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Pesquisa : G05.360.340.024.340.364.500 [Categoria DeCS]
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Id: biblio-839379
Autor: Liu, Tianxiang; Li, Huiru; Ding, Yatong; Qi, Yuancheng; Gao, Yuqian; Song, Andong; Shen, Jinwen; Qiu, Liyou.
Título: Genome-wide gene expression patterns in dikaryon of the basidiomycete fungus Pleurotus ostreatus
Fonte: Braz. j. microbiol;48(2):380-390, April.-June 2017. tab, graf.
Idioma: en.
Projeto: Natural Science Foundation of Henan Province; . Innovative Research Team.
Resumo: Abstract Dikarya is a subkingdom of fungi that includes Ascomycota and Basidiomycota. The gene expression patterns of dikaryon are poorly understood. In this study, we bred a dikaryon DK13 × 3 by mating monokaryons MK13 and MK3, which were from the basidiospores of Pleurotus ostreatus TD300. Using RNA-Seq, we obtained the transcriptomes of the three strains. We found that the total transcript numbers in the transcriptomes of the three strains were all more than ten thousand, and the expression profile in DK13 × 3 was more similar to MK13 than MK3. However, the genes involved in macromolecule utilization, cellular material synthesis, stress-resistance and signal transduction were much more up-regulated in the dikaryon than its constituent monokaryons. All possible modes of differential gene expression, when compared to constituent monokaryons, including the presence/absence variation, and additivity/nonadditivity gene expression in the dikaryon may contribute to heterosis. By sequencing the urease gene poure sequences and mRNA sequences, we identified the monoallelic expression of the poure gene in the dikaryon, and its transcript was from the parental monokaryon MK13. Furthermore, we discovered RNA editing in the poure gene mRNA of the three strains. These results suggest that the gene expression patterns in dikaryons should be similar to that of diploids during vegetative growth.
Descritores: Pleurotus/genética
Perfilação da Expressão Gênica
-Alelos
Genes Fúngicos
Responsável: BR1.1 - BIREME


