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Ogilvie, Mary L., JoAnn Wilson Byl y T. Kent Gartner. "Platelet Aggregation Is Stimulated by Lactose-lnhibitable Snake Venom Lectins". Thrombosis and Haemostasis 62, n.º 02 (1989): 704–7. http://dx.doi.org/10.1055/s-0038-1646887.
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SummaryFive lactose-specific lectins from snake venoms were tested for the ability to stimulate the aggregation of human platelets. Three of the lectins, bushmaster (Lachesis muta), cottonmouth (Aricistrodon piscivorous leukostoma) and rattlesnake (Crotalus atrox) lectins, consistently stimulated secretion and aggregation. Thrombolectin (Bothrops atrox) occasionally caused aggregation. Copperhead (Agkistrodon contortrix contortrix) lectin did not by itself cause platelet aggregation. Lactose, a specific inhibitor of hemagglutination mediated by these lectins was a potent inhibitor of lectin-induced aggregation. Antiserum specific for bushmaster lectin inhibited aggregation by bushmaster lectin. In contrast, the same antiserum and anti-cottonmouth lectin serum enhanced aggregation by low levels of the other lectins.A variety of substances were assayed in the aggregometer for the ability to inhibit aggregation in response to these lectins. Both secretion and aggregation were inhibited by PGI2 and PGEx. Furthermore, lectin-induced aggregation was completely blocked by trifluoperazine and partially blocked by indomethacin. Monoclonal antibodies specific for GP IIb/IIIa (AP2, A2A9, LJP5, LJCP8) but not monoclonals directed against other platelet membrane proteins (API and AP3) inhibited lectin-induced aggregation. The peptide Arg-Gly-Asp-Ser but not Arg-Ala-Asp-Ser was a potent inhibitor of aggregation.
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Kothari, Sajani, Rebecca Heineman y Rene Harrison. "Optimizing Lectin Staining Methodology to Assess Glycocalyx Composition of Legionella-Infected Cells". Undergraduate Research in Natural and Clinical Science and Technology (URNCST) Journal 7, n.º 7 (17 de julio de 2023): 1–10. http://dx.doi.org/10.26685/urncst.490.
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Introduction: Legionella is a gram-negative bacterium that replicates intracellularly within macrophages. Legionella utilizes effector proteins to hijack ER-Golgi vesicle trafficking to sustain proliferation in its intracellular niche. Legionella has a considerable influence on O-glycosylation but not N-glycosylation events in the Golgi of infected cells. This research aims to optimize the use of fluorescent lectins, which are proteins that bind carbohydrates, to effectively label host-cell glycocalyx during Legionella infection. Methods: Epifluorescence imaging or flow cytometry were used to optimize the lectin staining methodology. We noted that the most effective conditions for lectin-labeling were when live HeLa cells were incubated with lectins diluted in Hank’s balanced salt solution (HBSS) with 3% Bovine serum albumin (BSA) for 10-30 minutes at 4 °C. Results: Incubating suspended cells with lectins necessitated smaller lectin concentrations, whereas lectin labeling of adherent cells required considerably larger concentrations. Wheat germ agglutinin (WGA) lectin mean fluorescence intensity (MFI) was concentration-dependent, but Concanavalin A (ConA) and Maclura pomifera (MPA) MFIs did not alter substantially with increasing lectin concentrations. Discussion: The optimal lectin concentration required was lectin-specific and based on whether the lectin fluorescence was assessed using flow cytometry or epifluorescence. Furthermore, the use of phosphate-buffered saline (PBS) for lectin dilution, cell permeabilization for intracellular labelling, and incubation of lectins in fixed cells reduced productive labelling of lectins on cell surfaces because it inhibited the lectin's ability to effectively bind the associated carbohydrate structure. Conclusion: Further research using diverse lectins on U937 macrophages is necessary to reach a definitive conclusion on the effect of Legionella on the overall host-cell glycocalyx composition during infection of these relevant immune cells.
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Bonnardel, François, Julien Mariethoz, Serge Pérez, Anne Imberty y Frédérique Lisacek. "LectomeXplore, an update of UniLectin for the discovery of carbohydrate-binding proteins based on a new lectin classification". Nucleic Acids Research 49, n.º D1 (11 de noviembre de 2020): D1548—D1554. http://dx.doi.org/10.1093/nar/gkaa1019.
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Abstract Lectins are non-covalent glycan-binding proteins mediating cellular interactions but their annotation in newly sequenced organisms is lacking. The limited size of functional domains and the low level of sequence similarity challenge usual bioinformatics tools. The identification of lectin domains in proteomes requires the manual curation of sequence alignments based on structural folds. A new lectin classification is proposed. It is built on three levels: (i) 35 lectin domain folds, (ii) 109 classes of lectins sharing at least 20% sequence similarity and (iii) 350 families of lectins sharing at least 70% sequence similarity. This information is compiled in the UniLectin platform that includes the previously described UniLectin3D database of curated lectin 3D structures. Since its first release, UniLectin3D has been updated with 485 additional 3D structures. The database is now complemented by two additional modules: PropLec containing predicted β-propeller lectins and LectomeXplore including predicted lectins from sequences of the NBCI-nr and UniProt for every curated lectin class. UniLectin is accessible at https://www.unilectin.eu/
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Lakhtin, M., V. Lakhtin, V. Alyoshkin y S. Afanasyev. "Lectins of beneficial microbes: system organisation, functioning and functional superfamily". Beneficial Microbes 2, n.º 2 (1 de junio de 2011): 155–65. http://dx.doi.org/10.3920/bm2010.0014.
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In this review our last results and proposals with respect to general aspects of lectin studies are summarised and compared. System presence, organisation and functioning of lectins are proposed, and accents on beneficial symbiotic microbial lectins studies are presented. The proposed general principles of lectin functioning allows for a comparison of lectins with other carbohydrate-recognition systems. A new structure-functional superfamily of symbiotic microbial lectins is proposed and its main properties are described. The proposed superfamily allows for extended searches of the biological activities of any microbial member. Prospects of lectins of beneficial symbiotic microorganisms are discussed.
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Melgarejo, Luz Marina, Nohora Vega y Gerardo Pérez. "Isolation and characterization of novel lectins from Canavalia ensiformis DC and Dioclea grandiflora Mart. ex Benth. seeds". Brazilian Journal of Plant Physiology 17, n.º 3 (septiembre de 2005): 315–24. http://dx.doi.org/10.1590/s1677-04202005000300006.
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Two lectins were isolated from Canavalia ensiformis and Dioclea grandiflora seeds. Gel filtration produced a fraction corresponding to Con A or D. grandiflora lectin while erythroagglutination assays revealed a distinct fraction presenting a lectin that agglutinates human red blood cells (RBCs) but not rabbit RBCs. Hydrophobic interaction chromatography showed that the latter fraction yielded a protein that readily agglutinates human erythrocytes; the lectin was also purified by affinity chromatography on Lac-Sepharose showing similar properties to that of the Phenyl-Sepharose-purified lectin. Despite minor differences (carbohydrate content or A1%1cm), the two lectins showed similar molecular properties in that they consisted of two non-covalently linked monomers having a Mr of 29-30 kDa and their pI values indicated that both lectins were slightly acidic proteins. The C. ensiformis lectin (CEL-II) and D. grandiflora lectin (DGL-II) specifically recognised the H-type 2 blood group (alpha-L-Fuc (1-2)-beta-D-Gal (1-4)-beta-D-GlcNAc-O-R), while binding to H-type 1, H-type 3, H-type 4, Leª or Le y was weaker. Carbohydrate inhibition of erythroagglutination showed that simple sugars were weakly recognised by the lectins, if at all. The N-terminal region presented a unique sequence hitherto found only in some Diocleinae lectins (designated type II). The overall results confirmed the existence of a second distinct lectin type, phylogenetically close to Diocleinae species. The data indicate a functional similarity among lectins of this type which possesses distinctive characteristics differentiating them from "classical" Man/Glc lectins.
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Van Holle, Sofie y Els J. M. Van Damme. "Signaling through plant lectins: modulation of plant immunity and beyond". Biochemical Society Transactions 46, n.º 2 (22 de febrero de 2018): 217–33. http://dx.doi.org/10.1042/bst20170371.
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Lectins constitute an abundant group of proteins that are present throughout the plant kingdom. Only recently, genome-wide screenings have unraveled the multitude of different lectin sequences within one plant species. It appears that plants employ a plurality of lectins, though relatively few lectins have already been studied and functionally characterized. Therefore, it is very likely that the full potential of lectin genes in plants is underrated. This review summarizes the knowledge of plasma membrane-bound lectins in different biological processes (such as recognition of pathogen-derived molecules and symbiosis) and illustrates the significance of soluble intracellular lectins and how they can contribute to plant signaling. Altogether, the family of plant lectins is highly complex with an enormous diversity in biochemical properties and activities.
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Mewe, Marco, Denis Tielker, Robert Schönberg, Melitta Schachner, Karl-Erich Jaeger y Udo Schumacher. "Pseudomonas aeruginosa lectins I and II and their interaction with human airway cilia". Journal of Laryngology & Otology 119, n.º 8 (agosto de 2005): 595–99. http://dx.doi.org/10.1258/0022215054516313.
