Structure and function of subsurface microbial communities affecting radionuclide transport and bioimmobilization

Technical Report · Tue May 01 04:00:00 EDT 2012

DOI:https://doi.org/10.2172/1149158· OSTI ID:1149158

Kostka, Joel E. ^[1]; Prakash, Om ^[2]; Green, Stefan J. ^[2]; Akob, Denise ^[2]; Jasrotia, Puja ^[2]; Kerkhof, Lee ^[3]; Chin, Kuk-Jeong ^[4]; Sheth, Mili ^[4]; Keller, Martin ^[5]; Venkateswaran, Amudhan ^[5]; Elkins, James G. ^[6]; Stucki, Joseph W. ^[6]

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1. Florida State Univ., Tallahassee, FL (United States); Georgia State University
2. Florida State Univ., Tallahassee, FL (United States)
3. Rutgers Univ., New Brunswick, NJ (United States)
4. Georgia State Univ., Atlanta, GA (United States)
5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
6. Univ. of Illinois, Urbana-Champaign, IL (United States)

Our objectives were to: 1) isolate and characterize novel anaerobic prokaryotes from subsurface environments exposed to high levels of mixed contaminants (U(VI), nitrate, sulfate), 2) elucidate the diversity and distribution of metabolically active metal- and nitrate-reducing prokaryotes in subsurface sediments, and 3) determine the biotic and abiotic mechanisms linking electron transport processes (nitrate, Fe(III), and sulfate reduction) to radionuclide reduction and immobilization. Mechanisms of electron transport and U(VI) transformation were examined under near in situ conditions in sediment microcosms and in field investigations. Field sampling was conducted at the Oak Ridge Field Research Center (ORFRC), in Oak Ridge, Tennessee. The ORFRC subsurface is exposed to mixed contamination predominated by uranium and nitrate. In short, we effectively addressed all 3 stated objectives of the project. In particular, we isolated and characterized a large number of novel anaerobes with a high bioremediation potential that can be used as model organisms, and we are now able to quantify the function of subsurface sedimentary microbial communities in situ using state-of-the-art gene expression methods (molecular proxies).

• Research Organization: Georgia State Univ., Atlanta, GA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: FG02-07ER64376
• OSTI ID: 1149158
• Report Number(s): ERSP--FinalReport
• Country of Publication: United States
• Language: English