2024 AIChE Annual Meeting
Characterizing the Aspergillus Nidulans Kinase Deletion Library for Differential Septation in Response to Cell Wall Stress
Beneficial filamentous fungi are used prevalently in the bioprocessing industry, producing high-value commercial products, while pathogenic species cause significant detriment to the health of crops and humans. Understanding the mechanisms which control the biosynthesis and repair of the fungal cell wall, a critical structure for the survival of fungi, will help us better interact with fungi in diverse contexts. For example, we could modify the cell wall to optimize production goals in industry or identify novel targets to improve the efficacy of antifungal drugs. To maintain cell wall integrity, filamentous fungi employ complex signaling pathways, predominantly mediated by protein kinases. However, many of the 98 nonessential protein kinases in the model fungus Aspergillus nidulans have unknown function. Previous research in our lab has shown septation is important for surviving cell wall stress, and we hypothesize that many of the 98 kinases will have connections to both the Septation Initiation Network (SIN) and the Cell Wall Integrity (CWI) signaling pathway. To test this hypothesis, the 98 strains from the A. nidulans kinase deletion library, each lacking one specific kinase gene, were grown for 16 hours under two conditions: with and without micafungin, a cell-wall perturbant triggering septation. Fluorescent microscopy was used to capture images of the fungal cells to determine extent of growth and number of septa formed. By comparing the phenotypes of the mutant strains to an isogenic control strain, the involvement of the various kinases in responding to wall stress can be inferred.