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Arokiasamy J. (AJ) Francis


Microbiologist Arokiasamy J. (A.J.) Francis, retired from the Environmental & Climate Sciences Department in 2011 and was named Scientist Emeritus in 2012. During his nearly 37 years at Brookhaven National Laboratory, he has concentrated on the realm of microbial interactions with organic and inorganic contaminants — and their remediation. Francis’ investigations have ranged from nitrogen cycling and the control of nitrate pollution to the transformation of radioactive contaminants in the environment. The latter became his primary research focus, taking shape in many different projects, including his groundbreaking work with the use of citric acid to sequester uranium from contaminated soils, wastes and materials.

Francis first came to Brookhaven in 1975 as a microbiologist on a project to remove nitrate from wastewater and prevent ground and surface water contamination. The project’s funding was not renewed, but Francis found his footing in a new realm of interest, in which he studied how microbes transformed radionuclides and toxic materials found in nuclear energy and fossil-fuel wastes.


  • Cornell University, Ph.D., Microbiology
  • Annamalai University, M.Sc., Soil Microbiology; B.Sc., Agriculture

Professional Affiliations

  • Adjunct Professor, Department of Materials Science and Engineering, State University of New York, at Stony Brook
  • American Society for Microbiology
  • Korean Nuclear Society
  • American Chemical Society

Areas of Interest

  • Microbial transformations of radionuclides, toxic metals, and organic compounds in wastes and in subsurface environments
  • Biodegradation of organic-metal/radionuclide complexes, pesticides and organic pollutants
  • Nitrogen transformation in soils
  • Microbial gas generation from radioactive wastes
  • Bioremediation of radionuclides and toxic metals contaminated soils and wastes
  • Decontamination of radionuclide contaminated steels and materials


  •  Patent US 8,158,399 B2, “Extracellular Bioreduction”,  April 17, 2012.


  • Organized a round table symposium on "Microbial Aspects of Transuranic and other Radioactive Wastes" (convener), American Society for Microbiology
  • Previous experience at Stanford Research Institute involved studies on the microbiological degradation of military standard pesticide formulations, and at Cornell University on symbiotic nitrogen fixation in legumes and life detection (exobiology) by GC-MS of microbial metabolites
  • Consultant to: FAO of U.N. in Agricultural and Environmental Microbiology
  • Directorate of Plant Protection, Ministry of Agriculture, India, under Indo-U.S. Aid Program; UNDP-TOKTEN Project
  • Advisory Panel member, WIPP Program-Sandia National Laboratory; Member of the Board of Examiners, Ph.D. degree, Napier College, Edinburgh, U.K.
  • Annamalai University, India; Bharathiar University, India
  • Team member, DOE Biotechnology Team, RDDT & E Five-Year Plan. Invited participant and contributor to U.S. DOE Office of Energy Research (DOE/ER-0482T, 1990; DOE/ER-0492T, 1991)
  • Invited participant of the European group MIND (Microbiology in Nuclear Waste Disposal)
  • Technical Committee Member, IAEA on "Advanced Technologies for Treatment of Low and Intermediate Low-level Radioactive Liquid Wastes."
  • Invited participant at the Microbiology of Nuclear Waste Disposal Concept Tutorial, Scientific Review Group, Canada, 1993.
  • Invited speaker at the Actinides '93 Conference, Santa Fe, NM, 1993
  • Invited key speaker NATO ARW on Biotechnologies for Radioactive and Toxic Waste Management and Site Restoration, Mol, Belgium, 1994
  • Invited speaker at the Actinides '97 International Conference, Baden-Baden, Germany, 1997
  • Foreign Distinguished Scientist Inviting Program, Japan Atomic Energy Research Institute, March 28-April 28, 1998 and September 1-30, 2000
  • Consultant to Nuclear Fuel Industries, Ltd., (NFI), Tokai, Japan (1999)
  • Advisor: Actinide Migration Evaluation (AME) Group, The Rocky Flats Environmental Technology Site, Rocky Flats, CO (2000-present)
  • Scientific Advisor, Advanced Science Research Center, Japan Atomic Energy Research Institute, Tokai, Japan

Publications (since 2000)

Choung, S., Um, W., Choi, S., Francis, A. J., Kim, S., Park, J. B., and Kim, S.-H. Biogeochemical changes at early stage after the closure of radioactive waste geological repository in South Korea. Annals of Nuclear Energy 71, 6-10, doi:10.1016/j.anucene.2014.03.021 (2014).

