XI International Meeting on Paracoccidioidomycosis

XI International Meeting on Paracoccidioidomycosis

Resume:32-1

Oral / Poster

32-1	Secretome of Aspergillus fumigatus
Authors:	Gabriela Westerlund Peixoto Neves (UERJ - Universidade do Estado do Rio de Janeiro) ; Paula Kubitschek-barreira (UERJ - Universidade do Estado do Rio de Janeiro) ; Shelly Hagag (TAU - Tel-Aviv University) ; Nir Osherov (TAU - Tel-Aviv University) ; Leila Maria Lopes Bezerra (UERJ - Universidade do Estado do Rio de Janeiro)

Abstract

Aspergillus fumigatus is the most prevalent airborne opportunistic fungal pathogen, causing severe and usually fatal invasive infections. This species is the most common etiologic agent of invasive aspergillosis among aspergilli. Invasive aspergillosis is the main life-threatening infections in Hematologic Units, affecting especially patients with long-term neutropeny. The infection begins by the inhalation of air-borne conidia which reach the alveoli and germinate producing angioinvasive hyphae. These hyphae adhere to and penetrate the endothelium, leading to a pro-thrombosis and tissue infarction clinical frame. During this process many virulence factors can be involved such as secreted toxins and extracellular enzymes. The aim of this study was to analyze the secretome of a wild-type and a mutant strain of Aspergillus fumigatus. This mutant lacks a transcription factor (prtT) responsible for the expression of many proteases in this fungus. In this work was used two proteomic approaches: 1D-MS/MS and 2DE-MS/MS. A combination of these methodologies was applied to identify the proteins present in the secretome of Apergillus fumigatus. Among the proteins identified we can highlight an alkaline serine protease (ALP); a GPI-anchored beta 1,3 endoglucanase; a dipeptidyl peptidase; FAD oxygenase, chitosanase and a 18 KDa antigen, a ribotoxin described as an allergen of A. fumigatus. A comparative proteomic analysis of the secretome using the mutant strain (ΔprtT) was performed by a 2D-DIGE approach. Other proteins were identified in the secretome of this mutant as a 1,3-(beta) glucanosiltransferase, a carboxipeptidase and an arabinanase. Some of the proteins identified are being described for the first time in the secretome of this pathogen. Financial support: CNPq, Ministério da Saúde e Faperj.

Keyword: Aspergillus fumigatus, Secretome, Enzymes

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