31 resultados para papaína
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Lectin obtained from the marine sponge Tedania ignis was purified and characterized by extraction of soluble proteins (crude extract) in 50mM Borax, pH 7.5. The purification procedure was carried out by crude extract precipitation with ammonium sulfate 30% (FI). The precipitated was resuspended in the same buffer and fractionated with acetone 1.0 volume (F1.0). A lectin was purified from this specific fraction by using an affinity chromatography Sepharose 6B. This lectin preferentially agglutinated human erythrocytes from B type previously treated with papain enzyme. The hemagglutinating activity lectin was dependent of divalent Mn2+ cation and was inhibited by the carbohydrates galactose, xylose and fructose. SDS-PAGE analysis indicated a molecular mass of the lectin around 45 kDa. This protein showed stability until 40°C for 1 h. Further, it showed activity between pH 2.5 and 11.5, with an enhanced activity at pH 7.5. Leishmania chagasi promastigotes stained with Coomassie brilliant blue R-250 were agglutinated by F1,0 and in the presence of galactose this interaction was abolished. These results show that this lectin could be implicated in defense procedures and it will can be used as biological tools in studies with this protozoon
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No presente trabalho apresenta-se um método de cristalização da papaína oriunda do látex fresco de mamão, o qual apresenta uma alta produtividade em relação aos métodos previamente descritos. A metodologia aqui descrita não envolve o uso de reagentes sulfidrílicos, a papaína foi obtida de forma praticamente pura, apresentando uma simples banda quando submetida a eletroforese, e com propriedades idênticas àquelas obtidas por outros métodos. A atividade específica foi determinada utilizando Z-gly-pNP e BAEE como substrato. A papaína obtida por essa metodologia, sem uso de substâncias tais como cisteína e ditiotreitol, apresenta-se na forma de um complexo com inibidores naturais, os quais podem ser removidos por diálise.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Agronomia - FEIS
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Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB
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OBJECTIVE: Investigation of standard intensities of physical exercise is important to better comprehend and develop rehabilitation programs for emphysema. We aimed to evaluate the effects of different intensities (moderate and high-intensity) of physical exercise on the development of a protease-induced (papain intratracheal instillation) emphysema in rats. METHODS: Male Wistar rats were randomly separated into five groups that received intratracheal instillation of papain solution or vehicle: (i) papain high intensity exercise, (ii) papain moderate exercise, (iii) saline high intensity exercise, (iv) saline sedentary and (v) papain sedentary. Forty days after intratracheal instillation, the exercise groups were submitted to an exercise-training protocol on a treadmill during 10 weeks, 5 days/week, at 0.9 km/h (Papain and saline high exercise), or at 0.6 km/h (papain moderate exercise).We measured respiratory system elastance and resistance, the collagen fiber lung parenchyma, and the pulmonary mean linear intercept. RESULTS: All animal groups that received papain instillation presented higher alveolar wall destruction compared to animals that received only saline solution. The papain high intensity exercise group presented higher values of mean linear intercept compared to emphysema groups that were trained at a moderate intensity or not submitted to exercise. CONCLUSION: High intensity exercise training worsened alveolar destruction in an experimental model of emphysema in rats when compared to moderate intensity exercise, or to no exercise.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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La antesis de una flor es un estadio crucial para el destino del ovario ya que estímulos endógenos -polinización o nivel hormonal elevado- o exógenos -aplicación hormonal- inducen el proceso de fructificación. En ausencia de estos estímulos el ovario deja de crecer e inicia un proceso de senescencia. Previamente se ha observado que, en ovarios no polinizados, la senescencia va acompañada por un incremento en la actividad/expresión de ciertas tiol-proteasas, parámetros que disminuyen durante la etapa temprana del desarrollo de frutos. El objetivo fue analizar la localización de proteasas y los cambios anatómicos asociados a los procesos de fructificación o senescencia que se producen durante la etapa temprana del desarrollo de los frutos de tomate obtenidos por polinización natural o por tratamiento con AG3. Durante el período en que los ovarios no polinizados mantienen su sensibilidad a la aplicación hormonal, se observó una acumulación de polipéptidos relacionados antigénicamente con la tiol-proteasa papaína, principalmente en la epidermis del pericarpio, sin evidenciarse alteraciones en la integridad de los tejidos. Frutos de 8 días de desarrollo obtenidos con AG3, en comparación con los polinizados, evidenciaron un incremento en el espesor del pericarpio relacionado principalmente con una mayor elongación de las células del mesocarpio.
