title: Cold adaptation of fungi obtained from soil and lake sediment in the Skarvsnes ice-free area, Antarctica.
abstract: A total of 71 isolates were collected from lake sediment and soil surrounding lakes in the Skarvsnes area, Antarctica. Based on ITS region sequence similarity, these isolates were classified to 10 genera. Twenty-three isolates were categorized as ascomycetous fungi from five genera (Embellisia, Phoma, Geomyces, Tetracladium or Thelebolus) and 48 isolates were categorized as basidiomycetous fungi in five genera (Mrakia, Cryptococcus, Dioszegia, Rhodotorula or Leucosporidium). Thirty-five percent of culturable fungi were of the genus Mrakia. Eighteen isolates from eight genera were selected and tested for both antifreeze activity and capacity for growth under temperatures ranging from -1 to 25 °C. Rhodotorula sp. NHT-2 possessed a high degree of sequence homology with R. gracialis, while Leucosporidium sp. BSS-1 possessed a high degree of sequence homology with Leu. antarcticum (Glaciozyma antarctica), and these two isolates demonstrated antifreeze activity. All isolates examined were capable of growth at -1 °C. Mrakia spp., while capable of growth at -1 °C, did not demonstrate any antifreeze activity and exhibited only limited secretion of extracellular polysaccharides. Species of the genus Mrakia possessed high amounts of unsaturated fatty acids, suggesting that members of this genus have adapted to cold environments by increasing their membrane fluidity.
authors.affiliation: Biomass Refinery Research Center (BRRC), National Institute of Advanced Industrial Science and Technology (AIST), Hiroshima, Japan.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Tsuji
authors.forename: Seiichi
authors.initials: S
authors.lastname: Fujiu
authors.forename: Nan
authors.initials: N
authors.lastname: Xiao
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hanada
authors.forename: Sakae
authors.initials: S
authors.lastname: Kudoh
authors.forename: Hidemasa
authors.initials: H
authors.lastname: Kondo
authors.forename: Sakae
authors.initials: S
authors.lastname: Tsuda
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Hoshino
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000864:Antarctic Regions; D001203:Ascomycota / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology*; D001487:Basidiomycota / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D003080:Cold Temperature; D058639:Cold-Shock Response / Q000235:genetics / Q000502:physiology; D004271:DNA, Fungal / Q000032:analysis / Q000235:genetics; D019015:Geologic Sediments / Q000382:microbiology*; D012988:Soil Microbiology
chemical_list: D004271:DNA, Fungal
keywords: Basidiomycota; Skarvsnes ice-free area; biodiversity; cold adaptation; cryophilic fungi