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1.
Bol. latinoam. Caribe plantas med. aromát ; 22(5): 649-656, sep. 2023. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1561291

RESUMO

The conversion factor of nitrogen to proteins and isoflavones present in Glycine max was determined. For the determination of the conversion factor, we worked with solubilizing the proteins at alkaline pH and then extracting them with acidic pH. The proteins were identified by the Kjeldahl method. The antioxidant capacity was determined after extracting the isoflavones and their glycosides through the Soxhlet method, and then using the Brand Williams method (DPPH). The results indicate that the protein conversion factor was 5.85, the maximum concentration of total isoflavones was 33.33%, the antiradical efficiency of total isoflavones was 0.004 mL/ug min, the antiradical efficiency of gallic acid was 0.005 mL/ug min. and the antiradical efficiency of tannic acid was 0.0004 mL/ugmin. These results justify the consumption of Glycine max (Soya) as a food that has a high nutritional quality and provides an excellent source of antioxidants, which will prevent hormonal and carcinogenic diseases.


Se determinó el factor de conversión de nitrógeno a proteínas e isoflavonas presentes en Glycine max. Para la determinación del factor de conversión se trabajó con solubilizando las proteínas a pH alcalinos y luego extrayéndolas con pH ácidos. Las proteínas fueron identificadas por el método Kjeldahl. La capacidad antioxidante se determinó previa extracción de las isoflavonas y sus glicósidos a través del método de Soxhlet, y luego empleando el método de Brand Williams (DPPH).Los resultados indican que el factor de conversión proteica fue 5,85, la concentración máxima de isoflavonas totales fue 33,33 %, la eficiencia antirradicalaria de las isoflavonas totales fue 0,004 mL/ug min, la eficiencia antirradicalaria de ácido gálico fue 0,005 mL/ug min y la eficiencia antirradicalaria de ácido tánico fue 0,0004 mL/ug min. Estos resultados justifican el consumo de Glycine max (Soya) como un alimento que posee una alta calidad nutricional y proporciona una óptima fuente de antioxidantes, que permitirá prevenir enfermedades hormonales y cancerígenas.


Assuntos
Proteínas de Plantas/farmacologia , Conformação Proteica , Glycine max/química , Isoflavonas/farmacologia , Proteínas de Plantas/metabolismo , Plantas Medicinais , Glycine max/metabolismo
2.
Braz. j. biol ; 83: e245379, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339405

RESUMO

Abstract Population growth is increasing rapidly around the world, in these consequences we need to produce more foods to full fill the demand of increased population. The world is facing global warming due to urbanizations and industrialization and in this concerns plants exposed continuously to abiotic stresses which is a major cause of crop hammering every year. Abiotic stresses consist of Drought, Salt, Heat, Cold, Oxidative and Metal toxicity which damage the crop yield continuously. Drought and salinity stress severally affected in similar manner to plant and the leading cause of reduction in crop yield. Plants respond to various stimuli under abiotic or biotic stress condition and express certain genes either structural or regulatory genes which maintain the plant integrity. The regulatory genes primarily the transcription factors that exert their activity by binding to certain cis DNA elements and consequently either up regulated or down regulate to target expression. These transcription factors are known as masters regulators because its single transcript regulate more than one gene, in this context the regulon word is fascinating more in compass of transcription factors. Progress has been made to better understand about effect of regulons (AREB/ABF, DREB, MYB, and NAC) under abiotic stresses and a number of regulons reported for stress responsive and used as a better transgenic tool of Arabidopsis and Rice.


Resumo O crescimento populacional está aumentando rapidamente em todo o mundo, e para combater suas consequências precisamos produzir mais alimentos para suprir a demanda do aumento populacional. O mundo está enfrentando o aquecimento global devido à urbanização e industrialização e, nesse caso, plantas expostas continuamente a estresses abióticos, que é uma das principais causas do martelamento das safras todos os anos. Estresses abióticos consistem em seca, sal, calor, frio, oxidação e toxicidade de metais que prejudicam o rendimento da colheita continuamente. A seca e o estresse salino são afetados de maneira diversa pela planta e são a principal causa de redução da produtividade das culturas. As plantas respondem a vários estímulos sob condições de estresse abiótico ou biótico e expressam certos genes estruturais ou regulatórios que mantêm a integridade da planta. Os genes reguladores são principalmente os fatores de transcrição que exercem sua atividade ligando-se a certos elementos cis do DNA e, consequentemente, são regulados para cima ou para baixo para a expressão alvo. Esses fatores de transcrição são conhecidos como reguladores mestres porque sua única transcrição regula mais de um gene; nesse contexto, a palavra regulon é mais fascinante no âmbito dos fatores de transcrição. Progresso foi feito para entender melhor sobre o efeito dos regulons (AREB / ABF, DREB, MYB e NAC) sob estresses abióticos e uma série de regulons relatados como responsivos ao estresse e usados ​​como uma melhor ferramenta transgênica de Arabidopsis e Rice.


