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1.
Braz Oral Res ; 35: e108, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34816896

RESUMEN

The present study sought to evaluate the protective effect of Epigallocatechin-3-gallate (EGCG) and commercial green tea (GT) on eroded dentin using in vitro and in situ experimental models. For the in vitro experiment, matrix metalloproteinases (MMPs) were extracted from demineralized human coronary dentin powder (citric acid, pH 2.3) and assessed via a colorimetric assay and electrophoresis in gelatin. The gels were exposed to buffers with: control (no treatment), 0.05% sodium fluoride (NaF), 0.12% chlorhexidine digluconate (CHX), GT infusion, and 0.1% EGCG, and their respective activity was analyzed by zymography. For the in situ experiment, 20 healthy volunteers (aged 20-32 years) participated in this single-center, blind, crossover study. The subjects wore upper removable devices containing four human dentin blocks. Erosive challenge (coke-1 min) was performed four times/day/5 days. Blocks were treated for 1 min with: control (No treatment), 0.05% NaF, 0.1% EGCG, and GT. Thereafter, the specimens were subjected to stylus profilometry and SEM. ANOVA was used to evaluate dentin roughness and wear, with a significance level of 5%. In the zymography analysis, 0.12% CHX, GT, and 0.1% EGCG were found to inhibit the action of MMPs; however, in the colorimetric assay, only green tea inhibited the activity of MMPs. There were no significant differences observed in dentin roughness or wear (p > 0.05). Herein, EGCG and GT inhibited the activity of endogenous proteases, resulting in protection against erosion-induced dentin damage; however, they could not prevent tooth tissue loss in situ.


Asunto(s)
Catequina , Erosión de los Dientes , Catequina/farmacología , Estudios Cruzados , Dentina , Humanos , , Erosión de los Dientes/prevención & control
2.
Braz. oral res. (Online) ; 35: e108, 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS, BBO - Odontología | ID: biblio-1350356

RESUMEN

Abstract The present study sought to evaluate the protective effect of Epigallocatechin-3-gallate (EGCG) and commercial green tea (GT) on eroded dentin using in vitro and in situ experimental models. For the in vitro experiment, matrix metalloproteinases (MMPs) were extracted from demineralized human coronary dentin powder (citric acid, pH 2.3) and assessed via a colorimetric assay and electrophoresis in gelatin. The gels were exposed to buffers with: control (no treatment), 0.05% sodium fluoride (NaF), 0.12% chlorhexidine digluconate (CHX), GT infusion, and 0.1% EGCG, and their respective activity was analyzed by zymography. For the in situ experiment, 20 healthy volunteers (aged 20-32 years) participated in this single-center, blind, crossover study. The subjects wore upper removable devices containing four human dentin blocks. Erosive challenge (coke-1 min) was performed four times/day/5 days. Blocks were treated for 1 min with: control (No treatment), 0.05% NaF, 0.1% EGCG, and GT. Thereafter, the specimens were subjected to stylus profilometry and SEM. ANOVA was used to evaluate dentin roughness and wear, with a significance level of 5%. In the zymography analysis, 0.12% CHX, GT, and 0.1% EGCG were found to inhibit the action of MMPs; however, in the colorimetric assay, only green tea inhibited the activity of MMPs. There were no significant differences observed in dentin roughness or wear (p > 0.05). Herein, EGCG and GT inhibited the activity of endogenous proteases, resulting in protection against erosion-induced dentin damage; however, they could not prevent tooth tissue loss in situ.

3.
Toxicol In Vitro ; 65: 104824, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32165152

RESUMEN

Soybean toxin (SBTX) is a protein isolated from soybean seeds and composed of two polypeptide subunits (17 and 27 kDa). SBTX has in vitro activity against phytopathogenic fungi such as Cercospora sojina, Aspergillus niger, and Penicillium herguei, and yeasts like Candida albicans, C. parapsilosis, Kluyveromyces marxiannus, and Pichia membranifaciens. The present study aimed to analyze in vitro whether SBTX causes any side effects on non-target bacterial and mammalian cells that could impede its potential use as a novel antifungal agent. SBTX at 100 µg/mL and 200 µg/mL did not hinder the growth of the bacteria Salmonella enterica (subspecies enterica serovar choleraesuis), Bacillus subtilis (subspecies spizizenii) and Staphylococcus aureus. Moreover, SBTX at concentrations up to 500 µg/mL did not significantly affect the viability of erythrocytes, neutrophils, and human intestinal Caco-2 cells. To study whether SBTX could induce relevant alterations in gene expression, in vitro DNA microarray experiments were conducted in which differentiated Caco-2 cells were exposed for 24 h to 100 µg/mL or 200 µg/mL SBTX. SBTX up-regulated genes involved in cell cycle and immune response pathways, but down-regulated genes that play a role in cholesterol biosynthesis and platelet degranulation pathways. Thus, although SBTX did not affect bacteria, nor induced cytotoxity in mammalian cells, it affected some biological pathways in the human Caco-2 cell line that warrants further investigation.


