Home • Exophiala viscosa JF 03-4F Slimy CBS 148802 v1.0
Eurotiomycetes sp. JF 03-4F Slimy
Figure 1: JF 03-4F “Slimy” plate image. This fungus was grown on an MEA plate for 10 days when this photo was taken. It’s highly melanized cell wall is easily observed by the dark black color of its colonies. It forms smooth, shiny, circular colonies that are easily spread across a plate. Photo credit: Christian Elowsky
Eurotiomycetes sp. JF 03-4F Slimy
Figure 2: JF 03-4F “Slimy” microscopy image with a 60x objective lens. Morphology of this isolate is slightly elongated yeast cells, as observed in this image. Growth conditions of this isolate was on MEA for 5 days of growth, then the fungi was scrapped off and diluted in water to obtain a planktonic cell solution for imaging. Thick cell walls that are typical of black yeast fungi, circular lipid bodies, and large vacuoles are observed in this image. Photo credit: Christian Elowsky

JF 03-4F Slimy

JF 03-4F “Slimy” is an unknown black yeast fungal culture whose highest hit on the NCBI database is Eurotiomycetes sp. Voucher ARIZ: SR0058 (KP991853.1); 97% matching. Black yeast fungi are recognized as polyextremotolerant fungi because of their high resistance to many stressors (Gostinčar et al., 2012). In addition, the name “black yeast fungi” refers to both their morphology and their highly melanized cell wall (Gostinčar et al., 2012). This black yeast was isolated as part of a broader survey of fungal-algal associations in dryland Biological Soil Crusts (BSCs). It was recovered from a BSC community located in Jackman Flats Provincial Park (B.C., Canada). JF 03-4F possesses a simplified morphology that does not include the presence of pseudohyphae or true hyphae. It does have difficulty spreading in water due to a highly hydrophobic cell surface. No teleomorphic state has yet been observed for JF 03-4F but that is typical of black yeast fungi (Untereriner et al., 1995). Extensive phenotyping shows that this isolate can use all standard nitrogen sources to support growth. However, it is deficient in the use of several carbon sources including the sugar alcohol Mannitol. Moreover, JF 03-4F is resistant to several metals, but not nickel or cadmium. It’s optimal growth temperature is 22°C, although it was able to grow at 27°C as well. Growth at 37°C, 42°C, and 4°C was severely stunted compared to 22°C, suggesting that growth above 27°C is not optimal.


    •    Gostinčar, C., Muggia, L., & Grube, M. (2012). Polyextremotolerant black fungi: oligotrophism, adaptive potential, and a link to lichen symbioses. Frontiers in microbiology, 3, 390.
    •    Untereiner, W. A., Straus, N. A., & Malloch, D. (1995). A molecular-morphotaxonomic approach to the systematics of the Herpotrichiellaceae and allied black yeasts. Mycological Research, 99(8), 897-913.

Genome Reference(s)