3 results for Arenz, Brett E.

  • Screening fungi isolated from historic Discovery Hut on Ross Island, Antarctica for cellulose degradation

    Duncan, Shona Margaret; Minasaki, Ryuji; Farrell, Roberta L.; Thwaites, Joanne M.; Held, Benjamin W.; Arenz, Brett E.; Jurgens, Joel Allan; Blanchette, Robert A. (2008)

    Journal article
    University of Waikato

    To survive in Antarctica, early explorers of Antarctica's Heroic Age erected wooden buildings and brought in large quantities of supplies. The introduction of wood and other organic materials may have provided new nutrient sources for fungi that were indigenous to Antarctica or were brought in with the materials. From 30 samples taken from Discovery Hut, 156 filamentous fungi were isolated on selective media. Of these, 108 were screened for hydrolytic activity on carboxymethyl cellulose, of which 29 demonstrated activities. Endo-1, 4-β-glucanase activity was confirmed in the extracellular supernatant from seven isolates when grown at 4°C, and also when they were grown at 15°C. Cladosporium oxysporum and Geomyces sp. were shown to grow on a variety of synthetic cellulose substrates and to use cellulose as a nutrient source at temperate and cold temperatures. The research findings from the present study demonstrate that Antarctic filamentous fungi isolated from a variety of substrates (wood, straw, and food stuffs) are capable of cellulose degradation and can grow well at low temperatures.

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  • An Antarctic hot spot for Fungi at Shackleton's Historic Hut on Cape Royds

    Blanchette, Robert A.; Held, Benjamin W.; Arenz, Brett E.; Jurgens, Joel Allan; Baltes, Nicolas; Duncan, Shona Margaret; Farrell, Roberta L. (2010)

    Journal article
    University of Waikato

    The historic expedition huts located in the Ross Sea Region of the Antarctic and the thousands of artifacts left behind by the early explorers represent important cultural heritage from the “Heroic Era” of Polar exploration. The hut at Cape Royds built by Ernest Shackleton and members of the 1907–1908 British Antarctic Expedition has survived the extreme Antarctic environment for over 100 years, but recent studies have shown many forms of deterioration are causing serious problems, and microbial degradation is evident in the historic wood. Conservation work to reduce moisture at the hut required removal of fodder, wood, and many different types of organic materials from the stables area on the north side of the structure allowing large numbers of samples to be obtained for these investigations. In addition, wood from historic food storage boxes exposed in a ravine adjacent to the hut were also sampled. Fungi were cultured on several different media, and pure cultures were obtained and identified by sequencing of the internal transcribed spacer region of rDNA. From the 69 cultures of filamentous fungi obtained, the most predominant genera were Cadophora (44%) followed by Thielavia (17%) and Geomyces (15%). Other fungi found included Cladosporium, Chaetomium, and isolates identified as being in Pezizomycotina, Onygenales, Nectriaceae, and others. No filamentous basidiomycetes were found. Phylogenetic analyses of the Cadophora species showed great species diversity present revealing Cadophora malorum, Cadophora luteo-olivacea, Cadophora fastigiata, as well as Cadophora sp. 4E71-1, a C. malorum-like species, and Cadophora sp. 7R16-1, a C. fastigiata-like species. Scanning electron microscopy showed extensive decay was present in the wood samples with type 1 and type 2 forms of soft rot evident in pine and birch wood, respectively. Fungi causing decay in the historic wooden structures and artifacts are of great concern, and this investigation provides insight into the identity and species diversity of fungi found at the site. The historic woods and other organic materials at this site represent a large input of carbon into the Antarctic environment. This as well as nutrient additions from the nearby Adélie penguin (Pygoscelis adeliae) colony and favorable conditions for fungal growth at Cape Royds appear responsible for the significant fungal diversity, and where extensive decay is taking place in wood in contact with the ground.

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  • Introduced and indigenous fungi of the Ross Island historic huts and pristine areas of

    Farrell, Roberta L.; Arenz, Brett E.; Duncan, Shona Margaret; Held, Benjamin W.; Jurgens, Joel Allan; Blanchette, Robert A. (2011)

    Journal article
    University of Waikato

    This review summarizes research concerning Antarctic fungi at the century-old historic huts of the Heroic Period of exploration in the Ross Dependency 1898–1917 and fungi in pristine terrestrial locations. The motivation of the research was initially to identify potential fungal causes of degradation of the historic huts and artifacts. The research was extended to study fungal presence at pristine sites for comparison purposes and to consider the role of fungi in the respective ecosystems. We employed classical microbiology for isolation of viable organisms, and culture independent DNA analyses. The research provided baseline data on microbial biodiversity. Principal findings were that there is significant overlap of the yeasts and filamentous fungi isolated from the historic sites, soil, and historic introduced materials (i.e., wood, foodstuffs) and isolated from environmental samples in pristine locations. Aerial spore monitoring confirmed that winter spore counts were high and, in some cases, similar to those found in summer. Microbial diversity varied between the three Ross Island historic sites, and one historic site showed noticeably higher diversity, which led to the conclusion that this is a variable that should not be generalized. Cultured fungi were cold active, and the broader scientific significance of this finding was that climate change (warming) may not adversely affect these fungal species unless they were out-competed by new arrivals or unfavorable changes in ecosystem domination occur.

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