Halobacterium salinarum

Taxobox
color = darkgray
name = "Halobacterium salinarum"
domain = Archaea
phylum = Euryarchaeota
classis = Halobacteria
ordo = Halobacteriales
familia = Halobacteriaceae
genus = Halobacterium
binomial = "Halobacterium salinarum"
binomial_authority = corrig. (Harrison and Kennedy 1922)
Elazari-Volcani 1957
synonyms = "Pseudomonas salinaria" Harrison and Kennedy 1922
"Serratia salinaria" (Harrison and Kennedy 1922) Bergey "et al". 1923
"Flavobacterium" (subgen. "Halobacterium") "salinarium" (Harrison and Kennedy 1922) Elazari-volcani 1940
"Halobacter salinaria" (Harrison and Kennedy 1922) Anderson 1954
"Halobacterium salinarium" (Harrison and Kennedy 1922) Elazari-Volcani 1957
"Halobacterium halobium" (Petter 1931) Elazari-Volcani 1957
"Halobacterium cutirubrum" (Lochhead 1934) Elazari-Volcani 1957

"Halobacterium" is an extremely halophilic marine gram-negative obligate aerobic archaeon. Despite its name, this microorganisms is not a bacterium, but rather a member of the Domain Archaea. It is found in salted fish, hides, hypersaline lakes, and salterns. Salterns are enclosed basins filled with seawater that are left to evaporate, yielding solar sea salt. As these salterns reach the minimum salinity limits for extreme halophiles, their waters become purple or reddish color due to the algal bloom of halophilic Archaea. "H. salinarum" has also been found in high-salt food such as salt pork, marine fish, and sausages.

To survive in extremely salty environments, this archaeon -- as with other halophilic Archaean species -- utilizes compatible solutes (in particular potassium chloride) that acts as a sort of antifreeze/coolant to keep the cell metabolism functioning.

"H. salinarum" is an obligate aerobe. It reproduces by binary fission. It does not form spores. Most are not motile.

Halobacterium salinarum is responsible for the bright pink or red appearance of the Dead Sea and other bodies of salt water Halobacteria are single-celled, rod-shaped microorganisms that are among the most ancient forms of life and appeared on earth billions of years ago. Halobacteria are archaea that grow optimally in extremely high saline environments (up to 5.5 M NaCl). Their natural habitats are salt evaporation ponds and natural salt lakes and other environments where the salt concentration comes close to saturation. Occasionally they are isolated from hides and from the surfaces of heavily salted foods.

Halobacterium sp. NRC-1 is as easy to culture as E. coli and serves as an excellent model system for archaeal genetics and functional genomics.

Whole proteome comparisons show the definite archaeal nature of this halophile with additional similarities to the Gram-positive Bacillus subtilis and other bacteria.

Whole genome sequences are available for two strains of "H. salinarum", [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=64091&lvl=3&lin=f&keep=1&srchmode=1&unlock NRC-1] and [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=478009&lvl=3&lin=f&keep=1&srchmode=1&unlock R1]

References

[http://www.ncbi.nlm.nih.gov/pubmed/11016950 Genome sequence of Halobacterium species NRC-1.] Ng, et. al.Proc Natl Acad Sci U S A. 2000 Oct 24;97(22):12176-81.