A phylogenetic approach to explore the Aspergillus fumigatus conidial surfome and its role in pathogenesis

Aspergillus fumigatus is the most important pulmonary fungal pathogen and is able to cause several diseases collectively called aspergillosis. Conidia is the most important infection structure making the initial contact with the human host. Here, we used a phylogenomic approach comparing proteins present in the A. fumigatus conidial surface, two closely related non-pathogenic species A. fischeri and A. oerlinghausenensis, and the far-related pathogenic A. lentulus. We were able to identify 62 proteins specifically expressed on A. fumigatus conidial surface. We deleted 42 of the encoding-genes and observed that many of them have altered susceptibility to macrophage killing, penetration and damage to epithelial cells, and cytokine production. We demonstrated that one of these genes encoding a glycosylasparaginase is modulating IL-1β levels and is important for the infection in an immunocompetent murine model. Our results provide opportunities for characterizing A. fumigatus effectors important for evasion and modulation of the immune response.