Encyclopedia of Astrobiology

2011 Edition
| Editors: Muriel Gargaud, Ricardo Amils, José Cernicharo Quintanilla, Henderson James (Jim) CleavesII, William M. Irvine, Daniele L. Pinti, Michel Viso


  • Josefa AntónEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-3-642-11274-4_695



Compatible solutes, ionic stress, salt


Halotolerance is tolerance to ionic stress, or the ability of an organism to grow at salt concentrations higher than those required for growth. Halotolerant organisms are able to survive at high salt concentrations but do not require these conditions for growth.


Halotolerance is a relative term that refers to the ability to survive or thrive at salt concentrations higher than those necessary for growth. A microorganism is considered extremely halotolerant if its growth range extends above 2.5 M salt. A 0.9% NaCl would be considered an isotonic solution by most nonmarine and non-halophilic organisms. In nature, halotolerant organisms can be found in settings such as saline waters and soils that are inhabited by autochthonous  halophilic microbiota, or even in association with animals. Such is the case of microbiota such as Staphylococcusspecies that live on human skin. Because of their...

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References and Further Reading

  1. DasSarma S, Arora P (2006) Halophiles. Encyclopedia of life sciences. Wiley, LondonGoogle Scholar
  2. Oren A (2006) Life at high salt concentrations. In: Dworkin M (ed) The prokaryotes: a handbook on the biology of bacteria. Springer, New YorkGoogle Scholar
  3. Oren A (2008) Microbial salt at high salt concentrations: phylogenetic and metabolic diversity. Saline Systems 4:2CrossRefGoogle Scholar
  4. Roberts MF (2005) Organic compatible solutes of halotolerant and halophilic microorganisms. Saline Systems 1:5CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  1. 1.Departamento de Fisiología, Genética y MicrobiologíaUniversidad de AlicanteAlicanteSpain