Asunto(s)
Antifúngicos/farmacología , Glicoproteínas/farmacología , Proteínas de Soja/farmacología , Animales , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Eritrocitos/efectos de los fármacos , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Neutrófilos/efectos de los fármacos , Análisis de Secuencia por Matrices de Oligonucleótidos , Transcriptoma/efectos de los fármacos
4.
Int J Biol Macromol ; 149: 432-442, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32004601

RESUMEN

Dermatophytes belonging to Trichophyton ssp. are important anthropophilic and zoophilic pathogens, which developed resistance to griseofulvin, the common antifungal drug used to treat dermatophytosis. In this context, Moringa oleifera seed proteins have been described as antifungal agents with potential applications. Thus, this work aimed to evaluate the antidermatophytic in vitro, focusing on mechanisms, and in vivo potential of Mo-CBP4, purified from M. oleifera seeds. Mo-CBP4was purified after protein extraction with 50 mM Tris-HCl buffer, pH 8.0, and chromatography on chitin and CM Sepharose™ columns and antidermatophytic potential of Mo-CBP4 evaluated in vitro and in vivo. In vitro, Mo-CBP4 reduced in 50% the germination of microconidia of Trichophyton mentagrophytes at 45 µM; but did not show inhibition of mycelial growth. Mo-CBP4 (45 µM) presents the inhibitory activity even when incubated with N-acetyl-d-glucosamine (NAG). Analysis of the mechanisms of Mo-CBP4 revealed an increase in membrane permeability, ROS overproduction and damage to cell wall leading to microconidia death. Furthermore, using in vivo models, Mo-CBP4 (5, 10 and 20 mg g-1) reduced the severity and time of dermatophytosis. Altogether, these findings indicate that Mo-CBP4 has great potential for the development of novel antifungal drugs for the clinical treatment of dermatophytosis.


Asunto(s)
Hidrogeles/farmacología , Moringa oleifera/química , Micosis/tratamiento farmacológico , Proteínas de Plantas/química , Alérgenos/efectos adversos , Alérgenos/química , Antifúngicos/química , Antifúngicos/farmacología , Quitina/química , Humanos , Hidrogeles/química , Micosis/microbiología , Micosis/patología , Proteínas de Plantas/farmacología , Semillas/química , Piel/efectos de los fármacos , Piel/patología , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/patogenicidad , Tiña/tratamiento farmacológico , Tiña/microbiología , Tiña/patología
5.
J Plant Physiol ; 245: 153110, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31918353

RESUMEN

Infection with Cowpea severe mosaic virus (CPSMV) represents one of the main limitations for cowpea (Vigna unguiculata L. Walp.) productivity due to the severity of the disease symptoms, frequency of incidence, and difficulties in dissemination control. This study aimed to identify the proteins and metabolic pathways associated with the susceptibility and resistance of cowpea plants to CPSMV. Therefore, we treated the seeds of a naturally susceptible cowpea genotype (CE-31) with the mutagenic agent ethyl methane sulfonate (EMS) and compared the secondary leaf proteomic profile of the mutagenized resistant plants inoculated with CPSMV (MCPI plant group) to those of the naturally susceptible cowpea genotype CE-31 inoculated (CPI) and noninoculated (CPU) with CPSMV. MCPI responded to CPSMV by accumulating proteins involved in the oxidative burst, increasing H2O2 generation, promoting leaf cell death (LCD), increasing the synthesis of defense proteins, and decreasing host factors important for the establishment of CPSMV infection. In contrast, CPI accumulated several host factors that favor CPSMV infection and did not accumulate H2O2 or present LCD, which allowed CPSMV replication and systemic dissemination. Based on these results, we propose that the differential abundance of defense proteins and proteins involved in the oxidative burst, LCD, and the decrease in cowpea protein factors required for CPSMV replication are associated with the resistance trait acquired by the MCPI plant group.


Asunto(s)
Comovirus/fisiología , Resistencia a la Enfermedad , Peróxido de Hidrógeno/metabolismo , Mutagénesis , Hojas de la Planta/virología , Vigna/metabolismo , Vigna/virología , Muerte Celular/genética , Muerte Celular/fisiología , Resistencia a la Enfermedad/genética , Resistencia a la Enfermedad/fisiología , Metanosulfonato de Etilo/química , Metanosulfonato de Etilo/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/fisiología , Ontología de Genes , Homeostasis/efectos de los fármacos , Homeostasis/genética , Homeostasis/fisiología , Interacciones Huésped-Patógeno/efectos de los fármacos , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/fisiología , Mutágenos/química , Mutágenos/farmacología , Oxidación-Reducción/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Fotosíntesis/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/virología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Proteínas de Plantas/efectos de los fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mapas de Interacción de Proteínas , Proteoma/efectos de los fármacos , Proteoma/genética , Proteoma/metabolismo , Proteoma/fisiología , Vigna/genética , Vigna/fisiología , Replicación Viral
6.
Int J Biol Macromol ; 143: 814-824, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31734363

