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Célia R. Carlini - One of the best experts on this subject based on the ideXlab platform.

  • antifungal properties of Canavalia ensiformis urease and derived peptides
    Peptides, 2012
    Co-Authors: Melissa Postal, Valdirene Moreira Gomes, Anne H S Martinelli, Arlete Beatriz Beckerritt, Rodrigo Ligabuebraun, Diogo Ribeiro Demartini, Suzanna F F Ribeiro, Giancarlo Pasquali, Célia R. Carlini
    Abstract:

    Abstract Ureases (EC 3.5.1.5) are metalloenzymes that hydrolyze urea into ammonia and CO 2 . These proteins have insecticidal and fungicidal effects not related to their enzymatic activity. The insecticidal activity of urease is mostly dependent on the release of internal peptides after hydrolysis by insect digestive cathepsins. Jaburetox is a recombinant version of one of these peptides, expressed in Escherichia coli . The antifungal activity of ureases in filamentous fungi occurs at submicromolar doses, with damage to the cell membranes. Here we evaluated the toxic effect of Canavalia ensiformis urease (JBU) on different yeast species and carried out studies aiming to identify antifungal domain(s) of JBU. Data showed that toxicity of JBU varied according to the genus and species of yeasts, causing inhibition of proliferation, induction of morphological alterations with formation of pseudohyphae, changes in the transport of H + and carbohydrate metabolism, and permeabilization of membranes, which eventually lead to cell death. Hydrolysis of JBU with papain resulted in fungitoxic peptides (∼10 kDa), which analyzed by mass spectrometry, revealed the presence of a fragment containing the N-terminal sequence of the entomotoxic peptide Jaburetox. Tests with Jaburetox on yeasts and filamentous fungi indicated a fungitoxic activity similar to ureases. Plant ureases, such as JBU, and its derived peptides, may represent a new alternative to control medically important mycoses as well as phytopathogenic fungi, especially considering their potent activity in the range of 10 −6 –10 −7  M.

  • characterization of jbure iib isoform of Canavalia ensiformis l dc urease
    Biochimica et Biophysica Acta, 2011
    Co-Authors: Fernanda Mulinari, Célia R. Carlini, Arlete Beatriz Beckerritt, Rodrigo Ligabuebraun, Diogo Ribeiro Demartini, Fernanda Staniscuaski, Hugo Verli, Rodrigo R Fragoso, Evelyn Koeche Schroeder, Maria Fatima Grossidesa
    Abstract:

    Abstract Ureases, nickel-dependent enzymes that catalyze the hydrolysis of urea into ammonia and bicarbonate, are widespread in plants, bacteria, and fungi. Previously, we cloned a cDNA encoding a Canavalia ensiformis urease isoform named JBURE-II, corresponding to a putative smaller urease protein (78 kDa) when compared to other plant ureases. Aiming to produce the recombinant protein, we obtained jbure - IIb , with different 3′ and 5′ ends, encoding a 90 kDa urease. Three peptides unique to the JBURE-II/-IIb protein were detected by mass spectrometry in seed extracts, indicating that jbure - II /- IIb is a functional gene. Comparative modeling indicates that JBURE-IIb urease has an overall shape almost identical to C . ensiformis major urease JBURE-I with all residues critical for urease activity. The cDNA was cloned into the pET101 vector and the recombinant protein was produced in Escherichia coli . The JBURE-IIb protein, although enzymatically inactive presumably due to the absence of Ni atoms in its active site, impaired the growth of a phytopathogenic fungus and showed entomotoxic properties, inhibiting diuresis of Rhodnius prolixus isolated Malpighian tubules, in concentrations similar to those reported for JBURE-I and canatoxin. The antifungal and entomotoxic properties of the recombinant JBURE-IIb apourease are consistent with a protective role of ureases in plants.

  • The toxicity of jack bean [Canavalia ensiformis (L.) DC.] canatoxin to plant pathogenic fungi
    Revista Brasileira de Biologia, 1999
    Co-Authors: Antônia E. A. Oliveira, Kátia Valevski Sales Fernandes, Valdirene Moreira Gomes, Maurício P. Sales, Célia R. Carlini, José Xavier-filho
    Abstract:

    Protein fractions obtained from seeds of the jack bean (Canavalia ensiformis) as well as the amino acid canavanine, present in these seeds, were tested for their capacity to inhibit the growth of the phytopathogenic fungi Macrophomina phaseolina, Colletotrichum gloesporioides, Sclerotium rolfsii and Fusarium oxysporum. We found that most of the proteins examined and also canavanine did not have any effect on the growth of these fungi. On the other hand the toxic protein canatoxin was found to be effective, at a concentration of 2%, in the inhibition of the growth of M. phaseolina, C. gloesporioides and S. rolfsii.

