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Pesquisa : G05.308.330 [Categoria DeCS]
Referências encontradas : 27 [refinar]
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  1 / 27 LILACS  
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Id: biblio-974323
Autor: Wang, Xiuwen; Zhang, Xiaohua; Yao, Qingshou; Hua, Dongliang; Qin, Jiayang.
Título: Comparative proteomic analyses of Hyphozyma roseonigra ATCC 20624 in response to sclareol
Fonte: Braz. j. microbiol;49(supl.1):160-165, 2018. tab, graf.
Idioma: en.
Projeto: National Natural Science Foundation of China; . Shandong Province Science and Technology Project; . Jinan Youth Science and Technology Star Project.
Resumo: Abstract Sclareol is an important intermediate for ambroxide synthesis industries. Hyphozyma roseonigra ATCC 20624 was the only reported strain capable of degrading sclareol to the main product of sclareol glycol, which is the precursor of ambroxide. To date, knowledge is lacking about the effects of sclareol on cells and the proteins involved in sclareol metabolism. Comparative proteomic analyses were conducted on the strain H. roseonigra ATCC 20624 by using sclareol or glucose as the sole carbon source. A total of 79 up-regulated protein spots with a >2.0-fold difference in abundance on 2-D gels under sclareol stress conditions were collected for further identification. Seventy spots were successfully identified and finally integrated into 30 proteins. The up-regulated proteins under sclareol stress are involved in carbon metabolism; and nitrogen metabolism; and replication, transcription, and translation processes. Eighteen up-regulated spots were identified as aldehyde dehydrogenases, which indicating that aldehyde dehydrogenases might play an important role in sclareol metabolism. Overall, this study may lay the fundamentals for further cell engineering to improve sclareol glycol production.
Descritores: Ascomicetos/metabolismo
Proteínas Fúngicas/metabolismo
Diterpenos/metabolismo
-Ascomicetos/genética
Ascomicetos/química
Proteínas Fúngicas/química
Carbono/metabolismo
Eletroforese em Gel Bidimensional
Regulação Fúngica da Expressão Gênica
Proteômica
Glucose/metabolismo
Responsável: BR1.1 - BIREME


  2 / 27 LILACS  
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Id: lil-780832
Autor: Yao, Lin; Tan, Chong; Song, Jinzhu; Yang, Qian; Yu, Lijie; Li, Xinling.
Título: Isolation and expression of two polyketide synthase genes from Trichoderma harzianum 88 during mycoparasitism
Fonte: Braz. j. microbiol;47(2):468-479, Apr.-June 2016. tab, graf.
Idioma: en.
Projeto: National Science Foundation for Distinguished Young Scholars of China.
Resumo: Abstract Metabolites of mycoparasitic fungal species such as Trichoderma harzianum 88 have important biological roles. In this study, two new ketoacyl synthase (KS) fragments were isolated from cultured Trichoderma harzianum 88 mycelia using degenerate primers and analysed using a phylogenetic tree. The gene fragments were determined to be present as single copies in Trichoderma harzianum 88 through southern blot analysis using digoxigenin-labelled KS gene fragments as probes. The complete sequence analysis in formation of pksT-1 (5669 bp) and pksT-2 (7901 bp) suggests that pksT-1 exhibited features of a non-reducing type I fungal PKS, whereas pksT-2 exhibited features of a highly reducing type I fungal PKS. Reverse transcription polymerase chain reaction indicated that the isolated genes are differentially regulated in Trichoderma harzianum 88 during challenge with three fungal plant pathogens, which suggests that they participate in the response of Trichoderma harzianum 88 to fungal plant pathogens. Furthermore, disruption of the pksT-2 encoding ketosynthase–acyltransferase domains through Agrobacterium -mediated gene transformation indicated that pksT-2 is a key factor for conidial pigmentation in Trichoderma harzianum 88.
Descritores: Trichoderma/enzimologia
Proteínas Fúngicas/metabolismo
Policetídeo Sintases/metabolismo
-Doenças das Plantas/microbiologia
Trichoderma/classificação
Trichoderma/genética
Proteínas Fúngicas/genética
Proteínas Fúngicas/química
Dados de Sequência Molecular
Regulação Fúngica da Expressão Gênica
Alinhamento de Sequência
Sequência de Aminoácidos
Micélio/enzimologia
Micélio/genética
Policetídeo Sintases/genética
Policetídeo Sintases/química
Responsável: BR1.1 - BIREME


  3 / 27 LILACS  
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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
Seres Humanos
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: CL1.1 - Biblioteca Central


