Halobacteria

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iHalobacteria

Scientific classification

Kingdom:	Archaea
Phylum:	Euryarchaeota
Class:	Halobacteria
Order:	Halobacteriales Grant & Larsen, 1989
Family:	Halobacteriaceae Gibbons, 1974

Genera

Haloalkalicoccus
Haloarcula
Halobacterium
Halobaculum
Halobiforma
Halococcus
Haloferax
Halogeometricum
Halorhabdus
Halorubrum
Halosimplex
Haloterrigena
Natrialba
Natrinema
Natronobacterium
Natronococcus
Natronomonas
Natronorubrum

Note: The word "halobacteria" is also the plural form of the word "halobacterium".

The halobacteria (also halomebacteria) are a class of archaea, found in water saturated or nearly saturated with salt. They are also called halophiles, though this name is also used for other organisms which live in somewhat less concentrated salt water. They are common in most environments where large amounts of salt, moisture, and organic material are available. Large blooms appear reddish, from the pigment bacteriorhodopsin. This pigment is used to absorb light, which provides energy to create ATP. The process is unrelated to other forms of photosynthesis involving electron transport; however, and halobacteria are incapable of fixing carbon from carbon dioxide.

Halobacteria can exist in salty environments because although they are aerobes they have a separate and different way of creating energy through photosynthesis. Parts of the membranes of halobacteria are purplish in color. These parts conduct photosynthetic reactions with retinal pigment rather than chlorophyll. This allows them to create a proton gradient across the membrane of the cell which can be used to create ATP for their own use.