Previous studies revealed that some monocot IRs contain a trnH-rps19 gene cluster, and it has been speculated that this may be an evidence of a duplication event prior to the divergence of monocot lineages. Therefore, we compared the organizations of genes flanking two IR-LSC junctions in 123 angiosperm representatives to uncover the evolutionary dynamics of IR-LSC junctions in basal angiosperms and monocots. Results The organizations of genes flanking IR-LSC junctions in angiosperms can be classified into three types. Generally each IR of monocots contains a trnH-rps19 gene cluster near the IR-LSC junctions, which differs from those in non-monocot angiosperms. Moreover, IRs expanded more progressively in monocots than in non-monocot angiosperms. IR-LSC junctions commonly occurred at polyA tract or A-rich regions in angiosperms. Our RT-PCR assays indicate that in monocot IRA the trnH-rps19 gene cluster is regulated by two opposing promoters, S10A and psbA. Conclusion Two hypotheses are proposed to account for the evolution of IR expansions in monocots. Based on our observations, the inclusion of a trnH-rps19 cluster in majority of monocot IRs could be reasonably explained by the hypothesis that a DSB event first occurred at IRB and led to the expansion of IRs to trnH, followed by a successive DSB event within IRA and lead to the expansion of IRs to rps19 or to rpl22 so far. This implies that the duplication of trnH-rps19 gene cluster was prior to the diversification of extant monocot lineages. The duplicated trnH genes in the IRB of most monocots and non-monocot angiosperms have distinct fates, which are likely regulated by different expression levels of S10A and S10B promoters. Further study is needed to unravel the evolutionary significance of IR expansion in more recently diverged

  14. New mannose-binding lectin isolated from the rhizome of Sarsaparilla Smilax glabra Roxb. (Liliaceae).

    Science.gov (United States)

    Ooi, Linda S M; Sun, Samuel S M; Wang, Hua; Ooi, Vincent E C

    2004-10-06

    A new mannose-binding lectin, designated SGM2, was isolated from the rhizome of a Chinese medicinal herb Smilax glabra (also known as sarsaparilla in general) by saline extraction, ammonium sulfate precipitation and fractionation, and affinity chromatography on fetuin- and mannose-agarose. SGM2 is shown to have a molecular mass of 37 kDa on gel filtration and 12.5 kDa on SDS-PAGE, indicating that it is a trimeric protein composed of three identical subunits. When the first 30 amino acid residues at the N-terminal were compared, SGM2 had approximately 40% homology with those of some other monocots. SGM2 had the property of hemagglutinating activity toward rabbit erythrocytes, which could be reversed by mannose and mannose polymers. SGM2 exhibited antiviral activities against both herpes simplex virus type 1 (HSV-1) and respiratory syncytial virus (RSV) with the same EC(50) of 8.1 microM.

  15. Biological role of lectins: A review

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    K Kiran Kumar

    2012-01-01

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

  16. Evaluation of Monocot and Eudicot Divergence Using the Sugarcane Transcriptome1[w

    Science.gov (United States)

    Vincentz, Michel; Cara, Frank A.A.; Okura, Vagner K.; da Silva, Felipe R.; Pedrosa, Guilherme L.; Hemerly, Adriana S.; Capella, Adriana N.; Marins, Mozart; Ferreira, Paulo C.; França, Suzelei C.; Grivet, Laurent; Vettore, Andre L.; Kemper, Edson L.; Burnquist, Willian L.; Targon, Maria L.P.; Siqueira, Walter J.; Kuramae, Eiko E.; Marino, Celso L.; Camargo, Luis E.A.; Carrer, Helaine; Coutinho, Luis L.; Furlan, Luiz R.; Lemos, Manoel V.F.; Nunes, Luiz R.; Gomes, Suely L.; Santelli, Roberto V.; Goldman, Maria H.; Bacci, Maurício; Giglioti, Eder A.; Thiemann, Otávio H.; Silva, Flávio H.; Van Sluys, Marie-Anne; Nobrega, Francisco G.; Arruda, Paulo; Menck, Carlos F.M.

    2004-01-01

    Over 40,000 sugarcane (Saccharum officinarum) consensus sequences assembled from 237,954 expressed sequence tags were compared with the protein and DNA sequences from other angiosperms, including the genomes of Arabidopsis and rice (Oryza sativa). Approximately two-thirds of the sugarcane transcriptome have similar sequences in Arabidopsis. These sequences may represent a core set of proteins or protein domains that are conserved among monocots and eudicots and probably encode for essential angiosperm functions. The remaining sequences represent putative monocot-specific genetic material, one-half of which were found only in sugarcane. These monocot-specific cDNAs represent either novelties or, in many cases, fast-evolving sequences that diverged substantially from their eudicot homologs. The wide comparative genome analysis presented here provides information on the evolutionary changes that underlie the divergence of monocots and eudicots. Our comparative analysis also led to the identification of several not yet annotated putative genes and possible gene loss events in Arabidopsis. PMID:15020759

  17. Long branch attraction, taxon sampling, and the earliest angiosperms: Amborella or monocots?

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    Rice Danny W

    2004-09-01

    Full Text Available Abstract Background Numerous studies, using in aggregate some 28 genes, have achieved a consensus in recognizing three groups of plants, including Amborella, as comprising the basal-most grade of all other angiosperms. A major exception is the recent study by Goremykin et al. (2003; Mol. Biol. Evol. 20:1499–1505, whose analyses of 61 genes from 13 sequenced chloroplast genomes of land plants nearly always found 100% support for monocots as the deepest angiosperms relative to Amborella, Calycanthus, and eudicots. We hypothesized that this conflict reflects a misrooting of angiosperms resulting from inadequate taxon sampling, inappropriate phylogenetic methodology, and rapid evolution in the grass lineage used to represent monocots. Results We used two main approaches to test this hypothesis. First, we sequenced a large number of chloroplast genes from the monocot Acorus and added these plus previously sequenced Acorus genes to the Goremykin et al. (2003 dataset in order to explore the effects of altered monocot sampling under the same analytical conditions used in their study. With Acorus alone representing monocots, strongly supported Amborella-sister trees were obtained in all maximum likelihood and parsimony analyses, and in some distance-based analyses. Trees with both Acorus and grasses gave either a well-supported Amborella-sister topology or else a highly unlikely topology with 100% support for grasses-sister and paraphyly of monocots (i.e., Acorus sister to "dicots" rather than to grasses. Second, we reanalyzed the Goremykin et al. (2003 dataset focusing on methods designed to account for rate heterogeneity. These analyses supported an Amborella-sister hypothesis, with bootstrap support values often conflicting strongly with cognate analyses performed without allowing for rate heterogeneity. In addition, we carried out a limited set of analyses that included the chloroplast genome of Nymphaea, whose position as a basal angiosperm was

  18. Long branch attraction, taxon sampling, and the earliest angiosperms: Amborella or monocots?

    Science.gov (United States)

    Stefanović, Saša; Rice, Danny W; Palmer, Jeffrey D

    2004-01-01

    Background Numerous studies, using in aggregate some 28 genes, have achieved a consensus in recognizing three groups of plants, including Amborella, as comprising the basal-most grade of all other angiosperms. A major exception is the recent study by Goremykin et al. (2003; Mol. Biol. Evol. 20:1499–1505), whose analyses of 61 genes from 13 sequenced chloroplast genomes of land plants nearly always found 100% support for monocots as the deepest angiosperms relative to Amborella, Calycanthus, and eudicots. We hypothesized that this conflict reflects a misrooting of angiosperms resulting from inadequate taxon sampling, inappropriate phylogenetic methodology, and rapid evolution in the grass lineage used to represent monocots. Results We used two main approaches to test this hypothesis. First, we sequenced a large number of chloroplast genes from the monocot Acorus and added these plus previously sequenced Acorus genes to the Goremykin et al. (2003) dataset in order to explore the effects of altered monocot sampling under the same analytical conditions used in their study. With Acorus alone representing monocots, strongly supported Amborella-sister trees were obtained in all maximum likelihood and parsimony analyses, and in some distance-based analyses. Trees with both Acorus and grasses gave either a well-supported Amborella-sister topology or else a highly unlikely topology with 100% support for grasses-sister and paraphyly of monocots (i.e., Acorus sister to "dicots" rather than to grasses). Second, we reanalyzed the Goremykin et al. (2003) dataset focusing on methods designed to account for rate heterogeneity. These analyses supported an Amborella-sister hypothesis, with bootstrap support values often conflicting strongly with cognate analyses performed without allowing for rate heterogeneity. In addition, we carried out a limited set of analyses that included the chloroplast genome of Nymphaea, whose position as a basal angiosperm was also, and very recently

  19. Bayesian phylogeny of sucrose transporters: Ancient origins, differential expansion and convergent evolution in monocots and dicots

    Directory of Open Access Journals (Sweden)

    Duo ePeng

    2014-11-01

    Full Text Available Sucrose transporters (SUTs are essential for the export and efficient movement of sucrose from source leaves to sink organs in plants. The angiosperm SUT family was previously classified into three or four distinct groups, Types I, II (subgroup IIB and III, with dicot-specific Type I and monocot-specific Type IIB functioning in phloem loading. To shed light on the underlying drivers of SUT evolution, Bayesian phylogenetic inference was undertaken using 41 sequenced plant genomes, including seven basal lineages at key evolutionary junctures. Our analysis supports four phylogenetically and structurally distinct SUT subfamilies, originating from two ancient groups (AG1 and AG2 that diverged early during terrestrial colonization. In both AG1 and AG2, multiple intron acquisition events in the progenitor vascular plant established the gene structures of modern SUTs. Tonoplastic Type III and plasmalemmal Type II represent evolutionarily conserved descendants of AG1 and AG2, respectively. Type I and Type IIB were previously thought to evolve after the dicot-monocot split. We show, however, that divergence of Type I from Type III SUT predated basal angiosperms, likely associated with evolution of vascular cambium and phloem transport. Type I SUT was subsequently lost in monocots along with vascular cambium, and independent evolution of Type IIB coincided with modified monocot vasculature. Both Type I and Type IIB underwent lineage-specific expansion. In multiple unrelated taxa, the newly-derived SUTs exhibit biased expression in reproductive tissues, suggesting a functional link between phloem loading and reproductive fitness. Convergent evolution of Type I and Type IIB for SUT function in phloem loading and reproductive organs supports the idea that differential vascular development in dicots and monocots is a strong driver for SUT family evolution in angiosperms.

  20. Genome-wide computational prediction and analysis of core promoter elements across plant monocots and dicots.

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    Sunita Kumari

    Full Text Available Transcription initiation, essential to gene expression regulation, involves recruitment of basal transcription factors to the core promoter elements (CPEs. The distribution of currently known CPEs across plant genomes is largely unknown. This is the first large scale genome-wide report on the computational prediction of CPEs across eight plant genomes to help better understand the transcription initiation complex assembly. The distribution of thirteen known CPEs across four monocots (Brachypodium distachyon, Oryza sativa ssp. japonica, Sorghum bicolor, Zea mays and four dicots (Arabidopsis thaliana, Populus trichocarpa, Vitis vinifera, Glycine max reveals the structural organization of the core promoter in relation to the TATA-box as well as with respect to other CPEs. The distribution of known CPE motifs with respect to transcription start site (TSS exhibited positional conservation within monocots and dicots with slight differences across all eight genomes. Further, a more refined subset of annotated genes based on orthologs of the model monocot (O. sativa ssp. japonica and dicot (A. thaliana genomes supported the positional distribution of these thirteen known CPEs. DNA free energy profiles provided evidence that the structural properties of promoter regions are distinctly different from that of the non-regulatory genome sequence. It also showed that monocot core promoters have lower DNA free energy than dicot core promoters. The comparison of monocot and dicot promoter sequences highlights both the similarities and differences in the core promoter architecture irrespective of the species-specific nucleotide bias. This study will be useful for future work related to genome annotation projects and can inspire research efforts aimed to better understand regulatory mechanisms of transcription.

  1. Lectins as markers for blood grouping.

    Science.gov (United States)

    Khan, Fauzia; Khan, Rizwan H; Sherwani, Asma; Mohmood, Sameena; Azfer, Md A

    2002-12-01

    Lectins are unique proteins of varying biological importance. They are characterized by specific binding to carbohydrate residues, whether monosaccharides, disaccharides or polysaccharides. The sugar heads on the surface of the erythrocyte specify the different blood groups. Lectins, as an antigenic determinant of blood group, have come to be an important tool in the identification of different blood groups. A handful of lectins may be considered excellent reagents for anti-A, anti-B, anti-N etc, but the anti-A and anti-M are not yet regarded as commercially suitable antisera. Lectin from Vicia cracca has been proved to be a good anti-A, lectin from Dolichus biflorus can be used as anti-A1, and lectin from Griffonia simplicifolia as anti-B. Lectin from Vicia graminea is said to be a good typing reagent as Anti-N. On the other hand, the lectins involved in polyagglutination are absolutely essential as the reagent of choice and these cannot as yet be replaced by antibodies of any kind. Erythrocytes with exposed cryptantigens are significantly more sensitive to agglutination by certain lectins than by polyclonal antibodies. Peanut agglutinin (PNA), Polybrene, and Glycine max lectins are frequently used for the identification of different cryptantigens. The application of lectins as an anti-B reagent has proven to be as useful as human polyclonal or mouse monoclonal antibodies. Besides their specificity, lectins are excellent reagents because of their lower cost and indigenous production. The importance of various lectins used as markers for blood grouping is discussed.

  2. Lectin cDNA and transgenic plants derived therefrom

    Science.gov (United States)

    Raikhel, Natasha V.

    2000-10-03

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

  3. Research Progress and Perspectives of Nitrogen Fixing Bacterium, Gluconacetobacter diazotrophicus, in Monocot Plants

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    N. Eskin

    2014-01-01

    Full Text Available Gluconacetobacter diazotrophicus is a nitrogen fixing bacterium originally found in monocotyledon sugarcane plants in which the bacterium actively fixes atmosphere nitrogen and provides significant amounts of nitrogen to plants. This bacterium mainly colonizes intercellular spaces within the roots and stems of plants and does not require the formation of the complex root organ like nodule. The bacterium is less plant/crop specific and indeed G. diazotrophicus has been found in a number of unrelated plant species. Importantly, as the bacterium was of monocot plant origin, there exists a possibility that the nitrogen fixation feature of the bacterium may be used in many other monocot crops. This paper reviews and updates the research progress of G. diazotrophicus for the past 25 years but focuses on the recent research development.

  4. Lectin-like bacteriocins from Pseudomonas spp. utilise D-rhamnose containing lipopolysaccharide as a cellular receptor.

    Science.gov (United States)

    McCaughey, Laura C; Grinter, Rhys; 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

    2014-02-01

    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.

  5. Lectin-like bacteriocins from Pseudomonas spp. utilise D-rhamnose containing lipopolysaccharide as a cellular receptor.

    Directory of Open Access Journals (Sweden)

    Laura C McCaughey

    2014-02-01

    Full Text Available 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.

  6. Comparative analysis of ABCB1 reveals novel structural and functional conservation between monocots and dicots

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    Amandeep Kaur Dhaliwal

    2014-11-01

    Full Text Available Phytohormone auxin plays a critical role in modulating plant architecture by creating a gradient regulated via its transporters such as ATP-binding cassette (ABC B1. Except for Arabidopsis and maize, where it was shown to interrupt auxin transport, ABCB1’s presence, structure and function in crop species is not known. Here we describe the structural and putative functional organization of ABCB1 among monocots relative to that of dicots. Identified from various plant species following specific and stringent criteria, ZmABCB1’s ‘true’ orthologs sequence identity ranged from 56-90% at the DNA and 75-91% at the predicted amino acid (aa level. Relative to ZmABCB1, the size of genomic copies ranged from -27 to +1.5% and aa from -7.7 to +0.6%. With the average gene size being similar (5.8 kb in monocots and 5.7 kb in dicots, dicots have about triple the number of introns with an average size of 194 bp (total 1743 bp compared to 556 bp (total 1667 bp in monocots. The intron-exon junctions across species were however conserved. N-termini of the predicted proteins were highly variable: in monocots due to mismatches and small deletions of 1-13 aa compared to large, species-specific deletions of up to 77 aa in dicots. The species- family-, and group- specific conserved motifs were identified in the N-terminus and linker regions of protein, possibly responsible for the specific functions. The near-identical conserved motifs of Nucleotide Binding Domains (NBDs in two halves of the protein showed subtle aa changes possibly favoring ATP binding to the N-terminus. Predicted 3-D protein structures showed remarkable similarity with each other and for the residues involved in auxin binding.

  7. In tropical lowland rain forests monocots have tougher leaves than dicots, and include a new kind of tough leaf

    DEFF Research Database (Denmark)

    Dominy, N.J.; Grubb, P.J.; Jackson, R.V.

    2008-01-01

    -tolerant or gap-demanding species were considered. Conclusions: It is predicted that monocots will be found to experience lower rates of herbivory by invertebrates than dicots. The tough monocot leaves include both stiff leaves containing relatively little water at saturation (e.g. palms), and leaves which lack...... stiffness, are rich in water at saturation and roll readily during dry weather or even in bright sun around midday (e.g. gingers, heliconias and marants). Monocot leaves also show that it is possible for leaves to be notably tough throughout the expansion phase of development, something never recorded...... for dicots. The need to broaden the botanist's mental picture of a ‘tough leaf' is emphasized.   Key words: Dicots, fracture toughness, herbivory, leaves, monocots, punch strength, tropical rain forest  ...

  8. [Lectins of Dryopteris Adans fern species].

    Science.gov (United States)

    Basheka, O V; Stetsenko, N M; Pogorila, N F

    1999-01-01

    Lectin activity of three ferns species (Dryopteris bushiana Fom., D. laeta (Kom.) C. Chr, D. pseudomas (Wollaston) Holub et Pouzar) has been studied. We used hemagglutination reaction albumin and globulin fractions of fronds and rhizomes extracts with rat erythrocytes. The frond extract of D. pseudomas have shown higher activity as compared with other extracts. The lectin activity of D. laeta leaves was absent. The rhizomes of all three fern species could be characterized as high activity. Based on lectin activity the species were placed as follows order: D. buschiana > D. pseudomas > D. laeta. The dependence with lectin activity and elements (Mn, Fe, Cu, Ni, Zn, Pb, Rb, Sr) content were not found.

  9. Homology modelling of the core domain of the endogenous lectin comitin: structural basis for its mannose-binding specificity.

    Science.gov (United States)

    Barre, A; Van Damme, E J; Peumans, W J; Rougé, P

    1999-03-01

    The N-terminal core domain of comitin from the slime mold Dictyostelium discoideum has been modelled from the X-ray coordinates of the monocot mannose-binding lectin from snowdrop (Galanthus nivalis). Docking experiments performed on the three-dimensional model showed that two of the three mannose-binding sites of the comitin monomer are functional. They are located at both ends of the comitin dimer whereas the actin-interacting region occurs in the central hinge region where both monomers are non covalently associated. This distribution is fully consistent with the bifunctional character of comitin which is believed to link the Golgi vesicles exhibiting mannosylated membrane glycans to the actin cytoskeleton in the cell.

  10. Lectins in human cancer: both a devil and an angel?

    Science.gov (United States)

    Dan, Xiu Li; Ng, Tzi Bun

    2013-09-01

    Lectins are a group of proteins which could recognize different sugar structures and specifically initiate reversible binding with them. Lectins are universally expressed in different organisms and undertake important biological roles. Understanding of their inherent roles and mechanisms that they employ has inspired researches with new ideas and applications. For example, along with the revelation of their anti-insect function, plant lectins exhibit great potential in agriculture. In human beings, lectins shoulder great missions in cell communication, differentiation and vesicle trafficking etc., aberrant expression of lectins is always associated with diseases. Mannan-binding lectin deficiency leads to immune disorder and liver sinusoidal endothelial cell lectin is involved in colorectal carcinoma liver metastasis. In this review, we present two contradictory roles of lectins in human cancer: the promotive roles of homologous lectins and suppressive roles of heterologous lectins in cancer development. Hopefully, this review will facilitate a better understanding of tumorigenesis and provide references for cancer treatment.

  11. Similar genetic switch systems might integrate the floral inductive pathways in dicots and monocots

    DEFF Research Database (Denmark)

    Andersen, C.H.; Jensen, C.S.; Petersen, K.

    2004-01-01

    A recent paper by Million Tadege et A shows that a SOC1-like gene from rice, OsSOC1, can complement the Arabidopsis soc1 mutant, and that ectopic expression of the Arabidopsis floral repressor FLC in rice delays flowering and up-regulation of OsSOC1 These findings, together with the identificatio...... of the wheat vernalization VRN1 locus as an AP1 homologue, suggest that related genetic switch systems control floral transition in dicots and monocots but that they are based on different MADS-box transcription factors....

  12. The areas of application for plant lectins

    Directory of Open Access Journals (Sweden)

    Melnykova N. M.

    2013-09-01

    Full Text Available Lectins, in particular from plants, are proteins of non-immune origin that are able to bind carbohydrates with high specificity. Due to their properties, phytolectins are of great interest in practical applications. They were shown to play an important role in forming strategies for treatment of disease including cancer and HIV. Plant lectins are an important tool in glycomic studies. Plant lectins with fungicidal and insecticidal activities are used in transgenic technologies to increase plant resistance to pests and phytopathogens. The introduction of lectin-like kinases genes into plant genome was shown to be perspective way to protect plants against environmental stresses and regulate plant growth. Engineering of phytolectins allows obtaining molecules with known carbohydrate specificity that can be applied in various areas. The studies are underway with the aim of design of lectin-based drug delivery systems as well as the pharmaceutical drugs containing plant lectins. Because of the ability of phytolectins to bind to different substances they can be more widely used in the future. The review focuses on current data and future possibilities in the application of plant lectins.

  13. Agglutination of Helicobacter pylori coccoids by lectins

    Institute of Scientific and Technical Information of China (English)

    Mar Mar Khin; Jie Song Hua; Hah Cong Ng; Bow Ho; Torkel Wadstrorr

    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. Interestingly, heating of H.pylori cells at 60℃ for 1 hour 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 theevents 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.

  14. Anti-HIV Ⅰ/Ⅱ Activity and Molecular Cloning of a Novel Mannose/Sialic Acid-binding Lectin from Rhizome of Polygonatum cyrtonema Hua

    Institute of Scientific and Technical Information of China (English)

    Jie AN; Jin-Ku BAO; Jin-Zhi LIU; Chuan-Fang WU; Jian LI; Lei DAI; Els Van DAMME; Jan BALZARINI; Erik De CLERCQ; Fang CHEN

    2006-01-01

    The anti-human immunodeficiency virus (HIV) Ⅰ/Ⅱ activity of a mannose and sialic acid binding lectin isolated from rhizomes of Polygonatum cyrtonema Hua was elucidated by comparing its HIV infection inhibitory activity in MT-4 and CEM cells with that of other mannose-binding lectins (MBLs). The anti-HIV activity of Polygonatum cyrtonema Hua lectin (PCL) was 10- to 100-fold more potent than other tested MBLs, but without significant cytotoxicity towards MT-4 or CEM cells. To amplify cDNA of PCL by 3'/5'-rapid amplification of cDNA ends (RACE), the 30 amino acids of N-terminal were determined by sequencing and the degenerate oligonucleotide primers were designed. The full-length cDNA of PCL contained 693 bp with an open reading frame encoding a precursor protein of 160 amino acid residues, consisting of a 28-residue signal peptide, a 22-residue C-terminal cleavage peptide and a 110-residue mature polypeptide which contained three tandemly arranged subdomains with an obvious sequence homology to the monocot MBL. However, only one active mannose-binding site (QDNVY) was found in subdomain Ⅰ of PCL, that of subdomain Ⅱ and Ⅲ changed to HNNVY and PDNVY, respectively. There was no intron in PCL, which was in good agreement with other monocot MBLs. Molecular modeling of PCL indicated that its three-dimen-sional structure resembles that of the snowdrop agglutinin. By docking, an active sialic acid-binding site was found in PCL. The instabilization of translation initiation region (TIR) in mRNA of PCL benefits its high expression in rhizomes.

  15. Assessing biosafety of GM plants containing lectins

    DEFF Research Database (Denmark)

    Poulsen, Morten; Pedersen, Jan W.

    2010-01-01

    of the lectins that are potentially useful for insect resistance will pose no health risk in genetically modified (GM) plants. Since some lectins are known for their toxicity to humans, the insertion of lectin genes in food crop plants will have to be assessed carefully. It is expected that in some cases...... there will be a need to perform animal tests of such GM plants in order to eliminate any uncertainties about potential safety issues for these plants. A 90-day study designed and optimized for this purpose is suggested as one way to cope with these uncertainties....

  16. Chromosome studies in the aquatic monocots of Myanmar: A brief review with additional records

    Directory of Open Access Journals (Sweden)

    Yu Ito

    2014-05-01

    Full Text Available Myanmar (Burma constitutes a significant component of the Indo-Myanmar biodiversity hotspot, with elements of the Indian, the Indochina, and the Sino-Japanese floristic regions, yet thus far only a few reliable sources of the country's flora have been available. As a part of a contribution for the floristic inventory of Myanmar, since it is important in a floristic survey to obtain as much information as possible, in addition to previous two reports, here we present three more chromosome counts in the aquatic monocots of Myanmar: Limnocharis flava with 2n = 20, Sagittaria trifolia with 2n = 22 (Alismataceae, and Potamogeton distinctus × P. nodosus with 2n = 52 (Potamogetonaceae; the third one is new to science. A brief review of cytological researches in the floristic regions' 45 non-hybrid aquatic monocots plus well investigated two inter-specific hybrids that are recorded in Myanmar is given, indicating that the further works with a focus on species in Myanmar that has infra-specific chromosome variation in the floristic regions will address the precise evolutionary history of the aquatic flora of Myanmar.

  17. Chromosome studies in the aquatic monocots of Myanmar: A brief review with additional records.

    Science.gov (United States)

    Ito, Yu; Tanaka, Nobuyuki

    2014-01-01

    Myanmar (Burma) constitutes a significant component of the Indo-Myanmar biodiversity hotspot, with elements of the Indian, the Indochina, and the Sino-Japanese floristic regions, yet thus far only a few reliable sources of the country's flora have been available. As a part of a contribution for the floristic inventory of Myanmar, since it is important in a floristic survey to obtain as much information as possible, in addition to previous two reports, here we present three more chromosome counts in the aquatic monocots of Myanmar: Limnocharisflava with 2n = 20, Sagittariatrifolia with 2n = 22 (Alismataceae), and Potamogetondistinctus × Potamogetonnodosus with 2n = 52 (Potamogetonaceae); the third one is new to science. A brief review of cytological researches in the floristic regions' 45 non-hybrid aquatic monocots plus well investigated two inter-specific hybrids that are recorded in Myanmar is given, indicating that the further works with a focus on species in Myanmar that has infra-specific chromosome variation in the floristic regions will address the precise evolutionary history of the aquatic flora of Myanmar.

  18. KNOX1 genes regulate lignin deposition and composition in monocots and dicots.

    Directory of Open Access Journals (Sweden)

    Brad T Townsley

    2013-05-01

    Full Text Available Plant secondary cell walls are deposited mostly in vascular tissues such as xylem vessels, tracheids, and fibers. These cell walls are composed of a complex matrix of compounds including cellulose, hemicellulose, and lignin. Lignin functions primarily to maintain the structural and mechanical integrity of both the transport vessel and the entire plant itself. Since lignin has been identified as a major source of biomass for biofuels, regulation of secondary cell wall biosynthesis has been a topic of much recent investigation. Biosynthesis and patterning of lignin involves many developmental and environmental cues including evolutionarily conserved transcriptional regulatory modules and hormonal signals. Here, we investigate the role of the class I KNOX genes and gibberellic acid in the lignin biosynthetic pathway in a representative monocot and a representative eudicot. Knotted1 overexpressing mutant plants showed a reduction in lignin content in both maize and tobacco. Expression of four key lignin biosynthesis genes was analyzed and revealed that KNOX1 genes regulate at least two steps in the lignin biosynthesis pathway. The negative regulation of lignin both in a monocot and a eudicot by the maize Kn1 gene suggests that lignin biosynthesis may be preserved across large phylogenetic distances. The evolutionary implications of regulation of lignification across divergent species are discussed.

  19. Diversification of the RAB Guanosine Triphosphatase Family in Dicots and Monocots

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    RAB guanosine triphosphatases (GTPases) are key regulators of vesicle trafficking and are essential to the growth and development of all eukaryotic cells. During evolution, the RAB family has expanded in different patterns to facilitate distinct cellular, developmental and physiological adaptations. Yeast has only 11 family members, whereas mammalian RABs have expanded to 18 RAB subfamilies. Plant RABs have diversified primarily by duplicating members within a single subfamily. Plant RABs are divided into eight subfamilies, corresponding to mammalian RAB1, RAB2, RAB5, RAB6,RAB7, RAB8, RAB11 and RAB18. Functional diversification of these is exemplified by the RAB11s, orthologs of which are partitioned into unique cell compartments in plants where they function to transport vesicles during localized tip growth.Similarly, the RAB2 family in grasses is likely involved in vesicle secretion associated with wall expansion, as determined by analysis of over-expression mutants. We propose that dicots and monocots have also diverged in their RAB profiles to accommodate unique cellular functions between the two groups. Here we present a bioinformatics analysis comparing the RAB sub-families of rice, maize and Arabidopsis. These results will guide future functional studies to test for the role of diversification of subfamilies unique to monocots compared to dicots.

  20. Enhanced Agrobacterium-mediated transformation efficiencies in monocot cells is associated with attenuated defense responses.

    Science.gov (United States)

    Zhang, Wan-Jun; Dewey, Ralph E; Boss, Wendy; Phillippy, Brian Q; Qu, Rongda

    2013-02-01

    Plant defense responses can lead to altered metabolism and even cell death at the sites of Agrobacterium infection, and thus lower transformation frequencies. In this report, we demonstrate that the utilization of culture conditions associated with an attenuation of defense responses in monocot plant cells led to highly improved Agrobacterium-mediated transformation efficiencies in perennial ryegrass (Lolium perenne L.). The removal of myo-inositol from the callus culture media in combination with a cold shock pretreatment and the addition of L-Gln prior to and during Agrobacterium-infection resulted in about 84 % of the treated calluses being stably transformed. The omission of myo-inositol from the callus culture media was associated with the failure of certain pathogenesis related genes to be induced after Agrobacterium infection. The addition of a cold shock and supplemental Gln appeared to have synergistic effects on infection and transformation efficiencies. Nearly 60 % of the stably transformed calluses regenerated into green plantlets. Calluses cultured on media lacking myo-inositol also displayed profound physiological and biochemical changes compared to ones cultured on standard growth media, such as reduced lignin within the cell walls, increased starch and inositol hexaphosphate accumulation, enhanced Agrobacterium binding to the cell surface, and less H(2)O(2) production after Agrobacterium infection. Furthermore, the cold treatment greatly reduced callus browning after infection. The simple modifications described in this report may have broad application for improving genetic transformation of recalcitrant monocot species.

  1. Monocot leaves are eaten less than dicot leaves in tropical lowland rain forests: correlations with toughness and leaf presentation

    DEFF Research Database (Denmark)

    Grubb, P.J.; Jackson, R.V.; Barberis, I.M.

    2008-01-01

    : At six sites on four continents, estimates were made of lamina area loss from the four most recently mature leaves of focal monocots and of the nearest dicot shoot. Measurements of leaf mass per unit area, and the concentrations of water and nitrogen were made for many of the species. In Panama...... of leaf mass per unit area, or concentrations of water or nitrogen. At only one site was the increase in loss from first to fourth mature leaf significant (also large and the same in monocots and dicots), but the losses sustained during expansion were much smaller in the monocots. In the leaf-cutter ant...... insects in tropical lowland rain forest, and that the relative importance varies widely with species. The difficulties of establishing unequivocally the roles of leaf toughness and leaf folding or rolling in a given case are discussed. Key words: anti-herbivore defences, dicots, herbivory, leaf folding...

  2. Lectin binding in normal donkey eyeball

    Directory of Open Access Journals (Sweden)

    Khaled Aly

    2013-10-01

    Full Text Available In the present study, the distribution of various sugar residues in the eyeball tissues of sexually mature donkey was examined by employing fluorescein isothiocyanate-conjugated lectins. Our results revealed the presence of mannose (labeled by lectins ConA, galactose (labeled by PNA, GSAI, ECA, GalNAc (labeled by SBA, VVA, and GlcNAc (labeled by WGA residues in the donkey ocular tissues. The epithelium and stroma of the ocular tissues were labeled with mannose (ConA and GlcNAc (WGA binding lectins. Binding sites for WGA and PNA to the rod and cone cells of the retina were evident. The lectins Con A, WGA and GSAI are bound strongly to the endothelium of blood vessels and to smooth muscle cells of the iris. In conclusion, the findings of the present study clearly indicate that the donkey eyeball contains a wide range of glycoconjugates (bearing mannosyl, galactosyl and glucosly residues, and it lacks fucosyl residues.

  3. Legume Lectins: Proteins with Diverse Applications

    Science.gov (United States)

    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

  4. Lectin Complement Pathway Proteins in Healthy Individuals

    DEFF Research Database (Denmark)

    Troldborg, Anne; Hansen, Annette; Hansen, Søren W K

    2017-01-01

    Since the discovery of the lectin pathway of complement activation, numerous clinical cohorts have been examined for one or more of the proteins, with the intention of uncovering the functions of the proteins or with the aim of discovering new biomarkers or diagnostic tools. To unveil the abnormal......, it is pivotal to know the normal. Our aim was to describe the concentrations of the eleven known proteins of the lectin pathway in serum and plasma and to uncover possible gender differences, age and diurnal variations, which must be taken into account for investigations in different cohorts. We examined...... the concentrations of all lectin pathway proteins (mannan-binding lectin (MBL), H-ficolin, L-ficolin, M-ficolin, collectin-K1, collectin-L1, MBL-associated serine protease 2 (MASP-2), MASP-3, MBL associated protein of 44 kDa (MAp44) and MAp19 in 300 Danish blood donors in serum and EDTA plasma in established assays...

  5. Lectin interactions with alpha-galactosylated xenoantigens

    DEFF Research Database (Denmark)

    Kirkeby, Svend; Moe, Dennis

    2002-01-01

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

  6. Purification of a Lectin from Arisaema erubescens (Wall. Schott and Its Pro-Inflammatory Effects

    Directory of Open Access Journals (Sweden)

    Run Jun Shi

    2011-11-01

    Full Text Available The monocot lectin from the tubers of Arisaema erubescens (Wall. Schott has been purified by consecutive hydrophobic chromatography and ion exchange chromatography methods. The molecular weight of this A. erubescens lectin (AEL was determined to be about 12 kDa by high performance liquid chromatography (HPLC and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE methods. AEL could agglutinate rabbit erythrocytes. The haemagglutination activity of AEL was only inhibited by asialofetuin, while monosaccharide did not react. Rat paw edema and neutrophil migration models were used to investigate the pro-inflammatory activity of AEL. AEL (100 and 200 μg/paw could induce significant rat paw edema. In addition, AEL (100, 200 and 300 μg/mL/cavity could induce significant and dose-dependent neutrophil migration in the rat peritoneal cavities. Besides, AEL at doses ranging from 100 to 300 μg/mL/cavity could significantly increase the concentration of nitric oxide (NO, prostaglandin E2 (PGE2 and tumor necrosis factor alpha (TNF-α in peritoneal fluid. As compared with control animals, 75% depletion in the number of resident cells following peritoneal lavage did not reduce the AEL-induced neutrophil migration. However, pre-treatment with 3% thioglycollate which increased the peritoneal macrophage population by 201%, enhanced the neutrophil migration induced by AEL (200 μg/mL/cavity (p < 0.05. Reduction of peritoneal mast cell population by chronic treatment of rat peritoneal cavities with compound 48/80 (N-methyl-p-methoxyphenethylamine with formaldehyde did not modify AEL-induced neutrophil migration. The results provided the basis for identifying the toxic components of A. erubescens and AEL could be a new useful tool for pro-inflammatory research.

  7. Conserved Subgroups and Developmental Regulation in the Monocot rop Gene Family1[w

    Science.gov (United States)

    Christensen, Todd M.; Vejlupkova, Zuzana; Sharma, Yogesh K.; Arthur, Kirstin M.; Spatafora, Joseph W.; Albright, Carol A.; Meeley, Robert B.; Duvick, Jon P.; Quatrano, Ralph S.; Fowler, John E.

    2003-01-01

    Rop small GTPases are plant-specific signaling proteins with roles in pollen and vegetative cell growth, abscisic acid signal transduction, stress responses, and pathogen resistance. We have characterized the rop family in the monocots maize (Zea mays) and rice (Oryza sativa). The maize genome contains at least nine expressed rops, and the fully sequenced rice genome has seven. Based on phylogenetic analyses of all available Rops, the family can be subdivided into four groups that predate the divergence of monocots and dicots; at least three have been maintained in both lineages. However, the Rop family has evolved differently in the two lineages, with each exhibiting apparent expansion in different groups. These analyses, together with genetic mapping and identification of conserved non-coding sequences, predict orthology for specific rice and maize rops. We also identified consensus protein sequence elements specific to each Rop group. A survey of ROP-mRNA expression in maize, based on multiplex reverse transcriptase-polymerase chain reaction and a massively parallel signature sequencing database, showed significant spatial and temporal overlap of the nine transcripts, with high levels of all nine in tissues in which cells are actively dividing and expanding. However, only a subset of rops was highly expressed in mature leaves and pollen. Intriguingly, the grouping of maize rops based on hierarchical clustering of expression profiles was remarkably similar to that obtained by phylogenetic analysis. We hypothesize that the Rop groups represent classes with distinct functions, which are specified by the unique protein sequence elements in each group and by their distinct expression patterns. PMID:14605221

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

    Science.gov (United States)

    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.

  9. Lectin affinity chromatography of glycolipids

    Energy Technology Data Exchange (ETDEWEB)

    Torres, B.V.; Smith, D.F.

    1987-05-01

    Since glycolipids (GLs) are either insoluble or form mixed micelles in water, lectin affinity chromatography in aqueous systems has not been applied to their separation. They have overcome this problem by using tetrahydrofuran (THF) in the mobile phase during chromatography. Affinity columns prepared with the GalNAc-specific Helix pomatia agglutinin (HPA) and equilibrated in THF specifically bind the (/sup 3/H)oligosaccharide derived from Forssman GL indicating that the immobilized HPA retained its carbohydrate-binding specificity in this solvent. Intact Forssman GL was bound by the HPA-column equilibrated in THF and was specifically eluted with 0.1 mg/ml GalNAc in THF. Purification of the Forssman GL was achieved when a crude lipid extract of sheep erythrocyte membranes was applied to the HPA-column in THF. Non-specifically bound GLs were eluted from the column using a step gradient of aqueous buffer in THF, while the addition of GalNAc was required to elute the specifically bound GLs. Using this procedure the A-active GLs were purified from a crude lipid extract of type A human erythrocytes in a single chromatographic step. The use of solvents that maintain carbohydrate-binding specificity and lipid solubility will permit the application of affinity chromatography on immobilized carbohydrate-binding proteins to intact GLs.

  10. Diversity of lectins in Macrobrachium rosenbergii and their expression patterns under spiroplasma MR-1008 stimulation.

    Science.gov (United States)

    Zhu, Huanxi; Du, Jie; Hui, Kai-Min; Liu, Peng; Chen, Jing; Xiu, Yunji; Yao, Wei; Wu, Ting; Meng, Qingguo; Gu, Wei; Ren, Qian; Wang, Wen

    2013-08-01

    Lectins play important roles in crustacean innate immunity through recognition of foreign pathogens. In this study, 20 lectins including C-type lectins [dual-carbohydrate recognition domain (CRD) type and single-CRD type], L-type lectin, and lectin with low-density lipoprotein class A (LDLa) domain were identified from the freshwater prawn Macrobrachium rosenbergii. The tissue distribution and expression patterns of these lectins under spiroplasma strain MR-1008 challenge were investigated. Most of the lectins were found to be mainly distributed in the hepatopancreas. Lectin5, Lectin14, Lectin17, and Lectin18 exhibited the highest expression level in the hemocytes, nerve, intestine, and heart, respectively. MrLec1 to MrLec6 (dual-CRD lectins) in the hepatopancreas were up-regulated by spiroplasma challenge. Single-CRD lectins reached the highest level at 72 h after spiroplasma challenge. Lectin9 and Lectin15 both belong to L-type lectins. At post-spiroplasma challenge, Lectin9 expression was up-regulated, whereas Lectin15 expression was down-regulated. Lectin11 with LDLa domain showed the highest level after 12 h Lectin18 and Lectin20, namely, CD209, were also up-regulated by spiroplasma challenge. Lectin14, a C-type lectin, quickly reached the highest level after 2 h Lectin16 showed the highest level after 72 h Lectin5 reached the highest level in cultured hemocytes after 6 h Lectin17 in the intestine and Lectin14 in the nerve were slightly up-regulated after 6 and 2 h, respectively. Our research results indicate that lectins may play important roles in early or late immune responses against spiroplasma challenge.

  11. Insights into carbohydrate recognition by Narcissus pseudonarcissus lectin: the crystal structure at 2 A resolution in complex with alpha1-3 mannobiose.

    Science.gov (United States)

    Sauerborn, M K; Wright, L M; Reynolds, C D; Grossmann, J G; Rizkallah, P J

    1999-07-01

    Carbohydrate recognition by monocot mannose-binding lectins was studied via the crystal structure determination of daffodil (Narcissus pseudonarcissus) lectin. The lectin was extracted from daffodil bulbs, and crystallised in the presence of alpha-1,3 mannobiose. Molecular replacement methods were used to solve the structure using the partially refined model of Hippeastrum hybrid agglutinin as a search model. The structure was refined at 2.0 A resolution to a final R -factor of 18.7 %, and Rfreeof 26.7 %. The main feature of the daffodil lectin structure is the presence of three fully occupied binding pockets per monomer, arranged around the faces of a triangular beta-prism motif. The pockets have identical topology, and can bind mono-, di- or oligosaccharides. Strand exchange forms tightly bound dimers, and higher aggregation states are achieved through hydrophobic patches on the surface, completing a tetramer with internal 222-symmetry. There are therefore 12 fully occupied binding pockets per tetrameric cluster. The tetramer persists in solution, as shown with small-angle X-ray solution scattering. Extensive sideways and out-of-plane interactions between tetramers, some mediated via the ligand, make up the bulk of the lattice contacts.A fourth binding site was also observed. This is unique and has not been observed in similar structures. The site is only partially occupied by a ligand molecule due to the much lower binding affinity. A comparison with the Galanthus nivalis agglutinin/mannopentaose complex suggests an involvement of this site in the recognition mechanism for naturally occurring glycans.

  12. Rapid identification of Mycobacterium species by lectin agglutination.

    Science.gov (United States)

    Athamna, Abed; Cohen, Dani; Athamna, Muhammad; Ofek, Itzhak; Stavri, Henriette

    2006-05-01

    The purpose of the present study is to explore the possibility that plant lectins can be used for the development of rapid and inexpensive technique for differentiation of mycobacterial species. The method is based on interaction between mycobacteria and lectins as visualized by agglutination in a microtiter plate. We employed 18 mycobacterium species and determined the minimal lectin concentration (MLC) of 23 different lectins. For some of the bacteria as a high as 1000 microg/ml of one or more lectins were required to induce agglutination, while for other strains as low as 1.95 microg/ml of the lectin were needed. A unique pattern of agglutination was observed for each species over a range of 62-1000 microg/ml lectin concentrations. There were little or no variations in MLC within strains (intraspecies) of each of two species tested. In contrast, there were marked interspecies variations in MLC. Analysis of the MLC showed that the highest score of interspecies differences with 23 lectins was obtained at 125 microg/ml lectin concentration. At this concentration it was found that the pattern of agglutinations with only two lectins was sufficient to differentiate mycobacterium species from each other. Because the bacteria-lectin interaction is adaptable to various methods of visualization, our findings may set the stage for developing a rapid and reliable tool to differentiate mycobacterium species.

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

    Directory of Open Access Journals (Sweden)

    Mohamed Ali Abol Hassan

    2015-04-01

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

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

    Directory of Open Access Journals (Sweden)

    Karpiuk UV

    2013-03-01

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

  15. Animal lectins: potential receptors for ginseng polysaccharides

    Directory of Open Access Journals (Sweden)

    So Hee Loh

    2017-01-01

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

  16. Mechanisms underlying the long-term survival of the monocot Dracaena marginata under drought conditions.

    Science.gov (United States)

    Jupa, Radek; Plichta, Roman; Paschová, Zuzana; Nadezhdina, Nadezhda; Gebauer, Roman

    2017-09-01

    Efficient water management is essential for the survival of vascular plants under drought stress. While interrelations among drought stress, plant anatomy and physiological functions have been described in woody dicots, similar research is very limited for non-palm arborescent and shrubby monocots despite their generally high drought tolerance. In this study, potted transplants of Dracaena marginata Lam. in primary growth stage were exposed to several short- and long-term drought periods. Continuous measurements of sap flow and stem diameter, the evaluation of capacitance and leaf conductance, the quantification of non-structural carbohydrates (NSC), and organ-specific anatomical analyses were performed to reveal the mechanisms promoting plant resistance to limited soil moisture. The plants showed sensitive stomata regulation in the face of drying soil, but only intermediate resistance to water loss through cuticular transpiration. The water losses were compensated by water release from stem characterized by densely interconnected, parenchyma-rich ground tissue and considerable hydraulic capacitance. Our results suggest that the high concentration of osmotically active NSC in aboveground organs combined with the production of root pressures supported water uptake and the restoration of depleted reserves after watering. The described anatomical features and physiological mechanisms impart D. marginata with high resistance to irregular watering and long-term water scarcity. These findings should help to improve predictions with respect to the impacts of droughts on this plant group. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Lower Miocene plant assemblage with coastal-marsh herbaceous monocots from the Vienna Basin (Slovakia)

    Science.gov (United States)

    Kvaček, Zlatko; Teodoridis, Vasilis; Kováčová, Marianna; Schlögl, Ján; Sitár, Viliam

    2014-06-01

    A new plant assemblage of Cerová-Lieskové from Lower Miocene (Karpatian) deposits in the Vienna Basin (western Slovakia) is preserved in a relatively deep, upper-slope marine environment. Depositional conditions with high sedimentation rates allowed exceptional preservation of plant remains. The plant assemblage consists of (1) conifers represented by foliage of Pinus hepios and Tetraclinis salicornioides, a seed cone of Pinus cf. ornata, and by pollen of the Cupressaceae, Pinaceae, Pinus sp. and Cathaya sp., and (2) angiosperms represented by Cinnamomum polymorphum, Platanus neptuni, Potamogeton sp. and lauroid foliage, by pollen of Liquidambar sp., Engelhardia sp. and Craigia sp., and in particular by infructescences (so far interpreted as belonging to cereal ears). We validate genus and species assignments of the infructescences: they belong to Palaeotriticum Sitár, including P. mockii Sitár and P. carpaticum Sitár, and probably represent herbaceous monocots that inhabited coastal marshes, similar to the living grass Spartina. Similar infructescences occur in the Lower and Middle Miocene deposits of the Carpathian Foredeep (Slup in Moravia), Tunjice Hills (Žale in Slovenia), and probably also in the Swiss Molasse (Lausanne). This plant assemblage demonstrates that the paleovegetation was represented by evergreen woodland with pines and grasses in undergrowth, similar to vegetation inhabiting coastal brackish marshes today. It also indicates subtropical climatic conditions in the Vienna Basin (central Paratethys), similar to those implied by other coeval plant assemblages from Central Europe

  18. CRISPR/Cas9-Based Multiplex Genome Editing in Monocot and Dicot Plants.

    Science.gov (United States)

    Ma, Xingliang; Liu, Yao-Guang

    2016-07-01

    The clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-mediated genome targeting system has been applied to a variety of organisms, including plants. Compared to other genome-targeting technologies such as zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs), the CRISPR/Cas9 system is easier to use and has much higher editing efficiency. In addition, multiple "single guide RNAs" (sgRNAs) with different target sequences can be designed to direct the Cas9 protein to multiple genomic sites for simultaneous multiplex editing. Here, we present a procedure for highly efficient multiplex genome targeting in monocot and dicot plants using a versatile and robust CRISPR/Cas9 vector system, emphasizing the construction of binary constructs with multiple sgRNA expression cassettes in one round of cloning using Golden Gate ligation. We also describe the genotyping of targeted mutations in transgenic plants by direct Sanger sequencing followed by decoding of superimposed sequencing chromatograms containing biallelic or heterozygous mutations using the Web-based tool DSDecode. © 2016 by John Wiley & Sons, Inc.

  19. Lower Miocene plant assemblage with coastal-marsh herbaceous monocots from the Vienna Basin (Slovakia

    Directory of Open Access Journals (Sweden)

    Kvaček Zlatko

    2014-06-01

    Full Text Available A new plant assemblage of Cerová-Lieskové from Lower Miocene (Karpatian deposits in the Vienna Basin (western Slovakia is preserved in a relatively deep, upper-slope marine environment. Depositional conditions with high sedimentation rates allowed exceptional preservation of plant remains. The plant assemblage consists of (1 conifers represented by foliage of Pinus hepios and Tetraclinis salicornioides, a seed cone of Pinus cf. ornata, and by pollen of the Cupressaceae, Pinaceae, Pinus sp. and Cathaya sp., and (2 angiosperms represented by Cinnamomum polymorphum, Platanus neptuni, Potamogeton sp. and lauroid foliage, by pollen of Liquidambar sp., Engelhardia sp. and Craigia sp., and in particular by infructescences (so far interpreted as belonging to cereal ears. We validate genus and species assignments of the infructescences: they belong to Palaeotriticum Sitár, including P. mockii Sitár and P. carpaticum Sitár, and probably represent herbaceous monocots that inhabited coastal marshes, similar to the living grass Spartina. Similar infructescences occur in the Lower and Middle Miocene deposits of the Carpathian Foredeep (Slup in Moravia, Tunjice Hills (Žale in Slovenia, and probably also in the Swiss Molasse (Lausanne. This plant assemblage demonstrates that the paleovegetation was represented by evergreen woodland with pines and grasses in undergrowth, similar to vegetation inhabiting coastal brackish marshes today. It also indicates subtropical climatic conditions in the Vienna Basin (central Paratethys, similar to those implied by other coeval plant assemblages from Central Europe

  20. Functional conservation of the meiotic genes SDS and RCK in male meiosis in the monocot rice

    Institute of Scientific and Technical Information of China (English)

    Ling Chang; Hong Ma; Hong-Wei Xue

    2009-01-01

    The Arabidopsis SDS (SOLO DANCERS) and RCK (ROCK-N-ROLLERS) genes are important for male meiosis, but it is still unknown whether they represent conserved functions in plants. We have performed phylogenetic analy-ses of SDS and RCK and their respective homologs, and identified their putative orthologs in poplar and rice. Quan-titative real-time RT-PCR analysis indicated that rice SDS and RCK are expressed preferentially in young flowers, and transgenic RNAi rice lines with reduced expression of these genes exhibited normal vegetative development, but showed significantly reduced fertility with partially sterile flowers and defective pollens. SDS deficiency also caused a decrease in pollen amounts. Further cytological examination of male meiocytes revealed that the SDS deficiency led to defects in homolog interaction and bivalent formation in meiotic prophase I, and RCK deficiency resulted in defec-tive meiotic crossover formation. These results indicate that rice SDS and RCK genes have similar functions to their Arabidopsis orthologs. Because rice and Arabidopsis, respectively, are members of monocots and eudicots, two largest groups of flowering plants, our results suggest that the functions of SDS and RCK are likely conserved in flowering plants.

  1. Rice Brittleness Mutants: A Way to Open the 'Black Box' of Monocot Cell Wall Biosynthesis

    Institute of Scientific and Technical Information of China (English)

    Baocai Zhang; Yihua Zhou

    2011-01-01

    Rice is a model organism for studying the mechanism of cell wall biosynthesis and remolding in Gramineae.Mechanical strength is an important agronomy trait of rice(Oryza sativa L.)plants that affects crop lodging and grain yield.As a prominent physical property of cell walls,mechanical strength reflects upon the structure of different wall polymers and how they interact.Studies on the mechanisms that regulate the mechanical strength therefore consequently results in uncovering the genes functioning in cell wall biosynthesis and remodeling.Our group focuses on the study of isolation of brittle culm(bc)mutants and characterization of their corresponding genes.To date,several bc mutants have been reported.The identified genes have covered several pathways of cell wall biosynthesis,revealing many secrets of monocot cell wall biosynthesis.Here,we review the progress achieved in this research field and also highlight the perspectives in expectancy.All of those lend new insights into mechanisms of cell wall formation and are helpful for harnessing the waste rice straws for biofuel production.

  2. Systematic Comparisons of Orthologous Selenocysteine Methyltransferase and Homocysteine Methyltransferase Genes from Seven Monocots Species

    Directory of Open Access Journals (Sweden)

    De-yong ZHAO

    2015-06-01

    Full Text Available Identifying and manipulating genes underlying selenium metabolism could be helpful for increasing selenium content in crop grain, which is an important way to overcome diseases resulted from selenium deficiency. A reciprocal smallest distance algorithm (RSD approach was applied using two experimentally confirmed Homocysteine S-Methyltransferases genes (HMT1 and HMT2 and a putative Selenocysteine Methyltransferase (SMT from dicots plant Arabidopsis thaliana, to explore their orthologs in seven sequenced diploid monocot species: Oryza sativa, Zea mays, Sorghum bicolor, Brachypodium distachyon, Hordeum vulgare, Aegilops tauschii (the D-genome donor of common wheat and Triticum urartu (the A-genome donor of common wheat. HMT1 was apparently diverged from HMT2 and most of SMT orthologs were the same with that of HMT2 in this study, leading to the hypothesis that SMT and HMT originate from one common ancestor gene. Identifying orthologs provide candidates for further experimental confirmation; also it could be helpful in designing primers to clone SMT or HMT orthologs in other crops.

  3. Contractile roots in succulent monocots: convergence, divergence and adaptation to limited rainfall.

    Science.gov (United States)

    North, Gretchen B; Brinton, Erin K; Garrett, Tadao Y

    2008-08-01

    Contractile roots (CRs) that pull shoots further down in the soil are a possible example of convergent evolution in two monocot families, the Agavaceae and the Asphodelaceae. The association between CRs, water uptake and habitat aridity was investigated for agaves, yuccas and aloes by assessing the occurrence of CRs and the amount of root contraction for glasshouse-grown plants with respect to mean annual rainfall of their native habitats. Structural features of CRs as well as root hydraulic conductance were compared with those of non-contractile roots (NCRs). CRs occurred in 55% of the 73 species examined, including 64% of the agaves and 85% of the yuccas, but in none of the aloes despite the occurrence of CRs in related genera. The phylogenetic distribution of CRs was consistent with multiple acquisitions or losses of the trait. The amount of root contraction showed a highly significant negative relationship with mean annual rainfall, although other environmental factors may also be important. Radial hydraulic conductance of the basal (contractile) zone exceeded that of the midroot zone for CRs; for NCRs, the opposite was true. Thus, CRs in the species examined may provide a mechanism for greater water uptake near the soil surface in regions with limited rainfall.

  4. BAD-lectins: boronic acid-decorated lectins with enhanced binding affinity for the selective enrichment of glycoproteins.

    Science.gov (United States)

    Lu, Ying-Wei; Chien, Chih-Wei; Lin, Po-Chiao; Huang, Li-De; Chen, Chang-Yang; Wu, Sz-Wei; Han, Chia-Li; Khoo, Kay-Hooi; Lin, Chun-Cheng; Chen, Yu-Ju

    2013-09-03

    The weak and variable binding affinities exhibited by lectin-carbohydrate interactions have often compromised the practical utility of lectin in capturing glycoproteins for glycoproteomic applications. We report here the development and applications of a new type of hybrid biomaterial, namely a boronic acid-decorated lectin (BAD-lectin), for efficient bifunctional glycoprotein labeling and enrichment. Our binding studies showed an enhanced affinity by BAD-lectin, likely to be mediated via the formation of boronate ester linkages between the lectin and glycan subsequent to the initial recognition process and thus preserving its glycan-specificity. Moreover, when attached to magnetic nanoparticles (BAD-lectin@MNPs), 2 to 60-fold improvement on detection sensitivity and enrichment efficiency for specific glycoproteins was observed over the independent use of either lectin or BA. Tested at the level of whole cell lysates for glycoproteomic applications, three different types of BAD-lectin@MNPs exhibited excellent specificities with only 6% overlapping among the 295 N-linked glycopeptides identified. As many as 236 N-linked glycopeptides (80%) were uniquely identified by one of the BAD-lectin@MNPs. These results indicated that the enhanced glycan-selective recognition and binding affinity of BAD-lectin@MNPs will facilitate a complementary identification of the under-explored glycoproteome.

  5. Structural Comparison, Substrate Specificity, and Inhibitor Binding of AGPase Small Subunit from Monocot and Dicot: Present Insight and Future Potential

    Directory of Open Access Journals (Sweden)

    Kishore Sarma

    2014-01-01

    Full Text Available ADP-glucose pyrophosphorylase (AGPase is the first rate limiting enzyme of starch biosynthesis pathway and has been exploited as the target for greater starch yield in several plants. The structure-function analysis and substrate binding specificity of AGPase have provided enormous potential for understanding the role of specific amino acid or motifs responsible for allosteric regulation and catalytic mechanisms, which facilitate the engineering of AGPases. We report the three-dimensional structure, substrate, and inhibitor binding specificity of AGPase small subunit from different monocot and dicot crop plants. Both monocot and dicot subunits were found to exploit similar interactions with the substrate and inhibitor molecule as in the case of their closest homologue potato tuber AGPase small subunit. Comparative sequence and structural analysis followed by molecular docking and electrostatic surface potential analysis reveal that rearrangements of secondary structure elements, substrate, and inhibitor binding residues are strongly conserved and follow common folding pattern and orientation within monocot and dicot displaying a similar mode of allosteric regulation and catalytic mechanism. The results from this study along with site-directed mutagenesis complemented by molecular dynamics simulation will shed more light on increasing the starch content of crop plants to ensure the food security worldwide.

  6. Genomic analysis of NAC transcription factors in banana (Musa acuminata) and definition of NAC orthologous groups for monocots and dicots.

    Science.gov (United States)

    Cenci, Albero; Guignon, Valentin; Roux, Nicolas; Rouard, Mathieu

    2014-05-01

    Identifying the molecular mechanisms underlying tolerance to abiotic stresses is important in crop breeding. A comprehensive understanding of the gene families associated with drought tolerance is therefore highly relevant. NAC transcription factors form a large plant-specific gene family involved in the regulation of tissue development and responses to biotic and abiotic stresses. The main goal of this study was to set up a framework of orthologous groups determined by an expert sequence comparison of NAC genes from both monocots and dicots. In order to clarify the orthologous relationships among NAC genes of different species, we performed an in-depth comparative study of four divergent taxa, in dicots and monocots, whose genomes have already been completely sequenced: Arabidopsis thaliana, Vitis vinifera, Musa acuminata and Oryza sativa. Due to independent evolution, NAC copy number is highly variable in these plant genomes. Based on an expert NAC sequence comparison, we propose forty orthologous groups of NAC sequences that were probably derived from an ancestor gene present in the most recent common ancestor of dicots and monocots. These orthologous groups provide a curated resource for large-scale protein sequence annotation of NAC transcription factors. The established orthology relationships also provide a useful reference for NAC function studies in newly sequenced genomes such as M. acuminata and other plant species.

