Abstract

Paracoccidioides brasiliensis, the causative agent of Paracoccidioidomycosis, can grow as mycelial or yeast. Extracellular proteins secreted by fungus can be key mediators of the host-parasite interaction. Therefore, a comprehensive description of secretome of P. brasiliensis is vital to gain insights into this pathogenesis and will be valuable in identifying novel virulence factors. Secreted proteins from yeast and mycelial cells of P. brasiliensis, isolate Pb01 (ATCC MYA-826), were obtained from Fava-Netto's liquid medium for 24h in 36°C and 22°C shaking incubator, respectively. The separation of secreted proteins was realized by 2D-PAGE. Spots were with trypsin and identified by Mascot software. The identified proteins were described in functional categories according to the MIPS Functional Catalogue Database and analyzed by SignalP 3.0 software to prediction of signal peptides and SecretomeP 2.0 software to prediction of non-classical pathways. Among the eighty one and thirty seven spots were identified from hyphal and yeast secretome, respectively. The most of identified proteins are involved in RDV, including defense proteins as chaperonas and foldases that are important part of the cells machinery for protein folding and help to protect cells from stress. Others proteins important for virulence are beta-lactamase family protein, SOD and GST. In addition, were detected two isoforms of a peroxisomal catalase, which had the role in the virulence of P. brasiliensis described previously. The in silico analysis showed: putative signal peptides were detected in 16/17%; in other hand, 58/52% were predicted to be non-classically secreted, respectively for yeast and hyphal secretome. Our data are in agreement with Fungal Secretome Database (FSD). These results include proteins of interest that are important to understand the mechanisms of secretion in this fungus other than the endoplasmic reticulum-Golgi pathway. Here, we reported a suitable approach to identify secreted proteins in the culture supernatant of P. brasiliensis and provides new perspectives for the study of molecules potentially involved in the host-parasite interaction, virulence and pathogeneses. ਀䘀椀渀愀渀挀椀愀氀 匀甀瀀瀀漀爀琀㨀 䌀一倀焀Ⰰ 䘀䤀一䔀倀Ⰰ 䘀䄀倀䔀䜀