U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights

"Conan the Bacterium's" Secrets Illuminated; Insights into How Deinococcus radiodurans Resists Extreme Doses of Radiation
Published: September 27, 2004
Posted: October 12, 2004

The bacterium Deinococcus radiodurans was discovered in 1957 in a can of meat that had been irradiated in order to sterilize it for longer shelf life. Typically, cultures of Deinococcus (sometimes called "Conan the Bacterium") can withstand up to a million Rads (10,000 Grays) of ionizing radiation, roughly 2000 times the LD50 for humans. Exactly what mechanisms Deinococcus radiodurans uses to repair all the breaks in its DNA caused by radiation at this dose level remains poorly understood but recent work by Michael Daly, of the Uniformed Services University of the Health Sciences in Bethesda, MD, is providing some intriguing clues. In work supported by the Office of Biological and Environmental Research's (BER) Natural and Accelerated Bioremediation Research and Microbial Genome Programs, and grounded in the availability of the complete genome sequence of this bacterium (determined by The Institute for Genomic Research with BER funding), Daly and collaborators find that Deiococcus radiodurans cells accumulate very high intracellular levels of manganese (Mn) but display extremely low levels of iron (Fe), suggesting a protective role for the Mn and a deleterious role for the Fe. This work is scheduled for publication on September 30 in ScienceExpress, a service of Science, with print publication to follow a few weeks after that. Furthermore, a similar profile of levels of these elements is found in other relatively radioresistant bacteria. This work suggests that radiation resistance could be altered by adjusting intracellular Mn and/or Fe levels. In human cancer therapies, treatments with agents reducing Mn or increasing Fe potentially could increase the radiosusceptibility of targeted cells thus improving prospects for survival.

Contact: Dan Drell, SC-72, (301) 903-4742
Topic Areas:

  • Research Area: Genomic Analysis and Systems Biology
  • Research Area: Microbes and Communities
  • Legacy: Medical Applications

Division: SC-23.2 Biological Systems Science Division, BER
      (formerly SC-72 Life Sciences Division, OBER)


BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

Aug 24, 2019
New Approach for Studying How Microbes Influence Their Environment
A diverse group of scientists suggests a common framework and targeting of known microbial processes [more...]

Aug 08, 2019
Nutrient-Hungry Peatland Microbes Reduce Carbon Loss Under Warmer Conditions
Enzyme production in peatlands reduces carbon lost to respiration under future high temperatures. [more...]

Aug 05, 2019
Amazon Forest Response to CO2 Fertilization Dependent on Plant Phosphorus Acquisition
AmazonFACE Model Intercomparison. The Science Plant growth is dependent on the availabi [more...]

Jul 29, 2019
A Slippery Slope: Soil Carbon Destabilization
Carbon gain or loss depends on the balance between competing biological, chemical, and physical reac [more...]

Jul 15, 2019
Field Evaluation of Gas Analyzers for Measuring Ecosystem Fluxes
How gas analyzer type and correction method impact measured fluxes. The Science A side- [more...]

List all highlights (possible long download time)