Download GEOMICROBIOLOGY OF URANIUM DEPOSITS - SURVIVAL

GEOMICROBIOLOGY OF URANIUM DEPOSITS - SURVIVAL UNDER
RADIATION STRESS
Wolfgang E. Krumbein and Anna A. Gorbushina
Geomicrobiology, ICBM, Carl von Ossietzky Universitaet, Oldenburg (Germany) and
BIOGEMA (Edewecht, Germany) E-Mail: [email protected]
Natural reactors are known for several places in Africa (Gabun events) and other
places in Precambrian deposits. Further most Uranium and Radium deposits exhibit plenty
traces of extinct lfe forms. This way it can be clearly concluded, that from the early periods of
onset of life until today many microorganism types, among which bacteria and fungi
predominantly are capable of surviving extremely high doses of radiation. In addition it has
been convincingly shown by experiments, that bacteria, cyanobacteria and fungi are capable
of enriching radioactive elements to levels of concentrations which may initiate natural
nuclear events such as the nuclear reactors of Gabun. The ore deposit of Menzenschwand in
the black forest of Germany is loaded with microbial fossils indicating that one of the major
pathways of ore enrichment is microbial accumulation of radioactive elements by way of
metabolic processes and cell wall catchment of heavy elements. The same has been shown for
iridium, platinum and gold. V. I. Vernadsky was one of the fore-runners of ideas concerning
radiation biology as also N.V. Timofeev-Ressovsky. In Ukrainia some mycologists have also
studied the survival potential of black yeast like fungi after the radioactivity release event of
the Tschernobyl reactors. N. N. Lyalikova of the INMI, Moskwa as well as B.D. Dyer of BU,
Boston have worked on the enrichment of radioactive elements and of iridium from atomic
waste deposits in Russia. From their and our findings we derive, that not only prokaryotes, but
also fungi have a high capability of not only surviving high doses of radioactivity but also to
enrich radioactive elements in the cell vicinity and hereby helping to create radioactive ore
deposits by ways of metabolic activity.