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The bacterium Pseudomonas aeruginosa (PA) produces two carbohydrate binding lectins, designated PA lectin-I and lectin-II (PA-IL, PA-IIL). Both lectins are used by the bacterium to adhere to the glycocalyx of mammalian cells. In addition, the lectins immobilize ciliary beat. The kinetics of ciliary beat inhibition by each individual lectin have been analysed; however, their joint action on cilia has not been reported. Here we demonstrate that PA-IL and PA-IIL inhibit ciliary beat in a similar time-dependent manner. If applied simultaneously, ciliary beat inhibition after five hours of incubation was weaker than if each lectin was applied separately. Thus it can be hypothesized that the lectins compete for the same binding site(s) of the glycocalyx. Sugar inhibition experiments demonstrate that D-galactose and L-fucose inhibit both lectins, although clear preferences of D-galactose for PA-IL and of L-fucose for PA-IIL exist. These interactions have to be kept in mind when designing sugar-based therapies.
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Lesman-Movshovich, Efrat, Batia Lerrer y Nechama Gilboa-Garber. "Blocking ofPseudomonas aeruginosalectins by human milk glycans". Canadian Journal of Microbiology 49, n.º 3 (1 de marzo de 2003): 230–35. http://dx.doi.org/10.1139/w03-027.
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The opportunistic human pathogen Pseudomonas aeruginosa produces a D-galactophilic (PA-IL) lectin and another lectin (PA-IIL) that binds L-fucose > D-arabinose > D-mannose in close association with its host-attacking factors. These lectins contribute to the virulence of P. aeruginosa by their involvement in the production, adhesion, and pathogenic effects of its biofilm on host cells. Therefore, they are considered targets for anti-Pseudomonas therapy. The present study compares their blocking by human milk samples with that of the plant lectin Con A. It demonstrates that human milk inhibits the hemagglutinating activities of the three lectins, with PA-IIL much more strongly inhibited than PA-IL or Con A. Using these lectins, Western blots of the milk samples accord with the hemagglutination inhibition data and disclose the distribution of the human milk glycoproteins that inhibit each lectin. The data of this paper reveal the high efficiency of human milk components in blocking the P. aeruginosa lectins and the usefulness of these lectins for detecting milk glycoprotein saccharides, which may protect the infant against infections.Key words: Pseudomonas aeruginosa, lectins, human milk, glycoproteins, Western blotting.
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Coelho, Luana Cassandra Breitenbach Barroso, Priscila Marcelino dos Santos Silva, Vera Lúcia de Menezes Lima, Emmanuel Viana Pontual, Patrícia Maria Guedes Paiva, Thiago Henrique Napoleão y Maria Tereza dos Santos Correia. "Lectins, Interconnecting Proteins with Biotechnological/Pharmacological and Therapeutic Applications". Evidence-Based Complementary and Alternative Medicine 2017 (2017): 1–22. http://dx.doi.org/10.1155/2017/1594074.
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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.
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Gerhardus, M. J. T., J. M. C. Baggen, W. P. W. Van Der Knaap y T. Sminia. "Analysis of surface carbohydrates of Trichobilharzia ocellata miracidia and sporocysts using lectin binding techniques". Parasitology 103, n.º 1 (agosto de 1991): 51–59. http://dx.doi.org/10.1017/s003118200005928x.
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Miracidia and in vitro-derived primary sporocysts of the avian schistosome Trichobilharzia ocellata were studied for the expression and the characteristics of glycoconjugate moieties comprising the surface coat. Using a panel of 9 peroxidase labelled lectins, several different lectin binding sites were demonstrated on the larvae. Fixed miracidia have binding sites for 7 of the lectins; wheat-germ agglutinin binds to both the ciliated plates and the tegumental ridges between them; the other 6 lectins bind to the plates only. Three of the miracidia-binding lectins, wheat-germ agglutinin, concanavalin A and peanut agglutinin, also bind to fixed sporocysts. Since the miracidial ridges are devoid of binding sites for concanavalin A and peanut agglutinin, whereas the sporocyst tegument binds these lectins, it appears that these sites become exposed during or shortly after transformation. In saturation experiments, low concentrations of peanut agglutinin and concanavalin A are bound more avidly by sporocysts than by miracidia, indicating a higher binding affinity of the former. The two larval forms do not differ in affinity for wheat-germ agglutinin but they have different binding capacities; when offered in high concentrations, more of this lectin is bound by sporocysts than by miracidia. Lectin binding was competitively inhibited by adding the appropriate free saccharides. Live larvae showed the same lectin binding pattern as did fixed specimens. Proteinase treatment reduced lectin binding to living and, to a lesser extent, to fixed larvae, suggesting that binding sites are constituents of proteoglycoconjugates. After SDS–PAGE of extracts from miracidia and sporocysts and subsequent Western blotting, some of the lectins failed to bind glycoproteins, others reacted with an array of bands. The patterns differed among the lectins and each lectin gave different patterns for miracidia and sporocysts. The results obtained with these two lectin-binding techniques support the conclusion that stage-specific proteoglycoconjugates occur at the surface of T. ocellata larvae.
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Levine, E., R. Werner y G. Dahl. "Cell-cell channel formation and lectins". American Journal of Physiology-Cell Physiology 261, n.º 6 (1 de diciembre de 1991): C1025—C1032. http://dx.doi.org/10.1152/ajpcell.1991.261.6.c1025.
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The oocyte cell-cell channel assay was used to investigate determinants of the rate of channel formation. After injection of connexin-specific mRNA, oocytes accumulate a pool of precursors from which cell-cell channels can form after oocytes are paired. Channel formation was found to be increased if oocytes are pretreated with lectins before pairing. Several lectins differing in their carbohydrate binding affinities can exert this effect. Lectin-specific sugars suppress the effect on cell-cell channel formation only if the sugar is mixed with the lectin before application to the oocyte. If the lectin is first bound to the oocyte and then the sugar is added, no significant inhibition is seen. The promotion of channel formation by lectins is enhanced by adding an incubation period in regular medium after lectin treatment, before pairing of the oocytes. Electron microscopic studies with gold-conjugated lectins show that the lectin receptors are clustered on the free membrane surface and are taken up in endocytotic vesicles. These data suggest that the observed acceleration of cell-cell channel formation by lectins can be attributed to the removal of steric hindrance, which is a consequence of clustering of the bulky glycoprotein lectin receptors as well as of the removal from the surface by endocytosis.
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WRIGHT, Lisa M., Els J. M. VAN DAMME, Annick BARRE, Anthony K. ALLEN, Fred VAN LEUVEN, Colin D. REYNOLDS, Pierre ROUGE y Willy J. PEUMANS. "Isolation, characterization, molecular cloning and molecular modelling of two lectins of different specificities from bluebell (Scilla campanulata) bulbs". Biochemical Journal 340, n.º 1 (10 de mayo de 1999): 299–308. http://dx.doi.org/10.1042/bj3400299.
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Two lectins have been isolated from bluebell (Scilla campanulata) bulbs. From their isolation by affinity chromatography, they are characterized as a mannose-binding lectin (SCAman) and a fetuin-binding lectin (SCAfet). SCAman preferentially binds oligosaccharides with α(1,3)- and α(1,6)-linked mannopyranosides. It is a tetramer of four identical protomers of approx. 13 kDa containing 119 amino acid residues; it is not glycosylated. The fetuin-binding lectin (SCAfet), which is not inhibited by any simple sugars, is also unglycosylated. It is a tetramer of four identical subunits of approx. 28 kDa containing 244 residues. Each 28 kDa subunit is composed of two 14 kDa domains. Both lectins have been cloned from a cDNA library and sequenced. X-ray crystallographic analysis and molecular modelling studies have demonstrated close relationships in sequence and structure between these lectins and other monocot mannose-binding lectins. A refined model of the molecular evolution of the monocot mannose-binding lectins is proposed.
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Folowosele, Morenikeji Tolulope, Oludele Olayemi Odekanyin, Adenike Oluwaseun Adefila, Sinaola Praise Oyepitan, Eniola Racheal Owolabi y Ayomide Ifeoluwa Alobaloye. "Chemical Modification and Denaturation Effects on the Hemagglutinating Activity of Two Pterocarpus Species Seeds Lectins". Chemical Science International Journal 33, n.º 3 (1 de mayo de 2024): 89–99. http://dx.doi.org/10.9734/csji/2024/v33i3896.
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Aims: Pterocarpus osun and Pterocarpus soyauxii seeds lectins were subjected to various chemical modifications in order to detect the amino acid residues involved in their hemagglutinating and sugar-binding activities. Methodology: The lectins were purified using salt precipitation and size exclusion chromatography. Hemagglutinating activity and sugar specificity of the lectins were also established. Chemical modification of arginine was done using phenylglyoxal hydrate, and 5,5- dithiobis-(2-nitrobenzoic acid) (DTNB) was used to modify cysteine. Phenylmethylsulfonyl fluoride (PMSF) was employed for serine modification and tryptophan residue was modified with N-bromosuccinimide (NBS). Denaturants effects on the hemagglutinating activity were carried out with chaotropic agents, acid, disulphide bridge reducer and cross-linker agent. Results: Pterocarpus osun seeds lectin is mannose specific while Pterocarpus soyauxii seeds lectin is galactose/lactose-binding lectin. Hemagglutinating activities of the two lectins were completely lost when tryptophan residue was modified with NBS and the loss was reversed by dialysis. Modifications of Cysteine, Arginine and Serine have no effect on the hemagglutinating activity of P. osun lectin. Nevertheless, the modifications of same amino acids slightly reduced the activity of P. soyauxii lectin, which dialysis and prolonged incubation were able to overturn. Mannose was found to bind and inhibit hemagglutinating activity of P. osun lectin in the presence of various modifiers but galactose and lactose could not inhibit the hemagglutinating activity of P. soyauxii lectin in the presence of modifiers. All denaturants employed significantly affected the hemagglutinating activity of the two lectins. However, the effects were reversible except for P. osun lectin denatured with 8M urea. Conclusion: The results revealed that tryptophan residue is essential for hemagglutinating activity of the Pterocarpus species seeds lectins studied in this research. Cysteine, Arginine and Serine are also needed for sugar binding by P. soyauxii lectin but not so important in P. osun sugar binding ability.
