RESUMEN
Abstract The virulence genes in invasive aspergillosis (IA) have not been analyzed adequately. The present study was designed to evaluate the expression of gpaB and sidA genes, which are important virulence genes in Aspergillus spp. from bronchoalveolar lavage (BAL) samples. Direct examination and culture on Czapek Agar and Sabouraud Dextrose Agar media were performed for 600 BAL specimens isolated from patients with possible aspergillosis. A Galactomannan ELISA assay was also carried out. The expression levels of the gpaB and sidA genes in isolates were analyzed using quantitative real-time PCR (qRT-PCR). We identified 2 species, including Aspergillus flavus (A. flavus) and Aspergillus fumigatus (A. fumigatus) in 25 positive samples for invasive aspergillosis as validated using GM-ELISA. A. flavus is the main pathogen threatening transplant recipients and cancer patients worldwide. In this study, A. flavus had low levels of the gpaB gene expression compared to A. fumigatus (p = 0.006). The highest sidA expression was detected in transplant recipients (p = 0.05). There was no significant correlation between sidA expression and underlying disease (p = 0.15). The sidA and gpaB gene expression patterns may provide evidence that these virulence genes play important roles in the pathogenicity of Aspergillus isolates; however, there are several regulatory genes responsible for the unexpressed sidA and gpaB genes in the isolates.
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Aspergilosis/microbiología , Aspergillus flavus/metabolismo , Aspergillus flavus/patogenicidad , Aspergillus fumigatus/metabolismo , Aspergillus fumigatus/patogenicidad , Proteínas Bacterianas/metabolismo , Aspergillus flavus/aislamiento & purificación , Aspergillus flavus/genética , Aspergillus fumigatus/aislamiento & purificación , Aspergillus fumigatus/genética , Proteínas Bacterianas/genética , VirulenciaRESUMEN
Nineteen fungi and seven yeast strains were isolated from sugarcane bagasse piles from an alcohol plant located at Brazilian Cerrado and identified up to species level on the basis of the gene sequencing of 5.8S-ITS and 26S ribosomal DNA regions. Four species were identified:
Asunto(s)
Aspergillus fumigatus/enzimología , Aspergillus niger/enzimología , Celulosa/metabolismo , /metabolismo , Kluyveromyces/enzimología , Saccharum/microbiología , Xilosidasas/metabolismo , beta-Glucosidasa/metabolismo , Aspergillus fumigatus/aislamiento & purificación , Aspergillus fumigatus/metabolismo , Aspergillus niger/aislamiento & purificación , Aspergillus niger/metabolismo , Secuencia de Bases , Biomasa , Brasil , ADN de Hongos/genética , ADN Intergénico/genética , Fermentación , Kluyveromyces/aislamiento & purificación , Kluyveromyces/metabolismo , Lignina/metabolismo , Tipificación Molecular , Técnicas de Tipificación Micológica , ARN Ribosómico/genética , Análisis de Secuencia de ADNRESUMEN
Optimization of media for the maximum production of xylanase by Aspergillus fumigatus MKUI was carried out using De Meo's fractional factorial design with seven components such as NaNO3, K2HPO4, MgSO4, FeSO4. KCl, peptone and yeast extract. A. fumigatus produced a maximum of 700 U/gds of enzyme after 48 hr of incubation (before optimization). After two steps of optimization, the medium designed favoured a 2.8 fold (1950 U/gds) increase in xylanase production by A. fumigatus. Optimized medium for Aspergillus fumigatus contained (g/l) NaNO3, 15; K2HPO4, 15; MgSO4, 5; FeSO4, 0.009; KCI, 0.5; peptone, 20; and yeast extract, 10.
Asunto(s)
Aspergillus fumigatus/metabolismo , Biotecnología/métodos , Medios de Cultivo/farmacología , Fibras de la Dieta/metabolismo , Endo-1,4-beta Xilanasas/biosíntesis , Fermentación , Concentración de Iones de Hidrógeno , Modelos Estadísticos , Peptonas/farmacología , Factores de Tiempo , Xilanos/químicaRESUMEN
Três linhagens de fungos, identificadas como Aspergillus flavus, Aspergillus fumigatus e Aspergillus niger, isoladas de amostras da planta de extraçäo de ouro da Mineraçäo Morro Velho (Nova Lima, Brasil), foram testadas quanto à capacidade de remover metais pesados em uma soluçäo obtida do circuito de beneficiamento de minério de ouro da mineraçäo (liquor de lixiviaçäo). Foi investida a habilidade desses fungos em remover ouro, prata e cobre via processos independentes do metabolismo (biomassa seca) e células cultivadas no liquor de lixiviaçäo. A biomassa seca das três linhagens estudadas apresentou uma baixa capacidade de bissorçäo de metais, provavelmente devido a elevada concentraçäo de cianeto no liquor de lixiviaçäo. Os fungos A. fumigatus e A. niger, quando metabolicamente ativos, apresentaram uma elevada habilidade de remoçäo desses metais. A presença de atividade metabólica nas células fúngicas