Bacteria may be a key in containing radioactive contamination and other environmental pollutants. A naturally occurring bacteria found in soil called Geobacter has been known to be useful in contaminated soil cleanup, but the process by which it prevents the spread of pollutants has not been known until the work of Gemma Reguera and her team of researchers at Michigan State University identified how the the bacteria concentrates contaminants.
The bacteria have nanowire structures called pili, which are like fine hair on the exterior of the bacterial cells. In a toxic waste site contaminated with uranium, these nanowires essentially become electroplated by the uranium. This process contains it and renders it insoluble, so that it cannot be dissolved and taken up by groundwater.
“This tiny microorganism can play a major role in cleaning up polluted sites around the world,” Reguera says. “Uranium contamination can occur at any step in the cycle of production of nuclear fuel – from mining, processing and enrichment to accidental spills from the nuclear plant. Contamination can spread fast and stay in the environment for many, many years. However, you can stimulate the natural Geobacter community of the soil and groundwater, or feed the improved strains in the environment. The bacteria will oxidize and precipitate the uranium.”
The pili also serve to protect the bacteria from the uranium, which is toxic, by keeping it outside the cell. The researchers are now working to develop strains of Geobacter with increased pili production to make it more effective for this type of remediation work.
via: MSU News
written by nerkn, September 18, 2011
written by Isaac5, September 19, 2011
written by MrFoster, September 20, 2011
|< Prev||Next >|