Bacteria from uranium mining waste pile: interactions with U(VI)

Laser Spectroscopic Studies of Interactions of UVI with Bacterial Phosphate Species

“…Only differences in the quantity of uranyl uptake of this species were found. [11,12] The significant change in uranyl fluorescence after decomposition of B. sphaericus may be explained Table 3. by the decomposition of organophosphates to H 2 PO 4 À , which is released when the cells fragment form a UO 2 (H 2 PO 4 ) 2 precipitate with U VI .…”

“…[9] Bacteria can actively change their chemical environment; in particular, they can achieve a chemical microenvironment close to the cell wall that can affect the oxidation state or the solubility of actinides. [1,8,10,11] The general chemical environment can also affect bacteria. Lack of nutrients, competition by other organisms, or changes in overall physical and chemical conditions of the aquatic system can lead to sporulation or the death of cells.…”

Complexation of U(VI) with Cells of Thiobacillus ferrooxidans and Thiomonas cuprina of Different Geological Origin

“…No significant increase of U(VI) accumulation was observed for all strains with increasing pH from 1.5 to 4.0. Details on the effect of increasing pH on the accumulation capacity for the strains Thiobacillus ferrooxidans ATCC 23270 T and 33020 are described in [21],…”

“…Our studies included a quantification of the accumulated U(VI) and various extraction studies to determine the amount of uranium which is weakly bound to the bacterial surface [21], The remaining U(VI) that could not be removed from the biomass by extraction was characterized by time-resolved laser fluorescence spectroscopy (TRLFS). This method has proved to be a versatile tool for speciation of U(VI) in the micro-molar concentration range, and has been used to determine stability constants for several inorganic and organic ligands [22][23][24], TRLFS is not only useful to quantify different metal complexes with well-defined ligands but also yields valuable information about structure and binding strength of metal ions with large polyfunctional ligands such as humic substances [25,26] and microorganisms.…”

Uranium(VI) complexes with phospholipid model compounds – A laser spectroscopic study

“…Certain bacteria strains can bio-accumulate relatively large amounts of uranium, which can be transported and released elsewhere in the environment [2][3][4][5][6][7][8][9][10][11]. A number of bacteria are specialized to live under harsh environmental conditions, like acidic pH values, which are typical of uranium mining waste piles or deposits [3].…”