Microscopic Visualization of A. niger

Different cultivation techniques were applied for microscopy. Cultivation for cLSM microscopy of A. niger was performed as described recently (Kwon et al., 2014 (link)). In brief, spores were spotted in MM plates, supplemented with different concentrations of doxycycline when needed and incubated at 22°C for 2 days, following cutting out of the colony and placing it upside down into a glass bottom petri dish (Kwon et al., 2014 (link)). Liquid MM medium (supplemented with the same concentration of doxycycline which was present in the MM plate) was added and cells were incubated at 22°C until they resumed growth. Fluorescence and DIC images were taken using an inverted TCS SP8 (Leica, Germany). For fluorescence microscopy, cultivation was performed as described earlier (Fiedler et al., 2014 (link)). In brief, cover slides were placed on the bottom of a Petri dish containing 5 ml MM medium (supplemented with 100 mM MES pH6.5 and different concentrations of doxycycline when needed), inoculated with 1 × 10⁵ spores/ml and cultivated at 28°C for 12 h. Images were acquired using a DMI6000 fluorescence microscope (Leica, Germany).