What the Hell? In Hades, they have their own unique microflora.What Hell holds for these organisms is largely unknown, except that they actually use carbon monoxide for energy. We have only just started looking at deep-sea and deep-in-the-ground life. These Hadesarchaea were first discovered in the US by Carl Woese, but now appear to be of even more immense significance. Useful? You bet! Andreas Teske and Ketil B SÃ ¸rensen of the Universities of North Carolina (US) and the National University of Ireland provide the research into probably one of the most promising areas of original research for many years.

Despite never being studied to any degree compared to their more complex relatives, the bacteria, they are very diverse, rather like the animal and plant kingdoms combined! The MBG-B (Marine benthic Group of Hadesarchaea) are a deep sea group, dominant in the phylogeny, but compete with the MHVG (Marine Hydrothermal Vent Group and others found more recently. Terrestrial groups, often discovered in African gold mines are sometimes related to the other marine groups.

We have now investigated every organisms secret closet, the genome. Living without oxygen and using CO (carbon monoxide) as an energy source, Hadesarchaea obviously possess unknown qualities. Extreme conditions demand extreme physiological adaptation, but it is possible there are useful abilities within these genomes. The goldmine SAGMEG (South African Goldmine Euryarcheotal Group) are metabolically active in deep sea environments as well as terrestrial ones. On the other hand, the TMEG (Terrestrial Miscellaneous Euryarcheotal Group) has marine members but is still named as an earthly group. All of this points to gaps in the knowledge, with many more groups living down there in the earth or the sea, beyond our present scope for discovery.

We are talking about the biggest habitat for microorganisms that is available. It is a whole biosphere. The global carbon cycle could be highly indebted to these ancient life forms, although we don't know by how much. NASA have a try at exploring the carbon commitments of archaea in our story here. Have a look at the scientists' highly original paper named Uncultured archaea in deep marine subsurface sediments: have we caught them all? in the Nature journal ISME.