  4 / 27 LILACS  
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Id: lil-727016
Autor: Pérez, Edmundo A.; Fernández, Francisco J.; Fierro, Francisco; Mejía, Armando; Marcos, Ana T.; Martín, Juan F.; Barrios-González, Javier.
Título: Yeast HXK2 gene reverts glucose regulation mutation of penicillin biosynthesis in P. chrysogenum
Fonte: Braz. j. microbiol;45(3):873-883, July-Sept. 2014. ilus, graf, tab.
Idioma: en.
Resumo: The mutant Penicillium chrysogenum strain dogR5, derived from strain AS-P-78, does not respond to glucose regulation of penicillin biosynthesis and β-galactosidase, and is partially deficient in D-glucose phosphorilating activity. We have transformed strain dogR5 with the (hexokinase) hxk2 gene from Saccharomyces cerevisiae. Transformants recovered glucose control of penicillin biosynthesis in different degrees, and acquired a hexokinase (fructose phosphorylating) activity absent in strains AS- P-78 and dogR5. Interestingly, they also recovered glucose regulation of β-galactosidase. On the other hand, glucokinase activity was affected in different ways in the transformants; one of which showed a lower activity than the parental dogR5, but normal glucose regulation of penicillin biosynthesis. Our results show that Penicillium chrysogenum AS-P-78 and dogR5 strains lack hexokinase, and suggest that an enzyme with glucokinase activity is involved in glucose regulation of penicillin biosynthesis and β-galactosidase, thus signaling glucose in both primary and secondary metabolism; however, catalytic and signaling activities seem to be independent.
Descritores: Regulação Fúngica da Expressão Gênica/efeitos dos fármacos
Glucose/metabolismo
Hexoquinase/metabolismo
Penicilinas/biossíntese
Penicillium chrysogenum/genética
Penicillium chrysogenum/metabolismo
Proteínas de Saccharomyces cerevisiae/metabolismo
-Hexoquinase/genética
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Proteínas de Saccharomyces cerevisiae/genética
Transformação Genética
beta-Galactosidase/biossíntese
Responsável: BR1.1 - BIREME


  5 / 27 LILACS  
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Id: lil-626734
Autor: Barham, Feiruz; Roman, Patricia; Bull, Paulina.
Título: The PcACE1 transcription factor from Phanerochaete chrysosporium contains a Cys- and Ser-rich transactivation domain
Fonte: Biol. Res;44(4):351-355, 2011. ilus, tab.
Idioma: en.
Projeto: FONDECYT; . VRI.
Resumo: Transcription factor Ace1 from Saccharomyces cerevisiae regulates the expression of target genes when the copper concentration reaches 200 ìÌ levels. We are studying the ortholog of Ace1 from fungus Phanerochaete chrysosporium PcACE1, isolated by complementation in yeast. In this report we show the localization of the transactivation region of PcACE1. Different PcACE1 fragments were ligated in frame to the GAL4 DNA-binding domain by site-directed mutagenesis in a suitable yeast expression vector. Transformation of an appropriate Saccharomyces cerevisiae strain was used as host. This strain contains the fusion GAL1:lacZ in its genome under the control of promoter sequences recognized by GAL4. Finally, we measured â-galactosidase activity in each yeast clone. The activation of the reporter gene is proportional to the transactivation capacity of the transcription factor PcACE1. The results obtained indicate that PcACE1 transactivation domain is located in the carboxy terminal half and contains an array of cysteines in the form of Cys-X-Cys and Cys-X2-Cys and a 60% of Ser. Therefore, these results show that this type of Cys motif can function as transcription activating domain not only in transcription factors that respond to minimal copper concentrations but also in those that respond to high copper concentrations. This is the first transactivation domain reported in a basidiomycete fungus.
Descritores: Regulação Fúngica da Expressão Gênica/genética
Phanerochaete/genética
Fatores de Transcrição/genética
Transcrição Genética/genética
Ativação Transcricional/genética
-Sequência de Bases
Dados de Sequência Molecular
Reação em Cadeia da Polimerase Via Transcriptase Reversa
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: CL1.1 - Biblioteca Central


