Back to the Salt Mines: Genome and Transcriptome Comparisons of the Halophilic Fungus and Its Halotolerant Relative .

Salt mines are among the most extreme environments as they combine darkness, low nutrient availability, and hypersaline conditions. Based on comparative genomics and transcriptomics, we describe in this work the adaptive strategies of the true halophilic fungus , found in a salt mine in Austria, and compare this strain to the ex-type halotolerant fungal strain . On a genomic level, exhibits a reduced genome size compared to , as well as a contraction of genes involved in transport processes. The proteome of exhibits an increased proportion of alanine, glycine, and proline compared to the proteome of non-halophilic species. Transcriptome analyses of both strains growing at 5% and 20% NaCl show that regulates three-times fewer genes than in order to adapt to the higher salt concentration. In , the increased osmotic stress impacted processes related to translation, transcription, transport, and energy. In contrast, membrane-related and lignolytic proteins were significantly affected in .