Assuntos
Regulon/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Plantas Geneticamente Modificadas/genética , Secas
3.
Biol. Res ; 55: 27-27, 2022. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1447503

RESUMO

BACKGROUND: Cytokinin signal transduction is mediated by a two-component system (TCS). Two-component systems are utilized in plant responses to hormones as well as to biotic and abiotic environmental stimuli. In plants, response regulatory genes (RRs) are one of the main members of the two-component system (TCS). METHOD: From the aspects of gene structure, evolution mode, expression type, regulatory network and gene function, the evolution process and role of RR genes in the evolution of the cotton genome were analyzed. RESULT: A total of 284 RR genes in four cotton species were identified. Including 1049 orthologous/paralogous gene pairs were identified, most of which were whole genome duplication (WGD). The RR genes promoter elements contain phytohormone responses and abiotic or biotic stress-related cis-elements. Expression analysis showed that RR genes family may be negatively regulate and involved in salt stress and drought stress in plants. Protein regulatory network analysis showed that RR family proteins are involved in regulating the DNA-binding transcription factor activity (COG5641) pathway and HP kinase pathways. VIGS analysis showed that the GhRR7 gene may be in the same regulatory pathway as GhAHP5 and GhPHYB, ultimately negatively regulating cotton drought stress by regulating POD, SOD, CAT, H2O2 and other reactive oxygen removal systems. CONCLUSION: This study is the first to gain insight into RR gene members in cotton. Our research lays the foundation for discovering the genes related to drought and salt tolerance and creating new cotton germplasm materials for drought and salt tolerance.


Assuntos
Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Filogenia , Estresse Fisiológico/genética , Genes Reguladores , Gossypium/genética , Secas , Peróxido de Hidrogênio/metabolismo
4.
Biol. Res ; 55: 4-4, 2022. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1383909

RESUMO

BACKGROUND: The internal NAD(P)H dehydrogenase (NDA) gene family was a member of the NAD(P)H dehydrogenase (ND) gene family, mainly involved in the non-phosphorylated respiratory pathways in mitochondria and played crucial roles in response to abiotic stress. METHODS: The whole genome identification, structure analysis and expression pattern of NDA gene family were conducted to analyze the NDA gene family. RESULTS: There were 51, 52, 26, and 24 NDA genes identified in G. hirsutum, G. barbadense, G. arboreum and G. raimondii, respectively. According to the structural characteristics of genes and traits of phylogenetic tree, we divided the NDA gene family into 8 clades. Gene structure analysis showed that the NDA gene family was relatively conservative. The four Gossypium species had good collinearity, and segmental duplication played an important role in the evolution of the NDA gene family. Analysis of cis-elements showed that most GhNDA genes contained cis-elements related to light response and plant hormones (ABA, MeJA and GA). The analysis of the expression patterns of GhNDA genes under different alkaline stress showed that GhNDA genes were actively involved in the response to alkaline stress, possibly through different molecular mechanisms. By analyzing the existing RNA-Seq data after alkaline stress, it was found that an NDA family gene GhNDA32 was expressed, and then theGhNDA32 was silenced by virus-induced gene silencing (VIGS). By observing the phenotype, we found that the wilting degree of silenced plants was much higher than that of the control plant after alkaline treatment, suggesting that GhNDA32 gene was involved in the response to alkaline stress. CONCLUSIONS: In this study, GhNDAs participated in response to alkaline stress, especially NaHCO3 stress. It was of great significance for the future research on the molecular mechanism of NDA gene family in responding to abiotic stresses.


Assuntos
Regulação da Expressão Gênica de Plantas , Gossypium/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Estrutura Molecular , Família Multigênica/genética , Genoma de Planta
5.
Electron J Biotechnol ; 49: 42-49, Jan. 2021. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1291646

RESUMO

BACKGROUND: Late embryogenesis abundant (LEA) proteins were reported to be related to adversity stress and drought tolerance. Lea-3 from Arachis hypogaea L. (AhLea-3) was previously found to be related to salt tolerance according to the result of transcriptome profiling and digital gene expression analysis. So, AhLea-3 was cloned and the salt tolerance was validated by transgenic peanut plants. RESULTS: AhLea-3 was isolated from M34, a salt-resistant mutant of peanut, with its cDNA as the template. AhLea-3 contains one intron and two extrons, and the full-length cDNA sequence contains 303 bp. AhLea3 was ligated to pCAMBIA1301 to obtain the overexpression vector pCAMBIA1301-AhLea-3, which was then transferred into peanut variety Huayu23. The expression level of AhLea-3, as determined by qRTPCR analysis, was >10 times higher in transgenic than in non-transgenic plants. Five days after they were irrigated with 250 mM NaCl, the transgenic plants showed less severe leaf wilting, higher activities of antioxidant enzymes (superoxide dismutase, peroxidase, and catalase), and lower malonic dialdehyde content than non-transgenic plants. Relative to non-transgenic plants, the transgenic plants had a higher photosynthetic net rate, stomatal conductance, and transpiration rate, and a lower intercellular CO2 concentration after salt stress treatment (250 mM NaCl). CONCLUSIONS: These results indicate that overexpression of AhLea-3 increased the salt tolerance of transgenic peanut plants. AhLea-3 might become a useful gene resource for the variety breeding of salinity tolerance in peanut.