  7. sparse inflorescence1 encodes a monocot-specific YUCCA-like gene required for vegetative and reproductive development in maize.

    Science.gov (United States)

    Gallavotti, Andrea; Barazesh, Solmaz; Malcomber, Simon; Hall, Darren; Jackson, David; Schmidt, Robert J; McSteen, Paula

    2008-09-30

    The plant growth hormone auxin plays a critical role in the initiation of lateral organs and meristems. Here, we identify and characterize a mutant, sparse inflorescence1 (spi1), which has defects in the initiation of axillary meristems and lateral organs during vegetative and inflorescence development in maize. Positional cloning shows that spi1 encodes a flavin monooxygenase similar to the YUCCA (YUC) genes of Arabidopsis, which are involved in local auxin biosynthesis in various plant tissues. In Arabidopsis, loss of function of single members of the YUC family has no obvious effect, but in maize the mutation of a single yuc locus causes severe developmental defects. Phylogenetic analysis of the different members of the YUC family in moss, monocot, and eudicot species shows that there have been independent expansions of the family in monocots and eudicots. spi1 belongs to a monocot-specific clade, within which the role of individual YUC genes has diversified. These observations, together with expression and functional data, suggest that spi1 has evolved a dominant role in auxin biosynthesis that is essential for normal maize inflorescence development. Analysis of the interaction between spi1 and genes regulating auxin transport indicate that auxin transport and biosynthesis function synergistically to regulate the formation of axillary meristems and lateral organs in maize.

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

    Directory of Open Access Journals (Sweden)

    Grażyna Końska

    2014-08-01

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

  9. Lectins, Interconnecting Proteins with Biotechnological/Pharmacological and Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Luana Cassandra Breitenbach Barroso Coelho

    2017-01-01

    Full Text Available Lectins are proteins extensively used in biomedical applications with property to recognize carbohydrates through carbohydrate-binding sites, which identify glycans attached to cell surfaces, glycoconjugates, or free sugars, detecting abnormal cells and biomarkers related to diseases. These lectin abilities promoted interesting results in experimental treatments of immunological diseases, wounds, and cancer. Lectins obtained from virus, microorganisms, algae, animals, and plants were reported as modulators and tool markers in vivo and in vitro; these molecules also play a role in the induction of mitosis and immune responses, contributing for resolution of infections and inflammations. Lectins revealed healing effect through induction of reepithelialization and cicatrization of wounds. Some lectins have been efficient agents against virus, fungi, bacteria, and helminths at low concentrations. Lectin-mediated bioadhesion has been an interesting characteristic for development of drug delivery systems. Lectin histochemistry and lectin-based biosensors are useful to detect transformed tissues and biomarkers related to disease occurrence; antitumor lectins reported are promising for cancer therapy. Here, we address lectins from distinct sources with some biological effect and biotechnological potential in the diagnosis and therapeutic of diseases, highlighting many advances in this growing field.

  10. Lectins, Interconnecting Proteins with Biotechnological/Pharmacological and Therapeutic Applications

    Science.gov (United States)

    Silva, Priscila Marcelino dos Santos

    2017-01-01

    Lectins are proteins extensively used in biomedical applications with property to recognize carbohydrates through carbohydrate-binding sites, which identify glycans attached to cell surfaces, glycoconjugates, or free sugars, detecting abnormal cells and biomarkers related to diseases. These lectin abilities promoted interesting results in experimental treatments of immunological diseases, wounds, and cancer. Lectins obtained from virus, microorganisms, algae, animals, and plants were reported as modulators and tool markers in vivo and in vitro; these molecules also play a role in the induction of mitosis and immune responses, contributing for resolution of infections and inflammations. Lectins revealed healing effect through induction of reepithelialization and cicatrization of wounds. Some lectins have been efficient agents against virus, fungi, bacteria, and helminths at low concentrations. Lectin-mediated bioadhesion has been an interesting characteristic for development of drug delivery systems. Lectin histochemistry and lectin-based biosensors are useful to detect transformed tissues and biomarkers related to disease occurrence; antitumor lectins reported are promising for cancer therapy. Here, we address lectins from distinct sources with some biological effect and biotechnological potential in the diagnosis and therapeutic of diseases, highlighting many advances in this growing field. PMID:28367220

  11. Lectin cDNA and transgenic plants derived therefrom

    Science.gov (United States)

    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.

  12. Lectin histochemistry of the boar bulbourethral glands

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    E Badia

    2009-06-01

    Full Text Available The present study describes, for the first time, the glycosidic content of boar bulbourethral glands using lectin histochemistry. Fourteen horseradish peroxidase- or digoxigeninlabelled lectins with different carbohydrate specificities were used in samples obtained from 3 healthy Landrace boars. The results obtained indicate that endpiece and duct cells synthesize and secrete mainly O-glycoproteins with a- and b-D-N-acetylgalactosamine, b-D-galactose-b(1®3-D-Nacetylgalactosamine, D-N-acetylglucosamine and neuraminic acid residues. Glycoproteins secreted by bulbourethral glands have a role in the protection and lubrication of the urethra. In addition, they may be also involved in the regulation of the sperm metabolic activity and in the maintenance of the structural integrity of acrosomal and plasma membranes.

  13. The Lectin Pathway of Complement and Biocompatibility

    DEFF Research Database (Denmark)

    Hein, Estrid; Garred, Peter

    2015-01-01

    In modern health technologies the use of biomaterials in the form of stents, haemodialysis tubes, artificial implants, bypass circuits etc. is rapidly expanding. The exposure of synthetic, foreign surfaces to the blood and tissue of the host, calls for strict biocompatibility in respect to contac...... been broadly documented. However, the specific role of lectin pathway and the pattern recognition molecules initiating the pathway has only been transiently investigated. Here we review the current data on the field....... activation, the coagulation system and the complement system. The complement system is an important part of the initial immune response and consists of fluid phase molecules in the blood stream. Three different activation pathways can initiate the complement system, the lectin, the classical...

  14. Are Vicilins Another Major Class of Legume Lectins?

    Directory of Open Access Journals (Sweden)

    Ana C. Ribeiro

    2014-12-01

    Full Text Available Legume lectins comprise a structurally related, Ca/Mn-dependent, widespread, abundant and well characterized lectin family when compared to the large number of lectins from other sources described in the literature. Strangely enough, no specific function has been assigned to them aside from a possible role in storage and/or defense. Using a recent and fine-tuned methodology capable of specific lectin identification, β-conglutin, Vicia faba vicilin and β-lathyrin, the vicilin storage globulins from Lupinus albus, V. faba and Lathyrus sativus, respectively, were shown to be capable of affinity binding to thoroughly washed erythrocyte membranes and of specific elution with appropriate sugars. Based on this evidence and on sparse data published in the literature, a second family of legume lectins is proposed: the 7S family of storage proteins from leguminous seeds, or family II of legume lectins. These lectins are also structurally related, widespread and well characterized. In addition, they self-aggregate in a Ca/Mg, electrostatic dependent manner and are even more abundant than the family I of legume lectins. Using the same evidence, reserve and defense roles may be attributed to family II of legume lectins.

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

    Science.gov (United States)

    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.

  16. Algal Lectins as Potential HIV Microbicide Candidates

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    Dominique Schols

    2012-07-01

    Full Text Available The development and use of topical microbicides potentially offers an additional strategy to reduce the spread of the Human Immunodeficiency Virus (HIV. Carbohydrate-binding agents (CBAs that show specificity for high mannose carbohydrates on the surface of the heavily glycosylated envelope of HIV are endowed with potent anti-HIV activity. In fact, a number of algal lectins such as cyanovirin-N, microvirin, microcystis viridis lectin, scytovirin, Oscillatoria agardhii agglutinin and griffithsin are considered as potential microbicide candidates to prevent the sexual transmission of HIV through topical applications. They not only inhibit infection of cells by cell-free virus but they can also efficiently prevent virus transmission from virus-infected cells to uninfected CD4+ target T-lymphocytes and DC-SIGN-directed capture of HIV-1 and transmission to CD4+ T lymphocytes. This review focuses on the structural properties and carbohydrate specificity of these algal lectins, their antiviral activity against HIV and several other enveloped viruses, their safety profile and viral resistance patterns.

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

    Directory of Open Access Journals (Sweden)

    Kevin Bellande

    2017-05-01

    Full Text Available 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.

  18. Inhibition of Haemonchus contortus larval development by fungal lectins.

    Science.gov (United States)

    Heim, Christian; Hertzberg, Hubertus; Butschi, Alex; Bleuler-Martinez, Silvia; Aebi, Markus; Deplazes, Peter; Künzler, Markus; Štefanić, Saša

    2015-08-19

    Lectins are carbohydrate-binding proteins that are involved in fundamental intra- and extracellular biological processes. They occur ubiquitously in nature and are especially abundant in plants and fungi. It has been well established that certain higher fungi produce lectins in their fruiting bodies and/or sclerotia as a part of their natural resistance against free-living fungivorous nematodes and other pests. Despite relatively high diversity of the glycan structures in nature, many of the glycans targeted by fungal lectins are conserved among organisms of the same taxon and sometimes even among different taxa. Such conservation of glycans between free-living and parasitic nematodes is providing us with a useful tool for discovery of novel chemotherapeutic and vaccine targets. In our study, a subset of fungal lectins emanating from toxicity screens on Caenorhabditis elegans was tested for their potential to inhibit larval development of Haemonchus contortus. The effect of Coprinopsis cinerea lectins - CCL2, CGL2, CGL3; Aleuria aurantia lectin - AAL; Marasmius oreades agglutinin - MOA; and Laccaria bicolor lectin - Lb-Tec2, on cultivated Haemonchus contortus larval stages was investigated using a larval development test (LDT). To validate the results of the toxicity assay and determine lectin binding capacity to the nematode digestive tract, biotinylated versions of lectins were fed to pre-infective larval stages of H. contortus and visualized by fluorescent microscopy. Lectin histochemistry on fixed adult worms was performed to investigate the presence and localisation of lectin binding sites in the disease-relevant developmental stage. Using an improved larval development test we found that four of the six tested lectins: AAL, CCL2, MOA and CGL2, exhibited a dose-dependent toxicity in LDT, as measured by the number of larvae developing to the L3 stage. In the case of AAL, CGL2 and MOA lectin, doses as low as 5 μg/ml caused >95 % inhibition of larval

  19. Identification and characterization of NF-Y transcription factor families in the monocot model plant Brachypodium distachyon.

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    Shuanghe Cao

    Full Text Available BACKGROUND: Nuclear Factor Y (NF-Y is a heterotrimeric transcription factor composed of NF-YA, NF-YB and NF-YC proteins. Using the dicot plant model system Arabidopsis thaliana (Arabidopsis, NF-Y were previously shown to control a variety of agronomically important traits, including drought tolerance, flowering time, and seed development. The aim of the current research was to identify and characterize NF-Y families in the emerging monocot model plant Brachypodium distachyon (Brachypodium with the long term goal of assisting in the translation of known dicot NF-Y functions to the grasses. METHODOLOGY/PRINCIPAL FINDINGS: We identified, annotated, and further characterized 7 NF-YA, 17 NF-YB, and 12 NF-YC proteins in Brachypodium (BdNF-Y. By examining phylogenetic relationships, orthology predictions, and tissue-specific expression patterns for all 36 BdNF-Y, we proposed numerous examples of likely functional conservation between dicots and monocots. To test one of these orthology predictions, we demonstrated that a BdNF-YB with predicted orthology to Arabidopsis floral-promoting NF-Y proteins can rescue a late flowering Arabidopsis mutant. CONCLUSIONS/SIGNIFICANCE: The Brachypodium genome encodes a similar complement of NF-Y to other sequenced angiosperms. Information regarding NF-Y phylogenetic relationships, predicted orthologies, and expression patterns can facilitate their study in the grasses. The current data serves as an entry point for translating many NF-Y functions from dicots to the genetically tractable monocot model system Brachypodium. In turn, studies of NF-Y function in Brachypodium promise to be more readily translatable to the agriculturally important grasses.

  20. Biosynthesis of the Snowdrop (Galanthus nivalis) Lectin in Ripening Ovaries.

    Science.gov (United States)

    Van Damme, E J; Peumans, W J

    1988-03-01

    The biosynthesis and processing of the Galanthus nivalis agglutinin were studied in vivo in ripening snowdrop ovaries. Using labeling and pulse chase labeling experiments it could be demonstrated that the snowdrop lectin is synthesized as a precursor of relative molecular weight (M(r)) 15,000 which is posttranslationally converted into the authentic lectin polypeptide of M(r) 13,000 with a half-life of about 6 hours. Gel filtration of an extract of [(3)H]leucine labeled ovaries on Sepharose 4B showed that a significant portion of the newly synthesized lectin is associated with the particulate fraction. When the organellar fraction was fractionated on isopycnic sucrose gradients this lectin banded in the same density region as the endoplasmic reticulum (ER) marker enzyme NADH cytochrome c reductase. Both radioactivity in lectin and in enzyme activity shifted towards a higher density in the presence of 2 millimolar Mg-acetate indicating that the labeled lectin was associated with the rough ER. Labeled lectin could be chased from the ER with a half-life of 4 hours and then accumulated in the soluble fraction. Whereas the ER-associated lectin contains exclusively polypeptides of M(r) 15,000 the soluble fraction contains both precursor molecules and mature lectin polypeptides. The snowdrop lectin in the ER is fully capable of binding immobilized mannose. It is associated into tetramers with an appropriate molecular weight of 60,000. These results indicate that newly synthesized snowdrop lectin is transiently associated with the ER before transport and processing.

  1. Combined biochemical and cytological analysis of membrane trafficking using lectins.

    Science.gov (United States)

    Morgan, Gareth W; Kail, Mark; Hollinshead, Michael; Vaux, David J

    2013-10-01

    We have tested the application of high-mannose-binding lectins as analytical reagents to identify N-glycans in the early secretory pathway of HeLa cells during subcellular fractionation and cytochemistry. Post-endoplasmic reticulum (ER) pre-Golgi intermediates were separated from the ER on Nycodenz-sucrose gradients, and the glycan composition of each gradient fraction was profiled using lectin blotting. The fractions containing the post-ER pre-Golgi intermediates are found to contain a subset of N-linked α-mannose glycans that bind the lectins Galanthus nivalis agglutinin (GNA), Pisum sativum agglutinin (PSA), and Lens culinaris agglutinin (LCA) but not lectins binding Golgi-modified glycans. Cytochemical analysis demonstrates that high-mannose-containing glycoproteins are predominantly localized to the ER and the early secretory pathway. Indirect immunofluorescence microscopy revealed that GNA colocalizes with the ER marker protein disulfide isomerase (PDI) and the COPI coat protein β-COP. In situ competition with concanavalin A (ConA), another high-mannose specific lectin, and subsequent GNA lectin histochemistry refined the localization of N-glyans containing nonreducing mannosyl groups, accentuating the GNA vesicular staining. Using GNA and treatments that perturb ER-Golgi transport, we demonstrate that lectins can be used to detect changes in membrane trafficking pathways histochemically. Overall, we find that conjugated plant lectins are effective tools for combinatory biochemical and cytological analysis of membrane trafficking of glycoproteins.

  2. Interaction of native and asialo rat sublingual glycoproteins with lectins.

    Science.gov (United States)

    Wu, A M; Herp, A; Song, S C; Wu, J H; Chang, K S

    1995-01-01

    The binding properties of the rat sublingual glycoprotein (RSL) and its asialo product with lectins were characterized by quantitative precipitin(QPA) and precipitin inhibition(QPIA) assays. Among twenty lectins tested for QPA, native RSL reacted well only with Artocarpus integrifolia (jacalin), but weakly or not at all with the other lectins. However, its asialo product (asialo-RSL) reacted strongly with many Gal and GalNAc specific lectins-it bound best to three of the GalNAc alpha 1-->Ser/Thr (Tn) and/or Gal beta 1-->4GlcNAc (II) active lectins [jacalin, Wistaria floribunda and Ricinus communis agglutinins] and completely precipitated each of these three lectins. Asialo-RSL also reacted well with Abrus precatorius, Glycine max, Bauhinia purpurea alba, and Maclura pomifera agglutinins, and abrin-a, but not with Arachis hypogeae and Dolichos biflorus agglutinins. The interaction between asialo-RSL and lectins were inhibited by either Gal beta 1-->4GlcNAc, p-NO2-phenyl alpha-GalNAc or both. The mapping of the precipitation and inhibition profiles leads to the conclusion that the asialo rat sublingual glycoprotein provides important ligands for II (Gal beta 1-->4GlcNAc beta 1-->) and Tn (GalNAc alpha 1-->Ser/Thr) active lectins.

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

    DEFF Research Database (Denmark)

    Garred, Peter

    2008-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Johan Gardères

    2015-08-01

    Full Text Available 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.

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

    DEFF Research Database (Denmark)

    Genster, Ninette; Takahashi, Minoru; Sekine, Hideharu

    2014-01-01

    in complement activation, pathogen infection, coagulation, host tissue injury and developmental biology have been revealed by in vivo investigations. This review provides an overview of the mice deficient in lectin pathway molecules and highlights some of the most important findings that have resulted from......The lectin pathway of the complement system is initiated when the pattern-recognition molecules, mannose-binding lectin (MBL), ficolins or collectin-11, bind to invading pathogens or damaged host cells. This leads to activation of MBL/ficolin/collectin-11 associated serine proteases (MASPs), which...... in turn activate downstream complement components, ultimately leading to elimination of the pathogen. Mice deficient in the key molecules of lectin pathway of complement have been generated in order to build knowledge of the molecular mechanisms of the lectin pathway in health and disease. Despite...

  6. Diversified Carbohydrate-Binding Lectins from Marine Resources

    Directory of Open Access Journals (Sweden)

    Tomohisa Ogawa

    2011-01-01

    Full Text Available Marine bioresources produce a great variety of specific and potent bioactive molecules including natural organic compounds such as fatty acids, polysaccharides, polyether, peptides, proteins, and enzymes. Lectins are also one of the promising candidates for useful therapeutic agents because they can recognize the specific carbohydrate structures such as proteoglycans, glycoproteins, and glycolipids, resulting in the regulation of various cells via glycoconjugates and their physiological and pathological phenomenon through the host-pathogen interactions and cell-cell communications. Here, we review the multiple lectins from marine resources including fishes and sea invertebrate in terms of their structure-activity relationships and molecular evolution. Especially, we focus on the unique structural properties and molecular evolution of C-type lectins, galectin, F-type lectin, and rhamnose-binding lectin families.

  7. Current status of lectin-based cancer diagnosis and therapy

    Directory of Open Access Journals (Sweden)

    Fohona S. Coulibaly

    2017-01-01

    Full Text Available Lectins are carbohydrate recognizing proteins originating from diverse origins in nature, including animals, plants, viruses, bacteria and fungus. Due to their exceptional glycan recognition property, they have found many applications in analytical chemistry, biotechnology and surface chemistry. This manuscript explores the current use of lectins for cancer diagnosis and therapy. Moreover, novel drug delivery strategies aiming at improving lectin’s stability, reducing their undesired toxicity and controlling their non-specific binding interactions are discussed. We also explore the nanotechnology application of lectins for cancer targeting and imaging. Although many investigations are being conducted in the field of lectinology, there is still a limited clinical translation of the major findings reported due to lectins stability and toxicity concerns. Therefore, new investigations of safe and effective drug delivery system strategies for lectins are warranted in order to take full advantage of these proteins.

  8. OsWRKY22, a monocot WRKY gene, plays a role in the resistance response to blast.

    Science.gov (United States)

    Abbruscato, Pamela; Nepusz, Tamás; Mizzi, Luca; Del Corvo, Marcello; Morandini, Piero; Fumasoni, Irene; Michel, Corinne; Paccanaro, Alberto; Guiderdoni, Emmanuel; Schaffrath, Ulrich; Morel, Jean-Benoît; Piffanelli, Pietro; Faivre-Rampant, Odile

    2012-10-01

    With the aim of identifying novel regulators of host and nonhost resistance to fungi in rice, we carried out a systematic mutant screen of mutagenized lines. Two mutant wrky22 knockout lines revealed clear-cut enhanced susceptibility to both virulent and avirulent Magnaporthe oryzae strains and altered cellular responses to nonhost Magnaporthe grisea and Blumeria graminis fungi. In addition, the analysis of the pathogen responses of 24 overexpressor OsWRKY22 lines revealed enhanced resistance phenotypes on infection with virulent M. oryzae strain, confirming that OsWRKY22 is involved in rice resistance to blast. Bioinformatic analyses determined that the OsWRKY22 gene belongs to a well-defined cluster of monocot-specific WRKYs. The co-regulatory analysis revealed no significant co-regulation of OsWRKY22 with a representative panel of OsWRKYs, supporting its unique role in a series of transcriptional responses. In contrast, inquiring a subset of biotic stress-related Affymetrix data, a large number of resistance and defence-related genes were found to be putatively co-expressed with OsWRKY22. Taken together, all gathered experimental evidence places the monocot-specific OsWRKY22 gene at the convergence point of signal transduction circuits in response to both host and nonhost fungi encountering rice plants.

  9. A high throughput barley stripe mosaic virus vector for virus induced gene silencing in monocots and dicots.

    Directory of Open Access Journals (Sweden)

    Cheng Yuan

    Full Text Available Barley stripe mosaic virus (BSMV is a single-stranded RNA virus with three genome components designated alpha, beta, and gamma. BSMV vectors have previously been shown to be efficient virus induced gene silencing (VIGS vehicles in barley and wheat and have provided important information about host genes functioning during pathogenesis as well as various aspects of genes functioning in development. To permit more effective use of BSMV VIGS for functional genomics experiments, we have developed an Agrobacterium delivery system for BSMV and have coupled this with a ligation independent cloning (LIC strategy to mediate efficient cloning of host genes. Infiltrated Nicotiana benthamiana leaves provided excellent sources of virus for secondary BSMV infections and VIGS in cereals. The Agro/LIC BSMV VIGS vectors were able to function in high efficiency down regulation of phytoene desaturase (PDS, magnesium chelatase subunit H (ChlH, and plastid transketolase (TK gene silencing in N. benthamiana and in the monocots, wheat, barley, and the model grass, Brachypodium distachyon. Suppression of an Arabidopsis orthologue cloned from wheat (TaPMR5 also interfered with wheat powdery mildew (Blumeria graminis f. sp. tritici infections in a manner similar to that of the A. thaliana PMR5 loss-of-function allele. These results imply that the PMR5 gene has maintained similar functions across monocot and dicot families. Our BSMV VIGS system provides substantial advantages in expense, cloning efficiency, ease of manipulation and ability to apply VIGS for high throughput genomics studies.

  10. The phylogenetically-related pattern recognition receptors EFR and XA21 recruit similar immune signaling components in monocots and dicots.

    Directory of Open Access Journals (Sweden)

    Nicholas Holton

    2015-01-01

    Full Text Available During plant immunity, surface-localized pattern recognition receptors (PRRs recognize pathogen-associated molecular patterns (PAMPs. The transfer of PRRs between plant species is a promising strategy for engineering broad-spectrum disease resistance. Thus, there is a great interest in understanding the mechanisms of PRR-mediated resistance across different plant species. Two well-characterized plant PRRs are the leucine-rich repeat receptor kinases (LRR-RKs EFR and XA21 from Arabidopsis thaliana (Arabidopsis and rice, respectively. Interestingly, despite being evolutionary distant, EFR and XA21 are phylogenetically closely related and are both members of the sub-family XII of LRR-RKs that contains numerous potential PRRs. Here, we compared the ability of these related PRRs to engage immune signaling across the monocots-dicots taxonomic divide. Using chimera between Arabidopsis EFR and rice XA21, we show that the kinase domain of the rice XA21 is functional in triggering elf18-induced signaling and quantitative immunity to the bacteria Pseudomonas syringae pv. tomato (Pto DC3000 and Agrobacterium tumefaciens in Arabidopsis. Furthermore, the EFR:XA21 chimera associates dynamically in a ligand-dependent manner with known components of the EFR complex. Conversely, EFR associates with Arabidopsis orthologues of rice XA21-interacting proteins, which appear to be involved in EFR-mediated signaling and immunity in Arabidopsis. Our work indicates the overall functional conservation of immune components acting downstream of distinct LRR-RK-type PRRs between monocots and dicots.

  11. Comparative genomics of multiple strains of Pseudomonas cannabina pv. alisalensis, a potential model pathogen of both monocots and dicots.

    Directory of Open Access Journals (Sweden)

    Panagiotis F Sarris

    Full Text Available Comparative genomics of closely related pathogens that differ in host range can provide insights into mechanisms of host-pathogen interactions and host adaptation. Furthermore, sequencing of multiple strains with the same host range reveals information concerning pathogen diversity and the molecular basis of virulence. Here we present a comparative analysis of draft genome sequences for four strains of Pseudomonas cannabina pathovar alisalensis (Pcal, which is pathogenic on a range of monocotyledonous and dicotyledonous plants. These draft genome sequences provide a foundation for understanding host range evolution across the monocot-dicot divide. Like other phytopathogenic pseudomonads, Pcal strains harboured a hrp/hrc gene cluster that codes for a type III secretion system. Phylogenetic analysis based on the hrp/hrc cluster genes/proteins, suggests localized recombination and functional divergence within the hrp/hrc cluster. Despite significant conservation of overall genetic content across Pcal genomes, comparison of type III effector repertoires reinforced previous molecular data suggesting the existence of two distinct lineages within this pathovar. Furthermore, all Pcal strains analyzed harbored two distinct genomic islands predicted to code for type VI secretion systems (T6SSs. While one of these systems was orthologous to known P. syringae T6SSs, the other more closely resembled a T6SS found within P. aeruginosa. In summary, our study provides a foundation to unravel Pcal adaptation to both monocot and dicot hosts and provides genetic insights into the mechanisms underlying pathogenicity.

  12. Characterization of barley (Hordeum vulgare L. NAC transcription factors suggests conserved functions compared to both monocots and dicots

    Directory of Open Access Journals (Sweden)

    Gregersen Per L

    2011-08-01

    Full Text Available Abstract Background The NAC transcription factor family is involved in the regulation of traits in both monocots and dicots of high agronomic importance. Understanding the precise functions of the NAC genes can be of utmost importance for the improvement of cereal crop plants through plant breeding. For the cereal crop plant barley (Hordeum vulgare L. only a few NAC genes have so far been investigated. Results Through searches in publicly available barley sequence databases we have obtained a list of 48 barley NAC genes (HvNACs with 43 of them representing full-length coding sequences. Phylogenetic comparisons to Brachypodium, rice, and Arabidopsis NAC proteins indicate that the barley NAC family includes members from all of the eight NAC subfamilies, although by comparison to these species a number of HvNACs still remains to be identified. Using qRT-PCR we investigated the expression profiles of 46 HvNACs across eight barley tissues (young flag leaf, senescing flag leaf, young ear, old ear, milk grain, late dough grain, roots, and developing stem and two hormone treatments (abscisic acid and methyl jasmonate. Conclusions Comparisons of expression profiles of selected barley NAC genes with the published functions of closely related NAC genes from other plant species, including both monocots and dicots, suggest conserved functions in the areas of secondary cell wall biosynthesis, leaf senescence, root development, seed development, and hormone regulated stress responses.

  13. Enhancement of innate immune system in monocot rice by transferring the dicotyledonous elongation factor Tu receptor EFR

    Institute of Scientific and Technical Information of China (English)

    Fen Lu; Huiqin Wang; Shanzhi Wang; Wendi Jiang; Changlin Shan; Bin Li; Jun Yang; Shiyong Zhang; Wenxian Sun

    2015-01-01

    The elongation factor Tu (EF-Tu) receptor (EFR) in cruciferous plants specifical y recognizes the N-terminal acetylated elf18 region of bacterial EF-Tu and thereby activates plant immunity. It has been demonstrated that Arabidopsis EFR confers broad-spectrum bacterial resistance in the EFR transgenic solanaceous plants. Here, the transgenic rice plants (Oryza sativa L. ssp. japonica cv. Zhonghua 17) and cel cultures with constitutive expression of AtEFR were developed to investigate whether AtEFR senses EF-Tu and thus enhances bacterial resistance in the monocot plants. We demonstrated that the Xanthomonas oryzae-derived elf18 peptide induced oxidative burst and mitogen-activated protein kinase activa-tion in the AtEFR transgenic rice cel s and plants, respectively. Pathogenesis-related genes, such as OsPBZ1, were upregulated dramatical y in transgenic rice plant and cel lines in response to elf18 stimulation. Importantly, pretreatment with elf18 trig-gered strong resistance to X. oryzae pv. oryzae in the transgenic plants, which was largely dependent on the AtEFR expression level. These plants also exhibited enhanced resistance to rice bacterial brown stripe, but not to rice fungal blast. Col ectively, the results indicate that the rice plants with heterologous expression of AtEFR recognize bacterial EF-Tu and exhibit enhanced broad-spectrum bacterial disease resistance and that pattern recognition receptor-mediated immunity may be manipulated across the two plant classes, dicots and monocots.

  14. Ureaplasma urealyticum binds mannose-binding lectin.

    Science.gov (United States)

    Benstein, Barbara D; Ourth, Donald D; Crouse, Dennis T; Shanklin, D Radford

    2004-10-01

    Mannose-binding C-type lectin (MBL) is an important component of innate immunity in mammals. Mannose-binding lectin (MBL), an acute phase protein, acts as an opsonin for phagocytosis and also activates the mannan-binding lectin complement pathway. It may play a particularly significant role during infancy before adequate specific protection can be provided by the adaptive immune system. Ureaplasma urealyticum has been linked to several diseases including pneumonia and chronic lung disease (CLD) in premature infants. We therefore investigated the ability of U. urealyticum to bind MBL. A guinea pig IgG anti-rabbit-MBL antiserum was produced. An immunoblot (dot-blot) assay done on nitrocellulose membrane determined that the anti-MBL antibody had specificity against both rabbit and human MBL. Pure cultures of U. urealyticum, serotype 3, were used to make slide preparations. The slides containing the organisms were then incubated with nonimmune rabbit serum containing MBL. Ureaplasma was shown to bind rabbit MBL with an immunocytochemical assay using the guinea pig IgG anti-rabbit MBL antiserum. Horseradish peroxidase (HRP)-labeled anti-guinea pig IgG was used to localize the reaction. The anti-MBL antiserum was also used in an immunocytochemical assay to localize U. urealyticum in histological sections of lungs from mice specifically infected with this organism. The same method also indicated binding of MBL by ureaplasma in human lung tissue obtained at autopsy from culture positive infants. Our results demonstrate that ureaplasma has the capacity to bind MBL. The absence of MBL may play a role in the predisposition of diseases related to this organism.

  15. Lectin activity in mycelial extracts of Fusarium species

    Directory of Open Access Journals (Sweden)

    Ranjeeta Bhari

    Full Text Available ABSTRACT 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.

  16. Lectin activity in mycelial extracts of Fusarium species.

    Science.gov (United States)

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

    2016-01-01

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

  17. Lectin binding to cystic stages of Taenia taeniaeformis.

    Science.gov (United States)

    Sandeman, R M; Williams, J F

    1984-10-01

    Studies of membrane glycoconjugates of Taenia taeniaeformis were initiated by assays of the lectin binding characteristics of 35-day-old cysticerci. Parasites fixed in glutaraldehyde were incubated with one of the following FITC-labelled lectins: Concanavalin A (Con A), Lens culinaris agglutinin (LCA), Ricinus communis agglutinin (RCA), peanut agglutinin (PNA), fucose binding protein (FBP) and wheat germ agglutinin (WGA) and either their specific or a nonspecific sugar. Ultraviolet microscopy revealed that only Con A and LCA bound in large amounts to the surface of cysticerci. This binding was partly inhibited by the specific sugar, but the nonspecific sugar had little effect. The lectin not removed by either of the sugars may have been bound nonspecifically to the charged glycocalyx. Lectins were primarily bound on the anterior third of the parasite around the scolex invagination. Kinetic studies of lectin interactions were carried out with LCA and RCA by spectrophotofluorometric analysis of the amount bound specifically or nonspecifically over a range of lectin concentrations. Lens culinaris lectin binding was found to be specific and involve 2 receptors which showed large differences in their affinity for lectin and prevalence on the surface. Ricinus communis lectin did not bind specifically but nonspecific interactions were observed. Adherence of small numbers of host cells was shown to have no measurable effect on the lectin binding characteristics. The results suggest that the major surface carbohydrates exposed are D-mannose and/or D-glucose residues with the other sugar groups poorly represented. This relatively homogeneous surface may have implications for the antigenicity of the parasite in its host.

  18. Molecular characterization of a saline-soluble lectin from a parasitic fungus: Extensive sequence similarities between fungal lectins

    NARCIS (Netherlands)

    Rosén, S.; Kata, M.; Persson, Y.; Lipniunas, P.H.; Wikström, M.; Hondel, C.A.M.J.J. van den; Brink, J.M. van den; Rask, L.; Hedén, L.O.; Tunlid, A.

    1996-01-01

    It has been proposed that the interactions between several parasite and pathogenic fungi and their hosts are mediated by soluble lectins present in the fungus. We have cloned and analyzed a gene encoding such a lectin (AOL) from the nematophagous fungus Arthrobotrys oligospora (deuteromycete). The d

  19. Molecular characterization of a saline-soluble lectin from a parasitic fungus: Extensive sequence similarities between fungal lectins

    NARCIS (Netherlands)

    Rosén, S.; Kata, M.; Persson, Y.; Lipniunas, P.H.; Wikström, M.; Hondel, C.A.M.J.J. van den; Brink, J.M. van den; Rask, L.; Hedén, L.O.; Tunlid, A.

    1996-01-01

    It has been proposed that the interactions between several parasite and pathogenic fungi and their hosts are mediated by soluble lectins present in the fungus. We have cloned and analyzed a gene encoding such a lectin (AOL) from the nematophagous fungus Arthrobotrys oligospora (deuteromycete). The

  20. Mannose Binding Lectin Deficiency and Clinical Features

    Directory of Open Access Journals (Sweden)

    Ertugrul Erken

    2013-08-01

    Full Text Available Innate immunity consists of macrophages, neutrophils, natural killer cells, mucosal immunuglobulins and the comlement system. Mannose binding lectin (MBL takes part in innate immunity through opsonisation and complement activation. MBL deficiency is associated with some infections and autoimmune disorders. However some studies indicate that MBL deficiency alone is not essential for immunity but it may intensify the clinic picture of an immune deficiency that already exists. This article refers to clincal studies related to MBL and brings up the clinical importance of MBL deficiency. [Archives Medical Review Journal 2013; 22(4.000: 565-574

  1. Diversification of genes encoding granule-bound starch synthase in monocots and dicots is marked by multiple genome-wide duplication events.

    Directory of Open Access Journals (Sweden)

    Jun Cheng

    Full Text Available Starch is one of the major components of cereals, tubers, and fruits. Genes encoding granule-bound starch synthase (GBSS, which is responsible for amylose synthesis, have been extensively studied in cereals but little is known about them in fruits. Due to their low copy gene number, GBSS genes have been used to study plant phylogenetic and evolutionary relationships. In this study, GBSS genes have been isolated and characterized in three fruit trees, including apple, peach, and orange. Moreover, a comprehensive evolutionary study of GBSS genes has also been conducted between both monocots and eudicots. Results have revealed that genomic structures of GBSS genes in plants are conserved, suggesting they all have evolved from a common ancestor. In addition, the GBSS gene in an ancestral angiosperm must have undergone genome duplication ∼251 million years ago (MYA to generate two families, GBSSI and GBSSII. Both GBSSI and GBSSII are found in monocots; however, GBSSI is absent in eudicots. The ancestral GBSSII must have undergone further divergence when monocots and eudicots split ∼165 MYA. This is consistent with expression profiles of GBSS genes, wherein these profiles are more similar to those of GBSSII in eudicots than to those of GBSSI genes in monocots. In dicots, GBSSII must have undergone further divergence when rosids and asterids split from each other ∼126 MYA. Taken together, these findings suggest that it is GBSSII rather than GBSSI of monocots that have orthologous relationships with GBSS genes of eudicots. Moreover, diversification of GBSS genes is mainly associated with genome-wide duplication events throughout the evolutionary course of history of monocots and eudicots.

  2. Noncovalent PEGylation via Lectin-Glycopolymer Interactions.

    Science.gov (United States)

    Antonik, Paweł M; Eissa, Ahmed M; Round, Adam R; Cameron, Neil R; Crowley, Peter B

    2016-08-08

    PEGylation, the covalent modification of proteins with polyethylene glycol, is an abundantly used technique to improve the pharmacokinetics of therapeutic proteins. The drawback with this methodology is that the covalently attached PEG can impede the biological activity (e.g., reduced receptor-binding capacity). Protein therapeutics with "disposable" PEG modifiers have potential advantages over the current technology. Here, we show that a protein-polymer "Medusa complex" is formed by the combination of a hexavalent lectin with a glycopolymer. Using NMR spectroscopy, small-angle X-ray scattering (SAXS), size exclusion chromatography, and native gel electrophoresis it was demonstrated that the fucose-binding lectin RSL and a fucose-capped polyethylene glycol (Fuc-PEG) form a multimeric assembly. All of the experimental methods provided evidence of noncovalent PEGylation with a concomitant increase in molecular mass and hydrodynamic radius. The affinity of the protein-polymer complex was determined by ITC and competition experiments to be in the micromolar range, suggesting that such systems have potential biomedical applications.

  3. A Phylogeny of the Monocots, as Inferred from rbcL and atpA Sequence Variation, and a Comparison of Methods for Calculating Jackknife and Bootstrap Values

    DEFF Research Database (Denmark)

    Davis, Jerrold I.; Stevenson, Dennis W.; Petersen, Gitte;

    2004-01-01

    A phylogenetic analysis of the monocots was conducted on the basis of nucleotide sequence variation in two genes (atpA, encoded in the mitochondrial genome, and rbcL, encoded in the plastid genome). The taxon sample of 218 angiosperm terminals included 177 monocots and 41 dicots. Among the major ...

  4. Lectin domains at the frontiers of plant defense

    Directory of Open Access Journals (Sweden)

    Nausicaä eLANNOO

    2014-08-01

    Full Text Available Plants are under constant attack from pathogens and herbivorous insects. To protect and defend themselves, plants evolved a multi-layered surveillance system, known as the innate immune system. Plants sense their encounters upon perception of conserved microbial structures and damage-associated patterns using cell-surface and intracellular immune receptors. Plant lectins and proteins with one or more lectin domains represent a major part of these receptors. The whole group of plant lectins comprises an elaborate collection of proteins capable of recognizing and interacting with specific carbohydrate structures, either originating from the invading organisms or from damaged plant cell wall structures. Due to the vast diversity in protein structures, carbohydrate recognition domains and glycan binding specificities, plant lectins constitute a very diverse protein superfamily. In the last decade, new types of nucleocytoplasmic plant lectins have been identified and characterized, in particular lectins expressed inside the nucleus and the cytoplasm of plant cells often as part of a specific plant response upon exposure to different stress factors or changing environmental conditions. In this review, we provide an overview on plant lectin motifs used in the constant battle against pathogens and predators during plant defenses.

  5. New sensitive detection method for lectin hemagglutination using microscopy.

    Science.gov (United States)

    Adamová, Lenka; Malinovská, Lenka; Wimmerová, Michaela

    2014-10-01

    The blood group system AB0 is determined by the composition of terminal oligosaccharides on red blood cells. Thanks to this structural feature, these groups can be recognized by saccharide-recognizing compounds. Lectins are proteins that are able to reversibly bind saccharide structures. They generally occur as multimers and are known as hemagglutination agents. Hemagglutination is a process in which blood cells are cross-linked via multivalent molecules. Apart from lectins, hemagglutination can also be caused by antibodies or viruses. A hemagglutination assay is commonly used for the detection of multivalent molecules that recognize blood cells, in order to search for their sugar specificity. It is traditionally performed on a microtiter plate, where the lectin solution is serially diluted and the lowest concentration of lectin causing agglutination is detected. This experimental set-up is utilized further for testing lectin specificity via a hemagglutination inhibition assay. We have developed a new way of detecting hemagglutination using microscopy, which was tested on purified lectins as well as cell lysates. Hemagglutination was performed on a microscope slide directly and detected using a microscope. Comparison with the standard hemagglutination assay using microtiter plates revealed that microscopic approach is faster and more robust and allows fast determination of lectin activities immediately in bacterial cytosols.

  6. Self-assembled carbohydrate-based vesicles for lectin targeting.

    Science.gov (United States)

    Dos Santos, Marinalva Cardoso; Micheletto, Yasmine Miguel Serafini; da Silveira, Nadya Pesce; da Silva Pinto, Luciano; Giacomelli, Fernando Carlos; de Lima, Vânia Rodrigues; Frizon, Tiago Elias Allievi; Dal-Bó, Alexandre Gonçalves

    2016-12-01

    This study examined the physicochemical interactions between vesicles formed by phosphatidylcholine (PC) and glycosylated polymeric amphiphile N-acetyl-β-d-glucosaminyl-PEG900-docosanate (C22PEG900GlcNAc) conjugated with Bauhinia variegata lectin (BVL). Lectins are proteins or glycoproteins capable of binding glycosylated membrane components. Accordingly, the surface functionalization by such entities is considered a potential strategy for targeted drug delivery. We observed increased hydrodynamic radii (RH) of PC+C22PEG900GlcNAc vesicles in the presence of lectins, suggesting that this aggregation was due to the interaction between lectins and the vesicular glycosylated surfaces. Furthermore, changes in the zeta potential of the vesicles with increasing lectin concentrations implied that the vesicular glycosylated surfaces were recognized by the investigated lectin. The presence of carbohydrate residues on vesicle surfaces and the ability of the vesicles to establish specific interactions with BVL were further explored using atomic force microscopy (AFM) and small-angle X-ray scattering (SAXS) analysis. The results indicated that the thickness of the hydrophilic layer was to some extent influenced by the presence of lectins. The presence of lectins required a higher degree of polydispersity as indicated by the width parameter of the log-normal distribution of size, which also suggested more irregular structures. Reflectance Fourier transform infrared (HATR-FTIR), differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR) and ultraviolet-visible (UV-vis.) analyses revealed that the studied lectin preferentially interacted with the choline and carbonyl groups of the lipid, thereby changing the choline orientation and intermolecular interactions. The protein also discretely reduced the intermolecular communication of the hydrophobic acyl chains, resulting in a disordered state.

  7. Plant lectins and their blastogenic and mitogenic activities

    Energy Technology Data Exchange (ETDEWEB)

    Nag, S.; Talukder, G.; Sharma, A.

    1981-01-01

    The lectins can stimulate the transformation of lymphocytes from small resting cells into large blast-like cells which may ultimately undergo mitotic division. The stimulation of lymphocytes by lectins is also an important tool for the examination of biochemical events involved in the conversion of a resting cell into an actively growing one. Properties of mitogenic phytolectins and metabolic changes associated with stimulation are examined. Although mitogenic lectins have been obtained from a variety of different plants, most of our knowledge concerning the biochemical properties and mechanism of their activation in different test systems has been gathered from Phaseolus vulgaris (PHA) and Canavalia ensiformis (Con-A) as group prototypes.

  8. Nuevas citas de monocotiledóneas adventicias para la Argentina New records of adventitious monocots for Argentina

    Directory of Open Access Journals (Sweden)

    Julio A. Hurrell

    2009-12-01

    Full Text Available Este trabajo incluye cinco nuevos registros de monocotiledóneas adventicias para la Argentina: Aloe ciliaris Haw. (Asphodelaceae, Aspidistra elatior Blume (Convallariaceae, Sansevieria trifasciata Prain (Dracaenaceae, Phormium tenax J. R. Forst. & G. Forst. (Hemerocallidaceae y Ornithogalum arabicum L. (Hyacinthaceae, pertenecientes al orden Asparagales. También incluye una evaluación del estado actual de estas especies, en relación al proceso de naturalización: escapadas de cultivo ocasionales, naturalizadas.This paper includes five new records of adventitious monocots for Argentina: Aloe ciliaris Haw. (Asphodelaceae, Aspidistra elatior Blume (Convallariaceae, Sansevieria trifasciata Prain (Dracaenaceae, Phormium tenax J. R. Forst. & G. Forst. (Hemerocallidaceae and Ornithogalum arabicum L. (Hyacinthaceae, belonging to order Asparagales. Also includes an evaluation of its status in the naturalization process: casual alien, naturalized.

  9. Fine specificities of two lectins from Cymbosema roseum seeds: a lectin specific for high-mannose oligosaccharides and a lectin specific for blood group H type II trisaccharide.

    Science.gov (United States)

    Dam, Tarun K; Cavada, Benildo S; Nagano, Celso S; Rocha, Bruno Am; Benevides, Raquel G; Nascimento, Kyria S; de Sousa, Luiz Ag; Oscarson, Stefan; Brewer, C Fred

    2011-07-01

    The legume species of Cymbosema roseum of Diocleinae subtribe produce at least two different seed lectins. The present study demonstrates that C. roseum lectin I (CRL I) binds with high affinity to the "core" trimannoside of N-linked oligosaccharides. Cymbosema roseum lectin II (CRL II), on the other hand, binds with high affinity to the blood group H trisaccharide (Fucα1,2Galα1-4GlcNAc-). Thermodynamic and hemagglutination inhibition studies reveal the fine binding specificities of the two lectins. Data obtained with a complete set of monodeoxy analogs of the core trimannoside indicate that CRL I recognizes the 3-, 4- and 6-hydroxyl groups of the α(1,6) Man residue, the 3- and 4-hydroxyl group of the α(1,3) Man residue and the 2- and 4-hydroxyl groups of the central Man residue of the trimannoside. CRL I possesses enhanced affinities for the Man5 oligomannose glycan and a biantennary complex glycan as well as glycoproteins containing high-mannose glycans. On the other hand, CRL II distinguishes the blood group H type II epitope from the Lewis(x), Lewis(y), Lewis(a) and Lewis(b) epitopes. CRL II also distinguishes between blood group H type II and type I trisaccharides. CRL I and CRL II, respectively, possess differences in fine specificities when compared with other reported mannose and fucose recognizing lectins. This is the first report of a mannose-specific lectin (CRL I) and a blood group H type II-specific lectin (CRL II) from seeds of a member of the Diocleinae subtribe.

  10. Gene duplication and an accelerated evolutionary rate in 11S globulin genes are associated with higher protein synthesis in dicots as compared to monocots

    Directory of Open Access Journals (Sweden)

    Li Chun

    2012-01-01

    Full Text Available Abstract Background Seed storage proteins are a major source of dietary protein, and the content of such proteins determines both the quantity and quality of crop yield. Significantly, examination of the protein content in the seeds of crop plants shows a distinct difference between monocots and dicots. Thus, it is expected that there are different evolutionary patterns in the genes underlying protein synthesis in the seeds of these two groups of plants. Results Gene duplication, evolutionary rate and positive selection of a major gene family of seed storage proteins (the 11S globulin genes, were compared in dicots and monocots. The results, obtained from five species in each group, show more gene duplications, a higher evolutionary rate and positive selections of this gene family in dicots, which are rich in 11S globulins, but not in the monocots. Conclusion Our findings provide evidence to support the suggestion that gene duplication and an accelerated evolutionary rate may be associated with higher protein synthesis in dicots as compared to monocots.

  11. Lumichrome and riboflavin are two novel symbiotic signals eliciting developmental changes in both monocot and dicot plant species

    Directory of Open Access Journals (Sweden)

    Felix Dapare Dakora

    2015-09-01

    Full Text Available Lumichrome and riboflavin are novel molecules from rhizobial exudates that stimulate plant growth. Developmental changes elicited by lumichrome at very low nanomolar concentrations (5 nM include early initiation of trifoliate leaves, expansion of unifoliate and trifoliate leaves, increased stem elongation and leaf area, and consequently greater biomass accumulation in monocots and dicots. However, higher lumichrome concentration (50 nM depressed root development and reduced growth of unifoliate and second trifoliate leaves. Applying either 10 nM lumichrome, 10 nM ABA, or 10 ml of infective rhizobial cells (0.2 OD600 to roots of monocots and dicots for 44 h produced identical effects, which included decreased stomatal conductance and leaf transpiration in Bambara groundnut, soybean and maize, increased stomatal conductance and transpiration in cowpea and lupin, and elevated root respiration in maize (19% by rhizobia and 20% by lumichrome. Extracellular exudation of lumichrome, riboflavin and IAA was greater in N2-fixing rhizobia than non-fixing bacteria, indicating their role as symbiotic signals. Xylem concentration of lumichrome in cowpea and soybean was greater in plants inoculated with infective rhizobia and treated with lumichrome (61.2 µmol lumichrome.ml-1 sap, followed by uninoculated plants receiving lumichrome (41.12 µmol lumichrome.ml-1 sap, and lowest in uninoculated, lumichrome-free plants (26.8 µmol lumichrome.ml-1 sap. Overall, soybean showed greater xylem concentration of lumichrome and a correspondingly increased accumulation in leaves relative to cowpea. As a result, soybean exhibited dramatic developmental changes than cowpea. Taken together, lumichrome and riboflavin secreted by soil rhizobia function as environmental cues for sensing stress. The fact that exogenous application of ABA to plant roots caused the same effect as lumichrome on stomatal functioning suggests molecular cross-talk in plant response to environmental

  12. [Galectins, a class of unconventional lectins].

    Science.gov (United States)

    Advedissian, Tamara; Deshayes, Frédérique; Poirier, Françoise; Grandjean, Cyrille; Viguier, Mireille

    2015-05-01

    Galectins constitute a family of soluble animal lectins defined by their evolutionary conserved carbohydrate recognition domain and their affinity for β-galactosides containing glycoconjugates. Each galectin is characterized by a specific spatio-temporal distribution and a unique set of ligands and molecular partners. Interestingly, galectins are found both extracellularly and intracellularly and modulate various cellular processes. Knock-out mutant mice for galectins-1, 3 or 7 are viable but display a wide range of defects under various stress conditions. Indeed, galectins are multifunctional proteins involved in cell-cell and cell-extracellular matrix interactions, organization of membrane domains, cell signalling and also in intracellular trafficking, apoptosis, regulation of cell cycle. Galectins represent potential therapeutic targets, especially in the context of cancer and inflammatory diseases.

  13. Narcissus tazetta lectin shows strong inhibitory effects against respiratory syncytial virus, influenza A (H1N1, H3N2, H5N1) and B viruses

    Indian Academy of Sciences (India)

    Linda S M Ooi; Wing-Shan Ho; Karry L K Ngai; Li Tian; Paul K S Chan; Samuel S M Sun; Vincent E C Ooi

    2010-03-01

    Amannose-binding lectin (Narcissus tazetta lectin [NTL]) with potent antiviral activity was isolated and purified from the bulbs of the Chinese daffodil Narcissus tazetta var. chinensis, using ion exchange chromatography on diethylaminoethyl (DEAE)-cellulose, affinity chromatography on mannose–agarose and fast protein liquid chromatography (FPLC)-gel filtration on Superose 12. The purified lectin was shown to have an apparent molecular mass of 26 kDa by gel filtration and 13 kDa by SDS–PAGE, indicating that it is probably a dimer with two identical subunits. The cDNA-derived amino acid sequence of NTL as determined by molecular cloning also reveals that NTL protein contains a mature polypeptide consisting of 105 amino acids and a C-terminal peptide extension. Three-dimensional modelling study demonstrated that the NTL primary polypeptide contains three subdomains, each with a conserved mannose-binding site. It shows a high homology of about 60%–80% similarity with the existing monocot mannose-binding lectins. NTL could significantly inhibit plaque formation by the human respiratory syncytial virus (RSV) with an IC50 of 2.30 g/ml and exhibit strong antiviral properties against influenza A (H1N1, H3N2, H5N1) and influenza B viruses with IC50 values ranging from 0.20 g/ml to 1.33 g/ml in a dose-dependent manner. It is worth noting that the modes of antiviral action of NTL against RSV and influenza A virus are significantly different. NTL is effective in the inhibition of RSV during the whole viral infection cycle, but the antiviral activity of NTL is mainly expressed at the early stage of the viral cycle of influenza A (H1N1) virus. NTL with a high selective index (SI=CC50/IC50 ≥ 141) resulting from its potent antiviral activity and low cytotoxicity demonstrates a potential for biotechnological development as an antiviral agent.

  14. Insights into Animal and Plant Lectins with Antimicrobial Activities

    Directory of Open Access Journals (Sweden)

    Renata de Oliveira Dias

    2015-01-01

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

  15. The role of thrombomodulin lectin-like domain in inflammation

    Directory of Open Access Journals (Sweden)

    Li Yi-Heng

    2012-03-01

    Full Text Available Abstract Thrombomodulin (TM is a cell surface glycoprotein which is widely expressed in a variety of cell types. It is a cofactor for thrombin binding that mediates protein C activation and inhibits thrombin activity. In addition to its anticoagulant activity, recent evidence has revealed that TM, especially its lectin-like domain, has potent anti-inflammatory function through a variety of molecular mechanisms. The lectin-like domain of TM plays an important role in suppressing inflammation independent of the TM anticoagulant activity. This article makes an extensive review of the role of TM in inflammation. The molecular targets of TM lectin-like domain have also been elucidated. Recombinant TM protein, especially the TM lectin-like domain may play a promising role in the management of sepsis, glomerulonephritis and arthritis. These data demonstrated the potential therapeutic role of TM in the treatment of inflammatory diseases.

  16. Human Lectins and Their Roles in Viral Infections

    Directory of Open Access Journals (Sweden)

    Christopher P. Mason

    2015-01-01

    Full Text Available Innate recognition of virus proteins is an important component of the immune response to viral pathogens. A component of this immune recognition is the family of lectins; pattern recognition receptors (PRRs that recognise viral pathogen-associated molecular patterns (PAMPs including viral glycoproteins. In this review we discuss the contribution of soluble and membrane-associated PRRs to immunity against virus pathogens, and the potential role of these molecules in facilitating virus replication. These processes are illustrated with examples of viruses including human immunodeficiency virus (HIV, hepatitis C virus (HCV and Ebola virus (EBOV. We focus on the structure, function and genetics of the well-characterised C-type lectin mannose-binding lectin, the ficolins, and the membrane-bound CD209 proteins expressed on dendritic cells. The potential for lectin-based antiviral therapies is also discussed.

  17. Comparing mannose binding lectin genetic diversity in intracellular ...

    African Journals Online (AJOL)

    SERVER

    2007-09-05

    Sep 5, 2007 ... mannose binding lectin level for susceptibility to intracellular pathogens. Key words: .... The distribution of alleles and genotypes between groups were compared using ... Frequency of promoter variants and position +4 (Table.

  18. Lentinula edodes Biotechnology – From Lentinan to Lectins

    Directory of Open Access Journals (Sweden)

    Valentina E. Nikitina

    2007-01-01

    Full Text Available Lentinula edodes was the first medicinal macrofungus to enter the realm of modern biotechnology. The present paper briefly reviews the history of the modern biotechnology of this mushroom starting with the production of the polysaccharide preparation lentinan, and ending with an overview of our own work regarding the production of lectins. Our work with lectins has involved studies of the effect of initial pH, carbon and nitrogen sources and the C:N ratio on lectin production in both the mycelium and culture medium. We have shown that lectin activity is related to morphological development, with the activity being highest in extracts of the pigmented mycelial films that precede fruiting body production.

  19. Isolation and characterization of a lectin from Annona muricata seeds.

    Science.gov (United States)

    Damico, D C S; Freire, M G M; Gomes, V M; Toyama, M H; Marangoni, S; Novello, J C; Macedo, M L R

    2003-11-01

    A lectin with a high affinity for glucose/mannose was isolated from Annona muricata seeds (Annonaceae) by gel filtration chromatography on Sephacryl S-200, ion exchange chromatography on a DEAE SP-5 PW column, and molecular exclusion on a Protein Pak Glass 300 SW column. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (PAGE) yielded two protein bands of approximately 14 kDa and 22 kDa. However, only one band was seen in native PAGE. The Mr of the lectin estimated by fast-performance liquid chromatography-gel filtration on Superdex 75 was 22 kDa. The lectin was a glycoprotein with 8% carbohydrate (neutral sugar) and required divalent metal cations (Ca2+, Mg2+, and Mn2+) for full activity. Amino acid analysis revealed a large content of Glx, Gly, Phe, and Lys. The lectin agglutinated dog, chicken, horse, goose, and human erythrocytes and inhibited the growth of the fungi Fusarium oxysporum, Fusarium solani, and Colletotrichum musae.

  20. Detection of Lectins by Saccharide-gold Nanoparticle Conjugates

    Institute of Scientific and Technical Information of China (English)

    HOU Qiong; WANG Jin-e; LIU Xia; LI Xiao-kun; MA Li-na; DUAN Wu-biao; WANG Zhen-xin

    2012-01-01

    A general functionalization strategy was reported,which enables one to conjugate saccharide(SA) on gold nanoparticle(GNP) surface without affecting SA properties.First,disulfide phenylboronic acid(Bor) functionalized GNPs(Bor@GNPs) were synthesized by the reaction of citrate stabilized GNPs of 13 nm in diameter with the mixture of Bor and pentapeptide(Cys-Ala-Leu-Asn-Asn,CALNN).Subsequently,the SA-GNP conjugates(SA@GNPs) were prepared by coupling SA to the GNP surface via the reaction of phenylboronic acid(PBA) with the cis-diol configuration in SA.The interactions of three SA@GNPs with three lectins have been analyzed by UV-visible spectroscopic and transmission electronic microscopic(TEM) techniques,respectively.The experimental results demonstrate that SA@GNPs can efficiently bind to lectins and show a great promise as optical probes for monitoring specific affinities of lectins for SA,and detecting lectins with high sensitivity.

