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Willy J Peumans - One of the best experts on this subject based on the ideXlab platform.
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leaves of the lamiaceae species glechoma hederacea ground ivy contain a Lectin that is structurally and evolutionary related to the legume Lectins
Plant Journal, 2003Co-Authors: Weifang Wang, Claire Rossi, Willy J Peumans, Paul Proost, Jianping Chen, Pierre Rougé, Els J. M. Van DammeAbstract:Summary A novel Lectin has been isolated and cloned from leaves of Glechoma hederacea (ground ivy), a typical representative of the plant family Lamiaceae. Biochemical analyses indicated that the G. hederacea agglutinin (Gleheda) is a tetrameric protein consisting of four subunits pairwise linked through an interchain disulphide bridge and exhibits a preferential specificity towards N-acetylgalactosamine. Cloning of the corresponding gene and molecular modeling of the deduced sequence demonstrated that Gleheda shares high sequence similarity with the legume Lectins and exhibits the same overall fold and three-dimensional structure as the classical legume Lectins. The identification of a soluble and active legume Lectin ortholog in G. hederacea not only indicates that the yet unclassified Lamiaceae Lectins belong to the same Lectin family as the legume Lectins, but also sheds a new light on the specificity, physiological role and evolution of the classical legume Lectins.
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Cloning and characterization of a monocot mannose-binding Lectin from Crocus vernus (family Iridaceae).
European journal of biochemistry, 2000Co-Authors: Els J. M. Van Damme, Pierre Rougé, Annick Barre, Corinne Houlès Astoul, Willy J PeumansAbstract:The molecular structure and carbohydrate-binding activity of the Lectin from bulbs of spring crocus (Crocus vernus) has been determined unambiguously using a combination of protein analysis and cDNA cloning. Molecular cloning revealed that the Lectin called C. vernus agglutinin (CVA) is encoded by a precursor consisting of two tandemly arrayed Lectin domains with a reasonable sequence similarity to the monocot mannose-binding Lectins. Post-translational cleavage of the precursor yields two equally sized polypeptides. Mature CVA consists of two pairs of polypeptides and hence is a heterotetrameric protein. Surface plasmon resonance studies of the interaction of the crocus Lectin with high mannose-type glycans showed that the Lectin interacts specifically with exposed alpha-1,3-dimannosyl motifs. Molecular modelling studies confirmed further the close relationships in overall fold and three-dimensional structure of the mannose-binding sites of the crocus Lectin and other monocot mannose-binding Lectins. However, docking experiments indicate that only one of the six putative mannose-binding sites of the CVA protomer is active. These results can explain the weak carbohydrate-binding activity and low specific agglutination activity of the Lectin. As the cloning and characterization of the spring crocus Lectin demonstrate that the monocot mannose-binding Lectins occur also within the family Iridaceae a refined model of the molecular evolution of this Lectin family is proposed.
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plant Lectins a composite of several distinct families of structurally and evolutionary related proteins with diverse biological roles
Critical Reviews in Plant Sciences, 1998Co-Authors: Els J. M. Van Damme, Willy J Peumans, Annick Barre, Pierre RougéAbstract:Many plants contain carbohydrate-binding proteins that are commonly designated as Lectins, agglutinins, or hemagglutinins. Due to the obvious differences in molecular structure, biochemical properties, and carbohydrate-binding specificity, plant Lectins are usually considered a complex and heterogeneous group of proteins. Recent advances in the structural analysis of Lectins and molecular cloning of Lectin genes enable subdividision of plant Lectins in a limited number of subgroups of structurally and evolutionary related proteins. Four major Lectin families, namely, the legume Lectins, the chitin-binding Lectins composed of hevein domains, the type 2 ribosome-inactivating proteins, and the monocot mannose-binding Lectins comprise the majority of all currently known plant Lectins. In addition to these four large families the jacalin-related Lectins, the amaranthin family, and the Cucurbitaceae phloem Lectins are now recognized as separate subgroups. Each of the above-mentioned Lectin families is discussed...
