Environmental Actinide Mobility: Plutonium and Uranium Interactions with Exopolysaccharides and Siderophores of Aerobic Soil Microbes

Neu, Mary P. ; Vanderberg, Laura

Los Alamos National Laboratory

关键词: Uranium;    Translocation;    Actinides;    59 Basic Biological Sciences;    38 Radiation Chemistry, Radiochemistry, And Nuclear Chemistry;   

DOI  :  10.2172/893875
RP-ID  :  NABIR-1016387-2001
RP-ID  :  None
RP-ID  :  893875

美国|英语

来源: UNT Digital Library

【 摘 要 】

Research efforts into understanding the effect of siderophores and capsules on actinide speciation and resultant environmental behavior are ongoing. Investigations on both siderophores have progressed. The redox chemistry of Pu(VI) and Pu(V) with DFO under acidic conditions was examined by UV-Vis and NMR spectroscopies. Pu(VI) was instantly reduced to Pu(V) by DFO and DFO cleavage resulted. Neither DFO nor the cleavage product appeared to coordinate with Pu(V) in the pH range examined. Growth of S. pilosus for cellular translocation experiments was optimized and experiments to determine DFO-mediated uranium uptake by S. pilosus are underway. OFS siderophore(s) production has been optimized and product identification is underway. Siderophore-like molecules were positive for the Arnow assay and had UV absorbance bands at 250nm and 315nm, suggesting catecholates-type molecules. Siderophores were produced with C13 - C16 as carbon source in AM-1 salts medium with 1.0mM iron. Siderophore accumulation was slowest on C13 due to the slower growth of OFS on this substrate. The C16 concentration in the culture influenced siderophore production, with highest levels at 1.0% and 2.0%.