BER Research Highlights

Search Date: April 29, 2017

7 Records match the search term(s):


December 05, 2001

NABIR Researcher Invited to Present at Three International Meetings (Austria, Japan, Germany)

Mary Neu, Los Alamos National Laboratory, described her work on the biological chelation and reduction of plutonium (Pu) in subsurface soil environments at 1) the Eighth International Conference on the Migration of Radionuclides in the Geosphere in Austria, 2) the Actinides-2001 Conference in Japan, and 3) the Gotenburg University in Germany. Her work is critical to understanding the fate of radionuclides released to soil environments, and to the development of new biotechnologies to migrate radionuclides at DOE sites. Her research is receiving much deserved national and international professional recognition. She has been invited to speak at a new Gordon Conference on Environmental Bioinorganic Chemistry (to be held in New Hampshire), and to organize a session for the 23rd Rare Earth Conference (to be held in California). She has also initiated a collaboration with the European Centre d'Energie Atomique.

Contact: Brendlyn Faison, SC-74, 3-0042
Topic Areas:

Division: SC-23.1 Climate and Environmental Sciences Division, BER
      (formerly SC-74 Environmental Sciences Division, OBER)


August 01, 2001

NABIR Researchers Report Uptake of Plutonium by Common Soil Microorganisms

Researchers in BER's Natural and Accelerated Bioremediation Research (NABIR) Program reported in the June 8 edition of the journal Environmental Science & Technology that commonly occurring microorganisms can take up the radionuclide plutonium (Pu). Dr. Mary Neu and her co-workers at LANL studied Microbacterium flavescens, a relatively common soil microbe that takes up iron as a nutrient by producing siderophores. Siderophores are agents that bind and transport iron into the cell. The researchers found that the microbe can use the same type of siderophores that transport iron as a mechanism to take up and accumulate Pu. While other researchers have previously reported sorption of some forms of Pu to the surfaces of cells, Neu's work is the first to show unequivocal transport into the cell and to elucidate the mechanism for that transport. Because iron is an essential nutrient for life, iron siderophores are common in bacteria, fungi and even plants, suggesting a major pathway for removal of plutonium from the aqueous phase. The effects of microbes and microbially produced siderophores on plutonium are significant not only for the prediction of the long term fate of such toxics in the environment, but also for the development of novel technologies for bioremediation of plutonium and other actinide elements through removal from the aqueous phase and immobilization in microbial biomass.

Contact: Anna Palmisano, SC-74, 3-9963
Topic Areas:

Division: SC-23.1 Climate and Environmental Sciences Division, BER
      (formerly SC-74 Environmental Sciences Division, OBER)


June 06, 2001

Natural and Accelerated Bioremediation Research (NABIR) Findings Published in Science.

In the May 18, 2001, issue of the journal Science, NABIR researcher Dr. Terry Beveridge of the University of Guelph, Canada, and collaborators at the Virginia Polytechnic Institute and State University published a paper entitled "Bacterial recognition of mineral surfaces: Nanoscale interactions between Shewanella and alpha-FeOOH." Shewanella oneidensis is a bacterium that can "respire" iron (oxy)hydroxide minerals, as well as metals such as chromium and uranium, in the absence of oxygen. Little is known about how bacteria might use a solid mineral substrate for respiration because of the difficulty in observing molecular level processes at the microbe-mineral interface. The researchers used a novel approach to examine the binding of metal reductases in the outer membrane of the bacterium to the mineral surface. Atomic force microscopy measured the binding strength between the bacterium and the mineral surface in the presence and absence of oxygen. Nanomechanical measurements showed an affinity between Shewanella and the iron containing mineral, goethite. This affinity was not measurable in the presence of oxygen or with minerals that were not respired. Molecular modeling suggested that an iron reductase protein in the outer membrane of the bacterium reduced the iron present in goethite as part of the respiratory process. This study is the first to measure microbe-mineral interactions at a nanoscale, and opens the possibility of combining nanoscale measurements with molecular genetics and mineralogy to identify all components of electron transfer in metal and radionuclide reduction during bacterial respiration.

Contact: Anna Palmisano, SC-74, 3-9963
Topic Areas:

Division: SC-23.1 Climate and Environmental Sciences Division, BER
      (formerly SC-74 Environmental Sciences Division, OBER)


June 06, 2001

Natural and Accelerated Bioremediation Research (NABIR) Highlighted at the American Society of Microbiology.

NABIR investigators had a major impact on the annual meeting of the American Society of Microbiology which was attended by over 15,000 scientists. NABIR research was presented in 12 invited talks and over 50 additional scientific papers. NABIR researchers reported their findings in two sessions on "Bioreduction of Metals and Bioremediation of Metal-Contaminated Soils," as well as at sessions on "Subsurface Microbiology," "Anaerobic Respiration," "Molecular Microbiology Ecology," and "Gene Expression in the Environment." Dr. Gil Geesey, a NABIR investigator from Montana State University, won the most prestigious award in environmental microbiology, the 2001 Procter & Gamble Applied and Environmental Microbiology Award. Dr. Geesey was recognized for his research on bacterial-surface interactions, and he presented a lecture entitled "Surfaces: Catalysts of diverse bacterial cell behavior." Other highlights include a report by Dr. James Fredrickson of Pacific Northwest National Laboratory that the highly radiation-resistant bacterium Deinoccoccus radiodurans is endemic to subsurface soils beneath radioactive waste storage tanks at the Hanford reservation, making this microbe especially promising for in situ bioremediation approaches. Dr. Derek Lovley from the University of Massachusetts reported that during active metal reduction, subsurface microbial communities are dominated by metal- and radionuclide-reducing bacteria called Geobacter. Genomes of both Geobacter and Deinococcus have been sequenced by the BER Microbial Genome Program, and researchers are using this information to better understand the potential of these bacteria for bioremediation of metals and radionuclides at DOE sites.