Assuntos
Arachis/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal , Arachis/genética , Proteínas de Plantas/isolamento & purificação , Transformação Genética
6.
Biol. Res ; 54: 36-36, 2021. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1505821

RESUMO

BACKGROUND: Melatonin 2-hydroxylase (M2H) is the first enzyme in the catabolism pathway of melatonin, which catalyzes the production of 2-hydroxymelatonin (2-OHM) from melatonin. The content of 2-hydroxymelatonin in plants is much higher than that of melatonin. So M2H may be a key enzyme in the metabolic pathway of melatonin. METHOD: We conducted a systematic analysis of the M2H gene family in Gossypium hirsutum based on the whole genome sequence by integrating the structural characteristics, phylogenetic relationships, expression profile, and biological stress of the members of the Gossypium hirsutum M2H gene family. RESULT: We identified 265 M2H genes in the whole genome of Gossypium hirsutum, which were divided into 7 clades (clades I-VII) according to phylogenetic analysis. Most M2H members in each group had similar motif composition and gene structure characteristics. More than half of GhM2H members contain ABA-responsive elements and MeJA-responsive elements. Under different stress conditions, the expression levels of the gene changed, indicating that GhM2H members were involved in the regulation of abiotic stress. Some genes in the GhM2H family were involved in regulating melatonin levels in cotton under salt stress, and some genes were regulated by exogenous melatonin. CONCLUSION: This study is helpful to explore the function of GhM2H, the downstream metabolism gene of melatonin in cotton, and lay the foundation for better exploring the molecular mechanism of melatonin improving cotton's response to abiotic stress.


Assuntos
Gossypium/genética , Melatonina , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Família Multigênica , Regulação da Expressão Gênica de Plantas
7.
Braz. j. biol ; 79(1): 53-62, Jan.-Mar 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-984007

RESUMO

Abstract In this study, the activities of antioxidant enzymes, photosynthetic pigments, proline and carbohydrate contents in Pitcairnia encholirioides under ex vitro conditions of water deficit were evaluated. Results show that plants under progressive water stress, previously in vitro cultured in media supplemented with 30 g L-1 sucrose and GA3, accumulated more proline and increased peroxidase (POD) activity and the contents of photosynthetic pigments and carbohydrates. For plants previously in vitro cultured with 15 g L-1 sucrose and NAA, no differences were found for proline content and there were reductions in activities of peroxidase (POD), catalase (CAT) and poliphenoloxidase (PPO), and in contents of carbohydrates, with progress of ex vitro water deficit. After rehydration, plants showed physiological recovery, with enzymatic activities and contents of metabolites similar to those found in the controls not submitted to dehydration, regardless of the previous in vitro culture conditions. These results show that micropropagated P. encholirioides has high tolerance to dehydration once in ex vitro conditions, which can ensure the survival of plants from tissue culture when transferred to its natural environment, emphasizing the importance of such biotechnology for the propagation of endangered species.


Resumo Neste estudo, foram avaliadas as atividades de enzimas antioxidantes, pigmentos fotossintéticos, conteúdo de prolina e carboidratos em Pitcairnia encholirioides sob déficit hídrico em condições ex vitro. Os resultados mostraram que as plantas sob estresse hídrico progressivo, previamente cultivadas in vitro em meio de cultura suplementado com 30 g L-1 de sacarose e GA3 acumularam mais prolina e aumentaram a atividade da peroxidase (POD) e os teores de pigmentos fotossintéticos e carboidratos. Para plantas previamente cultivadas in vitro com 15 g L-1 de sacarose e ANA, não foram encontradas diferenças nos conteúdos de prolina e houve reduções nas atividades da peroxidase (POD), catalase (CAT) e polifenoloxidase (PPO), e no conteúdo de carboidratos, com o progresso do déficit hídrico ex vitro. Após a reidratação, as plantas apresentaram recuperação fisiológica, com atividades enzimáticas e conteúdo de metabólitos semelhantes aos encontrados nos controles não sujeitos à desidratação, independentemente das condições de cultivo in vitro. Estes resultados mostram que P. encholirioides micropropagada tem alta tolerância à desidratação uma vez em condições ex vitro, o que pode garantir a sobrevivência de plantas provenientes da cultura de tecidos quando transferidas para seu ambiente natural, enfatizando a importância desta biotecnologia para a propagação de espécies ameaçadas.


Assuntos
Fotossíntese/fisiologia , Prolina/metabolismo , Água/metabolismo , Bromeliaceae/fisiologia , Secas , Antioxidantes/metabolismo , Pigmentos Biológicos , Proteínas de Plantas/metabolismo , Bromeliaceae/enzimologia , Metabolismo dos Carboidratos , Longevidade
8.
Biol. Res ; 52: 14, 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1011416

RESUMO

BACKGROUND: Drought is a major abiotic stress affecting global wheat (Triticum aestivum L.) production. Exploration of drought-tolerant genes is essential for the genetic improvement of drought tolerance in wheat. Previous studies have shown that some histone encoding genes are involved in plant drought tolerance. However, whether the H2B family genes are involved in drought stress response remains unclear. METHODS: Here, we identified a wheat histone H2B family gene, TaH2B-7D, which was significantly up-regulated under drought stress conditions. Virus-induced gene silencing (VIGS) technology was used to further verify the function of TaH2B-7D in wheat drought tolerance. The phenotypic and physiological changes were examined in the TaH2B-7D knock-down plants. RESULTS: In the TaH2B-7D knock-down plants, relative electrolyte leakage rate and malonaldehyde (MDA) content significantly increased, while relative water content (RWC) and proline content significantly decreased compared with those in the non-knocked-down plants under drought stress conditions. TaH2B-7D knock-down plants exhibited severe sagging, wilting and dwarf phenotypes under drought stress conditions, but not in the non-knocked-down plants, suggesting that the former were more sensitive to drought stress. CONCLUSION: These results indicate that TaH2B-7D potentially plays a vital role in conferring drought tolerance in wheat.