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Adamcová, Anežka, Kristian Holst Laursen y Nicolai Zederkopff Ballin. "Lectin Activity in Commonly Consumed Plant-Based Foods: Calling for Method Harmonization and Risk Assessment". Foods 10, n.º 11 (13 de noviembre de 2021): 2796. http://dx.doi.org/10.3390/foods10112796.
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Lectins are ubiquitous proteins characterized through their ability to bind different types of carbohydrates. It is well known that active lectins from insufficiently prepared legumes can cause adverse human health effects. The objective of this study was to determine the activity of lectins in samples across plant families representing commercially available edible plants, and the feasibility of inactivating lectins through soaking and boiling. Lectins were extracted from the plant families Adoxaceae, Amaranthaceae, Cannabaceae, Fabaceae, Gramineae, Lamiaceae, Linaceae, Pedaliaceae, and Solanaceae. A hemagglutination assay based on non-treated or trypsin treated rabbit erythrocytes was used to measure the lectin activity. The results showed the highest lectin activity in species from the Fabaceae family and demonstrated that soaking and boiling have an effect on the levels of active lectins. This is the first large study that combines lectin activity obtained from two different assays with raw and processed edible plants. In addition, we examined the current risk assessment, and regulations necessary for an adequate official reporting of results. We encourage the scientific community to further explore this field and agree on harmonized methods for analysis and interpretation, and hope that our methodology can initiate this development.
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Hatakeyama, Tomomitsu y Hideaki Unno. "Functional Diversity of Novel Lectins with Unique Structural Features in Marine Animals". Cells 12, n.º 14 (9 de julio de 2023): 1814. http://dx.doi.org/10.3390/cells12141814.
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Due to their remarkable structural diversity, glycans play important roles as recognition molecules on cell surfaces of living organisms. Carbohydrates exist in numerous isomeric forms and can adopt diverse structures through various branching patterns. Despite their relatively small molecular weights, they exhibit extensive structural diversity. On the other hand, lectins, also known as carbohydrate-binding proteins, not only recognize and bind to the diverse structures of glycans but also induce various biological reactions based on structural differences. Initially discovered as hemagglutinins in plant seeds, lectins have been found to play significant roles in cell recognition processes in higher vertebrates. However, our understanding of lectins in marine animals, particularly marine invertebrates, remains limited. Recent studies have revealed that marine animals possess novel lectins with unique structures and glycan recognition mechanisms not observed in known lectins. Of particular interest is their role as pattern recognition molecules in the innate immune system, where they recognize the glycan structures of pathogens. Furthermore, lectins serve as toxins for self-defense against foreign enemies. Recent discoveries have identified various pore-forming proteins containing lectin domains in fish venoms and skins. These proteins utilize lectin domains to bind target cells, triggering oligomerization and pore formation in the cell membrane. These findings have spurred research into the new functions of lectins and lectin domains. In this review, we present recent findings on the diverse structures and functions of lectins in marine animals.
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Arruda, Francisco Vassiliepe Sousa, Arthur Alves Melo, Mayron Alves Vasconcelos, Romulo Farias Carneiro, Ito Liberato Barroso-Neto, Suzete Roberta Silva, Francisco Nascimento Pereira-Junior et al. "Toxicity and Binding Profile of Lectins from the GenusCanavaliaon Brine Shrimp". BioMed Research International 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/154542.
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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 ofCanavaliagenus. In order to determine the toxicity, assays withArtemianauplii were performed. In addition, a fluorescence assay was carried out to evaluate the binding of lectins toArtemianauplii. 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 ofArtemianauplii. 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.
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Ahmmed, Mirja Kaizer, Shuva Bhowmik, Stephen G. Giteru, Md Nazmul Hasan Zilani, Parise Adadi, Shikder Saiful Islam, Osman N. Kanwugu et al. "An Update of Lectins from Marine Organisms: Characterization, Extraction Methodology, and Potential Biofunctional Applications". Marine Drugs 20, n.º 7 (29 de junio de 2022): 430. http://dx.doi.org/10.3390/md20070430.
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Lectins are a unique group of nonimmune carbohydrate-binding proteins or glycoproteins that exhibit specific and reversible carbohydrate-binding activity in a non-catalytic manner. Lectins have diverse sources and are classified according to their origins, such as plant lectins, animal lectins, and fish lectins. Marine organisms including fish, crustaceans, and mollusks produce a myriad of lectins, including rhamnose binding lectins (RBL), fucose-binding lectins (FTL), mannose-binding lectin, galectins, galactose binding lectins, and C-type lectins. The widely used method of extracting lectins from marine samples is a simple two-step process employing a polar salt solution and purification by column chromatography. Lectins exert several immunomodulatory functions, including pathogen recognition, inflammatory reactions, participating in various hemocyte functions (e.g., agglutination), phagocytic reactions, among others. Lectins can also control cell proliferation, protein folding, RNA splicing, and trafficking of molecules. Due to their reported biological and pharmaceutical activities, lectins have attracted the attention of scientists and industries (i.e., food, biomedical, and pharmaceutical industries). Therefore, this review aims to update current information on lectins from marine organisms, their characterization, extraction, and biofunctionalities.
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Battistella, Roberta, Marios Kritsilis, Hana Matuskova, Douglas Haswell, Anne Xiaoan Cheng, Anja Meissner, Maiken Nedergaard y Iben Lundgaard. "Not All Lectins Are Equally Suitable for Labeling Rodent Vasculature". International Journal of Molecular Sciences 22, n.º 21 (26 de octubre de 2021): 11554. http://dx.doi.org/10.3390/ijms222111554.
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The vascular system is vital for all tissues and the interest in its visualization spans many fields. A number of different plant-derived lectins are used for detection of vasculature; however, studies performing direct comparison of the labeling efficacy of different lectins and techniques are lacking. In this study, we compared the labeling efficacy of three lectins: Griffonia simplicifolia isolectin B4 (IB4); wheat germ agglutinin (WGA), and Lycopersicon esculentum agglutinin (LEA). The LEA lectin was identified as being far superior to the IB4 and WGA lectins in histological labeling of blood vessels in brain sections. A similar signal-to-noise ratio was achieved with high concentrations of the WGA lectin injected during intracardial perfusion. Lectins were also suitable for labeling vasculature in other tissues, including spinal cord, dura mater, heart, skeletal muscle, kidney, and liver tissues. In uninjured tissues, the LEA lectin was as accurate as the Tie2–eGFP reporter mice and GLUT-1 immunohistochemistry for labeling the cerebral vasculature, validating its specificity and sensitivity. However, in pathological situations, e.g., in stroke, the sensitivity of the LEA lectin decreases dramatically, limiting its applicability in such studies. This work can be used for selecting the type of lectin and labeling method for various tissues.
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Chen, C., H. J. Durrant, R. P. Newton y N. A. Ratcliffe. "A study of novel lectins and their involvement in the activation of the prophenoloxidase system in Blaberus discoidalis". Biochemical Journal 310, n.º 1 (15 de agosto de 1995): 23–31. http://dx.doi.org/10.1042/bj3100023.
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Endogenous and exogenous lectins have been found to activate the prophenoloxidase (proPO) system of the cockroach, Blaberus discoidalis, to the same extent as laminarin, a previously known microbial activator of proPO. The lectins can also further enhance this laminarin activation of the proPO system. Non-lectin proteins did not display any activation properties. The time course of proPO activation was studied after reconstitution of the reaction system using purified lectins, a trypsin-like enzyme, a trypsin inhibitor and partially purified lectin-binding proteins from the cockroach haemolymph. Lectin activation of the proPO system is probably not mediated by the lectin sugar-binding sites, as specific inhibitory sugars failed to abrogate the enhanced effect. The results suggest that alternative binding site(s) on the lectins may be involved in the proPO activation process. Evidence also suggests that several different lectins are involved in the regulation of the proPO system through separate receptors or binding molecules on the haemocytes, and that they exert their effects early in the sequence of events leading to conversion of proPO into its active form, possibly via regulation of serine proteases and protease inhibitors.
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Lim, Anita WW, André A. Neves, Sarah Lam Shang Leen, Pierre Lao-Sirieix, Elizabeth Bird-Lieberman, Naveena Singh, Michael Sheaff, Tony Hollingworth, Kevin Brindle y Peter Sasieni. "Lectins in Cervical Screening". Cancers 12, n.º 7 (16 de julio de 2020): 1928. http://dx.doi.org/10.3390/cancers12071928.