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molecular cloning of the bark and seed Lectins from the japanese pagoda tree sophora japonica
Plant Molecular Biology, 1997Co-Authors: E J M Van Damme, Pierre Rougé, Annick Barre, Willy J PeumansAbstract:cDNA clones encoding the bark and seed Lectins from Sophora japonica were isolated and their sequences analyzed. Screening of a cDNA library constructed from polyA RNA isolated from the bark resulted in the isolation of three different Lectin cDNA clones. The first clone encodes the GalNAc-specific bark Lectin which was originally described by Hankins et al. whereas the other clones encode the two isoforms of the mannose/glucose-specific Lectin reported by Ueno et al.. Molecular cloning of the seed Lectin genes revealed that Sophora seeds contain only a GalNAc-specific Lectin which is highly homologous to though not identical with the GalNAc-specific Lectin from the bark. All Lectin polypeptides are translated from mRNAs of ca. 1.3 kb encoding a precursor carrying a signal peptide. In the case of the mannose/glucose-specific bark Lectins this precursor is post-translationally processed in two smaller peptides. Alignment of the deduced amino acid sequences of the different clones revealed striking sequence similarities between the mannose/glucose-binding and the GalNAc-specific Lectins. Furthermore, there was a high degree of sequence homology with other legume Lectins which allowed molecular modelling of the Sophora Lectins using the coordinates of the Pisum sativum, Lathyrus ochrus and Erythrina corallodendron Lectins.
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cloning and characterization of the Lectin cdna clones from onion shallot and leek
Plant Molecular Biology, 1993Co-Authors: E J M Van Damme, Arpad Pusztai, Irwin J. Goldstein, Koen Smeets, I Engelborghs, H Aelbers, Jan Balzarini, F Van Leuven, Willy J PeumansAbstract:Characterization of the Lectins from onion (Allium cepa), shallot (A. ascalonicum) and leek (A. porrum) has shown that these Lectins differ from previously isolated Alliaceae Lectins not only in their molecular structure but also in their ability to inhibit retrovirus infection of target cells. cDNA libraries constructed from poly(A)-rich RNA isolated from young shoots of onion, shallot and leek were screened for Lectin cDNA clones using colony hybridization. Sequence analysis of the Lectin cDNA clones from these three species revealed a high degree of sequence similarity both at the nucleotide and at the amino acid level. Apparently the onion, shallot and leek Lectins are translated from mRNAs of ca. 800 nucleotides. The primary translation products are preproproteins (ca. 19 kDa) which are converted into the mature Lectin polypeptides (12.5-13 kDa) after post-translational modifications. Southern blot analysis of genomic DNA has shown that the Lectins are most probably encoded by a family of closely related genes which is in good agreement with the sequence heterogeneity found between different Lectin cDNA clones of one species.
Els J. M. Van Damme - One of the best experts on this subject based on the ideXlab platform.
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Messages From the Past: New Insights in Plant Lectin Evolution.
Frontiers in Plant Science, 2019Co-Authors: Sofie Van Holle, Els J. M. Van DammeAbstract:Lectins are a large and diverse class of proteins, found in all kingdoms of life. Plants are known to express different types of carbohydrate-binding proteins, each containing at least one particular Lectin domain which enables them to specifically recognize and bind carbohydrate structures. The group of plant Lectins is heterogeneous in terms of structure, biological activity and function. Lectins control various aspects of plant development and defense. Some Lectins facilitate recognition of exogenous danger signals or play a role in endogenous signaling pathways, while others are considered as storage proteins or involved in symbiotic relationships. In this study, we revisit the origin of the different plant Lectin families in view of the recently reshaped tree of life. Due to new genomic sampling of previously unknown microbial lineages, the tree of life has expanded and was reshaped multiple times. In addition, more plant genomes especially from basal Phragmoplastophyta, bryophytes, and Salviniales (e.g., Chara braunii, Marchantia polymorpha, Physcomitrella patens, Azolla filiculoides, and Salvinia cucullata) have been analyzed, and annotated genome sequences have become accessible. We searched 38 plant genome sequences including core eudicots, monocots, gymnosperms, fern, lycophytes, bryophytes, charophytes, chlorophytes, glaucophytes, and rhodophytes for Lectin motifs, performed an extensive comparative analysis of Lectin domain architectures, and determined the phylogenetic and evolutionary history of Lectins in the plant lineage. In conclusion, we describe the conservation of particular domains in plant Lectin sequences obtained from algae to higher plants. The strong conservation of several Lectin motifs highlights their significance for plants.
