Arctic Life/Arctic Fungi

From Arctic Bioscan Wiki
An example of an Arctic fungi, the Arctic basidiomycete

Fungi are often classified as plants, yet they have no roots, shoots, stems, or leaves and some live entirely in the dark. Fungi also lack chlorophyll, which means they cannot produce their own food as plants do. In fact, fungi are heterotrophic organisms, and create energy by releasing enzymes from their cells to break down organic matter. Fungi possess a branched, tubular body, and reproduce by means of spores. These characteristics are so distinctive that fungi have been placed in a taxonomic group by themselves, the Kingdom Fungi. Although there are two major groups of fungi, protoctistan and eumycotan, only the eumycotan or "true" fungi will be discussed here.

There is little awareness of the importance of fungi in everyday life. For instance, the toast you ate for breakfast, the blue cheese in your salad dressing at lunch, the soy sauce on your rice at dinner, and the night cap you had before bed, were all made possible by fungi. Antibiotics, such as penicillin, are also derived from fungi and some fungi contain enzymes that are used in detergents. Fungal biodiversity can be used as a bioindicator of environmental changes resulting from atmospheric and terrestrial pollution. Fungi also play a significant role in maintaining the dynamic equilibrium within fragile northern ecosystems as major decomposers, symbionts, and parasites.

Relatively few studies have been done on the fungi which inhabit the Canadian Arctic. Extensive accounts of the rusts (Uredinales) and other parasitic fungi of Arctic Canada have been published, and microfungi have been studied in a few locations, but the larger mushroom species remain poorly documented. In fact, the field of mycology remains largely unexplored and open for discovery in the Canadian High Arctic.

Adaptations

An Arctic mushroom. Photo courtesy of Marine Science.

Like the animals and plants which occur in the Arctic, polar fungi have evolved physiological and morphological characteristics to aid their survival. Instant cold-hardiness is a characteristic common to all species of fungi that grow in the Arctic. Periodic hard frosts in mid-summer make it imperative for polar fungi to be able to resume growth immediately in the brief growing season. To survive low temperatures fungi produce substances, such as glycerol, proline, and trehalose, which act as cryoprotectants. These solutes protect hyphal cells from potentially lethal shrinkage and ice crystal formation.

In the polar deserts of Canada's High Arctic, the lack of water is a constant threat to survival. However, xerophilic fungi are capable of survival and growth under these conditions. In fact, some of these fungi can grow and reproduce with water activity (water available in the substrate for use) as low as 0.65 (most vascular plants wilt when water activity falls below 0.98). This tolerance of water scarcity is aided by compounds such as proline, glycerol, and mannitol, which enable enzymes to function efficiently under water stress.

The third major threat to survival in the Arctic is ultraviolet (UV) radiation from the sun. UV-B radiation splits the water molecules in hyphal cells into free radicals, which can damage DNA. To avoid this effect, some arctic fungi have developed a mycelium and spores with dark pigmentation, which UV-B rays cannot readily penetrate. Other arctic fungi have developed mechanisms enabling the rapid repair of damaged DNA.

To learn more about polar fungi adaptations, please browse below.

Cool Facts

The Fungi kingdom contains some of the most interesting organisms on our planet. This is especially true in the Arctic, where harsh living conditions have resulted in super cool fungi facts. Please browse below to learn fun trivia about polar fungi.

Fungal Biology

The Kingdom fungi is extremely biologically unique, containing at least 100,000 identified species.[1] Although, it is speculated that approximately 5.1 million fungal species exist, as of 2017.[1]

To explore intriguing biological knowledge regarding the kingdom fungi, please browse below.

Northern Fungi

Although not enough work has been done to provide an accurate species count, it is known that hundreds of different fungal species occur in tundra habitats.

Please browse the fungal classes below to learn about different species of Arctic fungi!

References

  1. 1.0 1.1 Peralta, Rosane Marina; da Silva, Bruna Polacchineda; Gomes Côrrea, Rúbia Carvalho; Kato, Camila Gabriel; Vicente Seixas, Flávio Augusto; Bracht, Adelar (2017). Enzymes from Basidiomycetes—Peculiar and Efficient Tools for Biotechnology. Maringa, Brazil: Academic Press. p. 119-149.