Aspergillus fumigatus Morphology and Cell Wall Analysis

Growth of the A. fumigatus strains was carried out onto solid CM or MM at 37 °C. For morphological observation, 2 × 10⁸ spores were inoculated into 200 ml liquid CM and incubated at 37 °C at 200 rpm, then stained with 10 μg/ml Calcofluor white (Sigma) and 1 mg/ml 4′-6-diamidino-2-phenylindole (DAPI; Sigma) as previously described^{36 (link)}, prior to fluorescence microscopy using a Zeiss Imager A2 (Zeiss, Japan). For propidium iodide (PI) staining, 2 × 10⁸ conidia were inoculated in 200 ml of CM and incubated at 37 °C with 200 rpm. The mycelia were collected, stained with PI, and then examined under the fluorescence microscope.
For scanning electron microscopy (SEM) or transmission electron microscopy (TEM), the mycelia cultivated in liquid CM at 37 °C were collected and fixed as previously described^{11 (link),36 (link)} prior to examining the sections with a Tecnai Spirit (120 kV) transmission electron microscope (FEI, USA). For chemical analysis of the cell wall, cell wall components were isolated and determined as previously described^{11 (link)}.