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Cervical screening in low-resource settings remains an unmet need. Lectins are naturally occurring sugar-binding glycoproteins whose binding patterns change as cancer develops. Lectins discriminate between dysplasia and normal tissue in several precancerous conditions. We explored whether lectins could be developed for cervical screening via visual inspection. Discovery work comprised lectin histochemistry using a panel of candidate lectins on fixed-human cervix tissue (high-grade cervical intraepithelial neoplasia (CIN3, n = 20) or normal (n = 20)), followed by validation in a separate cohort (30 normal, 25 CIN1, 25 CIN3). Lectin binding was assessed visually according to staining intensity. To validate findings macroscopically, near-infra red fluorescence imaging was conducted on freshly-resected cervix (1 normal, 7 CIN3), incubated with topically applied fluorescently-labelled lectin. Fluorescence signal was compared for biopsies and whole specimens according to regions of interest, identified by the overlay of histopathology grids. Lectin histochemistry identified two lectins—wheat germ agglutinin (WGA) and Helix pomatia agglutinin (HPA)—with significantly decreased binding to CIN3 versus normal in both discovery and validation cohorts. Findings at the macroscopic level confirmed weaker WGA binding (lower signal intensity) in CIN3 vs. normal for biopsies (p = 0.0308) and within whole specimens (p = 0.0312). Our findings confirm proof-of-principle and indicate that WGA could potentially be developed further as a probe for high-grade cervical disease.
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Tirta Ismaya, Wangsa, Raymond Rubianto Tjandrawinata y Heni Rachmawati. "Lectins from the Edible Mushroom Agaricus bisporus and Their Therapeutic Potentials". Molecules 25, n.º 10 (20 de mayo de 2020): 2368. http://dx.doi.org/10.3390/molecules25102368.
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The mushroom Agaricus bisporus secretes biologically active compounds and proteins with benefits for human health. Most reported proteins from A. bisporus are tyrosinases and lectins. Lectins are of therapeutic or pharmaceutical interest. To date, only limited information is available on A. bisporus lectins and lectin-like proteins. No therapeutic products derived from A. bisporus lectin (ABL) are available on the market despite its extensive exploration. Recently, A. bisporus mannose-binding protein (Abmb) was discovered. Its discovery enriches the information and increases the interest in proteins with therapeutic potential from this mushroom. Furthermore, the A. bisporus genome reveals the possible occurrence of other lectins in this mushroom that may also have therapeutic potential. Most of these putative lectins belong to the same lectin groups as ABL and Abmb. Their relationship is discussed. Particular attention is addressed to ABL and Abmb, which have been explored for their potential in medicinal or pharmaceutical applications. ABL and Abmb have anti-proliferative activities toward cancer cells and a stimulatory effect on the immune system. Possible scenarios for their use in therapy and modification are also presented.
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Detilleux, P. G., N. F. Cheville y B. J. Sheahan. "Ultrastructure and Lectin Histochemistry of Equine Cutaneous Histiolymphocytic Lymphosarcomas". Veterinary Pathology 26, n.º 5 (septiembre de 1989): 409–19. http://dx.doi.org/10.1177/030098588902600506.
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Tissues from subcutaneous lymphosarcomas and regional lymph nodes were examined by light and electron microscopy and by lectin histochemistry. Tumors were composed of two major cell types: small lymphocytes with few organelles and pleomorphic histiocytic cells with undulant surfaces, large numbers of cytoplasmic vacuoles, and many mitochondria with large crystalline inclusions. A large gram-positive coryneform bacterium was isolated from tumor nodules but was not identified morphologically in tumor tissues. Evaluation of sections of tumors with lectins as histochemical probes revealed three staining patterns: 1) lectin labeling histiocytic cells only (wheat germ, succinylated-wheat germ, Phaseolus vulgaris and soybean agglutinins); 2) lectins labeling histiocytic, interstitial and some lymphoid cells (concanavalin A, and Pisum sativum, Lens culinaris, and Ricinus communis I agglutinins); and 3) lectins failing to label any cell (peanut, Sophora japonica, and Ulex europaeus I agglutinins). In the lymph node, macrophages were labeled by lectins of groups 1 and 2; interdigitating reticular cells were labeled by group 2 lectins. Lectin staining of histiocytic cells in tumor tissues suggested that these were reactive cells and that lymphoid cells were the primary neoplastic component.
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Singh, Keerti, Lokita Agrawal, Rhea Gupta, Divyam Singh, Meghavi Kathpalia y Navkiran Kaur. "Lectins as a promising therapeutic agent for breast cancer: A review". Breast Disease 43, n.º 1 (20 de junio de 2024): 193–211. http://dx.doi.org/10.3233/bd-230047.
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Efficient treatment of cancer has been a subject of research by scientists for many years. Current treatments for cancer, such as radiotherapy, chemotherapy and surgery have been used in traditional combination therapy, but they have major setbacks like non-specificity, non-responsiveness in certain cancer types towards treatment, tumor recurrence, etc. Epidemiological data has shown that breast cancer accounts for 14% of cancer cases occurring in Indian women. In recent years, scientists have started to focus on the use of natural compounds like lectins obtained from various sources to counter the side effects of traditional therapy. Lectins like Sambucus nigra Agglutinin, Maackia amurensis lectin, Okra lectins, Haliclona caerulea lectin, Sclerotium rolfsii lectin, etc., have been discovered to have both diagnostic and therapeutic potential for breast cancer patients. Lectins have been found to have inhibitory effects on various cancer cell activities such as neo-angiogenesis, causing cell cycle arrest at the G1 phase, and inducing apoptosis. The major idea behind the use of lectins in cancer diagnostics and therapeutics is their capability to bind to glycosylated proteins that are expressed on the cell surface. This review focuses on an exploration of the roles of post-translational modification in cancer cells, especially glycosylation, and the potential of lectins in cancer diagnosis and therapeutics.
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Barre, Annick, Mathias Simplicien, Hervé Benoist, Els J. M. Van Damme y Pierre Rougé. "Mannose-Specific Lectins from Marine Algae: Diverse Structural Scaffolds Associated to Common Virucidal and Anti-Cancer Properties". Marine Drugs 17, n.º 8 (26 de julio de 2019): 440. http://dx.doi.org/10.3390/md17080440.
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To date, a number of mannose-specific lectins have been isolated and characterized from seaweeds, especially from red algae. In fact, man-specific seaweed lectins consist of different structural scaffolds harboring a single or a few carbohydrate-binding sites which specifically recognize mannose-containing glycans. Depending on the structural scaffold, man-specific seaweed lectins belong to five distinct structurally-related lectin families, namely (1) the griffithsin lectin family (β-prism I scaffold); (2) the Oscillatoria agardhii agglutinin homolog (OAAH) lectin family (β-barrel scaffold); (3) the legume lectin-like lectin family (β-sandwich scaffold); (4) the Galanthus nivalis agglutinin (GNA)-like lectin family (β-prism II scaffold); and, (5) the MFP2-like lectin family (MFP2-like scaffold). Another algal lectin from Ulva pertusa, has been inferred to the methanol dehydrogenase related lectin family, because it displays a rather different GlcNAc-specificity. In spite of these structural discrepancies, all members from the five lectin families share a common ability to specifically recognize man-containing glycans and, especially, high-mannose type glycans. Because of their mannose-binding specificity, these lectins have been used as valuable tools for deciphering and characterizing the complex mannose-containing glycans from the glycocalyx covering both normal and transformed cells, and as diagnostic tools and therapeutic drugs that specifically recognize the altered high-mannose N-glycans occurring at the surface of various cancer cells. In addition to these anti-cancer properties, man-specific seaweed lectins have been widely used as potent human immunodeficiency virus (HIV-1)-inactivating proteins, due to their capacity to specifically interact with the envelope glycoprotein gp120 and prevent the virion infectivity of HIV-1 towards the host CD4+ T-lymphocyte cells in vitro.
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Timoshenko, A. V., S. André, H. Kaltner, X. Dong y H. J. Gabius. "Generation of H2O2 by Human Neutrophils and Changes of Cytosolic Ca2+ and pH of Rat Thymocytes in Response to Galactoside-Binding Proteins (Lectins or Immunoglobulins)". Bioscience Reports 17, n.º 2 (1 de abril de 1997): 219–30. http://dx.doi.org/10.1023/a:1027389614391.
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In contrast to plant agglutinins, biological activities of animal/human lectins are not well defined yet. Testing a panel of seven mammalian carbohydrate-binding proteins we have found that the dimeric lectin from chicken liver (CL-16) was a stimulator of H2O2 release from human neutrophils as well as effector for induction of cytosolic Ca2+ and pH increase in rat thymocytes. Activity of this lectin was comparable to potent galactoside-specific plant lectins such as Viscum album L. agglutinin. The activities of the tested plant lectins depended significantly on their nominal carbohydrate specificity as well as on the source. The results indicate that endogenous lectins may be involved in the regulation of neutrophil and lymphocyte functions by elicitation of selective biosignaling reactions.
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Ramiro-Diaz, Juan, Alma Barajas-Espinosa, Erika Chi-Ahumada, Sandra Perez-Aguilar, David Torres-Tirado, Jesus Castillo-Hernandez, Maureen Knabb, Ana Barba de la Rosa y Rafael Rubio. "Luminal endothelial lectins with affinity for N-acetylglucosamine determine flow-induced cardiac and vascular paracrine-dependent responses". American Journal of Physiology-Heart and Circulatory Physiology 299, n.º 3 (septiembre de 2010): H743—H751. http://dx.doi.org/10.1152/ajpheart.00790.2009.