  1. Structure and Function of Mammalian Carbohydrate-Lectin Interactions

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    Monteiro Tínel, Juliana Montezuma Barbosa; Benevides, Melina Fechine Costa; Frutuoso, Mércia Sindeaux; Rocha, Camila Farias; Arruda, Francisco Vassiliepe Sousa; Vasconcelos, Mayron Alves; Pereira-Junior, Francisco Nascimento; Cajazeiras, João Batista; do Nascimento, Kyria Santiago; Martins, Jorge Luiz; Teixeira, Edson Holanda; Cavada, Benildo Sousa; dos Santos, Ricardo Pires; Lima Pompeu, Margarida Maria

    2014-01-01

    Leishmaniasis is a vector-borne disease transmitted by phlebotomine sand fly. Susceptibility and refractoriness to Leishmania depend on the outcome of multiple interactions that take place within the sand fly gut. Promastigote attachment to sand fly midgut epithelium is essential to avoid being excreted together with the digested blood meal. Promastigote and gut sand fly surface glycans are important ligands in this attachment. The purpose of the present study was to evaluate the interaction of three lectins isolated from leguminous seeds (Diocleinae subtribe), D-glucose and D-mannose-binding, with glycans on Lutzomyia migonei midgut. To study this interaction the lectins were labeled with FITC and a fluorescence assay was performed. The results showed that only Dioclea violacea lectin (DVL) was able to interact with midgut glycans, unlike Cratylia floribunda lectin (CFL) and Canavalia gladiata lectin (CGL). Furthermore, when DVL was blocked with D-mannose the interaction was inhibited. Differences of spatial arrangement of residues and volume of carbohydrate recognition domain (CRD) may be the cause of the fine specificity of DVL for glycans in the surface on Lu. migonei midgut. The findings in this study showed the presence of glycans in the midgut with glucose/mannose residues in its composition and these residues may be important in interaction between Lu. migonei midgut and Leishmania. PMID:25431778

  3. Interaction of the tobacco lectin with histone proteins

    OpenAIRE

    Schouppe, Dieter; Ghesquière, Bart; Menschaert, Gerben; De Vos, Winnok; Bourque, Stéphane; Trooskens, Geert; Proost, Paul; Gevaert, Kris; Van Damme, Els

    2011-01-01

    The tobacco (Nicotiana tabacum) agglutinin or Nictaba is a member of a novel class of plant lectins residing in the nucleus and the cytoplasm of tobacco cells. Since tobacco lectin expression is only observed after the plant has been subjected to stress situations such as jasmonate treatment or insect attack, Nictaba is believed to act as a signaling protein involved in the stress physiology of the plant. In this paper, a nuclear proteomics approach was followed to identify the binding partne...

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

    African Journals Online (AJOL)

    SAM

    2014-04-09

    Apr 9, 2014 ... STL-S and STL-D showed 79.84 and 83.04% of growth inhibition of EAC cells, respectively. Additionally ... Plant lectins have been widely studied for pharmaco- .... The Artemia cysts were hatched in artificial seawater at. 28°C under .... and lectin-treated mice counted by a light microscope on day. 6 of tumor ...

  5. A lectin with some unique characteristics from the samta tomato.

    Science.gov (United States)

    Wang, H; Ng, T B

    2006-04-01

    A lectin, with a molecular mass of 79 kDa, and with specificity toward rhamnose and O-nitrophenyl-beta-D-galactopyranoside, was isolated from samta tomato fruits. The procedure entailed ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-cellulose and gel filtration by fast protein liquid chromatography on Superdex 75. The lectin was unadsorbed on DEAE-cellulose but adsorbed on Affi-gel blue gel and CM-cellulose. The lectin was stable up to 70 degrees C. The lectin activity was potentiated by NaOH solutions (25-100 mM), but was reduced by 50 and 100 mM HCl solutions. The activity of the lectin was reduced in the presence of CaCl(2), MgCl(2) and ZnCl(2), but was potentiated by 5 and 10 mM AlCl(3) solutions. The lectin stimulated the mitogenic response in mouse splenocytes and inhibited human immunodeficiency virus-1 reverse transcriptase with an IC(50) of 6.2 microM.

  6. Structures and binding specificity of galactose- and mannose-binding lectins from champedak: differences from jackfruit lectins.

    Science.gov (United States)

    Gabrielsen, Mads; Abdul-Rahman, Puteri Shafinaz; Othman, Shatrah; Hashim, Onn H; Cogdell, Richard J

    2014-06-01

    Galactose-binding and mannose-binding lectins from the champedak fruit, which is native to South-east Asia, exhibit useful potential clinical applications. The specificity of the two lectins for their respective ligands allows the detection of potential cancer biomarkers and monitoring of the glycosylated state of proteins in human serum and/or urine. To fully understand and expand the use of these natural proteins, their complete sequences and crystal structures are presented here, together with details of sugar binding.

  7. Pinellia ternata lectin exerts a pro-inflammatory effect on macrophages by inducing the release of pro-inflammatory cytokines, the activation of the nuclear factor-κB signaling pathway and the overproduction of reactive oxygen species.

    Science.gov (United States)

    Yu, Hong-Li; Zhao, Teng-Fei; Wu, Hao; Pan, Yao-Zong; Zhang, Qian; Wang, Kui-Long; Zhang, Chen-Chao; Jin, Yang-Ping

    2015-10-01

    Pinellia ternata (PT) is a widely used traditional Chinese medicine. The raw material has a throat-irritating toxicity that is associated with the PT lectin (PTL). PTL is a monocot lectin isolated from the tubers of PT, which exhibits mouse peritoneal acute inflammatory effects in vivo. The present study aimed to investigate the pro-inflammatory effect of PTL on macrophages. PTL (50 µg/ml)‑stimulated macrophages enhanced the chemotactic activity of neutrophils. PTL (50, 100, 200 and 400 µg/ml) significantly elevated the production of cytokines [tumor necrosis factor‑α (TNF-α) , interleukin (IL)‑1β and IL‑6]. PTL (25, 50 and 100 µg/ml) induced intracellular reactive oxygen species (ROS) overproduction. PTL also caused transfer of p65 from the macrophage cytoplasm to the nucleus and activated the nuclear factor‑κB (NF‑κB) signaling pathway. Scanning electron microscope images revealed severe cell swelling and membrane integrity defection of macrophages following PTL (100 µg/ml) stimulation, which was also associated with inflammation. PTL had pro‑inflammatory activity, involving induced neutrophil migration, cytokine release, ROS overproduction and the activation of the NF-κB signaling pathway, which was associated with the activation of macrophages.

  8. Lectin-like molecules in transcriptome of Littorina littorea hemocytes.

    Science.gov (United States)

    Gorbushin, Alexander M; Borisova, Elena A

    2015-01-01

    The common periwinkle Littorina littorea was introduced in the list of models for comparative immunobiology as a representative of phylogenetically important taxon Caenogastropoda. Using Illumina sequencing technology, we de novo assembled the transcriptome of Littorina littorea hemocytes from 182 million mRNA-Seq pair-end 100 bp reads into a total of 15,526 contigs clustered in 4472 unigenes. The transcriptome profile was analyzed for presence of carbohydrate-binding molecules in a variety of architectural contexts. Hemocytes' repertoire of lectin-like proteins bearing conserved carbohydrate-recognition domains (CRDs) is highly diversified, including 11 of 15 lectin families earlier described in animals, as well as the novel members of lectin family found for the first time in mollusc species. The new molluscan lineage-specific domain combinations were confirmed by cloning and sequencing, including the fuco-lectin related molecules (FLReMs) composed of N-terminal region with no sequence homology to any known protein, a middle Fucolectin Tachylectin-4 Pentaxrin (FTP) domain, and a C-terminal epidermal growth factor (EGF) repeat region. The repertoire of lectin-like molecules is discussed in terms of their potential participation in the receptor phase of immune response. In total, immune-associated functions may be attributed to 70 transcripts belonging to 6 lectin families. These lectin-like genes show low overlap between species of invertebrates, suggesting relatively rapid evolution of immune-associated genes in the group. The repertoire provides valuable candidates for further characterization of the gene functions in mollusc immunity.

  9. Lectins binding during alloxan-induced diabetes in rat soleus muscle

    African Journals Online (AJOL)

    SERVER

    2008-04-17

    Apr 17, 2008 ... Diabetes mellitus is a metabolic disorder of multiple aetiology characterized by ... aortic smooth muscle cell of rabbits (Alpui et al., 1993). The mechanism of ... Lectins used and their carbohydrate specificities. Source of lectin.

  10. Mannan-Binding Lectin in Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Izabela Pągowska-Klimek

    2014-01-01

    Full Text Available Cardiovascular disease remains the leading cause of mortality and morbidity worldwide so research continues into underlying mechanisms. Since innate immunity and its potent component mannan-binding lectin have been proven to play an important role in the inflammatory response during infection and ischaemia-reperfusion injury, attention has been paid to its role in the development of cardiovascular complications as well. This review provides a general outline of the structure and genetic polymorphism of MBL and its role in inflammation/tissue injury with emphasis on associations with cardiovascular disease. MBL appears to be involved in the pathogenesis of atherosclerosis and, in consequence, coronary artery disease and also inflammation and tissue injury after myocardial infarction and heart transplantation. The relationship between MBL and disease is rather complex and depends on different genetic and environmental factors. That could be why the data obtained from animal and clinical studies are sometimes contradictory proving not for the first time that innate immunity is a “double-edge sword,” sometimes beneficial and, at other times disastrous for the host.

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

    Science.gov (United States)

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

    2013-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Gustavo M S G Moreira

    Full Text Available 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.

  13. Lectin Activity in Gut Extract of Culex pipiens.

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    Mona Koosha

    2013-06-01

    Full Text Available The role of lectins is important in interaction between pathogens and mosquito vectors. This study was performed to identify agglutinin activities of protein molecules on the midgut of Culex pipiens.Culex pipiens was reared in insectray condition and the midguts of males and females (blood fed and unfed were dissected separately in Tris-HCl buffer. The extracts of midguts were applied for hemagglutinin assay against red blood cells of rabbit, mouse, rat, dog, horse, sheep, guinea pig, cow, human (A, B, AB, O groups. Then, the RBCs with relatively high agglutinin activity were chosen for carbohydrate inhibition assay. D (+ glucose, D (+ galactose, D (+ mannose, D (- fructose, D (- arabinose, L (- fucose, lactose, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, sialic acid were used to specify carbohydrate binding lectin.The highest agglutinin activities were found against sheep and rabbits RBCs. Sexual diversity of agglutinin activities was observed among midgut extraction of males and females. In addition, variation in agglutinin activity of blood fed and unfed female mosquitoes were detected. The lectin activity was inhibited highly with glucose, galactose, fucose and fructose but less inhibitor activities was observed by arabinose, N-acetyl-D-galactosamine, n-acetyl-d-glucosamine, lactose and mannose.The secretion of hemagglutinins (lectins or lectin-like molecules in the digestive system depends on the type of food in the gut. This suggests that emptying of the gut in preparation for protein rich food probably starts the secretion of hemagglutinins.

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

    Science.gov (United States)

    Chan, Yau Sang; Ng, Tzi Bun

    2015-01-01

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

  15. Lectin Activity in Gut Extract of Culex pipiens

    Science.gov (United States)

    Koosha, Mona; Abai, Mohammad Reza; Abolhasani, Mandan; Charedar, Soroor; Basseri, Hamid Reza

    2013-01-01

    Background: The role of lectins is important in interaction between pathogens and mosquito vectors. This study was performed to identify agglutinin activities of protein molecules on the midgut of Culex pipiens. Methods: Culex pipiens was reared in insectray condition and the midguts of males and females (blood fed and unfed) were dissected separately in Tris-HCl buffer. The extracts of midguts were applied for hemagglutinin assay against red blood cells of rabbit, mouse, rat, dog, horse, sheep, guinea pig, cow, human (A, B, AB, O groups). Then, the RBCs with relatively high agglutinin activity were chosen for carbohydrate inhibition assay. D (+) glucose, D (+) galactose, D (+) mannose, D (−) fructose, D (−) arabinose, L (−) fucose, lactose, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, sialic acid were used to specify carbohydrate binding lectin. Results: The highest agglutinin activities were found against sheep and rabbits RBCs. Sexual diversity of agglutinin activities was observed among midgut extraction of males and females. In addition, variation in agglutinin activity of blood fed and unfed female mosquitoes were detected. The lectin activity was inhibited highly with glucose, galactose, fucose and fructose but less inhibitor activities was observed by arabinose, N-acetyl-D-galactosamine, n-acetyl-d-glucosamine, lactose and mannose. Conclusion: The secretion of hemagglutinins (lectins or lectin-like molecules) in the digestive system depends on the type of food in the gut. This suggests that emptying of the gut in preparation for protein rich food probably starts the secretion of hemagglutinins. PMID:23785692

  16. The interaction of fish trypanosome culture forms with some lectins.

    Science.gov (United States)

    Zajícek, P; Pecková, H

    1990-01-01

    The interactions of fish trypanosome culture forms with 11 purified lectins were compared using the agglutination test in microwell plates. Altogether, ten stocks of ten different freshwater fish species were examined. Three basic types of cell-lectin interactions were observed on the microscopical level. The strong agglutination of all stocks regardless their original host was found in the presence of Con A, PSA, RCA60, and RCA120, which implies the presence of relatively high amounts of sugar residues of D-mannose and D-galactose in the surface of culture forms of these parasites. Weak agglutinations of some stocks were observed in the presence of LCA, PNA, SBA, and WGA lectins, but their low intensity makes them not sufficiently reliable for stock characterization. The lectins UEA I, HPA, and PHA caused no agglutination. In conclusion, in case of unequivocal results no remarkable differences in the interactions of various stocks of trypanosomes culture forms with used lectins were observed. These results imply the high degree of similarity of their main cell surface saccharide structures.

  17. Effects of Plant Lectins on Human Erythrocyte Agglutination

    Directory of Open Access Journals (Sweden)

    Zubcevic Nadja

    2016-09-01

    Full Text Available Plant lectins are carbohydrate binding proteins or phytohaemagglutinins present in most plants, especially seeds and tubers, which include cereals, potatoes and beans. Lectins have great significance in the diet because of their involvement in gastrointestinal difficulties and erythrocyte agglutination. Blood agglutination activity against A, B, AB and O groups was shown after exposing blood to extracts obtained from 55% of tested plants, while in 45% of plants, agglutination was absent. The results of our study have shown that in humans, 40% of plant extracts exhibited activity against A, 40% of plant extracts exhibited activity against B, and 50% of plant extracts exhibited activity against AB and O groups in humans. The concentration of plant lectins depends on the part of the plant. Lectins from the seeds of certain plants cause the greatest percentage of erythrocyte agglutination, while the lowest agglutination was caused by plant bulbs and leaves. However, lectins derived from all plant species of the family Fabaceae agglutinated erythrocytes of all blood types to some extent.

  18. Structural variations among monocot emergent and amphibious species from lakes of the semi-arid region of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    KRB Leite

    Full Text Available Temporary lakes are common in the semi-arid region of the State of Bahia and form water mirrors in the rainy season. In this period, various vegetal species appear having different life forms adapted to the seasonality conditions of the rainfall regime. This work surveyed the adaptive anatomical structures of some emergent and amphibious monocot species occurring in these lakes. We studied the anatomy of roots, rhizomes, leaves and scapes of Cyperus odoratus, Oxycaryum cubense, Pycreus macrostachyos (Cyperaceae - amphibious species; and of Echinodorus grandiflorus (Alismataceae, Eichhornia paniculata (Pontederiaceae and Habenaria repens (Orchidaceae - emergent species. The anatomical features of the dermal, fundamental and vascular systems confirming the tendency of the adaptive convergence of these plants to temporary lacustrine the environment include: single layered epidermal cells with a thin cuticle layer in the aerial organs; the presence of air canals in all the organs; few or no supporting tissues; and less numerous conducting elements and thinner cell walls in the xylem. The reduction of the supporting tissues, the number of stomata, which can even be absent, and the number of conducting elements and the degree of cell wall lignification in the xylem of the emergent species is more accentuated than that of the amphibious species. The pattern of distribution of aerenchyma in the roots of the studied species was considered important to distinguish between amphibious and emergent life forms.

  19. Transcriptome analysis during somatic embryogenesis of the tropical monocot Elaeis guineensis: evidence for conserved gene functions in early development.

    Science.gov (United States)

    Lin, Hsiang-Chun; Morcillo, Fabienne; Dussert, Stéphane; Tranchant-Dubreuil, Christine; Tregear, James W; Tranbarger, Timothy John

    2009-05-01

    With the aim of understanding the molecular mechanisms underlying somatic embryogenesis (SE) in oil palm, we examined transcriptome changes that occur when embryogenic suspension cells are initiated to develop somatic embryos. Two reciprocal suppression subtractive hybridization (SSH) libraries were constructed from oil palm embryogenic cell suspensions: one in which embryo development was blocked by the presence of the synthetic auxin analogue 2,4-dichlorophenoxyacetic acid (2,4-D: ) in the medium (proliferation library); and another in which cells were stimulated to form embryos by the removal of 2,4-D: from the medium (initiation library). A total of 1867 Expressed Sequence Tags (ESTs) consisting of 1567 potential unigenes were assembled from the two libraries. Functional annotation indicated that 928 of the ESTs correspond to proteins that have either no similarity to sequences in public databases or are of unknown function. Gene Ontology (GO) terms assigned to the two EST populations give clues to the underlying molecular functions, biological processes and cellular components involved in the initiation of embryo development. Macroarrays were used for transcript profiling the ESTs during SE. Hierarchical cluster analysis of differential transcript accumulation revealed 4 distinct profiles containing a total of 192 statistically significant developmentally regulated transcripts. Similarities and differences between the global results obtained with in vitro systems from dicots, monocots and gymnosperms will be discussed.

  20. Efficient, Antibiotic Marker-Free Transformation of a Dicot and a Monocot Crop with Glutamate 1-Semialdehyde Aminotransferase Selectable Marker Genes.

    Science.gov (United States)

    Ferradini, Nicoletta; Giancaspro, Angelica; Nicolia, Alessandro; Gadaleta, Agata; Veronesi, Fabio; Rosellini, Daniele

    2016-01-01

    Antibiotic-free, efficient in vitro selection in plant genetic engineering can improve risk perception and speed up pre-market scrutiny of genetically modified crops. We provide a protocol for genetic transformation of two important crops, durum wheat and alfalfa, using a bacterial and a plant-derived selectable marker gene encoding mutated, gabaculine-insensitive glutamate 1-semialdehyde aminotransferase (GSA) enzymes. These methods can potentially be applied, with minor adaptations, to many other monocot and dicot crop plants.

  1. Recombinant lectins: an array of tailor-made glycan-interaction biosynthetic tools.

    Science.gov (United States)

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

    2013-03-01

    Lectins are a heterogeneous group of proteins found in plants, animals and microorganisms, which possess at least one non-catalytic domain that binds reversibly to specific mono- or oligosaccharides. The range of lectins and respective biological activities is unsurprising given the immense diversity and complexity of glycan structures and the multiple modes of interaction with proteins. Recombinant DNA technology has been traditionally used for cloning and characterizing newly discovered lectins. It has also been employed as a means of producing pure and sequence-defined lectins for different biotechnological applications. This review focuses on the production of recombinant lectins in heterologous organisms, and highlighting the Escherichia coli and Pichia pastoris expression systems, which are the most employed. The choice of expression host depends on the lectin. Non-glycosylated recombinant lectins are produced in E. coli and post-translational modified recombinant lectins are produced in eukaryotic organisms, namely P. pastoris and non-microbial hosts such as mammalian cells. Emphasis is given to the applications of the recombinant lectins especially (a) in cancer diagnosis and/or therapeutics, (b) as anti-microbial, anti-viral, and anti-insect molecules or (c) in microarrays for glycome profiling. Most reported applications are from recombinant plant lectins. These applications benefit from the tailor-made design associated with recombinant production and will aid in unraveling the complex biological mechanisms of glycan-interactions, bringing recombinant lectins to the forefront of glycobiology. In conclusion, recombinant lectins are developing into valuable biosynthetic tools for biomedical research.

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

    Lifescience Database Archive (English)

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

  3. Production and purification of active snowdrop lectin in Escherichia coli.

    Science.gov (United States)

    Longstaff, M; Powell, K S; Gatehouse, J A; Raemaekers, R; Newell, C A; Hamilton, W D

    1998-02-15

    Recombinant snowdrop lectin was produced in Escherichia coli from a cDNA clone encoding mature Galanthus nivalis agglutinin. After induction with isopropylthio-beta-D-galactoside, inclusion bodies from E. coli were solubilised and the G. nivalis agglutinin purified by metal-affinity chromatography using a carboxy-terminal hexahistidine tag. The protein was refolded on the metal-affinity column prior to elution. After purification, the recombinant G. nivalis agglutinin agglutinated rabbit erythrocytes to a dilution similar to that determined for 'native' lectin purified from snowdrop, and showed similar specific binding to mannose. The toxicity of the recombinant G. nivalis agglutinin towards rice brown planthopper (Nilaparvata lugens) was shown to be similar to that of 'native' G. nivalis agglutinin when incorporated into an artificial diet. The recombinant G. nivalis agglutinin is thus functionally similar to 'native' snowdrop lectin.

  4. BSA-boronic acid conjugate as lectin mimetics.

    Science.gov (United States)

    Narla, Satya Nandana; Pinnamaneni, Poornima; Nie, Huan; Li, Yu; Sun, Xue-Long

    2014-01-10

    We report bovine serum albumin (BSA)-boronic acid (BA) conjugates as lectin mimetics and their glyco-capturing capacity. The BSA-BA conjugates were synthesized by amidation of carboxylic acid groups in BSA with aminophenyl boronic acid in the presence of EDC, and were characterized by Alizarin Red S (ARS) assay and SDS-PAGE gel. The BSA-BA conjugates were immobilized onto maleimide-functionalized silica beads and their sugar capturing capacity and specificity were confirmed by ARS displacement assay. Further, surface plasmon resonance (SPR) analysis of the glyco-capturing activity of the BSA-BA conjugates was conducted by immobilizing BSA-BA onto SPR gold chip. Overall, we demonstrated a BSA-BA-based lectin mimetics for glyco-capturing applications. These lectin mimetics are expected to provide an important tool for glycomics and biosensor research and applications.

  5. Parkia pendula lectin as histochemistry marker for meningothelial tumour

    Directory of Open Access Journals (Sweden)

    EIC Beltrão

    2009-06-01

    Full Text Available 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.

  6. Isolation and Biochemical Characterization of Apios Tuber Lectin

    Directory of Open Access Journals (Sweden)

    Eri Kenmochi

    2015-01-01

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

  7. Effect of Lectins from Diocleinae Subtribe against Oral Streptococci

    Directory of Open Access Journals (Sweden)

    Edson Holanda Teixeira

    2011-04-01

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

  8. Erythrina lectins detect the H/HI blood groups.

    Science.gov (United States)

    Sudakevitz, D; Gilboa-Garber, N; Levene, C; Sela, R; Bhattacharyya, L

    1991-08-01

    The lectin purified from Erythrina corallodendron seeds which binds N-acetyllactosamine greater than N-acetyl-D-galactosamine greater than alpha and beta galactosides greater than D-galactose was examined for its ABO(H) blood group specificity. It has been shown that this lectin causes the strongest hemagglutination of O(H) and weakest of Oh(Bombay) red blood cells, and interacts with the H antigen in association with the I antigen. The reactions of Erythrina corallodendron and Erythrina indica lectins (which are similar in sugar specificity) with erythrocytes of different ABO(H) and Ii blood groups (the I bloods were all from adults and the i from either cord or adult bloods) revealed the following order of activity: O(H)I greater than A2 I greater than O(H)i adult greater than A2BI greater than BI greater than O(H)i cord greater than A1I greater than A1i adult greater than Bi cord greater than A1BI greater than Ai cord greater than ABi cord greater than OhI. The Erythrina indica lectin showed a lower differentiation between the agglutination of O(H) and Oh erythrocytes. Both Erythrina lectins exhibited H/HI blood group preference but were not inhibited by the saliva from ABO(H) "secretors". Thus they may be classified with the Cytisus sessilifolius, Lotus tetragonolobus and Laburnum alpinum lectins which are inhibited by lactose but not by H blood group substances in secretions.

  9. Ribosome-inactivating lectins with polynucleotide:adenosine glycosidase activity.

    Science.gov (United States)

    Battelli, M G; Barbieri, L; Bolognesi, A; Buonamici, L; Valbonesi, P; Polito, L; Van Damme, E J; Peumans, W J; Stirpe, F

    1997-05-26

    Lectins from Aegopodium podagraria (APA), Bryonia dioica (BDA), Galanthus nivalis (GNA), Iris hybrid (IRA) and Sambucus nigra (SNAI), and a new lectin-related protein from Sambucus nigra (SNLRP) were studied to ascertain whether they had the properties of ribosome-inactivating proteins (RIP). IRA and SNLRP inhibited protein synthesis by a cell-free system and, at much higher concentrations, by cells and had polynucleotide:adenosine glycosidase activity, thus behaving like non-toxic type 2 (two chain) RIP. APA and SNAI had much less activity, and BDA and GNA did not inhibit protein synthesis.

  10. Structural and functional similarities of breadfruit seed lectin and jacalin.

    Science.gov (United States)

    Pineau, N; Pousset, J L; Preud'Homme, J L; Aucouturier, P

    1990-03-01

    Aquous extracts from seeds of Artocarpus altilis (breadfruit) and Artocarpus heterophyllus (jackfruit) were compared by polyacrylamide gel electrophoresis. Two bands of the same size (12 and 15 kD) as the jacalin subunits were the major components in breadfruit seed extract. They strongly reacted with anti-jacalin antibodies by western blotting. The breadfruit lectin displayed the same IgAl and IgD precipitation specificity as jacalin in gel double diffusion experiments. It also stimulated in vitro proliferation of human peripheral blood mononuclear cells. These results suggest that lectins from both species of Artocarpus are very similar.

  11. INTERACTION BETWEEN THE SURFACE GLYCOSYLATED POLYPROPYLENE MEMBRANE AND LECTIN

    Institute of Scientific and Technical Information of China (English)

    Qian Yang; Ling-shu Wan; Zhi-kang Xu

    2008-01-01

    A glycopolymer bearing glucose residues was tethered onto the surface of polypropylene microporous membrane by UV-induced graft polymerization of α-allyl glucoside. Concanavalin A (Con A), a glucose recognizing lectin, could be specifically adsorbed to the membrane surface. On the other hand, the membrane surface showed no recognition ability to another lectin peanut agglutinin. Moreover, the recognition complex between the glycosylated membrane surface and Con Acould be inhibited by glucose and mannose solution. This surface glycosylated membrane could be used as affinity membrane for protein separation and purification.

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

    DEFF Research Database (Denmark)

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

    1997-01-01

    -linking analysis and SDS-PAGE to be a homo-trimer in solution as are other known members of the collectin family of C-type lectins. Biochemical evidence is presented showing that an N-terminal domain encoded within exons 1 and 2 of the tetranectin gene is necessary and sufficient to govern subunit trimerization.......Tetranectin, a plasminogen-binding protein belonging to the family of C-type lectins, was expressed in E. coli and converted to its native form by in vitro refolding and proteolytic processing. Recombinant tetranectin-as well as natural tetranectin from human plasma-was shown by chemical cross...

  13. Mannan-binding lectin activates C3 and the

    DEFF Research Database (Denmark)

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

    2006-01-01

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

  14. Ferromagnetic Levan Composite: An Affinity Matrix to Purify Lectin

    Directory of Open Access Journals (Sweden)

    Renata Angeli

    2009-01-01

    Full Text Available A simple and inexpensive procedure used magnetite and levan to synthesize a composite recovered by a magnetic field. Lectins from Canavalia ensiformis (Con A and Cratylia mollis (Cramoll 1 and Cramoll 1,4 did bind specifically to composite. The magnetic property of derivative favored washing out contaminating proteins and recovery of pure lectins with glucose elution. Cramoll 1 was purified by this affinity binding procedure in two steps instead of a previous three-step protocol with ammonium sulfate fractionation, affinity chromatography on Sephadex G-75, and ion exchange chromatography through a CM-cellulose column.

  15. Mannan-binding lectin and healing of a radiation-induced chronic ulcer--a case report on mannan-binding lectin replacement therapy

    DEFF Research Database (Denmark)

    Maaløe, Nanna; Bonde, C; Laursen, I

    2011-01-01

    Mannan-binding lectin is an important component of innate immunity, and insufficiency is associated with several clinical disorders. Recently, experimental replacement therapy with plasma-derived mannan-binding lectin has become an option. The current article presents the case of a patient with a...... that deficiency of mannan-binding lectin can explain cases of otherwise unexplained impaired healing, and that replacement therapy is considered in such cases.......Mannan-binding lectin is an important component of innate immunity, and insufficiency is associated with several clinical disorders. Recently, experimental replacement therapy with plasma-derived mannan-binding lectin has become an option. The current article presents the case of a patient...... with an insufficient level of mannan-binding lectin and a chronic radiation-induced ulcer following the treatment of breast cancer. After 15 months of initially conservative treatment and thereafter plastic surgery, the healing was still impaired with necrosis in the periphery of the ulcer. Immunological work...

  16. Interplay between metal binding and cis/trans isomerization in legume lectins: structural and thermodynamic study of P. angolensis lectin.

    Science.gov (United States)

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

    2006-08-04

    The interplay between metal binding, carbohydrate binding activity, stability and structure of the lectin from Pterocarpus angolensis was investigated. Removal of the metals leads to a more flexible form of the protein with significantly less conformational stability. Crystal structures of this metal-free form show significant structural rearrangements, although some structural features that allow the binding of sugars are retained. We propose that substitution of an asparagine residue at the start of the C-terminal beta-strand of the legume lectin monomer hinders the trans-isomerization of the cis-peptide bond upon demetallization and constitutes an intramolecular switch governing the isomer state of the non-proline bond and ultimately the lectin phenotype.

  17. Galactose/N-acetylgalactosamine lectin: the coordinator of host cell killing

    Indian Academy of Sciences (India)

    Douglas R Boettner; Christopher Huston; William A Petri Jr

    2002-11-01

    Entamoeba histolytica is an enteric parasite that can kill host cells via a contact-dependent mechanism. This killing involves the amoebic surface protein referred to as the Gal/GalNAc lectin. The Gal/GalNAc lectin binds galactose and N-acetylgalactosamine allowing the adherence of amoebas to host cells. Involvement of the lectin in the pathogenesis of E. histolytica infection will be reviewed in this paper. The lectin has been shown to have very specific and substantial effects on adherence, cytotoxicity, and encystation. There is also possible involvement of the lectin in phagocytosis and caspase activation in host cells.

  18. A Robust CRISPR/Cas9 System for Convenient, High-Efficiency Multiplex Genome Editing in Monocot and Dicot Plants.

    Science.gov (United States)

    Ma, Xingliang; Zhang, Qunyu; Zhu, Qinlong; Liu, Wei; Chen, Yan; Qiu, Rong; Wang, Bin; Yang, Zhongfang; Li, Heying; Lin, Yuru; Xie, Yongyao; Shen, Rongxin; Chen, Shuifu; Wang, Zhi; Chen, Yuanling; Guo, Jingxin; Chen, Letian; Zhao, Xiucai; Dong, Zhicheng; Liu, Yao-Guang

    2015-08-01

    CRISPR/Cas9 genome targeting systems have been applied to a variety of species. However, most CRISPR/Cas9 systems reported for plants can only modify one or a few target sites. Here, we report a robust CRISPR/Cas9 vector system, utilizing a plant codon optimized Cas9 gene, for convenient and high-efficiency multiplex genome editing in monocot and dicot plants. We designed PCR-based procedures to rapidly generate multiple sgRNA expression cassettes, which can be assembled into the binary CRISPR/Cas9 vectors in one round of cloning by Golden Gate ligation or Gibson Assembly. With this system, we edited 46 target sites in rice with an average 85.4% rate of mutation, mostly in biallelic and homozygous status. We reasoned that about 16% of the homozygous mutations in rice were generated through the non-homologous end-joining mechanism followed by homologous recombination-based repair. We also obtained uniform biallelic, heterozygous, homozygous, and chimeric mutations in Arabidopsis T1 plants. The targeted mutations in both rice and Arabidopsis were heritable. We provide examples of loss-of-function gene mutations in T0 rice and T1 Arabidopsis plants by simultaneous targeting of multiple (up to eight) members of a gene family, multiple genes in a biosynthetic pathway, or multiple sites in a single gene. This system has provided a versatile toolbox for studying functions of multiple genes and gene families in plants for basic research and genetic improvement. Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.

  19. Photosynthetic pigment concentrations, gas exchange and vegetative growth for selected monocots and dicots treated with two contrasting coal fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Yunusa, I.A.M.; Burchett, M.D.; Manoharan, V.; DeSilva, D.L.; Eamus, D.; Skilbeck, C.G. [University of Technology Sydney, Sydney, NSW (Australia). Dept. of Environmental Science

    2009-07-15

    There is uncertainty as to the rates of coal fly ash needed for optimum physiological processes and growth. In the current study we tested the hyothesis that photosynthetic pigments concentrations and CO{sub 2} assimilation (A) are more sensitive than dry weights in plants grown on media amended with coal fly ash. We applied the Terrestrial Plant Growth Test (Guideline 208) protocols of the Organization for Economic Cooperation and Development (OECD) to monocots (barley (Hordeum vulgare) and ryegrass (Secale cereale)) and dicots (canola (Brasica napus), radish (Raphanus sativus), field peas (Pisum sativum), and lucerne (Medicago sativa)) on media amended with fly ashes derived from semi-bituminous (gray ash) or lignite (red ash) coals at rates of 0, 2.5, 5.0, 10, or 20 Mg ha(-1). The red ash had higher elemental concentrations and salinity than the gray ash. Fly ash addition had no significant effect on germination by any of the six species. At moderate rates ({<=}10 Mg ha{sup -1}) both ashes increased (P < 0.05) growth rates and concentrations of chlorophylls a and b, but reduced carotenoid concentrations. Addition of either ash increased A in radish and transpiration in barley. Growth rates and final dry weights were reduced for all of the six test species when addition rates exceeded 10 Mg ha{sup -1} for gray ash and 5 Mg ha{sup -1} for red ash. We concluded that plant dry weights, rather than pigment concentrations and/or instantaneous rates of photosynthesis, are more consistent for assessing subsequent growth in plants supplied with fly ash.

  20. Genetic influences on mannan-binding lectin (MBL) and mannan-binding lectin associated serine protease-2 (MASP-2) activity

    DEFF Research Database (Denmark)

    Sørensen, Grith Lykke; Petersen, Inge; Thiel, Steffen;

    2007-01-01

    The lectin pathway of the complement system is activated when Mannan-binding lectin (MBL) in complex with MASP-2 binds microorganisms. Polymorphisms in both genes are responsible for low serum levels, which associate with increased risk of infection and autoimmune disease. The present study...... of additive genetic factors, shared environmental factors, and non-shared environmental factors. The genetic correlation, i.e., common genetic factors affecting MBL and MASP-2 activity was estimated to r(g) = 0.34 [0.25;0.42]. The data indicate a strong genetic influence for the serum levels of MBL...

  1. Genetic influences on mannan-binding lectin (MBL) and mannan-binding lectin associated serine protease-2 (MASP-2) activity

    DEFF Research Database (Denmark)

    Sørensen, GL; Petersen, I; Thiel, Steffen;

    2007-01-01

    The lectin pathway of the complement system is activated when Mannan-binding lectin (MBL) in complex with MASP-2 binds microorganisms. Polymorphisms in both genes are responsible for low serum levels, which associate with increased risk of infection and autoimmune disease. The present study....... Heritabilites of MBL levels and MASP-2 activity were estimated using structural equation modeling allowing assessment of the contribution of common genes affecting both traits. The estimated heritability was 0.77 [95% CI 0.64;0.91] for MBL levels and 0.75 [95% CI 0.59;0.81] for MASP-2 activity with the presence...

  2. Lectin coated MgO nanoparticle: its toxicity, antileishmanial activity, and macrophage activation.

    Science.gov (United States)

    Jebali, Ali; Hekmatimoghaddam, Seyedhossein; Kazemi, Bahram; Allaveisie, Azra; Masoudi, Alireza; Daliri, Karim; Sedighi, Najme; Ranjbari, Javad

    2014-10-01

    The purpose of this research was to evaluate toxicity of uncoated magnesium oxide nanoparticles (MgO NPs), MgO NPs coated with Peanut agglutinin (PNA) lectin, and PNA alone on the promastigotes of Leishmania major (L. major) and macrophages of BALB/c mice. On the other hand, antileishmanial property of uncoated MgO NPs, lectin coated MgO NPs, and PNA lectin alone was evaluated, and also macrophage activation was investigated after treatment with these materials by measurement of nitrite, H2O2, and some interleukins. This study showed that PNA lectin and lectin coated MgO NPs had approximately no toxicity on L. major and macrophages, but some toxic effects were observed for uncoated MgO NPs, especially at concentration of 500 µg/mL. Interestingly, lectin coated MgO NPs had the highest antileishmanial activity and macrophage activation, compared with uncoated MgO NPs and PNA lectin.

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

    Science.gov (United States)

    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

  4. Multivalent carbohydrate inhibitors of bacterial lectins and toxins

    NARCIS (Netherlands)

    Fu, O.

    2015-01-01

    Bacteria and their toxins often carry proteins on their surface binding to specific components of tissue cells or the extracellular matrix. In many cases the components are carbohydrate structures. The adhesion of these carbohydrate-binding proteins, named lectins, to human glycoconjugates is a

  5. Mannose-Binding Lectin Deficiency Is Associated with Myocardial Infarction

    DEFF Research Database (Denmark)

    Vengen, Inga Thorsen; Madsen, Hans O; Garred, Peter;

    2012-01-01

    Mannose-binding lectin (MBL) and ficolins activate the complement cascade, which is involved in atherogenesis. Based on a pilot study, we hypothesized that functional polymorphisms in the MBL gene (MBL2) leading to dysfunctional protein are related to development of myocardial infarction (MI...

  6. Cancer Biomarker Discovery: Lectin-Based Strategies Targeting Glycoproteins

    Directory of Open Access Journals (Sweden)

    David Clark

    2012-01-01

    Full Text Available Biomarker discovery can identify molecular markers in various cancers that can be used for detection, screening, diagnosis, and monitoring of disease progression. Lectin-affinity is a technique that can be used for the enrichment of glycoproteins from a complex sample, facilitating the discovery of novel cancer biomarkers associated with a disease state.

  7. C-type lectins%C型凝集素

    Institute of Scientific and Technical Information of China (English)

    谢建辉; 顾建新

    2011-01-01

    C型凝集素(C-type lectin)代表一个识别碳水化合物配体依赖于钙离子(Ca2+)参与的糖原结合蛋白家族,含有一个或多个一级结构和二级结构同源的碳水化合物识别结构域.随着研究的深入,越来越多的C型凝集素能够识别体内的非糖类的配体,包括蛋白质和脂类等.这些C型凝集素在维持机体稳态、免疫防御以及免疫监视等重要生理病理过程中发挥着重要作用.就C型凝集素的结构、分类和在免疫系统中的功能作一介绍.%C-type lectins are Ca2+-dependent glycan-binding proteins and share primary and secondary structural homology in their carbohydrate-recognition domains (CRDs). However, many members of this family are recently identified not to bind carbohydrates and have evolved to recognize non-sugar ligands such as proteins and lipids. The large family of C-type lectins has an important role in the physiological functions and pathological processes including immune homeostasis, immune defenses, and immune surveillance and so on. In this short review, we summarize the structure of C-type lectin domain, the classification of C-type lectins and their role in the immune system.

  8. Lectin Activity in Gut Extract of Culex Pipiens

    Directory of Open Access Journals (Sweden)

    Mona Koosha

    2013-03-01

    Full Text Available Background: The role of lectins is important in interaction between pathogens and mosquito vectors. This study was performed to identify agglutinin activities of protein molecules on the midgut of Culex pipiens. Methods: Culex pipiens was reared in insectray condition and the midguts of males and females (blood fed and un­fed were dissected separately in Tris-HCl buffer. The extracts of midguts were applied for hemagglutinin assay against red blood cells of rabbit, mouse, rat, dog, horse, sheep, guinea pig, cow, human (A, B, AB, O groups. Then, the RBCs with relatively high agglutinin activity were chosen for carbohydrate inhibition assay. D (+ glucose, D (+ galactose, D (+ mannose, D (- fructose, D (- arabinose, L (- fucose, lactose, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, sialic acid were used to specify carbohydrate binding lectin.Results: The highest agglutinin activities were found against sheep and rabbits RBCs. Sexual diversity of agglutinin activities was observed among midgut extraction of males and females. In addition, variation in agglutinin activity of blood fed and unfed female mosquitoes were detected. The lectin activity was inhibited highly with glucose, galactose, fucose and fructose but less inhibitor activities was observed by arabinose, N-acetyl-D-galactosamine, n-acetyl-d-glucosamine, lactose and mannose.Conclusion: The secretion of hemagglutinins (lectins or lectin-like molecules in the digestive system depends on the type of food in the gut. This suggests that emptying of the gut in preparation for protein rich food probably starts the secretion of hemagglutinins.

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

    DEFF Research Database (Denmark)

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

    2011-01-01

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

  10. Transcriptome Analysis of Cell Wall and NAC Domain Transcription Factor Genes during Elaeis guineensis Fruit Ripening: Evidence for Widespread Conservation within Monocot and Eudicot Lineages.

    Science.gov (United States)

    Tranbarger, Timothy J; Fooyontphanich, Kim; Roongsattham, Peerapat; Pizot, Maxime; Collin, Myriam; Jantasuriyarat, Chatchawan; Suraninpong, Potjamarn; Tragoonrung, Somvong; Dussert, Stéphane; Verdeil, Jean-Luc; Morcillo, Fabienne

    2017-01-01

    The oil palm (Elaeis guineensis), a monocotyledonous species in the family Arecaceae, has an extraordinarily oil rich fleshy mesocarp, and presents an original model to examine the ripening processes and regulation in this particular monocot fruit. Histochemical analysis and cell parameter measurements revealed cell wall and middle lamella expansion and degradation during ripening and in response to ethylene. Cell wall related transcript profiles suggest a transition from synthesis to degradation is under transcriptional control during ripening, in particular a switch from cellulose, hemicellulose, and pectin synthesis to hydrolysis and degradation. The data provide evidence for the transcriptional activation of expansin, polygalacturonase, mannosidase, beta-galactosidase, and xyloglucan endotransglucosylase/hydrolase proteins in the ripening oil palm mesocarp, suggesting widespread conservation of these activities during ripening for monocotyledonous and eudicotyledonous fruit types. Profiling of the most abundant oil palm polygalacturonase (EgPG4) and 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) transcripts during development and in response to ethylene demonstrated both are sensitive markers of ethylene production and inducible gene expression during mesocarp ripening, and provide evidence for a conserved regulatory module between ethylene and cell wall pectin degradation. A comprehensive analysis of NAC transcription factors confirmed at least 10 transcripts from diverse NAC domain clades are expressed in the mesocarp during ripening, four of which are induced by ethylene treatment, with the two most inducible (EgNAC6 and EgNAC7) phylogenetically similar to the tomato NAC-NOR master-ripening regulator. Overall, the results provide evidence that despite the phylogenetic distance of the oil palm within the family Arecaceae from the most extensively studied monocot banana fruit, it appears ripening of divergent monocot and eudicot fruit lineages are

  11. Isolation and partial characterization of a lectin from ground elder (Aegopodium podagraria) rhizomes.

    Science.gov (United States)

    Peumans, W J; Nsimba-Lubaki, M; Peeters, B; Broekaert, W F

    1985-05-01

    A lectin has been isolated from rhizomes of ground elder (Aegopodium podagraria) using a combination of affinity chromatography on erythrocyte membrane proteins immobilized on cross-linked agarose and hydroxyapatite, and ion-exchange chromatography. The molecular structure of the lectin was determined by gelfiltration, sucrose density-gradient centrifugation and gel electrophoresis under denaturing conditions. It has an unusually high Mr (about 480000) and is most probably an octamer composed of two distinct types of subunits with slightly different Mr (about 60000). Hapten inhibition assays indicated that the Aegopodium lectin is preferentially inhibited by N-acetylgalactosamine. Nevertheless, it does not agglutinate preferentially blood-group-A erythrocytes. The ground-elder lectin is a typical non-seed lectin, which occurs virtually exclusively in the underground rhizomes. In this organ it is an abundant protein as it represents up to 5% of the total protein content. The lectin content of the rhizome tissue varies strongly according to its particular location along the organ. In addition, the lectin content changes dramatically as a function of the seasons. The ground-elder lectin differs from all other plant lectins by its unusually high molecular weight. In addition, it is the first lectin to be isolated from a species of the family Apiaceae.

  12. Microbial F-type lectin domains with affinity for blood group antigens.

    Science.gov (United States)

    Mahajan, Sonal; Khairnar, Aasawari; Bishnoi, Ritika; Ramya, T N C

    2017-09-23

    F-type lectins are fucose binding lectins with characteristic fucose binding and calcium binding motifs. Although they occur with a selective distribution in viruses, prokaryotes and eukaryotes, most biochemical studies have focused on vertebrate F-type lectins. Recently, using sensitive bioinformatics search techniques on the non-redundant database, we had identified many microbial F-type lectin domains with diverse domain organizations. We report here the biochemical characterization of F-type lectin domains from Cyanobium sp. PCC 7001, Myxococcus hansupus and Leucothrix mucor. We demonstrate that while all these three microbial F-type lectin domains bind to the blood group H antigen epitope on fucosylated glycans, there are fine differences in their glycan binding specificity. Cyanobium sp. PCC 7001 F-type lectin domain binds exclusively to extended H type-2 motif, Myxococcus hansupus F-type lectin domain binds to B, H type-1 and Lewis(b) motifs, and Leucothrix mucor F-type lectin domain binds to a wide range of fucosylated glycans, including A, B, H and Lewis antigens. We believe that these microbial lectins will be useful additions to the glycobiologist's toolbox for labeling, isolating and visualizing glycans. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Temporal and spatial expression of polygalacturonase gene family members reveals divergent regulation during fleshy fruit ripening and abscission in the monocot species oil palm

    Directory of Open Access Journals (Sweden)

    Roongsattham Peerapat

    2012-08-01

    Full Text Available Abstract Background Cell separation that occurs during fleshy fruit abscission and dry fruit dehiscence facilitates seed dispersal, the final stage of plant reproductive development. While our understanding of the evolutionary context of cell separation is limited mainly to the eudicot model systems tomato and Arabidopsis, less is known about the mechanisms underlying fruit abscission in crop species, monocots in particular. The polygalacturonase (PG multigene family encodes enzymes involved in the depolymerisation of pectin homogalacturonan within the primary cell wall and middle lamella. PG activity is commonly found in the separation layers during organ abscission and dehiscence, however, little is known about how this gene family has diverged since the separation of monocot and eudicots and the consequence of this divergence on the abscission process. Results The objective of the current study was to identify PGs responsible for the high activity previously observed in the abscission zone (AZ during fruit shedding of the tropical monocot oil palm, and to analyze PG gene expression during oil palm fruit ripening and abscission. We identified 14 transcripts that encode PGs, all of which are expressed in the base of the oil palm fruit. The accumulation of five PG transcripts increase, four decrease and five do not change during ethylene treatments that induce cell separation. One PG transcript (EgPG4 is the most highly induced in the fruit base, with a 700–5000 fold increase during the ethylene treatment. In situ hybridization experiments indicate that the EgPG4 transcript increases preferentially in the AZ cell layers in the base of the fruit in response to ethylene prior to cell separation. Conclusions The expression pattern of EgPG4 is consistent with the temporal and spatial requirements for cell separation to occur during oil palm fruit shedding. The sequence diversity of PGs and the complexity of their expression in the oil palm fruit

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

    DEFF Research Database (Denmark)

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

    2006-01-01

    . It is concluded that the carbohydrate recognizing site of the lectin can have a binding requirement of only one saccharide. Lectin histochemistry was performed on sections from wild type mice and from knock-out mice, which lack function of the alpha.1,3-galactosyltransferase gene. All assays with the P...

  15. Lectin receptors on the plasma membrane of soybean cells. Binding and lateral diffusion of lectins.

    Science.gov (United States)

    Metcalf, T N; Wang, J L; Schubert, K R; Schindler, M

    1983-08-02

    Protoplasts prepared from suspension cultures of root cells of Glycine max (SB-1 cell line) bound soybean agglutinin (SBA), concanavalin A (Con A), and wheat germ agglutinin (WGA). Binding studies carried out with 125I-labeled SBA, Con A, and WGA showed that these interactions were saturable and specific. Fluorescence microscopy demonstrated uniform membrane labeling. The mobility of the lectin-receptor complexes was measured by fluorescence redistribution after photobleaching. The diffusion constants (D) for SBA and Con A were 5 X 10(-11) and 7 X 10(-11) cm2/s, respectively. In contrast, WGA yielded a diffusion constant of 3 X 10(-10) cm2/s. Pretreatment of the protoplasts with either SBA or Con A resulted in a 6-fold reduction in the mobility of WGA (D congruent to 5 X 10(-11) cm2/s). The results suggest that the binding of SBA or Con A may lead to alterations of the soybean plasma membrane which, in turn, may restrict the mobility of other receptors.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    INTRODUCTION: Recent research has focused on the complement system in cancer, including the lectin pathway of complement activation. Mannose-binding lectin (MBL), a key activator of the lectin pathway, can bind to tumor cell surfaces in vitro, and lectin pathway activation is increased in several...... types of cancer. The exact role of the complement system in cancer is currently discussed. However, one possible consequence of the increased complement activation could be contribution to the increased thrombosis risk which cancer patients experience. Proteins of the lectin pathway can activate...... coagulation and impair fibrinolysis in vitro, but the significance of this in a clinical setting is not well understood. AIM: We aim to investigate associations between lectin pathway and haemostatic activation in patients with lung cancer undergoing thoracoscopic surgery. MATERIALS AND METHODS: Patients...

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

    Science.gov (United States)

    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.

  18. A galactose-specific lectin from the hemolymph of the pearl oyster, Pinctada fucata martensii.

    Science.gov (United States)

    Suzuki, T; Mori, K

    1989-01-01

    1. A lectin in the serum of Pinctada fucata martensii was purified by a combination of affinity chromatography on Sepharose 4B coupled with bovine submaxillary gland mucine, anion exchange chromatography on Mono Q and gel filtration on Superose 6. 2. The purified lectin was indicated to be homogeneous by polyacrylamide electrophoresis and rechromatography on Mono Q. 3. The purified lectin was approximately 440,000 in molecular weight and was composed of identical subunits with a molecular weight of approximately 20,000. 4. D-galactose and N-acetylgalactosamine gave a 50% inhibition of agglutination of horse erythrocytes by the lectin at 0.3 and 1.2 mM, respectively. 5. The antibody obtained from rabbit immunized with the purified lectin was monospecific to the lectin judged from the hemagglutination blocking test, immunoelectrophoresis and immunoblotting.

  19. Large Scale Magnetic Separation of Solanum tuberosum Tuber Lectin from Potato Starch Waste Water

    Science.gov (United States)

    Safarik, Ivo; Horska, Katerina; Martinez, Lluis M.; Safarikova, Mirka

    2010-12-01

    A simple procedure for large scale isolation of Solanum tuberosum tuber lectin from potato starch industry waste water has been developed. The procedure employed magnetic chitosan microparticles as an affinity adsorbent. Magnetic separation was performed in a flow-through magnetic separation system. The adsorbed lectin was eluted with glycine/HCl buffer, pH 2.2. The specific activity of separated lectin increased approximately 27 times during the isolation process.

  20. Unique posttranslational modifications of chitin-binding lectins of Entamoeba invadens cyst walls.

    Science.gov (United States)

    Van Dellen, Katrina L; Chatterjee, Anirban; Ratner, Daniel M; Magnelli, Paula E; Cipollo, John F; Steffen, Martin; Robbins, Phillips W; Samuelson, John

    2006-05-01

    Entamoeba histolytica, which causes amebic dysentery and liver abscesses, is spread via chitin-walled cysts. The most abundant protein in the cyst wall of Entamoeba invadens, a model for amebic encystation, is a lectin called EiJacob1. EiJacob1 has five tandemly arrayed, six-Cys chitin-binding domains separated by low-complexity Ser- and Thr-rich spacers. E. histolytica also has numerous predicted Jessie lectins and chitinases, which contain a single, N-terminal eight-Cys chitin-binding domain. We hypothesized that E. invadens cyst walls are composed entirely of proteins with six-Cys or eight-Cys chitin-binding domains and that some of these proteins contain sugars. E. invadens genomic sequences predicted seven Jacob lectins, five Jessie lectins, and three chitinases. Reverse transcription-PCR analysis showed that mRNAs encoding Jacobs, Jessies, and chitinases are increased during E. invadens encystation, while mass spectrometry showed that the cyst wall is composed of an approximately 30:70 mix of Jacob lectins (cross-linking proteins) and Jessie and chitinase lectins (possible enzymes). Three Jacob lectins were cleaved prior to Lys at conserved sites (e.g., TPSVDK) in the Ser- and Thr-rich spacers between chitin-binding domains. A model peptide was cleaved at the same site by papain and E. invadens Cys proteases, suggesting that the latter cleave Jacob lectins in vivo. Some Jacob lectins had O-phosphodiester-linked carbohydrates, which were one to seven hexoses long and had deoxysugars at reducing ends. We concluded that the major protein components of the E. invadens cyst wall all contain chitin-binding domains (chitinases, Jessie lectins, and Jacob lectins) and that the Jacob lectins are differentially modified by site-specific Cys proteases and O-phosphodiester-linked glycans.

  1. Stability, subunit interactions and carbohydrate-binding of the seed lectin from Pterocarpus angolensis.

    Science.gov (United States)

    Echemendia-Blanco, Dannele; Van Driessche, Edilbert; Ncube, Ignatious; Read, John S; Beeckmans, Sonia

    2009-01-01

    From 1 kg of defatted Pterocarpus angolensis (mukwa tree) seed meal, 21.6 grams of an alpha,D-mannose/glucose-specific lectin can be purified on mannose-Sepharose. Relative affinities for several (oligo)saccharides and glycoproteins were studied by haemagglutination-inhibition. Gel filtration shows that the lectin exists as a dimer above pH 5 and as a monomer below pH 3.5. This is confirmed by studies on the release of lectin subunits that were adsorbed from solution to lectin monomers immobilized onto Eupergit-c. From the gel filtration patterns it is calculated that a residue with pK(a) of about 4.4 is involved in dimer dissociation. Titration of glutamic acids (E60, E209) is postulated to be involved. CD spectroscopy shows that the secondary structure of the lectin is unchanged between pH 1 and 12.5, and that the tertiary structure remains unchanged between pH 5 and 12. In the acid pH region, reversible spectral changes occur that may be due to the titration of one or more amino acids with a pK(a) value of 3.9-4.2, probably aspartic acid. These residues are implicated in sugar-binding but not in dimerization of the lectin. Only at pH 12.5, irreversible denaturation occurs. Mukwa lectin displays full carbohydrate-binding capacity between pH 4 and 12, as is concluded from ELLA (Enzyme Linked Lectin Assay) using ovalbumin and fetuin, and from binding of the same glycoproteins to immobilized lectin monomers. The lectin is rapidly and fully reversibly demetallized at pH 2.5 with 5 mM EDTA. The demetallized lectin is completely devoid of sugar-binding activity. Mukwa lectin is a very thermostable molecule (at least till 85 degrees C). However, addition of non-ionic detergents substantially lowers its thermostability.

  2. Soluble Host Defense Lectins in Innate Immunity to Influenza Virus

    Directory of Open Access Journals (Sweden)

    Wy Ching Ng

    2012-01-01

    Full Text Available Host defenses against viral infections depend on a complex interplay of innate (nonspecific and adaptive (specific components. In the early stages of infection, innate mechanisms represent the main line of host defense, acting to limit the spread of virus in host tissues prior to the induction of the adaptive immune response. Serum and lung fluids contain a range of lectins capable of recognizing and destroying influenza A viruses (IAV. Herein, we review the mechanisms by which soluble endogenous lectins mediate anti-IAV activity, including their role in modulating IAV-induced inflammation and disease and their potential as prophylactic and/or therapeutic treatments during severe IAV-induced disease.

  3. Gliadins bind to reticulin in a lectin-like manner.

    Science.gov (United States)

    Unsworth, D J; Leonard, J N; Hobday, C M; Griffiths, C E; Powles, A V; Haffenden, G P; Fry, L

    1987-01-01

    It has previously been reported that gliadins bind to reticulin in tissue sections. Three lines of evidence are reported in this study which indicate that the gliadins bind to reticulins because they are lectins which bind to sugars expressed on glycoproteins in reticulin and other sites. First, immunofluorescence studies on tissue sections showed that although gliadin binding is largely confined to areas rich in reticulin, it is, nonetheless, also seen in one or two other sites devoid of reticulin. Second, by using fluorescein-labelled lectins of known specificity, it has been shown that the areas to which gliadins bind in tissue sections (including those sites devoid of reticulin) are rich in particular sugars. Third, it has been shown that one of these sugars, alpha-D-mannose, partially inhibited gliadin binding to tissue sections.

  4. Griffithsin: An Antiviral Lectin with Outstanding Therapeutic Potential

    Directory of Open Access Journals (Sweden)

    Sabrina Lusvarghi

    2016-10-01

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

  5. C-type lectins in immunity: recent developments

    Science.gov (United States)

    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

  6. Characterization of a 65 kDa NIF in the nuclear matrix of the monocot Allium cepa that interacts with nuclear spectrin-like proteins.

    Science.gov (United States)

    Pérez-Munive, Clara; Blumenthal, Sonal S D; de la Espina, Susana Moreno Díaz

    2012-01-01

    Plant cells have a well organized nucleus and nuclear matrix, but lack orthologues of the main structural components of the metazoan nuclear matrix. Although data is limited, most plant nuclear structural proteins are coiled-coil proteins, such as the NIFs (nuclear intermediate filaments) in Pisum sativum that cross-react with anti-intermediate filament and anti-lamin antibodies, form filaments 6-12 nm in diameter in vitro, and may play the role of lamins. We have investigated the conservation and features of NIFs in a monocot species, Allium cepa, and compared them with onion lamin-like proteins. Polyclonal antisera against the pea 65 kDa NIF were used in 1D and 2D Western blots, ICM (imunofluorescence confocal microscopy) and IEM (immunoelectron microscopy). Their presence in the nuclear matrix was analysed by differential extraction of nuclei, and their association with structural spectrin-like proteins by co-immunoprecipitation and co-localization in ICM. NIF is a conserved structural component of the nucleus and its matrix in monocots with Mr and pI values similar to those of pea 65 kDa NIF, which localized to the nuclear envelope, perichromatin domains and foci, and to the nuclear matrix, interacting directly with structural nuclear spectrin-like proteins. Its similarities with some of the proteins described as onion lamin-like proteins suggest that they are highly related or perhaps the same proteins.

  7. Roothairless5, which functions in maize (Zea mays L.) root hair initiation and elongation encodes a monocot-specific NADPH oxidase.

    Science.gov (United States)

    Nestler, Josefine; Liu, Sanzhen; Wen, Tsui-Jung; Paschold, Anja; Marcon, Caroline; Tang, Ho Man; Li, Delin; Li, Li; Meeley, Robert B; Sakai, Hajime; Bruce, Wesley; Schnable, Patrick S; Hochholdinger, Frank

    2014-09-01

    Root hairs are instrumental for nutrient uptake in monocot cereals. The maize (Zea mays L.) roothairless5 (rth5) mutant displays defects in root hair initiation and elongation manifested by a reduced density and length of root hairs. Map-based cloning revealed that the rth5 gene encodes a monocot-specific NADPH oxidase. RNA-Seq, in situ hybridization and qRT-PCR experiments demonstrated that the rth5 gene displays preferential expression in root hairs but also accumulates to low levels in other tissues. Immunolocalization detected RTH5 proteins in the epidermis of the elongation and differentiation zone of primary roots. Because superoxide and hydrogen peroxide levels are reduced in the tips of growing rth5 mutant root hairs as compared with wild-type, and Reactive oxygen species (ROS) is known to be involved in tip growth, we hypothesize that the RTH5 protein is responsible for establishing the high levels of ROS in the tips of growing root hairs required for elongation. Consistent with this hypothesis, a comparative RNA-Seq analysis of 6-day-old rth5 versus wild-type primary roots revealed significant over-representation of only two gene ontology (GO) classes related to the biological functions (i.e. oxidation/reduction and carbohydrate metabolism) among 893 differentially expressed genes (FDR <5%). Within these two classes the subgroups 'response to oxidative stress' and 'cellulose biosynthesis' were most prominently represented.