RESUMEN

Plant proteins are emerging as an alternative to conventional treatments against candidiasis. The aim of this study was to better understand the mechanism of action of Mo-CBP2 against Candida spp, evaluating redox system activity, lipid peroxidation, DNA degradation, cytochrome c release, medium acidification, and membrane interaction. Anti-candida activity of Mo-CBP2 decreased in the presence of ergosterol, which was not observed with antioxidant agents. C. albicans treated with Mo-CBP2 also had catalase and peroxidase activities inhibited, while superoxide dismutase was increased. Mo-CBP2 increased the lipid peroxidation, but it did not alter the ergosterol profile in live cells. External medium acidification was strongly inhibited, and cytochrome c release and DNA degradation were detected. Mo-CBP2 interacts with cell membrane constituents, changes redox system enzymes in C. albicans and causes lipid peroxidation by ROS overproduction. DNA degradation and cytochrome c release suggest apoptotic or DNAse activity. Lipid peroxidation and H+-ATPases inhibition may induce the process of apoptosis. Finally, Mo-CBP2 did not have a cytotoxic effect in mammalian Vero cells. This study highlights the biotechnological potential of Mo-CBP2 as a promising molecule with low toxicity and potent activity. Further studies should be performed to better understand its mode of action and toxicity.


Asunto(s)
Candida/efectos de los fármacos , Membrana Celular/metabolismo , Moringa oleifera/química , Proteínas de Plantas/farmacología , Semillas/química , Esteroles/metabolismo , Animales , Antifúngicos/farmacología , Antioxidantes/farmacología , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Citocromos c/metabolismo , Fragmentación del ADN/efectos de los fármacos , Ergosterol/metabolismo , Glucosa/farmacología , Itraconazol/farmacología , Peroxidación de Lípido/efectos de los fármacos , Nistatina/farmacología , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismo , Células Vero
7.
Food Chem Toxicol ; 136: 110977, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31759068

RESUMEN

Jaburetox (JBTX) is an insecticidal and antifungal peptide derived from jack bean (Canavalia ensiformis) urease that has been considered a candidate for developing genetically modified crops. This study aimed to perform the risk assessment of the peptide JBTX following the general recommendations of the two-tiered, weight-of-evidence approach proposed by International Life Sciences Institute. The urease of C. ensiformis (JBU) and its isoform JBURE IIb (the JBTX parental protein) were assessed. The history of safe use revealed no hazard reports for the studied proteins. The available information shows that JBTX possesses selective activity against insects and fungi. JBTX and JBU primary amino acids sequences showed no relevant similarity to toxic, antinutritional or allergenic proteins. Additionally, JBTX and JBU were susceptible to in vitro digestibility, and JBU was also susceptible to heat treatment. The results did not identify potential risks of adverse effects and reactions associated to JBTX. However, further allergen (e.g. serum IgE binding test) and toxicity (e.g. rodent toxicity tests) experimentation can be done to gather additional safety information on JBTX, and to meet regulatory inquiries for commercial approval of transgenic cultivars expressing this peptide.


Asunto(s)
Antifúngicos/toxicidad , Insecticidas/toxicidad , Proteínas de Plantas/toxicidad , Medición de Riesgo , Ureasa/toxicidad , Animales , Antifúngicos/química , Canavalia/enzimología , Biología Computacional , Hongos/efectos de los fármacos , Insectos/efectos de los fármacos , Insecticidas/química , Proteínas de Plantas/química , Isoformas de Proteínas/química , Isoformas de Proteínas/toxicidad , Proteolisis , Ureasa/química
8.
J Proteomics ; 194: 200-217, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30471437

