Superbug Survives Radiation, Eats Toxic Waste
DOE Microbial Genome Program Report
A can of spoiled meat and nuclear waste may appear to have little in common, but the bacterium Deinococcus radiodurans thrives in both environments. This bacterium was discovered in 1956 when it was identified as the culprit in a can of spoiled ground beef thought to be radiation ”sterilized.” Scientists subsequently learned that its extreme radiation resistance enables the microbe to survive doses thousands of times higher than would kill most organisms, including humans. The remarkable DNA-repair processes of  D. radiodurans allow it to stitch together flawlessly its own radiation-shattered genome in about 24 hours.

DOE chose this organism for DNA sequencing because of its potential usefulness in cleaning up waste sites containing radiation and toxic chemicals. Its DNA sequence was completely determined in 1999, and scientists now are exploring ways to add genes from other organisms to expand D. radiodurans’ capabilities for removing toxic wastes from contaminated sites. The added genes encode proteins that transform heavy metals to a more benign biomass and allow the concentration of heavy metals and the breakdown of organic solvents such as toluene. Studies into this organism’s remarkable DNA-repair pathways also may help scientists better understand how defects in human cellular processes might lead to the development of cancers.
 
The online presentation of this 2000 publication is a special feature of the Human Genome Project Information Web site.