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History of Plant Lectin Research
Methods of Molecular Biology, 2014Co-Authors: Els J. M. Van DammeAbstract:Numerous plant species are known to express one or more Lectins or proteins containing a Lectin domain, enabling these proteins to select and bind specific carbohydrate structures. The group of plant Lectins is quite heterogeneous since Lectins differ in their molecular structure, specificity for certain carbohydrate structures, and biological activities resulting therefrom. This chapter presents a short historical overview on how plant Lectin research has evolved over the years from a discipline aiming merely at the purification and characterization of plant Lectins towards the application of plant Lectins as tools in glycobiology.
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plant insect interactions what can we learn from plant Lectins
Archives of Insect Biochemistry and Physiology, 2010Co-Authors: Katrien Michiels, Els J. M. Van Damme, Guy SmaggheAbstract:Many plant Lectins have high anti-insect potential. Although the effects of most Lectins are only moderately influencing development or population growth of the insect, some Lectins have strong insecticidal properties. In addition, some studies report a deterrent activity towards feeding and oviposition behavior. Transmission of plant Lectins to the next trophic level has been investigated for several tritrophic interactions. Effects of Lectins with different sugar specificities can vary substantially with the insect species under investigation and with the experimental setup. Lectin binding in the insect is an essential step in exerting a toxic effect. Attempts have been made to study the interactions of Lectins in several insect tissues and to identify Lectin-binding receptors. Ingested Lectins generally bind to parts of the insect gut. Furthermore, some Lectins such as the Galanthus nivalus agglutinin (GNA) cross the gut epithelium into the hemolymph and other tissues. Recently, several candidate Lectin-binding receptors have been isolated from midgut extracts. To date little is known about the exact mechanism for insecticidal activity of plant Lectins. However, insect glycobiology is an emerging research field and the recent technological advances in the analysis of Lectin carbohydrate specificities and insect glycobiology will certainly lead to new insights in the interactions between plant Lectins and insects, and to a better understanding of the molecular mechanisms involved. © 2010 Wiley Periodicals, Inc.
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leaves of the lamiaceae species glechoma hederacea ground ivy contain a Lectin that is structurally and evolutionary related to the legume Lectins
Plant Journal, 2003Co-Authors: Weifang Wang, Claire Rossi, Willy J Peumans, Paul Proost, Jianping Chen, Pierre Rougé, Els J. M. Van DammeAbstract:Summary A novel Lectin has been isolated and cloned from leaves of Glechoma hederacea (ground ivy), a typical representative of the plant family Lamiaceae. Biochemical analyses indicated that the G. hederacea agglutinin (Gleheda) is a tetrameric protein consisting of four subunits pairwise linked through an interchain disulphide bridge and exhibits a preferential specificity towards N-acetylgalactosamine. Cloning of the corresponding gene and molecular modeling of the deduced sequence demonstrated that Gleheda shares high sequence similarity with the legume Lectins and exhibits the same overall fold and three-dimensional structure as the classical legume Lectins. The identification of a soluble and active legume Lectin ortholog in G. hederacea not only indicates that the yet unclassified Lamiaceae Lectins belong to the same Lectin family as the legume Lectins, but also sheds a new light on the specificity, physiological role and evolution of the classical legume Lectins.
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plant Lectins a composite of several distinct families of structurally and evolutionary related proteins with diverse biological roles
Critical Reviews in Plant Sciences, 1998Co-Authors: Els J. M. Van Damme, Willy J Peumans, Annick Barre, Pierre RougéAbstract:Many plants contain carbohydrate-binding proteins that are commonly designated as Lectins, agglutinins, or hemagglutinins. Due to the obvious differences in molecular structure, biochemical properties, and carbohydrate-binding specificity, plant Lectins are usually considered a complex and heterogeneous group of proteins. Recent advances in the structural analysis of Lectins and molecular cloning of Lectin genes enable subdividision of plant Lectins in a limited number of subgroups of structurally and evolutionary related proteins. Four major Lectin families, namely, the legume Lectins, the chitin-binding Lectins composed of hevein domains, the type 2 ribosome-inactivating proteins, and the monocot mannose-binding Lectins comprise the majority of all currently known plant Lectins. In addition to these four large families the jacalin-related Lectins, the amaranthin family, and the Cucurbitaceae phloem Lectins are now recognized as separate subgroups. Each of the above-mentioned Lectin families is discussed...