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Plant proteolysis is a metabolic process where specific enzymes called peptidases degrade proteins. In plants, this complex process involves broad metabolic networks and different sub-cellular compartments. Several types of peptidases take part in the proteolytic process, mainly cysteine-, serine-, aspartyl- and metallo- peptidases. Among the cysteine-peptidases, the papain-like or C1A peptidases (family C1, clan CA) are extensively present in land plants and are classified into catepsins L-, B-, H- and Flike. The catalytic mechanism of these C1A peptidases is highly conserved and involves the three amino acids Cys, His and Asn in the catalytic triad, and a Gln residue which seems essential for maintaining an active enzyme conformation. These proteins are synthesized as inactive precursors, which comprise an N-terminal signal peptide, a propeptide, and the mature protein. In barley, we have identified 33 cysteine-peptidases from the papain-like family, classifying them into 8 different groups. Five of them corresponded to cathepsins L-like (5 subgroups), 1 cathepsin B-like group, 1 cathepsin F-like group and 1 cathepsin H-like group. Besides, C1A peptidases are the specific targets of the plant proteinaceous inhibitors known as phytocystatins (PhyCys). The cystatin inhibitory mechanism is produced by a tight and reversible interaction with their target enzymes. In barley, the cystatin gene family is comprised by 13 members. In this work we have tried to elucidate the role of the C1A cysteine-peptidases and their specific inhibitors (cystatins) in the germination process of the barley grain. Therefore, we selected a representative member of each group/subgroup of C1A peptidases (1 cathepsin B-like, 1 cathepsin F-like, 1 cathepsin H-like and 5 cathepsins L-like). The molecular characterization of the cysteine-peptidases was done and the peptidase-inhibitor interaction was analyzed in vitro and in vivo. A study in the structural basis for specificity of pro-peptide/enzyme interaction in barley C1A cysteine-peptidases has been also carried out by inhibitory assays and the modeling of the three-dimensional structures. The barley grain maturation produces the accumulation of storage proteins (prolamins) in the endosperm which are mobilized during germination to supply the required nutrients until the photosynthesis is fully established. In this work, we have demonstrated the participation of the cysteine-peptidases and their inhibitors in the degradation of the different storage protein fractions (hordeins, albumins and globulins) present in the barley grain. Besides, transgenic barley plants overexpressing or silencing cysteine-peptidases or cystatins were obtained by Agrobacterium-mediated transformation of barley immature embryos to analyze their physiological function in vivo. Preliminary assays were carried out with the T1 grains of several transgenic lines. Comparing the knock-out and the overexpressing lines with the WT, alterations in the germination process were detected and were correlated with their grain hordein content. These data will be validated with the homozygous grains that are being produced through the double haploid technique by microspore culture. Resumen La proteólisis es un proceso metabólico por el cual se lleva a cabo la degradación de las proteínas de un organismo a través de enzimas específicas llamadas proteasas. En plantas, este complejo proceso comprende un entramado de rutas metabólicas que implican, además, diferentes compartimentos subcelulares. En la proteólisis participan numerosas proteasas, principalmente cisteín-, serín-, aspartil-, y metalo-proteasas. Dentro de las cisteín-proteasas, las proteasas tipo papaína o C1A (familia C1, clan CA) están extensamente representadas en plantas terrestres, y se clasifican en catepsinas tipo L, B, H y F. El mecanismo catalítico de estas proteasas está altamente conservado y la triada catalítica formada por los aminoácidos Cys, His y Asn, y a un aminoácido Gln, que parece esencial para el mantenimiento de la conformación activa de la proteína. Las proteasas C1A se sintetizan como precursores inactivos y comprenden un péptido señal en el extremo N-terminal, un pro-péptido y la proteína madura. En cebada hemos identificado 33 cisteín-proteasas de tipo papaína y las hemos clasificado filogenéticamente en 8 grupos diferentes. Cinco de ellos pertenecen a las catepsinas tipo L (5 subgrupos), un grupo a las catepsinas tipo-B, otro a las catepsinas tipo-F y un último a las catepsinas tipo-H. Las proteasas C1A son además las dianas específicas de los inhibidores protéicos de plantas denominados fitocistatinas. El mecanismo de inhibición de las cistatinas está basado en una fuerte interacción