Microbial Life at High Radiation Levels

Created by: Scott N. Montross, Montana State University

"Bacteria of the genus Deinococcus exhibit an extraordinary ability to withstand the lethal and mutagenic effects of DNA damaging agents-particularly the effects of ionizing radiation. These bacteria are the most DNA damage-tolerant organisms ever identified."

-Battista, J.R. (1997) Annual Review of Microbiology: v. 51

Why are radioactive tolerant bacteria so special?

Resistance to radiation was first discovered by scientists who were interested in food sterilization. After multiple experiments using high doses of radiation certain bacterial communities persisted, one which was named Dienococcus radiodurans. These unusual bacteria are very highly resistant to what scientists had considered to be absolutely lethal radiation levels. Deinococcus radiodurans is remarkable for its ability to withstand radiation levels 100-1000 times higher than that which would completely debilitate any human on earth.

It has been discovered that Deinococcus is as resistant to complete dehydration as it is to radiation, and shows similar response to extremely dry conditions as in highly radioactive environments. In fact, researchers believe the resistance of Deinococcus to radiation is only incidental to the discovery and development of radiation emitting technology, and that dehydration resistance may have evolutionarily preceeded radiation resistance.

Radiation Collections

General Collection: Resources such as news articles, web sites, and reference pages provide a comprehensive array of information about radiation tolerant microbes.

For Educators: This collection includes activities, assignments, and reading materials created specifically for educators.

Advanced Collection: Compiled for professionals and advanced learners, this collection includes resources such as journal articles, academic reviews, and surveys.

Additional Resources

For additional resources about Microbial Life in Radioactive Environments, search the Microbial Life collection