Daniela Diogenes De Carvalho - One of the best experts on this subject based on the ideXlab platform.
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Caracterização molecular e atividade citotoxica sobre celulas tumorais da Lectina do veneno da serpente Bothrops jararacussu
[s.n.], 2018Co-Authors: Daniela Diogenes De CarvalhoAbstract:Orientador : Jose Camillo NovelloTese (doutorado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: As Lectinas são proteínas ligantes de carboidratos, de origem não-imune, encontradas numa grande variedade de organismos. Aquelas isoladas de venenos de serpentes são constituídas de cadeias polipeptídicas relativas à região molecular correspondente ao domínio de reconhecimento de carboidrato (CRD) de Lectinas. Devido às interações Lectina ¿ carboidrato serem reversíveis, e não covalentes, estas moléculas podem ser utilizadas como importantes ferramentas bioquímicas. Este estudo tem como objetivo: (i) a caracterização da estrutura primária da Lectina do veneno da serpente Bothrops jararacussu (BJcuL); (ii) a investigação do efeito de BJcuL sobre a adesão de células tumorais a proteínas da matriz extracelular, (iii) e sobre a proliferação destas e de células endoteliais. O seqüenciamento N-terminal de BJcuL revelou a presença de uma única seqüência, indicando que esta proteína é composta de cadeias idênticas. A determinação da estrutura primária da Lectina realizada por meio de análise dos peptídeos obtidos pela fragmentação da proteína com c1ostripaína e protease SV-8, demonstrou que BJcuL possui os 18 resíduos invariantes que caracterizam o tipo C de Lectinas animais. Este fato indica que BJcuL pertence à família das Lectinas tipo-C ligantes de I3-galactosídeos e apresenta símilaridades estruturais com a região C-terminal do CRD das Lectinas animais de membrana. Nos primeiros testes em cultura de células tumorais, a viabilidade celular foi avaliada após 5 dias de cultivo na presença da Lectina. Nestas condições, a BJcuL inibiu 50% do crescimento das células de carcinoma de rins ou pâncreas em concentrações entre 1 e 2 mM. Em testes posteriores, foi observado que as células de carcinoma de mama ou de ovário foram capazes de aderir fracamente a BJcuL. Entretanto, esta adesão não inibiu a fixação destas células à proteínas da matriz extracelular tais como; fibronectina, laminina e colágeno tipo I. Após proliferação de linhagens tumorais por 4 dias na presença de BJcuL, foi observado um efeito inibidor dose-dependente da Lectina em células tumorais de glioma e carcinomas de mama ou ovário. No intuito de verificar as propriedades anti angiogênicas da Lectina, foi realizado um ensaio de proliferação de células endoteliais na presença de BJcuL. Os resultados mostraram que a BJcuL, numa concentração de 0,09mM, foi capaz de reduzir em 50% a viabilidade destas células. Os resultados aqui mostrados fornecem base para estudos acerca da estrutura molecular da BJcuL e suas funções, da caracterização da ligação Lectina-carboidrato, e dos mecanismos envolvidos na ligação da Lectina às superficies celularesAbstract: Lectins are carbohydrate-binding proteins of non-immune origin found in a diverse array of organisms. Snake venom Lectins are malleable molecules, and their molecular structure comprises the carbohydrate recognition domain (CRD) characterized in other Ca2+-dependent animal Lectins. They could be used as interesting tools since Lectin-glycan interactions are reversible and non-covalent. The aim of this study was (i) to characterize the molecular structure of Lectin from the venom of the snake Bothrops jararacussu (BJcuL); (ii) to investigate the effect of BJcuL on the adhesion properties of tumor cells to the extracellular matrix proteins, (iii) and on the proliferation of cancer and endothelial cells.The determination of the single N-terminal sequence has shown that BJcuL is a homodimer. The analysis of the complete amino acid sequence of the peptides obtained by enzymatic BJcuL digestion (clostripain and SV-8 protease) showed that this Lectin displays 18 invariant amino acid residues characteristics of C-type Lectins. This fact implies that BJcuL possesses structural similarities to the C-terminal region of the animal membrane Lectins CRD, belonging to the C-type j3-galactoside binding Lectin family. In the first evaluation in a tumor cell system, cell viability was evaluated after 5 days cultivation. This Lectin was a potent inhibitor of growth in human renal or carcinoma cells, with 50% inhibitory concentrations (lC50) of cell growth between 1 and 2 mM of BJcuL. In the second evaluation, cells of human metastatic breast cancer or human ovarian carcinoma cell lines weakly adhere to BJcuL. However, BJcuL was not capable of inhibiting adhesion of these cells to the extracellular matrix proteins such as fibronectin, laminin and type I collagen. 