Assuntos
Proteínas de Plantas/genética , Estresse Fisiológico/genética , Triticum/genética , Regulação da Expressão Gênica de Plantas/genética , Inativação Gênica , Secas , Fenótipo , Proteínas de Plantas/metabolismo , Estresse Fisiológico/fisiologia , Triticum/metabolismo , Plantas Geneticamente Modificadas/genética , Fenômenos Fisiológicos Vegetais/genética , Reação em Cadeia da Polimerase em Tempo Real
9.
Biol. Res ; 52: 56-56, 2019. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1505776

RESUMO

BACKGROUND: ADP-glucose pyrophosphorylase (AGPase), the key enzyme in plant starch biosynthesis, is a heterotetramer composed of two identical large subunits and two identical small subunits. AGPase has plastidial and cytosolic isoforms in higher plants, whereas it is mainly detected in the cytosol of grain endosperms in cereal crops. Our previous results have shown that the expression of the TaAGPL1 gene, encoding the cytosolic large subunit of wheat AGPase, temporally coincides with the rate of starch accumulation and that its overexpression dramatically increases wheat AGPase activity and the rate of starch accumulation, suggesting an important role. METHODS: In this study, we performed yeast one-hybrid screening using the promoter of the TaAGPL1 gene as bait and a wheat grain cDNA library as prey to screen out the upstream regulators of TaAGPL1 gene. And the barley stripe mosaic virus-induced gene-silencing (BSMV-VIGS) method was used to verify the functional characterization of the identified regulators in starch biosynthesis. RESULTS: Disulfide isomerase 1-2 protein (TaPDIL1-2) was screened out, and its binding to the TaAGPL1-1D promoter was further verified using another yeast one-hybrid screen. Transiently silenced wheat plants of the TaPDIL1-2 gene were obtained by using BSMV-VIGS method under field conditions. In grains of BSMV-VIGS-TaPDIL1-2-silenced wheat plants, the TaAGPL1 gene transcription levels, grain starch contents, and 1000-kernel weight also significantly increased. CONCLUSIONS: As important chaperones involved in oxidative protein folding, PDIL proteins have been reported to form hetero-dimers with some transcription factors, and thus, our results suggested that TaPDIL1-2 protein could indirectly and negatively regulate the expression of the TaAGPL1 gene and function in starch biosynthesis.


Assuntos
Proteínas de Plantas/metabolismo , Triticum/metabolismo , Pão , Genes de Plantas/genética , Regulação da Expressão Gênica de Plantas/genética , Glucose-1-Fosfato Adenililtransferase/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição , Triticum/genética , Glucose-1-Fosfato Adenililtransferase/genética
10.
Braz. j. microbiol ; 49(3): 513-521, July-Sept. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951812

RESUMO

Abstract Soil salinity is an important abiotic stress worldwide, and salt-induced oxidative stress can have detrimental effects on the biological nitrogen fixation. We hypothesized that co-inoculation of cowpea plants with Bradyrhizobium and plant growth-promoting bacteria would minimize the deleterious effects of salt stress via the induction of enzymatic and non-enzymatic antioxidative protection. To test our hypothesis, cowpea seeds were inoculated with Bradyrhizobium or co-inoculated with Bradyrhizobium and plant growth-promoting bacteria and then submitted to salt stress. Afterward, the cowpea nodules were collected, and the levels of hydrogen peroxide; lipid peroxidation; total, reduced and oxidized forms of ascorbate and glutathione; and superoxide dismutase, catalase and phenol peroxidase activities were evaluated. The sodium and potassium ion concentrations were measured in shoot samples. Cowpea plants did not present significant differences in sodium and potassium levels when grown under non-saline conditions, but sodium content was strongly increased under salt stress conditions. Under non-saline and salt stress conditions, plants co-inoculated with Bradyrhizobium and Actinomadura or co-inoculated with Bradyrhizobium and Paenibacillus graminis showed lower hydrogen peroxide content in their nodules, whereas lipid peroxidation was increased by 31% in plants that were subjected to salt stress. Furthermore, cowpea nodules co-inoculated with Bradyrhizobium and plant growth-promoting bacteria and exposed to salt stress displayed significant alterations in the total, reduced and oxidized forms of ascorbate and glutathione. Inoculation with Bradyrhizobium and plant growth-promoting bacteria induced increased superoxide dismutase, catalase and phenol peroxidase activities in the nodules of cowpea plants exposed to salt stress. The catalase activity in plants co-inoculated with Bradyrhizobium and Streptomyces was 55% greater than in plants inoculated with Bradyrhizobium alone, and this value was remarkably greater than that in the other treatments. These results reinforce the beneficial effects of plant growth-promoting bacteria on the antioxidant system that detoxifies reactive oxygen species. We concluded that the combination of Bradyrhizobium and plant growth-promoting bacteria induces positive responses for coping with salt-induced oxidative stress in cowpea nodules, mainly in plants co-inoculated with Bradyrhizobium and P. graminis or co-inoculated with Bradyrhizobium and Bacillus.


