Extremely halophilic archaea and the issue of long-term microbial survival

  • Sergiu Fendrihan
  • Andrea Legat
  • Marion Pfaffenhuemer
  • Claudia Gruber
  • Gerhard Weidler
  • Friedrich Gerbl
  • Helga Stan-Lotter
Review Paper

Abstract

Halophilic archaebacteria (haloarchaea) thrive in environments with salt concentrations approaching saturation, such as natural brines, the Dead Sea, alkaline salt lakes and marine solar salterns; they have also been isolated from rock salt of great geological age (195–250 million years). An overview of their taxonomy, including novel isolates from rock salt, is presented here; in addition, some of their unique characteristics and physiological adaptations to environments of low water activity are reviewed. The issue of extreme long-term microbial survival is considered and its implications for the search for extraterrestrial life. The development of detection methods for subterranean haloarchaea, which might also be applicable to samples from future missions to space, is presented.

Keywords

Extreme halophiles Haloarchaea Life detection Microbial longevity Salt mines Salt sediments Space missions Subterranean Taxonomy of halobacteriaceae 

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Copyright information

© Springer Science+Business Media B.V. 2006

Authors and Affiliations

  • Sergiu Fendrihan
    • 1
  • Andrea Legat
    • 1
  • Marion Pfaffenhuemer
    • 1
  • Claudia Gruber
    • 1
  • Gerhard Weidler
    • 1
  • Friedrich Gerbl
    • 1
  • Helga Stan-Lotter
    • 1
  1. 1.Department of MicrobiologyUniversity of SalzburgSalzburgAustria

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