The red-coloured bacterium Deinococcus radiodurans can resist 1.5 million rads of gamma radiation, about 3,000 times the amount that would kill a human. The bacterium survives and reproduces in environments that would be lethal for any other organism and it also resists high doses of ultraviolet radiation.
The most important component of this radiation resistance is the ability of the bacteria to repair damage to its chromosomal DNA. Researchers hope that they can manipulate it in such a way that it will be able to detoxify the thousands of toxic waste sites which contain radioactive material. Only in the US, 10 million cubic yards of radioactive wastes have contaminated about 70 million cubic yards of soil and some 1 trillion gallons of ground water.
The bacteria was first isolated from cans of meat that were subjected to supposedly sterilising doses of radiation in the megarad range.
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