Halomonadaceae is a family of

halophilic The halophiles, named after the Greek word for "salt-loving", are extremophiles that thrive in high salt concentrations. While most halophiles are classified into the domain Archaea, there are also bacterial halophiles and some eukaryotic species, ...

Pseudomonadota.

History

The family was originally described in 1988 to contain the genera ''Halomonas'' and ''Deleya''. In 1989, ''Chromobacterium marismortui'' was reclassified as ''Chromohalobacter marismortui'' forming a third genus in the family Halomonadaceae. Subsequently, in 1990 a species was discovered and was originally proposed to be called ''Volcaniella eurihalina'' forming a new genus in the ''Halomonadaceae'', but was later (in 1995) reclassified as a member of the genus ''Halomonas''. 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, but it has been proposed to reclassify it into the family. 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. 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. and now comprising two species (the other being Halovibrio denitrificans) In 2002, ''Halomonas marina'' was transferred to its own genus ''Cobetia'', 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, ''Aidingimonas halophila'' in 2009, ''Halospina denitrificans'' in 2006, ''Modicisalibacter tunisiensis'' in 2009 ''Salinicola socius'' in 2009. To the latter genus two species were transferred ''Halomonas salaria'' as '' Salinicola salarius'' and ''Chromohalobacter salarius'' as '' Salinicola halophilus''. The family also contain the recently discovered but uncultured bacterium "

Candidatus In prokaryote nomenclature, ''Candidatus'' (Latin for candidate of Roman office) is used to name prokaryotic phyla that are well characterized but yet-uncultured. Contemporary sequencing approaches, such as 16S sequencing or metagenomics, provide m ...

Portiera aleyrodidarum" (primary endosymbionts of

whiteflies Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described. Description and taxonomy The ...

Genera

* ''Halomonas'', the type genus ** ''Halomonas elongata'', the type species of the genus, however the longest known members of the family are ''Halomonas halodentrificans'' (1952), ''Chromohalobacter marismortui'' (1940) and ''Chromohalobacter beijerinckii'' (originally ''Pseudomonas beijerinckii''). ** ''Halomonas titanicae'' * ''Aidingimonas halophila'' * ''Cobetia'' ** '' Cobetia marina'', originally ''Pseudomonas marina'', then ''Dalya marina'', then ''Halomonas marina''. ** '' Cobetia crustatorum'', isolated from fermented Korean seafood * ''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'' * ''Kushneria'' ** ''Kushneria aurantia'', type species ** ''Kushneria marisflavi'', ''Kushneria indalinina'' and ''Kushneria avicenniae'' were previously classified under ''Halomonas'' * ''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 The International Code of Nomenclature of Prokaryotes (ICNP) formerly the International Code of Nomenclature of Bacteria (ICNB) or Bacteriological Code (BC) governs the scientific names for Bacteria and Archaea.P. H. A. Sneath, 2003. A short histor ...

made in as noted in Note: Species of ''Deleya'' and ''Halovibrio'' are 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

Research

Geomicrobiologist Geomicrobiology is the scientific field at the intersection of geology and microbiology and is a major subfield of geobiology. It concerns the role of microbes on geological and geochemical processes and effects of minerals and metals to microb ...

Felisa Wolfe-Simon with a NASA funded team is researching a particular strain the family Halomonadaceae, named

GFAJ-1 GFAJ-1 is a strain of rod-shaped bacteria in the family Halomonadaceae. It is an extremophile that was isolated from the hypersaline and alkaline Mono Lake in eastern California by geobiologist Felisa Wolfe-Simon, a NASA research fellow in resi ...

, isolated and cultured from sediments collected along the shore of

Mono Lake Mono Lake ( ) is a saline soda lake in Mono County, California, formed at least 760,000 years ago as a terminal lake in an endorheic basin. The lack of an outlet causes high levels of salts to accumulate in the lake which make its water a ...

, near Yosemite National Park in eastern

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

. This GFAJ-1 strain of Halomonadaceae can grow in the presence of high concentrations of

arsenic Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, ...

References

External links