Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Engineering Deinococcus radiodurans for metal remediation in radioactive mixed waste environments


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.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type



Prices may be subject to local taxes which are calculated during checkout

Figure 1: Plasmid and chromosomal maps.
Figure 2: Construction and structure of a chromosomal direct insertion of the mer operon.
Figure 3: Determination of mer operon copy number and associated mercury resistance phenotype.
Figure 4: Effect of continuous exposure to γ-radiation and Hg (II) on the growth of strains, containing different copy numbers of the mer operon.
Figure 5: Construction and characterization of a mercury resistant and toluene metabolizing D. radiodurans.
Figure 6: (A) Mercuric reductase assay.

Similar content being viewed by others


  1. Riley, R.G., Zachara, J.M. & Wobber, F.J. Chemical contaminants on DOE lands and selection of contaminant mixtures for subsurface science research. US Dept. of Energy, Office of Energy Research, Subsurface Science Program, Washington, DC 20585 (1992).

    Google Scholar 

  2. McCullough, J., Hazen, T., Benson, S., Blaine-Metting, F. & Palmisano, A.C. Bioremediation of metals and radionuclides, US Dept. of Energy, Office of Biological and Environmental Research, Germantown, MD 20874 (1999).

    Book  Google Scholar 

  3. Macilwain, C. Science seeks weapons clean-up role. Nature 383, 375–379 (1996).

    CAS  Google Scholar 

  4. The 1996 Baseline Environmental Management Report.

  5. Gorby, Y.A. & Lovley, D.R. Enzymatic uranium reduction. Environ. Sci. Technol. 26, 205–207 (1992).

    Article  CAS  Google Scholar 

  6. Higham, D.P., Sadler, P.J. & Scawen, M.D. Cadmium-resistant Pseudomonas putida synthesizes novel cadmium proteins. Science 225, 205– 207 (1984).

    Article  Google Scholar 

  7. Ji, G. & Silver, S. Regulation and expression of arsenic resistance operon from Staphylococcus aureus plasmid pI258. J. Bacteriol. 174, 3684–3694 (1992).

    Article  CAS  Google Scholar 

  8. Lovely, D.R. Bioremediation of organic and metal contaminants with dissimilatory metal reduction. J. Ind. Microbiol. 14, 85– 93 (1995).

    Article  Google Scholar 

  9. Nies, D.H. & Silver, S. Ion efflux systems involved in bacterial metal resistances. J. Ind. Microbiol. 14, 186–199 (1992).

    Article  Google Scholar 

  10. Tsapin, A.I. et al. Purification and properties of a low-redox-potential tetraheme cytochrome c3 from Shewanella putrefaciens. J. Bacteriol. 178, 6386–6388 (1996).

    Article  CAS  Google Scholar 

  11. Turner, J.S. & Robinson, N.J. Cyanobacterial metallothioneins: biochemistry and molecular genetics. J. Ind. Microbiol. 14, 119–125 (1995).

    Article  CAS  Google Scholar 

  12. Voordouw, G. & Brenner, S. Cloning and sequencing of the gene encoding cytochrome c3 from Desulfovibrio vulgaris (Hildenborough). Eur. J. Biochem. 159, 347 –351 (1986).

    Article  CAS  Google Scholar 

  13. Thornley, M.J. Radiation resistance among bacteria. J. Appl. Bacteriol. 26, 334–345 (1963).

    Article  Google Scholar 

  14. Rugh, C.L., Senecoff, J.F., Meagher, R.B. & Merkle, S.A. Development of transgenic yellow poplar for mercury phytoremediation. Nat. Biotechnol. 16, 925–928 (1998).

    Article  CAS  Google Scholar 

  15. Rugh C.L. et al. Mercuric ion reduction and resistance in transgenic Aribidopsis thaliana plants expressing a modified merAgene. Proc. Natl. Acad. Sci. USA 93, 3182–3187 (1996).

    Article  CAS  Google Scholar 

  16. Brooks, B.W. et al. Red-pigmented micrococci: a basis for taxonomy. Int. J. Syst. Bacteriol. 30, 627–646 (1980).

    Article  Google Scholar 

  17. Minton, K.W. Repair of ionizing-radiation damage in the radiation resistant bacterium Deinococcus radiodurans. Mutat. Res. DNA Repair 362, 1–7 (1996).

    Article  Google Scholar 

  18. Daly, M.J., Ouyang, L. & Minton, K.W. In vivo damage and recA-dependent repair of plasmid and chromosomal DNA in the radioresistant bacterium Deinococcus radiodurans. J. Bacteriol. 176, 3508 –3517 (1994).