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Id: lil-777368
Autor: Silva, Danielly Beraldo dos Santos; Rodrigues, Luana Mireli Carbonera; Almeida, Adriana Araújo de; Oliveira, Kelly Mari Pires de; Grisolia/, Alexéia Barufatti.
Título: Novel point mutations in the ERG11 gene in clinical isolates of azole resistant Candida species
Fonte: Mem. Inst. Oswaldo Cruz;111(3):192-199, Mar. 2016. tab, graf.
Idioma: en.
Resumo: The azoles are the class of medications most commonly used to fight infections caused by Candida sp. Typically, resistance can be attributed to mutations in ERG11 gene (CYP51) which encodes the cytochrome P450 14α-demethylase, the primary target for the activity of azoles. The objective of this study was to identify mutations in the coding region of theERG11 gene in clinical isolates of Candidaspecies known to be resistant to azoles. We identified three new synonymous mutations in the ERG11 gene in the isolates of Candida glabrata (C108G, C423T and A1581G) and two new nonsynonymous mutations in the isolates of Candida krusei - A497C (Y166S) and G1570A (G524R). The functional consequence of these nonsynonymous mutations was predicted using evolutionary conservation scores. The G524R mutation did not have effect on 14α-demethylase functionality, while the Y166S mutation was found to affect the enzyme. This observation suggests a possible link between the mutation and dose-dependent sensitivity to voriconazole in the clinical isolate of C. krusei. Although the presence of the Y166S in phenotype of reduced azole sensitivity observed in isolate C. kruseidemands investigation, it might contribute to the search of new therapeutic agents against resistant Candida isolates.
Descritores: Candida/efeitos dos fármacos
Candida/genética
Farmacorresistência Fúngica/genética
Mutação Puntual/efeitos dos fármacos
/genética
STEROL CONGENITAL ABNORMALITIES-DEMETHYLASE/genética
-Antifúngicos/farmacologia
Azóis/farmacologia
Candida glabrata/genética
Candida/classificação
Candida/isolamento & purificação
Relação Dose-Resposta a Droga
Genes Fúngicos
Haplótipos/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Filogenia
Voriconazol/farmacologia
Limites: Humanos
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Id: lil-775129
Autor: Chen, Chun; Xie, Tingna; Ye, Sudan; Jensen, Annette Bruun; Eilenberg, J ørgen.
Título: Selection of reference genes for expression analysis in the entomophthoralean fungus Pandora neoaphidis
Fonte: Braz. j. microbiol;47(1):259-265, Jan.-Mar. 2016. tab, graf.
Idioma: en.
Projeto: Natural Science Foundation of China; . International Foundation for Science; . Science and Technology Planning Project of Zhejiang Province; . Zhejiang Natural Science Foundation.
Resumo: Abstract The selection of suitable reference genes is crucial for accurate quantification of gene expression and can add to our understanding of host–pathogen interactions. To identify suitable reference genes in Pandora neoaphidis, an obligate aphid pathogenic fungus, the expression of three traditional candidate genes including 18S rRNA(18S), 28S rRNA(28S) and elongation factor 1 alpha-like protein (EF1), were measured by quantitative polymerase chain reaction at different developmental stages (conidia, conidia with germ tubes, short hyphae and elongated hyphae), and under different nutritional conditions. We calculated the expression stability of candidate reference genes using four algorithms including geNorm, NormFinder, BestKeeper and Delta Ct. The analysis results revealed that the comprehensive ranking of candidate reference genes from the most stable to the least stable was 18S (1.189), 28S (1.414) and EF1 (3). The 18S was, therefore, the most suitable reference gene for real-time RT-PCR analysis of gene expression under all conditions. These results will support further studies on gene expression in P. neoaphidis.
Descritores: Entomophthorales/genética
Genes Fúngicos
Perfilação da Expressão Gênica/métodos
Perfilação da Expressão Gênica/normas
Padrões de Referência
Reação em Cadeia da Polimerase em Tempo Real/métodos
Reação em Cadeia da Polimerase em Tempo Real/normas
-Fator 1 de Elongação de Peptídeos/genética
/genética
RNA, RIBOSOMAL, 1ABDOMINAL NEOPLASMSS/genética
/genética
RNA, RIBOSOMAL, ABORTION, HABITUALS/genética
Responsável: BR1.1 - BIREME


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Id: lil-755832
Autor: Singh, Diwakar; Radhakrishnan, T.; Kumar, Vinod; Bagwan, N.B.; Basu, M.S.; Dobaria, J.R.; Mishra, Gyan P.; Chanda, S.V..
Título: Molecular characterisation of Aspergillus flavus isolates from peanut fields in India using AFLP
Fonte: Braz. j. microbiol;46(3):673-682, July-Sept. 2015. tab, ilus.
Idioma: en.
Resumo:

Aflatoxin contamination of peanut, due to infection by Aspergillus flavus, is a major problem of rain-fed agriculture in India. In the present study, molecular characterisation of 187 Aspergillus flavus isolates, which were sampled from the peanut fields of Gujarat state in India, was performed using AFLP markers. On a pooled cluster analysis, the markers could successfully discriminate among the ‘A’, ‘B’ and ‘G’ group A. flavus isolates. PCoA analysis also showed equivalent results to the cluster analysis. Most of the isolates from one district could be clustered together, which indicated genetic similarity among the isolates. Further, a lot of genetic variability was observed within a district and within a group. The results of AMOVA test revealed that the variance within a population (84%) was more than that between two populations (16%). The isolates, when tested by indirect competitive ELISA, showed about 68.5% of them to be atoxigenic. Composite analysis between the aflatoxin production and AFLP data was found to be ineffective in separating the isolate types by aflatoxigenicity. Certain unique fragments, with respect to individual isolates, were also identified that may be used for development of SCAR marker to aid in rapid and precise identification of isolates.