  6 / 27 LILACS  
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Id: lil-568995
Autor: Loureiro y Penha, C. V; Kubitschek, P. H. B; Larcher, G; Perales, J; Rodriguez León, I; Lopes-Bezerra, L. M; Bouchara, J. P.
Título: Proteomic analysis of cytosolic proteins associated with petite mutations in Candida glabrata
Fonte: Braz. j. med. biol. res = Rev. bras. pesqui. méd. biol;43(12):1203-1214, Dec. 2010. ilus, tab.
Idioma: en.
Resumo: The incidence of superficial or deep-seated infections due to Candida glabrata has increased markedly, probably because of the low intrinsic susceptibility of this microorganism to azole antifungals and its relatively high propensity to acquire azole resistance. To determine changes in the C. glabrata proteome associated with petite mutations, cytosolic extracts from an azole-resistant petite mutant of C. glabrata induced by exposure to ethidium bromide, and from its azole-susceptible parent isolate were compared by two-dimensional polyacrylamide gel electrophoresis. Proteins of interest were identified by peptide mass fingerprinting or sequence tagging using a matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometer. Tryptic peptides from a total of 160 Coomassie-positive spots were analyzed for each strain. Sixty-five different proteins were identified in the cytosolic extracts of the parent strain and 58 in the petite mutant. Among the proteins identified, 10 were higher in the mutant strain, whereas 23 were lower compared to the parent strain. The results revealed a significant decrease in the enzymes associated with the metabolic rate of mutant cells such as aconitase, transaldolase, and pyruvate kinase, and changes in the levels of specific heat shock proteins. Moreover, transketolase, aconitase and catalase activity measurements decreased significantly in the ethidium bromide-induced petite mutant. These data may be useful for designing experiments to obtain a better understanding of the nuclear response to impairment of mitochondrial function associated with this mutation in C. glabrata.
Descritores: Candida glabrata/química
Proteínas Fúngicas/análise
Mutação/genética
Proteoma/análise
-Antifúngicos/farmacologia
Azóis/farmacologia
Candida glabrata/efeitos dos fármacos
Candida glabrata/genética
Farmacorresistência Fúngica/genética
Eletroforese em Gel Bidimensional
Proteínas Fúngicas/genética
Regulação Fúngica da Expressão Gênica
Proteoma/genética
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


  7 / 27 LILACS  
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Id: lil-567534
Autor: Andrade, Cherie; Sepulveda, Carolina; Cardemil, Emilio; Jabalquinto, Ana M.
Título: The Role of Tyrosine 207 in the Reaction Catalyzed by Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase
Fonte: Biol. Res;43(2):191-195, 2010. ilus.
Idioma: en.
Projeto: funding from NSF; . NIH; . FONDECYT; . USACH. DICYT.
Resumo: The functional signifcance of tyrosine 207 of Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase was explored by examining the kinetic properties of the Tyr207Leu mutant. The variant enzyme retained the structural characteristics of the wild-type protein as indicated by circular dichroism, intrinsic fuorescence spectroscopy, and gel-exclusion chromatography. Kinetic analyses of the mutated variant showed a 15-fold increase in Km CO2, a 32fold decrease in Vmax, and a 6-fold decrease in Km for phosphoenolpyruvate. These results suggest that the hydroxyl group of Tyr 207 may polarize CO2 and oxaloacetate, thus facilitating the carboxylation/decarboxylation steps.
Descritores: Mutação/genética
Fosfoenolpiruvato Carboxilase/genética
Saccharomyces cerevisiae/enzimologia
Tirosina/genética
-Catálise
Cromatografia em Gel
Dicroísmo Circular
Regulação Enzimológica da Expressão Gênica
Regulação Fúngica da Expressão Gênica
Fosfoenolpiruvato Carboxilase/química
Espectrometria de Fluorescência
Tirosina/química
Tipo de Publ: Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Responsável: CL1.1 - Biblioteca Central


  8 / 27 LILACS  
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Soares, Célia Maria de Almeida
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Id: lil-517022
Autor: Pereira, Maristela; Bailão, Alexandre Melo; Parente, Juliana Alves; Borges, Clayton Luiz; Salem-Izacc, Silvia Maria; Soares, Célia Maria de Almeida.
Título: Preferential transcription of Paracoccidioides brasiliensis genes: host niche and time-dependent expression
Fonte: Mem. Inst. Oswaldo Cruz;104(3):486-491, May 2009. ilus.
Idioma: en.
Projeto: CNPq.
Resumo: Paracoccidioides brasiliensis causes infection through inhalation by the host of airborne propagules from the mycelium phase of the fungus. This fungus reaches the lungs, differentiates into the yeast form and is then disseminated to virtually all parts of the body. Here we review the identification of differentially-expressed genes in host-interaction conditions. These genes were identified by analyzing expressed sequence tags (ESTs) from P. brasiliensis cDNA libraries. The P. brasiliensis was recovered from infected mouse liver as well as from fungal yeast cells incubated in human blood and plasma, mimicking fungal dissemination to organs and tissues and sites of infection with inflammation, respectively. In addition, ESTs from a cDNA library of P. brasiliensis mycelium undergoing the transition to yeast were previously analyzed. Together, these studies reveal significant changes in the expression of a number of genes of potential importance in the host-fungus interaction. In addition, the unique and divergent representation of transcripts when the cDNA libraries are compared suggests differential gene expression in response to specific niches in the host. This analysis of gene expression patterns provides details about host-pathogen interactions and peculiarities of sites within the host.
Descritores: Etiquetas de Sequências Expressas
Perfilação da Expressão Gênica
Regulação Fúngica da Expressão Gênica/genética
Interações Hospedeiro-Patógeno/genética
Paracoccidioides/genética
-DNA Complementar/análise
Biblioteca Gênica
Fígado/microbiologia
Paracoccidioides/patogenicidade
Limites: Animais
Seres Humanos
Camundongos
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


