1,8-Dihydroxynaphthalene (DHN) melanin provides unequal protection to black fungi Knufia petricola and Cryomyces antarcticus from UV-B radiation ...

• Main Authors: Catanzaro, Ilaria, Gorbushina, Anna A., Onofri, Silvano, Schumacher, Julia
• Format: Text
• Language: English
• Published: Freie Universität Berlin 2024
• Subjects: black fungi; UV-B radiation; protection; Mikroorganismen, Pilze, Algen; Antarc*; antarcticus
• Online Access: https://dx.doi.org/10.17169/refubium-45947; https://refubium.fu-berlin.de/handle/fub188/46235

Black fungi on rock surfaces endure a spectrum of abiotic stresses, including UV radiation. Their ability to tolerate extreme conditions is attributed to the convergent evolution of adaptive traits, primarily highly melanized cell walls. However, studies on fungal melanins have not provided univocal results on their photoprotective functions. Here, we investigated whether the black fungi Knufia petricola and Cryomyces antarcticus only use DHN melanin or may employ alternative mechanisms to counteract UV-induced damage. For this, melanized wild types and non-melanized Δpks1 mutants were exposed to different doses of UV-B (312 nm) followed by incubation in constant darkness or in light–dark cycles to allow light-dependent DNA repair by photolyases (photoreactivation). C. antarcticus could tolerate higher UV-B doses but was sensitive to white light, whereas K. petricola showed the opposite trend. DHN melanin provided UV-B protection in C. antarcticus, whereas the same pigment or even carotenoids proved ...