Assuntos
Cloreto de Sódio/metabolismo , Bradyrhizobium/fisiologia , Inoculantes Agrícolas/fisiologia , Vigna/microbiologia , Antioxidantes/metabolismo , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Superóxido Dismutase/metabolismo , Peroxidação de Lipídeos , Catalase/metabolismo , Peroxidase/metabolismo , Estresse Oxidativo , Salinidade , Vigna/crescimento & desenvolvimento , Vigna/metabolismo , Glutationa/metabolismo
11.
Braz. j. biol ; 77(4): 774-780, Nov. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-888804

RESUMO

Abstract During germination, orthodox seeds become gradually intolerant to desiccation, and for this reason, they are a good model for recalcitrance studies. In the present work, physiological, biochemical, and ultrastructural aspects of the desiccation tolerance were characterized during the germination process of Anadenanthera colubrina seeds. The seeds were imbibed during zero (control), 2, 8, 12 (no germinated seeds), and 18 hours (germinated seeds with 1 mm protruded radicle); then they were dried for 72 hours, rehydrated and evaluated for survivorship. Along the imbibition, cytometric and ultrastructural analysis were performed, besides the extraction of the heat-stable proteins. Posteriorly to imbibition and drying, the evaluation of ultrastructural damages was performed. Desiccation tolerance was fully lost after root protrusion. There was no increase in 4C DNA content after the loss of desiccation tolerance. Ultrastructural characteristics of cells from 1mm roots resembled those found in the recalcitrant seeds, in both hydrated and dehydrated states. The loss of desiccation tolerance coincided with the reduction of heat-stable proteins.


Resumo Durante a germinação, sementes ortodoxas tornam-se gradualmente intolerantes à dessecação, e por isso podem ser utilizadas como modelo para o estudo da recalcitrância. No presente trabalho realizou-se uma caracterização dos aspectos fisiológicos, bioquímicos e ultraestruturais da perda da tolerância à dessecação de sementes de Anadenanthera colubrina em processo germinativo. Para isso as sementes foram embebidas durante 0 (controle), 2,8,12 e aproximadamente 18 horas (sementes germinadas com 1 mm de radícula), secas por 72 horas, reidratadas e a sobrevivência avaliada. Ao longo da embebição foram realizadas análises citométricas, ultraestruturais e extração de proteínas resistentes ao calor e após embebição e secagem foram avaliados danos ultraestruturais. A tolerância à dessecação foi totalmente perdida após a protrusão radicular. Não houve aumento do conteúdo de DNA 4C quando a tolerância à dessecação foi perdida. Características ultraestruturais de células de radículas de 1 mm assemelharam-se às encontradas em sementes recalcitrantes tanto no estado hidratado quanto desidratado. A perda da tolerância à dessecação coincidiu com a redução do conteúdo de proteínas resistentes ao calor.


Assuntos
Germinação , Dessecação , Fabaceae/fisiologia , Proteínas de Plantas/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Sementes/genética , Sementes/ultraestrutura , Árvores/crescimento & desenvolvimento , Árvores/fisiologia , Árvores/genética , Árvores/ultraestrutura , Fabaceae/crescimento & desenvolvimento , Fabaceae/genética , Fabaceae/ultraestrutura
12.
Braz. j. microbiol ; 48(3): 537-543, July-Sept. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-889126

RESUMO

Abstract Metallothioneins are a superfamily of low-molecular-weight, cysteine (Cys)-rich proteins that are believed to play important roles in protection against metal toxicity and oxidative stress. The main purpose of this study was to investigate the effect of heterologous expression of a rice metallothionein isoform (OsMTI-1b) on the tolerance of Saccharomyces cerevisiae to Cd2+, H2O2 and ethanol stress. The gene encoding OsMTI-1b was cloned into p426GPD as a yeast expression vector. The new construct was transformed to competent cells of S. cerevisiae. After verification of heterologous expression of OsMTI-1b, the new strain and control were grown under stress conditions. In comparison to control strain, the transformed S. cerevisiae cells expressing OsMTI-1b showed more tolerance to Cd2+ and accumulated more Cd2+ ions when they were grown in the medium containing CdCl2. In addition, the heterologous expression of GST-OsMTI-1b conferred H2O2 and ethanol tolerance to S. cerevisiae cells. The results indicate that heterologous expression of plant MT isoforms can enhance the tolerance of S. cerevisiae to multiple stresses.


Assuntos
Proteínas de Plantas/genética , Oryza/genética , Saccharomyces cerevisiae/metabolismo , Cádmio/metabolismo , Expressão Gênica , Etanol/metabolismo , Peróxido de Hidrogênio/metabolismo , Metalotioneína/genética , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/genética , Estresse Oxidativo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Metalotioneína/metabolismo
13.
Braz. j. biol ; 77(3): 535-541, July-Sept. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-888779

RESUMO

Abstract Golden trumpet, Tabebuia chrysotricha, is a native tree from the Brazilian Atlantic rain forest, with a broad latitudinal distribution. In this study, we investigated the potential effects of short-term changes in micro-weather conditions on structural features, and total protein and carbohydrate content of golden trumpet leaves, using structural and histochemical approaches. Leaves were harvested in four different micro-weather conditions: 1. Afternoon, after a hot, sunny day; 2. at dawn, after a previously hot, sunny day; 3. at noon, of a hot, sunny day; and 4. at noon, of a cold, cloudy day. Leaflets exposed to low light irradiance showed flattened chloroplasts, uniformly distributed within the cells, throughout the palisade parenchyma. Conversely, leaflets exposed to high light irradiance presented flattened and rounded chloroplasts, in the upper and lower palisade parenchyma cells, respectively. The strongest protein staining was found for leaves harvested at the coldest period, whereas the weakest protein staining was found for leaves harvested after a hot, sunny day. The largest and most numerous starch grains were found for leaves harvested in the afternoon, after a hot, sunny day. Conversely, the smallest and less numerous starch grains were found for leaves harvested at dawn. Analysis of the data reported herein suggests that the leaflet responses to transient changes in micro-weather conditions are likely to contribute to the golden trumpet successful establishment in the broad latitudinal distribution in which the species is found.


