title: Spatial distribution of an uranium-respiring betaproteobacterium at the Rifle, CO field research site.
abstract: The Department of Energy's Integrated Field-Scale Subsurface Research Challenge Site (IFRC) at Rifle, Colorado was created to address the gaps in knowledge on the mechanisms and rates of U(VI) bioreduction in alluvial sediments. Previous studies at the Rifle IFRC have linked microbial processes to uranium immobilization during acetate amendment. Several key bacteria believed to be involved in radionuclide containment have been described; however, most of the evidence implicating uranium reduction with specific microbiota has been indirect. Here, we report on the cultivation of a microorganism from the Rifle IFRC that reduces uranium and appears to utilize it as a terminal electron acceptor for respiration with acetate as electron donor. Furthermore, this bacterium constitutes a significant proportion of the subsurface sediment community prior to biostimulation based on TRFLP profiling of 16S rRNA genes. 16S rRNA gene sequence analysis indicates that the microorganism is a betaproteobacterium with a high similarity to Burkholderia fungorum. This is, to our knowledge, the first report of a betaproteobacterium capable of uranium respiration. Our results indicate that this microorganism occurs commonly in alluvial sediments located between 3-6 m below ground surface at Rifle and may play a role in the initial reduction of uranium at the site.
authors: Inst. of Marine and Coastal Science, Rutgers University, New Brunswick, New Jersey, United States of America.
authors: Nicole M
authors: NM
authors: Koribanics
authors: Inst. of Marine and Coastal Science, Rutgers University, New Brunswick, New Jersey, United States of America.
authors: Steven J
authors: SJ
authors: Tuorto
authors: Inst. of Marine and Coastal Science, Rutgers University, New Brunswick, New Jersey, United States of America; Dept. of Biochemistry and Microbiology, Rutgers University, New Brunswick, New Jersey, United States of America.
authors: Nora
authors: N
authors: Lopez-Chiaffarelli
authors: Inst. of Marine and Coastal Science, Rutgers University, New Brunswick, New Jersey, United States of America.
authors: Lora R
authors: LR
authors: McGuinness
authors: Dept. of Biochemistry and Microbiology, Rutgers University, New Brunswick, New Jersey, United States of America.
authors: Max M
authors: MM
authors: Häggblom
authors: Lawrence Berkeley National Laboratory, Berkeley, California, United States of America.
authors: Kenneth H
authors: KH
authors: Williams
authors: Lawrence Berkeley National Laboratory, Berkeley, California, United States of America.
authors: Philip E
authors: PE
authors: Long
authors: Inst. of Marine and Coastal Science, Rutgers University, New Brunswick, New Jersey, United States of America.
authors: Lee J
authors: LJ
authors: Kerkhof
mesh_terms: D000085:Acetates / Q000737:chemistry; D020562:Betaproteobacteria / Q000235:genetics / Q000302:isolation & purification*; D001673:Biodegradation, Environmental; D019117:Burkholderia / Q000235:genetics; D003120:Colorado; D004583:Electrons; D019015:Geologic Sediments / Q000382:microbiology; D060587:Groundwater; D016013:Likelihood Functions; D013058:Mass Spectrometry; D064307:Microbiota; D008969:Molecular Sequence Data; D009942:Organometallic Compounds / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000737:chemistry; D011868:Radioisotopes / Q000737:chemistry; D012988:Soil Microbiology; D014501:Uranium / Q000737:chemistry*
chemical_list: D000085:Acetates; D009942:Organometallic Compounds; D012336:RNA, Ribosomal, 16S; D011868:Radioisotopes; C005460:uranyl acetate; D014501:Uranium; D010100:Oxygen