  8. Barnacle larval destination: piloting possibilities by bacteria and lectin interaction

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; Anil, A.C.; Raghukumar, S.

    ; Metamorphosis; Balanus amphitrite; Lectins; Pseudomonas aeruginosa; Bacillus pumilus; Citrobacter freundii 1. Introduction Bacterial biofilms are implicated in the settlement process of planktonic larvae of most marine invertebrate groups (Crisp, 1984; Mitchell... have reported stimulation, inhibition or no effect of bacterial films on the attachment of barnacle cyprids (Visscher, 1928; Harris, 1946; Crisp and Meadows, 1962; Tighe-Ford et al., 1970; Neal and Yule, 1994a,b; Maki, 1999). Recently a thraustochytrid...

  9. The Lectin Pathway of Complement and Rheumatic Heart Disease

    Directory of Open Access Journals (Sweden)

    Marcia Holsbach Beltrame

    2015-01-01

    Full Text Available 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 K-1 (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 (RF.

  10. A glycobiology review: carbohydrates, lectins, and implications in cancer therapeutics

    Science.gov (United States)

    Ghazarian, Haike; Idoni, Brian; Oppenheimer, Steven B.

    2010-01-01

    This review is intended for general readers who would like a basic foundation in carbohydrate structure and function, lectin biology and the implications of glycobiology in human health and disease, particularly in cancer therapeutics. These topics are among the hundreds included in the field of glycobiology and are treated here because they form the cornerstone of glycobiology or the focus of many advances in this rapidly expanding field. PMID:20199800

  11. Annotation and genetic diversity of the chicken collagenous lectins.

    Science.gov (United States)

    Hamzić, Edin; Pinard-van der Laan, Marie-Hélène; Bed'Hom, Bertrand; Juul-Madsen, Helle Risdahl

    2015-06-01

    Collectins and ficolins are multimeric proteins present in various tissues and are actively involved in innate immune responses. In chickens, six different collagenous lectins have been characterized so far: mannose-binding lectin (MBL), surfactant protein A (SP-A), collectin 10 (COLEC10), collectin 11 (COLEC11), collectin 12 (COLEC12), lung lectin (LL) and one ficolin (FCN). However, the structural and functional features of the chicken collectins and ficolin are still not fully understood. Therefore, the aims of this study were: (i) to make an overview of the genetic structure and function of chicken collectins and the ficolin, (ii) to investigate the variation in the chicken collectins and the ficolin gene in different chicken populations, and (iii) to assess the presence of MBL gene variants in different chicken populations. We performed comparative genomic analysis using publically available data. The obtained results showed that collectins and ficolins have conserved protein sequences and gene structure across all vertebrate groups and this is especially notable for COLEC10, COLEC11 and COLEC12. For the purpose of studying the genetic variation, 179 animals from 14 populations were genotyped using 31 SNPs covering five genomic regions. The obtained results revealed low level of heterozygosity in the collagenous lectins except for the COLEC12 gene and the LL-SPA-MBL region compared to heterozygosity at neutral microsatellite markers. In addition, the MBL gene variants were assessed in different chicken populations based on the polymorphisms in the promoter region. We observed 10 previously identified MBL variants with A2/A8 and A4 as the most frequent alleles.

  12. Clinical manifestations of mannan-binding lectin deficiency

    DEFF Research Database (Denmark)

    Thiel, Steffen; Frederiksen, Pernille Dorthea; Jensenius, Jens Christian

    2006-01-01

    Mannan-binding lectin (MBL) is a plasma protein of the innate immune system with the ability to initiate antimicrobial and inflammatory actions. MBL deficiency is common. More than 10% of the general population may, depending on definition, be classified as MBL deficient, underlining the redundan...... of the immune system. Ongoing research attempt to illuminate at which conditions MBL deficiency may lead to disease. With examples, this review illustrates the diversity of results obtained so far....

  13. Effects of plant lectins on in vitro fibroblast proliferation

    Directory of Open Access Journals (Sweden)

    Ana Maria Sell

    2003-06-01

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

  14. Lectins as membrane components of mitochondria from Ricinus communis.

    Science.gov (United States)

    Bowles, D J; Schnarrenberger, C; Kauss, H

    1976-01-01

    1. Mitochondria were isolated from developing endosperm of Ricinus communis and were fractionated into outer membrane and inner membrane. The relative purity of the two membrane fractions was determined by marker enzymes. The fractions were also examined by negative-stain electron microscopy. 2. Membrane fractions were sequentially extracted in the following way. (a) Suspension in 0.5M-potassium phosphate, pH7.1; (b)suspension in 0.1M-EDTA (disodium salt)/0.05M-potassium phosphate, pH7.1; (c) sonication in 0.05M-potassium phosphate, pH7.1;(d)sonication in aq. Triton X-100 (0.1%). The membranes were pelleted by centrifugation at 100 000g for 15 min, between each step. Agglutination activity in the extracts was investigated by using trypsin-treated rabbit erythrocytes. 3. The addition of lactose to inner mitochondrial membrane resulted in the solubilization of part of the lectin activity, indicating that the protein was attached to the membrane via its carbohydrate-binding site. Pretreatment of the membranes with lactose before tha usual extraction procedure showed that lactose could extract lectins that normally required more harsh treatment of the membrane for solubilization. 4. Lectins extracted from inner membranes were purified by affinity chromatography on agarose gel. Polyacrylamide-gel electrophoresis of purified samples in sodium dodecyl sulphate indicated that at least part of the lectin present in inner mitochondrial membrane was identical with the R. communis agglutinin of mol.wt. 120 000. Images PLATE 1 PLATE 2 PMID:1008861

  15. Molecular recognition of surface-immobilized carbohydrates by a synthetic lectin

    Directory of Open Access Journals (Sweden)

    Melanie Rauschenberg

    2014-06-01

    Full Text Available The molecular recognition of carbohydrates and proteins mediates a wide range of physiological processes and the development of synthetic carbohydrate receptors (“synthetic lectins” constitutes a key advance in biomedical technology. In this article we report a synthetic lectin that selectively binds to carbohydrates immobilized in a molecular monolayer. Inspired by our previous work, we prepared a fluorescently labeled synthetic lectin consisting of a cyclic dimer of the tripeptide Cys-His-Cys, which forms spontaneously by air oxidation of the monomer. Amine-tethered derivatives of N-acetylneuraminic acid (NANA, β-D-galactose, β-D-glucose and α-D-mannose were microcontact printed on epoxide-terminated self-assembled monolayers. Successive prints resulted in simple microarrays of two carbohydrates. The selectivity of the synthetic lectin was investigated by incubation on the immobilized carbohydrates. Selective binding of the synthetic lectin to immobilized NANA and β-D-galactose was observed by fluorescence microscopy. The selectivity and affinity of the synthetic lectin was screened in competition experiments. In addition, the carbohydrate binding of the synthetic lectin was compared with the carbohydrate binding of the lectins concanavalin A and peanut agglutinin. It was found that the printed carbohydrates retain their characteristic selectivity towards the synthetic and natural lectins and that the recognition of synthetic and natural lectins is strictly orthogonal.

  16. Transmission-blocking antibodies against mosquito C-type lectins for dengue prevention.

    OpenAIRE

    Yang Liu; Fuchun Zhang; Jianying Liu; Xiaoping Xiao; Siyin Zhang; Chengfeng Qin; Ye Xiang; Penghua Wang; Gong Cheng

    2014-01-01

    C-type lectins are a family of proteins with carbohydrate-binding activity. Several C-type lectins in mammals or arthropods are employed as receptors or attachment factors to facilitate flavivirus invasion. We previously identified a C-type lectin in Aedes aegypti, designated as mosquito galactose specific C-type lectin-1 (mosGCTL-1), facilitating the attachment of West Nile virus (WNV) on the cell membrane. Here, we first identified that 9 A. aegypti mosGCTL genes were key susceptibility fac...

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

    Directory of Open Access Journals (Sweden)

    Francisco Vassiliepe Sousa Arruda

    2013-01-01

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

  18. Toxicity and binding profile of lectins from the Genus canavalia on brine shrimp.

    Science.gov (United States)

    Arruda, Francisco Vassiliepe Sousa; Melo, Arthur Alves; Vasconcelos, Mayron Alves; Carneiro, Romulo Farias; Barroso-Neto, Ito Liberato; Silva, Suzete Roberta; Pereira-Junior, Francisco Nascimento; Nagano, Celso Shiniti; Nascimento, Kyria Santiago; Teixeira, Edson Holanda; Saker-Sampaio, Silvana; Sousa Cavada, Benildo; Sampaio, Alexandre Holanda

    2013-01-01

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

  19. Microencapsulation of lectin anti-cancer agent and controlled release by alginate beads, biosafety approach.

    Science.gov (United States)

    El-Aassar, M R; Hafez, Elsayed E; El-Deeb, Nehal M; Fouda, Moustafa M G

    2014-08-01

    Hepatocellular carcinoma (HCC) is considered as one of the most aggressive cancer worldwide. In Egypt, the prevalence of HCC is increasing during last years. Recently, drug-loaded microparticles were used to improve the efficiency of various medical treatments. This study is designed to evaluate the anticancer potentialities of lectins against HCC while hinting to its safety usage. The aim is also extended to encapsulate lectins in alginate microbeads for oral drug delivery purposes. The extracted lectins showed anti-proliferative effect against HCC with a percentage of 60.76% by using its nontoxic dose with an up-regulation of P53 gene expression. Concerning the handling of lectin alginate microbeads for oral drug delivery, the prepared lectin alginate beads were ∼100μm in diameter. The efficiency of the microcapsules was checked by scanning electron microscopy, the SEM showed the change on the alginate beads surface revealing the successful lectin encapsulation. The release of lectins from the microbeads depended on a variety of factors as the microbeads forming carriers and the amount-encapsulated lectins. The Pisum sativum extracted lectins may be considered as a promising agent in controlling HCC and this solid dosage form could be suitable for oral administration complemented with/or without the standard HCC drugs.

  20. Comparative biochemical analysis of lectin and nuclease from Chelidonium majus L.

    Science.gov (United States)

    Fik, E; Dalgalarrondo, M; Haertlé, T; Goździcka-Józefiak, A

    2000-01-01

    It has been recently recognized that lectins exhibit other activities besides hemagglutination. Previously we have found that purified lectin from Chelidonium majus showed DNase activity (Fik, Goździcka-Józefiak & Kedzia, 1995, Herba Polon. 41, 84-95). Comparison of lectin and DNase from the sap from leaves and roots of Chelidonium majus proved that both these compounds are composed of 24 kDa monomer subunits which have an identical N-terminal sequence but differ in amino-acid composition and degree of glycosylation. Possible interrelationship between lectin and DNase is discussed.

  1. Characterization of a new lectin involved in the protoplast regeneration of Bryopsis hypnoides

    Institute of Scientific and Technical Information of China (English)

    NIU Jianfeng; WANG Guangce; L(U) Fang; ZHOU Baicheng; PENG Guang

    2009-01-01

    A group of coenocytic marine algae differs from higher plants, whose totipotency depends on an intact cell (or protoplast). Instead, this alga is able to aggregate its extruded protoplasm in sea water and generate new mature individuals. It is thought that lectins play a key role in the aggregation process. We purified a lectin associated with the aggregation of cell organelles in Bryopsis hypnoides. The lectin was ca. 27 kDa with a pI between pH 5 and pH 6. The absence of carbohydrate suggested that the lectin was not a glycoprotein. The hemagglutinating activity (HA) of the lectin was not dependent on the presence of divalent cations and was inhibited by N-Acetylgalactosamine, N-Acetylglucosamine, and the glycoprotein bovine submaxillary mucin. The lectin preferentially agglutinated Gram-negative bacterium. The HA of this lectin was stable between pH 4 to pH 10. Cell organelles outside the cytoplasm were agglutinated by the addition of lectin solution (0.5 mg ml-1). Our results suggest that the regeneration of B. hypnoides is mediated by this lectin. We also demonstrated that the formation of cell organelle aggregates was inhibited by nigericin in natural seawater (pH 8.0). Given that nigericin dissipates proton gradients across the membrane, we hypothesize that the aggregation of cell organelles was proton-gradient dependent.

  2. A simple fibril and lectin model for cyst walls of Entamoeba and perhaps Giardia.

    Science.gov (United States)

    Samuelson, John; Robbins, Phillips

    2011-01-01

    Cyst walls of Entamoeba and Giardia protect them from environmental insults, stomach acids, and intestinal proteases. Each cyst wall contains a sugar homopolymer: chitin in Entamoeba and a unique N-acetylgalactosamine (GalNAc) homopolymer in Giardia. Entamoeba cyst wall proteins include Jacob lectins (carbohydrate-binding proteins) that crosslink chitin, chitinases that degrade chitin, and Jessie lectins that make walls impermeable. Giardia cyst wall proteins are also lectins that bind fibrils of the GalNAc homopolymer. Although many of the details remain to be determined for the cyst wall of Giardia, current data suggest a relatively simple fibril and lectin model for the Entamoeba cyst wall.

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

    Directory of Open Access Journals (Sweden)

    ANTÔNIA S. DE OLIVEIRA

    2017-08-01

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

  4. Prevention of intestinal amebiasis by vaccination with the Entamoeba histolytica Gal/GalNac lectin.

    Science.gov (United States)

    Houpt, Eric; Barroso, Lisa; Lockhart, Lauren; Wright, Rhonda; Cramer, Carole; Lyerly, David; Petri, William A

    2004-01-26

    Prevention of intestinal infection by Entamoeba histolytica would block both invasive disease and parasite transmission. The amebic Gal/GalNAc lectin mediates parasite adherence to the colonic surface and fecal anti-lectin IgA is associated with protection from intestinal reinfection in children. We tested if vaccination with the E. histolytica Gal/GalNAc lectin could prevent cecal infection in a C3H mouse model of amebic colitis. Two trials using native lectin purified from the parasite and two trials using a 64 kDa recombinant fragment ("LecA") were performed with a combined intranasal and intraperitoneal immunization regimen using cholera toxin and Freund's adjuvants, respectively. Two weeks after immunization mice were challenged intracecally with trophozoites, and 4-12 weeks after challenge mice were sacrificed for histopathologic evaluation of infection. Vaccination prevented intestinal infection with efficacies of 84 and 100% in the two native lectin trials and 91 and 34% in the two LecA trials. Mice with detectable pre-challenge fecal anti-lectin IgA responses were significantly more resistant to infection than mice without fecal anti-lectin IgA responses. These results show for the first time that immunization with the Gal/GalNAc lectin can prevent intestinal amebiasis in mice and suggest a protective role for fecal anti-lectin IgA in vivo.

  5. Purification, partial characterization and antimicrobial activity of Lectin from Chenopodium Quinoa seeds

    OpenAIRE

    POMPEU,Dávia Guimarães; Marcelo Augusto MATTIOLI; Ribeiro, Rosy Iara Maciel de Azambuja; Gonçalves,Daniel Bonoto; MAGALHÃES,Juliana Teixeira de; Marangoni, Sérgio; Silva,José Antônio da; Paulo Afonso GRANJEIRO

    2015-01-01

    Abstract A novel lectin was isolated from the seeds of Chenopodium quinoa. To achieve this end, the crude extract from the quinoa was submitted to two purification steps, Sephadex G50 and Mono Q. The hemagglutinating activity showed that this lectin agglutinates human erythrocytes. Its activity is inhibited by glucose and mannose, and remained stable under a wide range of pH levels and temperatures. The quinoa lectin was found to be a heterodimeric lectin of approximately 60 kDa, consisting o...

  6. A simple fibril and lectin model for cyst walls of Entamoeba and perhaps Giardia

    Science.gov (United States)

    Samuelson, John; Robbins, Phillips

    2010-01-01

    Cyst walls of Entamoeba and Giardia protect them from environmental insults, stomach acids, and intestinal proteases. Each cyst wall contains a sugar homopolymer: chitin in Entamoeba and a unique N-acetylgalactosamine (GalNAc) homopolymer in Giardia. Entamoeba cyst wall proteins include Jacob lectins (carbohydrate-binding proteins) that cross-link chitin, chitinases that degrade chitin, and Jessie lectins that make walls impermeable. Giardia cyst wall proteins are also lectins that bind fibrils of the GalNAc homopolymer. While many of the details remain to be determined for the Giardia cyst wall, current data suggests a relatively simple fibril and lectin model for the Entamoeba cyst wall. PMID:20934911

  7. Labeling of lectin receptors during the cell cycle.

    Science.gov (United States)

    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.

  8. Ganoderma lucidum: a source for novel bioactive lectin.

    Science.gov (United States)

    U Girjal, Vinay; Neelagund, Shivayogeeswar; Krishnappa, Madappa

    2011-11-01

    Ganoderma lucidum is known for its high medicinal value, clinically used in treatment for various diseases. We have selected this mushroom for isolation of novel bioactive lectin. The isolation procedure comprised of ion-exchange chromatography on DEAE- cellulose and affinity chromatography on Affi-gel blue gel. Purified lectin was monomer with a molecular mass of 15 kDa, determined by SDS-PAGE, Gel filtration, MALDI-ToF. It showed hemagglutinating activity against both human and animal erythrocytes. The hemagglutination activity was not inhibited by simple sugars but inhibited by glycoproteins. The activity was maximal at pH range 4.0-9.0 and at temperature up to 60° C. The hemagglutination activity was stable even in the presence of 10mM EDTA and other divalent metal cations such as CaCl2, MgCl2, ZnCl2, and MnCl2. Lectin was shown antifungal activity against following pathogens Fusarium oxysporium, Penicillium chrysogenum, Aspergillus Niger, Colletotrichum musae, Botrytis cinerea, Trichophyton rubrum, Trichophyton tonsurans, Trichophyton interdigitale, Epidermophyton floccosum and Microsporum canis.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  11. Structure of mannose-specific snowdrop (Galanthus nivalis) lectin is representative of a new plant lectin family.

    Science.gov (United States)

    Hester, G; Kaku, H; Goldstein, I J; Wright, C S

    1995-06-01

    Tetrameric Galanthus nivalis agglutinin (50,000 M(r)) belongs to a super-family of alpha-D-mannose-specific plant bulb lectins known to be potent inhibitors of retroviruses. The 2.3 A crystal structure of this lectin complexed with methyl alpha-D-mannose reveals a novel three-fold symmetric beta-sheet polypeptide fold. Three antiparallel four-stranded beta-sheets, each with a conserved mannose-binding site, are arranged as a 12-stranded beta-barrel. The tetramer displays 222 symmetry. Pairs of monomers form stable dimers through C-terminal strand exchange. The so formed hybrid beta-sheets are the sites for high affinity mannose binding in the dimer interface. Occupancy observed at corresponding sites in other beta-sheets suggests a potential for twelve sites per tetramer.

  12. Polymorphisms in the Mannose-Binding Lectin Gene are Associated with Defective Mannose-Binding Lectin Functional Activity in Crohn's Disease Patients.

    Science.gov (United States)

    Choteau, Laura; Vasseur, Francis; Lepretre, Frederic; Figeac, Martin; Gower-Rousseau, Corine; Dubuquoy, Laurent; Poulain, Daniel; Colombel, Jean-Frederic; Sendid, Boualem; Jawhara, Samir

    2016-01-01

    Mannose-binding lectin, together with mannose-associated serine proteases, activates the lectin pathway of the complement system and subsequent inflammatory mechanisms. An association between mannose-binding lectin deficiency and anti-Saccharomyces cerevisiae antibody levels is observed in Crohn's disease and this deficiency is frequently associated with a severe Crohn's disease phenotype. In the present study, we assessed the relationship between serum concentrations of mannose-binding lectin, mannose-binding lectin functional activity, MBL2 and NOD2 polymorphisms, anti-S. cerevisiae antibody levels and clinical Crohn's disease phenotype in 69 Crohn's disease patients and 30 age- and sex-matched healthy controls. The results show that the MBL2 variant rs5030737 at codon 52 was associated with a low level of mannose-binding lectin and impaired mannose-binding lectin-mannose-associated serine protease (MBL-MASP) functional activity in Crohn's disease patients. This MBL2 variant was also associated with a higher level of anti-S. cerevisiae antibodies. In addition, the NOD2 variant rs2066844, which is associated with susceptibility to Crohn's disease, was significantly correlated with an impairment in MBL-MASP functional activity. These results provide evidence that Crohn's disease patients have an impairment in MBL-MASP functional activity and that this defect is associated with MBL2 and NOD2 variants.

  13. Functional characterization of mannose-binding lectin in zebrafish: implication for a lectin-dependent complement system in early embryos.

    Science.gov (United States)

    Yang, Lili; Bu, Lingzhen; Sun, Weiwei; Hu, Lili; Zhang, Shicui

    2014-10-01

    The lectin pathway involves recognition of pathogen-associated molecular patterns by mannose-binding lectin (MBL), and the subsequent activation of associated enzymes, termed MBL-associated serine proteases (MASPs). In this study, we demonstrate that the transcript of MBL gene is present in the early embryo of zebrafish, and MBL protein is also present in the embryo. In addition, we show that recombinant zebrafish MBL was able to bind the Gram-negative bacterium Escherichia coli and the Gram-positive bacterium Staphylococcus aureus, and rMBL was able to promote the phagocytosis of E. coli and S. aureus by macrophages, indicating that like mammalian MBL, zebrafish MBL performs a dual function in both pattern recognition and opsonization. Importantly, we show that microinjection of anti-MBL antibody into the early developing embryos resulted in a significantly increased mortality in the embryos challenged with Aeromonas hydrophila (pathogenic to zebrafish); and injection of rMBL into the embryos (resulting in increase in MBL in the embryo) markedly promoted their resistance to A. hydrophila; and this promoted bacterial resistance was significantly reduced by the co-injection of anti-MBL antibody with rMBL but not by the injection of anti-actin antibody with rMBL. These suggest that the lectin pathway may be already functional in the early embryos in zebrafish before their immune system is fully matured, protecting the developing embryos from microbial infection. This work provides a new angle to understand the immune role of the lectin pathway in early development of animals.

  14. The in vivo synthesis and accumulation of lectin in developing seeds of black gram (Vigna mungo L. Hepper).

    Science.gov (United States)

    Suseelan, K N; Mitra, R; Bhatia, C R; Gopalakrishna, T

    2004-01-01

    Black gram (Vigna mungo L. Hepper) seed contains two D-galactose-specific lectin species, BGL-I and BGL-II, identified on the basis of elution from ion exchange column and immunochemical cross-reactivity. BGL-I consisted of two monomeric lectins, BGL-I-1 and BGL-1-2, of relative molecular weights 94 and 89 kDa, respectively. BGL-II is another monomeric lectin with a molecular weight of 83 kDa. The in vivo synthesis studies using pulse-chase experiment showed that BGL-II lectin was synthesized as early as 14 days after flowering (DAF). The 94-kDa BGL-I-1 lectin was synthesized around 17 DAF. There was no cotranslational or posttranslational modification of the lectin proteins. The amount of lectin in developing seeds was determined by radial immunodiffusion assay technique. The maximum amount of lectin per seed was found at 28 DAF.

  15. Regulation of adherence and virulence by the Entamoeba histolytica lectin cytoplasmic domain, which contains a beta2 integrin motif.

    Science.gov (United States)

    Vines, R R; Ramakrishnan, G; Rogers, J B; Lockhart, L A; Mann, B J; Petri, W A

    1998-08-01

    Killing of human cells by the parasite Entamoeba histolytica requires adherence via an amebic cell surface lectin. Lectin activity in the parasite is regulated by inside-out signaling. The lectin cytoplasmic domain has sequence identity with a region of the beta2 integrin cytoplasmic tail implicated in regulation of integrin-mediated adhesion. Intracellular expression of a fusion protein containing the cytoplasmic domain of the lectin has a dominant negative effect on extracellular lectin-mediated cell adherence. Mutation of the integrin-like sequence abrogates the dominant negative effect. Amebae expressing the dominant negative mutant are less virulent in an animal model of amebiasis. These results suggest that inside-out signaling via the lectin cytoplasmic domain may control the extracellular adhesive activity of the amebic lectin and provide in vivo demonstration of the lectin's role in virulence.

  16. Biosynthesis, primary structure and molecular cloning of snowdrop (Galanthus nivalis L.) lectin.

    Science.gov (United States)

    Van Damme, E J; Kaku, H; Perini, F; Goldstein, I J; Peeters, B; Yagi, F; Decock, B; Peumans, W J

    1991-11-15

    Poly(A)-rich RNA isolated from ripening ovaries of snowdrop (Galanthus nivalis L.) yielded a single 17-kDa lectin polypeptide upon translation in a wheat-germ cell-free system. This lectin was purified by affinity chromatography. Translation of the same RNA in Xenopus leavis oocytes revealed a lectin polypeptide which was about 2 kDa smaller than the in vitro synthesized precursor, suggesting that the oocyte system had removed a 2-kDa signal peptide. A second post-translational processing step was likely to be involved since both the in vivo precursor and the Xenopus translation products were about 2 kDa larger than the mature lectin polypeptide. This hypothesis was confirmed by the structural analysis of the amino acid sequence of the mature protein and the cloned mRNA. Edman degradation and carboxypeptidase Y digestion of the mature protein, and structural analysis of the peptides obtained after chemical cleavage and modification, allowed determination of the complete 105 amino acid sequence of the snowdrop lectin polypeptide. Comparison of this sequence with the deduced amino acid sequence of a lectin cDNA clone revealed that besides the mature lectin polypeptide, the lectin mRNA also encoded a 23 amino acid signal-sequence and a C-terminal extension of 29 amino acids, which confirms the results from in vitro translation experiments.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

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

  18. Serine protease immunohistochemistry and lectin histochemistry in the small intestine of weaned and unweaned pigs

    DEFF Research Database (Denmark)

    Brown, P J; Poulsen, Steen Seier; Wells, M

    1991-01-01

    The distribution of goblet cells containing serine protease and of those binding the lectin Ulex europaeus agglutinin-1 (UEA-1) in the pig small intestine is altered during the period after weaning. Goblet cells exhibiting binding of other lectins were not altered. These alterations and other...

  19. Antinociceptive activity of lectins from Diocleinae seeds on acetic acid-induced writhing test in mice.

    Science.gov (United States)

    Holanda, Fernanda R; Coelho-de-Sousa, Andrelina N; Assreuy, Ana M S; Leal-Cardoso, José Henrique; Pires, Alana F; do Nascimento, Kyria S; Teixeira, Cícero S; Cavada, Benildo S; Santos, Cláudia F

    2009-01-01

    Diocleinae lectins administered per oral route in mice inhibited the abdominal constrictions induced by acetic acid. The percentage of the lectins antinociception varied from 61% for Canavalia grandiflora (ConGf) to 20% for Dioclea violacea. ConGf inhibited contortions at all doses tested but not in a dose-dependent manner, involving carbohydrate recognition.

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

    Directory of Open Access Journals (Sweden)

    Arishya Sharma

    2009-01-01

    Full Text Available 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-12-03

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

  2. Preparation and biological properties of a melibiose binding lectin from Bauhinia variegata seeds.

    Science.gov (United States)

    Lin, Peng; Ng, Tzi Bun

    2008-11-26

    A dimeric 64-kDa melibiose-binding lectin was isolated from the seeds of Bauhinia variegata. The isolation procedure comprised affinity chromatography on Affi-gel blue gel, ion exchange chromatography on Mono Q, and gel filtration on Superdex 75. The lectin was adsorbed on the first two chromatographic media. Its hemagglutinating activity was stable after 30-min exposure to temperatures up to 70 degrees C. Since lectins may demonstrate biological activities such as antiproliferative, immunomodulatory, antifungal, antiviral, and HIV-1 reverse transcriptase inhibitory activities, the isolated lectin was tested for these activities. It was found that the lectin inhibited proliferation in hepatoma HepG2 cells and breast cancer MCF7 cells with an IC(50) of 1.4 microM and 0.18 microM, respectively. HIV-1 reverse transcriptase activity was inhibited with an IC(50) of 1.02 microM. The lectin and concanavalin A (Con A) evoked maximal mitogenic response from mouse splenocytes at similar concentrations, but the maximal response to B. variegata lectin was only 1/5 of that induced by Con A in magnitude. B. variegata lectin was devoid of antifungal activity.

  3. Bitter-sweet symphony: glycan-lectin interactions in virus biology

    NARCIS (Netherlands)

    van Breedam, W.; Pöhlmann, S.; Favoreel, H.W.; de Groot, R.J.|info:eu-repo/dai/nl/07401000X; Nauwynck, H.J.

    2014-01-01

    Glycans are carbohydrate modifications typically found on proteins or lipids, and can act as ligands for glycan-binding proteins called lectins. Glycans and lectins play crucial roles in the function of cells and organs, and in the immune system of animals and humans. Viral pathogens use glycans and

  4. Antinociceptive and Anti-inflammatory Activities of the Lectin from Marine Red Alga Solieria filiformis.

    Science.gov (United States)

    Abreu, Ticiana Monteiro; Ribeiro, Natássia Albuquerque; Chaves, Hellíada Vasconcelos; Jorge, Roberta Jeane Bezerra; Bezerra, Mirna Marques; Monteiro, Helena Serra Azul; Vasconcelos, Ilka Maria; Mota, Érika Freitas; Benevides, Norma Maria Barros

    2016-05-01

    Lectins are proteins that bind to specific mono- or oligosaccharides. This study aimed to evaluate the antinociceptive and anti-inflammatory effects of the lectin from the red marine alga Solieria filiformis. The animals (n = 6) were pretreated with S. filiformis lectin 30 min before they were given the nociceptive or inflammatory stimulus. The antinociceptive activity was evaluated in Swiss mice using the abdominal writhing, formalin, and hot plate tests. The anti-inflammatory properties were evaluated in Wistar rats using carrageenan-induced peritonitis and paw edema induced by different phlogistic agents. The S. filiformis lectin toxicity was assayed through its application in mice (7 days). S. filiformis lectin significantly reduced the number of abdominal writhings and reduced the paw licking time in the second phase of the formalin test (p  0.05). Furthermore, S. filiformis lectin reduced neutrophil migration in a peritonitis model and reduced paw edema induced by carrageenan, dextran, and serotonin (p < 0.05). Additionally, the administration of S. filiformis lectin resulted in no signs of systemic damage. Thus, S. filiformis lectin appears to have important antinociceptive and anti-inflammatory activities and could represent a potential therapeutic agent for future studies. Georg Thieme Verlag KG Stuttgart · New York.

  5. Mannose-binding lectin variant alleles and the risk of arterial thrombosis in systemic lupus erythematosus

    DEFF Research Database (Denmark)

    Øhlenschlaeger, Tommy; Garred, Peter; Madsen, Hans O

    2004-01-01

    Cardiovascular disease is an important complication in patients with systemic lupus erythematosus (SLE). Variant alleles of the mannose-binding lectin gene are associated with SLE as well as with severe atherosclerosis. We determined whether mannose-binding lectin variant alleles were associated...

  6. Mannose-binding lectin polymorphisms and susceptibility to infection in systemic lupus erythematosus

    DEFF Research Database (Denmark)

    Garred, P; Madsen, H O; Halberg, P

    1999-01-01

    To determine whether variant alleles in the coding portion of the mannose-binding lectin (MBL) gene are associated with increased susceptibility to systemic lupus erythematosus (SLE) and concomitant infections.......To determine whether variant alleles in the coding portion of the mannose-binding lectin (MBL) gene are associated with increased susceptibility to systemic lupus erythematosus (SLE) and concomitant infections....

  7. The Roles of Direct Recognition by Animal Lectins in Antiviral Immunity and Viral Pathogenesis

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2015-01-01

    Full Text Available Lectins are a group of proteins with carbohydrate recognition activity. Lectins are categorized into many families based on their different cellular locations as well as their specificities for a variety of carbohydrate structures due to the features of their carbohydrate recognition domain (CRD modules. Many studies have indicated that the direct recognition of particular oligosaccharides on viral components by lectins is important for interactions between hosts and viruses. Herein, we aim to globally review the roles of this recognition by animal lectins in antiviral immune responses and viral pathogenesis. The different classes of mammalian lectins can either recognize carbohydrates to activate host immunity for viral elimination or can exploit those carbohydrates as susceptibility factors to facilitate viral entry, replication or assembly. Additionally, some arthropod C-type lectins were recently identified as key susceptibility factors that directly interact with multiple viruses and then facilitate infection. Summarization of the pleiotropic roles of direct viral recognition by animal lectins will benefit our understanding of host-virus interactions and could provide insight into the role of lectins in antiviral drug and vaccine development.

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

    Directory of Open Access Journals (Sweden)

    Lander Bauters

    2017-01-01

    Full Text Available 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.

  9. Virus-Induced Gene Silencing in the Culinary Ginger (Zingiber officinale): An Effective Mechanism for Down-Regulating Gene Expression in Tropical Monocots

    Institute of Scientific and Technical Information of China (English)

    Tanya Renner; Jennifer Bragga; Heather E. Driscoll; Juliana Cho; Andrew O. Jackson; Chelsea D. Specht

    2009-01-01

    Virus-induced gene silencing (VIGS) has been shown to be effective for transient knockdown of gene expres-sion in plants to analyze the effects of specific genes in development and stress-related responses. VlGS is well established for studies of model systems and crops within the Solanaceae, Brassicaceae, Leguminaceae, and Poaceae, but only recently has been applied to plants residing outside these families. Here, we have demonstrated that barley stripe mosaic virus (BSMV) can infect two species within the Zingiberaceae, and that BSMV-VlGS can be applied to specifically down-regulate phytoene desaturase in the culinary ginger Zingiber officinale. These results suggest that extension of BSMV-VIGS to monocots other than cereals has the potential for directed genetic analyses of many important temperate and tropical crop species.

  10. Azospirillum lectin – induced changes in the content of nitric oxide in wheat seedling roots

    Directory of Open Access Journals (Sweden)

    Alen’kina S.A.

    2010-11-01

    Full Text Available The lectin of Azospirillum brasilense Sp7 at 40 μg ml-1 elicited two peaks of induction of nitric oxide synthesis in the roots of wheat seedlings after 3 and 26 h of coincubation. The lectin of A. brasilense Sp7.2.3, a mutant defective in lectin activity, produced the same effect, but the activation of nitric oxide synthesis in the roots was less in the case of 26-h incubation. Exposure to the lectins for 3 h increased citrulline synthesis in the plant cell to the same extent. This finding indicated that the Azospirillum lectins activate nitric oxide production through the NO signal system of plants, thereby acting as inducers of adaptation processes in the roots of wheat seedlings.

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

    Science.gov (United States)

    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.

  12. Discovery of Linear Cyclotides in Monocot Plant Panicum laxum of Poaceae Family Provides New Insights into Evolution and Distribution of Cyclotides in Plants*

    Science.gov (United States)

    Nguyen, Giang Kien Truc; Lian, Yilong; Pang, Edmund Weng Hou; Nguyen, Phuong Quoc Thuc; Tran, Tuan Dinh; Tam, James P.

    2013-01-01

    Cyclotides are disulfide-rich macrocyclic peptides that display a wide range of bioactivities and represent an important group of plant defense peptide biologics. A few linear variants of cyclotides have recently been identified. They share a high sequence homology with cyclotides but are biosynthetically unable to cyclize from their precursors. All hitherto reported cyclotides and their acyclic variants were isolated from dicot plants of the Rubiaceae, Violaceae, Cucurbitaceae, and recently the Fabaceae and Solanaceae families. Although several cyclotide-like genes in the Poaceae family were known from the data mining of the National Center for Biotechnology Information (NCBI) nucleotide database, their expression at the protein level has yet to be proven. Here, we report the discovery and characterization of nine novel linear cyclotides, designated as panitides L1–9, from the Panicum laxum of the Poaceae family and provide the first evidence of linear cyclotides at the protein level in a monocot plant. Disulfide mapping of panitide L3 showed that it possesses a cystine knot arrangement similar to cyclotides. Several panitides were shown to be active against Escherichia coli and cytotoxic to HeLa cells. They also displayed a high stability against heat and proteolytic degradation. Oxidative folding of the disulfide-reduced panitide L1 showed that it can fold efficiently into its native form. The presence of linear cyclotides in both dicots and monocots suggests their ancient origin and existence before the divergence of these two groups of flowering plants. Moreover, the Poaceae family contains many important food crops, and our discovery may open up new avenues of research using cyclotides and their acyclic variants in crop protection. PMID:23195955

  13. Lack of S-RNase-Based Gametophytic Self-Incompatibility in Orchids Suggests That This System Evolved after the Monocot-Eudicot Split

    Directory of Open Access Journals (Sweden)

    Shan-Ce Niu

    2017-06-01

    Full Text Available Self-incompatibility (SI is found in approximately 40% of flowering plant species and at least 100 families. Although orchids belong to the largest angiosperm family, only 10% of orchid species present SI and have gametophytic SI (GSI. Furthermore, a majority (72% of Dendrobium species, which constitute one of the largest Orchidaceae genera, show SI and have GSI. However, nothing is known about the molecular mechanism of GSI. The S-determinants of GSI have been well characterized at the molecular level in Solanaceae, Rosaceae, and Plantaginaceae, which use an S-ribonuclease (S-RNase-based system. Here, we investigate the hypothesis that Orchidaceae uses a similar S-RNase to those described in Rosaceae, Solanaceae, and Plantaginaceae SI species. In this study, two SI species (Dendrobium longicornu and D. chrysanthum were identified using fluorescence microscopy. Then, the S-RNase- and SLF-interacting SKP1-like1 (SSK1-like genes present in their transcriptomes and the genomes of Phalaenopsis equestris, D. catenatum, Vanilla shenzhenica, and Apostasia shenzhenica were investigated. Sequence, phylogenetic, and tissue-specific expression analyses revealed that none of the genes identified was an S-determinant, suggesting that Orchidaceae might have a novel SI mechanism. The results also suggested that RNase-based GSI might have evolved after the split of monocotyledons (monocots and dicotyledons (dicots but before the split of Asteridae and Rosidae. This is also the first study to investigate S-RNase-based GSI in monocots. However, studies on gene identification, differential expression, and segregation analyses in controlled crosses are needed to further evaluate the genes with high expression levels in GSI tissues.

  14. Phylogenetic and comparative gene expression analysis of barley (Hordeum vulgare WRKY transcription factor family reveals putatively retained functions between monocots and dicots

    Directory of Open Access Journals (Sweden)

    Jansson Christer

    2008-04-01

    Full Text Available Abstract Background WRKY proteins belong to the WRKY-GCM1 superfamily of zinc finger transcription factors that have been subject to a large plant-specific diversification. For the cereal crop barley (Hordeum vulgare, three different WRKY proteins have been characterized so far as regulators in sucrose signaling, pathogen defense, and in response to cold and drought. However, their phylogenetic relationship remained unresolved. Results In this study, we used available sequence information to identify a minimum number of 45 barley WRKY transcription factor (HvWRKY genes. According to their structural features, the HvWRKY factors were classified into the previously defined polyphyletic WRKY subgroups 1 to 3. Furthermore, we could assign putative orthologs of the HvWRKY proteins in Arabidopsis and rice. While in most cases clades of orthologous proteins were formed within each group or subgroup, other clades were composed of paralogous proteins for the grasses and Arabidopsis only, which is indicative of specific gene radiation events. To gain insight into their putative functions, we examined expression profiles of WRKY genes from publicly available microarray data resources and found group specific expression patterns. While putative orthologs of the HvWRKY transcription factors have been inferred from phylogenetic sequence analysis, we performed a comparative expression analysis of WRKY genes in Arabidopsis and barley. Indeed, highly correlative expression profiles were found between some of the putative orthologs. Conclusion HvWRKY genes have not only undergone radiation in monocot or dicot species, but exhibit evolutionary traits specific to grasses. HvWRKY proteins exhibited not only sequence similarities between orthologs with Arabidopsis, but also relatedness in their expression patterns. This correlative expression is indicative for a putative conserved function of related WRKY proteins in monocot and dicot species.

  15. [Lectin histochemistry of the Bufo marinus L. toad tongue].

    Science.gov (United States)

    González Elorriaga, M; Jaloveckas, D; Salazar de Candelle, M

    1995-01-01

    Lectin histochemistry at light microscope level was used in the tongue of the cane toad Bufo marinus to determine the distribution of sugar residues in glycoconjugates (GCs) previously localized and characterized by conventional histochemical techniques. Five horseradish-peroxidase (HRP) labeled-lectins, namely Con A, PNA, SBA, UEA-1 and WGS were used. Additionally, neuraminidase (N) treated sections before the staining procedures were used in order to dilucidate the presence of terminal sialic acid (SA). Sugar residues in GCs of the taste organ (TO) associated mucous cells stained more intensely with WGA than with Con A and UEA-1. All the sensory cells reacted with Con A and WGA but one type of them were characteristically labeled by UEA-1. The glycocalix (gc) of the TOs resulted intensely stained with Con A and with WGA and UEA-1 before and after N treatment. The GCs in the mucous-supporting cells of dorsal mucosae filiform papillae and folds reacted intensely with WGA and weakly with Con A. The ciliated cells (cic) were intense and characteristically stained with UEA-1 and WGA and moderately with Con A. The gc reacted more intensely with WGA than with Con A. Dorsal mucosae glands secretory cells mucins were characteristically stained with PNA, SBA and WGA besides Con A, while glandular ciliated cells showed the same staining pattern as in the filiform papillae. In the ventral mucosa all epithelium cells resulted stained with WGA and Con A, while differentiated goblet cells only reacted as well with UEA-1 and PNA before and after neuraminidase treatment. Unexpectedly, ciliated ventral mucosae cells did not react with UEA-1 but only with WGA and Con A. The results have shown that lectin histochemistry is an interesting tool to characterize similarities and differences in the lingual GCs sugar residues composition and distribution, particularly those located in epithelial cells.

  16. Re-examining the proposed lectin properties of IL-2.

    Science.gov (United States)

    Papalia, Giuseppe A; Rini, James M

    2008-03-01

    Early work examining the interactions of IL-2 and the urinary glycoprotein uromodulin led to the suggestion that IL-2 was a lectin with specificity for high-mannose and mannan ligands. Subsequent studies have attributed various roles to these properties, some critical to the cell proliferative activity of IL-2. In an attempt to verify the reported interaction between IL-2 and mannose containing carbohydrate ligands we studied two biologically active forms of IL-2 using various techniques including affinity chromatography, equilibrium dialysis, and NMR methods. Despite previous reports we have not been able to demonstrate that IL-2 possesses the ability to bind carbohydrate.

  17. Mannan-binding lectin in astma and allergy

    DEFF Research Database (Denmark)

    Kaur, S.; Thiel, Steffen; Sarma, P.U.

    2006-01-01

    Mannan-binding lectin (MBL) is a vital and versatile component of innate immunity. It is present in serum and may bind to a plethora of microbial pathogens and mediate opsonization of these by complement-dependent and/or independent mechanisms. Low-MBL levels in serum, attributed to certain genetic...... polymorphisms, constitute a major factor predisposing to several infectious diseases. However, recent studies propose that MBL extends beyond its classic role as a first-line host-defense molecule to a modulator of inflammation. In this review, we summarize and explore this potential and a possible novel role...

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

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    Irena Lorenc-Kubis

    2014-02-01

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

  19. Gal/GalNAc specific multiple lectins in marine bivalve Anadara granosa.

    Science.gov (United States)

    Adhya, Mausumi; Singha, Biswajit

    2016-03-01

    Complete lectin mapping of molluscs with their diversified recognition pattern and possible role in lectin-carbohydrate interaction based immune response triggering need much attention. In this communication, Gal/GalNAc specific three lectins AGL-IA (Anadara granosa lectin-IA), AGL-IB (A. granosa lectin-IB) and AGL-IV (A. granosa lectin-IV) and a lectin having hemolytic activity AGL-III (A. granosa lectin-III) were purified from the plasma of A. granosa bivalve by a combination of gel filtration and affinity chromatography. AGL-IA and IB were oligomeric lectins whereas, AGL-III and IV were monomeric. The molecular weight of AGL-IA, IB, III and IV were 375, 260, 45 and 33 kDa respectively. AGL-IA and IV agglutinated both rabbit and pronase treated human erythrocytes, whereas AGL-IB agglutinated only rabbit erythrocytes. AGL-III was found to agglutinate rabbit erythrocytes, however, it caused hemolysis of pronase treated human erythrocytes. The activity of all four lectins was calcium dependent and maximum at a pH range 7-8. Apart from Gal/GalNAc specific, the four lectins showed substantial differences in their carbohydrate recognition pattern. Moreover, there was a difference in the carbohydrate specificity between AGL-III and other three lectins (AGL-IA, AGL-IB and AGL-IV) towards polyvalent glycotope. On the one hand, 'cluster glycoside effect' i.e., an enhancement of the activity of a multivalent ligand, was observed for carbohydrate specificities of AGL-IA, AGL-IB, AGL-IV. On the other hand, the effect of multivalent ligands on the carbohydrate specificity of AGL-III was opposite of cluster glycoside effect. The affinity of AGL-IA, AGL-IB and AGL-IV for ligands can be ranked as follows: glycoproteins > polysaccharide > oligosaccharides and monosaccharides. However, Gal related monosaccharides were the best inhibitors of AGL-III and the inhibitory activity decreased gradually in the following order: monosaccharide > disaccharide > polysaccharide. Thus, the

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    complement pathway regulator MAP-1. Furthermore, we found that complex formation between recombinant collectin-11 and recombinant MASP-2 on Candida albicans leads to deposition of C4b. Native collectin-11 in serum mediated complement activation and deposition of C4b and C3b, and formation of the terminal...... complement complex on C. albicans. Moreover, spiking collectin-11-depleted serum, which did not mediate complement activation, with recombinant collectin-11 restored the complement activation capability. These results define collectin-11 as the fifth recognition molecule in the lectin complement pathway...

  1. Carbohydrate specificity of lectin, purified from the fruiting bodies of Mycena pura /Fr./ Kumm. and its use in histochemical investigation

    Directory of Open Access Journals (Sweden)

    Ambarova N. O.

    2009-12-01

    Full Text Available Aim. The purpose of this investigation was to research carbohydrate specificity of a new lectin from fruiting body of Mycena pura and possibilities of its application in histochemical studies. Methods. The lectin has been purified by affinity chromatography on «îvomucine». The lectin carbohydrate specificity has been determined by a reaction of inhibiting haemagglutination by haptens. Histological materials were fixed in 4 % neutral formalin solution. Alkaline phosphatase was revealed in the cryostat unfixed microscopical sections. Results. The lectin yield from fresh fruit bodies of raw material was 9 mg/kg. Mol. mass of the lectin is 40 kDa. The lectin poorly interacted with D-glucose and D-mannose in contrast to lectins from Pisum sativum and Leucojum vernum. The peculiarity of this lectin is its strong interaction with alkaline phosphatase, the highest among twenty tested lectins. However, the receptors for Mycena lectin binding in mammalian tissues are not limited by this enzyme being presented also by glycoconjugates of another structure, as it was shown for fetus calf small intestine and kidney of rat. Conclusions. An important role in the lectin interaction with glycoproteins probably belongs to the disaccharide links of GlcNAcb(1-2Mana(1-6 or GlcNAcb(1- 2Mana(1-2, which not necessarily are terminal

  2. Anti-Neuroblastoma Properties of a Recombinant Sunflower Lectin

    Science.gov (United States)

    Pinedo, Marcela; Genoula, Melanie; Silveyra, María Ximena; De Oliveira Carvalho, André; Regente, Mariana; Del Río, Marianela; Ribeiro Soares, Júlia; Moreira Gomes, Valdirene; De La Canal, Laura

    2017-01-01

    According to their sugar recognition specificity, plant lectins are proposed as bioactive proteins with potential in cancer treatment and diagnosis. Helja is a mannose-specific jacalin-like lectin from sunflower which was shown to inhibit the growth of certain fungi. Here, we report its recombinant expression in a prokaryotic system and its activity in neurobalstoma cells. Helja coding sequence was fused to the pET-32 EK/LIC, the enterokinase/Ligation-independent cloning vector and a 35 kDa protein was obtained in Escherichia coli representing Helja coupled to thioredoxin (Trx). The identity of this protein was verified using anti-Helja antibodies. This chimera, named Trx-rHelja, was enriched in the soluble bacterial extracts and was purified using Ni+2-Sepharose and d-mannose-agarose chromatography. Trx-rHelja and the enterokinase-released recombinant Helja (rHelja) both displayed toxicity on human SH-SY5Y neuroblastomas. rHelja decreased the viability of these tumor cells by 75% according to the tetrazolium reduction assay, and microscopic analyses revealed that the cell morphology was disturbed. Thus, the stellate cells of the monolayer became spheroids and were isolated. Our results indicate that rHelja is a promising tool for the development of diagnostic or therapeutic methods for neuroblastoma cells, the most common solid tumors in childhood. PMID:28075401

  3. Lectin functionalized quantum dots for recognition of mammary tumors

    Science.gov (United States)

    Santos, Beate S.; de Farias, Patricia M. A.; de Menezes, Frederico D.; de C. Ferreira, Ricardo; Júnior, Severino A.; Figueiredo, Regina C. B. Q.; Beltrão, Eduardo I. C.

    2006-02-01

    In this study we use CdS/Cd(OH) II quantum dots functionalized with concanavalin-A (Con-A) lectin, specific to glucose/mannose residues, to investigate cell alterations regarding carbohydrate profile in human mammary tissues diagnosed as fibroadenoma (benign tumor). These particles were functionalized with glutaraldehyde and Con-A and incubated with tissue sections of normal and to Fibroadenoma, a benign type of mammary tumor. The tissue sections were deparafinized, hydrated in graded alcohol and treated with a solution of Evans Blue in order to avoid autofluorescence. The fluorescence intensity of QD-Con-A stained tissues showed different patterns, which reflect the carbohydrate expression of glucose/mannose in fibroadenoma when compared to the detection of the normal carbohydrate expression. The pattern of unspecific labeling of the tissues with glutaraldehyde functionalized CdS/Cd(OH) II quantum dots is compared to the targeting driven by the Con-A lectin. The preliminary findings reported here support the use of CdS/Cd(OH) II quantum dots as specific probes of cellular alterations and their use in diagnostics.

  4. Anti-Neuroblastoma Properties of a Recombinant Sunflower Lectin

    Directory of Open Access Journals (Sweden)

    Marcela Pinedo

    2017-01-01

    Full Text Available According to their sugar recognition specificity, plant lectins are proposed as bioactive proteins with potential in cancer treatment and diagnosis. Helja is a mannose-specific jacalin-like lectin from sunflower which was shown to inhibit the growth of certain fungi. Here, we report its recombinant expression in a prokaryotic system and its activity in neurobalstoma cells. Helja coding sequence was fused to the pET-32 EK/LIC, the enterokinase/Ligation-independent cloning vector and a 35 kDa protein was obtained in Escherichia coli representing Helja coupled to thioredoxin (Trx. The identity of this protein was verified using anti-Helja antibodies. This chimera, named Trx-rHelja, was enriched in the soluble bacterial extracts and was purified using Ni+2-Sepharose and d-mannose-agarose chromatography. Trx-rHelja and the enterokinase-released recombinant Helja (rHelja both displayed toxicity on human SH-SY5Y neuroblastomas. rHelja decreased the viability of these tumor cells by 75% according to the tetrazolium reduction assay, and microscopic analyses revealed that the cell morphology was disturbed. Thus, the stellate cells of the monolayer became spheroids and were isolated. Our results indicate that rHelja is a promising tool for the development of diagnostic or therapeutic methods for neuroblastoma cells, the most common solid tumors in childhood.

  5. Lectin-mediated drug delivery: the second generation of bioadhesives.

    Science.gov (United States)

    Lehr, C M

    2000-03-01

    This paper reviews some recent developments in the area of bioadhesive drug delivery systems. The area of bioadhesion in drug delivery had started some 20 years ago by using so-called mucoadhesive polymers. Many of these polymers were already used as excipients in pharmaceutical formulations. This has facilitated the development of the first bioadhesive drug products, which are now commercially available. A major disadvantage of the hitherto known mucoadhesives, however, is their non-specificity with respect to the substrate. In particular for gastro-intestinal applications, this may cause some premature inactivation and moreover limits the duration of mucoadhesive bonds to the relatively fast mucus turnover. Nevertheless, for some mucoadhesive polymers other interesting functionalities were discovered, such as their ability to modulate epithelial permeability and to inhibit proteolytic enzymes. In contrast to the mucoadhesive polymers, lectins and some other adhesion molecules specifically recognize receptor-like structures of the cell membrane and therefore bind directly to the epithelial cells themselves ("cytoadhesion") rather than to the mucus gel layer. Furthermore, when bioadhesion is receptor-mediated, it is not only restricted to mere binding, but may subsequently trigger the active transport of large molecules or nanoscalic drug carrier systems by vesicular transport processes (endo-/transcytosis). Rather than only acting as a platform for controlled release systems, the concept of lectin-mediated bioadhesion therefore bears the potential for the controlled delivery of macromolecular biopharmaceuticals at relevant biological barriers, such as the epithelia of the intestinal or respiratory tract.

  6. Nkrp1 Family, from Lectins to Protein Interacting Molecules

    Directory of Open Access Journals (Sweden)

    Daniel Rozbeský

    2015-02-01

    Full Text Available The C-type lectin-like receptors include the Nkrp1 protein family that regulates the activity of natural killer (NK cells. Rat Nkrp1a was reported to bind monosaccharide moieties in a Ca2+-dependent manner in preference order of GalNac > GlcNAc >> Fuc >> Gal > Man. These findings established for rat Nkrp1a have been extrapolated to all additional Nkrp1 receptors and have been supported by numerous studies over the past two decades. However, since 1996 there has been controversy and another article showed lack of interactions with saccharides in 1999. Nevertheless, several high affinity saccharide ligands were synthesized in order to utilize their potential in antitumor therapy. Subsequently, protein ligands were introduced as specific binders for Nkrp1 proteins and three dimensional models of receptor/protein ligand interaction were derived from crystallographic data. Finally, for at least some members of the NK cell C-type lectin-like proteins, the “sweet story” was impaired by two reports in recent years. It has been shown that the rat Nkrp1a and CD69 do not bind saccharide ligands such as GlcNAc, GalNAc, chitotetraose and saccharide derivatives (GlcNAc-PAMAM do not directly and specifically influence cytotoxic activity of NK cells as it was previously described.

  7. Crystallization and crystal manipulation of the Pterocarpus angolensis seed lectin.

    Science.gov (United States)

    Loris, Remy; Garcia-Pino, Abel; Buts, Lieven; Bouckaert, Julie; Beeckmans, Sonia; De Greve, Henri; Wyns, Lode

    2005-06-01

    The Man/Glc-specific legume lectin from the seeds of the African bloodwood tree (Pterocarpus angolensis) was crystallized in the presence of the disaccharide ligand Man(alpha1-3)ManMe. Small crystals initially appeared from a preliminary screen, but proved difficult to reproduce. The initial crystals were used to prepare microseeds, leading to a reproducible crystallization protocol. All attempts to obtain crystals directly of the ligand-free protein or of other carbohydrate complexes failed. However, the Man(alpha1-3)ManMe co-crystals withstand soaking with ten other carbohydrates known to bind to the lectin. Soaking for 15 min in 100 mM carbohydrate typically resulted in complete replacement of Man(alpha1-3)ManMe by the desired carbohydrate despite the involvement of lattice contacts at the binding site. Transferring the crystals for two weeks in carbohydrate-free artificial mother liquor resulted in the complete removal of the sugar from one of the two monomers in the asymmetric unit. Additional treatment of these crystals with 100 mM EDTA for two weeks resulted in removal of the structural calcium and manganese ions, which is accompanied by significant structural rearrangements of the loops that constitute the carbohydrate-binding site.

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

    Directory of Open Access Journals (Sweden)

    Sofie Van Holle

    2017-05-01

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

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

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Arab

    2010-07-01

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

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

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Arab

    2010-08-01

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

  11. A novel L-fucose-binding lectin from Fenneropenaeus indicus induced cytotoxicity in breast cancer cells.

    Science.gov (United States)

    Chatterjee, Biji; Ghosh, Krishna; Yadav, Nitin; Kanade, Santosh R

    2017-01-01

    Lectins are omnipresent in almost all life forms, being the proteins which specifically bind to carbohydrate moieties on the cell surface; they have been explored for their anti-tumour activities. In this study, we purified a fucose specific-lectin (IFL) from Fenneropenaeus indicus haemolymph using fucose-affinity column and characterized for its haemagglutination activity, carbohydrate specificity, dependency on cations and cytotoxicity against cancer cells. The lectin showed non-specificity against human erythrocytes. It was a Ca(2+)-dependent lectin which remained stable over wide pH and temperature ranges. The lectin showed effective dose dependent cytotoxicity against different human cancer cell lines and induced apoptosis in MCF-7 cells as evidenced by DNA ladder assay and PARP cleavage in a dose dependent manner. Moreover, an increased p21 level corresponding to cyclin D downregulation in response to IFL treatment was observed which might work as probable factors to inhibit cell growth and induce apoptosis of MCF-7 cells. Therefore, we report a novel lectin from the prawn haemolymph with high specificity for L-fucose and antiproliferative towards human cancer cells. However, further establishment of the modus operandi of this lectin is required to enable its biotechnological applications.

  12. Synthesis of a selective inhibitor of a fucose binding bacterial lectin from Burkholderia ambifaria.

    Science.gov (United States)

    Richichi, Barbara; Imberty, Anne; Gillon, Emilie; Bosco, Rosa; Sutkeviciute, Ieva; Fieschi, Franck; Nativi, Cristina

    2013-06-28

    Burkholderia ambifaria is a bacterium member of the Burkholderia cepacia complex (BCC), a closely related group of Gram-negative bacteria responsible for "cepacia syndrome" in immunocompromised patients. B. ambifaria produces BambL, a fucose-binding lectin that displays fine specificity to human fucosylated epitopes. Here, we report the first example of a synthetic ligand able to selectively bind, in the micromolar range, the pathogen-lectin BambL. The synthetic routes for the preparation of the α conformationally constrained fucoside are described, focusing on a totally diastereoselective inverse electron demand [4 + 2] Diels-Alder reaction. Isothermal titration calorimetry (ITC) demonstrated that this compound binds to the pathogen-associated lectin BambL with an affinity comparable to that of natural fucose-containing oligosaccharides. No binding was observed by LecB, a fucose-binding lectin from Pseudomonas aeruginosa, and the differences in affinity between the two lectins could be rationalized by modeling. Furthermore, SPR analyses showed that this fucomimetic does not bind to the human fucose-binding lectin DC-SIGN, thus supporting the selective binding profile towards B. ambifaria lectin.