Contact: Anna Palmisano, SC-74, 3-9963
Topic Areas:

Division: SC-23.1 Climate and Environmental Sciences Division, BER
      (formerly SC-74 Environmental Sciences Division, OBER)


March 21, 2001

Fourth Annual DOE Natural and Accelerated Bioremediation Research (NABIR) Program Grantee/Contractor Meeting.

The fourth annual NABIR grantee/contractor meeting was held in Warrenton, VA, on March 11-14, 2001. The nearly 140 attendees included bioremediation researchers, BER program managers, and EM managers and staff. In a keynote address, Dr. Gerald Boyd, Deputy Assistant Secretary of Science and Technology for Environmental Management, emphasized the importance of NABIR research to finding solutions to legacy wastes of radionuclides and metals at DOE sites. EM representatives from headquarters and field operations participated in a roundtable organized by Paul Bayer (SC-74) on connecting NABIR research to EM customer needs. A scientific highlight of the NABIR meeting was a session on the use of data from BER's Microbial Genome Program by NABIR researchers. Genomic data have provided new insights into the physiology and ecology of radionuclide-reducing microorganisms, such as Geobacter and Desulfovibrio, and radiation-resistant microbes, such as Deinococcus. Special sessions were also devoted to new field research projects at the NABIR field research site at ORNL, NABIR research at Uranium Mill Tailing Remedial Action sites, and on Bioremediation and its Societal Implications and Concerns. A "town hall" style session was held as part of ongoing strategic planning for the NABIR program. NABIR researchers agreed that the program's focus on immobilization of metals and radionuclides in the subsurface is appropriate, and that communication of NABIR results to regulators and stakeholders was critical to the acceptance of this approach.

Contact: Anna Palmisano, SC-74, 3-9963 and John Houghton, SC-74, 3-8288
Topic Areas:

Division: SC-23.1 Climate and Environmental Sciences Division, BER
      (formerly SC-74 Environmental Sciences Division, OBER)


February 28, 2001

Field-portable Immunoassay Developed to Measure Uranium.

Uranium is a common legacy waste contaminant at DOE sites. Because it can occur in several chemical forms, it is difficult to quantify the total at a site and differentiate between the uranium compounds. As part of the Natural and Accelerated Bioremediation Research (NABIR) program, Dr. Diane Blake of Tulane University has developed a sensor that can be used to identify the type of uranium compounds and quantify the uranium in the field. The sensor involves the use of monoclonal antibodies. These antibodies were joined with a fluorescent dye to allow quantification. The method was found to have a 10-1000 fold greater sensitivity when compared to more traditional approaches. Monoclonal antibodies have also been developed that recognize cadmium, cobalt, or lead. Dr. Blake's NABIR research has been accepted for publication in the journals Analytical Chimica Acta, ImmunoAssays, and Biosensors and Bioelectronics. A prototype instrument has been developed in collaboration with Sapidyne Instruments, Inc. that is approximately the size of a "Palm Pilot" and allows an easy interface to a PC.

Contact: Anna Palmisano, SC-74, 3-9963
Topic Areas:

Division: SC-23.1 Climate and Environmental Sciences Division, BER
      (formerly SC-74 Environmental Sciences Division, OBER)


February 28, 2001

Research at the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL) on Transition Metal Oxides Contributes to Greater Understanding of Mineral Surface Interactions with Contaminants.

For the first time, EMSL scientist Scott Chambers and postdoctoral associate Tim Droubay have determined the difference in electron energy levels (crystal field splitting) at the surface of three well-defined single crystals of different iron oxides: I-Fe2O3(0001), y-Fe2O3(001), and Fe3O4(001). Until this work, the actual energy difference at the surface of any transition metal oxide was not known. Knowing the differences between surface and bulk crystal field strength is important for obtaining a fundamental understanding of the reactivity of oxide and mineral surfaces. In turn, this fundamental understanding of specific mineral surface-site reactivities substantially improves reactive transport models of contaminants in geologic systems, and allows more effective remediation schemes to be devised. The EMSL molecular beam epitaxy (MBE) system was used to prepare the crystals, and high-energy-resolution x-ray photoemission, synchrotron radiation x-ray absorption spectroscopy, and first-principles atomic multiplet theory were used to analyze the samples. This work was funded by EMSP and will be submitted for publication in Physical Review B.

Contact: Paul Bayer, SC-74, 3-5324
Topic Areas:

Division: SC-23.1 Climate and Environmental Sciences Division, BER
      (formerly SC-74 Environmental Sciences Division, OBER)