SRA

Soil dwelling Aspergillus fungi possess the versatile metabolic capability to utilize complex organic compounds which are toxic to humans, yet the mechanisms they employ remain largely unknown. Benzo(a)pyrene is a common carcinogenic contaminant, posing a significant concern for human health. Here, we report that Aspergillus fungi can degrade benzo(a)pyrene effectively. In Aspergillus nidulans, exposure to benzo(a)pyrene results in transcriptomic and metabolic changes associated with cellular growth and energy generation, implying that the fungus utilizes benzo(a)pyrene as a food. Importantly, we identify and characterize the conserved bapA gene encoding a cytochrome P450 monooxygenase that exerts the first step in the degradation of benzo(a)pyrene. We further demonstrate that the fungal NF-?B-type global regulators VeA and VelB are required for benzo(a)pyrene degradation in A. nidulans, which occurs through expression control of bapA in response to nutrient limitation. Our study illuminates fundamental knowledge of fungal benzo(a)pyrene metabolism and provides novel insights into enhancing bioremediation potential. Overall design: Aspergillus nidulans hyphae were incubated in 0.1% glucose media with 200 µM benzo(a)pyrene or solvent only control (DMSO) and samples were taken at 6, 24, and 48 hours post incubation. Timepoint zero represents spore inoculation in 1% glucose media and growth for 18 hours. Transcripts were sequenced using Illumina HiSeq2500