RESUMEN

In nature, plants are simultaneously challenged by biotic and abiotic stresses. However, little is known about the effects of these combined stresses for most crops. This work aimed to evaluate the responsed of the virus-resistant cowpea genotype BRS-Marataoã to the exposure of salt stress combined with CPSMV infection. Cowpea plants were exposed to 200 mM NaCl either simultaneously (SV plant group) or 24 h prior to the CPSMV infection [S(24 h)V plant group]. Physiological, biochemical, and proteomic analyses at 2 and 6 days post salt stress (DPS) revealed that cowpea significantly reprogrammed its cellular metabolism. Indeed, plant size, photosynthetic parameters (net photosynthesis, transpiration rate, stomatal conductance, and internal CO2 partial pressure) and chlorophyll and carotenoid contents were reduced in S(24 h)V compared to SV. Moreover, accumulation of viral particles at 6 DPS in S(24 h)V was observed indicating that the salt stress imposed prior to virus infection favors viral particle proliferation. Proteomic analysis showed differential contents of 403 and 330 proteins at 2 DPS and 6 DPS, respectively, out of 733 differentially abundant proteins between the two plant groups. The altered leaf proteins are involved in energy and metabolism, photosynthesis, stress response, and oxidative burst. BIOLOGICAL SIGNIFICANCE: This is an original study in which a virus-resistant cowpea genotype (BRS-Marataoã) was (i) exposed simultaneously to 200 mM NaCl and inoculation with CPSMV (SV plant group) or (ii) exposed to 200 mM NaCl stress 24 h prior to inoculation with CPSMV [S(24 h)V plant group]. The purpose was to shed light on how this CPSMV resistant cowpea responded to the combined stresses. Numerous key proteins and associated pathways were altered in the cowpea plants challenged with both stresses, but unexpectedly, the salt stress imposed 24 h prior to CPSMV inoculation allowed viral proliferation, turning the cowpea genotype from resistant to susceptible.


Asunto(s)
Comovirus/metabolismo , Genotipo , Enfermedades de las Plantas/virología , Proteínas de Plantas/metabolismo , Estrés Salino , Vigna , Proteómica , Vigna/genética , Vigna/metabolismo , Vigna/virología
9.
J Sci Food Agric ; 97(11): 3790-3801, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28139827

RESUMEN

BACKGROUND: During the last few years, a growing number of antimicrobial peptides have been isolated from plants and particularly from seeds. Recent results from our laboratory have shown the purification of a new trypsin inhibitor, named CaTI, from chilli pepper (Capsicum annuum L.) seeds. This study aims to evaluate the antifungal activity and mechanism of action of CaTI on phytopathogenic fungi and detect the presence of protease inhibitors in other species of this genus. RESULTS: Our results show that CaTI can inhibit the growth of the phytopathogenic fungi Colletotrichum gloeosporioides and C. lindemuthianum. CaTI can also permeabilize the membrane of all tested fungi. When testing the inhibitor on its ability to induce reactive oxygen species, an induction of reactive oxygen species (ROS) and nitric oxide (NO) particularly in Fusarium species was observed. Using CaTI coupled to fluorescein isothiocyanate (FITC), it was possible to determine the presence of the inhibitor inside the hyphae of the Fusarium oxysporum fungus. The search for protease inhibitors in other Capsicum species revealed their presence in all tested species. CONCLUSION: This paper shows the antifungal activity of protease inhibitors such as CaTI against phytopathogenic fungi. Antimicrobial peptides, among which the trypsin protease inhibitor family stands out, are present in different species of the genus Capsicum and are part of the chemical arsenal that plants use to defend themselves against pathogens. © 2017 Society of Chemical Industry.


Asunto(s)
Capsicum/química , Fungicidas Industriales/farmacología , Estrés Oxidativo/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Extractos Vegetales/farmacología , Semillas/química , Inhibidores de Tripsina/farmacología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Colletotrichum/efectos de los fármacos , Colletotrichum/crecimiento & desarrollo , Colletotrichum/metabolismo , Fungicidas Industriales/química , Fungicidas Industriales/aislamiento & purificación , Fungicidas Industriales/metabolismo , Fusarium/efectos de los fármacos , Fusarium/crecimiento & desarrollo , Fusarium/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Inhibidores de Tripsina/química , Inhibidores de Tripsina/aislamiento & purificación , Inhibidores de Tripsina/metabolismo
10.
Protein Expr Purif ; 132: 97-107, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28161544

RESUMEN

Proteins extracted from Capsicum annuum L. fruits were initially subjected to reversed-phase chromatography on HPLC, resulting in eight peptide-rich fractions. All the fractions obtained were tested for their ability to inhibit porcine trypsin and amylase from both human saliva and from larval insect in vitro. All fractions were also tested for their ability to inhibit growth of the phytopathogenic fungi. Several fractions inhibited the activity of human salivary amylase and larval insect amylase, especially fraction Fa5. No fraction tested was found to inhibit trypsin activity, being Fa2 fraction an exception. Interestingly fraction Fa5 also displayed high antimicrobial activity against the species of the Fusarium genus. Fraction Fa5 was found to have two major protein bands of 17 and 6.5 kDa, and these were sequenced by mass spectrometry. Two peptides were obtained from the 6.5-kDa band, which showed similarity to antimicrobial peptides. Fraction Fa5 was also tested for its ability to permeabilize membranes and induce ROS. Fraction Fa5 was able to permeabilize the membranes of all the fungi tested. Fungi belonging to the genus Fusarium also showed an increase in the endogenous production of ROS when treated with this fraction. Antimicrobial peptides were also identified in the fruits from other Capsicum species.