  9 / 27 LILACS  
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Id: lil-490636
Autor: Niklitschek, Mauricio; Alcaíno, Jennifer; Barahona, Salvador; Sepúlveda, Dionisia; Lozano, Carla; Carmona, Marisela; Marcoleta, Andrés; Martínez, Claudio; Lodato, Patricia; Baeza, Marcelo; Cifuentes, Víctor.
Título: Genomic organization of the structural genes controlling the astaxanthin biosynthesis pathway of Xanthophyllomyces dendrorhous
Fonte: Biol. Res;41(1):93-108, 2008. ilus, tab.
Idioma: en.
Projeto: Fondecyt; . Mecesup.
Resumo: The cloning and nucleotide sequence of the genes (idi, crtE, crtYB, crtl and crtS) controlling the astaxanthin biosynthesis pathway of the wild-type ATCC 24230 strain of Xanthophyllomyces dendrorhous in their genomic and cDNA version were obtained. The idi, crtE, crtYB, crtl and crtS genes were cloned, as fragments of 10.9, 11.5, 15.8, 5.9 and 4 kb respectively. The nucleotide sequence data analysis indicates that the idi, crtE, crtYB, crtl and crtS genes have 4, 8,4, 11, and 17 introns and 5, 9, 5, 12 and 18 exons respectively. In addition, a highly efficient site-directed mutagenesis system was developed by transformation by integration, followed by mitotic recombination (the double recombinant method). Heterozygote idi (idi+ / idi-::hph), crtE (crtE+ / crtE -::hph), crtYB (crtYB + / crtYB -::hph), crtI (crtI+ / crtI-::hph) and crtS (crtS +/crtS -::hph) and homozygote mutants crtYB (crtYB -::hph/crtYB -::hph), crtI (crtI -::hph/crtI -::hph) and crtS (crtS -::hph / crtS -::hph) were constructed. All the heterozygote mutants have a pale phenotype and produce less carotenoids than the wild-type strain. The genetic analysis of the crtYB, crtl and crtS loci in the wild-type, heterozygote, and homozygote give evidence of the diploid constitution of ATCC 24230 strains. In addition, the cloning of a truncated form of the crtYB that lacks 153 amino acids of the N-terminal region derived from alternatively spliced mRNA was obtained. Their heterologous expression in Escherichia coli carrying the carotenogenic cluster of Erwinia uredovora result in trans-complementation and give evidence of its functionality in this bacterium, maintaining its phytoene synthase activity but not the lycopene cyclase activity.
Descritores: Basidiomycota/genética
Regulação Fúngica da Expressão Gênica/genética
-Sequência de Aminoácidos
Sequência de Bases
Clonagem Molecular
DNA Complementar/genética
Genes Fúngicos/genética
Reação em Cadeia da Polimerase
RNA Fúngico/genética
Xantofilas/biossíntese
Xantofilas/genética
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


  10 / 27 LILACS  
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Id: lil-482029
Autor: Ferreira, R. C; Bosco, F; Paiva, P. B; Briones, M. R.
Título: Minimization of transcriptional temporal noise and scale invariance in the yeast genome
Fonte: Genet. mol. res. (Online);6(2):397-414, 2007. graf, tab.
Idioma: en.
Resumo: The analysis of transcriptional temporal noise could be an interesting means to study gene expression dynamics and stochasticity in eukaryotes. To study the statistical distributions of temporal noise in the eukaryotic model system Saccharomyces cerevisiae, we analyzed microarray data corresponding to one cell cycle for 6200 genes. We found that the temporal noise follows a lognormal distribution with scale invariance at the genome, chromosomal and sub-chromosomal levels. Correlation of temporal noise with the codon adaptation index suggests that at least 70% of all protein-coding genes are a noise minimization core of the genome. Accordingly, a mathematical model of individual gene expression dynamics was proposed, using an operator theoretical approach, which reveals strict conditions for noise variability and a possible global noise minimization/optimization strategy at the genome level. Our model and data show that minimal noise does not correspond to genes obeying a strictly deterministic dynamics. The natural strategy of minimization consists in equating the mean of the absolute value of the relative variation of the expression level (alpha) with noise (eta). We hypothesize that the temporal noise pattern is an emergent property of the genome and shows how the dynamics of gene expression could be related to chromosomal organization.
Descritores: Genoma Fúngico
Saccharomyces cerevisiae/genética
Transcrição Genética
-Regulação Fúngica da Expressão Gênica
Redes Reguladoras de Genes
Modelos Genéticos
Modelos Estatísticos
Modelos Teóricos
Análise de Sequência com Séries de Oligonucleotídeos
Saccharomyces cerevisiae/metabolismo
Fatores de Tempo
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME



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