Haloferax mediterranei
| Haloferax mediterranei | |
|---|---|
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SEM image of Haloferax mediterranei .
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Scientific classification 
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| Domain: | Archaea |
| Kingdom: | Euryarchaeota |
| Class: | Halobacteria
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| Order: | Haloferacales |
| Family: | Haloferacaceae |
| Genus: | Haloferax |
| Species: | H. mediterranei
|
| Binomial name | |
| Haloferax mediterranei (Rodriguez-Valera et al. 1983) Torreblanca et al. 1987[1]
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| Synonyms | |
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Haloferax mediterranei is a species of archaea in the family Haloferacaceae.[1]
Discovery
Haloferax mediterranei was discovered in 1983 in marine salterns in the village of Santa Pola, Spain.[2] The species was initially named Halobacterium mediterranei, then renamed Haloferax mediterranei in 1986.[3] Haloferax mediterranei is the fastest-growing known member of the Halobacteriales under optimal laboratory conditions, but it is relatively rare in the environment.[4] The full genome of H. mediterranei was sequenced in 2012.[5]
Metabolism and Growth Conditions
Haloferax mediterranei is the fastest-growing archaeon in the Halobacteriales family,[4] with generation times as low as 1.2 hours reported under optimal laboratory growth conditions.[6] Haloferax mediterranei is able to use a variety of compounds as carbon and energy sources,[7] and can accumulate materials to serve as a source of carbon and energy, as well as use organic and inorganic nitrogen sources.[4] H. mediterranei is an extremely versatile microorganism that can anaerobically or aerobically, tolerate a wide range of salinities (between 10% and 32.5%), a wide range of pH values (between 5.75 and 8.75) and a wide range of temperatures (between 18 and 55oC).[7][6][4] It can also tolerate a variety of high metal concentrations, such as nickel, lithium, cobalt and arsenic, which are toxic to most organisms.[6]
Morphology and Cell Division
Haloferax mediterranei is an extremely pleomorphic organism, cells are usually flat disks.[4] Like Haloferax volcanii, it performs cell division through the formation of an FtsZ ring.[8]
Biofilm and Exopolysaccharide formation
Haloferax mediterranei produces a mucous exopolysaccharide matrix that accumulates as a top layer in liquid medium.
PHA and PHB synthesis
H. mediterranei, when grown under phosphate limitation,[12] produces polyhydroxyalkanoates, a type of biodegradable thermoplastic currently commercially produced using bacteria.[13] It has been suggested that H. mediterranei is a good candidate for industrial production of biodegradable thermoplastics due to its fast growth, low contamination rates and ease of lysis.[14] Deleting the genes responsible for exopolysaccharide synthesis results in a 20% increase in the amount of PHAs in the cell.[13] Increasing the salt concentration of the media also increased the concentration of PHAs produced.[15]
Gas Vesicles
Like some other members of the Halobacteriales group, notably Halobacterium salinarum, Haloferax mediterranei produces gas vesicles, believed to act aiding buoyancy. The production of gas vesicles only occurs in high salt concentrations and once cells have reached stationary phase.[4] By transforming 14 genes from the vac cluster of H. mediterranei into a gas-vesicle deficient archaeon H. volcanii, researchers found that H. volcanii is able to produce functional gas vacuoles.[16][17]
References
- ^ Deutsche Sammlung von Mikroorganismen und Zellkulturen. Retrieved 2022-07-15.
- S2CID 42827598.
- ISSN 0723-2020.
- ^ S2CID 5047263.
- PMID 22843593.
- ^ PMID 33567751.
- ^ ISBN 978-1-118-96060-8.
- PMID 10721730.
- ^ PMID 16347749.
- PMID 22007151.
- PMID 33328348.
- ISBN 978-1-4613-6660-7.
- ^ S2CID 253771071.
- PMID 22776040.
- S2CID 90828798.
- PMID 9611808.
- S2CID 19696507.
External links
- Oren, Aharon; Hallsworth, John E. (2014-08-28). "Microbial weeds in hypersaline habitats: the enigma of the weed-like Haloferax mediterranei". FEMS Microbiology Letters. 359 (2). Oxford University Press (OUP): 134–142. S2CID 5047263.