Asunto(s)
Antiinfecciosos , Capsicum/química , Inhibidores Enzimáticos , Frutas/química , Fusarium/crecimiento & desarrollo , Péptidos , Proteínas de Plantas , alfa-Amilasas/antagonistas & inhibidores , Animales , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores Enzimáticos/farmacología , Humanos , Péptidos/química , Péptidos/aislamiento & purificación , Péptidos/farmacología , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/farmacología , Porcinos
11.
Planta Med ; 82(7): 596-605, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27093245

RESUMEN

Lectins are proteins that bind to specific mono- or oligosaccharides. This study aimed to evaluate the antinociceptive and anti-inflammatory effects of the lectin from the red marine alga Solieria filiformis. The animals (n = 6) were pretreated with S. filiformis lectin 30 min before they were given the nociceptive or inflammatory stimulus. The antinociceptive activity was evaluated in Swiss mice using the abdominal writhing, formalin, and hot plate tests. The anti-inflammatory properties were evaluated in Wistar rats using carrageenan-induced peritonitis and paw edema induced by different phlogistic agents. The S. filiformis lectin toxicity was assayed through its application in mice (7 days). S. filiformis lectin significantly reduced the number of abdominal writhings and reduced the paw licking time in the second phase of the formalin test (p < 0.05), but it did not prolong the reaction time in the hot plate test (p > 0.05). Furthermore, S. filiformis lectin reduced neutrophil migration in a peritonitis model and reduced paw edema induced by carrageenan, dextran, and serotonin (p < 0.05). Additionally, the administration of S. filiformis lectin resulted in no signs of systemic damage. Thus, S. filiformis lectin appears to have important antinociceptive and anti-inflammatory activities and could represent a potential therapeutic agent for future studies.


Asunto(s)
Analgésicos/aislamiento & purificación , Antiinflamatorios no Esteroideos/aislamiento & purificación , Lectinas/aislamiento & purificación , Rhodophyta/química , Analgésicos/farmacología , Animales , Antiinflamatorios no Esteroideos/farmacología , Femenino , Lectinas/farmacología , Masculino , Ratones , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/farmacología , Ratas , Ratas Wistar
12.
Phytochemistry ; 118: 224-35, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26330217

RESUMEN

Herein described is the biochemical characterisation, including in vitro and in vivo assays, for a proteinase inhibitor purified from Clitoria fairchildiana seeds (CFPI). Purification was performed by hydrophobic interaction and gel filtration chromatography. Kinetic studies of the purified inhibitor showed a competitive-type inhibitory activity against bovine trypsin and chymotrypsin, with an inhibition stoichiometry of 1:1 for both enzymes. The inhibition constants against trypsin and chymotrypsin were 3.3 × 10(-10) and 1.5 × 10(-10)M, respectively, displaying a tight binding property. SDS-PAGE showed that CFPI has a single polypeptide chain with an apparent molecular mass of 15 kDa under non-reducing conditions. However, MALDI-TOF analysis demonstrated a molecular mass of 7.973 kDa, suggesting that CFPI is dimeric in solution. The N-terminal sequence of CFPI showed homology with members of the Bowman-Birk inhibitor family. CFPI remained stable to progressive heating for 30 min to each temperature range of 37 up to 100 °C and CD analysis exhibited no changes in spectra at 207 nm after heating at 90 °C and subsequent cooling. Moreover, CFPI was active over a wide pH range (2-10). In contrast, reduction with DTT resulted in a loss of inhibitory activity against trypsin and chymotrypsin. CFPI also exhibited significant inhibitory activity against larval midgut trypsin enzymes from Anagasta kuehniella (76%), Diatraea saccharalis (59%) and Heliothis virescens (49%). Its insecticidal properties were further analysed by bioassays and confirmed by negative impact on A. kuehniella development.


Asunto(s)
Clitoria/química , Insecticidas , Inhibidores de Proteasas , Semillas/química , Animales , Bovinos , Quimotripsina/análisis , Insecticidas/química , Insecticidas/aislamiento & purificación , Insecticidas/farmacología , Cinética , Larva/efectos de los fármacos , Larva/metabolismo , Peso Molecular , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/metabolismo , Inhibidores de Proteasas/química , Inhibidores de Proteasas/aislamiento & purificación , Inhibidores de Proteasas/farmacología , Tripsina/análisis
13.
Acta Biochim Biophys Sin (Shanghai) ; 47(9): 716-29, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26245301

