Holm and Andersson

The hydrothermal systems, hundreds of meters under the surface of the ocean, would have protected evolving systems from the high-energy cosmic radiation as well as from meteorite impacts. Even partial evaporation of sea water, due to gigantic impacts, could have been resisted by molecular systems present at great depths (Holm and Andersson, 1995). 

Holm and Andersson have provided an up-to-date survey of simulation experiments on the synthesis under hydrothermal conditions of molecules important for biogenesis (Holm and Andersson, 2005). It is clear that several research groups have been able to show in the meantime, using simulation experiments, that the conditions present at deep sea vents appear suitable for the synthesis of very different groups of substances. However, it remains unclear how these compounds could have been stabilized and protected against rapid decomposition. At present, metal ions (as complexing agents) and mineral surfaces are the subject of discussion and experiment. 

Table 7.1 Comparison of the yields of carbon-containing compounds obtained from an atmosphere of CH4, NH3, H2O and H2 using spark discharges with those obtained under hydrothermal conditions from a mixture of HCN, HCHO and NH3 at 423 K and 10 atm in the presence of pyrite-pyrrhotite-magnetite redox buffer (Holm and Andersson, 1995)...

The question of the elimination of water in polycondensation reactions still provides an unsolved problem. Solutions are being searched for in many laboratories, for example in Italy Paly6 and Zucchi from the University of Modena consider it possible that limited regions where liquid or supercritical CO2 phases were present could have existed on the young Earth. Such regions, with non-aqueous media, could have been particularly favourable for some prebiotic reactions, such as those involving the elimination of water. Experiments to study this hypothesis are planned (Paly6 and Zucchi, 2002 Holm and Andersson, 1998). 

We also know that a considerable enrichment of prebiotic moieties may have come from submarine vents and other hydrothermal sources (see, for example, Miller and Bada, 1988 Holm and Andersson, 1998 Stetter, 1998). Let s start with the 1979 discovery of deep-sea vents with black smokers, which are associated with an extraordinary abundance of the most phylogenetically primitive organisms on Earth. This ecosystem is sulphur based, and is distinct from the more familiar, photosynthetically-based ecosystem that dominates Earth s surface. Corliss et al. (1981) were struck by the richness of the vent biota, based on chemosynthesis, and proposed that these were the origin of life. 

Holm NG (1992) Why are hydrothermal systems proposed as a plausible environment for the origin of life In Holm NG (Ed.) Marine Hydrothermal Systems and the Origin of Life. Kluwer, Dordrecht Boston London, p 5 Holm NG, Andersson EM (2005) Astrobiologie 5 444 Holm NG, Andersson EM (1995) Planet Space Sci 43 153... 

Holm, N. G. and Andersson, E. M. (1998). Hydrothermal systems. In The Molecular Origin of Life, ed. A. Brack. Cambridge University Press. 

Lindh JD, Holm L, Andersson ML, Rane A. Influence of CYP2C9 genotype on warfarin dose requirements—a systematic review and meta-analysis. Eur J Clin Pharmacol 2009 65(4) 365-75. 

Nyholm, S. H., Alexander, J., Lundanes, E., Frandsen, H., Andersson, R., Grivas, S., Nesnow, S., and Holme, J. A. (1996). Biotransformation of die cyclopenta-fused polycyclic aromatic hydrocarbon benz[/]aceanthrylene in isolated rat Uver cell Identification of nine new metabolites. Carcinogenesis 17, 1111-1120. 

Eriksson BKG, Andersson J, Holm SE, Norgren M Invasive group A streptococcal infections T1M1 isolates expressing pyrogenic exotoxins A and B in combination with selective lack of toxin-neutralizing antibodies are associated with increased risk of streptococcal toxic shock syndrome. J Infect Dis 1999 1X0 410 -IIS. 

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