Halomonadaceae

Halomonadaceae
GFAJ-1 grown on phosphorus.
Scientific classification
Kingdom:	Bacteria
Phylum:	Proteobacteria
Class:	Gammaproteobacteria
Order:	Oceanospirillales
Family:	Halomonadaceae
Genera
Carnimonas Chromohalobacter Cobetia Halomonas Portiera Zymobacter

The Halomonadaceae are a family of halophilic Proteobacteria.

History

The family was originally described in 1988 to contain the genera Halomonas and Deleya.^[1]

In 1989, Chromobacterium marismortui was reclassified as Chromohalobacter marismortui forming a third genus in the family Halomonadaceae.^[2]

Subsequently, in 1990 a species was discovered and was originally proposed to be called Volcaniella eurihalina forming a new genus in the Halomonadaceae,^[3] but was later (in 1995) reclassified as a member of the genus Halomonas.^[4]

The species Carnimonas nigrificans (sole member of genus) was not placed in the family due to the lack of two out of 15 descriptive 16S rRNA signature sequences,^[5] but it has been proposed to reclassify it into the family.^[6]

In 1996, the family was later reorganised by unifying genera Deleya, Halomonas and Halovibrio and the species Paracoccus halodenitrificans into Halomonas and placing Zymobacter in this family.^[7] However, it was later discovered that the strain of Halovibrio variabilis DSM 3051 and DSM 3050 differed and the latter was made type strain of the Halovibrio, which remains still in use.^[8][9] and now comprising two species (the other being Halovibrio denitrificans)^[9]

In 2002, Halomonas marina was transferred to its own genus Cobetia,^[10] and in 2009 Halomonas marisflavi, Halomonas indalinina. and Halomonas avicenniae were transferred to a new genus called Kushneria (5 species)

Several singleton genera were created recently: in 2007, Halotalea alkalilenta was described,^[11] Aidingimonas halophila in 2009,^[12] Halospina denitrificans in 2006,^[9] Modicisalibacter tunisiensis in 2009^[13] Salinicola socius in 2009.^[14] To the latter genus two species were transferred Halomonas salaria as Salinicola salarius and Chromohalobacter salarius as Salinicola halophilus.^[15]

The family also contain the recently discovered but uncultured bacterium "Candidatus Portiera aleyrodidarum" (primary endosymbionts of whiteflies^[16]).

Genera

• Halomonas, the type genus
  • Halomonas elongata, the type species of the genus,^[17] however the longest known members of the family are Halomonas halodentrificans (1952),^[18] Chromohalobacter marismortui (1940)^[19] and Chromohalobacter beijerinckii (originally Pseudomonas beijerinckii).^[20]
• Aidingimonas halophila ^[21]
• Cobetia
  • Cobetia marina, originally Pseudomonas marina,^[22] then Dalya marina, then Halomonas marina.
  • Cobetia crustatorum, isolated from fermented Korean seafood^[23]
• Carnimonas
• Chromohalobacter
  • Chromohalobacter marismortui
  • Chromohalobacter beijerinckii
  • Chromohalobacter canadensis and Chromohalobacter israelensis, formerly of the genus Halomonas
  • Chromohalobacter japonicus
  • Chromohalobacter nigrandesensis
  • Chromohalobacter salarius
  • Chromohalobacter salexigens
  • Chromohalobacter sarecensis, phychrotolerant
• Halotalea alkalilenta^[24]
• Kushneria
  • Kushneria aurantia, type species
  • Kushneria marisflavi, Kushneria indalinina and Kushneria avicenniae were previously classified under Halomonas^[25]
• Modicisalibacter
• Portiera
• Zymobacter, not to be confused with Zymomonas mobilis, an alphaproteobacterion studies for its biofuel production, an easy error that even the International Code of Nomenclature of Bacteria made in ^[26] as noted in ^[27]

Note: Species of Deleya and Halovibrio are now now Halomonas

Etymology

The names derives from Halomonas, which is the type genus of the family, plus the suffix -aceae, ending to denote a family^[28]

Research

Geomicrobiologist Felisa Wolfe-Simon with a NASA funded team is researching a particular strain the Halomonadaceae family, named GFAJ-1, isolated and cultured from sediments collected along the shore of Mono Lake, near Yosemite National Park in eastern California.^[29][30] This GFAJ-1 strain of Halomonadaceae can grow in the presence of high concentrations of arsenic.^[31]

See also

• Geomicrobiology

References

External links

• NASA - Astrobiology Magazine: "Searching for Alien Life, on Earth" — (October 2009)
• NASA.gov: "NASA-Funded Research Discovers Life Built With Toxic Chemical" — (December 2010)
• Science Express abstract of F. Wolfe-Simon, et al.: "A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus." - (December 2010)