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Coronary blood flow applied to the endothelial lumen modulates parenchymal functions via paracrine effectors, but the mechanism of flow sensation is unknown. We and others have demonstrated that coronary endothelial luminal membrane (CELM) oligosaccharides and lectins are involved in flow detection, and we proposed that cardiac effects of coronary flow result from a reversible flow-modulated lectin-oligosaccharide interaction. Recently, glycosylated and amiloride-sensitive Na+/Ca++ channels (ENaCs) have been proposed to be involved in the flow-induced endothelial responses. Because N-acetylglucosamine (GlcNac) is one of the main components of glycocalyx oligosaccharides (i.e., hyaluronan [−4GlcUA β1–3GlcNAc β1−]n), the aim of this article is to isolate and define CELM GlcNac-binding lectins and determine their role in cardiac and vascular flow-induced effects. For this purpose, we synthesized a 460-kDa GlcNac polymer (GlcNac-Pol) with high affinity toward GlcNac-recognizing lectins. In the heart, intracoronary administration of GlcNac-Pol upon binding to CELM diminishes the flow-dependent positive inotropic and dromotropic effects. Furthermore, GlcNac-Pol was used as an affinity probe to isolate CELM GlcNac-Pol-recognizing lectins and at least 35 individual lectinic peptides were identified, one of them the β-ENaC channel. Some of these lectins could participate in flow sensing and in GlcNac-Pol-induced effects. We also adopted a flow-responsive and well-accepted model of endothelial-parenchymal paracrine interaction: isolated blood vessels perfused at controlled flow rates. We established that flow-induced vasodilatation (FIV) is blocked by endothelial luminal membrane (ELM) bound GlcNac-Pol, nitro-l-arginine methyl ester and indomethacin, amiloride, and hyaluronidase. The effect of hyaluronidase was reversed by infusion of soluble hyaluronan. These results indicate that GlcNac-Pol inhibits FIV by competing and displacing intrinsic hyaluronan bound to a lectinic structure such as the amiloride-sensitive ENaC. Nitric oxide and prostaglandins are the putative paracrine mediators of FIV.
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Chikalovets, Irina, Alina Filshtein, Valentina Molchanova, Tatyana Mizgina, Pavel Lukyanov, Olga Nedashkovskaya, Kuo-Feng Hua y Oleg Chernikov. "Activity Dependence of a Novel Lectin Family on Structure and Carbohydrate-Binding Properties". Molecules 25, n.º 1 (30 de diciembre de 2019): 150. http://dx.doi.org/10.3390/molecules25010150.
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A GalNAc/Gal-specific lectins named CGL and MTL were isolated and characterized from the edible mussels Crenomytilus grayanus and Mytilus trossulus. Amino acid sequence analysis of these lectins showed that they, together with another lectin MytiLec-1, formed a novel lectin family, adopting β-trefoil fold. In this mini review we discuss the structure, oligomerization, and carbohydrate-binding properties of a novel lectin family. We describe also the antibacterial, antifungal, and antiproliferative activities of these lectins and report about dependence of activities on molecular properties. Summarizing, CGL, MTL, and MytiLec-1 could be involved in the immunity in mollusks and may become a basis for the elaboration of new diagnostic tools or treatments for a variety of cancers.
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Vrcić, H., B. Horvat y I. Damjanov. "Lectin histochemistry of mouse vagina during the estrous cycle." Journal of Histochemistry & Cytochemistry 39, n.º 12 (diciembre de 1991): 1685–92. http://dx.doi.org/10.1177/39.12.1940320.
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Estrous cycle-related histochemical changes in the vaginal epithelium of sexually mature female mice were studied with 30 fluorescein isothiocyanate (FITC)-labeled lectins. On the basis of the staining pattern the lectins were divided into five groups: I, seventeen lectins that reacted with mucinous surface layer of proestrus. This group comprised two subgroups: Ia, seven lectins that reacted exclusively with the mucinous layer, and Ib, ten lectins that reacted with mucinous cells and the underlying squamous epithelium of proestrus; II, two lectins that reacted with squamous epithelium of proestrus only but were unreactive with mucinous cells; III, three lectins that reacted in a phase-specific manner with squamous epithelium; IV, six lectins that showed increased luminal surface reactivity in diestrus and/or metestrus; and V, eleven lectins that were unreactive with vaginal epithelium. These data indicate that the cyclic changes in the morphology of the vaginal epithelium are accompanied by distinct lectin reactivity patterns.
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C. Torres, Jose, Jose G. Hernandez, Edwin C. Hernandez, Jessica A. Braga, Cicero Cavalcante, Myriam J. Ortega y Francisco R. Da Silva. "EVALUATION OF ANOMERICRECOGNITION IN GALACTOSE BINDING LECTINS USING CROSSLINKED HEMICELLULOSE: A COMPARATIVE STUDY THROUGH AFFINITY CHROMATOGRAPHY". International Journal of Advanced Research 9, n.º 07 (31 de julio de 2021): 391–400. http://dx.doi.org/10.21474/ijar01/13138.
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The isolation of lectins by affinity chromatography with crosslinked hemicelluloses has been a common practice because of the variety of glycosides that they present, improving the isolation of different kinds of lectins, such as the galactose ligands.Lectins affinity for carbohydrates is so specific that a simple configuration of the chiral carbon can affect affinity, and there are lectins that are more related to alfa-galactosidic than beta-galactosidic residues, setting up that way, an anomeric recognition.The anomeric configuration of galactose residuesseems to have biological importance related to the behavior of some diseases and physiological processes. This work aimed to assess the anomeric recognition of two lectins reported as β-galactose ligands (PNA and ricin) and two lectins reported as α-galactose ligands (frutalin and jacalin) in two types of hemicellulose (xyloglucan of Tamarindus indica and galactomannan of Caesalpinia pulcherrima), subsequently crosslinked and used as chromatographic matrices. As a result,chromatographic profiles and retained fractions suggested preferential anomeric recognition by lectins for the hemicelluloses crosslinked. The galactomannan matrix retained 0,5mg of PNA lectin and 2,3mg of ricin lectin; meanwhile, the xyloglucan matrix retained 3,4mg of PNA and 3,2mg of ricin; results obtained by applying 5 mg of lectin. Ricin expresses a visible flexibility in anomeric recognition, while PNA shows a restricted recognition of β-galactose residues.Frutalin and jacalin did not show recognition of the xyloglucan matrix. This work proposes using hemicellulose reticles with epichlorohydrin as affinity chromatographic matrices for anomeric studies on recognizing galactose binding lectins.
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Rauschenberg, Melanie, Eva-Corrina Fritz, Christian Schulz, Tobias Kaufmann y Bart Jan Ravoo. "Molecular recognition of surface-immobilized carbohydrates by a synthetic lectin". Beilstein Journal of Organic Chemistry 10 (16 de junio de 2014): 1354–64. http://dx.doi.org/10.3762/bjoc.10.138.
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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.
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Thurston, G., P. Baluk, A. Hirata y D. M. McDonald. "Permeability-related changes revealed at endothelial cell borders in inflamed venules by lectin binding". American Journal of Physiology-Heart and Circulatory Physiology 271, n.º 6 (1 de diciembre de 1996): H2547—H2562. http://dx.doi.org/10.1152/ajpheart.1996.271.6.h2547.
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Plasma leakage in inflammation results from intercellular gaps that form in the endothelium of venules. These gaps and related morphological changes in endothelial cells are not readily seen by light microscopy. In this study we sought to visualize such changes by using the selective binding properties of plant lectins. Acute inflammation was induced in the trachea of pathogen-free F344 rats by injecting substance P intravenously, and 1, 3, or 10 min later the vasculature was perfused with fixative followed by a biotinylated lectin. Lectin binding was localized by avidinbiotin complex-peroxidase histochemistry and viewed in tracheal whole mounts by differential-interference contrast microscopy. The binding patterns of the 20 lectins tested fell into 4 groups. Most of the lectins either bound uniformly to the endothelium of normal and inflamed venules (group 1, e.g., Lycopersicon esculentum lectin) or bound weakly or not at all to venules (group 2, e.g., Maackia amurensis I lectin). The uniform binding of group 1 lectins not only revealed the overall vascular architecture but also made visible intercellular gaps and fingerlike processes at endothelial cell borders in inflamed venules. In postcapillary venules after substance P, the fingerlike processes were present along an average of 32% of the endothelial cell perimeter at 1 min, 25% at 3 min, and 7% at 10 min, compared with a baseline value of 2%. A third group of lectins (group 3, e.g., concanavalin A) bound selectively to focal patches of inflamed venules but bound weakly to normal venules. The fourth group (group 4, e.g., Ricinus communis I lectin) bound preferentially to focal patches in inflamed venules and also bound uniformly to normal venules. The focal binding of group 3 and 4 lectins coincided with sites of plasma leakage marked by extravasation of the particulate tracer monastral blue and was associated with subendothelial components of the vessel wall. We conclude that selected lectins reveal novel features of focal sites of plasma leakage, endothelial gaps, and fingerlike processes at endothelial cell borders in inflamed venules.