    Article  CAS  Google Scholar 

  19. White, O. et al. Complete genome sequencing of the radioresistant bacterium Deinococcus radiodurans R1. Science 286, 1571– 1577 (1999).

    Article  CAS  Google Scholar 

  20. Hansen, M.T. Multiplicity of genome equivalents in the radiation-resistant bacterium Micrococcus radiodurans. J. Bacteriol. 134, 71–75 (1978).

    CAS  PubMed  PubMed Central  Google Scholar 

  21. Lange, C.C., Wackett, L.P., Minton, K.W. & Daly, M.J. Engineering a recombinant Deinococcus radiodurans for organopollutant degradation in radioactive mixed waste environments. Nat. Biotechnol. 16, 929–933 ( 1998).

    Article  CAS  Google Scholar 

  22. Summers A.O. Organization, expression, and evolution of genes for mercury resistance. Annu. Rev. Microbiol. 40, 607–634 (1986).

    Article  CAS  Google Scholar 

  23. Schottel J.L. The mercuric and organomercurial detoxifying enzymes from a plasmid-bearing strain of Esherichia coli. J. Biol. Chem. 253 , 4341–4349 (1978).

    CAS  PubMed  Google Scholar 

  24. Barrineau, P. et al. The structure of the mer operon. Basic Life Sci. 30, 707–718 ( 1985)

    CAS  PubMed  Google Scholar 

  25. Daly, M.J., Ouyang, L. & Minton, K.W. Interplasmidic recombination following irradiation of the radioresistant bacterium Deinococcus radiodurans. J. Bacteriol. 176, 7506–7515 (1994).

    Article  CAS  Google Scholar 

  26. Altschul, S.F. et al. Gapped BLAST and PSI-BLAST: a new generation of protein database search programs. Nucleic Acids Res. 25, 3389–3402 (1997).

    Article  CAS  Google Scholar 

  27. Smith, M.D., Lennon, E., McNeil, L.B. & Minton, K.W. Duplication insertion of drug resistance determinants in the radioresistant bacterium Deinococcus radiodurans. J. Bacteriol. 170, 2126 –2135 (1988).

    Article  CAS  Google Scholar 

  28. Daly, M.J. & Minton, K.W. An alternative pathway for recombination of chromosomal fragments precedes recA-dependent recombination in the radioresistant bacterium Deinococcus radiodurans. J. Bacteriol. 178, 4461–4471 (1996).

    Article  CAS  Google Scholar 

  29. Daly, M.J. & Minton K.W. Interchromosomal recombination in the extremely radioresistant bacterium Deinococcus radiodurans. J. Bacteriol. 177, 5495–5505 (1995).

    Article  CAS  Google Scholar 

  30. Fox, B. & Walsh, C.T. Mercuric reductase. Purification and characterization of a transposon-encoded flavoprotein containing an oxidation-reduction-active disulfide. J. Biol. Chem. 257, 2498– 2503 (1982).

    CAS  PubMed  Google Scholar 

  31. Chang, J.S., Chao, Y.P., Law W.S. Repeated fed-batch operations for microbial detoxification of mercury using wild-type and recombinant mercury-resistant bacteria. J. Biotechnol. 64, 219–230 ( 1998).

    Article  CAS  Google Scholar 

  32. Kobal, V.M., Gibson, D.T., Davis, R.E. & Garza, A. X-ray determination of the absolute stereochemistry of the initial oxidation product formed from toluene by Pseudomonas putida 39-D. J. Am. Chem. Soc. 95, 4420–4421 (1973).

    Article  CAS  Google Scholar 

  33. Nakamura, K. & Nakahara, H. Simplified X-ray film method for detection of bacterial volatilization of mercury chloride by Escherichia coli. Appl. Environ. Microbiol. 54, 2871–2873 (1988).

    CAS  PubMed  PubMed Central  Google Scholar 

  34. Gibson, D.T., Cardini, G.E., Maseles, F.C. & Kallio, R.E., Incorporation of oxygen-18 into benzene by Pseudomonas putida. Biochemistry 9, 1631–1635 ( 1970).

Download references


This research was largely funded by grant DE-FG02-97ER62492 from the Natural and Accelerated Bioremediation Research program, Office of Biological and Environmental Research, DOE. Some of this work was also supported by the grant DE-FG07-97ER20293 and DE-FG02-98ER62583 from the DOE; and grant MDA-905-97-Z-0053 from the U.S. Department of Defense.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Michael J. Daly.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Brim, H., McFarlan, S., Fredrickson, J. et al. Engineering Deinococcus radiodurans for metal remediation in radioactive mixed waste environments. Nat Biotechnol 18, 85–90 (2000).

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI:

This article is cited by


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing