noun, plural: halophiles
A halophile is an organism that lives in an environment that has a high salinity such as ocean and solid salt crystals. Halophiles are found thriving in habitats with a high concentration of salt, such as in the Great Salt Lake in Utah and Owens Lake in California. Organisms that live in oceans may be regarded as slightly halophilic. However, there are organisms that prefer environment that has an extremely high salt content. These organisms are referred to as extreme halophiles or hyperhalophiles. Extreme halophiles prefer 20 to 30% salt content.1 These halophiles are a type of extremophiles. Halophiles are able to live in saline environment because they can accumulate internal organic compatible solutes that can balance the osmotic stress of their environment. Others are capable of producing acidic proteins that increase solvation and thereby improve function in high salinity.2
Many of the hyperhalophiles belong to the domain Archaea. An example of archaea that is halophilic is that which belongs to the group Haloarchaea. Many of them prefer an environment that is saturated with salt. Apart from archaea, there are also bacterial species that are hyperhalophilic. An example is Salinibacter ruber. It is a red bacterium found in saltern crystallizer ponds in Alicante and Mallorca, Spain. It optimally grows in an environment with a salinity ranging from 20 to 30%. It cannot live in an environment below 15% salt concentration.
Word origin: halo- (salt) + phile (love)
- extreme halophile
1 Ollivier, B., Caumette, P., Garcia, J-L. and Mah, R. (1994) Anaerobic bacteria from hypersaline environments. Microbiological Reviews 58(1):27-38.
2 DasSarma, S., and DasSarma, P. (Mar 2012) Halophiles. In: eLS. John Wiley & Sons Ltd, Chichester. Retrieved from [].