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Paracoccidioidomycosis (PCM) is a life-threatening systemic mycosis widely reported in the Gran Chaco ecosystem. The disease is caused by different species from the genus Paracoccidioides, which are all endemic to South and Central America. Here, we sequenced and analyzed 31 isolates of Paracoccidioides across South America, with particular focus on isolates from Argentina and Paraguay. The de novo sequenced isolates were compared with publicly available genomes. Phylogenetics and population genomics revealed that PCM in Argentina and Paraguay is caused by three distinct Paracoccidioides genotypes, P. brasiliensis (S1a and S1b) and P. restrepiensis (PS3). P. brasiliensis S1a isolates from Argentina are frequently associated with chronic forms of the disease. Our results suggest the existence of extensive molecular polymorphism among Paracoccidioides species, and provide a framework to begin to dissect the connection between genotypic differences in the pathogen and the clinical outcomes of the disease., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest., (Copyright © 2020. Published by Elsevier Inc.)

The genus Paracoccidioides comprises a complex of phylogenetic species of dimorphic pathogenic fungi, the etiologic agents of paracoccidioidomycosis (PCM), a disease confined to Latin America and of marked relevance in its endemic areas due to its high frequency and severity. The members of the Paracoccidioides genus are distributed in distinct phylogenetic species (S1, PS2, PS3 and 01-like) that potentially differ in their biochemical and molecular characteristics. In this work, we performed the proteomic characterization of different members of the genus Paracoccidioides. We compared the proteomic profiles of Pb01 (01-like), Pb2 (PS2), Pb339 (S1) and PbEPM83 (PS3) using 2D electrophoresis and mass spectrometry. The proteins/isoforms were selected based on the staining intensity of the spots as determined by image analysis. The proteins/isoforms were in-gel digested and identified by peptide mass fingerprinting and ion fragmentation. A total of 714 spots were detected, of which 343 were analyzed. From these spots, 301 represented differentially expressed proteins/isoforms among the four analyzed isolates, as determined by ANOVA. After applying the FDR correction, a total of 267 spots were determined to be differentially expressed. From the total, 193 proteins/isoforms were identified by PMF and confirmed by ion fragmentation. Comparing the expression profiles of the isolates, the proteins/isoforms that were related to glycolysis/gluconeogenesis and to alcohol fermentation were more abundant in Pb01 than in other representatives of the genus Paracoccidioides, indicating ahigher use of anaerobic pathways for energy production. Those enzymes related to the oxidative stress response were more abundant in Pb01, Pb2 and Pb339, indicating a better response to ROS in these members of the Paracoccidioides complex. The enzymes of the pentose phosphate pathway were abundant in Pb2. Antigenic proteins, such as GP43 and a 27-kDa antigenic protein, were less abundant in Pb01 and Pb2. The proteomic profile indicates metabolic differences among the analyzed members of the Paracoccidioides genus., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Paracoccidioides brasiliensis is a thermodimorphic fungus associated with paracoccidioidomycosis (PCM), the most common systemic mycosis in Latin America. The infection is initiated by inhalation of environmentally dispersed conidia produced by the saprophytic phase of the fungus. In the lungs, P. brasiliensis assumes the parasitic yeast form and must cope with the adverse conditions imposed by cells of the host immune system, which includes a harsh environment, highly concentrated in reactive oxygen species (ROS). In this work, we used the ROS-generating agent paraquat to experimentally simulate oxidative stress conditions in order to evaluate the stress-induced modulation of gene expression in cultured P. brasiliensis yeast cells, using a microarray hybridization approach. The large-scale evaluation inherent to microarray-based analyses identified 2070 genes differentially transcribed in response to paraquat exposure, allowing an integrated visualization of the major metabolic changes that constitute the systemic defense mechanism used by the fungus to overcome the deleterious effects of ROS. These include overexpression of detoxifying agents, as well as of molecular scavengers and genes involved in maintenance of the intracellular redox potential. Particularly noteworthy was to verify that the oxidative stress resistance mechanism of P. brasiliensis also involves coordinated overexpression of a series of genes responsible for chitin-biosynthesis, suggesting that this pathway may constitute a specific regulon. Further analyses aiming at confirming and understanding the mechanisms that control such regulon may provide interesting new targets for chemotherapeutic approaches against P. brasiliensis and other pathogenic fungi., (Copyright © 2013 Elsevier Inc. All rights reserved.)