  13. Lectin typing of Campylobacter jejuni using a novel quartz crystal microbalance technique

    Energy Technology Data Exchange (ETDEWEB)

    Yakovleva, Maria E., E-mail: maria.yakovleva@gmail.com [Department of Infectious Diseases and Medical Microbiology, Lund University, 223 62 Lund (Sweden); Moran, Anthony P. [Department of Microbiology, School of Natural Sciences, National University of Ireland, Galway (Ireland); Safina, Gulnara R. [Department of Analytical and Marine Chemistry, University of Gothenburg, 412 96 Gothenburg (Sweden); Wadstroem, Torkel [Department of Infectious Diseases and Medical Microbiology, Lund University, 223 62 Lund (Sweden); Danielsson, Bengt [Acromed Invest AB, Magistratsvaegen 10, 226 43 Lund (Sweden)

    2011-05-23

    Seven Campylobacter jejuni strains were characterised by a lectin typing assay. The typing system was based on a quartz crystal microbalance technique (QCM) with four commercially available lectins (wheat germ agglutinin, Maackia amurensis lectin, Lens culinaris agglutinin, and Concanavalin A), which were chosen for their differing carbohydrate specificities. Initially, the gold surfaces of the quartz crystals were modified with 11-mercaptoundecanoic acid followed by lectin immobilisation using a conventional amine-coupling technique. Bacterial cells were applied for lectin typing without preliminary treatment, and resonant frequency and dissipation responses were recorded. The adhesion of microorganisms on lectin surfaces was confirmed by atomic force microscopy. Scanning was performed in the tapping mode and the presence of bacteria on lectin-coated surfaces was successfully demonstrated. A significant difference in the dissipation response was observed for different C. jejuni strains which made it possible to use this parameter for discriminating between bacterial strains. In summary, the QCM technique proved a powerful tool for the recognition and discrimination of C. jejuni strains. The approach may also prove applicable to strain discrimination of other bacterial species, particularly pathogens.

  14. Effective inhibition of melanosome transfer to keratinocytes by lectins and niacinamide is reversible.

    Science.gov (United States)

    Greatens, Amanda; Hakozaki, Tomohiro; Koshoffer, Amy; Epstein, Howard; Schwemberger, Sandy; Babcock, George; Bissett, Donald; Takiwaki, Hirotsugu; Arase, Seiji; Wickett, R Randall; Boissy, Raymond E

    2005-07-01

    Skin pigmentation results in part from the transfer of melanized melanosomes synthesized by melanocytes to neighboring keratinocytes. Plasma membrane lectins and their glycoconjugates expressed by these epidermal cells are critical molecules involved in this transfer process. In addition, the derivative of vitamin B(3), niacinamide, can inhibit melanosome transfer and induce skin lightening. We investigated the effects of these molecules on the viability of melanocytes and keratinocytes and on the reversibility of melanosome-transfer inhibition induced by these agents using an in vitro melanocyte-keratinocyte coculture model system. While lectins and neoglycoproteins could induce apoptosis in a dose-dependent manner to melanocytes or keratinocytes in monoculture, similar dosages of the lectins, as opposed to neoglycoproteins, did not induce apoptosis to either cell type when treated in coculture. The dosages of lectins and niacinamide not affecting cell viability produced an inhibitory effect on melanosome transfer, when used either alone or together in cocultures of melanocytes-keratinocytes. Cocultures treated with lectins or niacinamide resumed normal melanosome transfer in 3 days after removal of the inhibitor, while cocultures treated with a combination of lectins and niacinamide demonstrated a lag in this recovery. Subsequently, we assessed the effect of niacinamide on facial hyperpigmented spots using a vehicle-controlled, split-faced design human clinical trial. Topical application of niacinamide resulted in a dose-dependent and reversible reduction in hyperpigmented lesions. These results suggest that lectins and niacinamide at concentrations that do not affect cell viability are reversible inhibitors of melanosome transfer.

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

    Science.gov (United States)

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

    2016-01-01

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

  16. Purification and partial characterization of a fructose-binding lectin from the leaves of Euphorbia helioscopia.

    Science.gov (United States)

    Rafiq, Shaista; Qadir, Sakeena; Wani, Ishfak Hussain; Ganie, Showkat Ahmad; Masood, Akbar; Hamid, Rabia

    2014-11-01

    A lectin was purified from leaves of Euphorbia helioscopia, by a combination of ion-exchange and gel filtration chromatography. On ion exchange using a DEAE- cellulose column in 0.2 M phosphate buffer, pH 7.2, the bound protein was eluted with a linear sodium chloride gradient of 0.1 M to 0.5 M. Further purification of the lectin was achieved by gel filtration on Sephadex G-100. Euphorbia helioscopia lectin (EHL) agglutinates only chick erythrocytes, showing no agglutination of all human blood group erythrocytes. The EHL induced hemagglutination is inhibited by fructose. The purified protein showed one band, both in non-denaturing PAGE and SDS-PAGE establishing the charge and size homogeneities of the lectin preparation. The molecular mass of the lectin as indicated by SDS-PAGE was approximately 31 kDa and that estimated from G-100 gel filtration chromatography was about 65 kDa establishing that the lectin is a homodimer. The lectin was stable within a temperature range of 0°C-40°C and exhibited a narrow range of pH stability, being optimally active at around pH 7. EHL also possesses antimicrobial activity and is an inhibitor of bacterial growth particularly Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli.

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

    Science.gov (United States)

    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.

  18. The Lectin Frontier Database (LfDB, and Data Generation Based on Frontal Affinity Chromatography

    Directory of Open Access Journals (Sweden)

    Jun Hirabayashi

    2015-01-01

    Full Text Available Lectins are a large group of carbohydrate-binding proteins, having been shown to comprise at least 48 protein scaffolds or protein family entries. They occur ubiquitously in living organisms—from humans to microorganisms, including viruses—and while their functions are yet to be fully elucidated, their main underlying actions are thought to mediate cell-cell and cell-glycoconjugate interactions, which play important roles in an extensive range of biological processes. The basic feature of each lectin’s function resides in its specific sugar-binding properties. In this regard, it is beneficial for researchers to have access to fundamental information about the detailed oligosaccharide specificities of diverse lectins. In this review, the authors describe a publicly available lectin database named “Lectin frontier DataBase (LfDB”, which undertakes the continuous publication and updating of comprehensive data for lectin-standard oligosaccharide interactions in terms of dissociation constants (Kd’s. For Kd determination, an advanced system of frontal affinity chromatography (FAC is used, with which quantitative datasets of interactions between immobilized lectins and >100 fluorescently labeled standard glycans have been generated. The FAC system is unique in its clear principle, simple procedure and high sensitivity, with an increasing number (>67 of associated publications that attest to its reliability. Thus, LfDB, is expected to play an essential role in lectin research, not only in basic but also in applied fields of glycoscience.

  19. Studies of hemolytical and antimicrobical action of Amanita virosa Secr. and Mycena pura /Fr./ Kumm. poisonous mushrooms lectins

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    Danileuchenko V. V.

    2010-02-01

    Full Text Available Aim. To study hemolytical and antimicrobical action of two new lectins, obtained from fruit bodies of poisonous basidial mushrooms of A. virosa Secr. and M. pura /Fr./ Kumm. Methods. Research on hemolytical action of lectins was conducted on the erythrocytes of human and animals. The experiments on osmotic protection of erythrocytes were performed in the presence of polyethylenglycols of different molecular mass (in a range from 400 to 4000 Da. Antimicrobical activity of lectins was studied by determination of area delay of growth of culture of different types of microorganisms on the Petri dish in an agaric media. Results. Both lectins hemolyse the erythrocytes of rabbit, human, rat and dog and do not hemolyse the erythrocytes of cow and ship in concentration of 1 mg/ml. The rabbit erythrocytes are most sensitive to hemolytical action of lectins, while hemolytic ability of A. virosa lectin is higher. Hemolysis was not observed in the presence of PEG of molecular mass over 1,350 Da. Action of lectins on 10 types of microorganisms was investigated. Lectins inhibited mainly growth of grammpositive microorganisms and protey. For most tested microorganisms antimicrobial action of Mycena lectin is stronger comparing with A. virosa lectin. Conclusions. Two new hemolytical lectins are found in the fruit bodies of mushrooms-basidiomycetes. The lectin formed ion-permeable pores in membrane of erythrocytes with the hydrodynamic diameter smaller than 2.3 nm and larger than 1.6 nm. These lectins displays also antimicrobial activity and by the sum of these features are similar to the cytolytic lectins of lower invertebrates.

  20. Animal lectins as self/non-self recognition molecules. Biochemical and genetic approaches to understanding their biological roles and evolution.

    Science.gov (United States)

    Vasta, G R; Ahmed, H; Fink, N E; Elola, M T; Marsh, A G; Snowden, A; Odom, E W

    1994-04-15

    In recent years, the significant contributions from molecular research studies on animal lectins have elucidated structural aspects and provided clues not only to their evolution but also to their multiple biological functions. The experimental evidence has suggested that distinct, and probably unrelated, groups of molecules are included under the term "lectin." Within the invertebrate taxa, major groups of lectins can be identified: One group would include lectins that show significant homology to membrane-integrated or soluble vertebrate C-type lectins. The second would include those beta-galactosyl-specific lectins homologous to the S-type vertebrate lectins. The third group would be constituted by lectins that show homology to vertebrate pentraxins that exhibit lectin-like properties, such as C-reactive protein and serum amyloid P. Finally, there are examples that do not exhibit similarities to any of the aforementioned categories. Moreover, the vast majority of invertebrate lectins described so far cannot yet be placed in one or another group because of the lack of information regarding their primary structure. (See Table 1.) Animal lectins do not express a recombinatorial diversity like that of antibodies, but a limited diversity in recognition capabilities would be accomplished by the occurrence of multiple lectins with distinct specificities, the presence of more than one binding site, specific for different carbohydrates in a single molecule, and by certain "flexibility" of the binding sites that would allow the recognition of a range of structurally related carbohydrates. In order to identify the lectins' "natural" ligands, we have investigated the interactions between those proteins and the putative endogenous or exogenous glycosylated substances or cells that may be relevant to their biological function. Results from these studies, together with information on the biochemical properties of invertebrate and vertebrate lectins, including their structural

  1. Physicochemical properties and oxidative inactivation of soluble lectin from water buffalo (Bubalus bubalis) brain.

    Science.gov (United States)

    Rizvi, Sabika; Banu, Naheed

    2008-03-01

    Lectins are carbohydrate-binding proteins present in a wide variety of plants and animals, which serve various important physiological functions. A soluble beta-galactoside binding lectin has been isolated and purified to homogeneity from buffalo brain using ammonium sulphate precipitation (40-70%) and gel permeation chromatography on Sephadex G50-80 column. The molecular weight of buffalo brain lectin (BBL) as determined by SDS-PAGE under reducing and non-reducing conditions was 14.2 kDa, however, with gel filtration it was 28.5 kDa, revealing the dimeric form of protein. The neutral sugar content of the soluble lectin was estimated to be 3.3%. The BBL showed highest affinity for lactose and other sugar moieties in glycosidic form, suggesting it to be a beta-galactoside binding lectin. The association constant for lactose binding as evidenced by Scatchard analysis was 6.6 x 10(3) M(-1) showing two carbohydrate binding sites per lectin molecule. A total inhibition of lectin activity was observed by denaturants like guanidine HCl, thiourea and urea at 6 M concentration. The treatment of BBL with oxidizing agent destroyed its agglutination activity, abolished its fluorescence, and shifted its UV absorption maxima from 282 to 250 nm. The effect of H2O2 was greatly prevented by lactose indicating that BBL is more stable in the presence of its specific ligand. The purified lectin was investigated for its brain cell aggregation properties by testing its ability to agglutinate cells isolated from buffalo and goat brains. Rate of aggregation of buffalo brain cells by purified protein was more than the goat brain cells. The data from above study suggests that the isolated lectin may belong to the galectin-1 family but is glycosylated unlike those purified till date.

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

    Directory of Open Access Journals (Sweden)

    M.L. Holanda

    2005-12-01

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

  3. Application of lectin microarray to crude samples: differential glycan profiling of lec mutants.

    Science.gov (United States)

    Ebe, Youji; Kuno, Atsushi; Uchiyama, Noboru; Koseki-Kuno, Shiori; Yamada, Masao; Sato, Takashi; Narimatsu, Hisashi; Hirabayashi, Jun

    2006-03-01

    We recently developed a novel system for lectin microarray based on the evanescent-field fluorescence-detection principle, by which even weak lectin-oligosaccharide interactions are detectable without a washing procedure. For its practical application, cell glycan analysis was performed for Chinese hamster ovary (CHO) cells and their glycan profile was compared with those of their glycosylation-defective Lec mutants. Each of the cell surface extracts gave a significantly different profile from that of the parental CHO cells in a manner reflecting denoted biosynthetic features. Hence, the developed lectin microarray system is considered to be fully applicable for differential glycan profiling of crude samples.

  4. Purification of a N-acetyl-D-galactosamine specific lectin from the orchid Laelia autumnalis.

    Science.gov (United States)

    Zenteno, R; Chávez, R; Portugal, D; Páez, A; Lascurain, R; Zenteno, E

    1995-10-01

    From the pseudobulbs of the orchid L. autumnalis a lectin was purified on immobilized porcine mucin with A + H blood group substance. This lectin is a dimeric glycoprotein of M(r) 12,000 with an Sw,20 of 2.2, showing haemagglutinating activity directed mainly to human A1 desialylated erythrocytes. The lectin possesses sugar specificity for N-acetyl-D-galactosamine and also shows high specificity for glycoproteins containing the T (galactose beta 1,3GA1NAc alpha 1,0 Ser/Thr) or the Tn antigen (GalNAc alpha 1,0 Ser/Thr).

  5. Cloning of cDNAs encoding C-type lectins from Elapidae snakes Bungarus fasciatus and Bungarus multicinctus.

    Science.gov (United States)

    Zha, H G; Lee, W H; Zhang, Y

    2001-12-01

    A number of C-type lectins with various biological activities have been purified and characterized from Viperidae snake venoms. In contrast, only a few reports could be found in literature concerning the C-type lectins in Elapidae snake venoms. Based on the published cDNA sequences of C-type lectins from Viperidae snake venoms, oligonucleotide primers were designed and used to screen the cDNA libraries made from the venom glands of Bungarus fasciatus and Bungarus multicinctus. This allowed the cloning of three full length cDNAs encoding C-type lectins. The encoded proteins, named BFL-1, BFL-2 and BML, exhibit high degrees of sequence identities with Viperidae snake venom saccharide-binding lectins (around 60% with Trimeresurus stejnegeri venom lectin, Crotalus atrox venom lectin and Agkistrodon piscivorus venom lectin). They show much less identities with other venom C-type lectin-like proteins (around 30% with the platelet glycoprotein Ib-binding protein from Agkistrodon blomhoffi venom and the factor IX/X-binding protein from Trimeresurus flavoviridis venom). The cDNAs revealed that the precursors contain potential signal peptides characterized by a hydrophobic core. To our knowledge, these are the first cDNA cloning of group VII C-type lectins (Drickamer K. 1993. Prog. Nucleic Acid Res. Mol. Biol. 45, 207-232) from Elapidae snake venom glands.

  6. Detection of Sugar-Lectin Interactions by Multivalent Dendritic Sugar Functionalized Single-Walled Carbon Nanotubes

    CERN Document Server

    Vasu, K S; Bagul, R S; Jayaraman, N; Sood, A K; 10.1063/1.4739793

    2012-01-01

    We show that single walled carbon nanotubes (SWNT) decorated with sugar functionalized poly (propyl ether imine) (PETIM) dendrimer is a very sensitive platform to quantitatively detect carbohydrate recognizing proteins, namely, lectins. The changes in electrical conductivity of SWNT in field effect transistor device due to carbohydrate - protein interactions form the basis of present study. The mannose sugar attached PETIM dendrimers undergo charge - transfer interactions with the SWNT. The changes in the conductance of the dendritic sugar functionalized SWNT after addition of lectins in varying concentrations were found to follow the Langmuir type isotherm, giving the concanavalin A (Con A) - mannose affinity constant to be 8.5 x 106 M-1. The increase in the device conductance observed after adding 10 nM of Con A is same as after adding 20 \\muM of a non - specific lectin peanut agglutinin, showing the high specificity of the Con A - mannose interactions. The specificity of sugar-lectin interactions was chara...

  7. Lectin Domains of Polypeptide GalNAc Transferases Exhibit Glycopeptide Binding Specificity

    DEFF Research Database (Denmark)

    Pedersen, Johannes W; Bennett, Eric P; Schjoldager, Katrine T-B G;

    2011-01-01

    UDP-GalNAc:polypeptide a-N-acetylgalactosaminyltransferases (GalNAc-Ts) constitute a family of up to 20 transferases that initiate mucin-type O-glycosylation. The transferases are structurally composed of catalytic and lectin domains. Two modes have been identified for the selection...... of glycosylation sites by GalNAc-Ts: confined sequence recognition by the catalytic domain alone, and concerted recognition of acceptor sites and adjacent GalNAc-glycosylated sites by the catalytic and lectin domains, respectively. Thus far, only the catalytic domain has been shown to have peptide sequence...... on sequences of mucins MUC1, MUC2, MUC4, MUC5AC, MUC6, and MUC7 as well as a random glycopeptide bead library, we examined the binding properties of four different lectin domains. The lectin domains of GalNAc-T1, -T2, -T3, and -T4 bound different subsets of small glycopeptides. These results indicate...

  8. Single step synthesis of carbohydrate monolithic capillary columns for affinity chromatography of lectins

    NARCIS (Netherlands)

    Tetala, K.K.R.; Chen, B.; Visser, G.M.; Beek, van T.A.

    2007-01-01

    Carbohydrate monolithic beds were synthesized in a single step in capillary columns to study affinity chromatography of lectins. In this method, carbohydrates (-galactose, -glucose, and -mannose) with an easy to synthesize alkene terminated tetraethylene glycol spacer were used as functional

  9. The pattern-recognition molecule mannan-binding lectin (MBL) in the pathophysiology of diabetic nephropathy

    DEFF Research Database (Denmark)

    Axelgaard, Esben; Thiel, Steffen; Hansen, Troels Krarup

    The pattern-recognition molecule mannan-binding lectin (MBL) in the pathophysiology of diabetic nephropathy Esben Axelgaard*; Steffen Thiel*; Jakob Appel Østergaard† and Troels Krarup Hansen† *Department of Biomedicine, Aarhus University, Wilhelm Meyer´s Allé 4, 8000 Aarhus C, Denmark. †Department...... of Clinical Medicine, Aarhus University and The Danish Diabetes Academy, Nørrebrogade 44, build. 3, 8000 Aarhus C, Denmark The complement system is part of the innate immune system and is an important part of the first line of defence against pathogens. Mannan-binding lectin (MBL) is one of the pattern-recognition...... mechanisms are proposed, 1) the formation of neoepitopes for MBL pattern recognition on host cells would enable lectin pathway activation and 2) inactivation of complement regulatory proteins by glycation that may exaggerate complement attack on host cells. MBL initiates the lectin pathway through binding...

  10. Novel hemagglutinating, hemolytic and cytotoxic activities of the intermediate subunit of Entamoeba histolytica lectin

    Science.gov (United States)

    Kato, Kentaro; Yahata, Kazuhide; Gopal Dhoubhadel, Bhim; Fujii, Yoshito; Tachibana, Hiroshi

    2015-01-01

    Galactose and N-acetyl-D-galactosamine (Gal/GalNAc) inhibitable lectin of Entamoeba histolytica, a common protozoan parasite, has roles in pathogenicity and induction of protective immunity in mouse models of amoebiasis. The lectin consists of heavy (Hgl), light (Lgl), and intermediate (Igl) subunits. Hgl has lectin activity and Lgl does not, but little is known about the activity of Igl. In this study, we assessed various regions of Igl for hemagglutinating activity using recombinant proteins expressed in Escherichia coli. We identified a weak hemagglutinating activity of the protein. Furthermore, we found novel hemolytic and cytotoxic activities of the lectin, which resided in the carboxy-terminal region of the protein. Antibodies against Igl inhibited the hemolytic activity of Entamoeba histolytica trophozoites. This is the first report showing hemagglutinating, hemolytic and cytotoxic activities of an amoebic molecule, Igl. PMID:26354528

  11. Construction and immunogenicity of a codon-optimized Entamoeba histolytica Gal-lectin-based DNA vaccine.

    Science.gov (United States)

    Gaucher, Denis; Chadee, Kris

    2002-09-10

    Invasive amebiasis caused by Entamoeba histolytica is the third leading parasitic cause of mortality, and there are no vaccines available to help control the disease. The galactose-adherence lectin (Gal-lectin) is the parasite's major molecule allowing it to adhere to colonic mucin for colonization and to target cells for tissue destruction. It is immunodominant and is regarded as the most promising candidate molecule to be included in a subunit vaccine against amebiasis. In this study, we are reporting the construction of a codon-optimized DNA vaccine encoding a portion of the Gal-lectin heavy subunit that includes the carbohydrate recognition domain (CRD), and its in vivo testing in mice. The vaccine stimulated a Th1-type Gal-lectin-specific cellular immune response as well as the development of serum antibodies that recognized a recombinant portion of the heavy subunit, and that inhibited the adherence of trophozoites to target cells in vitro.

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

    Directory of Open Access Journals (Sweden)

    Alen’kina S.A.

    2009-12-01

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

  13. Reactivities of N-acetylgalactosamine-specific lectins with human IgA1 proteins

    DEFF Research Database (Denmark)

    Moore, J.S.; Kulhavy, R.; Tomana, M.

    2007-01-01

    Lectins are proteins with specificity of binding to certain monosaccharides or oligosaccharides. They can detect abnormal glycosylation patterns on immunoglobulins in patients with various chronic inflammatory diseases, including rheumatoid arthritis and IgA nephropathy (IgAN). However, lectins...... exhibit binding heterogeneity, depending on their source and methods of isolation. To characterize potential differences in recognition of terminal N-acetylgalactosamine (GalNAc) on IgA1, we evaluated the binding characteristics of several commercial preparations of GalNAc-specific lectins using a panel...... of IgA1 and, as controls, IgA2 and IgG myeloma proteins. These lectins originated from snails Helix aspersa (HAA) and Helix pomatia (HPA), and the plant Vicia villosa (VV). Only HAA and HPA bound exclusively to IgA1, with its O-linked glycans composed of GalNAc, galactose, and sialic acid. In contrast...

  14. Lectin Histochemical Study of Vasculogenesis During Rat Pituitary Morphogenesis

    Directory of Open Access Journals (Sweden)

    Ali Reza Ebrahimzadeh Bideskan

    2011-01-01

    Full Text Available Objective(s The aim of this study was to investigate glycoconjugates distribution patterns as well as their changes during the course of pituitary portal vasculogenesis and angiogenesis.Materials and MethodsFormalin fixed paraffin sections of 10 to 20 days of Sprague Dawly rat fetuses were processed for histochemical studies using four different horseradish peroxidase (HRP conjugated lectins. Orange peel fungus (OFA, Vicica villosa (VVA, Glycine max (SBA and Wistaria floribunda (WFA specific for α-L-Fucose, D-Gal, α, ß-D-GalNAc and D- GalNAc terminal sugars of glycoconjugates respectively.ResultsOur finding indicated that adenohypophysal cells reacted with OFA on gestational day 10 (E10 and increased progressively to E14. Staining intensity did not change from days 14 to17, then after increased following days to E20 significantly (P< 0.05. A few cells around Rathke’s pouch reacted with VVA on E13, increased to E14 and decreased significantly afterward (P< 0.05. Reaction of some cells around Rathke’s pouch reacted with SBA on E14. This visible reaction was the same as E18 and decreased later (P< 0.05. Many cells around Rathke’s pouch reacted with WFA on E13 and increased on E 14 and E15 and decreased thereafter (P< 0.05.ConclusionReactions of OFA and other tested lectins with endothelial cells around Rathke’s pouch and developing pars distalis were different. These results suggest that embryonic origin of hypophiseal pituitary portal (HPP system endothelial cells are not the same and our finding also indicated that glycoconjugates with terminal sugars α-L-Fucose, D-Gal, α, ß-D-GalNAc may play critical role(s in cell interactions and tissue differentiations such as vasculogensis and angiogenesis as well as other developmental precursors in formation of the pituitary gland.

  15. Interaction indole-3-acetic acid IAA with lectin Canavalia maritima seeds reveal new function of lectins in plant physiology

    Energy Technology Data Exchange (ETDEWEB)

    Silva Filho, J.C.; Santi-Gadelha, T.; Gadelha, C.A.A.; Delatorre, P. [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil); Teixeira, C.S.; Rocha, B.A.M.; Nobrega, R.B.; Alencar, K.L.L.; Cavada, B.S. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil)

    2012-07-01

    Full text: Lectins are a class of proteins of non-immune origin characterized by its capability in interacts specifically and reversibly to mono and oligosaccharides. In plant several possible roles have been suggested including their function in seed maturation, cell wall assembly, defense mechanisms, or rhizobial nodulation of legume roots. Nearly all application and proposed of the plant lectins are based on their specific carbohydrate binding. However, it has been reported that lectins from legumes, might interact with other molecules, such as non proteic amino acids and hydrophobic compounds. This study show the first the crystal structure based on molecular replacement of the Canavalia maritima (CML) complexed with IAA correlated with possible role in plant development. Purified CML was dissolved in 20 mMTrisHCl pH 7.6 containing 5 mM IAA, the suitable co-crystals from CML-IAA complex grew in condition 4 of screen I (0.1 M TrisHCl pH 8.5 and 2.0 M ammonium sulfate). This crystal belong to the orthorhombic space group I222 with unit-cell parameters a = 67.1 ; b = 70.7 , c = 97.7 , The structure was refined at 2.1 of resolution to a final R factor of 20.63 % and an R free of 22.54 %. To check the relative position of the IAA molecule in relation to the biological assemble of the CML, the tetrameric structure was generate by crystallographic symmetry. IAA molecules are positioned in the central cavity. The IAA is stabilized by interacting through hydrogen bounds and Van der Waals forces with the amino acids residues Ser 108 and Asn131, and two water molecules. The hydrophilic interactions occur between IAA and side chains of Ser 108, Asn131 and water molecules 26 and 31 by H-bonds. The OG oxygen from Ser108 display H-bonds with O2 and O3 oxygen atoms from IAA, 3.1 and 2.8 respectively. The tetrameric structure of CML complexed with IAA revels which this protein can act during the seedling in plant development. (author)

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

    Directory of Open Access Journals (Sweden)

    F.C. Lopes

    2005-06-01

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

  17. Molecular cloning and characterization of multiple isoforms of the snowdrop (Galanthus nivalis L.) lectin.

    Science.gov (United States)

    Van Damme, E J; De Clercq, N; Claessens, F; Hemschoote, K; Peeters, B; Peumans, W J

    1991-12-01

    Screening of a copy-DNA (cDNA) library constructed from RNA isolated from young developing ovaries of snowdrop (Galanthus nivalis) resulted in the isolation of five lectin clones which clearly differed from each other with regard to their nucleotide sequence and deduced amino-acid sequence. Sequence comparison between the coding regions of different lectin cDNAs revealed the highest homology between lectin clones LECGNA 3 and LECGNA 5, showing 96.4% and 93.6% similarity at the nucleotide level and at the deduced amino-acid level, respectively, whereas lectin clones LECGNA 1 and LECGNA 3 showed the lowest homology of 81.6% and 68.6% for the nucleotide sequence and the amino-acid sequence, respectively. Only very few lectin cDNA clones containing a polyadenylated tail could be isolated. Moreover all these cDNA clones were derived from isolectin 3 and showed some variability within the length of the 3' untranslated region. The major transcription initiation site was located 30 bases upstream from the AUG codon as could be deduced from primer-extension analysis. Taking into account the small 5' untranslated region of the lectin clones, the size of the lectin mRNA, which is approx. 780 nucleotides as determined by Northern blot analysis, is in good agreement with the length of the cDNA clones isolated. Besides the ovary tissue, both the leaf and the flower tissue were also shown to express the lectin mRNA in a flowering snowdrop plant.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

  19. Isolation and antiproliferative activity of Lotus corniculatus lectin towards human tumour cell lines.

    Science.gov (United States)

    Rafiq, Shaista; Majeed, Rabiya; Qazi, Asif Khurshid; Ganai, Bashir Ahmad; Wani, Ishfak; Rakhshanda, Syed; Qurishi, Yasrib; Sharma, P R; Hamid, Abid; Masood, Akbar; Hamid, Rabia

    2013-12-15

    The objective of the study was to investigate the anti cancer activity of a lectin isolated from Lotus corniculatus seeds. A tetrameric 70kDa galactose specific lectin was purified using two step simple purification protocol which involved affinity chromatography on AF-BlueHC650M and gel filtration on Sephadex G-100. The lectin was adsorbed on AF-BlueHC650M and desorbed using 1M NaCl in the starting buffer. Gel filtration on Sephadex G-100 yielded a major peak absorbance that gave two bands of 15kDa and 20kDa in SDS PAGE. Hemagglutination activity was completely preserved, when the temperature was in the range of 20-60°C. However, drastic reduction in activity occurred at temperatures above 60°C. Full hemagglutination activity was retained at ambient pH 4-12. Thereafter no activity was observed above pH 13. Hemaglutination of the lectin was inhibited by d-galactose. The lectin showed a strong antiproliferative activity towards human leukemic (THP-1) cancer cells followed by lung cancer (HOP62) cells and HCT116 with an IC50 of 39μg/ml and 50μg/ml and 60μg/ml respectively. Flow cytometry analysis showed an increase in the percentage of cells in sub G0G1 phase confirming that Lotus corniculatus lectin induced apoptosis. Morphological observations showed that Lotus corniculatus lectin (LCL) treated THP-1 cells displayed apparent apoptosis characteristics such as nuclear fragmentation, appearance of membrane enclosed apoptotic bodies and DNA fragmentation. Lotus corniculatus lectin (LCL) effectively inhibits the cell migration in a dose dependent manner as indicated by the wound healing assay.

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

    Science.gov (United States)

    Biswas, Himadri; Chattopadhyaya, Rajagopal

    2016-04-01

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

  1. Isolation and comparative analysis of the wheat TaPT2 promoter: identification in silico of new putative regulatory motifs conserved between monocots and dicots.

    Science.gov (United States)

    Tittarelli, A; Milla, L; Vargas, F; Morales, A; Neupert, C; Meisel, L A; Salvo-G, H; Peñaloza, E; Muñoz, G; Corcuera, L J; Silva, H

    2007-01-01

    Phosphorus deficiency is one of the major nutrient stresses affecting plant growth. Plants respond to phosphate (Pi) deficiency through multiple strategies, including the synthesis of high-affinity Pi transporters. In this study, the expression pattern of one putative wheat high-affinity phosphate transporter, TaPT2, was examined in roots and leaves under Pi-deficient conditions. TaPT2 transcript levels increased in roots of Pi-starved plants. A 579 bp fragment of the TaPT2 promoter is sufficient to drive the expression of the GUS reporter gene specifically in roots of Pi-deprived wheat. This TaPT2 promoter fragment was also able to drive expression of the GUS reporter gene in transgenic Arabidopsis thaliana, under similar growth conditions. Conserved regions and candidate regulatory motifs were detected by comparing this promoter with Pi transporter promoters from barley, rice, and Arabidopsis. Altogether, these results indicate that there are conserved cis-acting elements and trans-acting factors that enable the TaPT2 promoter to be regulated in a tissue-specific and Pi-dependent fashion in both monocots and dicots.

  2. Characterization of tobacco expressing functional oat phytochrome. Domains responsible for the rapid degradation of Pfr are conserved between monocots and dicots

    Energy Technology Data Exchange (ETDEWEB)

    Cherry, J.R.; Vierstra, R.D. (Univ. of Wisconsin, Madison (United States)); Hershey, H.P. (E.I.du Pont de Nemours and Co., Wilmington, DE (United States))

    1991-07-01

    Constitutive expression of a chimeric oat phytochrome gene in tobacco (Nicotiana tabacum) results in the accumulation of a functional 124-kilodalton photoreceptor that markedly alters the phenotype of light-grown tobacco. Here, we provide a detailed phenotypic and biochemical characterization of homozygous tobacco expressing high levels of oat phytochrome. Phenotypic changes include a substantial inhibition of stem elongation, decreased apical dominance, increased leaf chlorophyll content, and delayed leaf senescence. Oat phytochrome synthesized in tobacco is indistinguishable from that present in etiolated oats, having photoreversible difference spectrum maxima at 665 and 730 nanometers, exhibiting negligible dark reversion of phytochrome - far red-absorbing from (Pfr) to phytochrome - red-absorbing form (Pr), and existing as a dimer with an apparent size of approximately 300 kilodaltons. Heterodimers between the oat and tobacco chromoproteins were detected. Endogenous tobacco phytochrome and transgenically expressed oat phytochrome are rapidly degraded in vivo upon photoconversion of Pr to Pfr. Breakdown of both oat and tobacco Pfr is associated with the accumulation of ubiquitin-phytochrome conjugates, suggesting that degradation occurs via the ubiquitin-dependent proteolytic pathway. This result indicates that the factors responsible for selective recognition of Pfr by the ubiquitin pathway are conserved between monocot and dicot phytochromes. More broadly, it demonstrates that the domains(s) within a plant protein responsible for its selective breakdown can be recognized by the degradation machinery of heterologous species.

  3. Characterization of storage material in cultured fibroblasts by specific lectin binding in lysosomal storage diseases.

    Science.gov (United States)

    Virtanen, I; Ekblom, P; Laurila, P; Nordling, S; Raivio, K O; Aula, P

    1980-11-01

    The lysosomal storage material in cultured fibroblasts from patients with various lysosomal storage diseases was characterized by fluorescence microscopy using lectins specific for different saccharide moieties. In normal fibroblasts and cultured amniotic fluid cells lectins specific for mannosyl and glucosyl moieties, Con A and LcA gave a bright perinuclear cytoplasmic staining corresponding to the localization of endoplasmic reticulum in the cells. All other lectins stained the Golgi apparatus as a juxtanuclear reticular structure. In fucosidosis fibroblasts, only lectins specific for fucosyl groups LTA and UEA, distinctly stained the lysosomal inclusions. The lysosomes in mannosidosis fibroblasts did not react with Con A and LcA, both specific for mannosyl moieties of glycoconjugates, but were brightly labeled with WGA, a lectin specific for N-acetyl glucosaminyl moieties. In I-cell fibroblasts, the numerous perinuclear phase-dense granules, representing abnormal lysosomes, were labeled with every lectin used. In fibroblasts from patients with Salla disease, a newly discovered lysosomal storage disorder, the lysosomes were brightly stained only with LPA, indicating the presence of increased amounts of sialic acid residues in the lysosomal inclusions.

  4. Lectin domains of polypeptide GalNAc transferases exhibit glycopeptide binding specificity.

    Science.gov (United States)

    Pedersen, Johannes W; Bennett, Eric P; Schjoldager, Katrine T-B G; Meldal, Morten; Holmér, Andreas P; Blixt, Ola; Cló, Emiliano; Levery, Steven B; Clausen, Henrik; Wandall, Hans H

    2011-09-16

    UDP-GalNAc:polypeptide α-N-acetylgalactosaminyltransferases (GalNAc-Ts) constitute a family of up to 20 transferases that initiate mucin-type O-glycosylation. The transferases are structurally composed of catalytic and lectin domains. Two modes have been identified for the selection of glycosylation sites by GalNAc-Ts: confined sequence recognition by the catalytic domain alone, and concerted recognition of acceptor sites and adjacent GalNAc-glycosylated sites by the catalytic and lectin domains, respectively. Thus far, only the catalytic domain has been shown to have peptide sequence specificity, whereas the primary function of the lectin domain is to increase affinity to previously glycosylated substrates. Whether the lectin domain also has peptide sequence selectivity has remained unclear. Using a glycopeptide array with a library of synthetic and recombinant glycopeptides based on sequences of mucins MUC1, MUC2, MUC4, MUC5AC, MUC6, and MUC7 as well as a random glycopeptide bead library, we examined the binding properties of four different lectin domains. The lectin domains of GalNAc-T1, -T2, -T3, and -T4 bound different subsets of small glycopeptides. These results indicate an additional level of complexity in the initiation step of O-glycosylation by GalNAc-Ts.

  5. Cytokine production induced by marine algae lectins in BALB/c mice splenocytes.

    Science.gov (United States)

    Monteiro Abreu, Ticiana; Castelo Melo Silva, Luana Maria; Vanderlei, Edfranck Sousa Oliveira; de Melo, Cristiane Moutinho Lagos; Pereira, Valeria Rego Alves; Barros Benevides, Norma Maria

    2012-09-01

    Marine algae can serve as sources of bioactive compounds and currently have been shown their potential biological and pharmaceutical applications. Marine algae lectins have been shown to be effective at controlling inflammatory processes. This work aimed to analyze the immunostimulatory properties of lectins from the marine algae Solieria filiformis (SfL), Pterocladiella capillacea (PcL) and Caulerpa cupressoides (CcL). This analysis was performed on BALB/c mouse splenocytes by measuring cytokine and nitric oxide production and cellular damage using tests of cytotoxicity and cell viability. These lectins were not cytotoxic (1-100 μg/mL), and were not able to induce IFN-γ and IL-2 production. IL- 10 production was induced at high levels by all lectins tested. Treatment with SfL induced IL-6 production at higher levels at all experimental times, whereas treatment with PcL and CcL induced higher levels only in 24 and 72 h. Treatment with SfL did not result in nitrite oxide production, whereas treatment with PcL or CcL was able to induce nitrite release at high levels (after 24, 48 and 72 h). Lesser cellular damage (5%) was observed in splenocytes treated with these lectins (10 μg/mL). Thus, the lectins from these algae were not cytotoxic, promoted increased in cell viability and induced Th2 immune responses in mouse splenocytes, indicating that they have anti-inflammatory effects.

  6. Interaction of a human blood group Sd(a-) Tamm-Horsfall glycoprotein with applied lectins.

    Science.gov (United States)

    Wu, J H; Watkins, W M; Chen, C P; Song, S C; Wu, A M

    1996-04-22

    Unlike the human blood group Sd(a+) Tamm-Horsfall glycoprotein (THGP), the Sd(a-) one lacks terminal GalNAcbeta1--> residues at the nonreducing ends. The binding properties of this glycoprotein and its asialo product with lectins were characterized by quantitative precipitin (QPA) and precipitin inhibition assays. Among 20 lectins tested by QPA, both native and asialo Sd(a-) THGP reacted best with Abrus precatorius and Ricinus communis and completely precipitated the lectin added. They also precipitated well Wistaria floribunda (WFA), Glycine max (SBA), Bauhinia purpurea alba, abrin-a and ricin, all of which recognize the Galbeta1--> 4GlcNAcbeta1--> sequence, although at different strength. The lectin-glycan interactions were inhibited by Galbeta1--> 4GlcNAc and Galbeta1--> 4Glc. When the precipitability of Sd(a-) THGP was compared with that of the Sd(a+) phenotype, the native Sd(a-) THGP exhibited a 40% lesser affinity for WFA, SBA, WGA and mistletoe lectin-I (ML-I). Mapping the precipitation and inhibition profiles of the present study and the results of THGP Sd(a+), it is concluded that Sd(a-) THGP showed a strongly diminished affinity for GalNAcbeta1--> active lectins (SBA and WFA) than the Sd(a+) phenotype.

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

    Science.gov (United States)

    Shang, Yuqin; Zeng, Yun; Zeng, Yong

    2016-02-02

    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.

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

    Directory of Open Access Journals (Sweden)

    Yoko Itakura

    2017-05-01

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

  9. Effect of leguminous lectins on the growth of Rhizobium tropici CIAT899.

    Science.gov (United States)

    de Vasconcelos, Mayron Alves; Cunha, Cláudio Oliveira; Arruda, Francisco Vassiliepe Sousa; Carneiro, Victor Alves; Bastos, Rafaela Mesquita; Mercante, Fábio Martins; do Nascimento, Kyria Santiago; Cavada, Benildo Sousa; dos Santos, Ricardo Pires; Teixeira, Edson Holanda

    2013-05-17

    Rhizobium tropici is a Gram-negative bacterium that induces nodules and fixed atmospheric nitrogen in symbiotic association with Phaseolus vulgaris (common bean) and some other leguminous species. Lectins are proteins that specifically bind to carbohydrates and, consequently, modulate different biological functions. In this study, the d-glucose/ d-mannose-binding lectins (from seeds of Dioclea megacarpa, D. rostrata and D. violacea) and D-galactose-binding lectins (from seeds of Bauhinia variegata, Erythina velutina and Vatairea macrocarpa) were purified using chromatographic techniques and evaluated for their effect on the growth of R. tropici CIAT899. All lectins were assayed with a satisfactory degree of purity according to SDS-PAGE analysis, and stimulated bacterial growth; in particular, the Dioclea rostrata lectin was the most active among all tested proteins. As confirmed in the present study, both d-galactose- and d-glucose/d-mannose-binding lectins purified from the seeds of leguminous plants may be powerful biotechnological tools to stimulate the growth of R. tropici CIAT99, thus improving symbiotic interaction between rhizobia and common bean and, hence, the production of this field crop.

  10. Effect of Leguminous Lectins on the Growth of Rhizobium tropici CIAT899

    Directory of Open Access Journals (Sweden)

    Mayron Alves de Vasconcelos

    2013-05-01

    Full Text Available Rhizobium tropici is a Gram-negative bacterium that induces nodules and fixed atmospheric nitrogen in symbiotic association with Phaseolus vulgaris (common bean and some other leguminous species. Lectins are proteins that specifically bind to carbohydrates and, consequently, modulate different biological functions. In this study, the d-glucose/ d-mannose-binding lectins (from seeds of Dioclea megacarpa, D. rostrata and D. violacea and D-galactose-binding lectins (from seeds of Bauhinia variegata, Erythina velutina and Vatairea macrocarpa were purified using chromatographic techniques and evaluated for their effect on the growth of R. tropici CIAT899. All lectins were assayed with a satisfactory degree of purity according to SDS-PAGE analysis, and stimulated bacterial growth; in particular, the Dioclea rostrata lectin was the most active among all tested proteins. As confirmed in the present study, both d-galactose- and d-glucose/d-mannose-binding lectins purified from the seeds of leguminous plants may be powerful biotechnological tools to stimulate the growth of R. tropici CIAT99, thus improving symbiotic interaction between rhizobia and common bean and, hence, the production of this field crop.

  11. A seedling specific vegetative lectin gene is related to development in Cicer arietinum.

    Science.gov (United States)

    Esteban, Rocío; Dopico, Berta; Muñoz, Francisco J; Romo, Silvia; Labrador, Emilia

    2002-04-01

    Plant lectins are a group of glycoproteins with the ability to recognize and bind carbohydrate ligands. Seed lectins function as storage and defense proteins, but the specific function of vegetative lectins is uncertain. In this paper we describe the characterization of a clone, CanVLEC, encoding a vegetative lectin from chickpea (Cicer arietinum L. cv. Castellana). The expression of the CanVLEC gene was specific in seedlings, mostly in hooks and elongating epicotyls, and no expression was detected in adult plants. The level of chickpea vegetative lectin transcripts in epicotyls decreased through the epicotyl growth suggesting a relationship to development. Treatment with indoleacetic acid (IAA) and brassinolides (BR), hormones that promoted elongation in chickpea epicotyl, increased the level of CanVLEC mRNA, supporting a relationship to growth. CanVLEC is drastically down regulated by water deficit ruling out its possible involvement in plant response to water stress, unlike other vegetative lectins. CanVLEC protein may be targeted to an extracellular location owing to the presence of a signal peptide.

  12. Isolation and Characterization of Midgut Lectin From Aedes aegypti (L. (Diptera: Culicidae

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    Tahany Hassan Ayaad

    2015-12-01

    Full Text Available ABSTRACT The present investigation deals with the isolation and characterization of a lectin from Aedes aegypti (Ae aegypti female mid gut extract that agglutinates various mammalian red blood cells (RBCs such as human three groups A, B, and O (RH+, mouse, rat, guinea-pig, sheep and goat erythrocytes. The highest activity of both crude and isolated mid gut lectins were detected against sheep RBCs. Using (NH42 SO4 fractionation, ion-exchange and mannose-CNBr-Sepharose 6B affinity chromatography techniques, Ae. aegypti midgut lectin (Aelec was purified to homogeneity.Isoelectric focusing (IEF and reducing SDS/PAGE revealed that the isolated mid gut lectin had isoelectric point (PI of 5.90, and subunits approximate molecular weights of 35.50 and 27.35 KDa. The hemagglutination (HA of lectins were Ca2+ - independent and heat-resistant. The sugar specificity of the purified Aelec was strongly inhibited by D (+-mannose and raffinose, followed by D (+ glucose. N-acetyl-D-manosamine and N-acetyl-D-glucosamine were moderate inhibitors. None of the lectins were inhibited by the disaccharides such as galactose, lactose, trehalose (IC50 up to 200 mM or fetuin up to 1% but the glycosubstances mucin and laminarin were strong inhibitors up to very low concentrations (0.030 - 0.003%.

  13. Molecular Characterization of a New Lectin from the Marine Alga Ulva pertusa

    Institute of Scientific and Technical Information of China (English)

    Sheng WANG; Fu-Di ZHONG; Yong-Jiang ZHANG; Zu-Jian WU; Qi-Ying LIN; Lian-Hui XIE

    2004-01-01

    A new lectin, named UPL1, was purified from a green alga Ulvapertusa by an affinitychromatography on the bovine-thyroglobulin-Sepharose 4B column. The molecular mass of the algal lectinwas about 23 kD by SDS-PAGE, and it specifically agglutinated rabbit erythrocytes. The hemagglutinatingactivity for rabbit erythrocytes could be inhibited by bovine thyroglobulin and N-acetyl-D-glucosamine. Thelectin UPL1 required divalent cations for maintenance of its biological activity, and was heat-stable, and hadhigher activity within pH 6-8. The N-terminal amino acid sequence of the purified lectin was determined(P83209) and a set of degenerate primers were designed. The full-length cDNA of the lectin was cloned byrapid amplification of cDNA ends (RACE) method (AY433960). Sequence analysis of upl1 indicated it was1084 bp long, and encoded a premature protein of 203 amino acids. The N-terminal sequence of the matureUPL1 polypeptide started at amino acid 54 of the deduced sequence from the cDNA, indicating 53 aminoacids lost due to posttranslational modification. The primary structure of the Ulvapertusa lectin did not showamino acid sequence similarity with known plant and animal lectins. Hence, this protein may be the paradigmof a novel lectin family.

  14. Interactions of Pseudomonas aeruginosa PA-IIL lectin with quail egg white glycoproteins.

    Science.gov (United States)

    Lerrer, B; Gilboa-Garber, N

    2001-12-01

    Pseudomonas aeruginosa produces several lectins, including the galactophilic PA-IL and the fucose- and mannose-binding PA-IIL. The great advantage of these two lectins is their stability in purified preparations. Following observations that pigeon egg white blocks Escherichia coli P-fimbriae and PA-IL, we examined the interactions of diverse avian egg white components with PA-IIL. This lectin may represent both mannose- and fucose-specific microbial adhesins. For comparison, Con A (which also binds mannose) and Ulex europaeus lectin (UEA-I, which binds fucose) were analyzed in parallel. The lectin interactions with chicken, quail, and pigeon egg whites and several purified chicken egg white glycoproteins were examined by a hemagglutination inhibition test and Western blotting. Both analyses showed that like Con A and unlike UEA-I, which was not sensitive to any of these three egg whites, PA-IIL most strongly reacted with the quail egg white. However, in contrast with Con A, its interactions with the chicken egg white components, excluding avidin, were very poor. The results of this study might indicate the possibility that some of the egg white components that interacted with the above two mannose-binding lectins (exhibiting individual heterogeneity) might be associated with the innate immunity against mannose-specific microbial or viral adhesion during the fowl embryonic period.

  15. Purification of melibiose-binding lectins from two cultivars of Chinese black soybeans

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A dimeric 50 kDa melibiose-binding leetin was isolated from the seeds of the cultivar of soybean (Glycine max), called the small glossy black soybean. The isolation procedure comprised ion exchange chromatography on Q Sepharose, SP Sepharose and Mono Q followed by gel filtration on Superdex 75. The lectin was adsorbed on all three ion exchangers, and it exhibited an N-terminal sequence identical to that of soybean iectin. Of all the sugars tested, melibiose most potently inhibited the hemagglutinating activity of the lectin, which was stable between pH 3-12 and 0-70℃. The lectin evoked maximal mitogenic response at about the same molar concentration as Con A. However, the response was much weaker. The soybean iectin inhibited the activity of HIV-1 reverse transcriptase as well as the proliferation of breast cancer MCF7 cells and hepatoma HepG2 cells with an IC of 2.82 μM, 2.6 μM and 4.1 μM, respectively. There was no antifungal activity. Another lectin was isolated from a different cnltivar of soybean called little black soybean. The lectin was essentially similar to small glossy black soy-bean iectin except for a larger subunit molecular mass (31 kDa), a more potent mitogenic activity and lower thermostability. The results indicate that different cultivars of soybean produce lectins that are not identical in every aspect.

  16. Selectivity among two lectins: probing the effect of topology, multivalency and flexibility of "clicked" multivalent glycoclusters.

    Science.gov (United States)

    Cecioni, Samy; Faure, Sophie; Darbost, Ulrich; Bonnamour, Isabelle; Parrot-Lopez, Hélène; Roy, Olivier; Taillefumier, Claude; Wimmerová, Michaela; Praly, Jean-Pierre; Imberty, Anne; Vidal, Sébastien

    2011-02-11

    The design of multivalent glycoconjugates has been developed over the past decades to obtain high-affinity ligands for lectin receptors. While multivalency frequently increases the affinity of a ligand for its lectin through the so-called "glycoside cluster effect", the binding profiles towards different lectins have been much less investigated. We have designed a series of multivalent galactosylated glycoconjugates and studied their binding properties towards two lectins, from plant and bacterial origins, to determine their potential selectivity. The synthesis was achieved through copper(I)-catalysed azide-alkyne cycloaddition (CuAAC) under microwave activation between propargylated multivalent scaffolds and an azido-functionalised carbohydrate derivative. The interactions of two galactose-binding lectins from Pseudomonas aeruginosa (PA-IL) and Erythrina cristagalli (ECA) with the synthesized glycoclusters were studied by hemagglutination inhibition assays (HIA), surface plasmon resonance (SPR) and isothermal titration microcalorimetry (ITC). The results obtained illustrate the influence of the scaffold's geometry on the affinity towards the lectin and also on the relative potency in comparison with a monovalent galactoside reference probe.

  17. Molecular Characterization of a New Lectin from the Marine Alga Ulva pertusa

    Institute of Scientific and Technical Information of China (English)

    ShengWANG; Fu-DiZHONG; Yong-JiangZHANG; Zu-JianWU; Qi-YingLIN; Lian-HuiXIE

    2004-01-01

    A new lectin, named UPL1, was purified from a green alga Ulvapertusa by an affinitychromatography on the bovine-thyroglobulin-Sepharose 4B column. The molecular mass of the algal lectinwas about 23 kD by SDS-PAGE, and it specifically agglutinated rabbit erythrocytes. The hemagglutinatingactivity for rabbit erythrocytes could be inhibited by bovine thyroglobulin and N-acetyl-D-glucosamine. Thelectin UPL1 required divalent cations for maintenance of its biological activity, and was heat-stable, and hadhigher activity within pH 6-8. The N-terminal amino acid sequence of the purified lectin was determined(P83209) and a set of degenerate primers were designed. The full-length cDNA of the lectin was cloned byrapid amplification ofcDNA ends (RACE) method (AY433960). Sequence analysis of upll indicated it was! 084 bp long, and encoded a premature protein of 203 amino acids. The N-terminal sequence of the matureUPL1 polypeptide started at amino acid 54 of the deduced sequence from the cDNA, indicating 53 aminoacids lost due to posttranslational modification. The primary structure of the Ulva pertusa lectin did not showamino acid sequence similarity with known plant and animal lectins. Hence, this protein may be the paradigmof a novel lectin family.

  18. Evaluation of Caesalpinia pulcherrima endospermic gum as affinity matrices for galactose-binding lectins interaction

    Directory of Open Access Journals (Sweden)

    Renata Chastinet Braga

    2011-04-01

    Full Text Available Lectins are proteins or glycoproteins able to bind, specifically and reversibly carbohydrates and glycoconjugates. Considering this ability, the utilization of Caesalpinia pulcherrima seeds polysaccharides as an affinity matrix was tested. The endospermic gum were solubilized in distinct concentrations of NaOH and treated with different amounts of epichlorohydrin (ECH forming affinity gels with variable capacity for interaction with galactose- binding lectins. The gel with an ECH/gum ration of 6.0mmol/g was selected as the best affinity matrix. The matrix presented different efficiencies in terms of isolating galactose-binding lectins. C. pulcherrima endospermic galactomannans were purified by ethanol precipitation and the purified galactomannan was crosslinked with the best formulation of gel. The Artocarpus incisa, Ricinus communis and Abrus precatorius lectins showed interactions of 11.5, 17.7 and 47.2mg of retained protein in 1g of gel, respectively; the Artocarpus integrifolia lectin showed the highest affinities (79.7mg/g. The heamaglutination assays confirmed the activity and SDS-PAGE electrophoresis confirmed the isolation of the lectins in a single-step procedure.

  19. Crystal structure of Pterocarpus angolensis lectin in complex with glucose, sucrose, and turanose.

    Science.gov (United States)

    Loris, Remy; Imberty, Anne; Beeckmans, Sonia; Van Driessche, Edilbert; Read, John S; Bouckaert, Julie; De Greve, Henri; Buts, Lieven; Wyns, Lode

    2003-05-02

    The crystal structure of the Man/Glc-specific seed lectin from Pterocarpus angolensis was determined in complex with methyl-alpha-d-glucose, sucrose, and turanose. The carbohydrate binding site contains a classic Man/Glc type specificity loop. Its metal binding loop on the other hand is of the long type, different from what is observed in other Man/Glc-specific legume lectins. Glucose binding in the primary binding site is reminiscent of the glucose complexes of concanavalin A and lentil lectin. Sucrose is found to be bound in a conformation similar as seen in the binding site of lentil lectin. A direct hydrogen bond between Ser-137(OG) to Fru(O2) in Pterocarpus angolensis lectin replaces a water-mediated interaction in the equivalent complex of lentil lectin. In the turanose complex, the binding site of the first molecule in the asymmetric unit contains the alphaGlc1-3betaFruf form of furanose while the second molecule contains the alphaGlc1-3betaFrup form in its binding site.

  20. Screening of lectins from South American plants used as affinity ligands to purify rhEPO

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    G.I. Amadeo

    2003-03-01

    Full Text Available Two groups of isoforms of rhEPO, at a concentration of 300 µg/ml, were tested as putative inhibitors of the lectinic hemagglutination reaction in order to obtain affinity ligand(s for hormone purification: groups I (pI: 3.80; 3.89; 3.95; 4.07, 4.15 and 4.26 and groups II (pI: 4.15, 4.26; 4.38; 4.51; 4.72 and 4.93 Crude extracts from the vegetable materials Abrus precatorious (Abrin, Artocarpus incisa (Frutalin, Artocarpus integrifolia (Jacalin, Canavalia ensiformes (ConA, Canavalia brasiliensis (Conbr, Cratylia floribunda, Dioclea altissima (DAL, Dioclea grandiflora (DGL, Erythrina vellutina (EVL, Erythrina cristagalli, Lutaelburgia auriculata (lectin not fully characterized yet, Lycopersicum esculentum (LEA, Phaseolus vulgaris (PHA, Ricinus communis (Ricin and Triticum vulgaris (WGA were used. Only some of the galactose-specific lectins and the GlcNAc-specific lectins showed rapid full inhibition of the hemagglutination reaction for the less acidic isoforms and the total isoforms of rhEPO, respectively. On this basis, the selected lectins were purified by affinity chromatoghraphy and covalently coupled to cyanogen bromide activated Sepharose® (Amersham-Pharmacia. CHO.K1 cell culture supernatant containing rhEPO was loaded onto the lectin resins and the recoveries were calculated by using specific elutions.

  1. Isolation and Partial Characterization of a New Lectin from Seeds of the Greater Celandine (Chelidonium majus) 1

    Science.gov (United States)

    Peumans, Willy J.; De Ley, Marc; Stinissen, Hetty M.; Broekaert, Willem F.

    1985-01-01

    Seeds of the greater celandine (Chelidonium majus L.) contain a lectin which could be isolated using a combination of affinity chromatography on chitin and ion exchange chromatography on sulphopropyl-Sephadex. The purified lectin was partially characterized with respect to its biochemical and physicochemical properties. It is a small dimeric protein composed of two different subunits of Mr 9,500 and 11,500, respectively. Its amino acid composition is typified by high contents of glycine and cysteine. No covalently bound carbohydrate could be detected. Hapten inhibition experiments indicated that the lectin exhibits specificity towards oligomers of N-acetylglucosamine, the potency of inhibition increasing with chain length up to four residues. The greater celandine lectin is the first lectin to be isolated from a species belonging to the plant family Papaveraceae (poppy family). Although it represents a new type of plant lectin, resemblances to phytohemaglutinins from diverse taxonomic origin are obvious. Images Fig. 2 PMID:16664249

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

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    Mirandeli Bautista

    2011-03-01

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

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

    Science.gov (United States)

    Alen'kina, S A; Nikitina, V E

    2015-01-01

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

  4. Differential binding properties of Gal/GalNAc specific lectins available for characterization of glycoreceptors.

    Science.gov (United States)

    Wu, A M; Song, S C; Sugii, S; Herp, A

    1997-01-01

    Differentiating the binding properties of applied lectins should facilitate the selection of lectins for characterization of glycoreceptors on the cell surface. Based on the binding specificities studied by inhibition assays of lectin-glycan interactions, over twenty Gal and/or GalNAc specific lectins have been divided into eight groups according to their specificity for structural units (lectin determinants), which are the disaccharide as all or part of the determinants and of GalNAc alpha 1-->Ser (Thr) of the peptide chain. A scheme of codes for lectin determinants is illustrated as follows: (1) F (GalNAc alpha 1-->3GalNAc), Forssman specific disaccharide--Dolichos biflorus (DBL), Helix pomatia (HPL) and Wistaria floribunda (WFL) lectins. (2) A (GalNAc alpha 1-->3 Gal), blood group A specific disaccharide--Codium fragile subspecies tomentosoides (CFT), Soy bean (SBL), Vicia villosa-A4 (VVL-A4), and Wistaria floribunda (WFL) lectins. (3) Tn (GalNAc alpha 1-->Ser (Thr) of the protein core)--Vicia villosa B4 (VVL-B4), Salvia sclarea (SSL), Maclura pomifera (MPL), Bauhinia purpurea alba (BPL) and Artocarpus integrifolia (Jacalin, AIL). (4) T (Gal beta 1-->3GalNAc), the mucin type sugar sequences on the human erythrocyte membrane(T alpha), T antigen or the disaccharides at the terminal nonreducing end of gangliosides (T beta)--Peanut (PNA), Bauhinia purpurea alba (BPL), Maclura pomifera (MPL), Sophora japonica (SJL), Artocarpus lakoocha (Artocarpin) lectins and Abrus precatorius agglutinin (APA).(5) I and II (Gal beta 1-->3(4)GlcNAc)--the disaccharide residue at the nonreducing end of the carbohydrate chains derived from either N- or O-glycosidic linkage--Ricinus communis agglutinin (RCA1), Datura stramonium (TAL, Thorn apple), Erythrina cristagalli (ECL, Coral tree), and Geodia cydonium (GCL). (6) B (Gal alpha 1-->3Gal), human blood group B specific disaccharide--Griffonia(Banderiaea) simplicifolia B4 (GSI-B4). (7) E (Gal alpha 1-->4Gal), receptors for pathogenic E

  5. Anti-inflammatory effect of glucose—mannose binding lectins isolated from Brazilian beans

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    A. M. S. Assreuy

    1997-01-01

    Full Text Available Selectins are essential for leukocyte recruitment in inflammation. Because of a lectin domain present in the selectin structure, we investigated the anti-inflammtory activity of six mannose–glucose binding lectins from brazilian beans: Dioclea guianensis-DguiL; D. grandiflora-DgL; Cratylia floribunda-CfL; D. violacea-D.vL; D. virgata-DvirL and Canavalia brasiliensis-ConBr. The lectins were injected intravenously (i.v. into rats (0.1 and 1.0 mg/kg; 30 min before irritants and its activities compared to E. coli endotoxin (LPS,30 μg/kg i.v.. Three lectins (DvL, CfL and DguiL, although less intense than LPS, inhibited the neutrophil migration induced by carrageenan (Cg, 300 μg in a dose-dependent manner (0.1 and 1.0 mg/kg. DvL activity was reversed by 0.1 M α-D-methyl-mannoside (α-CH3, but not by 0.1 M α-D-galactose. The fMLP (44 ng-induced neutrophil migration was also reduced by these lectins. Endotoxin contamination of lectin samples could be excluded since α-CH3 treatment reversed the DvL effect, but did not modify LPS inhibitory activity. Carrageenan (300 μg-induced paw oedema was also reduced by LPS or lectin treatments. Conversely, none of the tested lectins inhibited dextran (Dex, 300 μg-induced paw oedema, a classical leukocyte independent model, or zymosan (Zy, 1.0 mg-induced peritonitis and paw oedema. LPS showed no effect upon Dex-induced paw oedema and barely reduced (25% the oedematogenic effects of zymosan. As proposed for LPS, the lectin inhibitory activity was better observed on neutrophil-mediated inflammatory reactions. We speculate that the plant lectin antiinflammatory activity is probably due to a competitive blockage of a common leukocyte and/or endothelial selectin carbohydrate ligand.

