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Transcriptional analysis of developing Aspergillus fumigatus biofilms reveals metabolic shifts required for biofilm maintenance

ABSTRACT: Aspergillus fumigatus is a filamentous fungus found in compost and soil that can cause invasive and/or chronic disease in a broad spectrum of individuals. Diagnosis and aspergillosis treatment often occur during late stages of infection when A. fumigatus has formed dense networks of hyphae within the lung. These dense hyphal networks have hallmark characteristics of a microbial biofilm, a fungal mode of growth that can be recapitulated in vitro using a static, submerged biofilm culture model. A. fumigatus biofilms in this model are multicellular, encased in a thick ECM layer, and have reduced susceptibility to contemporary antifungal drugs. This reduced susceptibility is hypothesized to be in part due to spatial cellular quiescence in the biofilm that likely occurs in response to regions of low oxygen that form during biofilm development. The mechanisms underlying filamentous fungal cell physiology at different stages of biofilm development remain to be defined. Here, we utilized an RNA sequencing approach to evaluate changes in transcripts during A. fumigatus biofilm development. These analyses revealed an increase in transcripts associated with fermentation and a concomitant decrease in oxidative phosphorylation related transcripts. Further studies revealed that ethanol fermentation is important for mature biofilm biomass maintenance. Correspondingly, a gene predicted to be involved in mitigating ethanol mediated membrane stress was observed to also be required for mature biofilm biomass maintenance. Taken together, these data suggest changes in A. fumigatus carbon utilization as biofilms develop impact the ability to maintain a fully mature biofilm.

ORGANISM(S): Aspergillus fumigatus

PROVIDER: GSE298422 | GEO | 2025/06/03

REPOSITORIES: GEO

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Transcriptional analysis of developing Aspergillus fumigatus biofilms reveals metabolic shifts required for biofilm maintenance

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