Zhang, C., Malhotra, S. V., and Francis, A. J. Toxicity of ionic liquids to Clostridium sp. and effects on uranium biosorption. J. Hazardous Materials 264, 246-253, doi:10.1016/j.jhazmat.2013.11.003 (2014).

Gao, W. and Francis, A. J. Fermentation and Hydrogen Metabolism Affect Uranium Reduction by Clostridia. ISRN Biotechnology 2013, Article ID 657160, doi:10.5402/2013/657160 (2013).

Thakur, P., Conca, J. L., Dodge, C. J., Francis, A. J., and Choppin, G. R. Complexation thermodynamics and structural studies of trivalent actinide and lanthanide complexes with DTPA, MS-325 and HMDTPA. Radiochim. Acta 101, 221-232, doi:10.1524/ract.2013.2018 (2013).

Zhang, C., Dodge, C. J., Malhotra, S. V., and Francis, A. J. Bioreduction and precipitation of uranium in ionic liquid aqueous solution by Clostridium sp. Bioresource Technol. 136, 752-756, doi:10.1016/j.biortech.2013.03.085 (2013).

Francis, A. J. Impacts of microorganisms on radionuclides in contaminated environments and waste materials. In Radionuclide Behaviour in the Natural Environment: Science, Implications and Lessons for the Nuclear Industry, C. Poinssot and H. Geckeis, Eds., Woodhead Publishing Series in Energy, pp. 161-225, Woodhead Publishing Limited, Cambridge, UK and Philadelphia, PA, 2012.

Yarlagadda, V. N., Gupta, A., Dodge, C. J., and Francis, A. J. Effect of exogenous electron shuttles on growth and fermentative metabolism in Clostridium sp. BC1. Bioresource Technol. 108, 295-299 (2012).

Gillow, J. and Francis, A. Microbial Gas Generation Under Expected Waste Isolation Pilot Plant Repository Conditions: Final Report. Informal Report, BNL-96148-2011-IR, July 2011.

Nancharaiah, Y. and Francis, A. Alkyl-methylimidazolium ionic liquids affect the growth and fermentative metabolism of Clostridium sp. Bioresource Technol. 102, 6573-6578 (2011).

Thakur, P., Mathur, J. N., Dodge, C. J., Francis, A. J., and Choppin, G. R. Thermodynamics and the structural aspects of the ternary complexes of Am(III), Cm(III) and Eu(III) with Ox and EDTA + Ox. Dalton Trans., 4829-4837 (2006).

Suzuki, Y., Nankawa, T., Yoshida, T., Ozaki, T., Ohnuki, T., Francis, A. J., Tsushima, S., Enokida, Y., and Yamamoto, I. Reduction behavior of uranium in the presence of citric acid. Radiochemica Acta 94, 579-583, doi:10.1524/ract.2006.94.9.579 (2006).

Ozaki, T., Suzuki, Y., Nankawa, T., Yoshida, T., Ohnuki, T., Kimura, T., and Francis, A. J. Interactions of rare earth elements with bacteria and organic ligands. J. Alloys Compounds 408-412, 1334-1338 (2006).

Ozaki, T., Kimura, T., Ohnuki, T., and Francis, A. J. Effects of Ionic Strength on the Coordination of Eu(III) and Cm(III) to a Gram-Negative Bacterium, Paracoccus denitrificans. Radiochemica Acta 94, 715-721, doi:10.1524/ract.2006.94.9.715 (2006).

Nankawa, T., Suzuki, Y., Ozaki, T., Ohnuki, T., and Francis, A. J. Degradation of Eu(III)-malic acid complexes by Pseudomonas fluorescens. J. Alloys Comp. 408-412, 1329-1333 (2006).