.
Descritores: Aspergillus flavus
Aflatoxinas/metabolismo
Arachis/microbiologia
-Agricultura
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados
Aspergillus flavus/classificação
Aspergillus flavus/genética
Aspergillus flavus/isolamento & purificação
DNA Fúngico/genética
Ensaio de Imunoadsorção Enzimática
Genes Fúngicos
Variação Genética/genética
Índia
Tipagem Molecular
Técnicas de Tipagem Micológica
Análise de Componente Principal
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Id: lil-730266
Autor: Fuentes, Marisol; Hermosilla, Germán; Alburquenque, Claudio; Falconer, Mary A; Amaro, José; Tapia, Cecilia.
Título: Caracterización de los mecanismos de resistencia a azoles en aislados clínicos chilenos de Candida albicans / Characterization of azole resistance mechanisms in Chilean clinical isolates of Candida albicans
Fonte: Rev. chil. infectol;31(5):511-517, oct. 2014. ilus, graf, tab.
Idioma: es.
Projeto: Fondecyt; . UCH.
Resumo: Introduction: The commensal yeast Candida albicans, can cause superficial or systemic candidiasis in susceptible hosts. In Chile, azole antifungals are the most widely used drugs in the treatment of candidiasis. In a previous study performed at our center, 2.1 and 1.6% of clinical isolates of C. albicans were found to be resistant to fluconazole and voriconazole, respectively. Objective: To characterize the resistance mechanisms involved in azoles resistance in Chilean clinical isolates. Methodology: Eight resistant, nine susceptible-dose dependent (SDD) and 10 susceptible strains (n: 27) were selected according to the Clinical Laboratory Standards Institute (CLSI) M27-S3 criteria, from vaginal and urine samples. Mutations in the 408-488 region of the ERG11 gene were studied by sequencing, and the relative expression of ERG11 gene and efflux pump genes CDR1, CDR2 and MDR1, was evaluated by quantitative real-time PCR (q-PCR). Results: No mutations were detected in the ERG11 gene and its overexpression was found only in 12.5% of the resistant strains (1/8). The most prevalent mechanism of resistance was the over-expression of efflux pumps (62.5%; 5/8). Conclusion: The study of the expression of efflux pumps by q-PCR could be a useful diagnostic tool for early detection of azole resistance in C. albicans.

Introducción: Candida albicans es una levadura comensal capaz de causar una infección oportunista en hospederos susceptibles denominada candidiasis, que puede ser superficial o sistémica. En Chile, los antifúngicos más utilizados para el tratamiento de las candidiasis son los azoles. En un estudio previo en nuestro centro, se detectó que 2,1 y 1,6% de cepas clínicas de C. albicans fueron resistentes a fluconazol y voriconazol, respectivamente. Objetivo: Caracterizar los mecanismos de resistencia involucrados en la resistencia a azoles en cepas clínicas chilenas. Metodología: Según los criterios del Clinical Laboratory Standards Institute (CLSI) M27-S3, se seleccionaron ocho cepas resistentes, nueve cepas susceptibles dosis dependiente (SDD) y 10 cepas sensibles (n: 27), aisladas de flujo vaginal y orina. Se evaluó la presencia de mutaciones en la región 408-488 del gen ERG11 por secuenciación y la expresión relativa del gen ERG11 y de los genes de bombas de eflujo CDR1, CDR2 y MDR1 por RPC en tiempo real cuantitativa (q-PCR). Resultados: No se encontraron mutaciones en el gen ERG11 y la sobre-expresión de éste sólo se presentó en 12,5% de las cepas resistentes (1/8). El mecanismo prevalente en la cepas resistentes fue la sobre-expresión de bombas de eflujo encontrándose en 62,5% de las cepas resistentes (5/8). Conclusión: El estudio de la expresión bombas de eflujo por q-PCR podría ser una herramienta diagnóstica útil para la detección temprana de resistencia a azoles en C. albicans.
Descritores: Antifúngicos/farmacologia
Candida albicans/efeitos dos fármacos
Fluconazol/farmacologia
Voriconazol/farmacologia
-Chile
Candida albicans/genética
Candida albicans/isolamento & purificação
Farmacorresistência Fúngica
Regulação Fúngica da Expressão Gênica
Genes Fúngicos/genética
Reação em Cadeia da Polimerase em Tempo Real
RNA Fúngico/genética
Limites: Feminino
Humanos
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: CL1.1 - Biblioteca Central


