Physiological characteristics of fungi associated with antarctic environments

dc.contributor.advisorChairperson, Graduate Committee: John C. Priscuen
dc.contributor.authorKudalkar, Priyanka Sushilen
dc.coverage.spatialMcMurdo Dry Valleys (Antarctica)en
dc.date.accessioned2016-10-27T15:49:51Z
dc.date.available2016-10-27T15:49:51Z
dc.date.issued2016en
dc.description.abstractThe permanent ice covers on the lakes of Antarctica's McMurdo Dry Valleys region harbor a diverse group of phototrophic and heterotrophic microorganisms that metabolize during the short summer months when solar radiation produces melt inclusions within the ice and provides energy to drive photosynthesis. Laboratory cultures of fungi were obtained from ice cores taken from Lakes Bonney (east lobe) and Chad, and sediments collected from Subglacial Lake Whillans (West Antarctica). Using molecular techniques, the internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA) was sequenced to identify fungal types and to determine whether they may be unique to this region. Four axenic fungal cultures, Tetracladium ellipsoideum, Lecythophora hoffmannii, Mucor sp., and an unidentified Ascomycota were successfully isolated. These isolates are closely related to organisms that have been previously reported in Antarctica and other cold habitats. The isolates were tested for growth characteristics under various temperature and nutrient regimes. Temperature response experiments revealed that all the isolated fungi were psychrotolerant and growth rates were greatest at 25°C. Of major significance in evaluating the potential of Antarctic fungi as a bioresource is their ability to produce bioactive compounds. Two out of four isolated organisms exhibited antimicrobial activity against several plant pathogens. The metabolic potential and preferred substrate utilization was examined by exposing fungal isolates to a variety of substrates in a 96 well "Biolog" plate. A strong correlation was found among substrate utilization, isolates, temperature and the different carbon substrates. This experiment revealed that the isolated fungi have preferences for different labile carbon substrates at 4°C and 24°C which may imply different physiologies at different times of year in the lake ice-covers. Results from my studies will help understand the role of fungi in lake ice and subglacial lake sediment ecosystems, and the physiology of fungi living in cold environments.en
dc.identifier.urihttps://scholarworks.montana.edu/handle/1/9835en
dc.language.isoenen
dc.publisherMontana State University - Bozeman, College of Agricultureen
dc.rights.holderCopyright 2016 by Priyanka Sushil Kudalkaren
dc.subject.lcshFungien
dc.subject.lcshBioactive compoundsen
dc.titlePhysiological characteristics of fungi associated with antarctic environmentsen
dc.typeThesisen
mus.data.thumbpage36en
mus.relation.departmentLand Resources & Environmental Sciences.en_US
thesis.catalog.ckey3149317en
thesis.degree.committeemembersMembers, Graduate Committee: Cathy L. Cripps; Gary Strobel.en
thesis.degree.departmentLand Resources & Environmental Sciences.en
thesis.degree.genreThesisen
thesis.degree.nameMSen
thesis.format.extentfirstpage1en
thesis.format.extentlastpage81en

Files

Original bundle

Now showing 1 - 1 of 1
Thumbnail Image
Name:
KudalkarP0516.pdf
Size:
1 MB
Format:
Adobe Portable Document Format
Copyright (c) 2002-2022, LYRASIS. All rights reserved.