Metabolic Peculiarities of Paracoccidioides brasiliensis Dimorphism as Demonstrated by iTRAQ Labeling Proteomics

Abstract

Paracoccidioidomycosis (PCM), a systemic mycosis with a high incidence in Latin America, is caused by thermodimorphic fungi of the Paracoccidioides genus. The contact with host occurs by the inhalation of conidia or mycelial propagules which once reaching the pulmonary alveoli differentiate into yeast cells. This transition process is vital in the pathogenesis of PCM allowing the fungus survival in the host. Thus, the present work performed a comparative proteome analysis of mycelia, mycelia-to-yeast transition, and yeast cells of Paracoccidioides brasiliensis . For that, tryptic peptides were labeled with iTRAQ and identified by LC–MS/MS and computational data analysis, which allowed the identification of 312 proteins differentially expressed in different morphological stages. Data showed that P. brasiliensis yeast cells preferentially employ aerobic beta-oxidation and the tricarboxylic acid cycle accompanied by oxidative phosphorylation for ATP production, in comparison to mycelia and the transition from mycelia-to-yeast cells. Furthermore, yeast cells show a metabolic reprogramming in amino acid metabolism and in the induction of virulence determinants and heat shock proteins allowing adaptation to environmental conditions during the increase of the temperature. In opposite of that, the alcoholic fermentation found to P. lutzii , at least under laboratory conditions, is strongly favored in mycelium compared to yeast cells. Thereby, the data strongly support substantial metabolic differences among members of the Paracoccidioides complex, when comparing the saprobiotic mycelia and the yeast parasitic phases.

Immunoproteomic Analysis Reveals Novel Candidate Antigens for the Diagnosis of Paracoccidioidomycosis Due to Paracoccidioides lutzii

“…The 16 specific immunogenic proteins of P. lutzii can be divided into three main groups. Group 1 comprises seven proteins that have been widely reported in Paracoccidioides under experimental physiological conditions according to STRING analysis, namely, triosephosphate isomerase, glyceraldehyde-3-phosphate dehydrogenase, citrate synthase, isocitrate lyase, enolase, HSP60-like protein, and an uncharacterized protein (thioredoxin-like superfamily) [ 54 , 70 , 87 , 88 , 89 , 90 , 91 , 92 , 93 ]. Proteins included in group 2 are antigens that already have been described in human PCM, such as triosephosphate isomerase, glyceraldehyde-3-phosphate dehydrogenase, fructose-bisphosphate aldolase [ 70 ], or Paracoccidioides antigens that already have been related to eliciting a humoral immune response in BALB/c mice, such as transketolase, HSP60-like protein, and isocitrate lyase (all shared with PS3) [ 71 ].…”

Metabolic Adaptation of Paracoccidioides brasiliensis in Response to in vitro Copper Deprivation

“…Biological triplicates of protein samples from yeast cells were labeled with iTRAQ as previously described ( Araújo et al, 2019 ). Desalting of the samples was performed, and 50 μg of the material was resuspended in 17 μL of 300 mM TEAB.…”

Propionate metabolism in a human pathogenic fungus: proteomic and biochemical analyses

“…Transcriptomic and proteomic approaches suggested that mycelium oxidizes glucose by an aerobic route while yeasts present a more fermentative glucose metabolism in P. lutzii (Bastos et al 2007;Felipe et al 2005;Rezende et al 2011). However, proteomic data show the reverse for P. brasiliensis (Araujo et al 2019). Also, enzymes of the methylcitrate and glyoxylate cycles were induced during mycelium to yeast transition (Rezende et al 2011).…”

“…Differential gene expression studies have shown that P. lutzii yeast cells employ fermentative metabolism while mycelial cells use aerobic routes for energy production (Felipe et al 2005), which was subsequently confirmed by proteomic studies (Rezende et al 2011). In contrast, P. brasiliensis (PB18) utilizes a more aerobic metabolism in yeast cells compared to hyphae (Araujo et al 2019). Further, during mycelium-to-yeast transition metabolic pathways change to support membrane and cell wall remodeling (Bastos et al 2007).…”