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Id: lil-727007
Autor: Paula, Daphine Ariadne Jesus de; Silva, Lívia Kmetzsch Rosa e; Staats, Charley Christian; Vainstein, Marilene H.; Joanoni, Ana Lúcia Pinto; Nakazato, Luciano; Dutra, Valéria.
Título: Identification of genes expressed by Cryptococcus gattii during iron deprivation
Fonte: Braz. j. microbiol;45(3):813-820, July-Sept. 2014. tab.
Idioma: en.
Resumo: Cryptococcus neoformans and C. gattii are pathogenic yeasts that cause life-threatening diseases in humans and animals. Iron is an essential nutrient for virtually every organism as it functions as a cofactor in numerous essential enzymatic reactions. In the literature, the competition for iron between microbes and mammalian hosts during infection is well documented. In this study, we used representational difference analysis (RDA) in order to gain a better understanding of how C. gattii responds to iron starvation. A total of 15 and 29 genes were identified as having altered expression levels due to iron depletion after 3 h and 12 h, respectively. Of these, eight genes were identified in both libraries. The transcripts were related to many biological processes, such as cell cycle, ergosterol metabolism, cell wall organization, transportation, translation, cell respiration and the stress response. These data suggest a remodeling of C. gattii metabolism during conditions of iron deprivation.
Descritores: Cryptococcus gattii/genética
Cryptococcus gattii/metabolismo
Perfilação da Expressão Gênica
Ferro/metabolismo
Estresse Fisiológico
-Cryptococcus gattii/fisiologia
Genes Fúngicos
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Id: lil-723099
Autor: Samadlouie, Hamid-Reza; Hamidi-Esfahani, Zohreh; Alavi, Seyed-Mehdi; Varastegani, Boshra.
Título: Expression analysis for genes involved in arachidonic acid biosynthesis in Mortierella alpina CBS 754.68
Fonte: Braz. j. microbiol;45(2):439-445, Apr.-June 2014. graf, tab.
Idioma: en.
Resumo: The time courses for production of fungal biomass, lipid, phenolic and arachidonic acid (ARA) as well as expression of the genes involved in biosynthesis of ARA and lipid were examined in Mortierella alpina CBS 754.68. A significant increase in the arachidonic acid content in lipids that coincided with reduced levels of lipid was obtained. Reduced gene expression occurred presumably due to the steady reduction of carbon and nitrogen resources. However, these energy resources were inefficiently compensated by the breakdown of the accumulated lipids that in turn, induced up-regulated expression of the candidate genes. The results further indicated that the expression of the GLELO encoding gene is a rate-limiting step in the biosynthesis of ARA in the early growth phase.
Descritores: Ácido Araquidônico/biossíntese
Vias Biossintéticas/genética
Perfilação da Expressão Gênica
Mortierella/genética
Mortierella/metabolismo
-Carbono/metabolismo
Genes Fúngicos
Nitrogênio/metabolismo
Reação em Cadeia da Polimerase em Tempo Real
Responsável: BR1.1 - BIREME