1t was also observed a dose-dependent inhibitory effect of BJcuL in proliferation assays with glioma, breast or ovarian carcinoma cells after 4 days of incubation. Proliferation assays were performed on bovine brain and endothelial cells in order to verify the antiangiogenic properties of the BJcuL These experiments revealed that BJcuL was capable to reduce cell proliferation (lC5o of 0,09mM). Taken together, our findings could be helpful to further studies regarding the Lectin structure and function, Lectin-glycan binding characterization, as well as, the mechanisms involved in BJcuL binding to cell surface molecules, which influence cell proliferation and angiogenesisDoutoradoBioquimicaDoutor em Biologia Funcional e Molecula
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Caracterização molecular e atividade citotoxica sobre celulas tumorais da Lectina do veneno da serpente Bothrops jararacussu
Universidade Estadual de Campinas. Instituto de Biologia, 2002Co-Authors: Daniela Diogenes De CarvalhoAbstract:As Lectinas são proteínas ligantes de carboidratos, de origem não-imune, encontradas numa grande variedade de organismos. Aquelas isoladas de venenos de serpentes são constituídas de cadeias polipeptídicas relativas à região molecular correspondente ao domínio de reconhecimento de carboidrato (CRD) de Lectinas. Devido às interações Lectina ? carboidrato serem reversíveis, e não covalentes, estas moléculas podem ser utilizadas como importantes ferramentas bioquímicas. Este estudo tem como objetivo: (i) a caracterização da estrutura primária da Lectina do veneno da serpente Bothrops jararacussu (BJcuL); (ii) a investigação do efeito de BJcuL sobre a adesão de células tumorais a proteínas da matriz extracelular, (iii) e sobre a proliferação destas e de células endoteliais. O seqüenciamento N-terminal de BJcuL revelou a presença de uma única seqüência, indicando que esta proteína é composta de cadeias idênticas. A determinação da estrutura primária da Lectina realizada por meio de análise dos peptídeos obtidos pela fragmentação da proteína com c1ostripaína e protease SV-8, demonstrou que BJcuL possui os 18 resíduos invariantes que caracterizam o tipo C de Lectinas animais. Este fato indica que BJcuL pertence à família das Lectinas tipo-C ligantes de I3-galactosídeos e apresenta símilaridades estruturais com a região C-terminal do CRD das Lectinas animais de membrana. Nos primeiros testes em cultura de células tumorais, a viabilidade celular foi avaliada após 5 dias de cultivo na presença da Lectina. Nestas condições, a BJcuL inibiu 50% do crescimento das células de carcinoma de rins ou pâncreas em concentrações entre 1 e 2 mM. Em testes posteriores, foi observado que as células de carcinoma de mama ou de ovário foram capazes de aderir fracamente a BJcuL. Entretanto, esta adesão não inibiu a fixação destas células à proteínas da matriz extracelular tais como; fibronectina, laminina e colágeno tipo I. Após proliferação de linhagens tumorais por 4 dias na presença de BJcuL, foi observado um efeito inibidor dose-dependente da Lectina em células tumorais de glioma e carcinomas de mama ou ovário. No intuito de verificar as propriedades anti angiogênicas da Lectina, foi realizado um ensaio de proliferação de células endoteliais na presença de BJcuL. Os resultados mostraram que a BJcuL, numa concentração de 0,09mM, foi capaz de reduzir em 50% a viabilidade destas células. Os resultados aqui mostrados fornecem base para estudos acerca da estrutura molecular da BJcuL e suas funções, da caracterização da ligação Lectina-carboidrato, e dos mecanismos envolvidos na ligação da Lectina às superficies celularesLectins are carbohydrate-binding proteins of non-immune origin found in a diverse array of organisms. Snake venom Lectins are malleable molecules, and their molecular structure comprises the carbohydrate recognition domain (CRD) characterized in other Ca2+-dependent animal Lectins. They could be used as interesting tools since Lectin-glycan interactions are reversible and non-covalent. The aim of this study was (i) to characterize the molecular structure of Lectin from the venom of the snake Bothrops jararacussu (BJcuL); (ii) to investigate the effect of BJcuL on the adhesion properties of tumor cells to the extracellular matrix proteins, (iii) and on the proliferation of cancer and endothelial cells.The determination of the single N-terminal sequence has shown that BJcuL is a homodimer. The analysis of the complete amino acid sequence of the peptides obtained by enzymatic BJcuL digestion (clostripain and SV-8 protease) showed