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

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    Ram Sarup Singh

    Full Text Available 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

  7. Surface plasmon resonance for real-time study of lectin-carbohydrate interactions for the differentiation and identification of glycoproteins.

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    Safina, Gulnara; Duran, Iu Benet; Alasel, Mohammed; Danielsson, Bengt

    2011-06-15

    A study of specific interactions between lectins and glycoproteins has been carried out using surface plasmon resonance (SPR) in a flow-injection mode. Lectins were covalently immobilised on the surfaces of the microfluidic sensor chip via amine coupling and serum glycoproteins were injected into the flow channels. Specific lectin-glycoprotein interactions caused the shift of refractive index proportional to the mass concentration accumulated on the channel surface. Lectins showed different affinity to the tested glycoproteins and each glycoprotein displayed its own lectin-binding pattern. It is possible to distinguish and identify even glycoproteins with similar sugar structures by simple and quick screening. The working conditions of the assay were optimised. The lectin-based SPR made it possible to carry out the label-free detection of glycoproteins within a broad concentration range with a good linearity. Regeneration conditions for the surface of the sensor chip were found and optimised. Combination of 10mM HCl and 10mM glycine-HCl (pH 2.5) removes the bound glycoproteins from the lectin surface without damaging it. The kinetic and affinity parameters of lectin-glycoprotein binding were evaluated. The proposed method was tested on human glycosylated serum. Combination of the lectin panel with SPR is suitable both for specific screening and for sensitive assay of serum glycoproteins.

  8. Crystallization and preliminary X-ray diffraction analysis of HML, a lectin from the red marine alga Hypnea musciformis

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    Nagano, Celso S.; Gallego del Sol, Francisca [Instituto de Biomedicina de Valencia, CSIC, Valencia (Spain); Cavada, Benildo S.; Nascimento, Kyria Santiago Do [Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza, CE 60451-970 (Brazil); Nunes, Eudismar Vale; Sampaio, Alexandre H. [Laboratorio de Bioquímica Marinha, Departamento de Engenharia de Pesca, Universidade Federal do Ceará, Fortaleza, CE 60451-970 (Brazil); Calvete, Juan J., E-mail: jcalvete@ibv.csic.es [Instituto de Biomedicina de Valencia, CSIC, Valencia (Spain)

    2005-11-01

    The crystallization and preliminary X-ray diffraction analysis of a red marine alga lectin isolated from H. musciformis is reported. HML, a lectin from the red marine alga Hypnea musciformis, defines a novel lectin family. Orthorhombic crystals of HML belonging to space group P2{sub 1}2{sub 1}2{sub 1} grew within three weeks at 293 K using the hanging-drop vapour-diffusion method. A complete data set was collected at 2.4 Å resolution. HML is the first marine alga lectin to be crystallized.

  9. PURIFICATION AND CHARACTERIZATION OF A NEW MANNOSE-SPECIFIC LECTIN FROM Hyacinthella аcutiloba K. Perss.

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    V. O. Antonyuk

    2013-06-01

    Full Text Available A new lectin with 6.5 mg/kg yield was purified from fresh bulb Hyacinthella аcutiloba K. Perss. by combination of affinity chromathography on yeast mannan and by ion exchange chromatography on DEAE-toyopearl. The best lectin inhibitor among tested mono- and disaccharides was D-turanose (Glcp ?1-3 Fruf. Very powerful inhibitor of lectin activity was yeast mannan. The lectin revealed weak affinity to ?-methyl-Dmannoside, D-fructose and 2-acetamido-D-galactopyranoside. The lectin interacted also with pig liver glycogen, starch and mannose-containing glycoproteins (ovoalbumin, ovomucoid and calf thyroglobulin, but don’t interacted with horsera dish peroxidase and calf intestine alkaline phosphatase. According to electrophoresis, in 20% SDS-PAAG containing SDS-Na the lectin consists with subunits of molecular weight 12 kDa. Molecular weight of the lectin is 48 kDa according to gelchromatography on Toyopearl HW-55. The lectin agglutinated best of all rabbit erythrocytes and worse agglutinated guinea-pig, very weak — rat erythrocytes and did not agglutinate human and goat erythrocytes. After dialysis against 1% EDTA sodium salt solution the lectin did not lose hemaglutinating activity and endured heating to +65 °C during one hour.

  10. Activation of dendritic cells by the Gal-lectin of Entamoeba histolytica drives Th1 responses in vitro and in vivo.

    Science.gov (United States)

    Ivory, Catherine P A; Chadee, Kris

    2007-02-01

    Amebiasis is a human disease caused by the protozoan intestinal parasite Entamoeba histolytica. Vaccine development has focused on the parasite's surface galactose-N-acetyl-D-galactosamine inhibitable lectin (Gal-lectin) as a protective antigen. The Gal-lectin is immunogenic and has been shown to induce Th1 cytokines in vitro and in vivo. The immunological basis of the protective immune response elicited by the Gal-lectin is unknown. In this study, we investigated the response of BALB/c bone marrow-derived DC to E. histolytica Gal-lectin. Incubation of immature DC with Gal-lectin resulted in activation and maturation after 24 h. FACS analysis demonstrated an up-regulation of DC maturation markers CD80, CD86, CD40 and MHC class II upon exposure to Gal-lectin. The Gal-lectin also induced DC production of IL-12, indicating a Th1 response. Gal-lectin-activated DC were able to stimulate T cell proliferation in an allogeneic mixed leukocyte reaction and adoptive transfer of Gal-lectin-treated DC into naïve mice resulted in IFN-gamma-producing Gal-lectin-sensitized T cells. The activation of DC by Gal-lectin was mediated by MAPK and NF-kappaB. These findings indicate that E. histolytica Gal-lectin is a potent vaccine antigen capable of directly initiating DC maturation and activation characterized by Th1 cytokine production.

  11. A glucuronic acid binding leguminous lectin with mitogenic activity toward mouse splenocytes.

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    Chan, Yau Sang; Wong, Jack Ho; Ng, Tzi Bun

    2011-02-01

    A dimeric 64-kDa lectin was purified from seeds of French bean (Phaseolus vulgaris) cultivar number 1. The purification protocol entailed Q-Sepharose, Affi-gel blue gel, Mono S and Superdex 75. The lectin-enriched fraction was adsorbed on Q-Sepharose and Affi-gel blue gel and desorbed using 1M NaCl in the starting buffer. Hemagglutinating activity was adsorbed on Mono S and eluted with a linear 0.3-1 M NaCl gradient. Gel filtration on Superdex 75 yielded a single absorbance peak which appeared as a single 32-kDa in sodium dodecyl sulfate poylacylamide gel electrophoresis. Full hemagglutinating activity was observed when the lectin was exposed to a pH ranging from 3 to 11. About 50% activity remained at pH 12, and about 25% at pH 0 to pH 2. Activity was totally abolished at pH 13-14. The activity was completely preserved when the ambient temperature was 20 °C-60 °C. However, only 50% and 12.5% of the activity remained at 65 °C and 70 °C, respectively. Activity was barely discernible at 75 °C and completely abrogated at and above 80 °C. Hemagglutinating activity of the lectin was inhibited by glucuronic acid. Maximum mitogenic activity of the lectin toward murine splenocytes occurred at a lectin concentration of 0.488 µM. The mitogenic activity was nearly eliminated in the presence of 250 mM glucuronic acid. The lectin did not exhibit antiproliferative activity toward hepatoma (HepG2) cells, breast cancer (MCF7) cells, and nasopharynegeal carcinoma CNE stage 1 and stage 2 cells. It was also devoid of significant anti-HIV reverse transcriptase activity.

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

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    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

  13. An unusual anti-H lectin inhibited by milk from individuals with the Bombay phenotype.

    Science.gov (United States)

    Joshi, S R; Vasantha, K; Robb, J S

    2005-01-01

    There are several lectins with anti-H specificity but few of them serve as useful reagents. An anti-H lectin, extracted from the seeds of the plant Momordica dioica Roxb. ex willd., was tested for its hemagglutination and inhibition properties, using standard serologic methods and panel RBCs, serum, saliva, milk, and oligosaccharides purified from milk. The extract displayed strongest agglutination with group O RBCs and was weakest with group A1B RBCs in a spectrum of O>A2>B>A2B>A1>A1B; the extract failed to react with the RBCs from 25 individuals with the Bombay (Oh) phenotype and was inhibited by H secretor saliva, hence it was characterized as anti-H. However, its inhibition by milk samples from five mothers with the Bombay phenotype called into question its specificity as anti-H. The lectin reacted as strongly with group O ii (adult) RBCs as with normal OI RBCs, ruling out its specificity as anti-HI. Hemagglutination inhibition was observed with 2'-fucosyllactose (Type 2 H) and lacto-N-fucopentose-I (Type 1 H), suggesting that the binding of the lectin had preference for H structures. However, inhibition by N-acetyllactosamine, lacto-Ntetraose, and lacto-N-neotetraose suggested that the lectin also recognized unsubstituted terminal beta-linked galactose units. The hemagglutinin property in the present lectin showed an unusual anti-H specificity. The lectin was inhibited by milk from Bombay phenotype individuals and certain milk oligosaccharides not specific for the H antigen.

  14. Binding of the blood group-reactive lectins to human adult kidney specimens.

    Science.gov (United States)

    Laitinen, L; Juusela, H; Virtanen, I

    1990-01-01

    The binding of a panel of blood group-reactive lectins to frozen sections of human kidney was studied with a special emphasis on reactivity with endothelia and basement membranes. The blood group A-reactive lectins, all specific for alpha-D-N-acetylgalactosamine (GalNAc), Helix aspersa (HAA), Helix pomatia (HPA), and Griffonia simplicifolia I-A4 (GSA-I-A4) agglutinins bound to the endothelium in specimens with blood groups A and AB. In other samples, these lectins reacted predominantly with tubular basement membranes, as well as with certain tubules. Both Dolichos biflorus (DBA) and Vicia villosa agglutinins (VVA), reported to react with blood group A1 substance, failed to reveal endothelia in most specimens, but bound differently to tubules in all blood groups. The blood group B-reactive lectins, specific for alpha-D-galactose (alpha-Gal) or GalNAc, respectively, GSA-I-B4 and Sophora japonica agglutinin (SJA), bound to the endothelia in specimens from blood group B or AB and in other specimens bound only to certain tubules. Among the blood group O-reactive lectins, specific for alpha-L-fucose (Fuc), Ulex europaeus I agglutinin (UEA-I) conjugates, but not other lectins with a similar nominal specificity, bound strongly to endothelia in specimens with blood group O. The UEA-I conjugates bound distinctly more faintly to endothelia in specimens of other blood groups. The present results indicate that lectins, binding to defined blood group determinants, react with endothelia in specimens of the respective blood group status. Furthermore, they suggest that basement membranes and some tubules in the human kidney show a distinct heterogeneity in their expression of saccharide residues, related to their blood group status.

  15. Lectin binding patterns and carbohydrate mediation of sperm binding to llama oviductal cells in vitro.

    Science.gov (United States)

    Apichela, Silvana A; Valz-Gianinet, Jorge N; Schuster, Stefanie; Jiménez-Díaz, María A; Roldán-Olarte, Eugenia M; Miceli, Dora C

    2010-04-01

    Sperm binding to oviductal epithelium would be involved in sperm reservoir formation in the utero tubal junction (UTJ). Although in other mammals sperm-oviduct interaction has been proved to be mediated by carbohydrate-recognition mechanisms, the factors implicated in the sperm adhesion to oviductal epithelium of llama are still unknown. In order to assess the role of carbohydrates present in the mucosa surface, we examined the distribution of glycoconjugates in the llama oviduct by confocal lectin-histochemistry. Mannosyl, glucosyl, N-acetylglucosaminyl, galactosyl, N-acetylgalactosaminyl and sialic acid residues were detected in the oviductal mucose glycocalyx. By incubation of UTJ oviductal explants with LCA, DBA, UEA-1 or PNA lectin previous to co-culture with sperm, we observed a significant decrease in sperm binding only with LCA lectin. In the mucosa surface there were numerous d-glucosyl and D-manosyl residues, which were spotted by this lectin. Probably, this fact promotes the whole covering of the oviduct luminal surface by the sugar-lectin complex, preventing sperm access and adhesion of further residues. However, sperm incubation with mannose or glucose does not significantly prevent binding, which means that glucose and mannose would not be involved in a specific sperm-oviduct interaction. On the other hand, we observed a high reduction in sperm binding to UTJ explants with N-acetylgalactosamine and galactose (pllama sperm have lectin-like molecules in their surface, as is the case in other mammals. Probably, these lectin-like molecules, by means of N-acetylgalactosamine and galactose recognition, could link the sperm to the oviductal mucosa with the purpose of forming storing sites in the UTJ. Our results support the idea that more than one carbohydrate could participate in sperm reservoir formation in the llama UTJ oviductal segment.

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

    Science.gov (United States)

    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

  17. The Jacob2 lectin of the Entamoeba histolytica cyst wall binds chitin and is polymorphic.

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    Sudip K Ghosh

    2010-07-01

    Full Text Available The infectious and diagnostic form of Entamoeba histolytica (Eh, cause of amebic dysentery and liver abscess, is the quadranucleate cyst. The cyst wall of Entamoeba invadens (Ei, a model for Eh, is composed of chitin fibrils and three sets of chitin-binding lectins that cross-link chitin fibrils (multivalent Jacob lectins, self-aggregate (Jessie lectins, and remodel chitin (chitinase. The goal here was to determine how well the Ei model applies to Entamoeba cysts from humans.An Eh Jacob lectin (EhJacob2 has three predicted chitin-binding domains surrounding a large, Ser-rich spacer. Recombinant EhJacob2 made in transfected Eh trophozoites binds to particulate chitin. Sequences of PCR products using primers flanking the highly polymorphic spacer of EhJacob2 may be used to distinguish Entamoeba isolates. Antibodies to the EhJacob2, EhJessie3, and chitinase each recognize cyst walls of clinical isolates of Entamoeba. While numerous sera from patients with amebic intestinal infections and liver abscess recognize recombinant EhJacob1 and EhJessie3 lectins, few of these sera recognize recombinant EhJacob2.The EhJacob2 lectin binds chitin and is polymorphic, and Jacob2, Jessie3, and chitinase are present in cyst walls of clinical isolates of Entamoeba. These results suggest there are substantial similarities between cysts of the human pathogen (Eh and the in vitro model (Ei, even though there are quantitative and qualitative differences in their chitin-binding lectins.

  18. Large-Scale Gene Disruption in Magnaporthe oryzae Identifies MC69, a Secreted Protein Required for Infection by Monocot and Dicot Fungal Pathogens

    Science.gov (United States)

    Saitoh, Hiromasa; Fujisawa, Shizuko; Mitsuoka, Chikako; Ito, Akiko; Hirabuchi, Akiko; Ikeda, Kyoko; Irieda, Hiroki; Yoshino, Kae; Yoshida, Kentaro; Matsumura, Hideo; Tosa, Yukio; Win, Joe; Kamoun, Sophien; Takano, Yoshitaka; Terauchi, Ryohei

    2012-01-01

    To search for virulence effector genes of the rice blast fungus, Magnaporthe oryzae, we carried out a large-scale targeted disruption of genes for 78 putative secreted proteins that are expressed during the early stages of infection of M. oryzae. Disruption of the majority of genes did not affect growth, conidiation, or pathogenicity of M. oryzae. One exception was the gene MC69. The mc69 mutant showed a severe reduction in blast symptoms on rice and barley, indicating the importance of MC69 for pathogenicity of M. oryzae. The mc69 mutant did not exhibit changes in saprophytic growth and conidiation. Microscopic analysis of infection behavior in the mc69 mutant revealed that MC69 is dispensable for appressorium formation. However, mc69 mutant failed to develop invasive hyphae after appressorium formation in rice leaf sheath, indicating a critical role of MC69 in interaction with host plants. MC69 encodes a hypothetical 54 amino acids protein with a signal peptide. Live-cell imaging suggested that fluorescently labeled MC69 was not translocated into rice cytoplasm. Site-directed mutagenesis of two conserved cysteine residues (Cys36 and Cys46) in the mature MC69 impaired function of MC69 without affecting its secretion, suggesting the importance of the disulfide bond in MC69 pathogenicity function. Furthermore, deletion of the MC69 orthologous gene reduced pathogenicity of the cucumber anthracnose fungus Colletotrichum orbiculare on both cucumber and Nicotiana benthamiana leaves. We conclude that MC69 is a secreted pathogenicity protein commonly required for infection of two different plant pathogenic fungi, M. oryzae and C. orbiculare pathogenic on monocot and dicot plants, respectively. PMID:22589729

  19. Large-scale gene disruption in Magnaporthe oryzae identifies MC69, a secreted protein required for infection by monocot and dicot fungal pathogens.

    Directory of Open Access Journals (Sweden)

    Hiromasa Saitoh

    Full Text Available To search for virulence effector genes of the rice blast fungus, Magnaporthe oryzae, we carried out a large-scale targeted disruption of genes for 78 putative secreted proteins that are expressed during the early stages of infection of M. oryzae. Disruption of the majority of genes did not affect growth, conidiation, or pathogenicity of M. oryzae. One exception was the gene MC69. The mc69 mutant showed a severe reduction in blast symptoms on rice and barley, indicating the importance of MC69 for pathogenicity of M. oryzae. The mc69 mutant did not exhibit changes in saprophytic growth and conidiation. Microscopic analysis of infection behavior in the mc69 mutant revealed that MC69 is dispensable for appressorium formation. However, mc69 mutant failed to develop invasive hyphae after appressorium formation in rice leaf sheath, indicating a critical role of MC69 in interaction with host plants. MC69 encodes a hypothetical 54 amino acids protein with a signal peptide. Live-cell imaging suggested that fluorescently labeled MC69 was not translocated into rice cytoplasm. Site-directed mutagenesis of two conserved cysteine residues (Cys36 and Cys46 in the mature MC69 impaired function of MC69 without affecting its secretion, suggesting the importance of the disulfide bond in MC69 pathogenicity function. Furthermore, deletion of the MC69 orthologous gene reduced pathogenicity of the cucumber anthracnose fungus Colletotrichum orbiculare on both cucumber and Nicotiana benthamiana leaves. We conclude that MC69 is a secreted pathogenicity protein commonly required for infection of two different plant pathogenic fungi, M. oryzae and C. orbiculare pathogenic on monocot and dicot plants, respectively.

  20. Structural and functional characterization of the GalNAc/Gal-specific lectin from the phytopathogenic ascomycete Sclerotinia sclerotiorum (Lib.) de Bary.

    Science.gov (United States)

    Candy, Laure; Van Damme, Els J M; Peumans, Willy J; Menu-Bouaouiche, Laurence; Erard, Monique; Rougé, Pierre

    2003-08-22

    The lectin found in mycelium and sclerotes of the phytopathogenic fungus Sclerotinia sclerotiorum is a homodimer consisting of two identical non-covalently bound subunits of 16,000 Da. CD spectra analysis revealed that the S. sclerotiorum agglutinin (SSA) contains predominantly beta-sheet structures. SSA exhibits specificity towards GalNAc whereby the hydroxyls at positions 4 and 6 of the pyranose ring play a key role in the interaction with simple sugars. The carbohydrate-binding site of SSA can also accommodate disaccharides. The N-terminal sequence of SSA shares no significant similarity with any other protein except a lectin from the Sclerotiniaceae species Ciborinia camelliae. A comparison of SSA and the lectins from C. camelliae and some previously characterized lectins indicates that the Sclerotiniaceae lectins form a homogeneous family of fungal lectins. This newly identified lectin family, which is structurally unrelated to any other family of fungal lectins, is most probably confined to the Ascomycota.

  1. A lectin with highly potent inhibitory activity toward breast cancer cells from edible tubers of Dioscorea opposita cv. nagaimo.

    Directory of Open Access Journals (Sweden)

    Yau Sang Chan

    Full Text Available A 70-kDa galactose-specific lectin was purified from the tubers of Dioscorea opposita cv. nagaimo. The purification involved three chromatographic steps: anion exchange chromatography on a Q-Sepharose column, FPLC-anion exchange chromatography on a Mono Q column, and FPLC-gel filtration on a Superdex 75 column. The purified nagaimo lectin presented as a single 35-kDa band in reducing SDS-PAGE while it exhibited a 70-kDa single band in non-reducing SDS-PAGE suggesting its dimeric nature. Nagaimo lectin displayed moderate thermostability, retaining full hemagglutinating activity after heating up to 62°C for 30 minutes. It also manifested stability over a wide pH range from pH 2 to 13. Nagaimo lectin was a galactose-specific lectin, as evidenced by binding with galactose and galactose-containing sugars such as lactose and raffinose. The minimum concentration of galactose, lactose and raffinose required to exert an inhibitory effect on hemagglutinating activity of nagaimo lectin was 20 mM, 5 mM and 40 mM, respectively. Nagaimo lectin inhibited the growth of some cancer cell lines including breast cancer MCF7 cells, hepatoma HepG2 cells and nasopharyngeal carcinoma CNE2 cells, with IC(50 values of 3.71 µM, 7.12 µM and 19.79 µM, respectively, after 24 hour treatment with nagaimo lectin. The induction of phosphatidylserine externalization and mitochondrial depolarization indicated that nagaimo lectin evoked apoptosis in MCF7 cells. However, the anti-proliferative activity of nagaimo lectin was not blocked by application of galactose, signifying that the activity was not related to the carbohydrate binding specificity of the lectin.

  2. Electron microscopic demonstration of lectin binding sites in the taste buds of the European catfish Silurus glanis (Teleostei).

    Science.gov (United States)

    Witt, M; Reutter, K

    1990-01-01

    Taste buds in the European catfish Silurus glanis were examined with electron microscopic lectin histochemistry. For detection of carbohydrate residues in sensory cells and adjacent epithelial cells, gold-, ferritin- and biotin-labeled lectins were used. A post-embedding procedure carried out on tissue sections embedded in LR-White was applied to differentiate between the sensory cells: The lectins from Helix pomatia (HPA) and Triticum vulgare (WGA) bound to N-acetyl-galactosamine and to N-acetylglucosamine residues occurring especially in vesicles of dark sensory cells. This indicates a secretory function of these cells. Most light sensory cells--with some exceptions, probably immature cells--, are HPA-negative. The mucus of the receptor field and at the top of the adjacent epithelial cells was strongly HPA-positive. Pre-embedding studies were performed in order to obtain information about the reaction of the mucus with lectins under supravital conditions. The mucus of the taste bud receptor field exhibited intensive binding to WGA, but not to the other lectins tested. Most lectins bound predominantly to the surface mucus of the nonsensory epithelium and to the marginal cells close to the receptor field. The strong lectin binding to mucins and the relatively weak lectin binding to cell surface membranes in pre-embedding studies suggest that the mucus possibly serves as a barrier which is passed selectively only by a small amount of lectins or lectin-carbohydrate complexes. Lectin-carbohydrate interactions may play a role in recognition phenomena on the plasmalemmata of the taste bud sensory cells. Recognition processes directed to bacteria or viruses should be considered as well.

  3. Targeting C-type Lectin Receptors for Cancer Immunity

    Directory of Open Access Journals (Sweden)

    Huimin eYan

    2015-08-01

    Full Text Available C-type lectin receptors (CLRs are a large family of soluble and trans-membrane pattern recognition receptors that are widely and primarily expressed on myeloid cells. CLRs are important for cell-cell communication and host defense against pathogens through the recognition of specific carbohydrate structures. Similar to a family of Toll-like receptors (TLRs, CLRs signaling are involved in the various steps for initiation of innate immune responses and promote secretion of soluble factors such as cytokines and interferons, Moreover, CLRs contribute to endocytosis and antigen-presentation, thereby fine-tune adaptive immune responses. In addition, there may also be a direct activation of acquired immunity. On the other hand, glycans, such as mannose structures, Lewis-type antigens or GalNAc are components of tumor antigens and ligate CLRs, leading to immunoregulation. Therefore agonists or antagonists of CLRs signaling are potential therapeutic reagents for cancer immunotherapy. We aim to overview the current knowledge of CLRs signaling and the application of their ligands on tumor-associating immune response.

  4. Entamoeba histolytica: Adhesins and Lectins in the Trophozoite Surface

    Directory of Open Access Journals (Sweden)

    Magdalena Aguirre García

    2015-02-01

    Full Text Available Entamoeba histolytica is the causative agent of amebiasis in humans and is responsible for 100,000 deaths annually, making it the third leading cause of death due to a protozoan parasite. Pathogenesis appears to result from the potent cytotoxic activity of the parasite, which kills host cells within minutes. Although the mechanism is unknown, it is well established to be contact-dependent. The life cycle of the parasite alternates with two forms: the resistant cyst and the invasive trophozoite. The adhesive interactions between the parasite and surface glycoconjugates of host cells, as well as those lining the epithelia, are determinants for invasion of human tissues, for its cytotoxic activity, and finally for the outcome of the disease. In this review we present an overview of the information available on the amebic lectins and adhesins that are responsible of those adhesive interactions and we also refer to their effect on the host immune response. Finally, we present some concluding remarks and perspectives in the field.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-08-08

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

  6. Contribution of the carbohydrate-binding ability of Vatairea guianensis lectin to induce edematogenic activity.

    Science.gov (United States)

    Marques, Gabriela F O; Osterne, Vinicius J S; Almeida, Livia M; Oliveira, Messias V; Brizeno, Luiz A C; Pinto-Junior, Vanir R; Santiago, Mayara Q; Neco, Antonio H B; Mota, Mario R L; Souza, Luiz A G; Nascimento, Kyria S; Pires, Alana F; Cavada, Benildo S; Assreuy, Ana M S

    2017-09-01

    Vatairea guianensis lectin (VGL), Dalbergiae tribe, is a N-acetyl-galactosamine (GalNAc)/Galactose (Gal) lectin previously purified and characterized. In this work, we report its structural features, obtained from bioinformatics tools, and its inflammatory effect, obtained from a rat paw edema model. The VGL model was obtained by homology with the lectin of Vatairea macrocarpa (VML) as template, and we used it to demonstrate the common characteristics of legume lectins, such as the jellyroll motif and presence of a metal-binding site in the vicinity of the carbohydrate-recognition domain (CRD). Protein-ligand docking revealed favorable interactions with N-acetyl-d-galactosamine, d-galactose and related sugars as well as several biologically relevant N- and O-glycans. In vivo testing of paw edema revealed that VGL induces edematogenic effect involving prostaglandins, interleukins and VGL CRD. Taken together, these data corroborate with previous reports showing that VGL interacts with N- and/or O-glycans of molecular targets, particularly in those presenting galactosides in their structure, contributing to the lectin inflammatory effect. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  7. Anti-tumor and anti-viral activities of Galanthus nivalis agglutinin (GNA)-related lectins.

    Science.gov (United States)

    Wu, Lei; Bao, Jin-Ku

    2013-04-01

    Galanthus nivalis agglutinin (GNA)-related lectin family, a superfamily of strictly mannose-binding specific lectins widespread among monocotyledonous plants, is well-known to possess a broad range of biological functions such as anti-tumor, anti-viral and anti-fungal activities. Herein, we mainly focused on exploring the precise molecular mechanisms by which GNA-related lectins induce cancer cell apoptotic and autophagic death targeting mitochondria-mediated ROS-p38-p53 apoptotic or autophagic pathway, Ras-Raf and PI3K-Akt anti-apoptotic or anti-autophagic pathways. In addition, we further discussed the molecular mechanisms of GNA-related lectins exerting anti-viral activities by blocking the entry of the virus into its target cells, preventing transmission of the virus as well as forcing virus to delete glycan in its envelope protein and triggering neutralizing antibody. In conclusion, these findings may provide a new perspective of GNA-related lectins as potential drugs for cancer and virus therapeutics in the future.

  8. Isolation, functional, and partial biochemical characterization of galatrox, an acidic lectin from Bothrops atrox snake venom

    Institute of Scientific and Technical Information of China (English)

    Elaine de Paula Mendonca-Franqueiro; Eliane Candiani Arantes; Marcelo Dias-Baruffi; Suely Vilela Sampaio; Raquel de Melo Alves-Paiva; Marco Aurélio Sartim; Daniel Roberto Callejon; Helder Henrique Paiva; Gilmara Ausech Antonucci; José César Rosa; Adélia Cristina Oliveira Cintra; Jo(a)o José Franco

    2011-01-01

    Snake venom lectins have been studied in regard to their chemical structure and biological functions. However, little is known about lectins isolated from Bothrops atrox snake venom. We report here the isolation and partial functional and biochemical characterization of an acidic glycanbinding protein called galatrox from this venom. This lectin was purified by affinity chromatography using a lactosyl-sepharose column, and its homogeneity and molecular mass were evaluated by high-performance liquid chromatography, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry. The purified galatrox was homogeneous and characterized as an acidic protein (pI 5.2) with a monomeric and dimeric molecular mass of 16.2 and 32.5 kDa, respectively. Alignment of N-terminal and internal amino acid sequences of galatrox indicated that this protein exhibits high homology to other C-type snake venom lectins. Galatrox showed optimal hemagglutinating activity at a concentration of 100 μg/ml and this effect was drastically inhibited by lactose, ethylenediaminetetraacetic acid, and heating, which confirmed galatrox's lectin activity. While galatrox failed to induce the same level of paw edema or mast cell degranulation as B. atrox crude venom, galatrox did alter cellular viability,which suggested that galatrox might contribute to venom toxicity by directly inducing cell death.

  9. Reverse lectin ELISA for detecting fucosylated forms of α1-acid glycoprotein associated with hepatocellular carcinoma

    Science.gov (United States)

    Stål, Per; Zenlander, Robin; Edenvik, Pia; Alexandersson, Catharina; Haglund, Mats; Rydén, Ingvar; Påhlsson, Peter

    2017-01-01

    Altered fucosylation of glycoproteins is associated with development of hepatocellular carcinoma (HCC). Lectins have been commonly used to assay changes in fucosylation of plasma glycoproteins. In the present study a recombinantly engineered form of the fucose binding lectin Aleuria aurantia (AAL) consisting of a single binding site for fucose (S2), was used to construct a reverse lectin ELISA method. Microtiter plates coated with the S2 lectin were used to capture glycoproteins from plasma samples followed by antibody detection of S2-bound fucosylated α1-acid glycoprotein (S2-bound AGP). The method was used to compare the level of S2-bound AGP in serum samples from a small cohort of patients with hepatitis, cirrhosis or HCC. Using the reverse S2 lectin ELISA it was shown that the levels of S2-bound AGP was significantly higher in HCC patients compared to non-cancer patients and that there was also a significant elevation of S2-bound AGP in HCC patients compared to cirrhosis patients. There was no correlation between the level of S2-bound AGP and total AGP concentration. The performance of S2-bound AGP in differentiating HCC from cirrhosis samples or hepatitis samples were compared to other markers. A combination of S2-bound AGP, α-fetoprotein and AGP concentration showed performances giving area under receiver operating curves of 0.87 and 0.95 respectively. PMID:28296934

  10. Purification and molecular cloning of a new galactose-specific lectin from Bauhinia variegata seeds

    Indian Academy of Sciences (India)

    Luciano S Pinto; Celso S Nagano; Taianá M Oliveira; Tales R Moura; Alexandre H Sampaio; Henri Debray; Vicente P Pinto; Odir A Dellagostin; Benildo S Cavada

    2008-09-01

    A new galactose-specific lectin was purified from seeds of a Caesalpinoideae plant, Bauhinia variegata, by affinity chromatography on lactose–agarose. Protein extracts haemagglutinated rabbit and human erythrocytes (native and treated with proteolytic enzymes), showing preference for rabbit blood treated with papain and trypsin. Among various carbohydrates tested, the lectin was best inhibited by D-galactose and its derivatives, especially lactose. SDS-PAGE showed that the lectin, named BVL, has a pattern similar to other lectins isolated from the same genus, Bauhinia purpurea agglutinin (BPA). The molecular mass of BVL subunit is 32 871 Da, determined by MALDI-TOF spectrometry. DNA extracted from B. variegata young leaves and primers designed according to the B. purpurea lectin were used to generate specific fragments which were cloned and sequenced, revealing two distinct isoforms. The bvl gene sequence comprised an open reading frame of 876 base pairs which encodes a protein of 291 amino acids. The protein carried a putative signal peptide. The mature protein was predicted to have 263 amino acid residues and 28 963 Da in size.

  11. Purification and molecular characterization of a sialic acid specific lectin from the phytopathogenic fungus Macrophomina phaseolina.

    Science.gov (United States)

    Bhowal, Jayati; Guha, Arun Kumar; Chatterjee, Bishnu Pada

    2005-09-05

    A lectin was isolated and purified from the culture filtrate of the plant pathogenic fungus Macrophomina phaseolina by a combination of ammonium sulfate precipitation, affinity chromatography on fetuin-Sepharose 4B and ion-exchange chromatography on DEAE-A 50. The lectin designated MPL was homogeneous by PAGE and HPLC and a monomeric protein with a molecular weight of approximately 34 kDa as demonstrated by SDS-PAGE. It is a glycoprotein and agglutinated human erythrocytes regardless of the human blood type. Neuraminidase treatment of erythrocytes reduced the agglutination activity of the lectin. It is thermally stable and exhibits maximum activity between pH 6 and 7.2. Its carbohydrate binding specificity was investigated both by hapten inhibition of hemagglutination and by enzyme-conjugated lectin inhibition assay. Although, M. phaseolina lectin bound sialic acid, it exhibited binding affinity towards neuraminyl oligosaccharides of N-linked glycoproteins, alpha-Neu5Ac-(2-->3)-beta-Gal-(1-->4)-GlcNAc being maximum.

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

    Science.gov (United States)

    Narahari, Akkaladevi; Swamy, Musti J

    2010-04-21

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

  13. Purification and molecular cloning of a new galactose-specific lectin from Bauhinia variegata seeds.

    Science.gov (United States)

    Pinto, Luciano S; Nagano, Celso S; Oliveira, Taianá M; Moura, Tales R; Sampaio, Alexandre H; Debray, Henri; Pinto, Vicente P; Dellagostin, Odir A; Cavada, Benildo S

    2008-09-01

    A new galactose-specific lectin was purified from seeds of a Caesalpinoideae plant, Bauhinia variegata, by affinity chromatography on lactose-agarose. Protein extracts haemagglutinated rabbit and human erythrocytes (native and treated with proteolytic enzymes), showing preference for rabbit blood treated with papain and trypsin. Among various carbohydrates tested, the lectin was best inhibited by D-galactose and its derivatives, especially lactose. SDS-PAGE showed that the lectin, named BVL, has a pattern similar to other lectins isolated from the same genus, Bauhinia purpurea agglutinin (BPA). The molecular mass of BVL subunit is 32 871 Da, determined by MALDI-TOF spectrometry. DNA extracted from B.variegata young leaves and primers designed according to the B. purpurea lectin were used to generate specific fragments which were cloned and sequenced, revealing two distinct isoforms. The bvl gene sequence comprised an open reading frame of 876 base pairs which encodes a protein of 291 amino acids. The protein carried a putative signal peptide. The mature protein was predicted to have 263 amino acid residues and 28 963 Da in size.

  14. Rheologic characterization of vegetal lectins by dissociation of induced erythrocyte agglutinates.

    Science.gov (United States)

    Rasia, R J; Valverde, J R; Gentils, M; Cauchois, C; Stoltz, J F

    1997-01-01

    Energy evolved from hemagglutination reaction or spent in dissociating erythrocyte agglutinates has been proved to be an excellent parameter for analyzing cell-cell interactions mediated by bridging molecules such as antibodies or lectins. We developed a new rheo-optical method to estimate the energy of dissociation of red blood cell agglutinates. In a Couette shear field agglutinates can be dissociated until a suspension of monodispersed cells is obtained. Intensity of light backscattered by suspended agglutinates increases during their mechanical dissociation. Variation of backscattered light intensity correlates with the energy spent in the process. The adhesive energy of erythrocyte agglutination induced by lectins has been estimated by applying this method. Two specific lectins (Dolichus Biflorus agglutinin and Ulex Europaeus agglutinin) and a new lectin obtained from Amarantus Cruentus seeds which specificity is unknown were studied. Results obtained in this work for Dolichus Biflorus lectin are comparable with values published by other authors. An asymptotic decrease of adhesive energy was observed when the mechanical dissociation was applied several times on the same sample. Our results suggest that the cell detachment is accompanied by the extraction of membrane receptors. This finding is consistent with results obtained by other authors.

  15. Optimized immobilization of lectins using self-assembled monolayers on polysilicon encoded materials for cell tagging.

    Science.gov (United States)

    Penon, Oriol; Siapkas, Dimitrios; Novo, Sergi; Durán, Sara; Oncins, Gerard; Errachid, Abdelhamid; Barrios, Lleonard; Nogués, Carme; Duch, Marta; Plaza, José Antonio; Pérez-García, Lluïsa

    2014-04-01

    Self-assembled monolayers (SAMs) have been used for the preparation of functional microtools consisting of encoded polysilicon barcodes biofunctionalized with proteins of the lectin family. These hybrid microtools exploit the lectins ability for recognizing specific carbohydrates of the cell membrane to give an efficient system for cell tagging. This work describes how the control of the methodology for SAM formation on polysilicon surfaces followed by lectin immobilization has a crucial influence on the microtool biofunction. Several parameters (silanization time, silane molar concentration, type of solvent or deposition methodology) have been studied to establish optimal function. Furthermore, silanes incorporating different terminal groups, such as aldehyde, activated ester or epoxide groups were tested in order to analyze their chemical coupling with the biomolecules, as well as their influence on the biofunctionality of the immobilized protein. Two different lectins - wheat germ agglutinin (WGA) and phytohemagglutinin (PHA-L) - were immobilized, because they have different and specific cell recognition behaviour and exhibit different cell toxicity. In this way we can assess the effect of intrinsic bulk toxicity with that of the cell compatibility once immobilized as well as the importance of cell affinity. A variety of nanometrical techniques were used to characterize the active surfaces, and lectin immobilization was quantified using ultraviolet-visible absorption spectroscopy (UV-vis) and optical waveguide light mode spectroscopy (OWLS). Once the best protocol was found, WGA and PHA were immobilized on polysilicon coded barcodes, and these microtools showed excellent cell tagging on living mouse embryos when WGA was used.

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

    Directory of Open Access Journals (Sweden)

    Carla eOliveira

    2014-08-01

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

  17. Purification and biological effects of a C-type lectin isolated from Bothrops moojeni

    Directory of Open Access Journals (Sweden)

    PSF Barbosa

    2010-01-01

    Full Text Available Snake venom proteins from the C-type lectin family have very distinct biological activities despite their highly conserved primary structure, which is homologous to the carbohydrate recognition region of true C-type lectins. We purified a lectin-like protein (BmLec from Bothrops moojeni venom and investigated its effect on platelet aggregation, insulin secretion, antibacterial activity, and isolated kidney cells. The BmLec was purified using two chromatographic steps: affinity chromatography and reverse phase high performance liquid chromatography (HPLC. BmLec showed a dose-dependent platelet aggregation and significantly decreased the bacterial growth rate in approximately 15%. During scanning electron microscopy, the profile of Xanthomonas axonopodis pv. passiflorae treated with lectin disclosed a high vesiculation and membrane rupture. BmLec induced a strong and significant increase in insulin secretion at 2.8 and 16.7 mM glucose concentrations, and this effect was seen in the presence of EGTA in both experiments. BmLec (10 µg/mL increased the perfusion pressure, renal vascular resistance and urinary flow. The glomerular filtration rate and percentages of sodium, potassium and chloride tubular transport were reduced at 60 minutes of perfusion. Renal alterations caused by BmLec were completely inhibited by indomethacin in all evaluated parameters. In conclusion, the C-type lectin isolated from Bothrops moojeni affected platelet aggregation, insulin secretion, antibacterial activity and isolated kidney function.

  18. The effect of Cratylia floribunda lectin on renal hemodynamics and ion transport

    Directory of Open Access Journals (Sweden)

    Alexandre Havt

    2015-09-01

    Full Text Available Lectins have been described as glycoproteins that reversibly and specifically bind to carbohydrates. Legume lectins isolated from the subtribe Diocleinae (Canavalia, Dioclea andCratylia are structurally homologous with respect to their primary structures. The Diocleinae lectins of Canavalia brasiliensis, Dioclea guianensis andCanavalia ensiformis have been shown to distinctly alter physiological parameters in isolated rat kidneys. Thus, the aim of this study was to investigate the effect of Cratylia floribunda lectin (CFL on renal hemodynamics and ion transport in rats. In isolated perfused kidneys, CFL (10 mg/mL, n=5 increased RPP, RVR and decreased %TK+, but did not change urinary flow, glomerular filtration rate, sodium or chloride tubular transport. In isolated perfused mesenteric bed, CFL (3 and 10 mg/mL/min; n=4 did not alter tissue basal tonus or tissue contraction by phenylephrine (1 mM/mL/min. In conclusion, the seed lectin of Cratylia floribunda increased renal hemodynamic parameters showing a kaliuretic effect. This effect could be of tubular origin, rather than a result from haemodynamic alterations.

  19. The lectin domains of polypeptide GalNAc-transferases exhibit carbohydrate-binding specificity for GalNAc: lectin binding to GalNAc-glycopeptide substrates is required for high density GalNAc-O-glycosylation

    DEFF Research Database (Denmark)

    Wandall, Hans H; Irazoqui, Fernando; Tarp, Mads Agervig;

    2007-01-01

    to the enzyme. We have previously shown that the lectin domain of GalNAc-T4 modulates its substrate specificity to enable unique GalNAc-glycopeptide specificities and that this effect is selectively inhibitable by GalNAc; however, direct evidence of carbohydrate binding of GalNAc-transferase lectins has......-T2). Both lectins exhibited specificity for binding of free GalNAc. Kinetic and time-course analysis of GalNAc-T2 demonstrated that the lectin domain did not affect transfer to initial glycosylation sites, but selectively modulated velocity of transfer to subsequent sites and affected the number......Initiation of mucin-type O-glycosylation is controlled by a large family of UDP GalNAc:polypeptide N-acetylgalactosaminyltransferases (GalNAc-transferases). Most GalNAc-transferases contain a ricin-like lectin domain in the C-terminal end, which may confer GalNAc-glycopeptide substrate specificity...

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

    NARCIS (Netherlands)

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

    2011-01-01

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

  1. Serum mannan-binding lectin-associated serine protease 2 levels in colorectal cancer: relation to recurrence and mortality

    DEFF Research Database (Denmark)

    Ytting, Henriette; Christensen, Ib Jarle; Thiel, Steffen;

    2005-01-01

    PURPOSE: Mannan-binding lectin-associated serine protease 2 (MASP-2) is a plasma protein involved in inflammatory processes. MASP-2 circulates in complex with the protein mannan-binding lectin (MBL) or ficolins, and is activated to recruit the complement system when MBL binds to its targets...

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

    Science.gov (United States)

    Vasconcelos, Mayron Alves; Arruda, Francisco Vassiliepe Sousa; Carneiro, Victor Alves; Silva, Helton Colares; Nascimento, Kyria Santiago; Sampaio, Alexandre Holanda; Cavada, Benildo; Teixeira, Edson Holanda; Henriques, Mariana

    2014-01-01

    This study aimed to evaluate the abilities of plant and algae lectins to inhibit planktonic growth and biofilm formation in bacteria and yeasts. Initially, ten lectins were tested on Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella oxytoca, Pseudomonas aeruginosa, Candida albicans, and C. tropicalis at concentrations of 31.25 to 250 μg/mL. The lectins from Cratylia floribunda (CFL), Vatairea macrocarpa (VML), Bauhinia bauhinioides (BBL), Bryothamnion seaforthii (BSL), and Hypnea musciformis (HML) showed activities against at least one microorganism. Biofilm formation in the presence of the lectins was also evaluated; after 24 h of incubation with the lectins, the biofilms were analyzed by quantifying the biomass (by crystal violet staining) and by enumerating the viable cells (colony-forming units). The lectins reduced the biofilm biomass and/or the number of viable cells to differing degrees depending on the microorganism tested, demonstrating the different characteristics of the lectins. These findings indicate that the lectins tested in this study may be natural alternative antimicrobial agents; however, further studies are required to better elucidate the functional use of these proteins. PMID:24982871

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

    Directory of Open Access Journals (Sweden)

    Yau Sang Chan

    2015-01-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

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

    NARCIS (Netherlands)

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

    2011-01-01

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

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

    DEFF Research Database (Denmark)

    Poulsen, Morten; Schrøder, Malene; Wilcks, Andrea

    2007-01-01

    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...... safety testing of genetically modified foods....

  7. Conformational study reveals amino acid residues essential for hemagglutinating and anti-proliferative activities of Clematis montana lectin

    National Research Council Canada - National Science Library

    Bangmin Lu Bin Zhang Wei Qi Yanan Zhu Yan Zhao Nan Zhou Rong Sun Jinku Bao Chuanfang Wu

    2014-01-01

    Clematis montana lectin (CML), a novel mannose-binding lectin purified from C. montana Buch.-Ham stem (Ranunculaceae), has been proved to have hemagglutinat- ing activity in rabbit erythrocytes and apoptosis-inducing activity in tumor cells...

  8. Salivary agglutinin is the major component in human saliva that modulates the lectin pathway of the complement system

    NARCIS (Netherlands)

    Gunput, S.T.G.; Wouters, D.; Nazmi, K.; Cukkemane, N.; Brouwer, M.; Veerman, E.C.I.; Ligtenberg, A.J.M.

    2016-01-01

    Saliva interacts with blood after mucosal damage or leakage of gingival crevicular fluid. Surface-adsorbed salivary agglutinin (SAG) activates the lectin pathway (LP) of the complement system via mannose-binding lectin, while SAG in solution inhibits complement activation. In the present study we

  9. Phenotype-associated lectin-binding profiles of normal and transformed blood cells: a comparative analysis of mannose- and galactose-binding lectins from plants and human serum/placenta.

    Science.gov (United States)

    Mann, K K; André, S; Gabius, H J; Sharp, J G

    1994-10-01

    Surface glycoconjugates of normal and transformed blood cells are commonly characterized by plant lectins. To infer physiological significance of protein-carbohydrate interactions, mammalian lectins are obviously preferable as research tools. So far, human serum lectins have not been used to assess their binding to immunophenotyped human normal or transformed blood cells. Thus, our study combines two groups of lectins with different specificity from plant and human sources. Besides concanavalin A (ConA) we have isolated the mannose-binding protein and serum amyloid P component from human serum. Especially the mannose-binding protein is believed to play a role in host defence against bacteria and yeast cells with unknown impact on normal and tumor cells. These three lectins establish the first group. In addition to the immunomodulatory mistletoe lectin, whose binding can elicit enhanced cytokine secretion from mononuclear blood cells, we included the beta-galactoside-binding lectin (14 kDa) from human placenta in the second group. The initial series of measurements was undertaken using two-color flow cytometry to determine the phenotype-associated binding (based on cluster designation; CD) of the lectins to blood and bone marrow cells from normal donors and the cell line CEM (T-lymphoblastoid), KG1-A (primitive myeloid leukemia) and Croco II (B-lymphoblastoid). Heterogeneity was apparent for each lectin in the CD-defined cell populations. Significant differences in binding were noted between Viscum album agglutinin (VAA) and other lectins for CD4+ cells from blood and between mannose-binding protein (MBP) and VAA versus 14 kDa, ConA and serum amyloid P component (SAP) for CD19+ cells from bone marrow.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Epidemiology of chronic wound patients and relation to serum levels of mannan-binding lectin

    DEFF Research Database (Denmark)

    Bitsch, Mikael; Laursen, Inga; Engel, Anne-Mari

    2009-01-01

    The aim of this study was to describe the epidemiology of chronic wounds in a large cohort of patients from a tertiary hospital out-patient clinic, and examine the significance of serum mannan-binding lectin for the occurrence and clinical presentation of such wounds. The study comprised 489...... consecutive patients with chronic foot and leg ulcers. A clinical classification of wound- aetiology was performed, and mannan-binding lectin was measured in the sera of patients and healthy controls. The patients presented with 639 wounds altogether; diabetic foot ulcers (309), venous leg ulcers (188......), arterial ulcers (109), and vasculitis (33). The mannan-binding lectin levels of patients with venous leg ulcer, alone or in combination with other types of wounds, differed significantly from the control group, and the frequency of values

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

    Directory of Open Access Journals (Sweden)

    Julieta Pérez-Giménez

    2009-01-01

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

  12. Evolutionary conservation of mannan-binding lectin (MBL) in bony fish

    DEFF Research Database (Denmark)

    Kania, Per Walter; Sørensen, Rasmus Reng; Koch, Claus

    2010-01-01

    characterized in the rainbow trout but so far no molecules of the lectin pathway have been identified. Based on the generally accepted idea of complement evolution, which predicts that the alternative pathway predates the two other pathways, and that the lectin pathway developed before the classical, we set out...... intestine and the liver. In the liver, we saw co-expression with mannan-binding lectin associated serine protease (MASP). The MBL homologues 2 and 3 (MBL-H2,3) were also found in the vascular system of the rainbow trout. By means of gel size exclusion chromatography of serum we found that MBL-H2......,3 oligomerized heterogeneously from monomers to tetramers of a trimeric collagenous subunit. Sequence comparison and phylogenetic studies showed that the homologues were more related with MBL than any other collectins, and that two previously characterized trout proteins, designated MBL1 and MBL2, should...

  13. Effect of lectin from Chelidonium majus L. on normal and cancer cells in culture.

    Science.gov (United States)

    Fik, E; Wołuń-Cholewa, M; Kistowska, M; Warchoł, J B; Goździcka-Józefiak, A

    2001-01-01

    Lectin from Chelidonium majus L. (CML) significantly stimulates the proliferation of human lymphocytes and has hemagglutination activity towards group B human erythrocytes and potent antimicrobial properties against multiresistant enterococci and staphylococci. In the present work we describe the effect of lectin from Chelidonium majus L on normal and cancercells in culture in vitro. The studies were performed on three types of cells: CHO, R2C and on normal mouse fibroblasts. Effects on the cultures were examined 24 h after addition of CML. Exposure to CML resulted in growth inhibition of CHO and R2C cells but not of fibroblasts. Moreover, evident apoptotic lesions were observed in CHO cells and less well marked apoptotic lesions in R2C cells. In contrast, only insignificant numbers of fibroblasts reacted to the applied lectin.

  14. Lectins Labelled with Digoxin as a Novel Tool to Study Glycoconjugates

    Directory of Open Access Journals (Sweden)

    Jerka Dumić

    2002-01-01

    Full Text Available In recent years it has become clear that carbohydrate portions of glycoconjugates are performing numerous vital physiological functions in higher organisms. However, since glycobiology is a relatively new science, and carbohydrate structures are highly complex, the continuous development of novel analytical techniques is necessary to support the process of understanding the intricate nature of glycoconjugate structure and function. The introduction of digoxin as a novel tag for labelling of lectins that are being used to analyse glycoconjugates in immunoassay-like techniques is described. Lectins labelled with digoxin have significant advantages over biotin- or digoxigenin-labelled lectins and will hopefully prove to be a useful addition to the repertoire of glycobiological tools.

  15. Modulation of ovomucoid-specific oral tolerance in mice fed plant extracts containing lectins

    DEFF Research Database (Denmark)

    Kjær, Tanja; Frøkiær, Hanne

    2002-01-01

    We investigated the effect of feeding extracts of four different legumes (red kidney bean (Phaseolus vulgaris), peanut (Arachis hypogaea), soyabean (Glycine max) and pea (Pisum sativum) on the specific immune response against a food protein. Mice were fed ovomucoid and the specific immune response...... was evaluated. Ovomucoid fed alone resulted in oral tolerance induction measured as both a reduced ovomucoid-pecific spleen cell proliferation and antibody response. Feeding kidney-bean extract prevented induction of oral tolerance to ovomucoid measured as spleen cell proliferation in vitro. Pure kidney......-bean lectin also prevented oral tolerance induction, suggesting that lectin in the kidney-bean extract caused inhibition of oral tolerance. Parenteral administration (intravenous and intraperitoneal) of pure kidney-bean lectin had no significant influence on oral tolerance induction. Soyabean extract also...

  16. Hydrophobic spacers enhance the helicity and lectin binding of synthetic, pH-responsive glycopolypeptides.

    Science.gov (United States)

    Mildner, Robert; Menzel, Henning

    2014-12-08

    The influence of different hydrophobic spacers on the structural and lectin binding properties of well-defined glycopolypeptides decorated with galactose moieties was investigated. All glycopolypeptides were prepared from a poly(α,l-glutamic acid) (PGA) precursor via a polymer-analogous aqueous amide coupling reaction. Thereby, two alkyl spacers of different length (C6 and C11) as well as an aromatic spacer were introduced between the backbone and the galactose moieties, as confirmed by (1)H NMR spectroscopy. The secondary structure was investigated as a function of the sugar density and the pH by circular dichroism (CD) spectroscopy. It was found that the helicity in acidic medium and thus the typical coil-to-helix transition is strongly enhanced by the hydrophobic spacers. Preliminary lectin binding tests via turbidimetric assay revealed that the spacers also significantly enhance the interaction of the glycopolypeptides with the lectin RCA120.

  17. Evidence of gene conversion in genes encoding the Gal/GalNac lectin complex of Entamoeba.

    Directory of Open Access Journals (Sweden)

    Gareth D Weedall

    2011-06-01

    Full Text Available The human gut parasite Entamoeba histolytica, uses a lectin complex on its cell surface to bind to mucin and to ligands on the intestinal epithelia. Binding to mucin is necessary for colonisation and binding to intestinal epithelia for invasion, therefore blocking this binding may protect against amoebiasis. Acquired protective immunity raised against the lectin complex should create a selection pressure to change the amino acid sequence of lectin genes in order to avoid future detection. We present evidence that gene conversion has occurred in lineages leading to E. histolytica strain HM1:IMSS and E. dispar strain SAW760. This evolutionary mechanism generates diversity and could contribute to immune evasion by the parasites.

  18. The lectin-gold technique: an overview of applications to pathological problems.

    Science.gov (United States)

    Versura, P; Maltarello, M C; Bonvicini, F; Laschi, R

    1989-06-01

    Lectins are proteins, mainly of vegetal origin, which recognize glycosidic residues with high specificity; for this property they have been used for many studies of molecular biology. The colloidal gold represents at present the most popular electron dense marker employed in immunocytochemistry, since it offers intrinsic and unique characteristics which are superior to those displayed by the other markers. The cytochemical method which utilizes the gold-labelled lectins takes advantages from both the two systems, in order to optimize the localization of the glycoconjugates. The present paper reviews both the technical aspects of the preparation of the lectin-gold complex and its application to some selected pathological problems. In particular, the papers concerning the eye and ear tissues, the urinary, reproductive, nervous and digestive systems and the blood cells are quoted.

  19. The typing of Staphylococcus epidermidis by a lectin-binding assay

    DEFF Research Database (Denmark)

    Jarløv, J O; Hansen, J E; Rosdahl, V T

    1992-01-01

    A new typing method for Staphylococcus epidermidis was developed. Four biotinylated lectins--wheat germ agglutinin (WGA), soy bean agglutinin (SBA), lentil agglutinin (LCA) and Concanavalin A (ConA)--were added to immobilised whole cells of coagulase-negative staphylococci (CNS) in microtitration...... plates. The amount of bound lectin was measured by peroxidase-conjugated avidin followed by a peroxidase reaction. The method was compared to antibiotic-resistance analysis, phage typing, plasmid DNA profiles and slime production. A total of 113 isolates of CNS from 21 patients was investigated and 71...... strains of CNS, including 64 strains of S. epidermidis, were detected if all typing methods were taken into consideration. If only one typing method was used the highest discriminatory power among the S. epidermidis isolates was obtained with the lectin-binding assay which allowed 49 different strains...

  20. Isolation of Cyclospora oocysts from fruits and vegetables using lectin-coated paramagnetic beads.

    Science.gov (United States)

    Robertson, L J; Gjerde, B; Campbell, A T

    2000-10-01

    Published techniques for recovering parasites from fruit and vegetables are generally inadequate, with low and variable recovery efficiencies. Herein, we describe an improved method for analyzing fruit and vegetables for Cyclospora oocysts. The technique includes washing procedures, sonication, and separation using lectin-coated paramagnetic beads. Identification is by microscopy (differential interference contrast and fluorescence). Oocyst recovery efficiencies from mushrooms, lettuce, and raspberries were approximately 12%. Recovery efficiencies from bean sprouts were approximately 4%. Although no significant difference in recovery efficiency could be detected between samples processed using the lectin-coated beads and samples processed without this procedure, distinct advantages were apparent when the lectin-coated beads were used. A considerably smaller, cleaner final volume remained for microscopy, which increases the sensitivity of the technique and reduces operator time.