Resumo Ipê amarelo é uma árvore nativa da floresta Atlântica brasileira, encontrada em uma ampla distribuição latitudinal. Neste estudo, nós investigamos os efeitos potenciais de alterações de curto prazo nas condições micro-climáticas sobre características estruturais, proteína e carboidratos histoquimicamente marcados, de folhas de ipê amarelo, usando estratégias de análise estrutural e histoquímicas. As folhas foram marcadas em quatro condições microclimáticas distintas: 1. Tarde, após um dia quente e ensolarado; 2. Amanhecer, após um dia quente e ensolarado; 3. Ao meio-dia, de um dia quente e ensolarado; e 4. Ao meio-dia, de um dia frio e nublado. Folíolos expostos à baixa irradiância luminosa apresentaram cloroplastos achatados, uniformemente distribuídos no interior das células, por todo o parênquima paliçádico, enquanto que folíolos expostos à alta irradiância apresentaram cloroplastos achatados e arredondados, nas células superiores e inferiores do parênquima paliçádico, respectivamente. A marcação mais intensa para proteína foi observada para folhas coletadas no momento mais frio de coleta, enquanto que a marcação mais fraca foi observada para folhas coletadas após um dia quente e ensolarado. Os grãos de amido maiores e mais numerosos foram observados em folhas coletadas durante a tarde de dia quente e ensolarado, enquanto que os menores e menos numerosos grãos de amido foram observados em folhas coletadas ao amanhecer.


Assuntos
Proteínas de Plantas/metabolismo , Tempo (Meteorologia) , Folhas de Planta/metabolismo , Tabebuia/anatomia & histologia , Tabebuia/metabolismo , Metabolismo dos Carboidratos , Brasil , Cloroplastos/metabolismo , Floresta Úmida , Microclima
14.
Electron. j. biotechnol ; 26: 12-19, Mar. 2017. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1009164

RESUMO

Background: Expansins play an important role in cell wall metabolism and fruit softening. Determination of expansin activity is a challenging problem since it depends on measuring cell wall properties by using ad hoc extensometers, a fact that has strongly restricted its study. Then, the objective of the work was to adapt a methodology to measure cell wall creep and expansin activity using a commercial texture meter, equipped with miniature tensile grips and an ad hoc cuvette of easy construction. Results: It was possible to measure hypocotyls acid growth and expansin activity in a reliable and reproducible way, using a commercial texture meter, common equipment found in laboratories of food science or postharvest technology. Expansin activity was detected in protein extracts from cucumber hypocotyls, tomato and strawberry fruits, and statistical differences in expansin activity were found in both fruit models at different ripening stages. Conclusions: The possibility of measuring expansin activity following this adapted protocol with a commercial texture meter could contribute to ease and increase the analysis of expansin in different systems, leading to a better understanding of the properties of these proteins under different experimental conditions.


Assuntos
Proteínas de Plantas/metabolismo , Solanum lycopersicum/metabolismo , Cucumis sativus/metabolismo , Fragaria/metabolismo , Proteínas de Plantas/análise , Parede Celular/metabolismo , Hipocótilo/crescimento & desenvolvimento , Elasticidade , Frutas/metabolismo
15.
Electron. j. biotechnol ; 19(4): 44-51, July 2016. ilus
Artigo em Inglês | LILACS | ID: lil-793952

RESUMO

Background: The acidic subunit of amarantin (AAC)-the predominant amaranth seed storage protein-has functional potential and its third variable region (VR) has been modified with antihypertensive peptides to improve this potential. Here, we modified the C-terminal in the fourth VR of AAC by inserting four VY antihypertensive peptides. This modified protein (AACM.4) was expressed in Escherichia coli. In addition, we also recombinantly expressed other derivatives of the amarantin protein. These include: unmodified amarantin acidic subunit (AAC); amarantin acidic subunit modified at the third VR with four VY peptides (AACM.3); and amarantin acidic subunit doubly modified, in the third VR with four VY peptides and in the fourth VR with the RIPP peptide (AACM.3.4). Results: E. coli BL21-CodonPlus (DE3)-RIL was the most favorable strain for the expression of proteins. After 6 h of induction, it showed the best recombinant protein titer. The AAC and AACM.4 were obtained at higher titers (0.56 g/L) while proteins modified in the third VR showed lower titers: 0.44 g/L and 0.33 g/L for AACM.3 and AACM.3.4, respectively. As these AAC variants were mostly expressed in an insoluble form, we applied a refolding protocol. This made it possible to obtain all proteins in soluble form. Modification of the VR 4 improves the thermal stability of amarantin acidic subunit; AAC manifested melting temperature (Tm) at 34°C and AACM.4 at 37.2°C. The AACM.3 and AACM.3.4 did not show transition curves. Conclusions: Modifications to the third VR affect the thermal stability of amarantin acidic subunit.


