Virulence genes and molecules of Aspergillus fumigatus

Aspergillus fumigatus is one of the most common airborne fungal pathogens causing invasive aspergillosis in immunocompromised patients.Unlike most primary pathogens,which possess virulence traits that developed in association with a host organism,evidence suggests that the virulence of Aspergillus fumigatus has evolved from the resistance to the adverse factors encountered in nature.These features enhance the overall competitiveness of the organism in its environmental niche but are also thought to promote its growth and survival in a human host.Although many of the genes responsible for these characteristics do not fit into the classical definition of a virulence factor,they are important to the pathogenesis of aspergillosis,including the genes involved in thermotolerant growth,cell wall barrier,damaging products secretion,signaling and responding to environment,nutritional requirements,and so on.