{"73142":{"#nid":"73142","#data":{"type":"news","title":"Bacteria Aid in Clean-Up of Uranium Contamination","body":[{"value":"\u003Cp\u003EIn research that could help control contamination from the radioactive element uranium, scientists have discovered that some bacteria found in the soil and subsurface can release phosphate that converts uranium contamination into an insoluble and immobile form. \u003C\/p\u003E\n\u003Cp\u003EBased on laboratory studies, Georgia Institute of Technology researchers report promising results using bacterial species from three genera isolated from subsurface soils collected at a U.S. Department of Energy (DOE) Field Research Center site in Oak Ridge, Tenn. Researchers conducted preliminary screenings of many bacterial isolates and found several candidate strains that released inorganic phosphate after hydrolyzing an organo-phosphate source the researchers provided.\n\u003C\/p\u003E\n\u003Cp\u003EThe bioremediation research project, funded for three years by DOE\u0027s Environmental Remediation Sciences Division, is in its early stages. Research team member Melanie Beazley, a Ph.D. student in the Georgia Tech School of Earth and Atmospheric Sciences, presented preliminary findings on March 30 at the 231st American Chemical Society National Meeting in Atlanta. \n\u003C\/p\u003E\n\u003Cp\u003E\u0022These organisms release phosphate into the medium, but the precipitation (of uranium phosphate) occurs chemically,\u0022 explained Assistant Professor of Earth and Atmospheric Sciences Martial Taillefert, co-director of the study. \u0022That is the biomineralization of uranium and the novelty of this approach.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EThe process begins when the bacteria - from the genera \u003Cem\u003ERhanella\u003C\/em\u003E, \u003Cem\u003EBacillus\u003C\/em\u003E and possibly \u003Cem\u003EArthrobacter\u003C\/em\u003E -- degrade an organo-phosphate compound such as glycerol-3-phosphate (G3P) or phytic acid (IP6), which can be present in subsurface soils. \n\u003C\/p\u003E\n\u003Cp\u003E\u0022During their growth, the organisms liberate phosphate they derive from the organo-phosphate compound,\u0022 said project co-director Patricia Sobecky, an associate professor of biology. \u0022The free phosphate is released to the surrounding media, which is a solution in the lab. Then we conduct assays to see how much uranium is mineralized by the phosphate released by the bacteria.\u0022 \u003C\/p\u003E\n\u003Cp\u003EThe bacteria\u0027s role is crucial in this process because uranium cannot dissociate the organo-phosphate compound chemically, Taillefert explained. So uranium in the presence of organo-phosphate alone does not result in significant uranium precipitation.\n\u003C\/p\u003E\n\u003Cp\u003ESobecky and her Ph.D. student Robert Martinez are conducting the microbiological and physiological component of the research, while Taillefert and Beazley study the uranium chemistry and analyze distribution of different forms of uranium during incubation in the lab.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022The devil\u0027s in the details with the chemistry of uranium:  There are numerous forms of uranium in the environment, which are all influenced by the natural properties of soils and groundwater,\u0022 Taillefert said. \n\u003C\/p\u003E\n\u003Cp\u003ESobecky added, \u0022What we\u0027re doing now is optimizing the assay conditions and the techniques to analyze the distribution of uranium species in the lab.\u0022 \n\u003C\/p\u003E\n\u003Cp\u003ETraditionally, DOE has funded research investigating the chemical reduction of uranium contamination. But there are two approaches to immobilizing uranium. One strategy reduces uranium (VI) to uranium (IV), which is, in principle, immobile. But the uranium can re-oxidize even with traces of oxygen from rainwater seeping into the groundwater. The Georgia Tech approach biomineralizes uranium (VI) into an insoluble form of uranium via phosphate precipitation.