Isolation, Identification and Proteolytic Activity of Filamentous Fungi from Alaska

From two soil samples taken in the Denali National Park and Preserve, Alaska, 28 filamentous fungi were isolated on selective media. A total of 28 fungal isolates were identified. The most widespread fungal species belonged to the genera Aspergillus, Mucor, Tolypocladium, Daldinia, and Pseudogymnoascus. A phylogenetic tree was constructed with the neighbour-joining method using the Kimura two-parameter model included in the MEGA 4 software. The linear growth of the fungal isolates was measured after 10 days of conidiospore cultivation on agar plates at temperatures of 4, 10, and 25°C. The majority of the fungal strains identified in this study were mesophiles. All isolated strains were screened for proteolytic activity. Among them, seven strains showed high protease activity. These findings expand our knowledge about fungal biodiversity in harsh cold environments as well as the enzyme production by extremophilic fungi.