Among the most common inorganic contaminants at these sites are the elements uranium, plutonium, technetium, and chromium. All of these are less mobile when reduced by microorganisms. However, some contaminated sediments and soils at DOE sites, particularly beneath leaking waste storage tanks, can have radiation levels that exceed those tolerated by most microorganisms. It might be the only known microorganism that can survive such conditions and may someday be used to remediate highly radioactive waste. The durability of this microorganism testifies that it is better able to repair its radiation-damaged DNA than other organisms.
Proteomics is the study of proteins that are expressed by the genetic array of an organism.
The researchers used unique high magnetic field Fourier transform ion cyclotron resonance mass spectrometry at PNNL's Environmental Molecular Science Laboratory to identify the microbe's proteins. Their methods allowed them to precisely measure the expression levels for all proteins in a single experiment. They are currently using the same approach to track changes in protein-expression patterns after D. radiodurans has been exposed to ionizing radiation. In such situations, D. radiodurans may be effective at reducing contaminants such as chromium and uranium in place, thus preventing their migration through soils and into ground water. Microbes of the deinococci family appear to be widely distributed in soils and have been routinely isolated from organically rich as well as dry, nutrient-poor environments.