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Id: lil-676905
Autor: Gontia-Mishra, Iti; Deshmukh, Dhanshree; Tripathi, Niraj; Bardiya-Bhurat, Khushboo; Tantwai, Keerti; Tiwari, Sharad.
Título: Isolation, morphological and molecular characterization of phytate-hydrolysing fungi by 18S rDNA sequence analysis
Fonte: Braz. j. microbiol;44(1):317-323, 2013. ilus.
Idioma: en.
Resumo: Phytate is the primary storage form of phosphate in plants. Monogastric animals like poultry, pigs and fishes have very low or no phytase activities in their digestive tracts therefore, are incapable to efficiently utilize phytate phosphorus from the feed. Phytase from microbial sources are supplemented to feedstuff of these to increase the uptake of phytate phosphorus. In the present work efforts were made to isolate and characterize proficient phytase producing fungi from soil. Phytase producing fungi were isolated using phytate specific medium. Fungal isolates were selected according to their higher phytase activities. These isolates were further characterized and identified by morphological and microscopic analysis and confirmed by amplification of 18S rRNA gene, using specific primers. This gene was subsequently sequenced and phylogenetic affiliations were assigned. Fungal isolates were identified as various species of Aspergillus. Phytases from these fungi could be utilized as a feed additive in poultry and swine industries.
Descritores: Ácido Fítico/análise
Aspergillus/genética
Aspergillus/isolamento & purificação
Grão Comestível/enzimologia
Grão Comestível/genética
Fosfatos/análise
Genes Fúngicos
Íons Pesados
Inositol
-Amostras de Alimentos
Hidrólise
Métodos
Tipo de Publ: Estudo Comparativo
Responsável: BR32.1 - Serviço de Biblioteca e Informação Biomédica


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Id: lil-634695
Autor: Galvagno, Miguel A; Iannone, Leopoldo J; Bianchi, Jorgelina; Kronberg, Florencia; Rost, Enrique; Carstens, Maria R; Cerrutti, Patricia.
Título: Optimization of biomass production of a mutant of Yarrowia lipolytica with an increased lipase activity using raw glycerol
Fonte: Rev. argent. microbiol;43(3):218-225, jun.-set. 2011. graf, tab.
Idioma: en.
Resumo: The yeast Yarrowia lipolytica accumulates oils and is able to produce extracellular lipases when growing in different carbon sources including glycerol, the principal by-product of the biodiesel industry. In this study, biomass production of a novel mutant strain of Y. lipolytica was statistically optimized by Response Surface Methodology in media containing biodiesel-derived glycerol as main carbon source. This strain exhibited distinctive morphological and fatty acid profile characteristics, and showed an increased extracellular lipase activity. An organic source of nitrogen and the addition of 1.0 g/l olive oil were necessary for significant lipase production. Plackett-Burman and Central Composite Statistical Designs were employed for screening and optimization of fermentation in shaken flasks cultures, and the maximum values obtained were 16.1 g/l for biomass and 12.2 Units/ml for lipase, respectively. Optimized batch bioprocess was thereafter scaled in aerated bioreactors and the values reached for lipase specific activity after 95 % of the glycerol had been consumed, were three-fold higher than those obtained in shaken flasks cultures. A sustainable bioprocess to obtain biomass and extracellular lipase activity was attained by maximizing the use of the by-products of biodiesel industry.

