Resumo

The paracoccidioidomycosis (PCM) is a systemic disease caused by the thermo dimorphic fungus Paracoccidioides spp. The disease is endemic in Latin America, mainly in Argentina, Colombia, Venezuela and, particularly in Brazil, where the prevalence of cases is more frequent. The main route of infection of the PCM occurs by inhalation of mycelia fragments and conidia. Until now, no proteomic studies were performed with conidia of Paracoccidioides spp. Thus, we intend to characterize the proteome of conidia of Paracoccidioides. The mycelia of Paracoccidioides, isolate 01 (ATCC MYA-826) were cultured in Petri dishes containing Potato Agar Medium for 90 days at 18 ^ºC. The production of conidia was monitored and the conidia were collected and purified. For conidia protein extraction, the cells were placed into microtubes containing glass beads and Tris-calcium buffer without protease inhibitors. The conidia were submitted to vigorous stirring for 6 cycles of 30 seconds followed by centrifugation at 4 ^ºC. The protein content of the supernatant was determined by the Bradford method. Initially, a total of 260 micrograms of proteins obtained from conidia of Paracoccidioides were subjected to tryptic digestion in ammonium bicarbonate buffer. The digested peptides were submitted, in triplicate, to the high performance liquid chromatography coupled with mass spectrometry. It were identified a total of 213 proteins present in conidia of Paracoccidioides. The proteins was classified into categories based on FUNCAT, where was possible to verify that 16% of the proteins were related to the metabolism, 23% to protein synthesis, 18% related to energy production and 10% to cell rescue, defense and virulence, among others. The identified proteins are related to some important function in pathogenic fungus. Some identified proteins were related to evasion, defense and virulence of the fungus such as: Catalase, HSP90, Mitochondrial peroxiredoxin PRX1, Aldehyde dehydrogenase and others. We also identify proteins related to the mechanism of adherence of the fungus to the host, such as: GAPDH, Enolase, Triosephosphate isomerase, all of these linked to processes related to the extracellular matrix components. All together our data suggests that conidia of Paracoccidioides contain proteins which can contribute to its maintenance in the environment and also other molecules related to important processes necessary for the initial steps of infection in the host.