\n\u003C\/p\u003E\n\u003Cp\u003EAs they work toward a bioremediation strategy that will work in the field, researchers must design a mechanism to deal with competing organisms in the soil that might sequester the free phosphate, Sobecky noted. Though their current grant does not cover the cost of a field study, researchers hope to obtain funds in the future to test their strategy at Oak Ridge and potentially other DOE sites. Uranium contamination is a concern at DOE sites because it can migrate to groundwater in surrounding areas, Taillefert noted.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022At this point, we know the organisms we\u0027re studying are active in precipitating uranium phosphate,\u0022 he said. \u0022Now we need to determine how chemically stable it is.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EResearchers also have learned that when the bacteria are releasing phosphate from G3P, the bacteria can tolerate the toxic uranium and can continue to grow once the uranium is precipitated by the released phosphate. \n\u003C\/p\u003E\n\u003Cp\u003E\u0022Our challenge now is fine-tuning the conditions around the bacterium so eventually it can thrive and work chemically in a natural setting,\u0022 Taillefert said. \n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EResearch News \u0026amp; Publications Office\u003Cbr \/\u003E\nGeorgia Institute of Technology\u003Cbr \/\u003E\n75 Fifth Street, N.W., Suite 100\u003Cbr \/\u003E\nAtlanta, Georgia 30308 USA \u003C\/strong\u003E\n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EMedia Relations Contacts\u003C\/strong\u003E: Jane Sanders (404-894-2214); E-mail: (\u003Ca href=\u0022mailto:jane.sanders@edi.gatech.edu\u0022\u003Ejane.sanders@edi.gatech.edu\u003C\/a\u003E) or John Toon (404-894-6986); E-mail: (\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E)\n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003ETechnical Contacts\u003C\/strong\u003E: Patricia Sobecky (404-894-5819); E-mail: (\u003Ca href=\u0022mailto:patricia.sobecky@biology.gatech.edu\u0022\u003Epatricia.sobecky@biology.gatech.edu\u003C\/a\u003E) or Martial Taillefert (404-894-6043); E-mail: (\u003Ca href=\u0022mailto:martial.taillefert@eas.gatech.edu\u0022\u003Emartial.taillefert@eas.gatech.edu\u003C\/a\u003E)\n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWriter\u003C\/strong\u003E: Jane Sanders\n\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Research shows organisms found in soil can immobilize radioactive material"}],"field_summary":[{"value":"In research that could help control contamination from the radioactive element uranium, scientists have discovered that bacteria found in the soil and subsurface can help convert uranium contamination into an insoluble and immobile form.","format":"limited_html"}],"field_summary_sentence":[{"value":"Bacteria may help clean up uranium contamination"}],"uid":"27303","created_gmt":"2006-03-30 01:00:00","changed_gmt":"2016-10-08 03:03:34","author":"John Toon","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2006-03-30T00:00:00-05:00","iso_date":"2006-03-30T00:00:00-05:00","tz":"America\/New_York"},"extras":[],"hg_media":{"73143":{"id":"73143","type":"image","title":"Martial Taillefert and Patricia Sobecky","body":null,"created":"1449177979","gmt_created":"2015-12-03 21:26:19","changed":"1475894671","gmt_changed":"2016-10-08 02:44:31"},"73144":{"id":"73144","type":"image","title":"Melanie Beazley and Robert Martinez","body":null,"created":"1449177979","gmt_created":"2015-12-03 21:26:19","changed":"1475894671","gmt_changed":"2016-10-08 02:44:31"}},"media_ids":["73143","73144"],"related_links":[{"url":"http:\/\/www.biology.gatech.edu\/faculty\/patricia-sobecky\/","title":"Patricia Sobecky"},{"url":"http:\/\/www.eas.gatech.edu\/people\/faculty\/taillefert.htm","title":"Martial Taillefert"},{"url":"http:\/\/www.biology.gatech.edu\/","title":"School of Biology"},{"url":"http:\/\/www.eas.gatech.edu\/","title":"School of Earth and Atmospheric Sciences"}],"groups":[{"id":"1188","name":"Research Horizons"}],"categories":[],"keywords":[],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cstrong\u003EJohn Toon\u003C\/strong\u003E\u003Cbr \/\u003EResearch News \u0026amp; Publications Office\u003Cbr \/\u003E\u003Ca href=\u0022http:\/\/www.gatech.edu\/contact\/index.html?id=jt7\u0022\u003EContact John Toon\u003C\/a\u003E\u003Cbr \/\u003E\u003Cstrong\u003E404-894-6986\u003C\/strong\u003E","format":"limited_html"}],"email":["jtoon@gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}