Accumulation and cellular distribution of uranium in Thiobacillus ferrooxidans

Removal of uranium by an exopolysaccharide from Pseudomonas sp.

“…Uranium uptake declined below pH 5. This pH effect has been reported previously by several investigators when whole cells were used (DiSpirito et al 1983;Friss and MyersKeith 1985). The uptake of uranium by exopolymer was studied between 4°C and 50°C and the amounts of uranium were constant within this range.…”

“…The use of microbial cells as biosorbents of uranium (U) has received attention from varius workers (Horikoshi et al 1981;Strandberg et al 1981;DiSpirito et al 1983), but in these cases metal accumulation was performed by using whole cells. The specific objective of the work reported here was to evaluate the utility of a extracellular polysaccharide produced by Pseudomonas sp.…”

Uranium accumulation by Pseudomonas sp. EPS-5028

“…Toxic metals rarely breach an energized plasma membrane unless they pass through specialized transporters to be detoxified within the cell or rapidly pumped out again (Mullen et al 1989). However, there is no direct evidence for the presence of a uranium transporter in Thiobacillusferrooxidans or in any other microorganism studied (DiSpirito et al 1983). We do not know how uranium enters the cell so rapidly (metabolism has been discounted).…”

Growth in sulfidic mineral environments: metal resistance mechanisms in acidophilic micro-organisms

“…In many cases, toxicity studies have been carried out with these metals on acidophiles. Examples are U(VI) toxicity via inhibition of Fe(II) oxidation and CO 2 fixation (Dispiroto et al, 1983) and At. ferrooxidans growth inhibition by >15 mM Cr(III) (Wong et al, 1982).…”