Aspergillus fumigatus is the most important air-borne human fungal pathogen. The genome of this filamentous fungus exhibits far more gene clusters predicted to encode secondary metabolites than compounds known. Because these unidentified metabolites could have important biological functions and possibly represent drug candidates, it is desirable to activate their often silent biosyntheses. Our aim was to mimic physiological conditions under which secondary metabolite gene clusters could be activated. Previously, we demonstrated activation of a silent secondary metabolite gene cluster of Aspergillus nidulans by co-cultivation with Streptomyces rapamycinicus which led to formation of orsellinic and lecanoric acid. Interestingly, as shown here, the bacterium is also able to activate silent gene clusters in the human-pathogenic fungus A. fumigatus. Co-culturing of A. fumigatus with this streptomycete triggered the specific activation of a so far silent fungal secondary metabolite gene cluster leading to the production of a novel secondary metabolite.
Full conference title:
- Asperfest 9 (2012)