  • The presence of concanavalin A and canatoxin in Canavalia ensiformis DC tissue culture
    Plant cell reports, 1993
    Co-Authors: Alice Sato, Célia R. Carlini, Grace B. S. Barcellos, Eduardo Corrêa Riedel, José Augusto Carneiro, Maria Apparecida Esquibel
    Abstract:

    Isolated embryos, cotyledons and embryos plusa fragment of cotyledon from seeds of Canavalia ensiformis (jack bean) were cultured in vitro. Concanavalin A and canatoxin cross-reactive material were detected by double immunodiffusion tests. Canatoxin was detectable until 30 days in cultures of embryos, embryos plus cotyledons and hypocotyls. Concanavalin A was also present in all cultures being detected until 90 days in cultures treated with 6-benzylaminopurine. No concanavalin A was detected in root cultures. Concanavalin A was present in cell suspensions until 45 days of culture; the culture medium contained neither concanavalin A nor canatoxin. Tissue cultures thus can produce Con A and CNTX and will be an important research tool for studying the biosynthesis of such substances.

  • Lipoxygenase-mediated secretory effect of canatoxin the toxic protein from Canavalia ensiformis seeds.
    Toxicon : official journal of the International Society on Toxinology, 1991
    Co-Authors: Christina Barja-fidalgo, Jorge Almeida Guimaraes, Célia R. Carlini
    Abstract:

    Abstract C. Barja-Fidalgo , J. A. Guimaraes , and C. R. Carlini . Lipoxygenase-mediated secretory effect of canatoxin the toxic protein from Canavalia ensiformis seeds. Toxicon29, 453–459, 1991.—Canatoxin was shown to induce serotonin release from rabbit platelets and rat brain synaptosomes, as well as to release insulin from isolated pancreatic islets. All these effects were dose-dependent and were inhibited by lipoxygenase inhibitors, such as nordihydroguaiaretic acid and esculetin, but not by indomethacin, a cyclo-oxygenase inhibitor. The data suggest that canatoxin-induced secretory effect results from the activation of the lipoxygenase pathway which would elicit exocytosis. Thus, canatoxin might be a useful tool for the study of biological events that involve lipoxygenase mediation.

José Xavier-filho - One of the best experts on this subject based on the ideXlab platform.

  • Insulin-binding canavalin is present in Canavalia ensiformis seed coat.
    Protein and Peptide Letters, 2009
    Co-Authors: Elane Da Silva Ribeiro, Adriana F. Uchoa, Leonardo Gomes Da Silva, Daniela Gois Beghini, André Teixeira Da Silva Ferreira, Jonas Perales, Tania Jacinto, Kátia Valevski Sales Fernandes, José Xavier-filho, Antônia E. A. Oliveira
    Abstract:

    An insulin-binding protein was isolated from Canavalia ensiformis seed coat, by using an insulin-Sepharose 4B affinity chromatography, and the protein was identified as canavalin (Canavalia 7S globulin) by mass spectrometry analysis. The major novelty of these data is the acidic nature of this globulin insulin-binding, in contrast to the basic Bg-like insulin- binding proteins so far reported in plants.

  • Insulin Accelerates Seedling Growth of Canavalia ensiformis (Jack bean)
    Plant Growth Regulation, 2004
    Co-Authors: Antônia E. A. Oliveira, Elane Da Silva Ribeiro, Kátia Valevski Sales Fernandes, Maura Da Cunha, Valdirene Moreira Gomes, José Xavier-filho
    Abstract:

    Insulin is a 6 kDa peptide hormone that activates several metabolic processes and cellular growth. Germination studies showed that insulin, vanadyl sulphate (an insulin mimetic compound), tyrphostin (an inhibitor of insulin receptor kinase activity), pinitol (a chiro inositol analogue) and glucose were able to accelerate Canavalia ensiformis (Jack bean) seedling radicle and epicotyl development. Immunofluorescence microscopy analysis showed that proteins binding to insulin, insulin receptor and phosphoserine antibodies are localized in an internal layer of the C. ensiformis seed coat. These results and others previously reported from our laboratory suggest that insulin, insulin receptor and phosphoserine proteins could be components of signalling pathways akin to those present in animals.