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

    Science.gov (United States)

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

    2013-07-01

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

  2. Entomotoxic properties of Dioclea violacea lectin and its effects on digestive enzymes of Anagasta kuehniella (Lepidoptera).

    Science.gov (United States)

    Oliveira, Carolina Turatti; Kunz, Daniele; Silva, Carlos Peres; Macedo, Maria Lígia Rodrigues

    2015-10-01

    Entomotoxic plant lectins have been extensively studied in the past two decades, yet the exact mechanisms underlying their toxic effects remain unknown. This study investigated the effects of Dioclea violacea lectin (DVL) on larval development in Anagasta kuehniella. Chronic exposure of larvae (from neonates to the fourth instar) demonstrated that DVL interfered with larval growth, retarding development and decreasing larval mass without affecting survival. DVL decreased trypsin-like, chymotrypsin-like, and α-amylase activities and proved resistant to proteolysis by midgut proteases up to 24h. Shorter exposures to dietary DVL had no effect on midgut enzyme activity. Feeding fourth-instar larvae with fluorescently-labeled DVL revealed lectin binding to the peritrophic membrane. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Cross-linked leucaena seed gum matrix: an affinity chromatography tool for galactose-specific lectins.

    Science.gov (United States)

    Seshagirirao, Kottapalli; Leelavathi, Chaganti; Sasidhar, Vemula

    2005-05-31

    A cross-linked leucaena (Leucaena leucocephala) seed gum (CLLSG) matrix was prepared for the isolation of galactose-specific lectins by affinity chromatography. The matrix was evaluated for affinity with a known galactose-specific lectin from the seeds of snake gourd (Trichosanthes anguina). The matrix preparation was simple and inexpensive when compared to commercial galactose-specific matrices (i.e. about 1.5 US dollars/100 ml of matrix). The current method is also useful for the demonstration of the affinity chromatography technique in laboratories. Since leucaena seeds are abundant and inexpensive, and the matrix preparation is easy, CLLSG appears to be a promising tool for the separation of galactose-specific lectins.

  4. Boronic acid functionalized peptidyl synthetic lectins: Combinatorial library design, peptide sequencing, and selective glycoprotein recognition

    Science.gov (United States)

    Bicker, Kevin L.; Sun, Jing; Lavigne, John J.; Thompson, Paul R.

    2011-01-01

    Aberrant glycosylation of cell membrane and secreted glycoproteins is a hallmark of various disease states, including cancer. The natural lectins currently used in the recognition of these glycoproteins are costly, difficult to produce, and unstable towards rigorous use. Herein we describe the design and synthesis of several boronic acid functionalized peptide-based synthetic lectin (SL) libraries, as well as the optimized methodology for obtaining peptide sequences of these SLs. SL libraries were subsequently used to identify SLs with as high as 5-fold selectivity for various glycoproteins. SLs will inevitably find a role in cancer diagnositics, given that they do not suffer from the drawbacks of natural lectins and that the combinatorial nature of these libraries allows for the identification of an SL for nearly any glycosylated biomolecule. PMID:21405093

  5. Evidence of gene conversion in genes encoding the Gal/GalNac lectin complex of Entamoeba.

    Directory of Open Access Journals (Sweden)

    Gareth D Weedall

    2011-06-01

    Full Text Available The human gut parasite Entamoeba histolytica, uses a lectin complex on its cell surface to bind to mucin and to ligands on the intestinal epithelia. Binding to mucin is necessary for colonisation and binding to intestinal epithelia for invasion, therefore blocking this binding may protect against amoebiasis. Acquired protective immunity raised against the lectin complex should create a selection pressure to change the amino acid sequence of lectin genes in order to avoid future detection. We present evidence that gene conversion has occurred in lineages leading to E. histolytica strain HM1:IMSS and E. dispar strain SAW760. This evolutionary mechanism generates diversity and could contribute to immune evasion by the parasites.

  6. [Effect of lectins from Azospirillum brasilense to peroxidase and oxalate oxidase activity regulation in wheat roots].

    Science.gov (United States)

    Alen'kina, S A; Nikitina, V E

    2010-01-01

    Lectins were extracted from the surface of nitrogen-fixing soil bacteria Azospirillum brasilense Sp7 and from its mutant A. brasilense Sp7.2.3 defective in lectin activity. The ability oflectins to stimulate the rapid formation of hydrogen peroxide related to increase of oxalate oxidase and peroxidase activity in the roots of wheat seedlings has been demonstrated. The most rapid induced pathway of hydrogen peroxide formation in the roots of wheat seedlings was the oxalic acid oxidation by oxalate oxidase which is the effect oflectin in under 10 min in a concentration of 10 microg/ml. The obtained results show that lectins from Azospirillum are capable of inducing the adaptation processes in the roots of wheat seedlings.

  7. A structural basis for the difference in specificity between the two jacalin-related lectins from mulberry (Morus nigra) bark.

    Science.gov (United States)

    Rougé, Pierre; Peumans, Willy J; Barre, Annick; Van Damme, Els J M

    2003-04-25

    The activity and specificity of a galactose-specific and a mannose-specific jacalin-related lectin from the bark of the black mulberry (Morus nigra) tree has been re-investigated using different experimental approaches. Both lectins definitely behave as polyspecific lectins recognizing galactose, mannose, and glucose even though MornigaG and MornigaM interact preferentially with galactose and mannose, respectively. The exceptionally extended size of the carbohydrate-binding site of both lectins apparently accounts for their polyspecific character. Parallel studies with other mannose-specific jacalin-related lectins confirmed that their exclusive specificity towards mannose/glucose relies on a reduced size of their carbohydrate-binding site.

  8. Lectin histochemistry of intestinal carbohydrate determinants in representatives of different classes of vertebrates

    Directory of Open Access Journals (Sweden)

    Antonyuk R.V.

    2015-12-01

    Full Text Available Background. Glycoproteins (including mucin of vertebrate’s intestine play an important role in its protection against chemical and mechanical damage and bacterial attacks. Their diversity was described by many authors, but understanding of their chemical structure remains far from complete. These data can be extended by methods of lectin histochemistry. Objective. To investigate the rearrangement of intestinal carbohydrate determinants in the context of vertebrate evolution. Methods. Distal and proximal segments of small and large intestines of humans (Homo sapiens, laboratory (Wistar rat (Rattus norvegicus f. Domesticus, rock pigeon (Columba livia, smooth snake (Coronella austriaca, common frog (Rana temporaria, common carp (Cyprinus carpio that belong to different classes of vertebrates were taken for the experiment. Nine lectins with different carbohydrate specificities: wheat germ (WGA, potato (STA, elderberry bark (SNA, golden rain bark (LABA, locust bark (RPBA, roe carp (CCRA, Phaseolus vulgaris erytroagglutinin (PHA-E, peanut (PNA and jack fruit (AIA – were included into the panel. Results. Differences in lectin staining between small and large intestine were more pronounced in higher (human, rat than in lower (frog, carp vertebrates. Lectin receptors were more diverse in frog intestine in comparison with carp. Lectin interaction with mucin secretory granules of smooth snake revealed lack of N-acetyl-D-glucosamine residues and abundance of N-acetyl-D-galactosamine determinants. Conclusion. Intestines of all studied vertebrate species demonstrate high content of secretory mucins that exposed terminal acidic carbohydrates including sialic acid. The diversity and differences in the structure of glycans of the digestive tract of vertebrates is apparently determined by several factors – diet, environmental and living conditions, intestinal microbiota interactions etc. Citation: Antonyuk RV, Lutsyk AD. [Lectin histochemistry of intestinal

  9. 植物凝集素的功能%Plant lectins: multifunctions and applications

    Institute of Scientific and Technical Information of China (English)

    鲍锦库

    2011-01-01

    Plant lectins are carbohydrate-binding proteins with nonimmune origin, and they could bind carbohydrates reversibly, agglutinate cells or precipitate polysaccharides and glycoconjugates. Due to the specific binding activities towards polysaccharides and glycoconjugates of plant lectins, they play important roles in signaling pathways, immunoregulation and plant defence. In addition, plant lectins also possess hemagglutinating and carbohydrate-binding activities as well as the anti-viral and apoptosis-inducing properties. Therefore, plant lectins have been drawn a rising attention for researchers in bioscience, medicine and agriculture. In this review, we summarize the history and multifunctions of plant lectins, and also present the applications of plant lectins.%植物凝集素是来源于植物的一类能凝集细胞和沉淀单糖或多糖复合物的非免疫来源的非酶蛋白质.由于其对于单糖或糖复合物特异性结合的能力,使得其在如信号转导、免疫反应、植物防御等诸多信号过程中均具有重要作用.同时植物凝集素具有细胞凝集、抗病毒、抗真菌及诱导细胞凋亡或自噬等多种能力,因此在生命科学、医学及农业方面均有较好的研究价值和应用前景.综述了植物凝集素的研究历史和凝集素的主要功能,并对现阶段凝集素的重点应用做简要介绍.

  10. A novel core fucose-specific lectin from the mushroom Pholiota squarrosa.

    Science.gov (United States)

    Kobayashi, Yuka; Tateno, Hiroaki; Dohra, Hideo; Moriwaki, Kenta; Miyoshi, Eiji; Hirabayashi, Jun; Kawagishi, Hirokazu

    2012-10-05

    Fucα1-6 oligosaccharide has a variety of biological functions and serves as a biomarker for hepatocellular carcinoma because of the elevated presence of fucosylated α-fetoprotein (AFP) in this type of cancer. In this study we purified a novel Fucα1-6-specific lectin from the mushroom Pholiota squarrosa by ion-exchange chromatography and affinity chromatography on thyroglobulin-agarose. The purified lectin was designated as PhoSL (P. squarrosa lectin). SDS-PAGE, MALDI-TOF mass spectrometry, and N-terminal amino acid sequencing indicate that PhoSL has a molecular mass of 4.5 kDa and consists of 40 amino acids (NH(2)-APVPVTKLVCDGDTYKCTAYLDFGDGRWVAQWDTNVFHTG-OH). Isoelectric focusing of the lectin showed bands near pI 4.0. The lectin activity was stable between pH 2.0 and 11.0 and at temperatures ranging from 0 to 100 °C for incubation times of 30 min. When PhoSL was investigated with frontal affinity chromatography using 132 pyridylaminated oligosaccharides, it was found that the lectin binds only to core α1-6-fucosylated N-glycans and not to other types of fucosylated oligosaccharides, such as α1-2-, α1-3-, and α1-4-fucosylated glycans. Furthermore, PhoSL bound to α1-6-fucosylated AFP but not to non-fucosylated AFP. In addition, PhoSL was able to demonstrate the differential expression of α1-6 fucosylation between primary and metastatic colon cancer tissues. Thus, PhoSL will be a promising tool for analyzing the biological functions of α1-6 fucosylation and evaluating Fucα1-6 oligosaccharides as cancer biomarkers.

  11. The structure of a tunicate C-type lectin from Polyandrocarpa misakiensis complexed with D -galactose.

    Science.gov (United States)

    Poget, S F; Legge, G B; Proctor, M R; Butler, P J; Bycroft, M; Williams, R L

    1999-07-23

    C-type lectins are calcium-dependent carbohydrate-recognising proteins. Isothermal titration calorimetry of the C-type Polyandrocarpa lectin (TC14) from the tunicate Polyandrocarpa misakiensis revealed the presence of a single calcium atom per monomer with a dissociation constant of 2.6 microM, and confirmed the specificity of TC14 for D -galactose and related monosaccharides. We have determined the 2.2 A X-ray crystal structure of Polyandrocarpa lectin complexed with D -galactose. Analytical ultracentrifugation revealed that TC14 behaves as a dimer in solution. This is reflected by the presence of two molecules in the asymmetric unit with the dimeric interface formed by antiparallel pairing of the two N-terminal beta-strands and hydrophobic interactions. TC14 adopts a typical C-type lectin fold with differences in structure from other C-type lectins mainly in the diverse loop regions and in the second alpha-helix, which is involved in the formation of the dimeric interface. The D -galactose is bound through coordination of the 3 and 4-hydroxyl oxygen atoms with a bound calcium atom. Additional hydrogen bonds are formed directly between serine, aspartate and glutamate side-chains of the protein and the sugar 3 and 4-hydroxyl groups. Comparison of the galactose binding by TC14 with the mannose binding by rat mannose-binding protein reveals how monosaccharide specificity is achieved in this lectin. A tryptophan side-chain close to the binding site and the distribution of hydrogen-bond acceptors and donors around the 3 and 4-hydroxyl groups of the sugar are essential determinants of specificity. These elements are, however, arranged in a very different way than in an engineered galactose-specific mutant of MBPA. Possible biological functions can more easily be understood from the fact that TC14 is a dimer under physiological conditions. Copyright 1999 Academic Press.

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

    Science.gov (United States)

    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.

  13. Structural and histological characterization of oviductal magnum and lectin-binding patterns in Gallus domesticus

    Directory of Open Access Journals (Sweden)

    Song Gwonhwa

    2011-05-01

    Full Text Available Abstract Background Although chicken oviduct is a useful model and target tissue for reproductive biology and transgenesis, little is known because of the highly specific hormonal regulation and the lack of fundamental researches, including lectin-binding activities and glycobiology. Because lectin is attached to secreted glycoproteins, we hypothesized that lectin could be bound to secretory egg-white proteins, and played a crucial role in the generation of egg-white protein in the oviduct. Hence, the purpose of this study was to investigate the structural, histological and lectin-binding characteristics of the chicken oviductal magnum from juvenile and adult hens. Methods The oviductal magnums from juvenile and adult hens were prepared for ultrastructural analysis, qRT-PCR and immunostaining. Immunohistochemistry of anti-ovalbumin, anti-ESR1 and anti-PGR, and mRNA expression of egg-white genes and steroid hormone receptor genes were evaluated. Lectin histochemical staining was also conducted in juvenile and adult oviductal magnum tissues. Results The ultrastructural analysis showed that ciliated cells were rarely developed on luminal surface in juvenile magnum, but not tubular gland cells. In adult magnum, two types of epithelium and three types of tubular gland cells were observed. qRT-PCR analysis showed that egg-white genes were highly expressed in adult oviduct compared with the juvenile. However, mRNA expressions of ESR1 and PGR were considerably higher in juvenile oviduct than adult (P Conclusions The observation of ultrastructural analysis, mRNA expression, immunohistochemistry and lectin staining showed structural and physiological characterization of juvenile and adult oviductal magnum. Consequently, oviduct study could be helped to in vitro culture of chicken oviductal cells, to develop epithelial or tubular gland cell-specific markers, and to understand female reproductive biology and endocrinology.

  14. Cellular heterogeneity in the membrana granulosa of developing rat follicles: assessment by flow cytometry and lectin binding.

    Science.gov (United States)

    Kerketze, K; Blaschuk, O W; Farookhi, R

    1996-07-01

    The hormone-mediated maturation of ovarian follicles is apparently accompanied by position-specific differentiation of cells of the membrana granulosa. We have assessed the extent of this cellular heterogeneity by flow cytometry using a variety of fluorescein isothiocyanate-labeled lectins as probes. Follicular development was stimulated in immature rats by treatment with either diethylstilbestrol (DES) or equine CG (eCG). Lectin binding to monodispersed rat granulosa cells was then analyzed by flow cytometry. Our results demonstrate that there are two distinct populations of small (4-7 microM) and large (9-12 microM) granulosa cells in follicles from DES- and eCG-treated animals. Both populations appear to be mitotically active and show specific lectin-binding characteristics. Six lectins (canavalia ensiforms, triticum vulgaris, maclura pomifera, erythrina cristagalli, jacalin, and vicia villosa) bind equally to both small and large granulosa cells from the DES- and eCG-treated rats. In contrast, no binding to either cell population was detected with six other lectins (dolichos biflorus, griffonia simplicifolia-II, lycopersicon esculentum, datura stramonium, solanum tuberosum, and ulex europaeus). Furthermore, four galactose-binding lectins (bauhinia purpurea, glysine maximus, griffonia simplicifolia-I, and arachis hypogaea) were found to identify specific subsets of granulosa cells. Three of these lectins (bauhinia purpurea, glysine maximus, and griffonia simplicifolia-I) bind to only small granulosa cells from either DES- or eCG- treated immature rats. The fourth lectin (arachis hypogaea) identifies subpopulations of both small and large granulosa cells. Application of the four galactose-specific lectins to fixed sections of frozen ovaries demonstrated binding to the perioocyte and cumulus granulosa cells. We conclude that cellular heterogeneity exists within the follicular epithelium at various stages-specific lectin-binding sites.

  15. Expression conservation within the circadian clock of a monocot: natural variation at barley Ppd-H1 affects circadian expression of flowering time genes, but not clock orthologs

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    Campoli Chiara

    2012-06-01

    Full Text Available Abstract Background The circadian clock is an endogenous mechanism that coordinates biological processes with daily changes in the environment. In plants, circadian rhythms contribute to both agricultural productivity and evolutionary fitness. In barley, the photoperiod response regulator and flowering-time gene Ppd-H1 is orthologous to the Arabidopsis core-clock gene PRR7. However, relatively little is known about the role of Ppd-H1 and other components of the circadian clock in temperate crop species. In this study, we identified barley clock orthologs and tested the effects of natural genetic variation at Ppd-H1 on diurnal and circadian expression of clock and output genes from the photoperiod-response pathway. Results Barley clock orthologs HvCCA1, HvGI, HvPRR1, HvPRR37 (Ppd-H1, HvPRR73, HvPRR59 and HvPRR95 showed a high level of sequence similarity and conservation of diurnal and circadian expression patterns, when compared to Arabidopsis. The natural mutation at Ppd-H1 did not affect diurnal or circadian cycling of barley clock genes. However, the Ppd-H1 mutant was found to be arrhythmic under free-running conditions for the photoperiod-response genes HvCO1, HvCO2, and the MADS-box transcription factor and vernalization responsive gene Vrn-H1. Conclusion We suggest that the described eudicot clock is largely conserved in the monocot barley. However, genetic differentiation within gene families and differences in the function of Ppd-H1 suggest evolutionary modification in the angiosperm clock. Our data indicates that natural variation at Ppd-H1 does not affect the expression level of clock genes, but controls photoperiodic output genes. Circadian control of Vrn-H1 in barley suggests that this vernalization responsive gene is also controlled by the photoperiod-response pathway. Structural and functional characterization of the barley circadian clock will set the basis for future studies of the adaptive significance of the circadian clock in

  16. Expression conservation within the circadian clock of a monocot: natural variation at barley Ppd-H1 affects circadian expression of flowering time genes, but not clock orthologs.

    Science.gov (United States)

    Campoli, Chiara; Shtaya, Munqez; Davis, Seth J; von Korff, Maria

    2012-06-21

    The circadian clock is an endogenous mechanism that coordinates biological processes with daily changes in the environment. In plants, circadian rhythms contribute to both agricultural productivity and evolutionary fitness. In barley, the photoperiod response regulator and flowering-time gene Ppd-H1 is orthologous to the Arabidopsis core-clock gene PRR7. However, relatively little is known about the role of Ppd-H1 and other components of the circadian clock in temperate crop species. In this study, we identified barley clock orthologs and tested the effects of natural genetic variation at Ppd-H1 on diurnal and circadian expression of clock and output genes from the photoperiod-response pathway. Barley clock orthologs HvCCA1, HvGI, HvPRR1, HvPRR37 (Ppd-H1), HvPRR73, HvPRR59 and HvPRR95 showed a high level of sequence similarity and conservation of diurnal and circadian expression patterns, when compared to Arabidopsis. The natural mutation at Ppd-H1 did not affect diurnal or circadian cycling of barley clock genes. However, the Ppd-H1 mutant was found to be arrhythmic under free-running conditions for the photoperiod-response genes HvCO1, HvCO2, and the MADS-box transcription factor and vernalization responsive gene Vrn-H1. We suggest that the described eudicot clock is largely conserved in the monocot barley. However, genetic differentiation within gene families and differences in the function of Ppd-H1 suggest evolutionary modification in the angiosperm clock. Our data indicates that natural variation at Ppd-H1 does not affect the expression level of clock genes, but controls photoperiodic output genes. Circadian control of Vrn-H1 in barley suggests that this vernalization responsive gene is also controlled by the photoperiod-response pathway. Structural and functional characterization of the barley circadian clock will set the basis for future studies of the adaptive significance of the circadian clock in Triticeae species.

  17. Structural and histological characterization of oviductal magnum and lectin-binding patterns in Gallus domesticus.

    Science.gov (United States)

    Jung, Jin Gyoung; Lim, Whasun; Park, Tae Sub; Kim, Jin Nam; Han, Beom Ku; Song, Gwonhwa; Han, Jae Yong

    2011-05-08

    Although chicken oviduct is a useful model and target tissue for reproductive biology and transgenesis, little is known because of the highly specific hormonal regulation and the lack of fundamental researches, including lectin-binding activities and glycobiology. Because lectin is attached to secreted glycoproteins, we hypothesized that lectin could be bound to secretory egg-white proteins, and played a crucial role in the generation of egg-white protein in the oviduct. Hence, the purpose of this study was to investigate the structural, histological and lectin-binding characteristics of the chicken oviductal magnum from juvenile and adult hens. The oviductal magnums from juvenile and adult hens were prepared for ultrastructural analysis, qRT-PCR and immunostaining. Immunohistochemistry of anti-ovalbumin, anti-ESR1 and anti-PGR, and mRNA expression of egg-white genes and steroid hormone receptor genes were evaluated. Lectin histochemical staining was also conducted in juvenile and adult oviductal magnum tissues. The ultrastructural analysis showed that ciliated cells were rarely developed on luminal surface in juvenile magnum, but not tubular gland cells. In adult magnum, two types of epithelium and three types of tubular gland cells were observed. qRT-PCR analysis showed that egg-white genes were highly expressed in adult oviduct compared with the juvenile. However, mRNA expressions of ESR1 and PGR were considerably higher in juvenile oviduct than adult (P magnum. In contrast, PAS was positive only in adult oviductal tubular gland. Lectins were selectively bound to oviductal epithelium, stroma, and tubular gland cells. Particularly, lectin-ConA and WGA were bound to electron-dense secretory granules in tubular gland. The observation of ultrastructural analysis, mRNA expression, immunohistochemistry and lectin staining showed structural and physiological characterization of juvenile and adult oviductal magnum. Consequently, oviduct study could be helped to in vitro

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

    DEFF Research Database (Denmark)

    Nuti, M; Zizzari, I; Napoletano, C;

    2011-01-01

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

  19. Inactivation and fragmentation of lectin from Bothrops leucurus snake venom by gamma irradiation

    Science.gov (United States)

    Nunes, E. S.; Souza, M. A. A.; Vaz, A. F. M.; Coelho, L. C. B. B.; Aguiar, J. S.; Silva, T. G.; Guarnieri, M. C.; Melo, A. M. M. A.; Oliva, M. L. V.; Correia, M. T. S.

    2012-04-01

    Gamma radiation alters the molecular structure of biomolecules and is able to mitigate the action of snake venoms and their isolated toxins. The effect of γ-radiation on the folding of Bothrops lecurus venom lectin was measured by a hemagglutinating assay, intrinsic and bis-ANS fluorescence. Intrinsic and bis-ANS fluorescence analyses indicated that irradiation caused unfolding followed by aggregation of the lectin. Our results suggest that irradiation can lead to significant changes in the protein structure, which may promote the loss of its binding property and toxic action.

  20. Assessment of lectin and HILIC based enrichment protocols for characterization of serum glycoproteins by mass spectrometry

    DEFF Research Database (Denmark)

    Calvano, Cosima D; Zambonin, Carlo G; Jensen, Ole Nørregaard

    2008-01-01

    glycosylation profiles are associated with certain human ailments. Glycoprotein analysis by mass spectrometry of biological samples, such as blood serum, is hampered by sample complexity and the low concentration of the potentially informative glycopeptides and -proteins. We assessed the utility of lectin...... of 63 glycosylation sites in 38 proteins were identified by both methods, demonstrating distinct differences and complementarity. Serial application of custom-made microcolumns of mixed, immobilized lectins proved efficient for recovery and analysis of glycopeptides from serum samples of breast cancer...

  1. Crystallization and initial X-ray diffraction analysis of a mannose-binding lectin from champedak.

    Science.gov (United States)

    Gabrielsen, Mads; Abdul-Rahman, Puteri Shafinaz; Isaacs, Neil W; Hashim, Onn Haji; Cogdell, Richard J

    2010-05-01

    Mannose-binding lectin from champedak (Artocarpus integer) is a homotetramer with a single-monomer molecular weight of 16 800 Da. Previous work has shown it to bind IgE and IgM, as well as being a mitogen of T cells in humans. Champedak mannose-binding lectin has successfully been used to detect altered glycosylation states of serum proteins. The protein was crystallized at 293 K in space group P2(1)2(1)2(1) (unit-cell parameters a = 76.89, b = 86.22, c = 95.37 A) and the crystals diffracted to 2.0 A resolution.

  2. Odorranalectin is a small peptide lectin with potential for drug delivery and targeting.

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    Jianxu Li

    Full Text Available BACKGROUND: Lectins are sugar-binding proteins that specifically recognize sugar complexes. Based on the specificity of protein-sugar interactions, different lectins could be used as carrier molecules to target drugs specifically to different cells which express different glycan arrays. In spite of lectin's interesting biological potential for drug targeting and delivery, a potential disadvantage of natural lectins may be large size molecules that results in immunogenicity and toxicity. Smaller peptides which can mimic the function of lectins are promising candidates for drug targeting. PRINCIPAL FINDINGS: Small peptide with lectin-like behavior was screened from amphibian skin secretions and its structure and function were studied by NMR, NMR-titration, SPR and mutant analysis. A lectin-like peptide named odorranalectin was identified from skin secretions of Odorrana grahami. It was composed of 17 aa with a sequence of YASPKCFRYPNGVLACT. L-fucose could specifically inhibit the haemagglutination induced by odorranalectin. (125I-odorranalectin was stable in mice plasma. In experimental mouse models, odorranalectin was proved to mainly conjugate to liver, spleen and lung after i.v. administration. Odorranalectin showed extremely low toxicity and immunogenicity in mice. The small size and single disulfide bridge of odorranalectin make it easy to manipulate for developing as a drug targeting system. The cyclic peptide of odorranalectin disclosed by solution NMR study adopts a beta-turn conformation stabilized by one intramolecular disulfide bond between Cys6-Cys16 and three hydrogen bonds between Phe7-Ala15, Tyr9-Val13, Tyr9-Gly12. Residues K5, C6, F7, C16 and T17 consist of the binding site of L-fucose on odorranalectin determined by NMR titration and mutant analysis. The structure of odorranalectin in bound form is more stable than in free form. CONCLUSION: These findings identify the smallest lectin so far, and show the application potential of

  3. Inhibition of human immunodeficiency virus 1 (HIV-1) and herpes simplex virus 1 (HSV-1) infectivity with a broad range of lectins

    DEFF Research Database (Denmark)

    Hansen, J E; Nielsen, C; Vestergaard, B F

    1991-01-01

    Five lectins with specificity for N- and O-linked oligosaccharides were examined for inhibition of HIV-1 and HSV-1 infectivity in vitro. HIV-1 isolate HTLVIIIB was preincubated with lectin and subsequently inoculated onto MT-4 cells. Lectins specific for N-linked oligosaccharides blocked HIV infe......-1 infection, the most potent inhibition was found with the lectin HPA. These results indicate that lectins may have a broad antiviral effect on enveloped viruses only limited by types of oligosaccharides present on individual viruses....

  4. Mouse Ficolin B Has an Ability to Form Complexes with Mannose-Binding Lectin-Associated Serine Proteases and Activate Complement through the Lectin Pathway

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    Yuichi Endo

    2012-01-01

    Full Text Available Ficolins are thought to be pathogen-associated-molecular-pattern-(PAMP- recognition molecules that function to support innate immunity. Like mannose-binding lectins (MBLs, most mammalian ficolins form complexes with MBL-associated serine proteases (MASPs, leading to complement activation via the lectin pathway. However, the ability of murine ficolin B, a homologue of human M-ficolin, to perform this function is still controversial. The results of the present study show that ficolin B in mouse bone marrow is an oligomeric protein. Ficolin B, pulled down using GlcNAc-agarose, contained very low, but detectable, amounts of MASP-2 and small MBL-associated protein (sMAP and showed detectable C4-deposition activity on immobilized N-acetylglucosamine. These biochemical features of ficolin B were confirmed using recombinant mouse ficolin B produced in CHO cells. Taken together, these results suggest that like other mammalian homologues, murine ficolin B has an ability to exert its function via the lectin pathway.

  5. Isolation of a galactose-binding lectin from the venom of the snake Bothrops godmani (Godmann's pit viper).

    Science.gov (United States)

    Lomonte, B; Rojas, G; Gutiérrez, J M; Ramírez, G

    1990-01-01

    A galactose-binding lectin, isolated from the venom of B. godmani by affinity chromatography, is an acidic protein (pI 4.9) with a subunit mol. wt of about 14,000, occurring mostly as a disulfide-linked dimer of 28,000. A small proportion of lectin appears as a monomer and as a tetramer. The lectin agglutinates erythrocytes from mice, rabbit, cow and human (all ABO types, either Rh positive or negative), but does not agglutinate horse, sheep, goat and snake (Oxybelis aeneus, Colubridae) erythrocytes. The agglutinating activity is inhibited by 1 mM EDTA. The lectin is devoid of lethal, hemorrhagic, myotoxic, proteolytic and phospholipase A2 activities. It is not mitogenic for human peripheral blood mononuclear cells. The only effect observed was a moderate induction of edema in the footpad of mice, with a minimal edema-forming dose of 22 micrograms. This effect developed rapidly, and was significantly inhibited by i.p. administration of cyproheptadine, a histamine and serotonin antagonist, before injection of the lectin. Despite the edema-forming activity observed, the low concentration of lectin in crude venom, together with its relatively low potency, suggest that this lectin is not a key component in the development of edema following envenomations by B. godmani.

  6. A Galactose-Binding Lectin Isolated from Aplysia kurodai (Sea Hare Eggs Inhibits Streptolysin-Induced Hemolysis

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    Imtiaj Hasan

    2014-09-01

    Full Text Available A specific galactose-binding lectin was shown to inhibit the hemolytic effect of streptolysin O (SLO, an exotoxin produced by Streptococcus pyogenes. Commercially available lectins that recognize N-acetyllactosamine (ECA, T-antigen (PNA, and Tn-antigen (ABA agglutinated rabbit erythrocytes, but had no effect on SLO-induced hemolysis. In contrast, SLO-induced hemolysis was inhibited by AKL, a lectin purified from sea hare (Aplysia kurodai eggs that recognizes α-galactoside oligosaccharides. This inhibitory effect was blocked by the co-presence of d-galactose, which binds to AKL. A possible explanation for these findings is that cholesterol-enriched microdomains containing glycosphingolipids in the erythrocyte membrane become occupied by tightly stacked lectin molecules, blocking the interaction between cholesterol and SLO that would otherwise result in penetration of the membrane. Growth of S. pyogenes was inhibited by lectins from a marine invertebrate (AKL and a mushroom (ABA, but was promoted by a plant lectin (ECA. Both these inhibitory and promoting effects were blocked by co-presence of galactose in the culture medium. Our findings demonstrate the importance of glycans and lectins in regulating mechanisms of toxicity, creation of pores in the target cell membrane, and bacterial growth.

  7. Use of Aleuria alantia Lectin Affinity Chromatography to Enrich Candidate Biomarkers from the Urine of Patients with Bladder Cancer

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    Sarah R. Ambrose

    2015-09-01

    Full Text Available Developing a urine test to detect bladder tumours with high sensitivity and specificity is a key goal in bladder cancer research. We hypothesised that bladder cancer-specific glycoproteins might fulfill this role. Lectin-ELISAs were used to study the binding of 25 lectins to 10 bladder cell lines and serum and urine from bladder cancer patients and non-cancer controls. Selected lectins were then used to enrich glycoproteins from the urine of bladder cancer patients and control subjects for analysis by shotgun proteomics. None of the lectins showed a strong preference for bladder cancer cell lines over normal urothlelial cell lines or for urinary glycans from bladder cancer patients over those from non-cancer controls. However, several lectins showed a strong preference for bladder cell line glycans over serum glycans and are potentially useful for enriching glycoproteins originating from the urothelium in urine. Aleuria alantia lectin affinity chromatography and shotgun proteomics identified mucin-1 and golgi apparatus protein 1 as proteins warranting further investigation as urinary biomarkers for low-grade bladder cancer. Glycosylation changes in bladder cancer are not reliably detected by measuring lectin binding to unfractionated proteomes, but it is possible that more specific reagents and/or a focus on individual proteins may produce clinically useful biomarkers.

  8. Cytotoxic and Antiproliferative Effect of Tepary Bean Lectins on C33-A, MCF-7, SKNSH, and SW480 Cell Lines

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    Carmen Valadez-Vega

    2014-07-01

    Full Text Available For many years, several studies have been employing lectin from vegetables in order to prove its toxic effect on various cell lines. In this work, we analyzed the cytotoxic, antiproliferative, and post-incubatory effect of pure tepary bean lectins on four lines of malignant cells: C33-A; MCF-7; SKNSH, and SW480. The tests were carried out employing MTT and 3[H]-thymidine assays. The results showed that after 24 h of lectin exposure, the cells lines showed a dose-dependent cytotoxic effect, the effect being higher on MCF-7, while C33-A showed the highest resistance. Cell proliferation studies showed that the toxic effect induced by lectins is higher even when lectins are removed, and in fact, the inhibition of proliferation continues after 48 h. Due to the use of two techniques to analyze the cytotoxic and antiproliferative effect, differences were observed in the results, which can be explained by the fact that one technique is based on metabolic reactions, while the other is based on the 3[H]-thymidine incorporated in DNA by cells under division. These results allow concluding that lectins exert a cytotoxic effect after 24 h of exposure, exhibiting a dose-dependent effect. In some cases, the cytotoxic effect is higher even when the lectins are eliminated, however, in other cases, the cells showed a proliferative effect.

  9. Red kidney bean (Phaseolus vulgaris lectin stimulation increases the number of enterochromaffin cells in the small intestine of suckling piglets

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    Zacharko-Siembida Anna

    2014-06-01

    Full Text Available The quantities and distribution patterns of serotonin-immunoreactive (serotonin-IR enterochromaffin cells (EC were studied immunohistochemically in the small intestine of suckling piglets stimulated with red kidney bean lectin, and in nonstimulated, control animals. The co-expression patterns of serotonin with somatostatin (SOM or corticotropin releasing-factor (CRF were also studied. After the lectin treatment, the increased numbers of EC were noted in the duodenum of experimental animals. Lectin stimulation did not change the proportions of EC in the jejunum and ileum. In the duodenal epithelium of the lectin-stimulated piglets, the vast majority of serotonin-IR EC were distributed at the basis of crypts. After the lectin administration, the proportions of serotonin-IR/SOM-IR EC were statistically similar in all sections of the small intestine. No upregulation of CRF was found in duodenal, jejunal, and ileal EC of lectin-treated animals. The findings demonstrated that red kidney bean lectin increased the serotonin reservoir in the duodenum, and thus may be an effective stimulant of the gut maturation in suckling mammals.

  10. Mannan-binding lectin in cerebrospinal fluid: a leptomeningeal protein

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    Reiber Hansotto

    2012-08-01

    Full Text Available Abstract Background Mannan-binding lectin (MBL, a protein of the innate immune response is attracting increasing clinical interest, in particularly in relation to its deficiency. Due to its involvement in brain diseases, identifying the source of MBL in CSF is important. Analysis of cerebrospinal fluid (CSF can provide data that discriminates between blood-, brain-, and leptomeninges-derived proteins. To detect the source of MBL in CSF we need to consider three variables: the molecular size-dependent concentration gradient between CSF and blood, the variation in transfer between blood and CSF, and the CSF MBL concentration correlation with the albumin CSF/serum quotient (QAlb, i.e., with CSF flow rate. Methods MBL was assayed in samples of CSF and serum with an ELISA, coated with anti MBL antibodies. Routine parameters such as albumin-, immunoglobulin- CSF/serum quotients, oligoclonal IgG and cell count were used to characterize the patient groups. Groups comprised firstly, control patients without organic brain disease with normal CSF and normal barrier function and secondly, patients without inflammatory diseases but with increased QAlb, i.e. with a blood CSF barrier dysfunction. Results MBL concentration in CSF was at least five-fold higher than expected for a molecular-size-dependent passage from blood. Secondly, in a QIgM/QAlb quotient diagram (Reibergram 9/13 cases showed an intrathecal fraction in some cases over 80% of total CSF MBL concentration 3 The smaller inter-individual variation of MBL concentrations in CSF of the control group (CV = 66% compared to the MBL concentrations in serum (CV = 146% indicate an independent source of MBL in CSF. 4 The absolute MBL concentration in CSF increases with increasing QAlb. Among brain-derived proteins in CSF only the leptomeningeal proteins showed a (linear increase with decreasing CSF flow rate, neuronal and glial proteins are invariant to changes of QAlb. Conclusions MBL in CSF is

  11. Lectin-carbohydrate interactions on nanoporous gold monoliths.

    Science.gov (United States)

    Tan, Yih Horng; Fujikawa, Kohki; Pornsuriyasak, Papapida; Alla, Allan J; Ganesh, N Vijaya; Demchenko, Alexei V; Stine, Keith J

    2013-07-01

    Monoliths of nanoporous gold (np-Au) were modified with self-assembled monolayers of octadecanethiol (C18-SH), 8-mercaptooctyl α-D-mannopyranoside (αMan-C8-SH), and 8-mercapto-3,6-dioxaoctanol (HO-PEG2-SH), and the loading was assessed using thermogravimetric analysis (TGA). Modification with mixed SAMs containing αMan-C8-SH (at a 0.20 mole fraction in the SAM forming solution) with either octanethiol or HO-PEG2-SH was also investigated. The np-Au monoliths modified with αMan-C8-SH bind the lectin Concanavalin A (Con A), and the additional mass due to bound protein was assessed using TGA analysis. A comparison of TGA traces measured before and after exposure of HO-PEG2-SH modified np-Au to Con A showed that the non-specific binding of Con A was minimal. In contrast, np-Au modified with octanethiol showed a significant mass loss due to non-specifically adsorbed Con A. A significant mass loss was also attributed to binding of Con A to bare np-Au monoliths. TGA revealed a mass loss due to the binding of Con A to np-Au monoliths modified with pure αMan-C8-SH. The use of mass losses determined by TGA to compare the binding of Con A to np-Au monoliths modified by mixed SAMs of αMan-C8-SH and either octanethiol or HO-PEG2-SH revealed that binding to mixed SAM modified surfaces is specific for the mixed SAMs with HO-PEG2-SH but shows a significant contribution from non-specific adsorption for the mixed SAMs with octanethiol. Minimal adsorption of immunoglobulin G (IgG) and peanut agglutinin (PNA) towards the mannoside modified np-Au monoliths was demonstrated. A greater mass loss was found for Con A bound onto the monolith than for either IgG or PNA, signifying that the mannose presenting SAMs in np-Au retain selectivity for Con A. TGA data also provide evidence that Con A bound to the αMan-C8-SH modified np-Au can be eluted by flowing a solution of methyl α-D-mannopyranoside through the structure. The presence of Con A proteins on the modified np-Au surface was

  12. In vitro and in vivo interaction of Entamoeba histolytica Gal/GalNAc lectin with various target cells: an immunocytochemical analysis.

    Science.gov (United States)

    Pacheco, Judith; Shibayama, Mineko; Campos, Rafael; Beck, David L; Houpt, Erick; Petri, William A; Tsutsumi, Víctor

    2004-03-01

    The Gal/GalNAc lectin of Entamoeba histolytica trophozoites plays an important role in adhesion. The distribution and final destiny of the lectin during the interaction with host cells are poorly understood. Using monoclonal and polyclonal antibodies against the lectin we studied by immunocytochemistry the in vitro and in vivo interaction of E. histolytica trophozoites with human and hamster hepatocytes. We also analyzed the presence and distribution of the lectin in a mouse model of intestinal amoebiasis. In all cases, trophozoites were highly labeled by anti-lectin antibodies. Cultured human and hamster hepatocytes in contact with, or localized at the vicinity of parasites were also labeled by anti-lectin antibodies. Most of the labeled hepatocytes showed variable degrees of cell damage. Hepatocytes distantly localized from the parasites were also stained with the anti-lectin antibodies. Immunolabeling of tissue sections from different stages of the development of experimental amoebic liver abscess in hamsters showed inflammatory foci containing lectin-labeled trophozoites, hepatocytes, and sinusoidal and inflammatory cells. Lectin-containing hepatocytes had vacuolated cytoplasm with some nuclei with a condensed appearance. Damaged intestinal epithelium also was labeled with anti-lectin antibodies in a mouse model of intestinal amoebiasis. Electron microscopy of axenically cultured trophozoites using gold-labeled monoclonal and polyclonal anti-lectin antibody showed that plasma membrane, vacuole membranes and areas of cell cytosol were labeled. Higher deposits of gold particles in plasma membrane suggestive of cell secretion were observed. Our results demonstrated that Gal/GalNAc lectin was bound and captured by different target cells, and that host cells containing the lectin showed signs of cell damage. The contribution of lectin transfer to host cells in adherence and cell injury remains to be determined.

  13. Expression of lectin-like transcript 1, the ligand for CD161, in rheumatoid arthritis

    NARCIS (Netherlands)

    Chalan, P.; Bijzet, J.; Kroesen, B.-J.; Brouwer, Liesbeth; Boots, M.

    2015-01-01

    Background: Precursor Th17 lineage cells expressing CD161 are implicated in rheumatoid arthritis pathogenesis. CD4+CD161+ T cells were found to accumulate in RA synovial fluid and tissue where they may acquire a non-classical T-helper 1 phenotype. The sole endogenous ligand for CD161 is lectin-like

  14. Influence of major surgery on the mannan-binding lectin pathway of innate immunity

    DEFF Research Database (Denmark)

    Ytting, H; Christensen, I J; Basse, L;

    2006-01-01

    The mannan-binding lectin (MBL) pathway of complement activation is important in host defence against pathogens and possibly against cancer. We investigated the effect of major surgery on two central components of the MBL pathway; MBL and the MBL-associated serine protease MASP-2, and for compari...

  15. Extrinsic functions of lectin domains in O-N-acetylgalactosamine glycan biosynthesis

    DEFF Research Database (Denmark)

    Lorenz, Virginia; Ditamo, Yanina; Cejas, Romina B;

    2016-01-01

    Glycan biosynthesis occurs mainly in Golgi. Molecular organization and functional regulation of this process are not well understood. We evaluated the extrinsic effect of lectin domains (β-trefoil fold) of polypeptide GalNAc-transferases (ppGalNAc-Ts) on catalytic activity of glycosyltransferases...

  16. Lectin-based glycoproteomics to explore and analyze hepatocellular carcinoma-related glycoprotein markers.

    Science.gov (United States)

    Dai, Zhi; Zhou, Jian; Qiu, Shuang-Jian; Liu, Yin-Kun; Fan, Jia

    2009-09-01

    More and more new diagnostic biomarkers of hepatocellular carcinoma (HCC) have been found in association with advances in the standardization of 2-DE coupled with MS analysis. However, the diagnosis of HCC is still detected in the late stages of the disease, when treatment options are limited and prognosis is poor. The glycosylation of proteins is known to change in tumor cells during the development of HCC as the result of alterations in the levels of glycosyltransferases, such as increased fucosylation of Golgi Protein 73 and alpha-fetoprotein. These structural changes can influence the function or physiochemical properties of a protein, resulting in abnormal cancer cell behavior. Therefore, identification of HCC-related glycoprotein markers and analysis of glycan structural alterations might assist in the early detection of HCC. Here, we summarize lectin-based glycoproteomic strategies for the discovery of relevant biomarkers of HCC. The carbohydrate-binding specificities of different lectins offer a biological affinity approach that complements existing MS capabilities. These strategies involve the enrichment of glycoproteins or glycopeptides by lectins, followed by releasing carbohydrates with peptide-N-glycosidase F or reductive beta-elimination. The obtained glycopeptides are then identified by automated MS/MS and structural analysis of glycans is performed through modern methods such as quadrupole IT-TOF, MALDI-TOF/TOF and lectin microarray. These strategies will lead to faster and more clinically adaptable tests with greater sensitivity and specificity.

  17. Snowdrop lectin (Galanthus nivalis agglutinin) in aphid honeydew negatively affects survival of a honeydew- consuming parasitoid

    NARCIS (Netherlands)

    Hogervorst, P.A.M.; Wäckers, F.L.; Woodring, J.; Romeis, J.

    2009-01-01

    1 Insecticidal proteins can be excreted in the honeydew when sap-sucking insects feed on insect-resistant transgenic plants. Honeydew can be an important source of carbohydrates, thus potentially exposing a broad range of honeydew-feeding insects to transgene products. 2 Snowdrop lectin (Galanthus n

  18. Binding of Galanthus nivalis lectin to Chlamydia trachomatis and inhibition of in vitro infection.

    Science.gov (United States)

    Amin, K; Beillevaire, D; Mahmoud, E; Hammar, L; Mårdh, P A; Fröman, G

    1995-10-01

    A glycoprotein present in Chlamydia trachomatis, serotype L1, elementary bodies (EBs) was earlier found to bind the lectin from Galanthus nivalis (GNA). In the present paper we investigate the interaction of GNA with chlamydial EBs and its effect on in vitro infectivity. The binding affinity was studied with 125I-GNA lectin. Within 15 min about 80% maximal binding was obtained. The chlamydia-GNA interaction was inhibited by alpha-methylmannoside, causing a decrease of about 50% at 1 mM. Curve fit analyses indicated two types of binding sites for GNA on the EBs. The affinity to these differed by a factor of 15. The influence of the lectin on the ability of C. trachomatis to infect McCoy cells was also investigated. There was a GNA-dependent inhibition with a 50% reduction in the number of intracellular inclusions at 0.2 microM of the lectin. The findings indicate the presence of terminal mannose structures on the chlamydial surface at or in the proximity of the cell-binding domains. Mannose-binding proteins of eukaryotic cells could be important for the initial uptake of EBs.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    OBJECTIVES: To assess the involvement of ficolin-3, the main initiator of the lectin complement pathway (LCP), in subarachnoid hemorrhage (SAH) pathology and outcome. METHODS: In this preliminary exploratory study, plasma concentration of ficolin-3 and of ficolin-3-mediated functional LCP activit...

  20. Intestinally secreted C-type lectin Reg3b attenuates salmonellosis but not listeriosis in mice

    NARCIS (Netherlands)

    Ampting, van M.T.J.; Loonen, L.M.P.; Schonewille, A.J.; Konings, I.; Vink, C.; Iovanna, J.; Chamaillard, M.; Dekker, J.; Meer, van der R.; Wells, J.; Bovee-Oudenhoven, I.M.J.

    2012-01-01

    The Reg3 protein family, including the human member designated pancreatitis-associated protein (PAP), consists of secreted proteins that contain a C-type lectin domain involved in carbohydrate binding. They are expressed by intestinal epithelial cells. Colonization of germ-free mice and intestinal i

  1. Transmission-blocking antibodies against mosquito C-type lectins for dengue prevention.

    Science.gov (United States)

    Liu, Yang; Zhang, Fuchun; Liu, Jianying; Xiao, Xiaoping; Zhang, Siyin; Qin, Chengfeng; Xiang, Ye; Wang, Penghua; Cheng, Gong

    2014-02-01

    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.

  2. A `Clicked' Tetrameric Hydroxamic Acid Glycopeptidomimetic Antagonizes Sugar-Lectin Interactions On The Cellular Level

    Science.gov (United States)

    Zhang, Hai-Lin; Zang, Yi; Xie, Juan; Li, Jia; Chen, Guo-Rong; He, Xiao-Peng; Tian, He

    2014-07-01

    A tetrameric N-acetyl galactosaminyl (GalNAc) peptidomimetic was constructed by N-acetylation of repeating proline-based hydroxamic acid units, followed by a convergent `click chemistry' coupling. This novel glycopeptidomimetic was determined to effectively antagonize the interaction between a transmembrane hepatic lectin and GalNAc on the cellular level.

  3. Immunogold study on lectin binding in the porcine zona pellucida and granulosa cells

    Directory of Open Access Journals (Sweden)

    F Parillo

    2009-06-01

    Full Text Available An ultrastructural localization of lectin receptors on the zona pellucida (ZP of porcine antral oocytes and on the granulosa cells was performed using a panel of horseradish peroxidase- labelled lectins in conjunction with antiperoxidase antibody and protein A-gold. In some cases, lectin incubation was preceded by sialidase digestion. WGA-, Con-A-, UEA-I-, RCA-I-, PNA- and SBA-reactive sites were distributed differently in the porcine ZP. Sialidase digestion increased the positivity obtained with RCA-I and it was necessary to promote PNA and SBA reactivity. These results indicated that the ZP contained N-acetylglucosamine, a-mannose, a- fucose, b-Gal-(1-4GlcNAc, b-Gal- (1-3GalNAc, b-GalNAc and sialic acid residues. We also observed the presence of vesicles in both the ooplasm and granulosa cells, showing a similar lectin binding pattern to that of the ZP, thus suggesting that the oocyte and granulosa cells are the site of synthesis of ZP glucidic determinants.

  4. Glycophenotype Evaluation in Cutaneous Tumors Using Lectins Labeled with Acridinium Ester

    Directory of Open Access Journals (Sweden)

    Luiza Rayanna Amorim Lima

    2013-01-01

    Full Text Available Background. Tumor cells show alterations in their glycosylation patterns when compared to normal cells. Lectins can be used to evaluate these glycocode changes. Chemiluminescence assay is an effective technique for quantitative analysis of proteins, nucleic acids, and carbohydrates due to its high sensitivity, specificity, and rapid testing. Objective. To use histochemiluminescence based on lectin conjugated to acridinium ester (AE for the investigation of glycophenotype changes in cutaneous tumors. Methods. Concanavalin A (Con A, Peanut agglutinin (PNA, Ulex europaeus agglutinin-I (UEA-I, and Maackia amurensis agglutinin (MAA were conjugated to acridinium ester. Biopsies of cutaneous tumors and normal skin were incubated with the lectins-AE, and chemiluminescence was quantified and expressed as Relative Light Units (RLU. Results. Actinic keratosis (AK, keratoacanthoma (KA, squamous cell carcinoma (SCC, and basal cell carcinoma (BCC showed lower expression of α-D-glucose/mannose and α-L-fucose residues compared to normal tissue. Cutaneous tumors displayed higher expression of Gal-β(1-3-GalNAc residues than normal tissue. AK and SCC exhibited higher expression of Neu5Ac-α(2,3Gal residues than normal epidermis. KA and BCC showed equivalent RLU values compared to normal tissue. Conclusions. Lectin histochemiluminescence allowed quantitative assessment of the carbohydrate expression in cutaneous tissues, contributing to eliminate the subjectivity of conventional techniques used in the histopathological diagnosis.

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

    Science.gov (United States)

    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.

  6. Mannose-binding lectin does not explain the course and outcome of pregnancy in rheumatoid arthritis

    NARCIS (Netherlands)

    F.E. Geijn (Fleur); Y.A. de Man (Yael); M. Wuhrer (Manfred); S.P. Willemsen (Sten); A.M. Deelder (André); J.M.W. Hazes (Mieke); R.J.E.M. Dolhain (Radboud)

    2011-01-01

    textabstractIntroduction: Rheumatoid arthritis (RA) improves during pregnancy and flares after delivery. It has been hypothesized that high levels of the complement factor mannose-binding lectin (MBL) are associated with a favourable disease course of RA by facilitating the clearance of pathogenic i

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

    Science.gov (United States)

    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.

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

    OpenAIRE

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

    2007-01-01

    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.

  9. Levels of complexity in pathogen recognition by C-type lectins.

    NARCIS (Netherlands)

    Cambi, A.; Figdor, C.G.

    2005-01-01

    In pathogen recognition by C-type lectins, several levels of complexity can be distinguished; these might modulate the immune response in different ways. Firstly, the pathogen-associated molecular pattern repertoire expressed at the microbial surface determines the interactions with specific recepto

  10. Lectin Digestibility and Stability of Elderberry Antioxidants to Heat Treatment In Vitro

    Directory of Open Access Journals (Sweden)

    Pilar Jiménez

    2017-01-01

    Full Text Available Elderberry contains healthy low molecular weight nutraceuticals and lectins which are sequence-related to the elderberry allergen Sam n1. Some of these lectins are type II ribosome-inactivating proteins. The sensitivity of native lectins present in elderberry fruits and bark to the proteolysis triggered by in vitro simulated gastric and duodenal fluids has been investigated. It was found that these lectins are refractory to proteolysis. Nonetheless, incubation for 5–10 min in a boiling water bath completely sensitized them to the hydrolytic enzymes in vitro. Under these conditions neither total Folin-Ciocalteau’s reagent reactive compounds, total anthocyanins and the mixture of cyanidin-3-glucoside plus cyanidin-3-sambubioside, nor antioxidant and free-radical scavenging activities were affected by more than 10% for incubations of up to 20 min. Therefore, short-time heat treatment reduces potential allergy-related risks deriving from elderberry consumption without seriously affecting its properties as an antioxidant and free-radical scavenging food.

  11. Ternary supramolecular quantum-dot network flocculation for selective lectin detection

    NARCIS (Netherlands)

    Oikonomou, Maria; Wang, Junyou; Carvalho, Rui Rijo; Velders, Aldrik H.

    2016-01-01

    We present a versatile, tuneable, and selective nanoparticle-based lectin biosensor, based on flocculation of ternary supramolecular nanoparticle networks (NPN), formed through the sequential binding of three building blocks. The three building blocks are β-cyclodextrin-capped CdTe quantum dots,

  12. Preoperative mannan-binding lectin pathway and prognosis in colorectal cancer

    DEFF Research Database (Denmark)

    Ytting, Henriette; Christensen, Ib Jarle; Jensenius, Jens Christian

    2005-01-01

    PURPOSE: Deficiency of the mannan-binding lectin (MBL) pathway of innate immunity is associated with increased susceptibility to infections. In patients with colorectal cancer (CRC), postoperative infection is associated with poor prognosis. The aim of the present study was to evaluate (1...

  13. Isolation and characterization of a novel lectin with antifungal and antiproliferative activities from Sophora alopecuroides seeds

    Institute of Scientific and Technical Information of China (English)

    Tinging Li; Xiaoli Yin; Dongliang Liu; Xiaojin Ma; Hui Lv; Surong Sun

    2012-01-01

    Sophora alopecuroides lectin (SAL),a novel lectin from the seeds of Sophora alopecuroides,was purified by ionexchange chromatography on diethylaminoethyl (DEAE)-and carboxymethyl (CM)-Sepharose columns,followed by gel filtration on a Sephadex 75 10/300 GL column.SAL was found to be a monomer of 39916.3 Da,as determined by tricine-sodium dodecyl sulphate-polyacrylamide gel electrophoresis and high-performance liquid chromato-graphy (HPLC).The N-terminal 10-amino acid sequence of SAL,KPWALSFSFG,resembles those of other legume lectins.SAL exhibits hemagglutinating activity against rabbit erythrocytes at 11.9 μg/ml.Its hemagglutinating activity is stable in the pH range 7-11 and in the temperature range 30-90℃,and is stimulated by Mn2+.The hemagglutinating activity of SAL is most potently inhibited by 50-mM D-galactose.SAL suppresses mycelial growth in Penicillium digitatum and Alternaria alternata;the IC50 of the antifungal activity toward P.digitatum and A.alternata were found to be 3.125 and 3.338 μM,respectively.SAL suppresses the proliferation of human cervical cancer cells (HeLa) at an ICso of 6.25 μM (P< 0.05).But it has no inhibiting effect on bacteria.This is the first report of a lectin from seeds of S.alopecuroides.

  14. Lotus corniculatus nodulation specificity is changed by the presence of a soybean lectin gene

    Science.gov (United States)

    van Rhijn P; Goldberg; Hirsch

    1998-08-01

    Plant lectins have been implicated as playing an important role in mediating recognition and specificity in the Rhizobium-legume nitrogen-fixing symbiosis. To test this hypothesis, we introduced the soybean lectin gene Le1 either behind its own promoter or behind the cauliflower mosaic virus 35S promoter into Lotus corniculatus, which is nodulated by R. loti. We found that nodulelike outgrowths developed on transgenic L. corniculatus plant roots in response to Bradyrhizobium japonicum, which nodulates soybean and not Lotus spp. Soybean lectin was properly targeted to L. corniculatus root hairs, and although infection threads formed, they aborted in epidermal or hypodermal cells. Mutation of the lectin sugar binding site abolished infection thread formation and nodulation. Incubation of bradyrhizobia in the nodulation (nod) gene-inducing flavonoid genistein increased the number of nodulelike outgrowths on transgenic L. corniculatus roots. Studies of bacterial mutants, however, suggest that a component of the exopolysaccharide surface of B. japonicum, rather than Nod factor, is required for extension of host range to the transgenic L. corniculatus plants.

  15. Lectin histochemistry of Kudoa septempunctata genotype ST3-infected muscle of olive flounder (Paralichthys olivaceus

    Directory of Open Access Journals (Sweden)

    Kang Jaeyoun

    2016-01-01

    Full Text Available The localization of carbohydrate terminals in Kudoa septempunctata ST3-infected muscle of olive flounder (Paralichthys olivaceus was investigated using lectin histochemistry to determine the types of carbohydrate sugar residues expressed in Kudoa spores. Twenty-one lectins were examined, i.e., N-acetylglucosamine (s-WGA, WGA, DSL-II, DSL, LEL, STL, mannose (Con A, LCA, PSA, galactose/N-acetylgalactosamine (RCA12, BSL-I, VVA, DBA, SBA, SJA, Jacalin, PNA, ECL, complex type N-glycans (PHA-E and PHA-L, and fucose (UEA-I. Spores encased by a plasmodial membrane were labeled for the majority of these lectins, with the exception of LCA, PSA, PNA, and PHA-L. Four lectins (RCA 120, BSL-I, DBA, and SJA belonging to the galactose/N-acetylgalactosamine group, only labeled spores, but not the plasmodial membrane. This is the first confirmation that various sugar residues are present in spores and plasmodial membranes of K. septempunctata ST3.

