Respiratory U6+ reduction and U4+ nanoparticle formation in Geobacter lovleyi and Anaeromyxobacter dehalogenans
EMSL Project ID
34929
Abstract
situ bioremediation strategy at U-contaminated DOE sites. U4+ nanoparticles generated by resting cells (i.e., representing artificial non-growth conditions) of metal-reducing bacteria have been characterized; however, the localization, size and characteristics of U4+ nanoparticles formed when U6+ serves as a respiratory electron acceptor (i.e., as a substrate for growth) are unclear. This is a major knowledge gap because respiratory U6+ reduction is likely the predominant microbial process leading to U4+ nanoparticle formation in situ. Since the properties of the reduced U4+ materials influence its stability, transport and fate, U4+ nanoparticles generated in respiratory processes must be investigated. To explore U4+ generated in respiratory processes, Geobacter sp. and an Anaeromyxobater sp. will be grown in batch and chemostat vessels with U6+ as electron acceptor. The size (overall and crsytallite) and localization of the U4+ nanoparticles will be analyzed with wholemount TEM and Cryo-TEM and compared with data generated in resting cell experiments. Since the characteristics of the reduced material strongly influences U stability, knowledge of the properties of the U4+ nanoparticles generated in respiratory processes is needed for predicting the behavior and long-term fate of U in the contaminated subsurface.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2009-10-05
End Date
2011-09-30
Status
Closed
Released Data Link
Team
Principal Investigator