Assuntos
Proteínas de Plantas/metabolismo , Amaranthus , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/química , Temperatura , Engenharia de Proteínas , Western Blotting , Reatores Biológicos , Subunidades Proteicas , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Estabilidade Proteica , Fermentação , Globulinas
16.
Mem. Inst. Oswaldo Cruz ; 110(1): 114-124, 03/02/2015. tab
Artigo em Inglês | LILACS | ID: lil-741621

RESUMO

This paper presents, from the perspective of technological development and production, the results of an investigation examining 61 clinical studies with vaccines conducted in Brazil between 1938-2013, with the participation of the Oswaldo Cruz Institute (IOC) and the Oswaldo Cruz Foundation (Fiocruz). These studies have been identified and reviewed according to criteria, such as the kind of vaccine (viral, bacterial, parasitic), their rationale, design and methodological strategies. The results indicate that IOC and Fiocruz have accumulated along this time significant knowledge and experience for the performance of studies in all clinical phases and are prepared for the development of new vaccines products and processes. We recommend national policy strategies to overcome existing regulatory and financing constraints.


Assuntos
Animais , Ração Animal/efeitos adversos , Proteínas Alimentares/química , Modelos Biológicos , Proantocianidinas/química , Rúmen/metabolismo , Brassica rapa/química , Precipitação Química , Proteínas Alimentares/metabolismo , Fermentação , Fabaceae/efeitos adversos , Fabaceae/química , Frutas/efeitos adversos , Frutas/química , Estrutura Molecular , Peso Molecular , Concentração Osmolar , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Proantocianidinas/efeitos adversos , Proantocianidinas/metabolismo , Ruminantes , Ribulose-Bifosfato Carboxilase/química , Ribulose-Bifosfato Carboxilase/metabolismo , Rúmen/microbiologia , Solubilidade , Estereoisomerismo , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo
17.
Ciênc. Saúde Colet. (Impr.) ; 20(2): 449-460, fev. 2015. tab
Artigo em Português | LILACS | ID: lil-742218

RESUMO

O objetivo deste trabalho foi analisar os motivos das faltas às consultas odontológicas em Unidades de Saúde da Família (USF) e implementar estratégias para sua redução por meio da pesquisa-ação. O estudo foi realizado em 12 USF de Piracicaba/SP, de 01 de janeiro a 31 de dezembro de 2010. A amostra se consistiu de 385 usuários, entrevistados por telefone, sobre os motivos das faltas, além de 12 cirurgiões-dentistas e 12 enfermeiras. Realizaram-se duas oficinas com os profissionais: uma para problematização dos dados coletados nas entrevistas e elaboração de estratégias; e outra após 4 meses, para avaliação. O maior motivo de faltas foi a coincidência do horário de funcionamento das unidades com o de trabalho dos usuários. Dentre as estratégias ressaltou-se a realização de palestras sobre saúde bucal, educação permanente nas reuniões de equipe, capacitação dos Agentes Comunitários de Saúde, participação em grupos terapêuticos e parcerias entre Equipe de Saúde Bucal e equipamentos sociais da comunidade. A adoção de prontuário único foi a estratégia desafiadora encontrada pelos profissionais. Concluiu-se que as estratégias implementadas levaram à diminuição das faltas em 66,6% e o caráter motivador das oficinas possibilitou a reflexão crítica para o redirecionamento da prática em saúde.


The aim of this study was to analyze the reasons for missed appointments in dental Family Health Units (FHU) and implement strategies to reduce same through action research. This is a study conducted in 12 FHUs in Piracicaba in the State of São Paulo from January, 1 to December, 31 2010. The sample was composed of 385 users of these health units who were interviewed over the phone and asked about the reasons for missing dental appointments, as well as 12 dentists and 12 nurses. Two workshops were staged with professionals: the first to assess the data collected in interviews and develop strategy, and the second for evaluation after 4 months. The primary cause for missed appointments was the opening hours of the units coinciding with the work schedule of the users. Among the strategies suggested were lectures on oral health, ongoing education in team meetings, training of Community Health Agents, participation in therapeutic groups and partnerships between Oral Health Teams and the social infrastructure of the community. The adoption of the single medical record was the strategy proposed by professionals. The strategies implemented led to a 66.6% reduction in missed appointments by the units and the motivating nature of the workshops elicited critical reflection to redirect health practices.


Assuntos
Cisteína Endopeptidases/metabolismo , Precursores Enzimáticos/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Biocatálise , Simulação por Computador , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Ativação Enzimática , Precursores Enzimáticos/antagonistas & inibidores , Precursores Enzimáticos/química , Precursores Enzimáticos/genética , Temperatura Alta , Concentração de Íons de Hidrogênio , Hidrólise , Isoenzimas/antagonistas & inibidores , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Cinética , Leucina/análogos & derivados , Leucina/química , Leucina/metabolismo , Leucina/farmacologia , Modelos Moleculares , Dados de Sequência Molecular , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/química , Proteínas de Plantas/genética , Conformação Proteica , Dobramento de Proteína , Estabilidade Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
18.
Electron. j. biotechnol ; 17(6): 287-295, Nov. 2014. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-730260