Mathur, J. N., Thakur, P., Dodge, C. J., Francis, A. J., and Choppin, G. R. Coordination Modes in the Formation of the Ternary Am(III), Cm(III), and Eu(III) Complexes with EDTA and NTA: TRLFS, 13C NMR, EXAFS, and Thermodynamics of the Complexation. Inorganic Chem. 45, 8026-8035, doi:10.1021/ic052166c (2006).

Francis, A. J., Dodge, C. J., and Gillow, J. B. Biotransformation of plutonium complexed with citric acid. Radiochimica Acta. 94, 731-737, doi:10.1524/ract.2006.94.9.731 (2006).

Barak, Y., Ackerley, D. F., Dodge, C. J., Banwari, L., Alex, C., Francis, A. J., and Matin, A. Analysis of novel soluble chromate and uranyl reductases and generation of an improved enzyme by directed evolution. Applied Environ. Microbiology 72, 7074-7082, doi:10.1128/AEM.01334-06 (2006).

Yoshida, T., Ozaki, T., Ohnuki, T., and Francis, A. J. Adsorption of Th(IV) and Pu(IV) on the surface of pseudomonas fluorescensand bacillus subtilisin the presence of desferrioxamine siderophore. J. Nuclear Radiochem. Sci. 6, 77-80 (2005).

Wang, Y. and Francis, A. J. Evaluation of microbial activity for long-term performance assessments of deep geologic nuclear waste repositories J. Nuclear Radiochem. Sci. 6, 43-50 (2005).

Suzuki, Y., Nankawa, T., Yoshida, T., Ozaki, T., Ohnuki, T., Francis, A. J., Tsushima, S., Enokida, Y., and Yamamoto, I. Sorption of Eu(III) on pseudomonas fluorescensin the presence of citric acid J. Nuclear Radiochem. Sci. 6, 91-93 (2005).

Suzuki, Y., Nankawa, T., Yoshida, T., Ozaki, T., Ohnuki, T., Francis, A. J., Tsushima, S., Enokida, Y., and Yamamoto, I. Biodegradation of Eu(III)-citrate complexes by pseudomonas fluorescens J. Radioanal. Nuclear Chem. 266, 199-204 (2005).

Sakamoto, F., Ohnuki, T., Kozai, N., Wakai, E., Fujii, T., Iefuji, H., and Francis, A. J. Effect of Uranium (VI) on the growth of yeast and influence of metabolism of yeast on adsorption of U (VI) J. Nuclear Radiochem. Sci. 6, 99-101 (2005).

Ozaki, T., Kimura, T., Ohnuki, T., and Francis, A. J. Associations of Eu(III) with gram-negative bacteria, alcaligenesfaecalis, schwanella putrefaciens, and paracoccus denitrificans. J. Nucl. Radiochem. Sci. 6, 73-76 (2005).

Ozaki, T., Ambe, S., Abe, T., and Francis, A.J. Competitive inhibition and selectivity enhancement by Ca in the uptake of inorganic elements (Be, Na, Mg, K, Ca, Sc, Mn, Co, Zn, Se, Rb, Sr, Y, Zr, Ce, Pm, Gd, Hf) by Carrot (Daucus Carota) cv. U.S. harumakigosun). J. Biolog. Trace Element Res. 13, 69-82 (2005).

Ohnuki, T., Yoshida, T., Nankawa, T., Ozaki, T., Kozai, N., Sakamoto, F., Suzuki, Y., and Francis, A. J. A continuous flow system for in-situ XANES measurements of change in oxidation state of Ce(III) to Ce(IV). J. Nucl. Radiochem. Sci. 6, 65-67 (2005).

Ohnuki, T., Ozaki, T., Yoshida, T., Sakamoto, F., Kozai, N., Wakai, E., Francis, A. J., and Iefuji, H. Mechanisms of uranium mineralization by the yeast saccharomyces cerevisiae. Geochimica et Cosmochimica Acta 69, 5307-5316 (2005).

