Antarctic Permafrost: An Unexplored Fungal Microhabitat at the Edge of Life

Abstract

The Antarctic continent represents one of the most primal environments in the world. The fungal communities found in this region are complex and have the ability to survive under extreme conditions of dehydration, frequent freeze-thaw cycles, low nutrient concentration, low temperatures, and high exposure to ultraviolet radiation. Current studies on Antarctic fungi are, in its majority, related to soil fungi. However, studies on the fungal community present in permafrost (soils that are permanently frozen for at least 2 consecutive years) are scarce, especially when compared to the number of studies on Arctic permafrost. Therefore, this chapter aims to compile all documented data related to Antarctic permafrost fungi and the importance of permafrost as a substrate that can host a cryptic and unique community of Antarctic fungi. The predominant taxa found in Antarctic permafrost belong to the phylum Ascomycota, followed by taxa belonging to the phyla Basidiomycota,Mortierellomycota, and Mucoromycota. Thus far, 32 families, 45 genera, and 70 species of fungi have been identified in the Antarctic permafrost. Among the 70 fungal species, Cladosporium herbarum has the widest geographic distribution and has been isolated from different regions of Antarctica. Although there are few studies on the fungal diversity in the Antarctic permafrost, this type of frozen soil is of considerable importance to the cold regions of the planet because of the effects of global climate change, especially the potential effect of global warming in the next few years. Microorganisms currently “trapped” in permafrost, possibly in their latent forms, could eventually be dispersed to other regions of the globe. Additionally, undiscovered fungi present in the Antarctic permafrost may represent promising sources of bioproducts for use in biotechnological processes.