The hydrolase PbHAD32 participates in the adherence of Paracoccidioides brasiliensis conidia to epithelial lung cells

Abstract

Adherence of the dimorphic pathogenic fungus Paracoccidioides brasiliensis to lung epithelial cells is considered an essential event for the establishment of infection. We have previously shown that the PbHAD32 hydrolase is important in this early stage of the host-P. brasiliensis yeast cells interaction. The aim of this study was to further elucidate the role of PbHAD32 in conidial thermodimorphism and their interaction with lung epithelial cells. Analysis of the PbHAD32 gene expression revealed higher mRNA levels during the conidia to mycelia (C-M) germination when compared to the conidia to yeast (C-Y) transition. Moreover, PbHAD32 was consistently expressed at higher levels upon infection of lung epithelial cells, but to a greater extent when conidia germinated to produce mycelia. Interestingly, at this particular transitional stage, more conidia adhered to epithelial cells than when they were transiting to the yeast form. Altogether our data further corroborates the importance of PbHAD32 during initial adherence to host cells and suggest that the 32-KDa hydrolase may also participate at different stages of the C-M and C-Y conversions.

P. brasiliensis Virulence Is Affected by SconC, the Negative Regulator of Inorganic Sulfur Assimilation

“…brasiliensis and its degree of virulence, including CDC42 [26,32], GP43 [33-35], HAD32 [36] and AOX [37]. However, the research on P.…”

Decreased expression of 14-3-3 inParacoccidioides brasiliensisconfirms its involvement in fungal pathogenesis

“…[29][30][31] Previous studies focused on elucidating the function of the 14-3-3 protein in the pathogenesis of P. brasiliensis. 27,28 Those studies were limited to the use of the recombinant 14-3-3 protein and the anti-14-3-3 antibody, and they therefore indirectly explored the role of 14-3-3 without manipulating gene expression.…”

Paracoccidioides Species Complex: Ecology, Phylogeny, Sexual Reproduction, and Virulence

“…The ability of fungal cells to adhere to host cells is also vital for the initial steps of the infection process. Phospholipase B, involved in the fungus-macrophage interaction, and PbHad32p, a hydrolase involved in adherence to host cells, have both been proposed to be important for the initial steps of the virulence process [27], [28]. The genes encoding glyceraldehyde-3-phosphate-dehydrogenase (GAPDH), identified as a cell wall–associated host-adhesion molecule in Paracoccidioides , and enolase, which binds to fibronectin, have also been linked to the initial adhesion of the fungus to lung epithelial cells and alveolar macrophages upon infection [29].…”