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Gewählte Doctoral Thesis:

Kristina Zakharova (2014): SURVIVAL STRATEGIES OF ROCK INHABITING FUNGI IN EXTREME ENVIRONMENTS.
Doctoral Thesis - Institut für Angewandte Mikrobiologie (IAM), BOKU-Universität für Bodenkultur, pp 110. UB BOKU obvsg FullText

Data Source: ZID Abstracts
Abstract:
Black microcolonial fungi (MCF) and black yeasts are among the most stress resistant eukaryotic organisms on Earths. In this work we tried to understand cellular mechanisms underlying the resistance of MCF against extreme environments. We selected three organisms representing different environments: two species of microcolonial – Cryomyces antarcticus from cold deserts, Knufia perforans from hot environments and a species of black yeasts – Exophiala jeanselmei which is closely related to human pathogen species of the genus. We investigated the survival strategies under poikilohydric conditions. To this aim selected strains of MCF were subjected to desiccation and re-hydration in climate chambers and subsequently RNA, sugar content and the protein pattern (using 2D-gel electrophoresis) were analyzed. In another study the organisms were exposed to thermo-physical Mars-like conditions in the simulation chamber of the German Aerospace Center (Berlin). The alterations at the protein expression level from various fungi species under Mars-like conditions were analyzed for the first time using 2D-gel electrophoresis (2DE). The comparative analysis of the protein patterns shows that the fungi not only survive exposure to Mars-like conditions: after one week of exposure they acclimatize and seem to be metabolically active. In order to get a better understanding about the cellular processes behind the stress resistance, C. antarcticus was selected as model organism for protein identification. To explore the protein repertoire of this fungus 2DE and MALDI-TOF/TOF mass spectrometry were performed. Only a limited number of proteins could be identified by using sequence homologies in public databases. Due to the rather low identification rate by sequence homology, this study reveals that a major part of the proteome of C. antarcticus varies significantly from other fungal species.

Betreuer: Sterflinger-Gleixner Katja
1. Berater: Lopandic Ksenija
2. Berater: Marzban Gorji

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