Engineering Deinococcus radiodurans for metal remediation in radioactive mixed waste environments

Nat Biotechnol. 2000 Jan;18(1):85-90. doi: 10.1038/71986.


We have developed a radiation resistant bacterium for the treatment of mixed radioactive wastes containing ionic mercury. The high cost of remediating radioactive waste sites from nuclear weapons production has stimulated the development of bioremediation strategies using Deinococcus radiodurans, the most radiation resistant organism known. As a frequent constituent of these sites is the highly toxic ionic mercury (Hg) (II), we have generated several D. radiodurans strains expressing the cloned Hg (II) resistance gene (merA) from Escherichia coli strain BL308. We designed four different expression vectors for this purpose, and compared the relative advantages of each. The strains were shown to grow in the presence of both radiation and ionic mercury at concentrations well above those found in radioactive waste sites, and to effectively reduce Hg (II) to the less toxic volatile elemental mercury. We also demonstrated that different gene clusters could be used to engineer D. radiodurans for treatment of mixed radioactive wastes by developing a strain to detoxify both mercury and toluene. These expression systems could provide models to guide future D. radiodurans engineering efforts aimed at integrating several remediation functions into a single host.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Dose-Response Relationship, Drug
  • Drug Resistance, Microbial / genetics
  • Drug Resistance, Microbial / physiology
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Gamma Rays
  • Gene Dosage
  • Genes, Bacterial / genetics
  • Genetic Engineering*
  • Genetic Vectors / genetics
  • Gram-Positive Cocci / drug effects
  • Gram-Positive Cocci / genetics*
  • Gram-Positive Cocci / metabolism*
  • Inactivation, Metabolic
  • Ions
  • Mercury / metabolism*
  • Mercury / toxicity
  • Operon / genetics
  • Oxidation-Reduction
  • Oxidoreductases / genetics
  • Oxidoreductases / metabolism
  • Radiation Tolerance / genetics
  • Radiation Tolerance / physiology
  • Radioactive Waste*
  • Toluene / metabolism
  • Toluene / toxicity
  • Transformation, Bacterial
  • Waste Management*


  • Bacterial Proteins
  • Ions
  • Radioactive Waste
  • Toluene
  • Oxidoreductases
  • mercuric reductase
  • Mercury