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Raposo, Cláudia D., André B. Canelas y M. Teresa Barros. "Human Lectins, Their Carbohydrate Affinities and Where to Find Them". Biomolecules 11, n.º 2 (29 de enero de 2021): 188. http://dx.doi.org/10.3390/biom11020188.
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Lectins are a class of proteins responsible for several biological roles such as cell-cell interactions, signaling pathways, and several innate immune responses against pathogens. Since lectins are able to bind to carbohydrates, they can be a viable target for targeted drug delivery systems. In fact, several lectins were approved by Food and Drug Administration for that purpose. Information about specific carbohydrate recognition by lectin receptors was gathered herein, plus the specific organs where those lectins can be found within the human body.
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Ferreira, Hugo Jefferson, Evandro Moreira de Almeida, Wildson Max Barbosa da Silva, Edson Holanda Teixeira y Luiz Gonzaga do Nascimento Neto. "Molecular Mechanisms Involved in the Antitumor Activity of Isolated Lectins from Marine Organisms: A Systematic Review". Current Drug Targets 21, n.º 6 (24 de abril de 2020): 616–25. http://dx.doi.org/10.2174/1389450120666191122113850.
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Introduction: Tumor cells may present several molecular alterations that favor their malignancy, among which there is the expression of tumor-related antigens, such as truncated T-glycans, Thomsen-nouvelle, sialyl-Lewis X and sialyl Tn, which may help in the diagnosis and treatment using specific target molecules. Lectins are ubiquitous proteins capable of interacting with specific carbohydrates. Lectins isolated from marine organisms have important characteristics such as low immunogenicity and can bind to complex glycans compared to plant lectins. Objective: This work evaluated, through a systematic review, the molecular mechanisms of antitumor activity of lectins isolated from marine organisms. Methodology: The Pubmed, Lilacs, Science Direct, Wiley and Scopus databases were reviewed using the descriptors: marine lectin and cancer. Articles in English, published between January 2008 and December 2018, which proposed the molecular mechanisms of anticancer activity of lectins from marine organisms were eligible for the study. Results: 17 articles were eligible. The lectins showed promising performance against cancer cells, presenting specific cytotoxicity for some types of malignant cells. The articles presented several lectins specific to different carbohydrates, modulating: pro and anti-apoptotic proteins, transcription factor E2F-1, via mitogen-activated protein kinase. In addition, exogenous lectin expression in cancer cells has been shown to be a promising way to treat cancer. Conclusion: This review showed the various studies that described the molecular mechanisms caused by marine lectins with antineoplastic potential. This knowledge is relevant for the development and use of the next generations of lectins isolated from marine organisms, supporting their potential in cancer treatment.
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Colyer, J., M. J. G. Farthing, P. J. Kumar, M. L. Clark, A. D. Ohannesian y N. M. Waldron. "Reappraisal of the ‘lectin hypothesis' in the aetiopathogenesis of coeliac disease". Clinical Science 71, n.º 1 (1 de julio de 1986): 105–10. http://dx.doi.org/10.1042/cs0710105.
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1. The agglutinating properties of a crude gluten digest, purified gliadin fractions and established plant lectins were investigated using mammalian erythrocytes, rat enterocytes and normal and coeliac human enterocytes as the target systems. 2. Gliadin preparations failed to cause agglutination of any of the cells tested, whereas established pure plant lectins were active cell agglutinins. 3. These studies indicate that gliadin peptides do not interact with intestinal cells in a polyvalent, lectin-like manner and as such cannot be regarded as true lectins. 4. Mucosal damage in coeliac disease is unlikely therefore to be related to lectin-like activity of gliadin.
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Ooi, Linda SM, Hexiang Wang, T. B. Ng y Vincent EC Ooi. "Isolation and characterization of a mannose-binding lectin from leaves of the Chinese daffodil Narcissus tazetta". Biochemistry and Cell Biology 76, n.º 4 (1 de agosto de 1998): 601–8. http://dx.doi.org/10.1139/o98-022.
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A mannose-binding lectin was isolated from leaves of the Chinese daffodil Narcissus tazetta (family Amaryllidaceae) using a procedure that comprised extraction with aqueous buffer, ammonium sulfate precipitation, ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel Blue gel and mannose-agarose, and FPLC-gel filtration on Superose 12. The lectin was adsorbed on mannose-agarose and unadsorbed on DEAE-cellulose and Affi-gel Blue gel. It was an unglycosylated homodimer with a molecular mass of 26 kDa. Analysis of the N-terminal sequence of the N. tazetta lectin revealed considerable homology to lectins from the daffodil Narcissus pseudonarcissus, the snowdrop Galanthus nivalis (family Amaryllidaceae), the tulip Tulipa, and Kidachi aloe Aloe arborescens (family Liliaceae), and the orchid lectins (family Orchidaceae). The most striking likeness exists among the Amaryllidaceae lectins. The N. tazetta lectin exhibits hemagglutinating activity toward rabbit erythrocytes.Key words: daffodil, mannose-binding lectin, agglutinin.
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GRUBHOFFER, L., V. KOVÁŘ y N. RUDENKO. "Tick lectins: structural and functional properties". Parasitology 129, S1 (octubre de 2004): S113—S125. http://dx.doi.org/10.1017/s0031182004004858.
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Few papers have been published on tick lectins so far, and therefore more data are needed to complete the mosaic of knowledge of their structural and functional properties. Tissue-specific lectin/haemagglutinin activities of both soft and hard ticks have been investigated. Some tick lectins are proteins with binding affinity for sialic acid, various derivatives of hexosamines and different glycoconjugates. Most tick lectin/haemagglutinin activities are blood meal enhanced, and could serve as molecular factors of self/non-self recognition in defence reactions against bacteria or fungi, as well as in pathogen/parasite transmission. Dorin M, the plasma lectin ofOrnithodoros moubata, is the first tick lectin purified so far from tick haemolymph, and the first that has been fully characterized. Partial characterization of other tick lectins/haemagglutinins has been performed mainly with respect to their carbohydrate binding specificities and immunochemical features.
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Chen, Pengyu, Kristof De Schutter, Els J. M. Van Damme y Guy Smagghe. "Can Plant Lectins Help to Elucidate Insect Lectin-Mediated Immune Response?" Insects 12, n.º 6 (27 de mayo de 2021): 497. http://dx.doi.org/10.3390/insects12060497.
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Lectins are carbohydrate-binding proteins that recognize and selectively bind to specific sugar structures. This group of proteins is widespread in plants, animals, and microorganisms, and exerts a broad range of functions. Many plant lectins were identified as exogenous stimuli of vertebrate immunity. Despite being the largest and most diverse taxon on earth, the study of lectins and their functions in insects is lagging behind. In insects, research on lectins and their biological importance has mainly focused on the C-type lectin (CTL) family, limiting our global understanding of the function of insect lectins and their role in insect immunity. In contrast, plant lectins have been well characterized and the immunomodulatory effects of several plant lectins have been documented extensively in vertebrates. This information could complement the missing knowledge on endogenous insect lectins and contribute to understanding of the processes and mechanisms by which lectins participate in insect immunity. This review summarizes existing studies of immune responses stimulated by endogenous or exogenous lectins. Understanding how lectins modulate insect immune responses can provide insight which, in turn, can help to elaborate novel ideas applicable for the protection of beneficial insects and the development of novel pest control strategies.
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Singh, Ram y Amandeep Walia. "Antioxidant and antimicrobial activities of Penicillium sp. lectins". Archives of Biological Sciences 71, n.º 3 (2019): 517–24. http://dx.doi.org/10.2298/abs190529035s.
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Lectins are a diverse group of proteins of non-immune origin that interact specifically with glycans. Owing to their specificity, they can mediate various cellular and molecular recognition processes. To explore information on biological activities of lectins from Penicillium duclauxii, P. proteolyticum and P. griseoroseum, they were investigated for their antioxidant and antimicrobial activities. Penicillium sp. lectins exhibited moderate antioxidant activity. P. duclauxii, P. proteolyticum and P. griseoroseum lectins inhibited DPPH with an IC50 value of 71.42, 75.04 and 82.11 ?g/mL, respectively. P. duclauxii, P. proteolyticum and P. griseoroseum lectins inhibited the hydrogen peroxide radical with IC50 values of 198.57, 209.76 and 215.31 ?g/mL, respectively. P. duclauxii and P. proteolyticum lectins exhibited potent antibacterial activity against Gram-negative bacteria. P. griseoroseum lectin inhibited only Gram-positive bacteria. Penicillium sp. lectins did not exhibit antifungal activity. The biological potential of Penicillium sp. lectins will help to understand their biomedical applications. This is the first report on the antioxidant and antimicrobial activities of purified lectins from Penicillium sp.
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Abdulina, D. R., L. M. Purish y G. O. Iutynska. "Specificity of Lectins Labeled with Colloidal Gold to the Exopolymeric Matrix Carbohydrates of the Sulfate-Reducing Bacteria Biofilm Formed on Steel". Mikrobiolohichnyi Zhurnal 82, n.º 5 (17 de octubre de 2020): 11–20. http://dx.doi.org/10.15407/microbiolj82.05.011.