  • The toxicity of jack bean [Canavalia ensiformis (L.) DC.] canatoxin to plant pathogenic fungi
    Revista Brasileira de Biologia, 1999
    Co-Authors: Antônia E. A. Oliveira, Kátia Valevski Sales Fernandes, Valdirene Moreira Gomes, Maurício P. Sales, Célia R. Carlini, José Xavier-filho
    Abstract:

    Protein fractions obtained from seeds of the jack bean (Canavalia ensiformis) as well as the amino acid canavanine, present in these seeds, were tested for their capacity to inhibit the growth of the phytopathogenic fungi Macrophomina phaseolina, Colletotrichum gloesporioides, Sclerotium rolfsii and Fusarium oxysporum. We found that most of the proteins examined and also canavanine did not have any effect on the growth of these fungi. On the other hand the toxic protein canatoxin was found to be effective, at a concentration of 2%, in the inhibition of the growth of M. phaseolina, C. gloesporioides and S. rolfsii.

  • The toxicity of Jack bean (Canavalia ensiformis) cotyledon and seed coat proteins to the cowpea weevil (Callosobruchus maculatus)
    Entomologia Experimentalis et Applicata, 1999
    Co-Authors: Antônia E. A. Oliveira, Kátia Valevski Sales Fernandes, Maurício P. Sales, Olga Lima Tavares Machado, José Xavier-filho
    Abstract:

    The seeds of the Jack bean, Canavalia ensiformis (L) DC are known to contain several toxic substances that prevent their utilisation as food for humans and animals. The lectin concanavalin A and the enzyme urease are the best known of these proteins. We have found that many proteins present in the seeds of the Jack bean, like trypsin inhibitors and canatoxin, are detrimental to the development of the bruchid insect Callosobruchus maculatus (F) (Coleoptera: Bruchidae). Among these proteins, canavalin (vicilin, 7S globulin) was found to be expressed in the seed coat. We suggest that seed coat canavalin, in addition to other detrimental proteins expressed in this tissue, may have been of importance in the evolutionary discrimination of the seeds of this legume by non-pest bruchids.

Adil Denizli - One of the best experts on this subject based on the ideXlab platform.

  • Mannose‐specific lectin isolation from Canavalia ensiformis seeds by PHEMA‐based cryogel
    Biotechnology progress, 2012
    Co-Authors: Isik Percin, Handan Yavuz, Erol Aksoz, Adil Denizli
    Abstract:

    Mannose-specific lectin Concanavalin A (Con A) was purified from Canavalia ensiformis seeds. For this purpose, mannose attached poly(hydroxyethyl methacrylate) (PHEMA) cryogel was prepared by cryopolymerization. Mannose was used as the affinity ligand and was covalently attached onto the PHEMA cryogel via carbodiimide activation. The PHEMA cryogel containing 23.3 mmol mannose/g polymer were used in the binding studies. Con A binding with the mannose attached PHEMA cryogel from Con A aqueous solution was 5.2 mg/g at pH 7. Maximum binding capacity for Con A from C. ensiformis seed extract was 39 mg/g. Con A was eluted with 0.3 M galactose, and the purity of Con A was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. It was observed that the mannose attached PHEMA cryogel can be used without significant decrease in Con A binding capacity after six binding-elution cycles. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012

  • mannose specific lectin isolation from Canavalia ensiformis seeds by phema based cryogel
    Biotechnology Progress, 2012
    Co-Authors: Isik Percin, Handan Yavuz, Erol Aksoz, Adil Denizli
    Abstract:

    Mannose-specific lectin Concanavalin A (Con A) was purified from Canavalia ensiformis seeds. For this purpose, mannose attached poly(hydroxyethyl methacrylate) (PHEMA) cryogel was prepared by cryopolymerization. Mannose was used as the affinity ligand and was covalently attached onto the PHEMA cryogel via carbodiimide activation. The PHEMA cryogel containing 23.3 mmol mannose/g polymer were used in the binding studies. Con A binding with the mannose attached PHEMA cryogel from Con A aqueous solution was 5.2 mg/g at pH 7. Maximum binding capacity for Con A from C. ensiformis seed extract was 39 mg/g. Con A was eluted with 0.3 M galactose, and the purity of Con A was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. It was observed that the mannose attached PHEMA cryogel can be used without significant decrease in Con A binding capacity after six binding-elution cycles. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012

Antônia E. A. Oliveira - One of the best experts on this subject based on the ideXlab platform.

