The malate synthase of Paracoccidioides brasiliensis is a linked surface protein that behaves as an anchorless adhesin.
BACKGROUND
The pathogenic fungus Paracoccidioides brasiliensis is the agent of paracoccidioidomycosis (PCM). This is a pulmonary mycosis acquired by inhalation of fungal airborne propagules that can 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 the host, P. brasiliensis may use the glyoxylate cycle for intracellular survival.


RESULTS
Here, we provide evidence that the malate synthase of P. brasiliensis (PbMLS) is located on the fungal cell surface, and is secreted. PbMLS was overexpressed in Escherichia coli, and polyclonal antibody was obtained against this protein. By using Confocal Laser Scanning Microscopy, PbMLS was detected in the cytoplasm and in the cell wall of the mother, but mainly of budding cells of the P. brasiliensis yeast phase. PbMLSr and its respective polyclonal antibody produced against this protein inhibited the interaction of P. brasiliensis with in vitro cultured epithelial cells A549.


CONCLUSIONS
These observations indicated that cell wall-associated PbMLS could be mediating the binding of fungal cells to the host, thus contributing to the adhesion of fungus to host tissues and to the dissemination of infection, behaving as an anchorless adhesin.
da Silva Neto
Benedito Rodrigues
BR
Laboratório de Biologia Molecular, Departamento de Bioquímica e Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, 74001-970 Goiânia, GO, Brazil.
de Fátima da Silva
Julhiany
J
Mendes-Giannini
Maria José Soares
MJ
Lenzi
Henrique Leonel
HL
de Almeida Soares
Célia Maria
CM
Pereira
Maristela
M
D000908:Antibodies, Fungal / Q000276:immunology; D019921:Biotinylation; D002460:Cell Line; D002473:Cell Wall / Q000201:enzymology*; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D005656:Fungal Proteins / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D008292:Malate Synthase / Q000276:immunology / Q000378:metabolism*; D018613:Microscopy, Confocal; D010228:Paracoccidioides / Q000201:enzymology* / Q000235:genetics; D011485:Protein Binding; D011994:Recombinant Proteins / Q000378:metabolism
D000908:Antibodies, Fungal; D016326:Extracellular Matrix Proteins; D005656:Fungal Proteins; D011994:Recombinant Proteins; D008292:Malate Synthase