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The studies of the carbohydrate composition of the sulfate-reducing bacteria (SRB) biofilms formed on the steel surface, which are a factor of microbial corrosion, are significant. Since exopolymers synthesized by bacteria could activate corrosive processes. The aim of the study was to investigate the specificity of commercial lectins, labeled with colloidal gold to carbohydrates in the biofilm exopolymeric matrix produced by the corrosive-relevant SRB strains from man-caused ecotopes. Methods. Microbiological methods (obtaining of the SRB biofilms during cultivation in liquid Postgate B media under microaerophilic conditions), biochemical methods (lectin-binding analysis of 10 commercial lectins, labeled with colloidal gold), transmission electron microscopy using JEM-1400 JEOL. Results. It was shown using transmission electron microscopy that the binding of lectins with carbohydrates in the biofilm of the studied SRB strains occurred directly in the exopolymerіс matrix, as well as on the surfaces of bacterial cells, as seen by the presence of colloidal gold particles. For detection of the neutral carbohydrates (D-glucose and D-mannose) in the biofilm of almost all studied bacterial strains PSA lectin was the most specific. This lectin binding in biofilms of Desulfotomaculum sp. К1/3 and Desulfovibrio sp. 10 strains was higher in 90.8% and 94.4%, respectively, then for ConA lectin. The presence of fucose in the SRB biofilms was detected using LABA lectin, that showed specificity to the biofilm EPS of all the studied strains. LBA lectin was the most specific to N-аcetyl-D-galactosamine for determination of amino sugars in the biofilm. The amount of this lectin binding in D. vulgaris DSM644 biofilm was 30.3, 10.1 and 9.3 times higher than SBA, SNA and PNA lectins, respectively. STA, LVA and WGA lectins were used to detect the N-acetyl-Dglucosamine and sialic acid in the biofilm. WGA lectin showed specificity to N-acetyl-D-glucosamine in the biofilm of all the studied SRB; maximum number of bounded colloidal gold particles (175 particles/μm2) was found in the Desulfotomaculum sp. TC3 biofilm. STA lectin was interacted most actively with N-acetyl-D-glucosamine in Desulfotomaculum sp. TC3 and Desulfomicrobium sp. TC4 biofilms. The number of bounded colloidal gold particles was in 9.2 and 7.4 times higher, respectively, than using LVA lectin. The lowest binding of colloidal gold particles was observed for LVA lectin. Conclusions. It was identified the individual specificity of the 10 commercial lectins to the carbohydrates of biofilm matrix on the steel surface, produced by SRB. It was estimated that lectins with identical carbohydrates specificity had variation in binding to the biofilm carbohydrates of different SRB strains. Establishing of the lectin range selected for each culture lead to the reduction of the scope of studies and labor time in the researching of the peculiarities of exopolymeric matrix composition of biofilms formed by corrosiverelevant SRB.
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Michael Stanley, C. y Thomas E. Phillips. "Sequential staining and de-staining of a single section by a panel of fluorescently-tagged lectins". Proceedings, annual meeting, Electron Microscopy Society of America 53 (13 de agosto de 1995): 1054–55. http://dx.doi.org/10.1017/s0424820100141640.
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Numerous previous studies have used fluorescently tagged lectins to demonstrate the mucin glycoprotein secretory product of intestinal goblet cells are heterogeneous in respect to their lectin binding sites . Lectins stain the mucin secretory product in partially overlapping subpopulations of goblet cells. There are several difficulties in using a panel of fluorescently tagged lectins to determine the overlapping sites of binding. First, steric hindrances resulting from the binding of the first lectin compete with the subsequent binding of other lectins to the same or adjacent sites. Secondly, the number of fluorescent tags that can be practically differentiated by routinely configured microscopes is generally limited to two or three. As an alternative approach, we investigated whether 8 M urea could remove previous bound lectins without damaging the carbohydrate binding sites. Microwave treatment with 8 M urea has previously been used to recover antibody binding sites masked by fixation and embedding.Small pieces of distal colon were removed from anesthetized rats and fixed for 2 hours at room temperature in 2% freshly-depolymerized paraformaldehyde in 70 mM NaCl, 30 mM HEPES, 2 mM CaCl2, pH 7.4.
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Lauc, Gordan, Mirna Flögel y Werner E. G. Müller. "Biotinylated Carbohydrate Markers -A Novel Tool for Lectin Research". Zeitschrift für Naturforschung C 49, n.º 11-12 (1 de diciembre de 1994): 843–48. http://dx.doi.org/10.1515/znc-1994-11-1220.
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One of the key obstacles in lectin research is the lack of specific techniques for their detection. Novel markers, biotin-labeled carbohydrates, could contribute to overcome this problem. Being at least 10 times more sensitive than neoglycoproteins in the membranescreening assays, they also enable direct detection of lectins in complex mixtures. The markers were synthesized by linking biotin to one, and a carbohydrate (galactose or glucose) to the other amino group of (the amino acid) lysine. After synthesis the markers were chromatographically purified on lectin (RCA for galactose marker, ConA for glucose marker) and avidin affinity columns. The applicability of the markers to detect lectins was demonstrated e.g. with sponge extracts (from Geodia cydonium). Following incubation with biotin-labeled carbohydrates covalent cross-linking between lectins and markers was induced by UV radiation. After transfer to the blotting membrane, lectins were detected with deglycosylated antibiotin antibody labeled with alkaline phosphatase. Besides for the cross-linking technique, the biotinylated carbohydrate markers were also used for detection of lectins on the nitrocellulose membrane in gene library screening and slot blotting.
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Krotkiewska, Bozena, Marta Pasek y Hubert Krotkiewski. "Interaction of glycophorin A with lectins as measured by surface plasmon resonance (SPR)." Acta Biochimica Polonica 49, n.º 2 (30 de junio de 2002): 481–90. http://dx.doi.org/10.18388/abp.2002_3807.
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Glycophorin A (GPA), the major sialoglycoprotein of the human erythrocyte membrane, was isolated from erythrocytes of healthy individuals of blood groups A, B and O using phenol-water extraction of erythrocyte membranes. Interaction of individual GPA samples with three lectins (Psathyrella velutina lectin, PVL; Triticum vulgaris lectin, WGA and Sambucus nigra I agglutinin SNA-I) was analyzed using a BIAcore biosensor equipped with a surface plasmon resonance (SPR) detector. The experiments showed no substantial differences in the interaction between native and desialylated GPA samples originating from erythrocytes of either blood group and each of the lectins. Desialylated samples reacted weaker than the native ones with all three lectins. PVL reacted about 50-fold more strongly than WGA which, similar to PVL, recognizes GlcNAc and Neu5Ac residues. SNA-I lectin, recognizing alpha2-6 linked Neu5Ac residues, showed relatively weak reaction with native and only residual reaction with desialylated GPA samples. The data obtained show that SPR is a valuable method to determine interaction of glycoproteins with lectins, which potentially can be used to detect differences in the carbohydrate moiety of individual glycoprotein samples.
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Khan, Farha, Devanshu Kurre y K. Suguna. "Crystal structures of a β-trefoil lectin from Entamoeba histolytica in monomeric and a novel disulfide bond-mediated dimeric forms". Glycobiology 30, n.º 7 (21 de enero de 2020): 474–88. http://dx.doi.org/10.1093/glycob/cwaa001.
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Abstract β-Trefoil lectins are galactose/N-acetyl galactosamine specific lectins, which are widely distributed across all kingdoms of life and are known to perform several important functions. However, there is no report available on the characterization of these lectins from protozoans. We have performed structural and biophysical studies on a β-trefoil lectin from Entamoeba histolytica (EntTref), which exists as a mixture of monomers and dimers in solution. Further, we have determined the affinities of EntTref for rhamnose, galactose and different galactose-linked sugars. We obtained the crystal structure of EntTref in a sugar-free form (EntTref_apo) and a rhamnose-bound form (EntTref_rham). A novel Cys residue-mediated dimerization was revealed in the crystal structure of EntTref_apo while the structure of EntTref_rham provided the structural basis for the recognition of rhamnose by a β-trefoil lectin for the first time. To the best of our knowledge, this is the only report of the structural, functional and biophysical characterization of a β-trefoil lectin from a protozoan source and the first report of Cys-mediated dimerization in this class of lectins.
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Szydlak, Renata, Ingrid H. Øvreeide, Marcin Luty, Tomasz Zieliński, Victorien E. Prot, Joanna Zemła, Bjørn T. Stokke y Małgorzata Lekka. "Bladder Cancer Cells Interaction with Lectin-Coated Surfaces under Static and Flow Conditions". International Journal of Molecular Sciences 24, n.º 9 (4 de mayo de 2023): 8213. http://dx.doi.org/10.3390/ijms24098213.
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Aberrant expression of glycans, i.e., oligosaccharide moiety covalently attached to proteins or lipids, is characteristic of various cancers, including urothelial ones. The binding of lectins to glycans is classified as molecular recognition, which makes lectins a strong tool for understanding their role in developing diseases. Here, we present a quantitative approach to tracing glycan–lectin interactions in cells, from the initial to the steady phase of adhesion. The cell adhesion was measured between urothelial cell lines (non-malignant HCV29 and carcinoma HT1376 and T24 cells) and lectin-coated surfaces. Depending on the timescale, single-cell force spectroscopy, and adhesion assays conducted in static and flow conditions were applied. The obtained results reveal that the adhesion of urothelial cells to two specific lectins, i.e., phytohemagglutinin-L and wheat germ agglutinin, was specific and selective. Thus, these lectins can be applied to selectively capture, identify, and differentiate between cancer types in a label-free manner. These results open up the possibility of designing lectin-based biosensors for diagnostic or prognostic purposes and developing strategies for drug delivery that could target cancer-associated glycans.
