Archaea halophilic species

Natural selection, one of the key forces powering evolution, opens an array of improbable ecological niches to species that can adapt biochemically. (Left) Salt pools, where the salt concentration can be greater than 1.5 M, would seem to be highly inhospitable environments for life. Yet certain halophilic archaea, such as Haloferax mediterranei (right), possess biochemical adaptations that enable them to thrive under these harsh conditions. [(Left) Kaj R. Svensson/ Science Photo Library/Photo Researchers (right) Wanner/Eye of Science/Photo Researchers.]... 

From the bioenergetic point of view, Halobacterium halobium has been studied much more extensively than other extremely halophilic archaea it is in this species that bacteriorhodopsin was first found. (Later it has also been observed in closely related species H. cutirubrum and H. salinarium [2].) In H. halobium, three types of energy-supplying processes have been identified, namely, (i) respiration, (ii) light-dependent ion pumping and (hi) arginine fermentation (Fig. 1). 

Variants of the diphytanylglyceroldiether (1) found in some archaea are as follows (a) both the C20-C25 diether (structure lA, Fig. 1) and C25-C25 diether (structure IB) core lipids occur in alkaliphilic species of extreme halophiles Natronobacterium and Natronococcus)[30, il, and the C20-C25 diether (lA) also occurs in Halococci[32 and in Halobacterium, Haloferax and Natronobacterium strains from hypersaline environments in India [33] (b) a macrocyclic C4o-diether (structure 1C, Fig. 1) [34] is... 

The production of PHA from the extremely halophilic Archaea has become the subject of recent research. Halophilic strains from the genera Haloarcula, Natrialba, Haloterrigena, Halococcus, Haloquadratum, Halorubrum, Natronobacterium, Natronococcus and Halobacterium have been reported as PHA accumulators [38]. Several halophilic Archaeal species, in the genera Haloferax and... 

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