title: Proteome of tolerance fine-tuning in the human pathogen black yeast Exophiala dermatitidis.
abstract: The black yeast Exophiala dermatitidis is a worldwide distributed agent of primary and secondary diseases in both immunocompromised and healthy humans, with a high prevalence in human-made environments. Since thermo-tolerance has a crucial role in the fungus persistence in man-dominated habitat and in its pathogenicity, three incubation temperatures (37, 45, 1 °C) and two time spans (1 h, 1 week) were selected to simulate different environmental conditions and to investigate the effect of temperature on the proteome of E. dermatitidis CBS 525.76. Using a novel protocol for protein extraction from black yeasts, 2-D DIGE could be applied for characterization of changes in total protein spot abundance among the experimental conditions. A total of 32 variable proteins were identified by mass spectrometry. Data about protein functions, localization and pathways were also obtained. A typical stress response under non-optimal temperature could not be observed at the proteome level, whereas a reduction of the metabolic activity, mostly concerning processes as the general carbon metabolism, was detected after exposure to cold. These results suggest that a fine protein modulation takes place following temperature treatment and a repertoire of stable protein might be at the base of E. dermatitidis adaptation to altered growth conditions.
  
  
  CONCLUSIONS
  E. dermatitidis is a pathogenic black yeast causing neurotropic infections, systemic and subcutaneous disease in a wide range of hosts, including humans. The discovery of the fungus high prevalence in man-made habitats, including sauna facilities, drinking water and dishwashers, generated concern and raised questions about the infection route. In the present work - which is the first contribution on E. dermatitidis proteome - the effect of different temperature conditions on the fungus protein pattern have been analyzed by using a gel-based approach and the temperature responsive proteins have been identified. The absence of a typical stress response following the exposure to non-optimal temperature was detected at the proteome level, along with a general reduction of the metabolic activity after exposure to cold. These results suggest that a very fine regulation of the protein expression as well as adaptations involving a basic set of stable proteins may be at the base of E. dermatitidis enormous ecological plasticity, which plays a role in the fungus distribution, also enabling the transition from natural to human habitat and to the human host.
authors.affiliation: VIBT Extremophile Center, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria. Electronic address: donatella.tesei@boku.ac.at.
authors.forename: Donatella
authors.initials: D
authors.lastname: Tesei
authors.affiliation: Plant Biotechnology Unit, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria.
authors.forename: Gorji
authors.initials: G
authors.lastname: Marzban
authors.affiliation: Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-IAC, 1060 Vienna, Austria.
authors.forename: Martina
authors.initials: M
authors.lastname: Marchetti-Deschmann
authors.affiliation: VIBT Extremophile Center, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria.
authors.forename: Hakim
authors.initials: H
authors.lastname: Tafer
authors.affiliation: Institute for Applied Genetics and Cell Biology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria.
authors.forename: Elsa
authors.initials: E
authors.lastname: Arcalis
authors.affiliation: VIBT Extremophile Center, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria.
authors.forename: Katja
authors.initials: K
authors.lastname: Sterflinger
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D001426:Bacterial Proteins / Q000378:metabolism*; D005093:Exophiala / Q000166:cytology* / Q000502:physiology*; D018869:Heat-Shock Response / Q000502:physiology*; D006801:Humans; D020543:Proteome / Q000378:metabolism*; D013312:Stress, Physiological / Q000502:physiology*; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D020543:Proteome
keywords: DIGE; Fungal proteomics; Pathogenic fungi; Thermo-tolerance; nLC-ESI-MS/MS