RESUMO

Background Abscisic acid (ABA)-, stress- and ripening-induced protein (ASR) is plant-specific hydrophilic transcriptional regulators involved in sucrose stress and wounding in banana. However, it is not known whether banana ASR genes confer salt stress tolerance. The contexts of the study was to analysis the sequence characterization of banana ASR1, and identify its expression patterns and function under salt stress using quantitative real-time PCR (qPCR) and overexpression in Arabidopsis. The purpose was to evaluate the role of banana ASR1 to salt stress tolerance employed by plants. Results A full-length cDNA isolated from banana fruit was named MaASR1, and it had a 432 bp open reading frame (ORF) encoding 143 amino acids. MaASR1 was preferential expression in roots and leaves compared to low expression in fruits, rhizomes and flowers. Under salt stress, the expression of MaASR1 quickly increased and highest expression level was detected in roots and leaves at 4 h, and then gradually decreased. These results suggested that MaASR1 expression was induced under salt stress. MaASR1 protein was localized in the nucleus and plasma membrane. MaASR1 was transformed to Arabidopsis and verified by southern and northern analysis, transgenic lines L14 and L38 integrated one and two copies of MaASR1, respectively, while overexpression in transgenic lines provided evidence for the role of MaASR1 to salt stress tolerance. Conclusions This study demonstrated that overexpression of MaASR1 in Arabidopsis confers salt stress tolerance by reducing the expression of ABA/stress-responsive genes, but does not affect the expression of the ABA-independent pathway and biosynthesis pathway genes.


Assuntos
Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Musa/genética , Tolerância ao Sal , Reguladores de Crescimento de Plantas , RNA/análise , Plantas Geneticamente Modificadas , Clonagem Molecular , Análise de Sequência , Arabidopsis , Ácido Abscísico , DNA Complementar/síntese química , Reação em Cadeia da Polimerase em Tempo Real , Estresse Salino
20.
Rev. salud pública ; 16(3): 361-370, 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-729647

RESUMO

Objetivo Visando conhecer o impacto das demandas judiciais sobre a organização dos serviços públicos de saúde, realizou-se uma revisáo sistemática com enfoque na "judicialização da saúde" para fornecimento de medicamentos. Métodos Foram analisados artigos originais publicados no período de 2007 a 2011, na literatura nacional e internacional, resultando no total de 49239 artigos disponíveis nas bases de dados Science Direct e BIREME. Resultados A pesquisa indicou predominância da bibliografia proveniente do Brasil, principalmente do sudeste, bem como de estudo realizado na Colômbia. Discursáo Dentre os pleitos, configuraram-se como principais agravos relatados as doenças crônicas, podendo-se citar: diabetes, hipertensáo, cânceres e artrite reumatóide. Por serem afecções parte de programas específicos do Sistema Único de Saúde, a dificuldade de acesso a esses fármacos e consequente judicialização da saúde demonstrou a fragilidade das políticas públicas existentes. Conclusão Por fim, conclui-se que a via judicial, apesar de ser uma estratégia para garantir o acesso ao medicamento, apresenta inabilidade para lidar com o julgamento das ações e gera, dessa forma, distorções no fluxo dos sistemas públicos.


Objective A systematic review, focusing on the judicialisation of health regarding gaining access to medicines, was aimed at understanding the impact of lawsuits on the organisation of public health services. Method Original articles published between 2007 and 2011 in the pertinent national and international literature were analysed, resulting in 49,239 articles being found in Science Direct and BIREME databases. Results The survey indicated a predominance of literature from Brazil, mainly the southeast, as well as a study from Colombia. Discussion The aforementioned chronic disease-related claims involved diabetes, high blood pressure, cancer and rheumatoid arthritis. Forming part of specific Unified Healthcare System programmes highlighted the difficulty in gaining access to the appropriate medicine and consequent health judicialisation demonstrated the fragility of existing public policy. Conclusion It was concluded that the courts (despite being a strategy for ensuring access to medicine) were unable to deal with the current spate of lawsuits, thereby leading to disruption regarding the flow of public systems.


Objetivo El estudio tiene como objetivo evaluar el impacto de las demandas judiciales sobre la organización de los servicios públicos de salud, mediante la realización de una revisión sistemática centrada en el uso de los tribunales para el suministro de medicamentos. Método Fueron identificados 49239 artículos en las bases de datos Science Direct e BIREME. Resultado El estudio indicó que la mayor parte de la bibliografía es de Brasil, con uno estudio en Colombia. Discusión Aparecen como los principales trastornos de salud relatados a las enfermedades crónicas, se pueden citar: la diabetes, la hipertensión, el cáncer y la artritis reumatoide. Debido a que son parte de los programas específicos de lo sistema de salud, la dificultad de acceso a estos fármacos y la consiguiente judicialización de la salud de manifiesto la fragilidad de las políticas públicas existentes. Conclusiones Por último, está la conclusión de que los tribunales, a pesar de ser una estrategia para garantizar el acceso a la medicina, presenta incapacidad para hacer frente al juicio de las acciones y por lo tanto genera distorsiones en el flujo de los sistemas públicos.


Assuntos
Ácido Aspártico Endopeptidases/genética , Cacau/enzimologia , Leucina/análogos & derivados , Sementes/enzimologia , Sequência de Aminoácidos , Ácido Aspártico Endopeptidases/efeitos dos fármacos , Ácido Aspártico Endopeptidases/metabolismo , Cacau/genética , Clonagem Molecular , Cumarínicos/farmacologia , DNA Complementar/química , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Concentração de Íons de Hidrogênio , Isoenzimas/efeitos dos fármacos , Isoenzimas/genética , Isoenzimas/metabolismo , Leucina/farmacologia , Dados de Sequência Molecular , Pepstatinas/farmacologia , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sementes/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Yarrowia/genética , Yarrowia/metabolismo
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