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Molodchenkova, O. О., O. V. Ryshchakova, T. V. Kartuzova y L. T. Mishchenko. "Characterization of lectins from wheat seedlings infected with Fusarium graminearum and treated by jasmonic acid". Ukrainian Biochemical Journal 95, n.º 2 (14 de junio de 2023): 83–92. http://dx.doi.org/10.15407/ubj95.02.083.
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Fusarium head blight is one of the most serious diseases of wheat caused by a range of Fusarium fungi, which infects the heads of the crop, reducing grain yield. Lectins that specifically bind carbohydrate ligands of various chemical nature and Jasmonic acid (JA) as a key regulator of plant development play an important role in plant protective responses to biotic factors. The goal of the study was to determine the activity and biochemical characteristics of soluble lectins in wheat seedlings of varieties. ‘Lastivka odeska’ with a high resiliency to Fusarium graminearum and ‘Nikonia odeska’ susceptible to Fusarium graminearum. Wheat seedlings were grown on the media containing pathogenic infection or JA solution. Lectins were purified by affinity chromatography and separated by electrophoresis in 15% PAGE. Lectin activity was determined by the method of trypsinized blood erythrocytes hemagglutination. Molecular mass of the main components of lectins from ‘Lastivka odeska’ seedlings was determined to be 67, 60, 45 kDa, and of the main component of lectins from ‘Nikonia odeska’ seedlings – 45 kDa. Lectins isolated from the control untreated seedlings had preferential affinity for N-acetylglucosamine, D-galactosamine and D-fructose-6-phosphate. It was shown that both at pathogen action or JA treatment lectin activity in the seedlings of resistant ‘Lastivka odeska’ variety was increased while in the seedlings of susceptible ‘Nikonia odeska’ variety it was decreased as compared to control. At the joint action of pathogen and JA lectin activity in the seedlings of susceptible variety increased compared with the infected seedlings. The results obtained can be used for development of biochemical methods for assessing the degree of wheat varieties resiliency to fusariose. Keywords: affinity to carbohydrates, Fusarium graminearum, jasmonic acid, resiliency to fusariose, soluble lectins, wheat variety
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Assreuy, A. M. S., M. D. Shibuya, G. J. Martins, M. L. P. De Souza, B. S. Cavada, R. A. Moreira, J. T. A. Oliveira, R. A. Ribeiro y C. A. Flores. "Anti-inflammatory effect of glucose—mannose binding lectins isolated from Brazilian beans". Mediators of Inflammation 6, n.º 3 (1997): 201–10. http://dx.doi.org/10.1080/09629359791695.
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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 andCanavalia 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 toE. coliendotoxin (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.
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Rachmaninov, Ofra, Keren D. Zinger-Yosovich y Nechama Gilboa-Garber. "Preventing Ralstonia solanacearum adhesion with glycans from cashew, cocoa, coffee, pumpkin, and tomato seed extract". Canadian Journal of Microbiology 58, n.º 7 (julio de 2012): 856–62. http://dx.doi.org/10.1139/w2012-062.
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Ralstonia solanacearum wilts many plants, causing heavy agricultural losses. Its pathogenic strain ATCC 11696 produces 2 hemagglutinating lectins: RSL and RS-IIL. These lectins may bind to terminal l-fucose-, d-arabinose-, and d-mannose-bearing seedling xylem cell wall glycans, thus enabling pathogen adhesion to them, with devastating infection establishment. Blocking the active sites of these lectins with seed embryo-surrounding oligo- and poly-saccharides hampers binding of the lectins to the embryos. The current study shows that seeds of cashew, cocoa, coffee, pumpkin, and tomato contain low and high molecular mass glycans that block RSL and RS-IIL (like its homologous Pseudomonas aeruginosa PA-IIL lectin). The blocking of the pathogen lectins, which is attributable to the documented composition of the oligo- and poly-saccharides of these seeds, is similar to that observed with animal glycoproteins of avian egg whites (protecting their embryos from infections) and of milk and royal jelly, which likewise protect mammal and bee neonates, respectively. RSL was most strongly inhibited by cashew seed glycans, and RS-IIL by coffee seed glycans. Western blot analyses with these lectins instead of antibodies revealed the hitherto undescribed presence of lectin-binding glycoproteins in the coffee, pumpkin, tomato, and cashew (but not cocoa) seeds. The use of these lectins for unveiling potent embryo-protecting seed glycans might be helpful for seedling-bioprotection projects similar to those planned for animal protection against antibiotic-resistant infections.
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Barre, Annick, Els J. M. Van Damme, Mathias Simplicien, Sophie Le Poder, Bernard Klonjkowski, Hervé Benoist, David Peyrade y Pierre Rougé. "Man-Specific Lectins from Plants, Fungi, Algae and Cyanobacteria, as Potential Blockers for SARS-CoV, MERS-CoV and SARS-CoV-2 (COVID-19) Coronaviruses: Biomedical Perspectives". Cells 10, n.º 7 (28 de junio de 2021): 1619. http://dx.doi.org/10.3390/cells10071619.
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Betacoronaviruses, responsible for the “Severe Acute Respiratory Syndrome” (SARS) and the “Middle East Respiratory Syndrome” (MERS), use the spikes protruding from the virion envelope to attach and subsequently infect the host cells. The coronavirus spike (S) proteins contain receptor binding domains (RBD), allowing the specific recognition of either the dipeptidyl peptidase CD23 (MERS-CoV) or the angiotensin-converting enzyme ACE2 (SARS-Cov, SARS-CoV-2) host cell receptors. The heavily glycosylated S protein includes both complex and high-mannose type N-glycans that are well exposed at the surface of the spikes. A detailed analysis of the carbohydrate-binding specificity of mannose-binding lectins from plants, algae, fungi, and bacteria, revealed that, depending on their origin, they preferentially recognize either complex type N-glycans, or high-mannose type N-glycans. Since both complex and high-mannose glycans substantially decorate the S proteins, mannose-specific lectins are potentially useful glycan probes for targeting the SARS-CoV, MERS-CoV, and SARS-CoV-2 virions. Mannose-binding legume lectins, like pea lectin, and monocot mannose-binding lectins, like snowdrop lectin or the algal lectin griffithsin, which specifically recognize complex N-glycans and high-mannose glycans, respectively, are particularly adapted for targeting coronaviruses. The biomedical prospects of targeting coronaviruses with mannose-specific lectins are wide-ranging including detection, immobilization, prevention, and control of coronavirus infection.
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Petrova, Natalia y Natalia Mokshina. "Using FIBexDB for In-Depth Analysis of Flax Lectin Gene Expression in Response to Fusarium oxysporum Infection". Plants 11, n.º 2 (7 de enero de 2022): 163. http://dx.doi.org/10.3390/plants11020163.
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Plant proteins with lectin domains play an essential role in plant immunity modulation, but among a plurality of lectins recruited by plants, only a few members have been functionally characterized. For the analysis of flax lectin gene expression, we used FIBexDB, which includes an efficient algorithm for flax gene expression analysis combining gene clustering and coexpression network analysis. We analyzed the lectin gene expression in various flax tissues, including root tips infected with Fusarium oxysporum. Two pools of lectin genes were revealed: downregulated and upregulated during the infection. Lectins with suppressed gene expression are associated with protein biosynthesis (Calreticulin family), cell wall biosynthesis (galactose-binding lectin family) and cytoskeleton functioning (Malectin family). Among the upregulated lectin genes were those encoding lectins from the Hevein, Nictaba, and GNA families. The main participants from each group are discussed. A list of lectin genes, the expression of which can determine the resistance of flax, is proposed, for example, the genes encoding amaranthins. We demonstrate that FIBexDB is an efficient tool both for the visualization of data, and for searching for the general patterns of lectin genes that may play an essential role in normal plant development and defense.
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Taatjes, D. J., L. A. Barcomb, K. O. Leslie y R. B. Low. "Lectin binding patterns to terminal sugars of rat lung alveolar epithelial cells." Journal of Histochemistry & Cytochemistry 38, n.º 2 (febrero de 1990): 233–44. http://dx.doi.org/10.1177/38.2.1688898.
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We used post-embedding cytochemical techniques to investigate the lectin binding profiles of rat lung alveolar epithelial cells. Sections from rat lung embedded in the hydrophilic resin Lowicryl K4M were incubated either directly with a lectin-gold complex or with an unlabeled lectin followed by a specific glycoprotein-gold complex. The binding patterns of the five lectins used could be divided into three categories according to their reactivity with alveolar epithelial cells: (a) the Limax flavus lectin and Ricinus communis I lectin bound to both type I and type II cell plasma membranes; (b) the Helix pomatia lectin and Sambucus nigra L. lectin bound to type II but not type I cells; and (c) the Erythrina cristagalli lectin reacted with type I cells but was unreactive with type II cells. The specificity of staining was assessed by control experiments, including pre-absorption of the lectins with various oligosaccharides and enzymatic pre-treatment of sections with highly purified glycosidases to remove specific sugar residues. The results demonstrate that these lectins can be used to distinguish between type I and type II cells and would therefore be useful probes for investigating cell dynamics during lung development and remodeling.