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Abstract This study investigates the chemical inhibition of asexual development in Aspergillus nidulans to enhance the mechanical properties of mycelial materials. We hypothesized that suppressing conidiation using the ornithine decarboxylase inhibitor α-difluoromethylornithine (DFMO) would increase material strength by inhibiting asexual development, promoting denser hyphal packing. Mycelial materials were grown in DFMO concentrations (0, 0.05, 0.5, and 5 mM), and conidiation and ultimate tensile strength (UTS) were measured. Results showed a dose-dependent reduction in conidiation, with significant decreases at all DFMO levels (P ≤ 0.05). While lower DFMO concentrations (0.05 and 0.5 mM) did not significantly alter UTS, 5 mM DFMO treatment doubled the material’s tensile strength compared to controls (P ≤ 0.05). Scanning electron microscopy confirmed reduced developmental structures in DFMO-treated samples, supporting the hypothesis. The non-linear relationship between conidiation suppression and strength improvement suggests additional mechanisms, such as hyphal morphology or cell wall changes, may contribute. These findings demonstrate that chemical modulation of fungal development can rationally tune mycelial material properties, offering a systematic approach for biomaterial engineering.
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This content will become publicly available on April 1, 2026
The impact of fungal developmental structures on mechanical properties of mycelial materials
ABSTRACT This study explores how suppressing asexual development inAspergillus nidulansenhances the mechanical properties of mycelial materials. Using four aconidial mutants(ΔbrlA, ΔflbA, ΔfluG, andfadAG42R) that lack asexual development and a control strain (A28) that undergoes typical asexual development, we found that the absence of asexual development significantly improves mechanical strength. All mutants exhibited higher ultimate tensile strength (UTS) than the control, with ΔfluGand ΔbrlA(fluffy nonsporulating, FNS phenotype) showing the highest UTS. Additionally,fadAG42Rand ΔflbA(fluffy autolytic dominant, FAD phenotype) demonstrated significantly higher strain at failure (SF), linked to increased autolysis and lower dry cell mass compared to the control and FNS mutants. Solid-state NMR analysis revealed that autolysis in FAD mutants disrupts galactofuranose-related metabolic processes, altering cell wall composition and contributing to higher elasticity. These findings suggest that suppressing asexual development enhances mycelial material strength, while autolysis mechanisms influence elasticity. This research highlights the potential for genetic manipulation in fungi to engineer advanced mycelial-based materials with tailored mechanical properties.
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- Award ID(s):
- 2006189
- PAR ID:
- 10597858
- Publisher / Repository:
- bioRxiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- bioRxiv
- Sponsoring Org:
- National Science Foundation
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