  • Insulin-binding canavalin is present in Canavalia ensiformis seed coat.
    Protein and Peptide Letters, 2009
    Co-Authors: Elane Da Silva Ribeiro, Adriana F. Uchoa, Leonardo Gomes Da Silva, Daniela Gois Beghini, André Teixeira Da Silva Ferreira, Jonas Perales, Tania Jacinto, Kátia Valevski Sales Fernandes, José Xavier-filho, Antônia E. A. Oliveira
    Abstract:

    An insulin-binding protein was isolated from Canavalia ensiformis seed coat, by using an insulin-Sepharose 4B affinity chromatography, and the protein was identified as canavalin (Canavalia 7S globulin) by mass spectrometry analysis. The major novelty of these data is the acidic nature of this globulin insulin-binding, in contrast to the basic Bg-like insulin- binding proteins so far reported in plants.

  • Insulin Accelerates Seedling Growth of Canavalia ensiformis (Jack bean)
    Plant Growth Regulation, 2004
    Co-Authors: Antônia E. A. Oliveira, Elane Da Silva Ribeiro, Kátia Valevski Sales Fernandes, Maura Da Cunha, Valdirene Moreira Gomes, José Xavier-filho
    Abstract:

    Insulin is a 6 kDa peptide hormone that activates several metabolic processes and cellular growth. Germination studies showed that insulin, vanadyl sulphate (an insulin mimetic compound), tyrphostin (an inhibitor of insulin receptor kinase activity), pinitol (a chiro inositol analogue) and glucose were able to accelerate Canavalia ensiformis (Jack bean) seedling radicle and epicotyl development. Immunofluorescence microscopy analysis showed that proteins binding to insulin, insulin receptor and phosphoserine antibodies are localized in an internal layer of the C. ensiformis seed coat. These results and others previously reported from our laboratory suggest that insulin, insulin receptor and phosphoserine proteins could be components of signalling pathways akin to those present in animals.

  • The toxicity of jack bean [Canavalia ensiformis (L.) DC.] canatoxin to plant pathogenic fungi
    Revista Brasileira de Biologia, 1999
    Co-Authors: Antônia E. A. Oliveira, Kátia Valevski Sales Fernandes, Valdirene Moreira Gomes, Maurício P. Sales, Célia R. Carlini, José Xavier-filho
    Abstract:

    Protein fractions obtained from seeds of the jack bean (Canavalia ensiformis) as well as the amino acid canavanine, present in these seeds, were tested for their capacity to inhibit the growth of the phytopathogenic fungi Macrophomina phaseolina, Colletotrichum gloesporioides, Sclerotium rolfsii and Fusarium oxysporum. We found that most of the proteins examined and also canavanine did not have any effect on the growth of these fungi. On the other hand the toxic protein canatoxin was found to be effective, at a concentration of 2%, in the inhibition of the growth of M. phaseolina, C. gloesporioides and S. rolfsii.

  • The toxicity of Jack bean (Canavalia ensiformis) cotyledon and seed coat proteins to the cowpea weevil (Callosobruchus maculatus)
    Entomologia Experimentalis et Applicata, 1999
    Co-Authors: Antônia E. A. Oliveira, Kátia Valevski Sales Fernandes, Maurício P. Sales, Olga Lima Tavares Machado, José Xavier-filho
    Abstract:

    The seeds of the Jack bean, Canavalia ensiformis (L) DC are known to contain several toxic substances that prevent their utilisation as food for humans and animals. The lectin concanavalin A and the enzyme urease are the best known of these proteins. We have found that many proteins present in the seeds of the Jack bean, like trypsin inhibitors and canatoxin, are detrimental to the development of the bruchid insect Callosobruchus maculatus (F) (Coleoptera: Bruchidae). Among these proteins, canavalin (vicilin, 7S globulin) was found to be expressed in the seed coat. We suggest that seed coat canavalin, in addition to other detrimental proteins expressed in this tissue, may have been of importance in the evolutionary discrimination of the seeds of this legume by non-pest bruchids.

Juan F. Ramirez Pedroso - One of the best experts on this subject based on the ideXlab platform.