Optimización de la producción de biomasa usando glicerol crudo, de una cepa mutante de Yarrowia lipolytica con actividad incrementada de lipasa. La levadura Yarrowia lipolytica acumula aceites y produce una lipasa extracelular al crecer en diferentes fuentes de carbono, entre ellas el glicerol, principal subproducto de la creciente industria del biodiésel. En el presente trabajo, se optimizó mediante la metodología de superficies de respuesta la producción de biomasa de una nueva cepa mutante de Y. lipolytica, empleando medios con glicerol derivado de la industria del biodiésel como principal fuente de carbono. Esta cepa presentó características morfológicas y perfil de ácidos grasos distintivos, y una mayor actividad de lipasa extracelular. Para obtener una producción significativa de lipasa extracelular, fue necesario el agregado de una fuente orgánica de nitrógeno y de 1 g/l de aceite de oliva. Se utilizaron los diseños estadísticos de Plackett-Burman y central compuesto para la selección y la optimización de las fermentaciones en frascos agitados; los máximos valores de biomasa y de lipasa obtenidos fueron de 16,1 g/l y 12,2 unidades/ml, respectivamente. Luego, el bioproceso en lote optimizado se escaló a biorreactores aireados, y los valores de actividad específica de lipasa alcanzados después de haberse consumido el 95 % del glicerol fueron tres veces más altos que los obtenidos en los cultivos en frascos agitados. En suma, se desarrolló un bioproceso sostenible para la obtención de biomasa y de una actividad de lipasa extracelular, que a la vez maximiza el uso de subproductos de la industria del biodiésel.
Descritores: Biomassa
Meios de Cultura/farmacologia
Proteínas Fúngicas/genética
Glicerol/farmacologia
Microbiologia Industrial/métodos
Lipase/genética
Micologia/métodos
Yarrowia/crescimento & desenvolvimento
-Reatores Biológicos
Biocombustíveis/análise
Meios de Cultivo Condicionados/química
DNA Fúngico/genética
DNA Intergênico/genética
Fermentação
Proteínas Fúngicas/biossíntese
Genes Fúngicos
Glicerol/isolamento & purificação
Hifas/ultraestrutura
Lipase/biossíntese
Yarrowia/enzimologia
Yarrowia/genética
Yarrowia/ultraestrutura
Responsável: AR1.2 - Instituto de Investigaciónes Epidemiológicas


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Id: lil-553764
Autor: Basso, T. S; Pungartnik, C; Brendel, M.
Título: Low productivity of ribonucleotide reductase in Saccharomyces cerevisiae increases sensitivity to stannous chloride
Fonte: Genet. mol. res. (Online);7(1):1-6, Jan. 2008. ilus.
Idioma: en.
Resumo: Ribonucleotide reductase (RNR) of the yeast Saccharomyces cerevisiae is a tetrameric protein complex, consisting of two large and two small subunits. The small subunits Y2 and Y4 form a heterodimer and are encoded by yeast genes RNR2 and RNR4, respectively. Loss of Y4 in yeast mutant rnr4delta can be compensated for by up-regulated expression of Y2, and the formation of a small subunit Y2Y2 homodimer that allows for a partially functional RNR. However, rnr4delta mutants exhibit slower growth than wild-type (WT) cells and are sensitive to many mutagens, amongst them UVC and photo-activated mono- and bi-functional psoralens. Cells of the haploid rnr4delta mutant also show a 3- to 4-fold higher sensitivity to the oxidative stress-inducing chemical stannous chloride than those of the isogenic WT. Both strains acquired increased resistance to SnCl2 with age of culture, i.e., 24-h cultures were more sensitive than cells grown for 2, 3, 4, and 5 days in liquid culture. However, the sensitivity factor of three to four (WT/mutant) did not change significantly. Cultures of the rnr4delta mutant in stationary phase of growth always showed higher frequency of budding cells (budding index around 0.5) than those of the corresponding WT (budding index <0.1), pointing to a delay of mitosis/cytokinesis.
Descritores: Compostos de Estanho/toxicidade
Genes Fúngicos/genética
Mutagênicos/toxicidade
Ribonucleotídeo Redutases/genética
Saccharomyces cerevisiae/enzimologia
-Sobrevivência Celular
Dimerização
Haploidia
Mutação
RNA Fúngico/biossíntese
Ribonucleotídeo Redutases/química
Saccharomycetales
Sensibilidade e Especificidade
Saccharomyces cerevisiae/citologia
Saccharomyces cerevisiae/genética
Fatores de Tempo
Responsável: BR26.1 - Biblioteca Central



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