In the harshest environments of our planet, in places like volcanoes, we imagine an extremely hot and toxic place, unlikely to harbor any life. In salt deserts the image is the same. However, this first impression can be misleading, these environments have been showing to be filled with life, populated by organisms that are denominated extremophiles.
Extremophiles are very peculiar organisms in many aspects. The harsh environments they live are diverse: we can find extremophiles in sulfuric acid (acidophiles), living underneath thick ice (psycrophiles) and some that live under a high salt concentration (halophiles), among other examples. Another interesting aspect of these organisms is how they have adapted their metabolism and physiology to survive and thrive in these environments. Extremophiles, for their ability to survive in extreme conditions, are great candidates for the studies of origin and evolution of life in the Astrobiology field, also providing new hypotheses on the habitability of exoplanets.
The majority of extremophiles can be classified in two of the three domains of life, Bacteria and Archaea, both being represented by procaryotic organisms, the Eukaryota domain comprehends fewer extremophiles. A classic examples of extremophile in Bacteria is Thermus aquaticus, which can survive at high temperatures and was an important participant in the evolution of Molecular Biology, providing a DNA polymerase able to handle higher temperatures used in PCR techniques. Deinococcus radiodurans which is extremely resistant against radiation, vacuum, cold and acids is called a poliextremophile.
In our laboratory, we have as a model organism the halophilic Archaea Halobacterium salinarum - NRC 1. The Systems Biology approach used, focusing ncRNAs,might provide us new clues about evolution and physiology of this organism thus providing data for the advance of Synthetic Biology.