reversible. En cebada, se conoce la familia génica completa de las cistatinas, que está formada por 13 miembros. En el presente trabajo se ha investigado el papel de las cisteín-proteasas de cebada y sus inhibidores específicos en el proceso de la germinación de la semilla. Para ello, se seleccionó una proteasa representante de cada grupo/subgrupo (1 catepsina tipo- B, 1 tipo-F, 1 tipo-H, y 5 tipo-L, una por cada subgrupo). Se ha llevado a cabo su caracterización molecular y se ha analizado la interacción enzima-inhibidor tanto in vivo como in vitro. También se han realizado estudios sobre las bases estructurales que demuestran la especificidad en la interacción enzima/propéptido en las proteasas C1A de cebada, mediante ensayos de inhibición y la predicción de modelos estructurales de la interacción. Finalmente, y dado que durante la maduración de la semilla se almacenan proteínas de reserva (prolaminas) en el endospermo que son movilizadas durante la germinación para suministrar los nutrientes necesarios hasta que la nueva planta pueda realizar la fotosíntesis, en este trabajo se ha demostrado la participación de las cisteínproteasas y sus inhibidores en la degradación de las diferentes tipos de proteínas de reserva (hordeinas, albúmins y globulinas) presentes en el grano de cebada. Además, se han obtenido plantas transgénicas de cebada que sobre-expresan o silencian cistatinas y cisteín-proteasas con el fin de analizar la función fisiológica in vivo. Se han realizado análisis preliminares en las semillas T1 de varias líneas tránsgenicas de cebada y al comparar las líneas knock-out y las líneas de sobre-expresión con las silvestres, se han detectado alteraciones en la germinación que están además correlacionadas con el contenido de hordeinas de las semillas. Estos datos serán validados en las semillas homocigotas que se están generando mediante la técnica de dobles haploides a partir del cultivo de microesporas.
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A proteinaceous trypsin inhibitor was purified from Crotalaria pallida seeds by ammonium sulphate fractionation, affinity chromatography on immobilized Trypsin-Sepharose and TCA precipitation. The trypsin inhibitor, named ITC, had Mr of 32.5 kDa by SDS-PAGE and was composed by two subunits with 27.7 and 5.6 kDa linked by disulphide bridges, a typical characteristic of Kunitz-Inhibitor family. ITC was stable until 50°C, and at 100°C its residual activity was of about 60%. Also, ITC was stable at pHs 2 to 12. The inhibition of trypsin by ITC was non-competitive, with a Ki of 8,8 x 10-7M. ITC inhibits weakly other serine proteinases such as chymotrypsin and elastase. The inhibition of papain (44% of inhibition), a cysteine proteinase was an indicative of the bi-functionality of ITC. In vitro assays against digestive proteinases from several Lepdoptera, Diptera and Coleoptera pests were made. ITC inhibited in 100% digestive enzymes of Ceratitis capitata (fruit fly), Spodoptera frugiperda and Alabama argillacea, the last one being a cotton pest. It also inhibited in 74.4% Callosobruchus maculatus (bean weevil) digestive enzymes, a Coleoptera pest. ITC, when added in artificial diet models, affected weakly the development of C. capitata larvae and it had a WD50 of 2.65% to C. maculatus larvae
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Serines proteinases inhibitors (PIs) are widely distributed in nature and are able to inhibit both in vitro and in vivo enzymatic activites. Seed PIs in than leguminous are classified in seven families, Bowman-Birk and Kunitz type families that most studied representing an important role in the first line of defense toward insects pests. Some Kunitz type inhibitors possess activities serine and cysteine for proteinases named bifunctional inhibitor, as ApTKI the inhibitor isolate from seed of Adenanthera pavonina. The A. pavonina inhibitor presenting the uncommon property and was used for interaction studies between proteinases serine (trypsin) and cysteine (papain). In order to determinate the in vitro interaction of ApTKI against enzymes inhibitor purification was carried cut by using chromatographic techniques and inhibition assays. The 3D model of the bifunctional inhibitor ApTKI was constructed SWISS-MODEL program by homology modeling using soybean trypsin inhibitor (STI, pdb:1ba7), as template which presented 40% of identity to A. pavonina inhibitor. Model quality was evaluated by PROCHECK program. Moreover in silico analyzes of formed complex between the enzymes and ApTKI was evaluated by HEX 4.5 program. In vitro results confirmed the inhibitory assays, where the inhibitor presented the ability to simultaneously inhibit trypsin and papain. The residues encountered in the inhibitor model of folder structural three-dimensional that make contact to enzymes target coud explain the specificity pattern against serine and cysteine proteinases
