Ciencia y Sociedad

Friday, May 09, 2008

Life Evolving in Ice...

It was only until a few weeks ago that the article by Douglass Fox "Did Life Evolve in Ice?" published in the magazine DISCOVER -february 2008- came into my hands. Stanley Miller -unfortunately deceased- once again suceeded in drawing the attention of the scientific world after his 1950´s fascinating experiments reproducing earth´s primeval condition of simple gases and synthesis of complex biomolecules under WARM and humid conditions. This time Discover presents how Miller was able to synthesize complex biomolecules from simple ones by FREEZING them together for several decades under subzero temperatures; other scientists in the field have followed Miller´s footprints obtaining additional supporting data as communicated in Fox´s article. Life´s early biomolecules do seem to have formed then, not only under earthly "primordial soup" environment but ALSO under low freezing conditions.

In this text we would like to remark how the idea of life "EVOLVEMENT" goes beyond the mere abiotic synthesis of biomolecules. It involves, to put it briefly, at least TWO concepts; one, the concept of complex biomolecule formation as a precondition to cell formation AND a second one: the concept of BIODIVERSITY as a precondition to EVOLUTION -mutation and selection- . The first concept is indeed approached with the new results by Miller and colleagues, but not the second one, that has to do more with the long history of structural associations between DNA, water molecular net sustaining it and their modifications. Since the early papers by Watson, Crick, Wilkins and Franklin ( see J. Herbert Taylor´s "Selected Papers in Molecular Genetics", ed. Acad. Press, NY-London, 1965 ) it became clear that the degree of hydration in the DNA molecule does affect it´s molecular structure in several ways. It is the water framework, surrounding grid or "squeleton" of the DNA double helix, the one that holds together the helices and not the the hydrogen bridges between them, myth that seems to endure...Furthermore,the elimination of water from BIOLOGICALLY ACTIVE DNA in the laboratory by freeze-drying techniques (lyophilization) does alter genotype and it´s phenotypic expression in several types of cells, see (p. 204, Genetics, in Wayne W.Umbreit´s "Modern Microbiology", ed. W.H. Freeman Co.,San Fco.-London,1962), ( Servin-Massieu, M. and R.Cruz Camarillo, "Variants of Serratia marcescens Induced by Freeze Drying" in Applied Microbiology, vol.18, p.689-691, 1969), (Servin-Massieu, M., "Effects of Freeze Drying and Sporulation on Microbial Variation" in Current Topics in Microbiology and Immunology, vol.54, p. 119-150, 1971, ed. Springer -Verlag, Berlin-Heidelberg-NY).

Present data allows us to say then, that not only life´s biomolecules do seem to form under subzero freezing conditions, but cell biodiversity and evolutionary processes also seem to manifest themselves under freeze-drying condition cycles in the laboratory and -presumably- under earthly and other celestial bodies conditions having cycles resembling freezing and drying.