Halobacteria 244142 221780243 2008-06-26T01:59:29Z Isolation booth 7263958 {{Taxobox | color = #F3E0E0 | name = Halobacteria | image = Halobacteria.jpg | image_width = 200px | image_caption = ''[[Halobacterium]]'' sp. strain NRC-1, each cell about 5 µm in length. | domain = [[Archaea]] | phylum = [[Euryarchaeota]] | classis = [[Halobacteria]] | subdivision_ranks = [[Order (biology)|Order]] | subdivision = * [[Halobacteriales]] | synonyms = * Halobacteria Grant et al. 2002 <br /> }} : '' '''Note:''' The word "halobacteria" is also the plural form of the word "[[halobacterium]]".'' Halobacteria are more correctly called [[Haloarchaea]], but halobacteria remains in common usage as they were originally designated as such before the existence of the domain [[Archaea]] was realised. In [[alpha taxonomy|taxonomy]], the '''Halobacteria''' (also '''Halomebacteria''') are a [[class (biology)|class]] of the [[Euryarchaeota]],<ref>See the [[National Center for Biotechnology Information|NCBI]] [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=183963 webpage on Halobacteria]. Data extracted from the {{cite web | url=ftp://ftp.ncbi.nih.gov/pub/taxonomy/ | title=NCBI taxonomy resources | publisher=[[National Center for Biotechnology Information]] | accessdate=2007-03-19}}</ref> found in [[water]] saturated or nearly saturated with [[salt]]. They are also called [[halophile]]s, 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. Halobacteria can grow [[Cellular respiration#Aerobic_respiration|aerobically]], anaerobically, or by means of [[photosynthesis]]. Parts of the [[Biological membrane|membrane]]s of halobacteria are purplish in color, and large blooms of Halobacteria appear reddish, from the pigment [[bacteriorhodopsin]], related to the [[Retina|retinal]] pigment [[rhodopsin]]. This pigment is used to absorb light, which provides energy to create [[Adenosine triphosphate|ATP]]. Halobacteria also possess a second pigment, [[halorhodopsin]], which pumps chloride ions in the cell in response to photons, creating a voltage gradient and assisting in the production of energy from light. The process is unrelated to other forms of [[photosynthesis]] involving electron transport however, and halobacteria are incapable of [[carbon fixation|fixing carbon]] from [[carbon dioxide]]. ==References== {{reflist|1}} ==Further reading== ===Scientific journals=== * {{ cite journal | last = Cavalier-Smith | first = T | date = 2002 | title = The neomuran origin of archaebacteria, the negibacterial root of the universal tree and bacterial megaclassification | journal = Int. J. Syst. Evol. Microbiol. | volume = 52 | pages = 7&ndash;76 | pmid = 11837318}} * {{ cite journal | last = Woese | first = CR | coauthors = Kandler O, Wheelis ML | date = 1990 | title = Towards a natural system of organisms: proposal for the domains Archaea, Bacteria, and Eucarya | journal = Proc. Natl. Acad. Sci. USA | volume = 87 | pages = 4576&ndash;4579 | pmid = 2112744 | doi = 10.1073/pnas.87.12.4576}} * {{ cite journal | last = Cavalier-Smith | first = T | date = 1986 | title = The kingdoms of organisms | journal = Nature | volume = 324 | pages = 416&ndash;417 | pmid = 2431320 | doi = 10.1038/324416a0}} ===Scientific books=== * {{ cite book | author = Grant WD, Kamekura M, McGenity TJ, Ventosa A | date = 2001 | chapter = Class III. Halobacteria class. nov. | title = Bergey's Manual of Systematic Bacteriology Volume 1: The Archaea and the deeply branching and phototrophic Bacteria | edition = 2nd ed. | editor = DR Boone and RW Castenholz, eds. | pages = p. 169 | publisher = Springer Verlag | location = New York | isbn = 978-0387987712 }} * {{ cite book | author = Garrity GM, Holt JG | date = 2001 | chapter = Phylum AII. Euryarchaeota phy. nov. | title = Bergey's Manual of Systematic Bacteriology Volume 1: The Archaea and the deeply branching and phototrophic Bacteria | edition = 2nd ed. | editor = DR Boone and RW Castenholz, eds. | pages = p. 169 | publisher = Springer Verlag | location = New York | isbn = 978-0387987712 }} ===Scientific databases=== {{Taxonomic references|taxon=Halobacteria}} ==External links== {{Taxonomic links|microbe=yes|NCBI_taxID=183963|taxoname=Halobacteria|LSPN_letter=h|LSPN_taxoname=halobacteria}} {{archaea-stub}} [[Category:Archaea taxonomic classes]] [[Category:Extremophiles]] [[Category:Phototrophic bacteria]] [[Category:Microbiology]] [[ca:Halobacteri]] [[de:Halobakterien]] [[es:Halobacteria]] [[fr:Halobacteria]] [[nl:Halobacterie]] [[ja:高度好塩菌]] [[ru:Галобактерии]]