Nankawa, T., Suzuki, Y., Ozaki, T., Ohnuki, T., and Francis, A. J. Effect of Eu(III) on the degradation of Malic acid by Pseudomonas fluorescenscand the subsequent production of Pyruvic acid. J. Nucl. Radiochem. Sci. 6, 95-98 (2005).

Lerotic, M., Jacobsen, C., Gillow, J.B., Francis, A.J., Wirick, S., Vogt, S., and Maser, J. Cluster analysis in soft x-ray spectromicroscopy: finding the patterns in complex specimens. J. Electron Spectrosc. Rel. Phenom. 144-147, 1137-1143 (2005).

Kantar, C., Gillow, J. B., Harper-Arabie, R., Honeyman, B. D., and Francis, A. J. Determination of stability constants of U(VI)-Fe(III)-Citrate complexes. Environ. Sci. Technol. 39, 2161-2168, doi:10.1021/es048852c (2005).

Francis, A. J., Dodge, C. J., McDonald, J. A., Halada, G. P., and Eng, C. W. Decontamination of uranium contaminated steel surfaces by hydroxycarboxylic acids with uranium recovery. Environ. Sci. Technol. 39, 5015-5021,doi:10.1021/es048887c (2005).

Ozaki, T., Gillow, J. B., Kimura, T., Ohnuki, T., Yoshida, Z., and Francis, A. J. Sorption behavior of Europium(III) and Curium(III) on the cell surfaces of microorganisms. Radiochimica Acta 92, 741-748, doi:10.1524/ract.92.9.741.55006 (2004).

Ohnuki, T., Sakamoto, F., Kozai, N., Ozaki, T., Yoshida, T., Narumi, I., Wakai, E., Sakai, T., and Francis, A.J. Mechanisms of arsenic immobilization in a biomat from mine discharge water. J. Chem. Geology 212, 279-290 (2004).

Eng, C. W., Halada, G. P., Francis, A. J., and Dodge, C. J. Spectroscopic study of decontaminated corroded carbon steel surfaces. Surface Interface Analysis 36, 1516-1522 (2004).

Ozaki, T., Ambe, S., Abe, T., and Francis, A.J. Uptake of short half-life radionuclides, 28Mg, 43K and 47Ca, in carrot studied by the multitracer technique: Feasibility of utilization of the radionuclides in environmental research. J. Radioanalyt. Nuc. Chem. 258, 89-92 (2003).

Ozaki, T., Kimura, T., Ohnuki, T., Yoshida, Z., and Francis, A.J. Association mechanisms of Europhium(III) and Curium(III) with Chlorella Vulgaris. J. Environ. Toxicol. Chem. 22, 273-278 (2003).

Ohnuki, T., Sakamoto, F., Kozai, N., Ozaki, T., Narumi, I., Francis, A.J., Iefuji, H., Sakai, T., Kamiya, T., Satoh, T., and Oikawa, M. Application of micro-PIXE technique to uptake study of cesium by Saccharomyces cerevisiae. J. Nuclear Instru. Methods .Phys. Res. B 210, 378-382 (2003).

Eng, C. W., Halada, G. P., Francis, A. J., Dodge, C. J., and Gillow, J. B. Uranium association with corroding carbon steel surfaces. J. Surface Interface Anal. 35, 525-535 (2003).

Dodge, C. J. and Francis, A. J. Structural characterization of a ternary Fe(III)-U(VI)-citrate complex. Radiochimica Acta 91, 525-532 (2003).

Francis, A. J., Dodge, C. J., and Meinken, G. E. Biotransformation of pertechnetate by Clostridia. Radiochimica Acta 90, 09-11, doi:10.1524/ract.2002.90.9-11_2002.791 (2002).

Dodge, C. and Francis, A. J. Photodegradation of a ternary Iron(III)-Uranium(VI)-Citric acid complex. Environ. Sci. Technol. 36, 2094-2100 (2002).

Dodge, C. J., Francis, A. J., Gillow, J. B., and Papenguth, H. W. Biotransformation of uranium compounds in high ionic strength brine by a halophilic bacterium under denitrifying conditions. Environ. Sci. Technol. 34, 2311-2317, doi:10.1021/es991251e S0013-936X(99)01251-1 (2000).