WC Archive

Geobacter sulfurreducens -- get used to seeing that name. It may well be the key to cleaning up some of the most dangerous radioactive wastes sites around. Best of all, it's completely natural.

G. sulfurreducens is a microbe that is able to turn the soluble form of uranium contaminating groundwater around nuclear weapons production sites (such as Rifle Mill in Colorado) into an easily-collected precipitate. Researchers with the Department of Energy have managed to use the bacteria to reduce uranium in the groundwater around Rifle Mill by 90%. The microbe occurs naturally in the ground; its growth is stimulated by adding vinegar to the soil.

But now, biologists at The Institute for Genomic Research (TIGR) in Rockville, Maryland, have sequenced the microbe's DNA, figuring out how it manages to detect and "eat" uranium, producing minute amounts of electricity. Their report is in today's edition of Science; the illustration at right is from their online supporting material. TIGR and University of Massachusetts in Amherst researchers believe that they will be able to manipulate the microbe's genome to make its uranium-electricity conversion faster and more efficient.

(It's worth noting that G. sulfurreducens doesn't make the uranium go away; it makes it no longer soluble in water. This is an ideal type of bacterial bioremediation -- the contaminant becomes easy to clean up, but there's no risk of the microbe "running wild" and devouring otherwise safe material.)