  • Caracterización fenotípica de aislados de rizobios procedentes de la leguminosa forrajera Canavalia ensiformis
    2012
    Co-Authors: Ionel Hernández Forte, Guianeya Pérez Hernández, Roberto Baños Gordillo, María C. Nápoles García, Pedro R. Rosales Jenqui, Juan F. Ramirez Pedroso
    Abstract:

    Resumen es: El objetivo del presente trabajo fue caracterizar fenotipicamente aislados de rizobios procedentes de la leguminosa forrajera Canavalia ensiformis. Se ca...

  • SELECCIÓN DE AISLADOS DE RIZOBIOS PROVENIENTES DE NÓDULOS DE LA LEGUMINOSA FORRAJERA Canavalia ensiformis Selection of rhizobia isolates from forage legume's nodules Canavalia ensiformis
    2012
    Co-Authors: Ionel Hernández Forte, Guianeya Pérez Hernández, Pedro R. Rosales Genqui, Roberto Baños Gordillo, Juan F. Ramirez Pedroso
    Abstract:

    The objective of this work was to carry out a selection of rhizobia isolates from forage legumes nodules Canavalia ensiformis according to their characteristics and potentialities to develop nitrogen-uxing root nodules in Macroptilium atropurpureum (siratro), as model plant, so that they can constitute promissory strains for biofertilizer elaboration that improve the establishment of the Canavalia in the cattle floors. Twelve rhizobia isolates and two commercial strains, BR 2001 and BR 2003a were used. The possible taxonomic distribution of the isolates was determinated throught the study of their morpho-cultural and physiological characteristics. In vitro nodulation assays were also performed in Macroptilium atropurpureum (siratro). Five possible members of the genera Rhizobium /Sinorhizobium and seven possible members of genera Bradyrhizobium were identified. Although the plants inoculated with the commercial strain BR 2003a presented a bigger number of total nodules and total effective nodules, the plants inoculated with the isolate CP5 presented a bigger number of nodules in the main root and those inoculated with CP12 had a bigger number of effective nodules in this root. The carried out study demonstrates that isolates of autochthonous rizobia as CP5 and CP12 they could constitute promissory strains for the biofertilizer elaboration that improves the establishment of the cultivation of Canavalia in the cattle floors.

  • CARACTERIZACIÓN FENOTÍPICA DE AISLADOS DE RIZOBIOS PROCEDENTES DE LA LEGUMINOSA FORRAJERA Canavalia ensiformis Phenotypical characterization of rhizobia isolates from forage legume Canavalia ensiformis Ionel Hernández Forte , María C. Nápoles García,
    2012
    Co-Authors: Guianeya Pérez Hernández, Roberto Baños Gordillo, Pedro R. Rosales Jenqui, Juan F. Ramirez Pedroso
    Abstract:

    The objective of this work was to characterize phenotypically rhizobia isolates from forage legume Canavalia ensiformis. Twelve isolates (five possible members of the Rhizobium genus, seven possible members of Bradyrhizobium genus) and two commercial strains, BR 2001 and BR 2003a were characterized. For the phenotypic characterization of the bacterial isolates, their capacity to use six carbohydrates as carbon source, their tolerance to acid condition and different levels of NaCl, and the resistence to six antibiotic, were studied; as well as their growing in three incubation temperatures. In addition, the capacity of these isolates to produce polyhidroxibutirates (PHB) was determinated. All rhizobia isolates used lactose, glucose and mannitol as carbon source. One rapid growing isolate was the most tolerant to pH 4.5. The isolates possible members of the Rhizobium/Sinorhizobium genus were more tolerant to NaCl than the isolates possible members of Bradyrhizobium genus. Three of the rapid growing isolates were resistent to six antibiotics. When the isolates were incubated at 37 0 C, all of them except the CP3 isolate and one commercial strain, BR 2001, grown similar to control. The CP10 slow growing isolate had the capacity to produce the biggest PHB concentration (0.023 g.L -1 ). RESUMEN. El objetivo del presente trabajo fue caracterizar fenotipicamente aislados de rizobios procedentes de la leguminosa forrajera Canavalia ensiformis. Se caracterizaron doce aislados, cinco posibles miembros del genero Rhizobium/ Sinorhizobium, siete posibles integrantes del genero Bradyrhizobium y dos cepas comerciales, BR 2001 y BR 2003a. Para la caracterizacion fenotipica de los aislados bacterianos se estudio su capacidad de utilizar seis fuentes de carbono, la tolerancia a condiciones de acidez y a diferentes niveles de cloruro de sodio (NaCl), la resistencia a seis antibioticos asi