RESUMEN

Antimicrobial peptides (AMPs) are produced by a range of organisms as a first line of defense against invaders or competitors. Owing to their broad antimicrobial activity, AMPs have attracted attention as a potential source of chemotherapeutic drugs. The increasing prevalence of infections caused by Candida species as opportunistic pathogens in immunocompromised patients requires new drugs. Lecythis pisonis is a Lecythydaceae tree that grows in Brazil. The AMPs produced by this tree have not been described previously. We describe the isolation of 12 fractions enriched in peptides from L. pisonis seeds. Of the 12 fractions, at 10 µg/ml, the F4 fraction had the strongest growth inhibitory effect (53.7%) in Candida albicans, in addition to a loss of viability of 94.9%. The F4 fraction was separated into seven sub-fractions by reversed-phase chromatography. The F4.7' fraction had the strongest activity at 10 µg/ml, inhibiting C. albicans growth by 38.5% and a 69.3% loss of viability. The peptide in F4.7' was sequenced and was found to be similar to plant defensins. For this reason, the peptide was named L. pisonis defensin 1 (Lp-Def1). The mechanism of action that is responsible for C. albicans inhibition by Lp-Def1 includes a slight increase of reactive oxygen species induction and a significant loss of mitochondrial function. The results described here support the future development of plant defensins, specifically Lp-Def1, as new therapeutic substances against fungi, especially C. albicans.


Asunto(s)
Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Magnoliopsida/embriología , Péptidos/farmacología , Semillas/química , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Candida albicans/crecimiento & desarrollo , Candida albicans/metabolismo , Cromatografía de Fase Inversa , Electroforesis en Gel de Poliacrilamida , Pruebas de Sensibilidad Microbiana , Péptidos/química , Péptidos/aislamiento & purificación , Especies Reactivas de Oxígeno/metabolismo
14.
Food Chem Toxicol ; 81: 81-91, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25890087

RESUMEN

Cry8Ka5 is a mutant protein from Bacillus thuringiensis (Bt) that has been proposed for developing transgenic plants due to promising activity against coleopterans, like Anthonomus grandis (the major pest of Brazilian cotton culture). Thus, an early food safety assessment of Cry8Ka5 protein could provide valuable information to support its use as a harmless biotechnological tool. This study aimed to evaluate the food safety of Cry8Ka5 protein following the two-tiered approach, based on weights of evidence, proposed by ILSI. Cry1Ac protein was used as a control Bt protein. The history of safe use revealed no convincing hazard reports for Bt pesticides and three-domain Cry proteins. The bioinformatics analysis with the primary amino acids sequence of Cry8Ka5 showed no similarity to any known toxic, antinutritional or allergenic proteins. The mode of action of Cry proteins is well understood and their fine specificity is restricted to insects. Cry8Ka5 and Cry1Ac proteins were rapidly degraded in simulated gastric fluid, but were resistant to simulated intestinal fluid and heat treatment. The LD50 for Cry8Ka5 and Cry1Ac was >5000 mg/kg body weight when administered by gavage in mice. Thus, no expected relevant risks are associated with the consumption of Cry8Ka5 protein.


Asunto(s)
Proteínas Bacterianas/efectos adversos , Endotoxinas/efectos adversos , Inocuidad de los Alimentos , Proteínas Hemolisinas/efectos adversos , Proteínas Mutantes/efectos adversos , Pruebas de Toxicidad Aguda/métodos , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Secuencia de Aminoácidos , Animales , Aspartato Aminotransferasas/sangre , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Recuento de Células Sanguíneas , Colesterol/sangre , Biología Computacional , Creatinina/sangre , Endotoxinas/genética , Femenino , Proteínas Hemolisinas/genética , Insectos , Insecticidas , Dosificación Letal Mediana , Ratones , Datos de Secuencia Molecular , Proteínas Mutantes/genética , Tamaño de los Órganos/efectos de los fármacos , Control Biológico de Vectores , Plantas Modificadas Genéticamente/genética , Triglicéridos/sangre , Urea/sangre
15.
Biomed Res Int ; 2014: 810490, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25165717

RESUMEN

Studies have contested the innocuousness of Bacillus thuringiensis (Bt) Cry proteins to mammalian cells as well as to mammals microbiota. Thus, this study aimed to evaluate the cytotoxic and antimicrobial effects of two Cry proteins, Cry8Ka5 (a novel mutant protein) and Cry1Ac (a widely distributed protein in GM crops). Evaluation of cyto- and genotoxicity in human lymphocytes was performed as well as hemolytic activity coupled with cellular membrane topography analysis in mammal erythrocytes. Effects of Cry8Ka5 and Cry1Ac upon Artemia sp. nauplii and upon bacteria and yeast growth were assessed. The toxins caused no significant effects on the viability (IC50 > 1,000 µg/mL) or to the cellular DNA integrity of lymphocytes (no effects at 1,000 µg/mL). The Cry8Ka5 and Cry1Ac proteins did not cause severe damage to erythrocytes, neither with hemolysis (IC50 > 1,000 µg/mL) nor with alterations in the membrane. Likewise, the Cry8Ka5 and Cry1Ac proteins presented high LC50 (755.11 and >1,000 µg/mL, resp.) on the brine shrimp lethality assay and showed no growth inhibition of the microorganisms tested (MIC > 1,000 µg/mL). This study contributed with valuable information on the effects of Cry8Ka5 and Cry1Ac proteins on nontarget organisms, which reinforce their potential for safe biotechnological applications.


