PT  - JOURNAL ARTICLE
AU  - Erin C. Carr
AU  - Quin Barton
AU  - Sarah Grambo
AU  - Mitchell Sullivan
AU  - Cecile M. Renfro
AU  - Alan Kuo
AU  - Jasmyn Pangilinan
AU  - Anna Lipzen
AU  - Keykhosrow Keymanesh
AU  - Emily Savage
AU  - Kerrie Barry
AU  - Igor V. Grigoriev
AU  - Wayne R. Riekhof
AU  - Steven D. Harris
TI  - Deciphering the potential niche of novel black yeast fungal isolates in a biological soil crust based on genomes, phenotyping, and melanin regulation
AID  - 10.1101/2021.12.03.471027
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.12.03.471027
4099  - http://biorxiv.org/content/early/2021/12/04/2021.12.03.471027.short
4100  - http://biorxiv.org/content/early/2021/12/04/2021.12.03.471027.full
AB  - Black yeasts are polyextremotolerant fungi that contain high amounts of melanin in their cell wall and maintain a primarily yeast form. These fungi grow in xeric, nutrient deplete environments which implies that they require highly flexible metabolisms and the ability to form lichen-like mutualisms with nearby algae and bacteria. However, the exact ecological niche and interactions between these fungi and their surrounding community is not well understood. We have isolated two novel black yeast fungi of the genus Exophiala: JF 03-3F “Goopy” E. viscosium and JF 03-4F “Slimy” E. limosus, which are from dryland biological soil crusts. A combination of whole genome sequencing and various phenotyping experiments have been performed on these isolates to determine their fundamental niches within the biological soil crust consortium. Our results reveal that these Exophiala spp. are capable of utilizing a wide variety of carbon and nitrogen sources potentially from symbiotic microbes, they can withstand many abiotic stresses, and can potentially provide UV resistance to the crust community in the form of secreted melanin. Besides the identification of two novel species within the genus Exophiala, our study also provides new insight into the production and regulation of melanin in extremotolerant fungi.Competing Interest StatementThe authors have declared no competing interest.