that this Lectin displays 18 invariant amino acid residues characteristics of C-type Lectins. This fact implies that BJcuL possesses structural similarities to the C-terminal region of the animal membrane Lectins CRD, belonging to the C-type j3-galactoside binding Lectin family. In the first evaluation in a tumor cell system, cell viability was evaluated after 5 days cultivation. This Lectin was a potent inhibitor of growth in human renal or carcinoma cells, with 50% inhibitory concentrations (lC50) of cell growth between 1 and 2 mM of BJcuL. In the second evaluation, cells of human metastatic breast cancer or human ovarian carcinoma cell lines weakly adhere to BJcuL. However, BJcuL was not capable of inhibiting adhesion of these cells to the extracellular matrix proteins such as fibronectin, laminin and type I collagen. 1t was also observed a dose-dependent inhibitory effect of BJcuL in proliferation assays with glioma, breast or ovarian carcinoma cells after 4 days of incubation. Proliferation assays were performed on bovine brain and endothelial cells in order to verify the antiangiogenic properties of the BJcuL These experiments revealed that BJcuL was capable to reduce cell proliferation (lC5o of 0,09mM). Taken together, our findings could be helpful to further studies regarding the Lectin structure and function, Lectin-glycan binding characterization, as well as, the mechanisms involved in BJcuL binding to cell surface molecules, which influence cell proliferation and angiogenesi
Pierre Rougé - One of the best experts on this subject based on the ideXlab platform.
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leaves of the lamiaceae species glechoma hederacea ground ivy contain a Lectin that is structurally and evolutionary related to the legume Lectins
Plant Journal, 2003Co-Authors: Weifang Wang, Claire Rossi, Willy J Peumans, Paul Proost, Jianping Chen, Pierre Rougé, Els J. M. Van DammeAbstract:Summary A novel Lectin has been isolated and cloned from leaves of Glechoma hederacea (ground ivy), a typical representative of the plant family Lamiaceae. Biochemical analyses indicated that the G. hederacea agglutinin (Gleheda) is a tetrameric protein consisting of four subunits pairwise linked through an interchain disulphide bridge and exhibits a preferential specificity towards N-acetylgalactosamine. Cloning of the corresponding gene and molecular modeling of the deduced sequence demonstrated that Gleheda shares high sequence similarity with the legume Lectins and exhibits the same overall fold and three-dimensional structure as the classical legume Lectins. The identification of a soluble and active legume Lectin ortholog in G. hederacea not only indicates that the yet unclassified Lamiaceae Lectins belong to the same Lectin family as the legume Lectins, but also sheds a new light on the specificity, physiological role and evolution of the classical legume Lectins.
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Cloning and characterization of a monocot mannose-binding Lectin from Crocus vernus (family Iridaceae).
European journal of biochemistry, 2000Co-Authors: Els J. M. Van Damme, Pierre Rougé, Annick Barre, Corinne Houlès Astoul, Willy J PeumansAbstract:The molecular structure and carbohydrate-binding activity of the Lectin from bulbs of spring crocus (Crocus vernus) has been determined unambiguously using a combination of protein analysis and cDNA cloning. Molecular cloning revealed that the Lectin called C. vernus agglutinin (CVA) is encoded by a precursor consisting of two tandemly arrayed Lectin domains with a reasonable sequence similarity to the monocot mannose-binding Lectins. Post-translational cleavage of the precursor yields two equally sized polypeptides. Mature CVA consists of two pairs of polypeptides and hence is a heterotetrameric protein. Surface plasmon resonance studies of the interaction of the crocus Lectin with high mannose-type glycans showed that the Lectin interacts specifically with exposed alpha-1,3-dimannosyl motifs. Molecular modelling studies confirmed further the close relationships in overall fold and three-dimensional structure of the mannose-binding sites of the crocus Lectin and other monocot mannose-binding Lectins. However, docking experiments indicate that only one of the six putative mannose-binding sites of the CVA protomer is active. These results can explain the weak carbohydrate-binding activity and low specific agglutination activity of the Lectin. As the cloning and characterization of the spring crocus Lectin demonstrate that the monocot mannose-binding Lectins occur also within the family Iridaceae a refined model of the molecular evolution of this Lectin family is proposed.