Asunto(s)
Bacillus thuringiensis/genética , Proteínas Bacterianas/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Proteínas Mutantes/genética , Plantas Modificadas Genéticamente/genética , Animales , Artemia/efectos de los fármacos , Bacillus thuringiensis/química , Toxinas de Bacillus thuringiensis , Bacterias/efectos de los fármacos , Proteínas Bacterianas/administración & dosificación , Proliferación Celular/efectos de los fármacos , Endotoxinas/administración & dosificación , Eritrocitos/efectos de los fármacos , Proteínas Hemolisinas/administración & dosificación , Humanos , Linfocitos/efectos de los fármacos , Proteínas Mutantes/administración & dosificación , Control Biológico de Vectores
16.
BMC Biotechnol ; 13: 46, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23725035

RESUMEN

BACKGROUND: Chromobacterium violaceum is a free-living ß-proteobacterium found in tropical and subtropical regions. The genomic sequencing of C. violaceum ATCC 12472 has revealed many genes that underpin its adaptability to diverse ecosystems. Moreover, C. violaceum genes with potential applications in industry, medicine and agriculture have also been identified, such as those encoding chitinases. However, none of the chitinase genes of the ATCC 12472 strain have been subjected to experimental validation. Chitinases (EC 3.2.1.14) hydrolyze the ß-(1,4) linkages in chitin, an abundant biopolymer found in arthropods, mollusks and fungi. These enzymes are of great biotechnological interest as potential biocontrol agents against pests and pathogens. This work aimed to experimentally validate one of the chitinases from C. violaceum. RESULTS: The open reading frame (ORF) CV2935 of C. violaceum ATCC 12472 encodes a protein (439 residues) that is composed of a signal peptide, a chitin-binding domain, a linker region, and a C-terminal catalytic domain belonging to family 18 of the glycoside hydrolases. The ORF was amplified by PCR and cloned into the expression vector pET303/CT-His. High levels of chitinolytic activity were detected in the cell-free culture supernatant of E. coli BL21(DE3) cells harboring the recombinant plasmid and induced with IPTG. The secreted recombinant protein was purified by affinity chromatography on a chitin matrix and showed an apparent molecular mass of 43.8 kDa, as estimated by denaturing polyacrylamide gel electrophoresis. N-terminal sequencing confirmed the proper removal of the native signal peptide during the secretion of the recombinant product. The enzyme was able to hydrolyze colloidal chitin and the synthetic substrates p-nitrophenyl-ß-D-N,N'-diacetylchitobiose and p-nitrophenyl-ß-D-N,N',N"-triacetylchitotriose. The optimum pH for its activity was 5.0, and the enzyme retained ~32% of its activity when heated to 60°C for 30 min. CONCLUSIONS: A C. violaceum chitinase was expressed in E. coli and purified by affinity chromatography on a chitin matrix. The secretion of the recombinant protein into the culture medium was directed by its native signal peptide. The mature enzyme was able to hydrolyze colloidal chitin and synthetic substrates. This newly identified signal peptide is a promising secretion factor that should be further investigated in future studies, aiming to demonstrate its usefulness as an alternative tool for the extracellular production of recombinant proteins in E. coli.


Asunto(s)
Quitinasas/biosíntesis , Chromobacterium/enzimología , Escherichia coli/metabolismo , Secuencia de Aminoácidos , Cromatografía de Afinidad , Clonación Molecular , Vectores Genéticos , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Proteínas Recombinantes/biosíntesis , Alineación de Secuencia , Especificidad por Sustrato
17.
Biomed Res Int ; 2013: 578781, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23691507

RESUMEN

Among the Bauhinia species, B. cheilantha stands out for its seed protein content. However, there is no record of its nutritional value, being used in a nonsustainable way in the folk medicine and for large-scale extraction of timber. The aim of this study was to investigate the food potential of B. cheilantha seeds with emphasis on its protein quality to provide support for flora conservation and use as raw material or as prototype for the development of bioproducts with high added socioeconomic value. B. cheilantha seeds show high protein content (35.9%), reasonable essential amino acids profile, low levels of antinutritional compounds, and nutritional parameters comparable to those of legumes widely used such as soybean and cowpea. The heat treatment of the seeds as well as the protein extraction process (to obtain the protein concentrate) increased the acceptance of diets by about 100% when compared to that of raw Bc diet. These wild legume seeds can be promising alternative source of food to overcome the malnutrition problem faced by low income people adding socioeconomic value to the species.