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One Kunitz-type trypsin inhibitors (PmTI) was purified from Piptadenia moniliformis seeds, a tree of the sub-family Mimosoideae, by TCA precipitation, affinity chromatography on immobilized trypsin-Sepharose, DEAE cellulose (ion exchange) and Superose 12 (molecular exclusion) column FPLC/AKTA. The inhibitor has Mr of 25 kDa by SDS-PAGE and chromatography molecular exclusion. The N-terminal sequence of this inhibitor showed high homology with other family Kunitz inhibitors. This also stable variations in temperature and pH and showed a small decrease in its activity when incubated with DDT in the concentration of 100mM for 120 minutes. The inhibition of trypsin by PmTI was competitive, with Ki of 1.57 x10-11 M. The activity of trypsin was effectively inhibited by percentage of inhibition of 100%, among enzymes tested, was not detected inhibition for the bromelain, was weak inhibitor of pancreatic elastase (3.17% of inhibition) and inhibited by 76.42% elastase of neutrophils, and inhibited in a moderate, chymotrypsin and papain with percentage of inhibition of 42.96% and 23.10% respectively. In vitro assays against digestive proteinases from Lepidoptera, Diptera and Coleoptera pests were carried out. Several degrees of inhibition were found. For Anthonomus grandis and Ceratitis capitata the inhibition was 89.93% and 70.52%, respectively, and the enzymes of Zabrotes subfasciatus and Callosobruchus maculatus were inhibited by 5.96% and 9.41%, respectively, and the enzymes of Plodia. interpunctella and Castnia licus were inhibited by 59.94% and 23.67, respectively. In vivo assays, was observed reduction in the development of larvae in 4rd instar of C. capitata, when PmTI was added to the artificial diet, getting WD50 and LD50 of 0.30% and 0.33%, respectively. These results suggest that this inhibitor could be a strong candidate to plant management programs cross transgenic
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A chymotrypsin inhibitor was purified from Erythrina velutina seeds by ammonium sulphate fractionation, affinities chromatographies on Trypsin-Sepharose, Quimotrypsin-Sepharose and reversed phase C-18 FPLC/AKTA system. The inhibitor, named EvCI, shown molecular mass of 17 kDa, as determined by SDSPAGE. 2D-PAGE showed four isoinhibitors with pI values of 4,42, 4,63, 4,83 and 5,06, with molecular mass of 17 kDa each. The aminoacid sequence of EvCI was determined by MALDI-TOF-MS and showed a high similarity with other Kunitz-type inhibitor of Erythrina variegata. EvCI competitively inhibited chymotrypsin, with Ki of 4 x10-8 M, but did not inhibited trypsin, pancreatic elastase, bromelain and papain. The inhibitory activity of EvCI was stable over wide pH and temperature ranges. In the presence of DTT 100 mM for 120 min, EvCI lost 50 % of activity. Cytotoxicity was studied in HeLa, MDA, HepG2, K562 and PC3 cells after 72-h incubation period. EvCl inhibited HeLa cells growth with an IC50 value of 50 μg/ml. Subsequent studies in HeLa cells analysis of cell death by annexin V/PI double-staining and cell cycle, using flow cytometry. The results provide evidence for a cytostatic activity of EvCl and support further studies on potential application of this inhibitors as an antiproliferative agent in combined therapy against cervical cancer
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Lectin obtained from the marine sponge Tedania ignis was purified and characterized by extraction of soluble proteins (crude extract) in 50mM Borax, pH 7.5. The purification procedure was carried out by crude extract precipitation with ammonium sulfate 30% (FI). The precipitated was resuspended in the same buffer and fractionated with acetone 1.0 volume (F1.0). A lectin was purified from this specific fraction by using an affinity chromatography Sepharose 6B. This lectin preferentially agglutinated human erythrocytes from B type previously treated with papain enzyme. The hemagglutinating activity lectin was dependent of divalent Mn2+ cation and was inhibited by the carbohydrates galactose, xylose and fructose. SDS-PAGE analysis indicated a molecular mass of the lectin around 45 kDa. This protein showed stability until 40°C for 1 h. Further, it showed activity between pH 2.5 and 11.5, with an enhanced activity at pH 7.5. Leishmania chagasi promastigotes stained with Coomassie brilliant blue R-250 were agglutinated by F1,0 and in the presence of galactose this interaction was abolished. These results show that this lectin could be implicated in defense procedures and it will can be used as biological tools in studies with this protozoon