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plant Lectins a composite of several distinct families of structurally and evolutionary related proteins with diverse biological roles
Critical Reviews in Plant Sciences, 1998Co-Authors: Els J. M. Van Damme, Willy J Peumans, Annick Barre, Pierre RougéAbstract:Many plants contain carbohydrate-binding proteins that are commonly designated as Lectins, agglutinins, or hemagglutinins. Due to the obvious differences in molecular structure, biochemical properties, and carbohydrate-binding specificity, plant Lectins are usually considered a complex and heterogeneous group of proteins. Recent advances in the structural analysis of Lectins and molecular cloning of Lectin genes enable subdividision of plant Lectins in a limited number of subgroups of structurally and evolutionary related proteins. Four major Lectin families, namely, the legume Lectins, the chitin-binding Lectins composed of hevein domains, the type 2 ribosome-inactivating proteins, and the monocot mannose-binding Lectins comprise the majority of all currently known plant Lectins. In addition to these four large families the jacalin-related Lectins, the amaranthin family, and the Cucurbitaceae phloem Lectins are now recognized as separate subgroups. Each of the above-mentioned Lectin families is discussed...
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molecular cloning of the bark and seed Lectins from the japanese pagoda tree sophora japonica
Plant Molecular Biology, 1997Co-Authors: E J M Van Damme, Pierre Rougé, Annick Barre, Willy J PeumansAbstract:cDNA clones encoding the bark and seed Lectins from Sophora japonica were isolated and their sequences analyzed. Screening of a cDNA library constructed from polyA RNA isolated from the bark resulted in the isolation of three different Lectin cDNA clones. The first clone encodes the GalNAc-specific bark Lectin which was originally described by Hankins et al. whereas the other clones encode the two isoforms of the mannose/glucose-specific Lectin reported by Ueno et al.. Molecular cloning of the seed Lectin genes revealed that Sophora seeds contain only a GalNAc-specific Lectin which is highly homologous to though not identical with the GalNAc-specific Lectin from the bark. All Lectin polypeptides are translated from mRNAs of ca. 1.3 kb encoding a precursor carrying a signal peptide. In the case of the mannose/glucose-specific bark Lectins this precursor is post-translationally processed in two smaller peptides. Alignment of the deduced amino acid sequences of the different clones revealed striking sequence similarities between the mannose/glucose-binding and the GalNAc-specific Lectins. Furthermore, there was a high degree of sequence homology with other legume Lectins which allowed molecular modelling of the Sophora Lectins using the coordinates of the Pisum sativum, Lathyrus ochrus and Erythrina corallodendron Lectins.
V. Pospelova - One of the best experts on this subject based on the ideXlab platform.
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Probiotic Lactobacillus and Bifidobacterial Lectins Against Candida albicans and Staphylococcus aureus Clinical Strains: New Class of the Pathogen Biofilm Destructors
Probiotics and Antimicrobial Proteins, 2010Co-Authors: M. Lakhtin, V. Alyoshkin, V. Lakhtin, S. Afanasyev, L. Pozhalostina, V. PospelovaAbstract:Preparations of probiotic bifidobacterial and lactobacillus Lectins possessed system affinity to mannan and mucin-type polymers. It was shown that these Lectins possess fungistatic and fungicidal activities against nystatin-resistant Candida albicans clinical strains. Lectins revealed destructive properties with respect to C. albicans and Staphylococcus aureus biofilms, depending on clinical strain origin and Lectin preparation type. Synergistic antipathogen activities between Lectins and between Lectins and nystatin were observed. In the presence of Lectins, pathogen biofilm degradation occurred in sequential steps, including biofilm refinement, appearance of edge cavities, segmentation, detachment of fragments and their lysis. Fungal response to Lectins was more complex compared to that of staphylococci. Cold stress improved pictures of Lectin antipathogen action. The data indicate that probiotic bacterial Lectins are members of a new class of antimicrobials—destructors of pathogen biofilms.
