Programa de Pós-graduação em Medicina Tropical e Saúde Pública
URI Permanente desta comunidade
Navegar
Navegando Programa de Pós-graduação em Medicina Tropical e Saúde Pública por Por Orientador "Bailão, Alexandre Melo"
Agora exibindo 1 - 3 de 3
Resultados por página
Opções de Ordenação
Item Identificação por imunoproteômica dos exoantígenos do complexo paracoccidioides, com potencial aplicação no diagnóstico e terapia da paracoccidioidomicose(Universidade Federal de Goiás, 2019-08-26) Moreira, André Luís Elias; Bailão, Alexandre Melo; http://lattes.cnpq.br/5415221996976886; Bailão, Alexandre Melo; Borges, Clayton Luiz; Silva Neto, Benedito Rodrigues da; Rocha, Thiago Lopes; Oliveira, Milton Adriano Pelli deIdentification by immunoproteomic of exoantigens of the Paracoccidioides complex, with potential application in diagnosis and therapy of Paracoccidioidomycosis Fungi of Paracoccidioides complex are the etiological agents of Paracoccidioidomycosis (PCM), a systemic mycosis restricted to Latin American countries. Currently, the Paracoccidioides genus is represented by P. lutzii, P. americana, P. brasiliensis, P. restrepiensis and P. venezuelensis. In some cases, oral and skin mucosal lesions caused by other pathogens may coincide with lesions caused by Paracoccidioides spp.. Moreover, even with the advances in immunological techniques used for the diagnosis of fungal diseases, false-positive results rates for PCM are present. Thus, we investigated which antigens are secreted by 4 species of the Paracoccidioides complex in order to identify and characterize new molecules, thus increasing the spectrum of antigens to be used for future diagnostic tests of PCM. Through of nanoUPLC-MSE, 79 exoantigens were identified in 4 Paracoccidioides species. In silico analysis revealed 2 exoantigens exclusive to P. lutzii species, as well as the identification of 44 unique B-cell epitopes of the Paracoccidioides complex. Thirteen exclusive epitopes distributed among Paracoccidioides species also predicted, being this excellent molecules to be employed in the future for epidemiological studies. These results demonstrate a range of epitopes exclusive to the Paracoccidioides complex as well as the identification of molecules unique to each fungal species. In addition, these analyzes allowed the identification of new candidate biomarkers to PCM diagnosis, as well as the identification of molecules to be used as future epidemiological biomarkers.Item Metabolismo do propionato em Paracoccidioides lutzii(Universidade Federal de Goiás, 2015-01-30) Santos, Luiz Paulo Araújo dos; Bailão, Alexandre Melo; http://lattes.cnpq.br/5415221996976886; Bailão, Alexandre Melo; Borges, Clayton Luiz; Bailão, Elisa Flávia Luiz CardosoPathogens can find different carbon sources in host niches generating propionyl-CoA, among them propionate. This compound is toxic to the organism if accumulated within the cell, and can be generated in the host tissue by the metabolism of amino acids isoleucine, valine and methionine, or by the metabolism of odd-chain fatty acids. Therefore, during infection, the propionyl-CoA metabolism to nontoxic nutrient and usable energetically is of great relevance. Nonetheless, there are no studies about the propionyl-CoA metabolization pathway in fungi of the genus Paracoccidioides, causer of paracoccidioidomycosis, a systemic mycosis of high incidence in Latin America. Thus, to characterize of which metabolic pathway this fungus utilizes to propionyl-CoA metabolization, it was made a search the genes coding to enzymes of methylcitrate cycle in genome of Paracoccidioides spp. and were identified genes coding to the three exclusive enzymes of this cycle, which are methylcitrate synthase, methylcitrate dehydrogenase and methylcitrate lyase. After analysis of growth and viability, which demonstrated that Paracoccidioides lutzii utilizes propionate as carbon source, it was made gene expression analysis of enzymes of methylcitrate cycle and was observed that are regulated in response to propionate. Additionally, the enzymatic activity of the MCS showed that this enzyme is active inside of fungal cells and also when is secreted, as well as its dual capacity of to act with a citrate synthase and metylcitrate synthase. Finally, the proteomic profile of P. lutzii in propionate showed enzymes induction of methylcitrate cycle, glyoxylate cycle, amino acid metabolism and gluconeogenesis, and the repression of glycolytic pathway, fermentation and fatty acid synthesis, which demonstrated of metabolic rearrangement to supply the cellular energetic demand, metabolizing propionate. In this sense, to understand the mechanism of propionyl-CoA metabolism in P. lutzii provides data for visualization of metabolic adaptation that this fungus makes use in different colonization of niches.Item Estudo a homeostase de cobre no fungo patogênico histoplasma capsulatum(Universidade Federal de Goiás, 2018-07-18) Tristão, Gabriel Brum; Bailão, Alexandre Melo; http://lattes.cnpq.br/5415221996976886; Bailão, Alexandre Melo; Malavazi, Iran; Lima, Patrícia de Sousa; Bailão, Elisa Flávia Luiz Cardoso; Paccez, Juliano DomiraciHistoplasma capsulatum is a thermodymorphic pathogenic fungus that causes systemic mycosis known as histoplasmosis. This fungus grows as mycelium at temperatures around 25°C and as yeast at 37°C. During the infectious process, pathogenic microorganisms must obtain nutrients from the host in order to survive in infected tissues. Among these nutrients, copper is an essential metal ion, because it participates in oxidation/reduction reactions, in energy production, in the transport of electrons, its cofactor of many enzymes and metalloproteins and is required for energy and melanin production. Copper excess however, it is toxic due to the fact that produces reactive oxygen species, dislocates other metals from metalloproteins, causes damage to lipids and DNA, so because of this H. capsulatum must maintain the homeostasis of this metal during infection. We observed here that H. capsulatum, through the transcriptional levels of Ctr4, Mac1, Crp1 and Ace1, during the infectious process in macrophages, faces an environment of copper overload imposed by the host cells via copper ATPase ATP7a. This copper excess shown to be INF-ɣ and time dependent, because when macrophages are not stimulated by INF-ɣ and in greater times of infection, they impose a restrictive copper environment instead, during the infection. H. capsulatum uses the Crp1 copper efflux pump in order to respond this toxic copper milieu, since mutant yeasts for Crp1 were unable to grow at high levels of the metal. Despite the importance of Crp1 for the fungus in this context, it appears that Crp1 is not strictly necessary for the total virulence of the fungus, leading us to infer that other proteins may also be exerting a Crp1-like function in H. capsulatum. It is clear once again that in the pathogen-host relationship copper plays a complex, highly dynamic and dependent on certain biological variables role.