Asunto(s)
Bauhinia/química , Clima Desértico , Medicina Tradicional , Valor Nutritivo , Semillas/química , Pruebas de Toxicidad , Aminoácidos/análisis , Animales , Lectinas/metabolismo , Masculino , Ratones , Ratas , Ratas Wistar , Semillas/enzimología , Tripsina/metabolismo , Ureasa/metabolismo
18.
Protein Pept Lett ; 20(10): 1153-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23578141

RESUMEN

The marine ecosystem is able to provide enormous biomolecule diversity that could be used for treatment of various diseases. In this highly competitive environment, organisms need chemical barriers to reduce or avoid microorganism contamination. Among the molecules that protect these animals the antimicrobial peptides (AMPs) are included. In the present study, crude extracts of coral coral specimens Carijoa riisei, Muriceopsis sulphurea, Neospongodes atlantica, Palythoa caribeorum, Phyllogorgia dilatata and Plexaurella grandiflora were challenged against multiple Grampositive and -negative bacteria showing different activities. P. dilatata crude extract showed the antibacterial activity, and was ammonium-sulfate (0-40%) fractionated, being able to control the growth of K. pneumoniae, S. flexineri and S. aureus. Rich-fraction was further purified by using Amicon® Ultra Centrifugal 10 kDa associated with reversed-phase HPLC chromatography (C18), producing the peptide named Pd-AMP1. Pd-AMP1 was able to inhibit S. aureus development. Mass spectrometry analyses showed a monoisotopic mass of 5372.66 Da and N-terminal sequence showed no significant match with databank. In this view, the prospecting of protein biomolecules and biotechnological potential from marine animals is still little explored and may serve as an alternative to common antibiotics.


Asunto(s)
Antozoos/química , Antibacterianos/química , Antibacterianos/farmacología , Péptidos/química , Péptidos/farmacología , Secuencia de Aminoácidos , Animales , Antibacterianos/aislamiento & purificación , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Brasil , Humanos , Datos de Secuencia Molecular , Péptidos/aislamiento & purificación
19.
Biomed Res Int ; 2013: 510736, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24386637

RESUMEN

The antimicrobial, antioxidant, and anticholinesterase activities of ethanolic seed extracts of twenty-one plant species from Brazilian semiarid region were investigated. The extracts were tested for antimicrobial activity against six bacteria strains and three yeasts. Six extracts presented activity against the Gram (-) organism Salmonella choleraesuis and the Gram (+) organisms Staphylococcus aureus and Bacillus subtilis. The MIC values ranged from 4.96 to 37.32 mg/mL. The Triplaris gardneriana extract presented activity against the three species, with MIC values 18.8, 13.76, and 11.15 mg/mL, respectively. Five extracts presented antioxidant activity, with EC50 values ranging from 69.73 µ g/mL (T. gardneriana) to 487.51 µ g/mL (Licania rigida). For the anticholinesterase activity, eleven extracts were capable of inhibiting the enzyme activity. From those, T. gardneriana, Parkia platycephala and Connarus detersus presented the best activities, with inhibition values of 76.7, 71.5, and 91.9%, respectively. The extracts that presented antimicrobial activity were tested for hemolytic assay against human A, B, and O blood types and rabbit blood. From those, only the Myracrodruon urundeuva extract presented activity (about 20% of hemolysis at the lowest tested concentration, 1.9 µg/mL). Infrared spectroscopy of six representative extracts attested the presence of tannins, polyphenols, and flavonoids, which was confirmed by a qualitative phytochemical assay.


Asunto(s)
Anacardiaceae/química , Antibacterianos/farmacología , Antioxidantes/farmacología , Inhibidores de la Colinesterasa/farmacología , Extractos Vegetales/farmacología , Animales , Bacillus subtilis/efectos de los fármacos , Brasil , Colinesterasas/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/clasificación , Conejos , Salmonella/efectos de los fármacos , Semillas/química
20.
Molecules ; 17(7): 7854-63, 2012 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-22743589

RESUMEN

The objective of this study was to evaluate the reactivity of an in-house antigen, extracted from a strain of C. posadasii isolated in northeastern Brazil, by radial immunodiffusion and Western blotting, as well as to establish its biochemical characterization. The protein antigen was initially extracted with the use of solid ammonium sulfate and characterized by 1-D electrophoresis. Subsequently, it was tested by means of double radial immunodiffusion and Western blotting. A positive reaction was observed against the antigen by both immunodiagnostic techniques tested on sera from patients suffering from coccidioidomycosis. Besides this, two immunoreactive protein bands were observed and were revealed to be a ß-glucosidase and a glutamine synthetase after sequencing of the respective N-terminal regions. Our in-house Coccidioides antigen can be promising as a quick and low-cost diagnostic tool without the risk of direct manipulation of the microorganism.


Asunto(s)
Antígenos Fúngicos/inmunología , Coccidioides/inmunología , Coccidioidomicosis/diagnóstico , Coccidioidomicosis/inmunología , Pruebas Inmunológicas/métodos , Secuencia de Aminoácidos , Antígenos Fúngicos/química , Electroforesis en Gel de Poliacrilamida , Humanos , Datos de Secuencia Molecular , Peso Molecular
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