  16. Structural Insight into Multivalent Galactoside Binding to Pseudomonas aeruginosa Lectin LecA

    NARCIS (Netherlands)

    Visini, Ricardo; Jin, Xian; Bergmann, Myriam; Michaud, Gaelle; Pertici, Francesca; Fu, Ou; Pukin, Aliaksei; Branson, Thomas R.; Thies-Weesie, Dominique M E; Kemmink, Johan; Gillon, Emilie; Imberty, Anne; Stocker, Achim; Darbre, Tamis; Pieters, Roland J.; Reymond, Jean Louis

    2015-01-01

    Multivalent galactosides inhibiting Pseudomonas aeruginosa biofilms may help control this problematic pathogen. To understand the binding mode of tetravalent glycopeptide dendrimer GalAG2 [(Gal-β-OC6H4CO-Lys-Pro-Leu)4(Lys-Phe-Lys-Ile)2Lys-His-Ile-NH2] to its target lectin LecA, crystal structures of

  17. Enrichment and identification of glycoproteins in human saliva using lectin magnetic bead arrays.

    Science.gov (United States)

    Caragata, Michael; Shah, Alok K; Schulz, Benjamin L; Hill, Michelle M; Punyadeera, Chamindie

    2016-03-15

    Aberrant glycosylation of proteins is a hallmark of tumorigenesis and could provide diagnostic value in cancer detection. Human saliva is an ideal source of glycoproteins due to the relatively high proportion of glycosylated proteins in the salivary proteome. Moreover, saliva collection is noninvasive and technically straightforward, and the sample collection and storage is relatively easy. Although differential glycosylation of proteins can be indicative of disease states, identification of differential glycosylation from clinical samples is not trivial. To facilitate salivary glycoprotein biomarker discovery, we optimized a method for differential glycoprotein enrichment from human saliva based on lectin magnetic bead arrays (saLeMBA). Selected lectins from distinct reactivity groups were used in the saLeMBA platform to enrich salivary glycoproteins from healthy volunteer saliva. The technical reproducibility of saLeMBA was analyzed with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify the glycosylated proteins enriched by each lectin. Our saLeMBA platform enabled robust glycoprotein enrichment in a glycoprotein- and lectin-specific manner consistent with known protein-specific glycan profiles. We demonstrated that saLeMBA is a reliable method to enrich and detect glycoproteins present in human saliva.

  18. Innate signaling by the C-type lectin DC-SIGN dictates immune responses

    NARCIS (Netherlands)

    Dunnen, den J.; Gringhuis, S.I.; Geijtenbeek, T.B.H.

    2009-01-01

    Effective immune responses depend on the recognition of pathogens by dendritic cells (DCs) through pattern recognition receptors (PRRs). These receptors induce specific signaling pathways that lead to the induction of immune responses against the pathogens. It is becoming evident that C-type lectins

  19. Mannose-binding lectin genotypes and susceptibility to epstein-barr virus infection in infancy

    DEFF Research Database (Denmark)

    Friborg, Jeppe T; Jarrett, Ruth F; Koch, Anders

    2010-01-01

    In a cohort study of children <4 years of age in Greenland, mannose-binding lectin (MBL2) genotypes and Epstein-Barr virus (EBV) antibody levels were determined. EBV seropositivity was significantly lower and time to seroconversion increased in MBL-insufficient compared with MBL-sufficient childr...

  20. Toward a structure-based comprehension of the lectin pathway of complement

    DEFF Research Database (Denmark)

    Kjaer, Troels R; Thiel, Steffen; Andersen, Gregers R

    2013-01-01

    To initiate the lectin pathway of complement pattern recognition molecules bind to surface-linked carbohydrates or acetyl groups on pathogens or damaged self-tissue. This leads to activation of the serine proteases MASP-1 and MASP-2 resulting in deposition of C4 on the activator and assembly...

  1. Toward a structure-based comprehension of the lectin pathway of complement.

    Science.gov (United States)

    Kjaer, Troels R; Thiel, Steffen; Andersen, Gregers R

    2013-12-15

    To initiate the lectin pathway of complement pattern recognition molecules bind to surface-linked carbohydrates or acetyl groups on pathogens or damaged self-tissue. This leads to activation of the serine proteases MASP-1 and MASP-2 resulting in deposition of C4 on the activator and assembly of the C3 convertase. In addition MASP-3 and the non-catalytic MAp19 and MAp44 presumably play regulatory functions, but the exact function of the MASP-3 protease remains to be established. Recent functional studies have significantly advanced our understanding of the molecular events occurring as activation progresses from pattern recognition to convertase assembly. Furthermore, atomic structures derived by crystallography or solution scattering of most proteins acting in the lectin pathway and two key complexes have become available. Here we integrate the current functional and structural knowledge concerning the lectin pathway proteins and derive overall models for their glycan bound complexes. These models are used to discuss cis- versus trans-activation of MASP proteases and the geometry of C4 deposition occurring on glycans in the lectin pathway.

  2. Lectin binding patterns in hyperplastic and metaplastic bullock prostate tissues after diethylstilbestrol administration.

    Science.gov (United States)

    Fernández, P E; Barbeito, C G; Portiansky, E L; Gimeno, E J

    2004-03-06

    Hyperplasia and squamous metaplasia of the prostatic epithelium are conditions induced by oestrogens. Diethylstilbestrol (DES) has been banned from cattle used for beef production because of the health risks. The potential use of molecular markers for the detection of illegal oestrogen administration was evaluated by taking samples of prostatic tissue from control bullocks, bullocks which had been treated with oestrogens, and bullocks sacrificed 21 and 90 days after a single dose of DES. The expression of the glycoconjugates was examined by lectinhistochemistry and the lectin binding pattern was characterised in epithelium and connective tissue. In the animals sacrificed after 21 days there was an increase in the binding of one lectin (JAC) and there was an increase in the binding of one of the other lectins (DBA) in the animals sacrificed after 90 days. An increase in SWGA lectin staining was observed in the bullocks that had probably been treated with oestrogen and in the animals sacrificed 90 days after the inoculation with DES. There were also differences between the binding of SWGA in the control bullocks and the other groups.

  3. Purification of Colocasia esculenta lectin and determination of its anti-insect potential towards Bactrocera cucurbitae.

    Science.gov (United States)

    Thakur, Kshema; Kaur, Manpreet; Kaur, Satwinder; Kaur, Amritpal; Kamboj, Sukhdev Singh; Singh, Jatinder

    2013-01-01

    The present study reports the purification of a lectin from Colocasia esculenta (L.) Schott corms and evaluation of its anti-insect potential towards Bactrocera cucurbitae (Coquilett). The lectin was found to be specific towards N-acetyl-D-lactosamine (LacNac), a disaccharide and asialofetuin, a desialylated serum glycoprotein in hemagglutination inhibition assay. Asialofetuin was used as a ligand to purify Colocasia esculenta agglutinin (CEA) by affinity chromatography. The purity of CEA was ascertained by the presence of a single band in reducing SDS-PAGE at pH 8.3. The affinity purified CEA was employed in artificial diet bioassay of second instar larvae (64-72 hr old) of the B. cucurbitae at concentrations ranging between 10-160 microg ml(-1). The lectin significantly (p < 0.01) decreased the percent pupation and emergence with respect to control. Effect on various enzymes was studied by employing LC50 (51.6 microg ml(-1)) CEA in the artificial diet bioassay of second instar larvae. All the enzymes tested namely esterases, phosphatases (acid and alkaline), superoxide dismutases, catalase and glutathione-S-transferase showed a significant (p < 0.01, p < 0.05) increase in their enzyme and specific activities. These results showed that CEA affected normal growth and development and presented stress to the larvae, activating their detoxification and anti-oxidant systems. Thus, the lectin seems to be a useful candidate for the control measures of B. cucurbitae under the integrated pest management (IPM) system.

  4. Effect of Moringa oleifera lectin on development and mortality of Aedes aegypti larvae.

    Science.gov (United States)

    Coelho, Juliene S; Santos, Nataly D L; Napoleão, Thiago H; Gomes, Francis S; Ferreira, Rodrigo S; Zingali, Russolina B; Coelho, Luana C B B; Leite, Sônia P; Navarro, Daniela M A F; Paiva, Patrícia M G

    2009-11-01

    Aedes aegypti larvae have developed tolerance to many insecticides used for mosquito control. Moringa oleifera seeds contain a water-soluble lectin (WSMoL) and this paper reports the effect of M. oleifera seed extracts (MoE(1-15)) and WSMoL on development and survival of A. aegypti larvae. WSMoL peptide from in-gel trypsin digestion is also described. MoE(1-15) showed hemagglutinating activity and WSMoL had similarity with flocculating proteins from M. oleifera seeds. MoE(1) and MoE(3) delayed larval development which stopped in the third instar (L3) in MoE(6) and MoE(15). Significant (p<0.0001) larval mortality was only detected in MoE(15). Native WSMoL showed larvicidal activity (LC(50) 0.197 mg mL(-1)) and heated lectin, without hemagglutinating activity, did not kill fourth instar (L4) larvae. Optical microscopy showed that live L4 from MoE(1) presented underlying epithelium, increased gut lumen and hypertrophic segments; dead L4 from WSMoL were absent of underlying epithelium, had increased gut lumen and hypertrophic segments. The presence of hemagglutinating activity in the extracts suggests that soluble lectin promotes the delay of larval development and mortality; furthermore, the absence of larvicidal activity in heat-denatured WSMoL strengthens the involvement of lectin in this activity mechanism.

  5. Crystallization and preliminary X-ray characterization of a lectin from Cicer arietinum (chickpea)

    Energy Technology Data Exchange (ETDEWEB)

    Katre, Uma V.; Gaikwad, S. M. [Division of Biochemical Sciences, National Chemical Laboratory, Pune 411008 (India); Bhagyawant, S. S.; Deshpande, U. D. [School of Life Sciences, S. R. T. M. University, Nanded 431606 (India); Khan, M. I.; Suresh, C. G., E-mail: suresh@ems.ncl.res.in [Division of Biochemical Sciences, National Chemical Laboratory, Pune 411008 (India)

    2005-01-01

    The crystallization and characterization of a lectin isolated and purified from C. arietinum and possessing complex sugar specificity is reported. The lectin isolated from mature seeds of Cicer arietinum (CAL) agglutinates pronase-treated rabbit and human erythrocytes and its haemagglutination activity is inhibited by fetuin and desialated fetuin but not by simple monosaccharides or oligosaccharides. The purified lectin is a dimer of molecular weight 43 000 Da composed of two identical subunits (MW 21 500), as confirmed by SDS–PAGE. The lectin has been crystallized using the hanging-drop vapour-diffusion method at 295 K over a well solution containing 0.2 M sodium acetate, 0.1 M sodium phosphate buffer pH 6.5 and 14%(w/v) polyethylene glycol 8000. The triangular prism-shaped crystals belong to space group R3 and have unit-cell parameters a = b = 81.2, c = 69.4 Å. The diffraction data are 93.8% complete to 2.3 Å Bragg spacing with an R{sub merge} of 0.103.

  6. Mannan-binding lectin polymorphisms and serum levels in patients with endometriosis

    DEFF Research Database (Denmark)

    Kruse, Christina; Steffensen, Rudi; Nielsen, Hans J;

    2014-01-01

    OBJECTIVE: To investigate a possible association between endometriosis and low levels of mannan-binding lectin (MBL). STUDY DESIGN: Case-control study of blood samples from 100 patients with endometriosis compared with results from a group of 350 blood donors. RESULT: The frequency of MBL levels...... endometriosis and low levels of MBL....

  7. Second-generation nanofiltered plasma-derived mannan-binding lectin product

    DEFF Research Database (Denmark)

    Laursen, I.; Houen, G.; Højrup, P.

    2007-01-01

    BACKGROUND AND OBJECTIVES: Mannan-binding lectin (MBL) is an important component of the innate immune defence; it binds to carbohydrate structures on pathogenic micro-organisms resulting in complement activation and opsonization. Individuals with low MBL levels are at risk of recurrent and severe...

  8. Purification of a secreted lectin from Andrias davidianus skin and its antibacterial activity.

    Science.gov (United States)

    Qu, Min; Tong, Changqing; Kong, Liang; Yan, Xin; Chernikov, Oleg V; Lukyanov, Pavel A; Jin, Qiao; Li, Wei

    2015-01-01

    A lectin secreted from Andrias davidianus skin (ADL) was purified by affinity chromatography on porcine stomach mucin (type III) (PSM)-crosslinked albumin, followed by gel filtration on Sephadex G-100 and HPLC on TSK gel G3000PWXL. The purified lectin was found to be a dimeric protein, as revealed by SDS-PAGE and MALDI-TOF analysis. SDS-PAGE showed that the ADL protein had a molecular mass of 17 kDa. ADL produced an 8.5 kDa band when examined using SDS-PAGE under reducing conditions. ADL agglutinated native and trypsinized human B erythrocytes. The hemagglutination activity was inhibited by glycoproteins, such as PSM and asialo-PSM, but not by any of the monosaccharides tested. The activity was stable between 4 °C and 50 °C. Significant ADL activity was observed between pH 4–5. The lectin reaction did not depend on the presence of the divalent cation Ca2+ or Mg2+. The N-terminal ADL sequence was determined to be VGYTVGATPM. The lectin exhibited antibacterial activity, involving growth and respiration inhibition in Escherichia coli, Enterobacter aerogenes, Staphylococcus aureus, Bacillus subtilis and Shewanella sp. Furthermore, ADL showed inhibition activity against the yeast Saccharomyces cerevisiae. These findings suggest that ADL plays an important role in the innate immunity of A. davidianus on the body surface.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    Dendritic cells (DCs) sense the microenvironment through several types of receptors recognizing pathogen-associated molecular patterns. In particular, C-type lectins, expressed by distinct subsets of DCs, recognize and internalize specific carbohydrate antigen in a Ca(2+) -dependent manner. Targe...

  10. Developmental changes affecting lectin binding in the vomeronasal organ of domestic pigs, Sus scrofa.

    Science.gov (United States)

    Park, Junwoo; Lee, Wonho; Jeong, Chanwoo; Kim, Hwangryong; Taniguchi, Kazumi; Shin, Taekyun

    2012-01-01

    This study investigated the developmental changes of glycoconjugate patterns in the porcine vomeronasal organs (VNOs) and associated glands (Jacobson's glands) from prenatal (9 weeks of gestation) and postnatal (2 days after birth) to the sexually mature stage (6 months old). The VNO of pigs (Sus scrofa) was examined using the following: Dolichos biflorus agglutinin (DBA), Bandeiraea simplicifolia agglutinin isolectin B4 (BSI-B4), Triticum vulgaris agglutinin (WGA), Ulex europaeus agglutinin I (UEA-I), and soybean agglutinin (SBA). At the fetal stage, all lectins examined were detected mainly in the free border of the vomeronasal epithelium, but few (WGA and UEA-I) and or absent in the VNO cell bodies. At the postnatal and sexually mature stages, the reactivity of some lectins, including WGA, UEA-I, DBA and SBA, were shown to increase in the VNO sensory epithelium as well as the free border. The increased reactivity of lectins as development progressed was also observed in Jacobson's gland acini. These findings suggest that binding sites of lectins, including those of WGA, UEA-I, DBA, and SBA, increase during development from fetal to postnatal growth, possibly contributing to the increased ability of chemoreception in the pig.

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

    Science.gov (United States)

    Andrade, Camila G; Cabral Filho, Paulo E; Tenório, Denise P L; Santos, Beate S; Beltrão, Eduardo I C; 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.

  12. Mannose-binding lectin : The Dr. Jekyll and Mr. Hyde of the innate immune system

    NARCIS (Netherlands)

    Bouwman, Lee Hans

    2006-01-01

    The scope of the current thesis is to obtain insight in immunological aspects of transplantation and diabetes. This thesis underscores the current concept of collaboration between the innate and adaptive immune system by showing close interactions between both immune systems. Mannose binding lectin

  13. Using crystallographic water properties for the analysis and prediction of lectin-carbohydrate complex structures.

    Science.gov (United States)

    Modenutti, C; Gauto, D; Radusky, L; Blanco, J; Turjanski, A; Hajos, S; Marti, Ma

    2015-02-01

    Understanding protein-ligand interactions is a fundamental question in basic biochemistry, and the role played by the solvent along this process is not yet fully understood. This fact is particularly relevant in lectins, proteins that mediate a large variety of biological processes through the recognition of specific carbohydrates. In the present work, we have thoroughly analyzed a nonredundant and well-curated set of lectin structures looking for a potential relationship between the structural water properties in the apo-structures and the corresponding protein-ligand complex structures. Our results show that solvent structure adjacent to the binding sites mimics the ligand oxygen structural framework in the resulting protein-ligand complex, allowing us to develop a predictive method using a Naive Bayes classifier. We also show how these properties can be used to improve docking predictions of lectin-carbohydrate complex structures in terms of both accuracy and precision, thus developing a solid strategy for the rational design of glycomimetic drugs. Overall our results not only contribute to the understanding of protein-ligand complexes, but also underscore the role of the water solvent in the ligand recognition process. Finally, we discuss our findings in the context of lectin specificity and ligand recognition properties.

  14. Carbohydrate Detection and Lectin Isolation from Tegumental Tissue of Fasciola hepatica

    Directory of Open Access Journals (Sweden)

    MB Molaei Rad

    2010-02-01

    Full Text Available "nBackground: Fascioliasis is a chronic hepatic disease and may be resulted from mechani­cal/molecular parasite adhesion to host liver tissue. The aim of this study was to detect surface car­bohydrate and lectin, carbohydrate-binding protein isolation that might be responsible of this molecular binding."nMethods: The present experimental work was conducted in the Department of Medical Parasitol­ogy and Mycology, School of Public Health, Tehran University of Medical Sciences, Te­hran, Iran.  Fasciola hepatica parasites were collected from abattoir (Saman, Tehran, Iran and surface mannose-carbohydrate was detected by fluorescein isothiocyanate (FITC conju­gated lectin (Lentil. Lectin of tegumental tissue from F. hepatica was isolated by affinity chroma­tography and detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE."nResults: Mannose carbohydrate was observed on the surface of tegumental tissue from para­site under fluorescence microscope. Carbohydrate-binding protein or lectin with MW of 50 kDa also was isolated from homogenized tegument of helminth."nConclusion: These results are important for understanding of molecular pathogenesis of F. hepat­ica at the chronic phase of fascioliasis

  15. C-type lectin interactions with Schistosoma mansoni SEA : Molecular basis and function

    NARCIS (Netherlands)

    Liempt, van P.A.G.

    2007-01-01

    Outline of this thesis The studies described in this thesis have been performed to gain more insight in the recognition of Schistosoma mansoni glycans by C-type lectins and the consequences for dendritic cell mediated immune responses. As a first approach to understand the molecular interactions o

  16. Effects of mannose-binding lectin polymorphisms on irinotecan-induced febrile neutropenia

    NARCIS (Netherlands)

    J.M. van der Bol (Jessica); M.J.A. de Jonge (Maja); R.H.N. van Schaik (Ron); A. Sparreboom (Alex); M.A. van Fessem (Marianne); F.E. Geijn (Fleur); P.L.A. van Daele (Paul); J. Verweij (Jaap); S. Sleijfer (Stefan); A.H.J. Mathijssen (Ron)

    2010-01-01

    textabstractObjective. Mannose-binding lectin (MBL) is important in the innate immune response. MBL2 gene polymorphisms affect MBL expression, and genotypes yielding low MBL levels have been associated with an elevated risk for infections in hematological cancer patients undergoing chemotherapy. How

  17. The role of mannose-binding lectin (MBL) in paediatric oncology patients with febrile neutropenia

    NARCIS (Netherlands)

    F.N.J. Frakking; M.D. van de Wetering; N. Brouwer; K.M. Dolman; J. Geissler; B. Lemkes; H.N. Caron; T.W. Kuijpers

    2006-01-01

    Children with cancer often have fever during chemotherapy-induced neutropenia, but only some develop serious infectious complications. Mannose-binding lectin (MBL) deficiency might increase infection susceptibility in these children. MBL genotype and phenotype were prospectively determined in 110 pa

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

    OpenAIRE

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

    2010-01-01

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

  19. Feline lectin activity is critical for the cellular entry of feline infectious peritonitis virus.

    Science.gov (United States)

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

    2010-08-01

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

  20. Transmission-blocking antibodies against mosquito C-type lectins for dengue prevention.

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2014-02-01

    Full Text Available 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.

  1. Computational and experimental prediction of human C-type lectin receptor druggability

    Directory of Open Access Journals (Sweden)

    Jonas eAretz

    2014-07-01

    Full Text Available Mammalian C-type lectin receptors are involved in many aspects of immune cell regulation such as pathogen recognition, clearance of apoptotic bodies and lymphocyte homing. Despite a great interest in modulating C-type lectin receptor recognition of carbohydrates, the number of specific molecular probes is limited. To this end, we predicted the druggability of a panel of 22 C-type lectin receptors using DoGSiteScorer. The computed druggability scores of most structures were low, characterizing this family as either challenging or even undruggable. To further explore these findings, we employed a fluorine-based NMR screening of fragment mixtures against DC-SIGN, a receptor of pharmacological interest. To our surprise, we found many fragment hits associated with the carbohydrate recognition site (hit rate = 13.5%. An SPR-based follow-up assay confirmed 18 of these fragments (47% and equilibrium dissociation constants were determined. Encouraged by these findings we expanded our experimental druggability prediction to Langerin and MCL and found medium to high hit rates as well, being 15.7% and 10.0%, respectively. Our results highlight limitations of current in silico approaches to druggability assessment, in particular with regard to carbohydrate-binding proteins. In sum, our data indicate that small molecule ligands for a larger panel of C-type lectin receptors can be developed.

  2. Molecular characterization and expression analysis of a novel dual-CRD C-type lectin in kuruma shrimp (Marsupenaeus japonicus)

    Institute of Scientific and Technical Information of China (English)

    ZHANG Man; MAO Yong; WANG Jun; FENG Wenrong; SONG Xiaohong; SU Yongquan

    2015-01-01

    C-type lectins are among the most significant pattern recognition receptors (PRRs) found in invertebrate. They are a class of carbohydrate-binding proteins that can recognize specific sugar moieties on the surface of pathogens. In the present study, a novel C-type lecitn (termed MjLectin) from kuruma shrimp Marsupenaeus japonicus was identified. The full-length cDNA of MjLectin was 1 245 bp with a 1 011 bp open reading frame (ORF) that encoded a polypeptide of 336 amino acid residues. MjLectin consisted of two tandemly arrayed carbohydrate-recognition domains (CRDs), unlike other reported M. japonicus C-type lectins with only one CRD. It showed a high similarity to other shrimp dual-CRD lectins. Among the Ca2+-binding Site 2, the tripeptide motif dictating the carbohydrate binding specificity was exhibited as a rare mutant LPN (Leu134-Pro135-Asn136) in CRD1 and a traditional EPN (Glu299-Pro300-Asn301) in CRD2, respectively. MjLectin showed a specific expression pattern in both tissue and cellular levels, for its mRNA transcript was mainly expressed in the F-cells of the hepatopancreas. After white spot syndrome virus (WSSV) challenge (3.6×108 virions/μL), the expression of MjLectin in the hepatopancreas was up-regulated significantly at 48 h (P<0.01) compared with the control group. These results suggested that MjLectin might be involved in the innate immune defense against WSSV infection.

  3. Mannose-binding lectin deficiency and acute exacerbations of chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Woodruff PG

    2012-11-01

    Full Text Available Richard K Albert,1 John Connett,2 Jeffrey L Curtis,3,4 Fernando J Martinez,3 MeiLan K Han,3 Stephen C Lazarus,5 Prescott G Woodruff51Medicine Service, Denver Health and Department of Medicine, University of Colorado Denver, Denver, CO, 2Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, 3Pulmonary and Critical Care Medicine, Department of Medicine, University of Michigan, Ann Arbor, MI, 4Pulmonary and Critical Care Medicine, VA Medical Center, Ann Arbor, MI, 5Pulmonary and Critical Care Medicine, Department of Medicine, and Cardiovascular Research Institute, University of California, San Francisco, CA, USABackground: Mannose-binding lectin is a collectin involved in host defense against infection. Whether mannose-binding lectin deficiency is associated with acute exacerbations of chronic obstructive pulmonary disease is debated.Methods: Participants in a study designed to determine if azithromycin taken daily for one year decreased acute exacerbations had serum mannose-binding lectin concentrations measured at the time of enrollment.Results: Samples were obtained from 1037 subjects (91% in the trial. The prevalence of mannose-binding lectin deficiency ranged from 0.5% to 52.2%, depending on how deficiency was defined. No differences in the prevalence of deficiency were observed with respect to any demographic variable assessed, and no differences were observed in time to first exacerbation, rate of exacerbations, or percentage of subjects requiring hospitalization for exacerbations in those with deficiency versus those without, regardless of how deficiency was defined.Conclusion: In a large sample of subjects with chronic obstructive pulmonary disease selected for having an increased risk of experiencing an acute exacerbation of chronic obstructive pulmonary disease, only 1.9% had mannose-binding lectin concentrations below the normal range and we found no association between mannose-binding lectin

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-07-01

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

  5. Carbohydrate/glycan-binding specificity of legume lectins in respect to their proposed biological functions

    Directory of Open Access Journals (Sweden)

    Márcio Viana Ramos

    2000-01-01

    Full Text Available The lectins, proteins which specifically recognize carbohydrate moieties, have been extensively studied in many biochemical and structural aspects in order to establish the molecular basis of this non-catalytic event. On the other hand, their clinical and agricultural potentials have been growing fast. Although lectins, mainly those from legume plants, had been investigated for biological properties, studies about the physiological functions of lectins are scarce in literature. Therefore, despite the accumulated data on lectins (as proteins, the role played by these signalizing molecules is poorly discussed. In the light of our accumulated results on legume lectins, specially those obtained from plants belonging to the Diocleinae sub-tribe and available data in literature, we discuss here the main hypothesis of their functions according to their carbohydrate/glycan-binding specificity.As lectinas, proteinas que especificamente reconhecem estruturas que contém carboidratos, têm sido extensivamente estudadas em muitos aspectos bioquímicos e estruturais, objetivando estabelecer as bases moleculares deste evento não-catalítico. Por outro lado, os potenciais clínicos e agriculturais destas proteínas têm crescido rapidamente. Embora as lectinas, principalmente aquelas de legumes tenham sido bastante investigadas em suas propriedades biológicas, estudos sobre as funcões fisiológicas de lectinas são escassos na literatura. Além disto, a despeito da quantidade de dados acumulados sobre lectinas (como proteínas, o papel desempenhado por estas moléculas de sinalização é pobremente discutido. Valendo-se de nossos estudos sobre lectinas de leguminosas, principalmente da sub-tribo Diocleinae, e outros dados presentes na literatura, discutimos aqui, as principais hipóteses de suas funções com base na especificidade por carboidratos e glicanos complexos.

  6. Plant lectins, from ancient sugar-binding proteins to emerging anti-cancer drugs in apoptosis and autophagy.

    Science.gov (United States)

    Jiang, Q-L; Zhang, S; Tian, M; Zhang, S-Y; Xie, T; Chen, D-Y; Chen, Y-J; He, J; Liu, J; Ouyang, L; Jiang, X

    2015-02-01

    Ubiquitously distributed in different plant species, plant lectins are highly diverse carbohydrate-binding proteins of non-immune origin. They have interesting pharmacological activities and currently are of great interest to thousands of people working on biomedical research in cancer-related problems. It has been widely accepted that plant lectins affect both apoptosis and autophagy by modulating representative signalling pathways involved in Bcl-2 family, caspase family, p53, PI3K/Akt, ERK, BNIP3, Ras-Raf and ATG families, in cancer. Plant lectins may have a role as potential new anti-tumour agents in cancer drug discovery. Thus, here we summarize these findings on pathway- involved plant lectins, to provide a comprehensive perspective for further elucidating their potential role as novel anti-cancer drugs, with respect to both apoptosis and autophagy in cancer pathogenesis, and future therapy.

  7. Impact of mannose-binding lectin insufficiency on the course of cystic fibrosis: A review and meta-analysis

    National Research Council Canada - National Science Library

    Chalmers, James D; Fleming, Gillian B; Hill, Adam T; Kilpatrick, David C

    2011-01-01

    Mannose-binding lectin (MBL) is an innate immune protein produced by the liver. MBL binds to glycoconjugates containing mannose, fucose or N-acetylglucosamine that are present in a wide variety of bacteria, viruses and fungi...

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

    Science.gov (United States)

    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.

  9. Cloning and expression of a mannose-binding jacalin-related lectin from leaves of Japanese cycad (Cycas revoluta Thunb.).

    Science.gov (United States)

    Haraguchi, Tomokazu; Nomura, Keiichi; Yagi, Fumio

    2006-09-01

    Cycad leaf lectin (CRLL), a mannose-recognizing jacalin-related lectin (mJRL), was first cloned as a gymnosperm lectin and expressed. The cDNA sequence of CRLL (DDBJ, accession no. AB198328), coding 291 amino acid residues, has a tandem repeat of about 150 amino acids divided into N- and C-terminal domains as Japanese chestnut mJRL. Sequence alignment showed deletion and insertion of the sequence, and its putative carbohydrate-binding sites showed some differences from other JRLs. PCR analysis showed that this lectin was expressed in the cycad leaf but not in the root or seed. Recombinant CRLL (rCRLL) was expressed in Escherichia coli and purified by affinity chromatography after refolding procedures. Properties of active rCRLL appeared to be almost the same as those of native CRLL.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2012-01-01

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

  12. Mutational analysis of affinity and selectivity of kringle-tetranectin interaction. Grafting novel kringle affinity ontp the trtranectin lectin scaffold

    DEFF Research Database (Denmark)

    Graversen, Jonas Heilskov; Jacobsen, C; Sigurskjold, B W

    2000-01-01

    -type lectin-like domain of tetranectin, involving Lys-148, Glu-150, and Asp-165, which mediates calcium-sensitive binding to plasminogen kringle 4. Here, we investigate the effect of conservative substitutions of these and a neighboring amino acid residue. Substitution of Thr-149 in tetranectin....... This study provides further insight into molecular determinants of importance for binding selectivity and affinity of C-type lectin kringle interactions....

  13. Solanum tuberosum lectin inhibits Ehrlich ascites carcinoma cells growth by inducing apoptosis and G2/M cell cycle arrest.

    Science.gov (United States)

    Kabir, Syed Rashel; Rahman, Md Musfikur; Amin, Ruhul; Karim, Md Rezaul; Mahmud, Zahid Hayat; Hossain, M Tofazzal

    2016-06-01

    Recently, a lectin was purified from the potato cultivated in Bangladesh locally known as Sheel. In the present study cytotoxicity of the lectin against Ehrlich ascites carcinoma (EAC) cells was studied by MTT assay in vitro in RPMI-1640 medium and 8.0-36.0 % cell growth inhibition was observed at the range of 2.5-160 μg/ml protein concentration when incubated for 24 h. The lectin-induced apoptosis in EAC cells was confirmed by fluorescence and optical microscope. The apoptotic cell death was also confirmed by using caspase inhibitors. Cells growth inhibition caused by the lectin (36 %) was remarkably decreased to 7.6 and 22.3 % respectively in the presence of caspase-3 and -8 inhibitors. RT-PCR was used to evaluate the expression of apoptosis-related genes Bcl-X, p53, and Bax. An intensive expression of Bcl-X gene was observed in untreated control EAC cells with the disappeared of the gene in Sheel-treated EAC cells. At the same time, Bax gene expression appeared only in Sheel-treated EAC cells and the expression level of the p53 gene was increased remarkable after the treatment of EAC cells with the lectin. The lectin showed strong agglutination activity against EAC cells. Flow cytometry was used to study the cell cycle phases of EAC cells and it was observed that the lectin arrested the G2/M phase. In conclusion, Sheel lectin inhibited EAC cells growth by inducing apoptosis.

  14. HCV and HIV binding lectin, DC-SIGNR, is expressed at all stages of HCV induced liver disease.

    Science.gov (United States)

    Cole, G; Coleman, N; Soilleux, E

    2004-01-01

    The process by which hepatitis C virus (HCV) enters cells and the reason for its hepatotropism remain obscure. Recently, the human immunodeficiency virus (HIV) binding lectins, DC-SIGN and DC-SIGNR, were shown to bind HCV. This article reports the expression of DC-SIGN and DC-SIGNR in HCV related liver disease and discusses whether these lectins, in particular DC-SIGNR, are responsible for HCV hepatotropism.

  15. Penetration through the peritrophic matrix is a key to lectin toxicity against Tribolium castaneum.

    Science.gov (United States)

    Walski, Tomasz; Van Damme, Els J M; Smagghe, Guy

    2014-11-01

    In the last decades lectins have received a lot of attention as potential tools in pest control. Despite substantial progress in the field not all the factors determining insecticidal potency and selectivity of these proteins have been described. Recently, three lectins, RSA (Rhizoctonia solani agglutinin), SNA-I and SNA-II (Sambucus nigra agglutinin I and II) have been shown to be toxic to aphids and caterpillars. In this project we investigated if these lectins are also toxic against larvae and a cell line of the red flour beetle, Tribolium castaneum, a model organism and important pest of stored products. Furthermore, we analyzed the stability of the lectins in the larval gut and used confocal microscopy to compare their efficiency in passing through the peritrophic matrix (PM). We observed that all three lectins were toxic against the T. castaneum cell line and their effectiveness in vitro was in decreasing order SNA-II>SNA-I>RSA with the respective EC50 being 0.1, 0.5 and 3.6 μg/ml. Larvae feeding for 16 day on diets containing 2% RSA, 2% SNA-II and 2% SNA-I weighed 0.14 ± 0.07 mg, 0.67 ± 0.44 mg and 1.89 ± 0.38 mg, corresponding to approximately 7%, 36% and 80% of control larvae, respectively. As a consequence, RSA increased the time to adult emergence by over 3-fold, SNA-II by 1.9-fold and SNA-I by 1.2-fold. RSA and SNA-II were stable in the larval gut, while SNA-I was digested and excreted with the feces. Finally, confocal microscopy confirmed that RSA passed through the PM more efficiently than SNA-II. In conclusion, our data suggest that the lectin ability to pass through the PM, governed by molecule dimensions, charge and size of PM pores, is one of the features that determine the toxicity of these insecticidal proteins.

  16. Specific lectin biomarkers for isolation of human pluripotent stem cells identified through array-based glycomic analysis

    Institute of Scientific and Technical Information of China (English)

    Yu-Chieh Wang; Trevor R Leonardo; Ying Liu; Suzanne E Peterson; Louise C Laurent; Shinya Yamanaka; Jeanne F Loring; Masato Nakagawa; Ibon Garitaonandia; Ileana Slavin; Gulsah Altun; Robert M Lacharite; Kristopher L Nazor; Ha T Tran; Candace L Lynch

    2011-01-01

    Rapid and dependable methods for isolating human pluripotent stem cell (hPSC) populations are urgently needed for quality control in basic research and in cell-based therapy applications.Using lectin arrays,we analyzed glycoproteins extracted from 26 hPSC samples and 22 differentiated cell samples,and identified a small group of iectins with distinctive binding signatures that were sufficient to distinguish hPSCs from a variety of non-pluripotent cell types.These specific biomarkers were shared by all the 12 human embryonic stem cell and the 14 human induced pluripotent stem cell samples examined,regardless of the laboratory of origin,the culture conditions,the somatic cell type reprogrammed,or the reprogramming method used.We demonstrated a practical application of specific lectin binding by detecting hPSCs within a differentiated cell population with lectin-mediated staining followed by fluorescence microscopy and flow cytometry,and by enriching and purging viable hPSCs from mixed cell populations using lectin-mediated cell separation.Global gene expression analysis showed pluripotency-associated differential expression of specific fucosyltransferases and sialyltransferases,which may underlie these differences in protein glycosylation and lectin binding.Taken together,our results show that protein glycosylation differs considerably between pluripotent and non-pluripotent cells,and demonstrate that lectins may be used as biomarkers to monitor pluripotency in stem cell populations and for removal of viable hPSCs from mixed cell populations.

  17. Human neutrophil migration and activation by BJcuL, a galactose binding lectin purified from Bothrops jararacussu venom

    Directory of Open Access Journals (Sweden)

    Fernandes Luiz

    2011-01-01

    Full Text Available Abstract Background Neutrophil migration to an inflamed site constitutes the first line of the innate immune response against invading microorganisms. Given the crucial role of endogenous lectins in neutrophil mobilization and activation, lectins from exogenous sources have often been considered as putative modulators of leukocyte function. Lectins purified from snake venom have been described as galactoside ligands that induce erythrocyte agglutination and platelet aggregation. This study evaluated human neutrophil migration and activation by C-type lectin BJcuL purified from Bothrops jararacussu venom. Results Utilizing fluorescence microscopy, we observed that biotinylated-BJcuL was evenly distributed on the neutrophil surface, selectively inhibited by D-galactose. Lectin was able to induce modification in the neutrophil morphology in a spherical shape for a polarized observed by optical microscopy and exposure to BJcuL in a Boyden chamber assay resulted in cell migration. After 30 minutes of incubation with BJcuL we found enhanced neutrophil functions, such as respiratory burst, zymozan phagocytosis and an increase in lissosomal volume. In addition, BJcuL delays late apoptosis neutrophils. Conclusion These results demonstrate that BJcuL can be implicated in a wide variety of immunological functions including first-line defense against pathogens, cell trafficking and induction of the innate immune response since lectin was capable of inducing potent neutrophil activation.

  18. Pregnancy-related changes in the mouse oviduct and uterus revealed by differential binding of fluoresceinated lectins.

    Science.gov (United States)

    Lee, M C; Wu, T C; Wan, Y J; Damjanov, I

    1983-01-01

    The binding of 20 fluorescein isothiocyanate (FITC)-labeled lectins to various portions of the pregnant and non-pregnant murine oviduct and uterus was studied by fluorescence microscopy. Five lectins (from Ricinus communis (RCA-I), Maclura pomifera (MPA), Triticum vulgare (wheat germ-WGA), Bauhinia purpurea (BPA), and Ulex europeus (UEA-I] reacted differentially with the epithelium of pregnant as compared with the non-pregnant uterus. The binding of RCA-I, MPA and WGA delineated pregnancy-related changes in the distal oviduct and colliculus tubaris. WGA recognized also pregnancy related changes in the proximal oviduct. The reactivity of the remaining 15 lectins did not distinguish the pregnant and non-pregnant oviduct and uterus, although some of them served to identify specific components of the mouse genital tract. Thus, Soybean lectin (SBA) reacted almost exclusively with the colliculus tubaris. UEA-I alone reacted exclusively with the epithelium of the non-pregnant uterus. RCA-II reacted preferentially with the epithelium of the oviduct and uterus as compared with its weak reactivity with the stroma. Two lectins (from Pisum sativum and Lens culinaris) reacted selectively with stromal cells of the uterus and oviduct. Present data indicate that the differential binding properties of these FITC-labeled lectins can be exploited to identify certain components of the mouse oviduct and uterus and to indicate changes in the cell surface and/or cytoplasm in these structures during pregnancy.

  19. Differential expression of skin mucus C-type lectin in two freshwater eel species, Anguilla marmorata and Anguilla japonica.

    Science.gov (United States)

    Tsutsui, Shigeyuki; Yoshinaga, Tatsuki; Komiya, Kaoru; Yamashita, Hiroka; Nakamura, Osamu

    2016-08-01

    Two types of lactose-specific lectins, galectin (AJL-1) and C-type lectin (AJL-2), were previously identified in the mucus of adult Anguilla japonica. Here, we compared the expression profiles of these two homologous lectins at the adult and juvenile stages between the tropical eel Anguilla marmorata and the temperate eel A. japonica. Only one lectin, predicted to be an orthologue of AJL-1 by LC-MS/MS, was detected in the mucus of adult A. marmorata. We also found that an orthologous gene to AJL-2 was expressed at very low levels, or not at all, in the skin of adult A. marmorata. However, we detected the gene expression of an AJL-2-orthologue in the skin of juvenile A. marmorata, and a specific antibody also detected the lectin in the juvenile fish epidermis. These findings suggest that expression profiles of mucosal lectins vary during development as well as between species in the Anguilla genus.

  20. Mannose-binding lectin deficiency with eosinophilic meningoencephalitis due to Angiostrongylus cantonensis in children: a case series

    Directory of Open Access Journals (Sweden)

    de Paula-Almeida Olga

    2011-07-01

    Full Text Available Abstract Introduction Eosinophilic meningitis, a potentially fatal disease caused by Angiostrongylus cantonensis, is considered an emerging infectious disease. Case presentation Three Caucasian boys (aged five-years-old, 10-years-old and six-years-old with a diagnosis of eosinophilic meningoencephalitis caused by Angiostrongylus cantonensis were studied. Serum immunoglobulin A (IgA, IgM, IgG, and complements C3c and C4 levels were quantified by using an immunodiffusion technique. Immunoglobulin E in serum was quantified by nephelometry and mannose-binding lectin by time-resolved fluorometry. Mannose-binding lectin deficiency was observed in the three patients. The first patient showed a reduction in the levels of IgA and IgM and an increase in the values of IgE and C4. The second patient showed a reduction in mannose-binding lectin level with increased IgG, C4 and IgE levels, and the third patient showed a decrease in mannose-binding lectin level and increased levels of IgM and complement C3c as well as a low level of C4. Conclusions To the best of our knowledge, this is the first report of mannose-binding lectin deficiency associated with Angiostrongylus cantonensis meningoencephalitis in children, and it may contribute to the understanding of the participation of this component of the lectin pathway in the development of the disease.

  1. Carbohydrate binding properties of banana (Musa acuminata) lectin I. Novel recognition of internal alpha1,3-linked glucosyl residues.

    Science.gov (United States)

    Mo, H; Winter, H C; Van Damme, E J; Peumans, W J; Misaki, A; Goldstein, I J

    2001-05-01

    Examination of lectins of banana (Musa acuminata) and the closely related plantain (Musa spp.) by the techniques of quantitative precipitation, hapten inhibition of precipitation, and isothermal titration calorimetry showed that they are mannose/glucose binding proteins with a preference for the alpha-anomeric form of these sugars. Both generate precipitin curves with branched chain alpha-mannans (yeast mannans) and alpha-glucans (glycogens, dextrans, and starches), but not with linear alpha-glucans containing only alpha1,4- and alpha1,6-glucosidic bonds (isolichenan and pullulan). The novel observation was made that banana and plantain lectins recognize internal alpha1,3-linked glucosyl residues, which occur in the linear polysaccharides elsinan and nigeran. Concanavalin A and lectins from pea and lentil, also mannose/glucose binding lectins, did not precipitate with any of these linear alpha-glucans. This is, the authors believe, the first report of the recognition of internal alpha1,3-glucosidic bonds by a plant lectin. It is possible that these lectins are present in the pulp of their respective fruit, complexed with starch.

  2. Carbohydrate profiling of fungal cell wall surface glycoconjugates of Trichophyton tonsurans and other keratinophilic filamentous fungi using lectins.

    Science.gov (United States)

    Leal, André Ferraz Goiana; de Lima Neto, Reginaldo Gonçalves; Macêdo, Danielle Patrícia Cerqueira; Beltrão, Eduardo Isidoro Carneiro; Neves, Rejane Pereira

    2011-11-01

    Various researchers have concluded that lectins are useful reagents for the study of fungal cell wall surface glycoconjugates. In this study, we evaluated the expression of N-acetyl-D-glucosamine, L-fucose, D-galactose and glucose/mannose on the cell wall surface of Trichophyton tonsurans and other keratinophilic filamentous fungi, using a simple lectin-binding protocol. The fungal cultures used were isolated from soils obtained from public parks by the hair-bait technique. The lectin assays used concanavalin A (Con A), wheat germ agglutinin (WGA), Ulex europeus agglutinin I (UEA-I) and peanut agglutinin (PNA), all conjugated with horseradish peroxidase. Adhesive tape was placed sticky-side down over the fungal colony, gently pressed and then removed. The fungal-tape samples were incubated with the lectin for 1 h at 4 °C. Lectin binding was visualised using 3,3-diaminobendizine (DAB) and hydrogen peroxidase. There was a high expression of N-acetyl-D-glucosamine on the cell wall surface of all fungi species tested, whereas the expression of L-fucose, D-galactose and glucose/mannose demonstrated inter-specific variations. The lectin-binding assay presented in this article eliminates many of the laborious steps involved in other protocols. The amount and quality of the mycelium and spores immobilised by the adhesive tapes were suitable for obtaining the carbohydrate profile in glycoconjugates of the cell wall surface of filamentous fungi.

  3. Expression of endogenic lectins and their glycoligands in the tear fluid, human corneal and conjunctival epithelium under physiological and disease conditions

    OpenAIRE

    Hrdličková, Enkela

    2016-01-01

    Purpose: Lectins play an important role in many biological processes. The aim of this work was to analyse mainly the expression of endogenic lectins, such as galectins and plant lectin, e.g. Dolichos biflorus agglutinin (DBA), and their glycoligands in the tear fluid, human corneal and conjunctival epithelium in physiological and disease conditions. Further, we studied the human natural antibody against Galα1,3Gal-R, which is mainly responsible for hyperacute rejection of xenografts transplan...

  4. Effects of an extracted lectin from Citrullus colocynthis L. (Cucurbitaceae) on survival, digestion and energy reserves of Ectomyelois ceratoniae Zeller (Lepidoptera: Pyralidae)

    OpenAIRE

    Samar eRamzi

    2013-01-01

    Lectins are the heterogeneous proteins in plants that serve as storage proteins via defensive mechanisms against herbivores. In the current study, a lectin was extracted and purified from seeds of Citrullus colocynthis by Sepharose 4B-Galactose and DEAE-cellulose fast flow chromatographies. Different concentrations of the lectin were added to artificial diet of Ectomyelois ceratoniae larvae finding out its effect on some biological parameters, digestive physiology and amount of storage macrom...

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

    DEFF Research Database (Denmark)

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

    2001-01-01

    The mannan-binding lectin (MBL) pathway of complement activation has been established as the third pathway of complement activation. MBL is a carbohydrate-binding serum protein, which circulates in complex with serine proteases known as mannan-binding lectin associated serine proteases (MASPs...... activation. Therefore, in a generally applicable complement activation assay specific for the MBL pathway, the activity of the classical pathway must be inhibited. This can be accomplished by exploiting the finding that high ionic strength buffers inhibit the binding of C1q to immune complexes and disrupt...... the C1 complex, whereas the carbohydrate-binding activity of MBL and the integrity of the MBL complex is maintained under hypertonic conditions. In the assay described here, the specific C4b-depositing capacity of the MBL pathway was determined by incubating serum diluted in buffer containing 1 M Na...

  6. Mannose-binding lectin and maladies of the bowel and liver

    Institute of Scientific and Technical Information of China (English)

    Daniel L Worthley; Peter G Bardy; David L Gordon; Charles G Mullighan

    2006-01-01

    Mannose-binding lectin (MBL) is a pattern-recognition molecule that binds to characteristic carbohydrate motifs present on the surface of many different pathogens.MBL binding stimulates the immune system via the lectin pathway of complement activation. In certain clinical situations, often characterized by pre-existing immune compromise, MBL deficiency increases the risk of infectious and other disease-specific complications. Many of the key pathogenic processes inherent to common gastroenterological diseases, such as infection, immunological damage, and carcinogenesis, have been linked to MBL. This editorial reviews the biology of MBL, outlines key disease associations to document the breadth of influence of MBL, and finally, highlights the relevance of MBL to both gastroenterological health and disease.

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

    DEFF Research Database (Denmark)

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

    2011-01-01

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

  8. Two-dimensional photonic crystal sensors for visual detection of lectin concanavalin A.

    Science.gov (United States)

    Zhang, Jian-Tao; Cai, Zhongyu; Kwak, Daniel H; Liu, Xinyu; Asher, Sanford A

    2014-09-16

    We fabricated a two-dimensional (2-D) photonic crystal lectin sensing material that utilizes light diffraction from a 2-D colloidal array attached to the surface of a hydrogel that contains mannose carbohydrate groups. Lectin-carbohydrate interactions create hydrogel cross-links that shrink the hydrogel volume and decrease the 2-D particle spacing. This mannose containing 2-D photonic crystal sensor detects Concanavalin A (Con A) through shifts in the 2-D diffraction wavelength. Con A concentrations can be determined by measuring the diffracted wavelength or visually determined from the change in the sensor diffraction color. The concentrations are easily monitored by measuring the 2-D array Debye ring diameter. Our observed detection limit for Con A is 0.02 mg/mL (0.7 μM). The 2-D photonic crystal sensors are completely reversible and can monitor Con A solution concentration changes.

  9. In vitro screening of plant lectins and tropical plant extracts for anthelmintic properties.

    Science.gov (United States)

    Ríos-de Álvarez, L; Jackson, F; Greer, A; Bartley, Y; Bartley, D J; Grant, G; Huntley, J F

    2012-05-25

    Lectins are plant secondary metabolites (PSM) found in many forages and which may confer anthelmintic properties to gastrointestinal parasites through disrupting the development of parasitic larvae throughout its life cycle. In experiment 1, the ability of the plant lectins jacalin (JAC), concanavalin A (Con A), phytohemagglutinin E2L2 (PHA-E2L2), phytohemagglutinin L4 (PHA-L4), phytohemagglutinin E3L (PHA-E3L), kidney bean albumin (KBA), Robinia pseudoacacia agglutinin (RPA), Maackia amurensis lectin (MAA), Maclura pomifera agglutinin (MAA), Dolichos biflorus agglutinin (DBA), wheat germ agglutinin (WGA) and Galanthus nivalis agglutinin (GNA) to disrupt the feeding of the first stage larvae (L(1)) of the sheep gastro-intestinal nematodes (GIN) Teladorsagia circumcincta, Haemonchus contortus and Trichostrongylus colubriformis was investigated using a larval feeding inhibition test (LFIT). Only PHA-E3L, WGA and Con A had a potent effect on disrupting larval feeding of all of the three species of GIN investigated. The lectin concentration required to inhibit feeding in 50% of L(1) (IC50) was 7.3±1.2, 8.3±1.4 and 4.3±1.7 μg/ml for PHA-E3L; 59.1±32.4, 58.7±11.9 and 8.1±7.0 μg/ml for Con A and 78.9±11.2, 69.4±8.1 and 28.0±14.1 μg/ml for WGA for T. circumcincta, H. contortus and T. colubriformis larvae, respectively (P=0.006). The addition of the lectin inhibitors fetuin, glucose/mannose or N-acetylglucosamine for PHA-E3L, Con A and WGA, respectively, caused an increase in the proportion of larvae that had fed at all concentrations for PHA-E3L only. In experiment 2, the effect of extracts from the tropical plants Azadiractha indica, Trichanthera gigantea, Morus alba, Gliricidia sepium and Leucaena leucocephala on the feeding behaviour of H. contortus L(1,) was examined. A. indica, T. gigantea and M. alba failed to inhibit 50% of larvae from feeding at concentrations up to 10mg plant extract per ml. In contrast, both G. sepium and L. leucocephala demonstrated

  10. Influence of major surgery on the mannan-binding lectin pathway of innate immunity

    DEFF Research Database (Denmark)

    Ytting, Henriette; Christensen, Ib Jarle; Basse, L.

    2006-01-01

    The mannan-binding lectin (MBL) pathway of complement activation is important in host defence against pathogens and possibly against cancer. We investigated the effect of major surgery on two central components of the MBL pathway; MBL and the MBL-associated serine protease MASP-2, and for compari......The mannan-binding lectin (MBL) pathway of complement activation is important in host defence against pathogens and possibly against cancer. We investigated the effect of major surgery on two central components of the MBL pathway; MBL and the MBL-associated serine protease MASP-2...... comprised 27 patients undergoing elective, open surgery for colorectal cancer, and was included in order to cover blood sampling between days 2 and 6. As expected, the surgical stress induced a marked acute phase response, as evidenced by a large increase in IL-6 (18-fold) and CRP (13-fold) levels...... cohorts (r = 0.71, P surgery influenced only marginally the two...

  11. Boronic acid lectin affinity chromatography (BLAC). 2. Affinity micropartitioning-mediated comparative glycosylation profiling.

    Science.gov (United States)

    Monzo, Alex; Olajos, Marcell; De Benedictis, Lorenzo; Rivera, Zuly; Bonn, Guenther K; Guttman, András

    2008-09-01

    As a continuation of our work on boronic acid lectin affinity chromatography (BLAC), in this paper we introduce an automated affinity micropartitioning approach using combined boronic acid and concanavalin A (BLAC/Con A) resin-filled micropipette tips to isolate and enrich human serum glycoproteins. The N-linked oligosaccharides of the partitioned glycoproteins were removed by PNGase F enzyme digestion, followed by 8-aminopyrene-1,3,6-trisulfonic acid labeling. Capillary gel electrophoresis with blue LED-induced fluorescence detection was applied in a multiplexed format for comparative glycan profiling. The efficiency of BLAC affinity micropartitioning was compared with that of the individual lectin and pseudolectin affinity enrichment. Finally, we report on our findings in glycosylation differences in human serum samples from healthy and prostate cancer patients by applying BLAC/Con A micropipette tip-based enrichment and comparative multicapillary gel electrophoresis analysis of the released and labeled glycans.

  12. Six independent fucose-binding sites in the crystal structure of Aspergillus oryzae lectin.

    Science.gov (United States)

    Makyio, Hisayoshi; Shimabukuro, Junpei; Suzuki, Tatsuya; Imamura, Akihiro; Ishida, Hideharu; Kiso, Makoto; Ando, Hiromune; Kato, Ryuichi

    2016-08-26

    The crystal structure of AOL (a fucose-specific lectin of Aspergillus oryzae) has been solved by SAD (single-wavelength anomalous diffraction) and MAD (multi-wavelength anomalous diffraction) phasing of seleno-fucosides. The overall structure is a six-bladed β-propeller similar to that of other fucose-specific lectins. The fucose moieties of the seleno-fucosides are located in six fucose-binding sites. Although the Arg and Glu/Gln residues bound to the fucose moiety are common to all fucose-binding sites, the amino-acid residues involved in fucose binding at each site are not identical. The varying peak heights of the seleniums in the electron density map suggest that each fucose-binding site has a different carbohydrate binding affinity.

  13. Screening of Caatinga plants as sources of lectins and trypsin inhibitors.

    Science.gov (United States)

    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.

  14. Mannose-Binding Lectin Binds to Amyloid Protein and Modulates Inflammation

    Directory of Open Access Journals (Sweden)

    Mykol Larvie

    2012-01-01

    Full Text Available Mannose-binding lectin (MBL, a soluble factor of the innate immune system, is a pattern recognition molecule with a number of known ligands, including viruses, bacteria, and molecules from abnormal self tissues. In addition to its role in immunity, MBL also functions in the maintenance of tissue homeostasis. We present evidence here that MBL binds to amyloid β peptides. MBL binding to other known carbohydrate ligands is calcium-dependent and has been attributed to the carbohydrate-recognition domain, a common feature of other C-type lectins. In contrast, we find that the features of MBL binding to Aβ are more similar to the reported binding characteristics of the cysteine-rich domain of the unrelated mannose receptor and therefore may involve the MBL cysteine-rich domain. Differences in MBL ligand binding may contribute to modulation of inflammatory response and may correlate with the function of MBL in processes such as coagulation and tissue homeostasis.

  15. How a Plant Lectin Recognizes High Mannose Oligosaccharides1[C][OA

    Science.gov (United States)

    Garcia-Pino, Abel; Buts, Lieven; Wyns, Lode; Imberty, Anne; Loris, Remy

    2007-01-01

    The crystal structure of Pterocarpus angolensis seed lectin is presented in complex with a series of high mannose (Man) oligosaccharides ranging from Man-5 to Man-9. Despite that several of the nine Man residues of Man-9 have the potential to bind in the monosaccharide-binding site, all oligomannoses are bound in the same unique way, employing the tetrasaccharide sequence Manα(1–2)Manα(1–6)[Manα(1–3)]Manα(1–. Isothermal titration calorimetry titration experiments using Man-5, Man-9, and the Man-9-containing glycoprotein soybean (Glycine max) agglutinin as ligands confirm the monovalence of Man-9 and show a 4-times higher affinity for Man-9 when it is presented to P. angolensis seed lectin in a glycoprotein context. PMID:17556509

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

    Directory of Open Access Journals (Sweden)

    S.A. Alen’kina

    2016-05-01

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

  17. [The molecular-weight characteristics of the bacterial lectins and humus components in soil].

    Science.gov (United States)

    Votselko, S K; Iutinskaia, G A; Kovalenko, E A; Kucheriavaia, N S

    2000-01-01

    A method has been developed to determine the molecular-weight distribution of biologically active substances: bacterial lectins and soil humus compounds. The method based on the simultaneous centrifugation of samples and molecular weight standards in the density gradient of NaCl solutions or combined gradient of NaCl and CsCl solutions permits analysing biologically active substances: lectins, proteins, polysaccharides, protein-polysaccharide complexes, humus compounds in the interval of molecular weight of 13.7 kappa [symbol: see text] a to 2000 kappa [symbol: see text] a. The use of this method in the soil researches makes it possible to study the dynamics of change of molecular parameters of the soil organic matter depending on agrotechnical methods as well as to determine transformation regularities of microbial polysaccharides.

  18. Exquisite specificity of mitogenic lectin from Cephalosporium curvulum to core fucosylated N-glycans.

    Science.gov (United States)

    Inamdar, Shashikala R; Eligar, Sachin M; Ballal, Suhas; Belur, Shivakumar; Kalraiya, Rajiv D; Swamy, Bale M

    2016-02-01

    Lectins are carbohydrate binding proteins that are gaining attention as important tools for the identification of specific glycan markers expressed during different stages of the cancer. We earlier reported the purification of a mitogenic lectin from human pathogenic fungus Cephalosporium curvulum (CSL) that has complex sugar specificity when analysed by hapten inhibition assay. In the present study, we report the fine sugar specificity of CSL as determined by glycan array analysis. The results revealed that CSL has exquisite specificity towards core fucosylated N-glycans. Fucosylated trimannosyl core is the basic structure required for the binding of CSL. The presence of fucose in the side chain further enhances the avidity of CSL towards such glycans. The affinity of CSL is drastically reduced towards the non-core fucosylated glycans, in spite of their side chain fucosylation. CSL showed no binding to the tested O-glycans and monosaccharides. These observations suggest the unique specificity of CSL towards core fucosylated N-glycans, which was further validated by binding of CSL to human colon cancer epithelial and hepatocarcinoma cell lines namely HT29 and HepG2, respectively, that are known to express core fucosylated N-glycans, using AOL and LCA as positive controls. LCA and AOL are fucose specific lectins that are currently being used clinically for the diagnosis of hepatocellular carcinomas. Most of the gastrointestinal markers express core fucosylated N-glycans. The high affinity and exclusive specificity of CSL towards α1-6 linkage of core fucosylated glycans compared to other fucose specific lectins, makes it a promising molecule that needs to be further explored for its application in the diagnosis of gastrointestinal cancer.

  19. Synthetic Lectins: New Tools for Detection and Management of Prostate Cancer

    Science.gov (United States)

    2014-08-01

    death , over 30,000 per year. Thus, our long term goal is to develop synthetic lectin (SL) arrays for the detection and diagnosis of prostate cancer...structural motifs (i.e., diols) present on all Cancer Associated Glycans/Glycoproteins. The covalent interaction increases the affinity of the SL for...Associated Glycans/Glycoproteins; (2) probe the biochemical and biophysical basis for the glycan-SL interactions to enhance binding affinities and

  20. Effect of diets containing genetically modified potatoes expressing Galanthus nivalis lectin on rat small intestine.

    Science.gov (United States)

    Ewen, S W; Pusztai, A

    1999-10-16

    Diets containing genetically modified (GM) potatoes expressing the lectin Galanthus nivalis agglutinin (GNA) had variable effects on different parts of the rat gastrointestinal tract. Some effects, such as the proliferation of the gastric mucosa, were mainly due to the expression of the GNA transgene. However, other parts of the construct or the genetic transformation (or both) could also have contributed to the overall biological effects of the GNA-GM potatoes, particularly on the small intestine and caecum.