Malato sintase de Paracoccidioides brasiliensis é uma proteína ligada à superfície que se comporta como uma anchorless adesina

Abstract

The pathogenic fungus Paracoccidioides brasiliensis causative of Paracoccidioidomycosis (PCM), a pulmonary mycose acquired by inhalation of fungal airborne propagules, which may disseminate to several organs and tissues leading to a severe form of the disease. Adhesion and invasion to host cells are essential steps involved in the internalization and dissemination of pathogens. Inside host, P. brasiliensis use the glyoxylate cycle for intracellular survival. Here, we provide evidence that malate synthase of P. brasiliensis (PbMLS) is localized on the cell wall, and is secreted. PbMLS was overexpressed in Escherichia coli, and polyclonal antibody against this protein was obtained. By using Confocal Laser Scanning Microscopy and Western blot analysis, PbMLS was detected in the cytoplasm and the cell wall of the yeast phase of P. brasiliensis of mother and bud yeast cells. PbMLSr and the respective polyclonal antibody produced against this protein inhibited the interaction of P. brasiliensis to in vitro cultured epithelial cells A549. These observations indicated that cell wall-associated MLS of P. brasiliensis could be mediating the binding of fungal cells, thus contributing to the adhesion of fungus to host tissues and to the dissemination of infection.